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Diffstat (limited to 'gcc/ada/gcc-interface/trans.c')
| -rw-r--r-- | gcc/ada/gcc-interface/trans.c | 11009 |
1 files changed, 0 insertions, 11009 deletions
diff --git a/gcc/ada/gcc-interface/trans.c b/gcc/ada/gcc-interface/trans.c deleted file mode 100644 index 39059cb..0000000 --- a/gcc/ada/gcc-interface/trans.c +++ /dev/null @@ -1,11009 +0,0 @@ -/**************************************************************************** - * * - * GNAT COMPILER COMPONENTS * - * * - * T R A N S * - * * - * C Implementation File * - * * - * Copyright (C) 1992-2021, Free Software Foundation, Inc. * - * * - * GNAT is free software; you can redistribute it and/or modify it under * - * terms of the GNU General Public License as published by the Free Soft- * - * ware Foundation; either version 3, or (at your option) any later ver- * - * sion. GNAT is distributed in the hope that it will be useful, but WITH- * - * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * - * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * - * for more details. You should have received a copy of the GNU General * - * Public License distributed with GNAT; see file COPYING3. If not see * - * <http://www.gnu.org/licenses/>. * - * * - * GNAT was originally developed by the GNAT team at New York University. * - * Extensive contributions were provided by Ada Core Technologies Inc. * - * * - ****************************************************************************/ - -#include "config.h" -#include "system.h" -#include "coretypes.h" -#include "target.h" -#include "function.h" -#include "bitmap.h" -#include "tree.h" -#include "gimple-expr.h" -#include "stringpool.h" -#include "cgraph.h" -#include "predict.h" -#include "diagnostic.h" -#include "alias.h" -#include "fold-const.h" -#include "stor-layout.h" -#include "stmt.h" -#include "varasm.h" -#include "output.h" -#include "debug.h" -#include "libfuncs.h" /* For set_stack_check_libfunc. */ -#include "tree-iterator.h" -#include "gimplify.h" -#include "opts.h" -#include "common/common-target.h" -#include "gomp-constants.h" -#include "stringpool.h" -#include "attribs.h" -#include "tree-nested.h" - -#include "ada.h" -#include "adadecode.h" -#include "types.h" -#include "atree.h" -#include "namet.h" -#include "nlists.h" -#include "snames.h" -#include "stringt.h" -#include "uintp.h" -#include "urealp.h" -#include "fe.h" -#include "sinfo.h" -#include "einfo.h" -#include "gadaint.h" -#include "ada-tree.h" -#include "gigi.h" - -/* We should avoid allocating more than ALLOCA_THRESHOLD bytes via alloca, - for fear of running out of stack space. If we need more, we use xmalloc - instead. */ -#define ALLOCA_THRESHOLD 1000 - -/* Pointers to front-end tables accessed through macros. */ -Node_Header *Node_Offsets_Ptr; -any_slot *Slots_Ptr; -Node_Id *Next_Node_Ptr; -Node_Id *Prev_Node_Ptr; -struct Elist_Header *Elists_Ptr; -struct Elmt_Item *Elmts_Ptr; -struct String_Entry *Strings_Ptr; -Char_Code *String_Chars_Ptr; -struct List_Header *List_Headers_Ptr; - -/* Highest number in the front-end node table. */ -int max_gnat_nodes; - -/* True when gigi is being called on an analyzed but unexpanded - tree, and the only purpose of the call is to properly annotate - types with representation information. */ -bool type_annotate_only; - -/* List of N_Validate_Unchecked_Conversion nodes in the unit. */ -static vec<Node_Id> gnat_validate_uc_list; - -/* List of expressions of pragma Compile_Time_{Error|Warning} in the unit. */ -static vec<Node_Id> gnat_compile_time_expr_list; - -/* When not optimizing, we cache the 'First, 'Last and 'Length attributes - of unconstrained array IN parameters to avoid emitting a great deal of - redundant instructions to recompute them each time. */ -struct GTY (()) parm_attr_d { - int id; /* GTY doesn't like Entity_Id. */ - int dim; - tree first; - tree last; - tree length; -}; - -typedef struct parm_attr_d *parm_attr; - -/* Structure used to record information for a function. */ -struct GTY(()) language_function { - vec<parm_attr, va_gc> *parm_attr_cache; - bitmap named_ret_val; - vec<tree, va_gc> *other_ret_val; - int gnat_ret; -}; - -#define f_parm_attr_cache \ - DECL_STRUCT_FUNCTION (current_function_decl)->language->parm_attr_cache - -#define f_named_ret_val \ - DECL_STRUCT_FUNCTION (current_function_decl)->language->named_ret_val - -#define f_other_ret_val \ - DECL_STRUCT_FUNCTION (current_function_decl)->language->other_ret_val - -#define f_gnat_ret \ - DECL_STRUCT_FUNCTION (current_function_decl)->language->gnat_ret - -/* A structure used to gather together information about a statement group. - We use this to gather related statements, for example the "then" part - of a IF. In the case where it represents a lexical scope, we may also - have a BLOCK node corresponding to it and/or cleanups. */ - -struct GTY((chain_next ("%h.previous"))) stmt_group { - struct stmt_group *previous; /* Previous code group. */ - tree stmt_list; /* List of statements for this code group. */ - tree block; /* BLOCK for this code group, if any. */ - tree cleanups; /* Cleanups for this code group, if any. */ -}; - -static GTY(()) struct stmt_group *current_stmt_group; - -/* List of unused struct stmt_group nodes. */ -static GTY((deletable)) struct stmt_group *stmt_group_free_list; - -/* A structure used to record information on elaboration procedures - we've made and need to process. - - ??? gnat_node should be Node_Id, but gengtype gets confused. */ - -struct GTY((chain_next ("%h.next"))) elab_info { - struct elab_info *next; /* Pointer to next in chain. */ - tree elab_proc; /* Elaboration procedure. */ - int gnat_node; /* The N_Compilation_Unit. */ -}; - -static GTY(()) struct elab_info *elab_info_list; - -/* Stack of exception pointer variables. Each entry is the VAR_DECL - that stores the address of the raised exception. Nonzero means we - are in an exception handler. Not used in the zero-cost case. */ -static GTY(()) vec<tree, va_gc> *gnu_except_ptr_stack; - -/* In ZCX case, current exception pointer. Used to re-raise it. */ -static GTY(()) tree gnu_incoming_exc_ptr; - -/* Stack for storing the current elaboration procedure decl. */ -static GTY(()) vec<tree, va_gc> *gnu_elab_proc_stack; - -/* Stack of labels to be used as a goto target instead of a return in - some functions. See processing for N_Subprogram_Body. */ -static GTY(()) vec<tree, va_gc> *gnu_return_label_stack; - -/* Stack of variable for the return value of a function with copy-in/copy-out - parameters. See processing for N_Subprogram_Body. */ -static GTY(()) vec<tree, va_gc> *gnu_return_var_stack; - -/* Structure used to record information for a range check. */ -struct GTY(()) range_check_info_d { - tree low_bound; - tree high_bound; - tree disp; - bool neg_p; - tree type; - tree invariant_cond; - tree inserted_cond; -}; - -typedef struct range_check_info_d *range_check_info; - -/* Structure used to record information for a loop. */ -struct GTY(()) loop_info_d { - tree fndecl; - tree stmt; - tree loop_var; - tree low_bound; - tree high_bound; - tree omp_loop_clauses; - tree omp_construct_clauses; - enum tree_code omp_code; - vec<range_check_info, va_gc> *checks; - vec<tree, va_gc> *invariants; -}; - -typedef struct loop_info_d *loop_info; - -/* Stack of loop_info structures associated with LOOP_STMT nodes. */ -static GTY(()) vec<loop_info, va_gc> *gnu_loop_stack; - -/* The stacks for N_{Push,Pop}_*_Label. */ -static vec<Entity_Id> gnu_constraint_error_label_stack; -static vec<Entity_Id> gnu_storage_error_label_stack; -static vec<Entity_Id> gnu_program_error_label_stack; - -/* Map GNAT tree codes to GCC tree codes for simple expressions. */ -static enum tree_code gnu_codes[Number_Node_Kinds]; - -static void init_code_table (void); -static tree get_elaboration_procedure (void); -static void Compilation_Unit_to_gnu (Node_Id); -static bool empty_stmt_list_p (tree); -static void record_code_position (Node_Id); -static void insert_code_for (Node_Id); -static void add_cleanup (tree, Node_Id); -static void add_stmt_list (List_Id); -static tree build_stmt_group (List_Id, bool); -static inline bool stmt_group_may_fallthru (void); -static enum gimplify_status gnat_gimplify_stmt (tree *); -static void elaborate_all_entities (Node_Id); -static void process_freeze_entity (Node_Id); -static void process_decls (List_Id, List_Id, Node_Id, bool, bool); -static tree emit_check (tree, tree, int, Node_Id); -static tree build_unary_op_trapv (enum tree_code, tree, tree, Node_Id); -static tree build_binary_op_trapv (enum tree_code, tree, tree, tree, Node_Id); -static tree convert_with_check (Entity_Id, tree, bool, bool, Node_Id); -static bool addressable_p (tree, tree); -static tree assoc_to_constructor (Entity_Id, Node_Id, tree); -static tree pos_to_constructor (Node_Id, tree); -static void validate_unchecked_conversion (Node_Id); -static void set_expr_location_from_node (tree, Node_Id, bool = false); -static void set_gnu_expr_location_from_node (tree, Node_Id); -static bool set_end_locus_from_node (tree, Node_Id); -static int lvalue_required_p (Node_Id, tree, bool, bool); -static tree build_raise_check (int, enum exception_info_kind); -static tree create_init_temporary (const char *, tree, tree *, Node_Id); -static bool maybe_make_gnu_thunk (Entity_Id gnat_thunk, tree gnu_thunk); - -/* This makes gigi's file_info_ptr visible in this translation unit, - so that Sloc_to_locus can look it up when deciding whether to map - decls to instances. */ - -static struct File_Info_Type *file_map; - -/* Return the string of the identifier allocated for the file name Id. */ - -static const char* -File_Name_to_gnu (Name_Id Id) -{ - /* __gnat_to_canonical_file_spec translates file names from pragmas - Source_Reference that contain host style syntax not understood by GDB. */ - const char *name = __gnat_to_canonical_file_spec (Get_Name_String (Id)); - - /* Use the identifier table to make a permanent copy of the file name as - the name table gets reallocated after Gigi returns but before all the - debugging information is output. */ - return IDENTIFIER_POINTER (get_identifier (name)); -} - -/* This is the main program of the back-end. It sets up all the table - structures and then generates code. */ - -void -gigi (Node_Id gnat_root, - int max_gnat_node, - int number_name ATTRIBUTE_UNUSED, - Node_Header *node_offsets_ptr, - any_slot *slots_ptr, - Node_Id *next_node_ptr, - Node_Id *prev_node_ptr, - struct Elist_Header *elists_ptr, - struct Elmt_Item *elmts_ptr, - struct String_Entry *strings_ptr, - Char_Code *string_chars_ptr, - struct List_Header *list_headers_ptr, - Nat number_file, - struct File_Info_Type *file_info_ptr, - Entity_Id standard_boolean, - Entity_Id standard_integer, - Entity_Id standard_character, - Entity_Id standard_long_long_float, - Entity_Id standard_exception_type, - Int gigi_operating_mode) -{ - Node_Id gnat_iter; - Entity_Id gnat_literal; - tree t, ftype, int64_type; - struct elab_info *info; - int i; - - max_gnat_nodes = max_gnat_node; - - Node_Offsets_Ptr = node_offsets_ptr; - Slots_Ptr = slots_ptr; - Next_Node_Ptr = next_node_ptr; - Prev_Node_Ptr = prev_node_ptr; - Elists_Ptr = elists_ptr; - Elmts_Ptr = elmts_ptr; - Strings_Ptr = strings_ptr; - String_Chars_Ptr = string_chars_ptr; - List_Headers_Ptr = list_headers_ptr; - - type_annotate_only = (gigi_operating_mode == 1); - - if (Generate_SCO_Instance_Table != 0) - { - file_map = file_info_ptr; - maybe_create_decl_to_instance_map (number_file); - } - - for (i = 0; i < number_file; i++) - { - /* We rely on the order isomorphism between files and line maps. */ - if ((int) LINEMAPS_ORDINARY_USED (line_table) != i) - { - gcc_assert (i > 0); - error ("%s contains too many lines", - File_Name_to_gnu (file_info_ptr[i - 1].File_Name)); - } - - /* We create the line map for a source file at once, with a fixed number - of columns chosen to avoid jumping over the next power of 2. */ - linemap_add (line_table, LC_ENTER, 0, - File_Name_to_gnu (file_info_ptr[i].File_Name), 1); - linemap_line_start (line_table, file_info_ptr[i].Num_Source_Lines, 252); - linemap_position_for_column (line_table, 252 - 1); - linemap_add (line_table, LC_LEAVE, 0, NULL, 0); - } - - gcc_assert (Nkind (gnat_root) == N_Compilation_Unit); - - /* Declare the name of the compilation unit as the first global - name in order to make the middle-end fully deterministic. */ - t = create_concat_name (Defining_Entity (Unit (gnat_root)), NULL); - first_global_object_name = ggc_strdup (IDENTIFIER_POINTER (t)); - - /* Initialize ourselves. */ - init_code_table (); - init_gnat_decl (); - init_gnat_utils (); - - /* If we are just annotating types, give VOID_TYPE zero sizes to avoid - errors. */ - if (type_annotate_only) - { - TYPE_SIZE (void_type_node) = bitsize_zero_node; - TYPE_SIZE_UNIT (void_type_node) = size_zero_node; - } - - /* Enable GNAT stack checking method if needed */ - if (!Stack_Check_Probes_On_Target) - set_stack_check_libfunc ("_gnat_stack_check"); - - /* Retrieve alignment settings. */ - double_float_alignment = get_target_double_float_alignment (); - double_scalar_alignment = get_target_double_scalar_alignment (); - - /* Record the builtin types. Define `integer' and `character' first so that - dbx will output them first. */ - record_builtin_type ("integer", integer_type_node, false); - record_builtin_type ("character", char_type_node, false); - record_builtin_type ("boolean", boolean_type_node, false); - record_builtin_type ("void", void_type_node, false); - - /* Save the type we made for integer as the type for Standard.Integer. */ - save_gnu_tree (Base_Type (standard_integer), - TYPE_NAME (integer_type_node), - false); - - /* Likewise for character as the type for Standard.Character. */ - finish_character_type (char_type_node); - save_gnu_tree (Base_Type (standard_character), - TYPE_NAME (char_type_node), - false); - - /* Likewise for boolean as the type for Standard.Boolean. */ - save_gnu_tree (Base_Type (standard_boolean), - TYPE_NAME (boolean_type_node), - false); - gnat_literal = First_Literal (Base_Type (standard_boolean)); - t = UI_To_gnu (Enumeration_Rep (gnat_literal), boolean_type_node); - gcc_assert (t == boolean_false_node); - t = create_var_decl (get_entity_name (gnat_literal), NULL_TREE, - boolean_type_node, t, true, false, false, false, false, - true, false, NULL, gnat_literal); - save_gnu_tree (gnat_literal, t, false); - gnat_literal = Next_Literal (gnat_literal); - t = UI_To_gnu (Enumeration_Rep (gnat_literal), boolean_type_node); - gcc_assert (t == boolean_true_node); - t = create_var_decl (get_entity_name (gnat_literal), NULL_TREE, - boolean_type_node, t, true, false, false, false, false, - true, false, NULL, gnat_literal); - save_gnu_tree (gnat_literal, t, false); - - /* Declare the building blocks of function nodes. */ - void_list_node = build_tree_list (NULL_TREE, void_type_node); - void_ftype = build_function_type_list (void_type_node, NULL_TREE); - ptr_void_ftype = build_pointer_type (void_ftype); - - /* Now declare run-time functions. */ - malloc_decl - = create_subprog_decl (get_identifier ("__gnat_malloc"), NULL_TREE, - build_function_type_list (ptr_type_node, sizetype, - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, - false, NULL, Empty); - DECL_IS_MALLOC (malloc_decl) = 1; - - free_decl - = create_subprog_decl (get_identifier ("__gnat_free"), NULL_TREE, - build_function_type_list (void_type_node, - ptr_type_node, NULL_TREE), - NULL_TREE, is_default, true, true, true, false, - false, NULL, Empty); - - realloc_decl - = create_subprog_decl (get_identifier ("__gnat_realloc"), NULL_TREE, - build_function_type_list (ptr_type_node, - ptr_type_node, sizetype, - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, - false, NULL, Empty); - - /* This is used for 64-bit multiplication with overflow checking. */ - int64_type = gnat_type_for_size (64, 0); - mulv64_decl - = create_subprog_decl (get_identifier ("__gnat_mulv64"), NULL_TREE, - build_function_type_list (int64_type, int64_type, - int64_type, NULL_TREE), - NULL_TREE, is_default, true, true, true, false, - false, NULL, Empty); - - if (Enable_128bit_Types) - { - tree int128_type = gnat_type_for_size (128, 0); - mulv128_decl - = create_subprog_decl (get_identifier ("__gnat_mulv128"), NULL_TREE, - build_function_type_list (int128_type, - int128_type, - int128_type, - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, - false, NULL, Empty); - } - - /* Name of the _Parent field in tagged record types. */ - parent_name_id = get_identifier (Get_Name_String (Name_uParent)); - - /* Name of the Not_Handled_By_Others field in exception record types. */ - not_handled_by_others_name_id = get_identifier ("not_handled_by_others"); - - /* Make the types and functions used for exception processing. */ - except_type_node = gnat_to_gnu_type (Base_Type (standard_exception_type)); - - for (t = TYPE_FIELDS (except_type_node); t; t = DECL_CHAIN (t)) - if (DECL_NAME (t) == not_handled_by_others_name_id) - { - not_handled_by_others_decl = t; - break; - } - gcc_assert (DECL_P (not_handled_by_others_decl)); - - jmpbuf_type - = build_array_type (gnat_type_for_mode (Pmode, 0), - build_index_type (size_int (5))); - record_builtin_type ("JMPBUF_T", jmpbuf_type, true); - jmpbuf_ptr_type = build_pointer_type (jmpbuf_type); - - /* Functions to get and set the jumpbuf pointer for the current thread. */ - get_jmpbuf_decl - = create_subprog_decl - (get_identifier ("system__soft_links__get_jmpbuf_address_soft"), - NULL_TREE, build_function_type_list (jmpbuf_ptr_type, NULL_TREE), - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - - set_jmpbuf_decl - = create_subprog_decl - (get_identifier ("system__soft_links__set_jmpbuf_address_soft"), - NULL_TREE, build_function_type_list (void_type_node, jmpbuf_ptr_type, - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - - get_excptr_decl - = create_subprog_decl - (get_identifier ("system__soft_links__get_gnat_exception"), NULL_TREE, - build_function_type_list (build_pointer_type (except_type_node), - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - - /* setjmp returns an integer and has one operand, which is a pointer to - a jmpbuf. */ - setjmp_decl - = create_subprog_decl - (get_identifier ("__builtin_setjmp"), NULL_TREE, - build_function_type_list (integer_type_node, jmpbuf_ptr_type, - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - set_decl_built_in_function (setjmp_decl, BUILT_IN_NORMAL, BUILT_IN_SETJMP); - - /* update_setjmp_buf updates a setjmp buffer from the current stack pointer - address. */ - update_setjmp_buf_decl - = create_subprog_decl - (get_identifier ("__builtin_update_setjmp_buf"), NULL_TREE, - build_function_type_list (void_type_node, jmpbuf_ptr_type, NULL_TREE), - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - set_decl_built_in_function (update_setjmp_buf_decl, BUILT_IN_NORMAL, - BUILT_IN_UPDATE_SETJMP_BUF); - - /* Indicate that it never returns. */ - ftype = build_function_type_list (void_type_node, - build_pointer_type (except_type_node), - NULL_TREE); - ftype = build_qualified_type (ftype, TYPE_QUAL_VOLATILE); - raise_nodefer_decl - = create_subprog_decl - (get_identifier ("__gnat_raise_nodefer_with_msg"), NULL_TREE, ftype, - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - - set_exception_parameter_decl - = create_subprog_decl - (get_identifier ("__gnat_set_exception_parameter"), NULL_TREE, - build_function_type_list (void_type_node, ptr_type_node, ptr_type_node, - NULL_TREE), - NULL_TREE, is_default, true, true, true, false, false, NULL, Empty); - - /* Hooks to call when entering/leaving an exception handler. */ - ftype = build_function_type_list (ptr_type_node, - ptr_type_node, NULL_TREE); - begin_handler_decl - = create_subprog_decl (get_identifier ("__gnat_begin_handler_v1"), - NULL_TREE, ftype, NULL_TREE, - is_default, true, true, true, false, false, NULL, - Empty); - /* __gnat_begin_handler_v1 is not a dummy procedure, but we arrange - for it not to throw. */ - TREE_NOTHROW (begin_handler_decl) = 1; - - ftype = build_function_type_list (ptr_type_node, - ptr_type_node, ptr_type_node, - ptr_type_node, NULL_TREE); - end_handler_decl - = create_subprog_decl (get_identifier ("__gnat_end_handler_v1"), NULL_TREE, - ftype, NULL_TREE, - is_default, true, true, true, false, false, NULL, - Empty); - - ftype = build_function_type_list (void_type_node, ptr_type_node, NULL_TREE); - unhandled_except_decl - = create_subprog_decl (get_identifier ("__gnat_unhandled_except_handler"), - NULL_TREE, ftype, NULL_TREE, - is_default, true, true, true, false, false, NULL, - Empty); - - /* Indicate that it never returns. */ - ftype = build_qualified_type (ftype, TYPE_QUAL_VOLATILE); - reraise_zcx_decl - = create_subprog_decl (get_identifier ("__gnat_reraise_zcx"), NULL_TREE, - ftype, NULL_TREE, - is_default, true, true, true, false, false, NULL, - Empty); - - /* Dummy objects to materialize "others" and "all others" in the exception - tables. These are exported by a-exexpr-gcc.adb, so see this unit for - the types to use. */ - others_decl - = create_var_decl (get_identifier ("OTHERS"), - get_identifier ("__gnat_others_value"), - char_type_node, NULL_TREE, - true, false, true, false, false, true, false, - NULL, Empty); - - all_others_decl - = create_var_decl (get_identifier ("ALL_OTHERS"), - get_identifier ("__gnat_all_others_value"), - char_type_node, NULL_TREE, - true, false, true, false, false, true, false, - NULL, Empty); - - unhandled_others_decl - = create_var_decl (get_identifier ("UNHANDLED_OTHERS"), - get_identifier ("__gnat_unhandled_others_value"), - char_type_node, NULL_TREE, - true, false, true, false, false, true, false, - NULL, Empty); - - /* If in no exception handlers mode, all raise statements are redirected to - __gnat_last_chance_handler. No need to redefine raise_nodefer_decl since - this procedure will never be called in this mode. */ - if (No_Exception_Handlers_Set ()) - { - /* Indicate that it never returns. */ - ftype = build_function_type_list (void_type_node, - build_pointer_type (char_type_node), - integer_type_node, NULL_TREE); - ftype = build_qualified_type (ftype, TYPE_QUAL_VOLATILE); - tree decl - = create_subprog_decl - (get_identifier ("__gnat_last_chance_handler"), NULL_TREE, ftype, - NULL_TREE, is_default, true, true, true, false, false, NULL, - Empty); - for (i = 0; i < (int) ARRAY_SIZE (gnat_raise_decls); i++) - gnat_raise_decls[i] = decl; - } - else - { - /* Otherwise, make one decl for each exception reason. */ - for (i = 0; i < (int) ARRAY_SIZE (gnat_raise_decls); i++) - gnat_raise_decls[i] = build_raise_check (i, exception_simple); - for (i = 0; i < (int) ARRAY_SIZE (gnat_raise_decls_ext); i++) - gnat_raise_decls_ext[i] - = build_raise_check (i, - i == CE_Index_Check_Failed - || i == CE_Range_Check_Failed - || i == CE_Invalid_Data - ? exception_range : exception_column); - } - - /* Build the special descriptor type and its null node if needed. */ - if (TARGET_VTABLE_USES_DESCRIPTORS) - { - tree null_node = fold_convert (ptr_void_ftype, null_pointer_node); - tree field_list = NULL_TREE; - int j; - vec<constructor_elt, va_gc> *null_vec = NULL; - constructor_elt *elt; - - fdesc_type_node = make_node (RECORD_TYPE); - vec_safe_grow (null_vec, TARGET_VTABLE_USES_DESCRIPTORS, true); - elt = (null_vec->address () + TARGET_VTABLE_USES_DESCRIPTORS - 1); - - for (j = 0; j < TARGET_VTABLE_USES_DESCRIPTORS; j++) - { - tree field - = create_field_decl (NULL_TREE, ptr_void_ftype, fdesc_type_node, - NULL_TREE, NULL_TREE, 0, 1); - DECL_CHAIN (field) = field_list; - field_list = field; - elt->index = field; - elt->value = null_node; - elt--; - } - - finish_record_type (fdesc_type_node, nreverse (field_list), 0, false); - record_builtin_type ("descriptor", fdesc_type_node, true); - null_fdesc_node = gnat_build_constructor (fdesc_type_node, null_vec); - } - - longest_float_type_node - = get_unpadded_type (Base_Type (standard_long_long_float)); - - main_identifier_node = get_identifier ("main"); - - /* If we are using the GCC exception mechanism, let GCC know. */ - if (Back_End_Exceptions ()) - gnat_init_gcc_eh (); - - /* Initialize the GCC support for FP operations. */ - gnat_init_gcc_fp (); - - /* Install the builtins we might need, either internally or as user-available - facilities for Intrinsic imports. Note that this must be done after the - GCC exception mechanism is initialized. */ - gnat_install_builtins (); - - vec_safe_push (gnu_except_ptr_stack, NULL_TREE); - - gnu_constraint_error_label_stack.safe_push (Empty); - gnu_storage_error_label_stack.safe_push (Empty); - gnu_program_error_label_stack.safe_push (Empty); - - /* Process any Pragma Ident for the main unit. */ - if (Present (Ident_String (Main_Unit))) - targetm.asm_out.output_ident - (TREE_STRING_POINTER (gnat_to_gnu (Ident_String (Main_Unit)))); - - /* Force -fno-strict-aliasing if the configuration pragma was seen. */ - if (No_Strict_Aliasing_CP) - flag_strict_aliasing = 0; - - /* Save the current optimization options again after the above possible - global_options changes. */ - optimization_default_node - = build_optimization_node (&global_options, &global_options_set); - optimization_current_node = optimization_default_node; - - /* Now translate the compilation unit proper. */ - Compilation_Unit_to_gnu (gnat_root); - - /* Then process the N_Validate_Unchecked_Conversion nodes. We do this at - the very end to avoid having to second-guess the front-end when we run - into dummy nodes during the regular processing. */ - for (i = 0; gnat_validate_uc_list.iterate (i, &gnat_iter); i++) - validate_unchecked_conversion (gnat_iter); - gnat_validate_uc_list.release (); - - /* Finally see if we have any elaboration procedures to deal with. */ - for (info = elab_info_list; info; info = info->next) - { - tree gnu_body = DECL_SAVED_TREE (info->elab_proc); - - /* We should have a BIND_EXPR but it may not have any statements in it. - If it doesn't have any, we have nothing to do except for setting the - flag on the GNAT node. Otherwise, process the function as others. */ - tree gnu_stmts = gnu_body; - if (TREE_CODE (gnu_stmts) == BIND_EXPR) - gnu_stmts = BIND_EXPR_BODY (gnu_stmts); - if (!gnu_stmts || empty_stmt_list_p (gnu_stmts)) - Set_Has_No_Elaboration_Code (info->gnat_node, 1); - else - { - begin_subprog_body (info->elab_proc); - end_subprog_body (gnu_body); - rest_of_subprog_body_compilation (info->elab_proc); - } - } - - /* Destroy ourselves. */ - file_map = NULL; - destroy_gnat_decl (); - destroy_gnat_utils (); - - /* We cannot track the location of errors past this point. */ - Current_Error_Node = Empty; -} - -/* Return a subprogram decl corresponding to __gnat_rcheck_xx for the given - CHECK if KIND is EXCEPTION_SIMPLE, or else to __gnat_rcheck_xx_ext. */ - -static tree -build_raise_check (int check, enum exception_info_kind kind) -{ - tree result, ftype; - const char pfx[] = "__gnat_rcheck_"; - - strcpy (Name_Buffer, pfx); - Name_Len = sizeof (pfx) - 1; - Get_RT_Exception_Name ((enum RT_Exception_Code) check); - - if (kind == exception_simple) - { - Name_Buffer[Name_Len] = 0; - ftype - = build_function_type_list (void_type_node, - build_pointer_type (char_type_node), - integer_type_node, NULL_TREE); - } - else - { - tree t = (kind == exception_column ? NULL_TREE : integer_type_node); - - strcpy (Name_Buffer + Name_Len, "_ext"); - Name_Buffer[Name_Len + 4] = 0; - ftype - = build_function_type_list (void_type_node, - build_pointer_type (char_type_node), - integer_type_node, integer_type_node, - t, t, NULL_TREE); - } - - /* Indicate that it never returns. */ - ftype = build_qualified_type (ftype, TYPE_QUAL_VOLATILE); - result - = create_subprog_decl (get_identifier (Name_Buffer), NULL_TREE, ftype, - NULL_TREE, is_default, true, true, true, false, - false, NULL, Empty); - - return result; -} - -/* Return a positive value if an lvalue is required for GNAT_NODE, which is - an N_Attribute_Reference. */ - -static int -lvalue_required_for_attribute_p (Node_Id gnat_node) -{ - switch (Get_Attribute_Id (Attribute_Name (gnat_node))) - { - case Attr_Pred: - case Attr_Succ: - case Attr_First: - case Attr_Last: - case Attr_Range_Length: - case Attr_Length: - case Attr_Object_Size: - case Attr_Size: - case Attr_Value_Size: - case Attr_Component_Size: - case Attr_Descriptor_Size: - case Attr_Max_Size_In_Storage_Elements: - case Attr_Min: - case Attr_Max: - case Attr_Null_Parameter: - case Attr_Passed_By_Reference: - case Attr_Mechanism_Code: - case Attr_Machine: - case Attr_Model: - return 0; - - case Attr_Address: - case Attr_Access: - case Attr_Unchecked_Access: - case Attr_Unrestricted_Access: - case Attr_Code_Address: - case Attr_Pool_Address: - case Attr_Alignment: - case Attr_Bit_Position: - case Attr_Position: - case Attr_First_Bit: - case Attr_Last_Bit: - case Attr_Bit: - case Attr_Asm_Input: - case Attr_Asm_Output: - default: - return 1; - } -} - -/* Return a positive value if an lvalue is required for GNAT_NODE. GNU_TYPE - is the type that will be used for GNAT_NODE in the translated GNU tree. - CONSTANT indicates whether the underlying object represented by GNAT_NODE - is constant in the Ada sense. If it is, ADDRESS_OF_CONSTANT indicates - whether its value is the address of another constant. If it isn't, then - ADDRESS_OF_CONSTANT is ignored. - - The function climbs up the GNAT tree starting from the node and returns 1 - upon encountering a node that effectively requires an lvalue downstream. - It returns int instead of bool to facilitate usage in non-purely binary - logic contexts. */ - -static int -lvalue_required_p (Node_Id gnat_node, tree gnu_type, bool constant, - bool address_of_constant) -{ - Node_Id gnat_parent = Parent (gnat_node), gnat_temp; - - switch (Nkind (gnat_parent)) - { - case N_Reference: - return 1; - - case N_Attribute_Reference: - return lvalue_required_for_attribute_p (gnat_parent); - - case N_Parameter_Association: - case N_Function_Call: - case N_Procedure_Call_Statement: - /* If the parameter is by reference, an lvalue is required. */ - return (!constant - || must_pass_by_ref (gnu_type) - || default_pass_by_ref (gnu_type)); - - case N_Pragma_Argument_Association: - return lvalue_required_p (gnat_parent, gnu_type, constant, - address_of_constant); - - case N_Pragma: - if (Is_Pragma_Name (Chars (Pragma_Identifier (gnat_parent)))) - { - const unsigned char id - = Get_Pragma_Id (Chars (Pragma_Identifier (gnat_parent))); - return id == Pragma_Inspection_Point; - } - else - return 0; - - case N_Indexed_Component: - /* Only the array expression can require an lvalue. */ - if (Prefix (gnat_parent) != gnat_node) - return 0; - - /* ??? Consider that referencing an indexed component with a variable - index forces the whole aggregate to memory. Note that testing only - for literals is conservative, any static expression in the RM sense - could probably be accepted with some additional work. */ - for (gnat_temp = First (Expressions (gnat_parent)); - Present (gnat_temp); - gnat_temp = Next (gnat_temp)) - if (Nkind (gnat_temp) != N_Character_Literal - && Nkind (gnat_temp) != N_Integer_Literal - && !(Is_Entity_Name (gnat_temp) - && Ekind (Entity (gnat_temp)) == E_Enumeration_Literal)) - return 1; - - /* ... fall through ... */ - - case N_Selected_Component: - case N_Slice: - /* Only the prefix expression can require an lvalue. */ - if (Prefix (gnat_parent) != gnat_node) - return 0; - - return lvalue_required_p (gnat_parent, - get_unpadded_type (Etype (gnat_parent)), - constant, address_of_constant); - - case N_Object_Renaming_Declaration: - /* We need to preserve addresses through a renaming. */ - return 1; - - case N_Object_Declaration: - /* We cannot use a constructor if this is an atomic object because - the actual assignment might end up being done component-wise. */ - return (!constant - ||(Is_Composite_Type (Underlying_Type (Etype (gnat_node))) - && Is_Full_Access (Defining_Entity (gnat_parent))) - /* We don't use a constructor if this is a class-wide object - because the effective type of the object is the equivalent - type of the class-wide subtype and it smashes most of the - data into an array of bytes to which we cannot convert. */ - || Ekind ((Etype (Defining_Entity (gnat_parent)))) - == E_Class_Wide_Subtype); - - case N_Assignment_Statement: - /* We cannot use a constructor if the LHS is an atomic object because - the actual assignment might end up being done component-wise. */ - return (!constant - || Name (gnat_parent) == gnat_node - || (Is_Composite_Type (Underlying_Type (Etype (gnat_node))) - && Is_Entity_Name (Name (gnat_parent)) - && Is_Full_Access (Entity (Name (gnat_parent))))); - - case N_Unchecked_Type_Conversion: - if (!constant) - return 1; - - /* ... fall through ... */ - - case N_Type_Conversion: - case N_Qualified_Expression: - /* We must look through all conversions because we may need to bypass - an intermediate conversion that is meant to be purely formal. */ - return lvalue_required_p (gnat_parent, - get_unpadded_type (Etype (gnat_parent)), - constant, address_of_constant); - - case N_Explicit_Dereference: - /* We look through dereferences for address of constant because we need - to handle the special cases listed above. */ - if (constant && address_of_constant) - return lvalue_required_p (gnat_parent, - get_unpadded_type (Etype (gnat_parent)), - true, false); - - /* ... fall through ... */ - - default: - return 0; - } - - gcc_unreachable (); -} - -/* Return true if an lvalue should be used for GNAT_NODE. GNU_TYPE is the type - that will be used for GNAT_NODE in the translated GNU tree and is assumed to - be an aggregate type. - - The function climbs up the GNAT tree starting from the node and returns true - upon encountering a node that makes it doable to decide. lvalue_required_p - should have been previously invoked on the arguments and returned false. */ - -static bool -lvalue_for_aggregate_p (Node_Id gnat_node, tree gnu_type) -{ - Node_Id gnat_parent = Parent (gnat_node); - - switch (Nkind (gnat_parent)) - { - case N_Parameter_Association: - case N_Function_Call: - case N_Procedure_Call_Statement: - /* Even if the parameter is by copy, prefer an lvalue. */ - return true; - - case N_Simple_Return_Statement: - /* Likewise for a return value. */ - return true; - - case N_Indexed_Component: - case N_Selected_Component: - /* If an elementary component is used, take it from the constant. */ - if (!Is_Composite_Type (Underlying_Type (Etype (gnat_parent)))) - return false; - - /* ... fall through ... */ - - case N_Slice: - return lvalue_for_aggregate_p (gnat_parent, - get_unpadded_type (Etype (gnat_parent))); - - case N_Object_Declaration: - /* For an aggregate object declaration, return false consistently. */ - return false; - - case N_Assignment_Statement: - /* For an aggregate assignment, decide based on the size. */ - { - const HOST_WIDE_INT size = int_size_in_bytes (gnu_type); - return size < 0 || size >= param_large_stack_frame / 4; - } - - case N_Unchecked_Type_Conversion: - case N_Type_Conversion: - case N_Qualified_Expression: - return lvalue_for_aggregate_p (gnat_parent, - get_unpadded_type (Etype (gnat_parent))); - - case N_Allocator: - /* We should only reach here through the N_Qualified_Expression case. - Force an lvalue for aggregate types since a block-copy to the newly - allocated area of memory is made. */ - return true; - - default: - return false; - } - - gcc_unreachable (); -} - - -/* Return true if T is a constant DECL node that can be safely replaced - by its initializer. */ - -static bool -constant_decl_with_initializer_p (tree t) -{ - if (!TREE_CONSTANT (t) || !DECL_P (t) || !DECL_INITIAL (t)) - return false; - - /* Return false for aggregate types that contain a placeholder since - their initializers cannot be manipulated easily. */ - if (AGGREGATE_TYPE_P (TREE_TYPE (t)) - && !TYPE_IS_FAT_POINTER_P (TREE_TYPE (t)) - && type_contains_placeholder_p (TREE_TYPE (t))) - return false; - - return true; -} - -/* Return an expression equivalent to EXP but where constant DECL nodes - have been replaced by their initializer. */ - -static tree -fold_constant_decl_in_expr (tree exp) -{ - enum tree_code code = TREE_CODE (exp); - tree op0; - - switch (code) - { - case CONST_DECL: - case VAR_DECL: - if (!constant_decl_with_initializer_p (exp)) - return exp; - - return DECL_INITIAL (exp); - - case COMPONENT_REF: - op0 = fold_constant_decl_in_expr (TREE_OPERAND (exp, 0)); - if (op0 == TREE_OPERAND (exp, 0)) - return exp; - - return fold_build3 (COMPONENT_REF, TREE_TYPE (exp), op0, - TREE_OPERAND (exp, 1), NULL_TREE); - - case BIT_FIELD_REF: - op0 = fold_constant_decl_in_expr (TREE_OPERAND (exp, 0)); - if (op0 == TREE_OPERAND (exp, 0)) - return exp; - - return fold_build3 (BIT_FIELD_REF, TREE_TYPE (exp), op0, - TREE_OPERAND (exp, 1), TREE_OPERAND (exp, 2)); - - case ARRAY_REF: - case ARRAY_RANGE_REF: - /* If the index is not itself constant, then nothing can be folded. */ - if (!TREE_CONSTANT (TREE_OPERAND (exp, 1))) - return exp; - op0 = fold_constant_decl_in_expr (TREE_OPERAND (exp, 0)); - if (op0 == TREE_OPERAND (exp, 0)) - return exp; - - return fold (build4 (code, TREE_TYPE (exp), op0, TREE_OPERAND (exp, 1), - TREE_OPERAND (exp, 2), NULL_TREE)); - - case REALPART_EXPR: - case IMAGPART_EXPR: - case VIEW_CONVERT_EXPR: - op0 = fold_constant_decl_in_expr (TREE_OPERAND (exp, 0)); - if (op0 == TREE_OPERAND (exp, 0)) - return exp; - - return fold_build1 (code, TREE_TYPE (exp), op0); - - default: - return exp; - } - - gcc_unreachable (); -} - -/* Return true if TYPE and DEF_TYPE are compatible GNAT types for Gigi. */ - -static bool -Gigi_Types_Compatible (Entity_Id type, Entity_Id def_type) -{ - /* The trivial case. */ - if (type == def_type) - return true; - - /* A class-wide type is equivalent to a subtype of itself. */ - if (Is_Class_Wide_Type (type)) - return true; - - /* A packed array type is compatible with its implementation type. */ - if (Is_Packed (def_type) && type == Packed_Array_Impl_Type (def_type)) - return true; - - /* If both types are Itypes, one may be a copy of the other. */ - if (Is_Itype (def_type) && Is_Itype (type)) - return true; - - /* If the type is incomplete and comes from a limited context, then also - consider its non-limited view. */ - if (Is_Incomplete_Type (def_type) - && From_Limited_With (def_type) - && Present (Non_Limited_View (def_type))) - return Gigi_Types_Compatible (type, Non_Limited_View (def_type)); - - /* If the type is incomplete/private, then also consider its full view. */ - if (Is_Incomplete_Or_Private_Type (def_type) - && Present (Full_View (def_type))) - return Gigi_Types_Compatible (type, Full_View (def_type)); - - return false; -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, an N_Identifier, - to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer - to where we should place the result type. */ - -static tree -Identifier_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p) -{ - /* The entity of GNAT_NODE and its type. */ - Node_Id gnat_entity = (Nkind (gnat_node) == N_Defining_Identifier - || Nkind (gnat_node) == N_Defining_Operator_Symbol) - ? gnat_node : Entity (gnat_node); - Node_Id gnat_entity_type = Etype (gnat_entity); - /* If GNAT_NODE is a constant, whether we should use the initialization - value instead of the constant entity, typically for scalars with an - address clause when the parent doesn't require an lvalue. */ - bool use_constant_initializer = false; - /* Whether we should require an lvalue for GNAT_NODE. Needed in - specific circumstances only, so evaluated lazily. < 0 means - unknown, > 0 means known true, 0 means known false. */ - int require_lvalue = -1; - Entity_Id gnat_result_type; - tree gnu_result, gnu_result_type; - - /* If the Etype of this node is not the same as that of the Entity, then - something went wrong, probably in generic instantiation. However, this - does not apply to types. Since we sometime have strange Ekind's, just - do this test for objects, except for discriminants because their type - may have been changed to a subtype by Exp_Ch3.Adjust_Discriminants. */ - gcc_assert (!Is_Object (gnat_entity) - || Ekind (gnat_entity) == E_Discriminant - || Etype (gnat_node) == gnat_entity_type - || Gigi_Types_Compatible (Etype (gnat_node), gnat_entity_type)); - - /* If this is a reference to a deferred constant whose partial view is an - unconstrained private type, the proper type is on the full view of the - constant, not on the full view of the type, which may be unconstrained. - - This may be a reference to a type, for example in the prefix of the - attribute Position, generated for dispatching code (see Make_DT in - exp_disp,adb). In that case we need the type itself, not is parent, - in particular if it is a derived type */ - if (Ekind (gnat_entity) == E_Constant - && Is_Private_Type (gnat_entity_type) - && (Has_Unknown_Discriminants (gnat_entity_type) - || (Present (Full_View (gnat_entity_type)) - && Has_Discriminants (Full_View (gnat_entity_type)))) - && Present (Full_View (gnat_entity))) - { - gnat_entity = Full_View (gnat_entity); - gnat_result_type = Etype (gnat_entity); - } - else - { - /* We use the Actual_Subtype only if it has already been elaborated, - as we may be invoked precisely during its elaboration, otherwise - the Etype. Avoid using it for packed arrays to simplify things, - except in a return statement because we need the actual size and - the front-end does not make it explicit in this case. */ - if ((Ekind (gnat_entity) == E_Constant - || Ekind (gnat_entity) == E_Variable - || Is_Formal (gnat_entity)) - && !(Is_Array_Type (Etype (gnat_entity)) - && Present (Packed_Array_Impl_Type (Etype (gnat_entity))) - && Nkind (Parent (gnat_node)) != N_Simple_Return_Statement) - && Present (Actual_Subtype (gnat_entity)) - && present_gnu_tree (Actual_Subtype (gnat_entity))) - gnat_result_type = Actual_Subtype (gnat_entity); - else - gnat_result_type = Etype (gnat_node); - } - - /* Expand the type of this identifier first, in case it is an enumeral - literal, which only get made when the type is expanded. There is no - order-of-elaboration issue here. */ - gnu_result_type = get_unpadded_type (gnat_result_type); - - /* If this is a non-imported elementary constant with an address clause, - retrieve the value instead of a pointer to be dereferenced unless - an lvalue is required. This is generally more efficient and actually - required if this is a static expression because it might be used - in a context where a dereference is inappropriate, such as a case - statement alternative or a record discriminant. There is no possible - volatile-ness short-circuit here since Volatile constants must be - imported per C.6. */ - if (Ekind (gnat_entity) == E_Constant - && Is_Elementary_Type (gnat_result_type) - && !Is_Imported (gnat_entity) - && Present (Address_Clause (gnat_entity))) - { - require_lvalue - = lvalue_required_p (gnat_node, gnu_result_type, true, false); - use_constant_initializer = !require_lvalue; - } - - if (use_constant_initializer) - { - /* If this is a deferred constant, the initializer is attached to - the full view. */ - if (Present (Full_View (gnat_entity))) - gnat_entity = Full_View (gnat_entity); - - gnu_result = gnat_to_gnu (Expression (Declaration_Node (gnat_entity))); - } - else - gnu_result = gnat_to_gnu_entity (gnat_entity, NULL_TREE, false); - - /* Some objects (such as parameters passed by reference, globals of - variable size, and renamed objects) actually represent the address - of the object. In that case, we must do the dereference. Likewise, - deal with parameters to foreign convention subprograms. */ - if (DECL_P (gnu_result) - && (DECL_BY_REF_P (gnu_result) - || (TREE_CODE (gnu_result) == PARM_DECL - && DECL_BY_COMPONENT_PTR_P (gnu_result)))) - { - const bool read_only = DECL_POINTS_TO_READONLY_P (gnu_result); - - /* If it's a PARM_DECL to foreign convention subprogram, convert it. */ - if (TREE_CODE (gnu_result) == PARM_DECL - && DECL_BY_COMPONENT_PTR_P (gnu_result)) - gnu_result - = convert (build_pointer_type (gnu_result_type), gnu_result); - - /* If it's a CONST_DECL, return the underlying constant like below. */ - else if (TREE_CODE (gnu_result) == CONST_DECL - && !(DECL_CONST_ADDRESS_P (gnu_result) - && lvalue_required_p (gnat_node, gnu_result_type, true, - true))) - gnu_result = DECL_INITIAL (gnu_result); - - /* Do the final dereference. */ - gnu_result = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_result); - - if ((TREE_CODE (gnu_result) == INDIRECT_REF - || TREE_CODE (gnu_result) == UNCONSTRAINED_ARRAY_REF) - && No (Address_Clause (gnat_entity))) - TREE_THIS_NOTRAP (gnu_result) = 1; - - if (read_only) - TREE_READONLY (gnu_result) = 1; - } - - /* If we have a constant declaration and its initializer, try to return the - latter to avoid the need to call fold in lots of places and the need for - elaboration code if this identifier is used as an initializer itself. */ - if (constant_decl_with_initializer_p (gnu_result)) - { - bool constant_only = (TREE_CODE (gnu_result) == CONST_DECL - && !DECL_CONST_CORRESPONDING_VAR (gnu_result)); - bool address_of_constant = (TREE_CODE (gnu_result) == CONST_DECL - && DECL_CONST_ADDRESS_P (gnu_result)); - - /* If there is a (corresponding) variable or this is the address of a - constant, we only want to return the initializer if an lvalue isn't - required. Evaluate this now if we have not already done so. */ - if ((!constant_only || address_of_constant) && require_lvalue < 0) - require_lvalue - = lvalue_required_p (gnat_node, gnu_result_type, true, - address_of_constant) - || (AGGREGATE_TYPE_P (gnu_result_type) - && lvalue_for_aggregate_p (gnat_node, gnu_result_type)); - - /* Finally retrieve the initializer if this is deemed valid. */ - if ((constant_only && !address_of_constant) || !require_lvalue) - gnu_result = DECL_INITIAL (gnu_result); - } - - /* But for a constant renaming we couldn't do that incrementally for its - definition because of the need to return an lvalue so, if the present - context doesn't itself require an lvalue, we try again here. */ - else if (Ekind (gnat_entity) == E_Constant - && Is_Elementary_Type (gnat_result_type) - && Present (Renamed_Object (gnat_entity))) - { - if (require_lvalue < 0) - require_lvalue - = lvalue_required_p (gnat_node, gnu_result_type, true, false); - if (!require_lvalue) - gnu_result = fold_constant_decl_in_expr (gnu_result); - } - - /* The GNAT tree has the type of a function set to its result type, so we - adjust here. Also use the type of the result if the Etype is a subtype - that is nominally unconstrained. Likewise if this is a deferred constant - of a discriminated type whose full view can be elaborated statically, to - avoid problematic conversions to the nominal subtype. But remove any - padding from the resulting type. */ - if (FUNC_OR_METHOD_TYPE_P (TREE_TYPE (gnu_result)) - || Is_Constr_Subt_For_UN_Aliased (gnat_result_type) - || (Ekind (gnat_entity) == E_Constant - && Present (Full_View (gnat_entity)) - && Has_Discriminants (gnat_result_type) - && TREE_CODE (gnu_result) == CONSTRUCTOR)) - { - gnu_result_type = TREE_TYPE (gnu_result); - if (TYPE_IS_PADDING_P (gnu_result_type)) - gnu_result_type = TREE_TYPE (TYPE_FIELDS (gnu_result_type)); - } - - *gnu_result_type_p = gnu_result_type; - - return gnu_result; -} - -/* Subroutine of gnat_to_gnu to process gnat_node, an N_Pragma. Return - any statements we generate. */ - -static tree -Pragma_to_gnu (Node_Id gnat_node) -{ - tree gnu_result = alloc_stmt_list (); - Node_Id gnat_temp; - - /* Check for (and ignore) unrecognized pragmas. */ - if (!Is_Pragma_Name (Chars (Pragma_Identifier (gnat_node)))) - return gnu_result; - - const unsigned char id - = Get_Pragma_Id (Chars (Pragma_Identifier (gnat_node))); - - /* Save the expression of pragma Compile_Time_{Error|Warning} for later. */ - if (id == Pragma_Compile_Time_Error || id == Pragma_Compile_Time_Warning) - { - gnat_temp = First (Pragma_Argument_Associations (gnat_node)); - gnat_compile_time_expr_list.safe_push (Expression (gnat_temp)); - return gnu_result; - } - - /* Stop there if we are just annotating types. */ - if (type_annotate_only) - return gnu_result; - - switch (id) - { - case Pragma_Inspection_Point: - /* Do nothing at top level: all such variables are already viewable. */ - if (global_bindings_p ()) - break; - - for (gnat_temp = First (Pragma_Argument_Associations (gnat_node)); - Present (gnat_temp); - gnat_temp = Next (gnat_temp)) - { - Node_Id gnat_expr = Expression (gnat_temp); - tree gnu_expr = gnat_to_gnu (gnat_expr); - tree asm_constraint = NULL_TREE; -#ifdef ASM_COMMENT_START - char *comment; -#endif - gnu_expr = maybe_unconstrained_array (gnu_expr); - if (TREE_CODE (gnu_expr) == CONST_DECL - && DECL_CONST_CORRESPONDING_VAR (gnu_expr)) - gnu_expr = DECL_CONST_CORRESPONDING_VAR (gnu_expr); - gnat_mark_addressable (gnu_expr); - -#ifdef ASM_COMMENT_START - comment = concat (ASM_COMMENT_START, - " inspection point: ", - Get_Name_String (Chars (gnat_expr)), - " is at %0", - NULL); - asm_constraint = build_string (strlen (comment), comment); - free (comment); -#endif - gnu_expr = build5 (ASM_EXPR, void_type_node, - asm_constraint, - NULL_TREE, - tree_cons - (build_tree_list (NULL_TREE, - build_string (1, "m")), - gnu_expr, NULL_TREE), - NULL_TREE, NULL_TREE); - ASM_VOLATILE_P (gnu_expr) = 1; - set_expr_location_from_node (gnu_expr, gnat_node); - append_to_statement_list (gnu_expr, &gnu_result); - } - break; - - case Pragma_Loop_Optimize: - for (gnat_temp = First (Pragma_Argument_Associations (gnat_node)); - Present (gnat_temp); - gnat_temp = Next (gnat_temp)) - { - tree gnu_loop_stmt = gnu_loop_stack->last ()->stmt; - - switch (Chars (Expression (gnat_temp))) - { - case Name_Ivdep: - LOOP_STMT_IVDEP (gnu_loop_stmt) = 1; - break; - - case Name_No_Unroll: - LOOP_STMT_NO_UNROLL (gnu_loop_stmt) = 1; - break; - - case Name_Unroll: - LOOP_STMT_UNROLL (gnu_loop_stmt) = 1; - break; - - case Name_No_Vector: - LOOP_STMT_NO_VECTOR (gnu_loop_stmt) = 1; - break; - - case Name_Vector: - LOOP_STMT_VECTOR (gnu_loop_stmt) = 1; - break; - - default: - gcc_unreachable (); - } - } - break; - - case Pragma_Optimize: - switch (Chars (Expression - (First (Pragma_Argument_Associations (gnat_node))))) - { - case Name_Off: - if (optimize) - post_error ("must specify -O0??", gnat_node); - break; - - case Name_Space: - if (!optimize_size) - post_error ("must specify -Os??", gnat_node); - break; - - case Name_Time: - if (!optimize) - post_error ("insufficient -O value??", gnat_node); - break; - - default: - gcc_unreachable (); - } - break; - - case Pragma_Reviewable: - if (write_symbols == NO_DEBUG) - post_error ("must specify -g??", gnat_node); - break; - - case Pragma_Warning_As_Error: - case Pragma_Warnings: - { - Node_Id gnat_expr; - /* Preserve the location of the pragma. */ - const location_t location = input_location; - struct cl_option_handlers handlers; - unsigned int option_index; - diagnostic_t kind; - bool imply; - - gnat_temp = First (Pragma_Argument_Associations (gnat_node)); - - /* This is the String form: pragma Warning{s|_As_Error}(String). */ - if (Nkind (Expression (gnat_temp)) == N_String_Literal) - { - switch (id) - { - case Pragma_Warning_As_Error: - kind = DK_ERROR; - imply = false; - break; - - case Pragma_Warnings: - kind = DK_WARNING; - imply = true; - break; - - default: - gcc_unreachable (); - } - - gnat_expr = Expression (gnat_temp); - } - - /* This is the On/Off form: pragma Warnings (On | Off [,String]). */ - else if (Nkind (Expression (gnat_temp)) == N_Identifier) - { - switch (Chars (Expression (gnat_temp))) - { - case Name_Off: - kind = DK_IGNORED; - break; - - case Name_On: - kind = DK_WARNING; - break; - - default: - gcc_unreachable (); - } - - /* Deal with optional pattern (but ignore Reason => "..."). */ - if (Present (Next (gnat_temp)) - && Chars (Next (gnat_temp)) != Name_Reason) - { - /* pragma Warnings (On | Off, Name) is handled differently. */ - if (Nkind (Expression (Next (gnat_temp))) != N_String_Literal) - break; - - gnat_expr = Expression (Next (gnat_temp)); - } - else - { - gnat_expr = Empty; - - /* For pragma Warnings (Off), we save the current state... */ - if (kind == DK_IGNORED) - diagnostic_push_diagnostics (global_dc, location); - - /* ...so that, for pragma Warnings (On), we do not enable all - the warnings but just restore the previous state. */ - else - { - diagnostic_pop_diagnostics (global_dc, location); - break; - } - } - - imply = false; - } - - else - gcc_unreachable (); - - /* This is the same implementation as in the C family of compilers. */ - const unsigned int lang_mask = CL_Ada | CL_COMMON; - const char *arg = NULL; - if (Present (gnat_expr)) - { - tree gnu_expr = gnat_to_gnu (gnat_expr); - const char *option_string = TREE_STRING_POINTER (gnu_expr); - const int len = TREE_STRING_LENGTH (gnu_expr); - if (len < 3 || option_string[0] != '-' || option_string[1] != 'W') - break; - option_index = find_opt (option_string + 1, lang_mask); - if (option_index == OPT_SPECIAL_unknown) - { - post_error ("unknown -W switch??", gnat_node); - break; - } - else if (!(cl_options[option_index].flags & CL_WARNING)) - { - post_error ("-W switch does not control warning??", gnat_node); - break; - } - else if (!(cl_options[option_index].flags & lang_mask)) - { - post_error ("-W switch not valid for Ada??", gnat_node); - break; - } - if (cl_options[option_index].flags & CL_JOINED) - arg = option_string + 1 + cl_options[option_index].opt_len; - } - else - option_index = 0; - - set_default_handlers (&handlers, NULL); - control_warning_option (option_index, (int) kind, arg, imply, location, - lang_mask, &handlers, &global_options, - &global_options_set, global_dc); - } - break; - - default: - break; - } - - return gnu_result; -} - -/* Check the inline status of nested function FNDECL wrt its parent function. - - If a non-inline nested function is referenced from an inline external - function, we cannot honor both requests at the same time without cloning - the nested function in the current unit since it is private to its unit. - We could inline it as well but it's probably better to err on the side - of too little inlining. - - This must be done only on nested functions present in the source code - and not on nested functions generated by the compiler, e.g. finalizers, - because they may be not marked inline and we don't want them to block - the inlining of the parent function. */ - -static void -check_inlining_for_nested_subprog (tree fndecl) -{ - if (DECL_IGNORED_P (current_function_decl) || DECL_IGNORED_P (fndecl)) - return; - - if (DECL_DECLARED_INLINE_P (fndecl)) - return; - - tree parent_decl = decl_function_context (fndecl); - if (DECL_EXTERNAL (parent_decl) && DECL_DECLARED_INLINE_P (parent_decl)) - { - const location_t loc1 = DECL_SOURCE_LOCATION (fndecl); - const location_t loc2 = DECL_SOURCE_LOCATION (parent_decl); - - if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (parent_decl))) - { - error_at (loc1, "subprogram %q+F not marked %<Inline_Always%>", - fndecl); - error_at (loc2, "parent subprogram cannot be inlined"); - } - else - { - warning_at (loc1, OPT_Winline, "subprogram %q+F not marked %<Inline%>", - fndecl); - warning_at (loc2, OPT_Winline, "parent subprogram cannot be inlined"); - } - - DECL_DECLARED_INLINE_P (parent_decl) = 0; - DECL_UNINLINABLE (parent_decl) = 1; - } -} - -/* Return an expression for the length of TYPE, an integral type, computed in - RESULT_TYPE, another integral type. - - We used to compute the length as MAX (hb - lb + 1, 0) which could overflow - when lb == TYPE'First. We now compute it as (hb >= lb) ? hb - lb + 1 : 0 - which would only overflow in much rarer cases, for extremely large arrays - we expect never to encounter in practice. Besides, the former computation - required the use of potentially constraining signed arithmetics while the - latter does not. Note that the comparison must be done in the original - base index type in order to avoid any overflow during the conversion. */ - -static tree -get_type_length (tree type, tree result_type) -{ - tree comp_type = get_base_type (result_type); - tree base_type = maybe_character_type (get_base_type (type)); - tree lb = convert (base_type, TYPE_MIN_VALUE (type)); - tree hb = convert (base_type, TYPE_MAX_VALUE (type)); - tree length - = build_binary_op (PLUS_EXPR, comp_type, - build_binary_op (MINUS_EXPR, comp_type, - convert (comp_type, hb), - convert (comp_type, lb)), - build_int_cst (comp_type, 1)); - length - = build_cond_expr (result_type, - build_binary_op (GE_EXPR, boolean_type_node, hb, lb), - convert (result_type, length), - build_int_cst (result_type, 0)); - return length; -} - -/* Subroutine of gnat_to_gnu to translate GNAT_NODE, an N_Attribute node, - to a GCC tree, which is returned. GNU_RESULT_TYPE_P is a pointer to - where we should place the result type. ATTRIBUTE is the attribute ID. */ - -static tree -Attribute_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p, int attribute) -{ - const Node_Id gnat_prefix = Prefix (gnat_node); - tree gnu_prefix = gnat_to_gnu (gnat_prefix); - tree gnu_type = TREE_TYPE (gnu_prefix); - tree gnu_expr, gnu_result_type, gnu_result = error_mark_node; - bool prefix_unused = false; - - /* If the input is a NULL_EXPR, make a new one. */ - if (TREE_CODE (gnu_prefix) == NULL_EXPR) - { - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - *gnu_result_type_p = gnu_result_type; - return build1 (NULL_EXPR, gnu_result_type, TREE_OPERAND (gnu_prefix, 0)); - } - - switch (attribute) - { - case Attr_Pred: - case Attr_Succ: - /* These just add or subtract the constant 1 since representation - clauses for enumeration types are handled in the front-end. */ - gnu_expr = gnat_to_gnu (First (Expressions (gnat_node))); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_type = maybe_character_type (gnu_result_type); - if (TREE_TYPE (gnu_expr) != gnu_type) - gnu_expr = convert (gnu_type, gnu_expr); - gnu_result - = build_binary_op (attribute == Attr_Pred ? MINUS_EXPR : PLUS_EXPR, - gnu_type, gnu_expr, build_int_cst (gnu_type, 1)); - break; - - case Attr_Address: - case Attr_Unrestricted_Access: - /* Conversions don't change the address of references but can cause - build_unary_op to miss the references below, so strip them off. - On the contrary, if the address-of operation causes a temporary - to be created, then it must be created with the proper type. */ - gnu_expr = remove_conversions (gnu_prefix, - !Must_Be_Byte_Aligned (gnat_node)); - if (REFERENCE_CLASS_P (gnu_expr)) - gnu_prefix = gnu_expr; - - /* If we are taking 'Address of an unconstrained object, this is the - pointer to the underlying array. */ - if (attribute == Attr_Address) - gnu_prefix = maybe_unconstrained_array (gnu_prefix); - - /* If we are building a static dispatch table, we have to honor - TARGET_VTABLE_USES_DESCRIPTORS if we want to be compatible - with the C++ ABI. We do it in the non-static case as well, - see gnat_to_gnu_entity, case E_Access_Subprogram_Type. */ - else if (TARGET_VTABLE_USES_DESCRIPTORS - && Is_Dispatch_Table_Entity (Etype (gnat_node))) - { - tree gnu_field, t; - /* Descriptors can only be built here for top-level functions. */ - bool build_descriptor = (global_bindings_p () != 0); - int i; - vec<constructor_elt, va_gc> *gnu_vec = NULL; - constructor_elt *elt; - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If we're not going to build the descriptor, we have to retrieve - the one which will be built by the linker (or by the compiler - later if a static chain is requested). */ - if (!build_descriptor) - { - gnu_result = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_prefix); - gnu_result = fold_convert (build_pointer_type (gnu_result_type), - gnu_result); - gnu_result = build1 (INDIRECT_REF, gnu_result_type, gnu_result); - } - - vec_safe_grow (gnu_vec, TARGET_VTABLE_USES_DESCRIPTORS, true); - elt = (gnu_vec->address () + TARGET_VTABLE_USES_DESCRIPTORS - 1); - for (gnu_field = TYPE_FIELDS (gnu_result_type), i = 0; - i < TARGET_VTABLE_USES_DESCRIPTORS; - gnu_field = DECL_CHAIN (gnu_field), i++) - { - if (build_descriptor) - { - t = build2 (FDESC_EXPR, TREE_TYPE (gnu_field), gnu_prefix, - build_int_cst (NULL_TREE, i)); - TREE_CONSTANT (t) = 1; - } - else - t = build3 (COMPONENT_REF, ptr_void_ftype, gnu_result, - gnu_field, NULL_TREE); - - elt->index = gnu_field; - elt->value = t; - elt--; - } - - gnu_result = gnat_build_constructor (gnu_result_type, gnu_vec); - break; - } - - /* ... fall through ... */ - - case Attr_Access: - case Attr_Unchecked_Access: - case Attr_Code_Address: - /* Taking the address of a type does not make sense. */ - gcc_assert (TREE_CODE (gnu_prefix) != TYPE_DECL); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result - = build_unary_op (((attribute == Attr_Address - || attribute == Attr_Unrestricted_Access) - && !Must_Be_Byte_Aligned (gnat_node)) - ? ATTR_ADDR_EXPR : ADDR_EXPR, - gnu_result_type, gnu_prefix); - - /* For 'Code_Address, find an inner ADDR_EXPR and mark it so that we - don't try to build a trampoline. */ - if (attribute == Attr_Code_Address) - { - gnu_expr = remove_conversions (gnu_result, false); - - if (TREE_CODE (gnu_expr) == ADDR_EXPR) - TREE_NO_TRAMPOLINE (gnu_expr) = TREE_CONSTANT (gnu_expr) = 1; - - /* On targets for which function symbols denote a descriptor, the - code address is stored within the first slot of the descriptor - so we do an additional dereference: - result = *((result_type *) result) - where we expect result to be of some pointer type already. */ - if (targetm.calls.custom_function_descriptors == 0) - gnu_result - = build_unary_op (INDIRECT_REF, NULL_TREE, - convert (build_pointer_type (gnu_result_type), - gnu_result)); - } - - /* For 'Access, issue an error message if the prefix is a C++ method - since it can use a special calling convention on some platforms, - which cannot be propagated to the access type. */ - else if (attribute == Attr_Access - && TREE_CODE (TREE_TYPE (gnu_prefix)) == METHOD_TYPE) - post_error ("access to C++ constructor or member function not allowed", - gnat_node); - - /* For other address attributes applied to a nested function, - find an inner ADDR_EXPR and annotate it so that we can issue - a useful warning with -Wtrampolines. */ - else if (FUNC_OR_METHOD_TYPE_P (TREE_TYPE (gnu_prefix)) - && (gnu_expr = remove_conversions (gnu_result, false)) - && TREE_CODE (gnu_expr) == ADDR_EXPR - && decl_function_context (TREE_OPERAND (gnu_expr, 0))) - { - set_expr_location_from_node (gnu_expr, gnat_node); - - /* Also check the inlining status. */ - check_inlining_for_nested_subprog (TREE_OPERAND (gnu_expr, 0)); - - /* Moreover, for 'Access or 'Unrestricted_Access with non- - foreign-compatible representation, mark the ADDR_EXPR so - that we can build a descriptor instead of a trampoline. */ - if ((attribute == Attr_Access - || attribute == Attr_Unrestricted_Access) - && targetm.calls.custom_function_descriptors > 0 - && Can_Use_Internal_Rep (Underlying_Type (Etype (gnat_node)))) - FUNC_ADDR_BY_DESCRIPTOR (gnu_expr) = 1; - - /* Otherwise, we need to check that we are not violating the - No_Implicit_Dynamic_Code restriction. */ - else if (targetm.calls.custom_function_descriptors != 0) - Check_Implicit_Dynamic_Code_Allowed (gnat_node); - } - break; - - case Attr_Pool_Address: - { - tree gnu_ptr = gnu_prefix; - tree gnu_obj_type; - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If this is fat pointer, the object must have been allocated with the - template in front of the array. So compute the template address; do - it by converting to a thin pointer. */ - if (TYPE_IS_FAT_POINTER_P (TREE_TYPE (gnu_ptr))) - gnu_ptr - = convert (build_pointer_type - (TYPE_OBJECT_RECORD_TYPE - (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (gnu_ptr)))), - gnu_ptr); - - gnu_obj_type = TREE_TYPE (TREE_TYPE (gnu_ptr)); - - /* If this is a thin pointer, the object must have been allocated with - the template in front of the array. So compute the template address - and return it. */ - if (TYPE_IS_THIN_POINTER_P (TREE_TYPE (gnu_ptr))) - gnu_ptr - = build_binary_op (POINTER_PLUS_EXPR, TREE_TYPE (gnu_ptr), - gnu_ptr, - fold_build1 (NEGATE_EXPR, sizetype, - byte_position - (DECL_CHAIN - TYPE_FIELDS ((gnu_obj_type))))); - - gnu_result = convert (gnu_result_type, gnu_ptr); - } - break; - - case Attr_Size: - case Attr_Object_Size: - case Attr_Value_Size: - case Attr_Max_Size_In_Storage_Elements: - /* Strip NOPs, conversions between original and packable versions, and - unpadding from GNU_PREFIX. Note that we cannot simply strip every - VIEW_CONVERT_EXPR because some of them may give the actual size, e.g. - for nominally unconstrained packed array. We use GNU_EXPR to see - if a COMPONENT_REF was involved. */ - while (CONVERT_EXPR_P (gnu_prefix) - || TREE_CODE (gnu_prefix) == NON_LVALUE_EXPR - || (TREE_CODE (gnu_prefix) == VIEW_CONVERT_EXPR - && TREE_CODE (TREE_TYPE (gnu_prefix)) == RECORD_TYPE - && TREE_CODE (TREE_TYPE (TREE_OPERAND (gnu_prefix, 0))) - == RECORD_TYPE - && TYPE_NAME (TREE_TYPE (gnu_prefix)) - == TYPE_NAME (TREE_TYPE (TREE_OPERAND (gnu_prefix, 0))))) - gnu_prefix = TREE_OPERAND (gnu_prefix, 0); - gnu_expr = gnu_prefix; - if (TREE_CODE (gnu_prefix) == COMPONENT_REF - && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_prefix, 0)))) - gnu_prefix = TREE_OPERAND (gnu_prefix, 0); - prefix_unused = true; - gnu_type = TREE_TYPE (gnu_prefix); - - /* Replace an unconstrained array type with the type of the underlying - array, except for 'Max_Size_In_Storage_Elements because we need to - return the (maximum) size requested for an allocator. */ - if (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE) - { - gnu_type = TYPE_OBJECT_RECORD_TYPE (gnu_type); - if (attribute != Attr_Max_Size_In_Storage_Elements) - gnu_type = TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (gnu_type))); - } - - /* The type must be frozen at this point. */ - gcc_assert (COMPLETE_TYPE_P (gnu_type)); - - /* If we're looking for the size of a field, return the field size. */ - if (TREE_CODE (gnu_prefix) == COMPONENT_REF) - gnu_result = DECL_SIZE (TREE_OPERAND (gnu_prefix, 1)); - - /* Otherwise, if the prefix is an object, or if we are looking for - 'Object_Size or 'Max_Size_In_Storage_Elements, the result is the - GCC size of the type. We make an exception for padded objects, - as we do not take into account alignment promotions for the size. - This is in keeping with the object case of gnat_to_gnu_entity. */ - else if ((TREE_CODE (gnu_prefix) != TYPE_DECL - && !(TYPE_IS_PADDING_P (gnu_type) - && TREE_CODE (gnu_expr) == COMPONENT_REF - && pad_type_has_rm_size (gnu_type))) - || attribute == Attr_Object_Size - || attribute == Attr_Max_Size_In_Storage_Elements) - { - /* If this is a dereference and we have a special dynamic constrained - subtype on the prefix, use it to compute the size; otherwise, use - the designated subtype. */ - if (Nkind (gnat_prefix) == N_Explicit_Dereference) - { - Node_Id gnat_actual_subtype - = Actual_Designated_Subtype (gnat_prefix); - tree gnu_ptr_type - = TREE_TYPE (gnat_to_gnu (Prefix (gnat_prefix))); - - if (TYPE_IS_FAT_OR_THIN_POINTER_P (gnu_ptr_type) - && Present (gnat_actual_subtype)) - { - tree gnu_actual_obj_type - = gnat_to_gnu_type (gnat_actual_subtype); - gnu_type - = build_unc_object_type_from_ptr (gnu_ptr_type, - gnu_actual_obj_type, - get_identifier ("SIZE"), - false); - } - } - - gnu_result = TYPE_SIZE (gnu_type); - } - - /* Otherwise, the result is the RM size of the type. */ - else - gnu_result = rm_size (gnu_type); - - /* Deal with a self-referential size by qualifying the size with the - object or returning the maximum size for a type. */ - if (TREE_CODE (gnu_prefix) != TYPE_DECL) - gnu_result = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_result, gnu_prefix); - else if (CONTAINS_PLACEHOLDER_P (gnu_result)) - gnu_result = max_size (gnu_result, true); - - /* If the type contains a template, subtract the padded size of the - template, except for 'Max_Size_In_Storage_Elements because we need - to return the (maximum) size requested for an allocator. */ - if (TREE_CODE (gnu_type) == RECORD_TYPE - && TYPE_CONTAINS_TEMPLATE_P (gnu_type) - && attribute != Attr_Max_Size_In_Storage_Elements) - gnu_result - = size_binop (MINUS_EXPR, gnu_result, - bit_position (DECL_CHAIN (TYPE_FIELDS (gnu_type)))); - - /* For 'Max_Size_In_Storage_Elements, adjust the unit. */ - if (attribute == Attr_Max_Size_In_Storage_Elements) - gnu_result = size_binop (CEIL_DIV_EXPR, gnu_result, bitsize_unit_node); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - break; - - case Attr_Alignment: - { - unsigned int align; - - if (TREE_CODE (gnu_prefix) == COMPONENT_REF - && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_prefix, 0)))) - gnu_prefix = TREE_OPERAND (gnu_prefix, 0); - - gnu_type = TREE_TYPE (gnu_prefix); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - prefix_unused = true; - - if (TREE_CODE (gnu_prefix) == COMPONENT_REF) - align = DECL_ALIGN (TREE_OPERAND (gnu_prefix, 1)) / BITS_PER_UNIT; - else - { - Entity_Id gnat_type = Etype (gnat_prefix); - unsigned int double_align; - bool is_capped_double, align_clause; - - /* If the default alignment of "double" or larger scalar types is - specifically capped and there is an alignment clause neither - on the type nor on the prefix itself, return the cap. */ - if ((double_align = double_float_alignment) > 0) - is_capped_double - = is_double_float_or_array (gnat_type, &align_clause); - else if ((double_align = double_scalar_alignment) > 0) - is_capped_double - = is_double_scalar_or_array (gnat_type, &align_clause); - else - is_capped_double = align_clause = false; - - if (is_capped_double - && Nkind (gnat_prefix) == N_Identifier - && Present (Alignment_Clause (Entity (gnat_prefix)))) - align_clause = true; - - if (is_capped_double && !align_clause) - align = double_align; - else - align = TYPE_ALIGN (gnu_type) / BITS_PER_UNIT; - } - - gnu_result = size_int (align); - } - break; - - case Attr_First: - case Attr_Last: - case Attr_Range_Length: - prefix_unused = true; - - if (INTEGRAL_TYPE_P (gnu_type) || SCALAR_FLOAT_TYPE_P (gnu_type)) - { - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - if (attribute == Attr_First) - gnu_result = TYPE_MIN_VALUE (gnu_type); - else if (attribute == Attr_Last) - gnu_result = TYPE_MAX_VALUE (gnu_type); - else - gnu_result = get_type_length (gnu_type, gnu_result_type); - break; - } - - /* ... fall through ... */ - - case Attr_Length: - { - int Dimension = (Present (Expressions (gnat_node)) - ? UI_To_Int (Intval (First (Expressions (gnat_node)))) - : 1), i; - struct parm_attr_d *pa = NULL; - Entity_Id gnat_param = Empty; - bool unconstrained_ptr_deref = false; - - gnu_prefix = maybe_padded_object (gnu_prefix); - gnu_prefix = maybe_unconstrained_array (gnu_prefix); - - /* We treat unconstrained array In parameters specially. We also note - whether we are dereferencing a pointer to unconstrained array. */ - if (!Is_Constrained (Etype (gnat_prefix))) - switch (Nkind (gnat_prefix)) - { - case N_Identifier: - /* This is the direct case. */ - if (Ekind (Entity (gnat_prefix)) == E_In_Parameter) - gnat_param = Entity (gnat_prefix); - break; - - case N_Explicit_Dereference: - /* This is the indirect case. Note that we need to be sure that - the access value cannot be null as we'll hoist the load. */ - if (Nkind (Prefix (gnat_prefix)) == N_Identifier - && Ekind (Entity (Prefix (gnat_prefix))) == E_In_Parameter) - { - if (Can_Never_Be_Null (Entity (Prefix (gnat_prefix)))) - gnat_param = Entity (Prefix (gnat_prefix)); - } - else - unconstrained_ptr_deref = true; - break; - - default: - break; - } - - /* If the prefix is the view conversion of a constrained array to an - unconstrained form, we retrieve the constrained array because we - might not be able to substitute the PLACEHOLDER_EXPR coming from - the conversion. This can occur with the 'Old attribute applied - to a parameter with an unconstrained type, which gets rewritten - into a constrained local variable very late in the game. */ - if (TREE_CODE (gnu_prefix) == VIEW_CONVERT_EXPR - && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (TREE_TYPE (gnu_prefix))) - && !CONTAINS_PLACEHOLDER_P - (TYPE_SIZE (TREE_TYPE (TREE_OPERAND (gnu_prefix, 0))))) - gnu_type = TREE_TYPE (TREE_OPERAND (gnu_prefix, 0)); - else - gnu_type = TREE_TYPE (gnu_prefix); - - prefix_unused = true; - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - if (TYPE_CONVENTION_FORTRAN_P (gnu_type)) - { - int ndim; - tree gnu_type_temp; - - for (ndim = 1, gnu_type_temp = gnu_type; - TREE_CODE (TREE_TYPE (gnu_type_temp)) == ARRAY_TYPE - && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_type_temp)); - ndim++, gnu_type_temp = TREE_TYPE (gnu_type_temp)) - ; - - Dimension = ndim + 1 - Dimension; - } - - for (i = 1; i < Dimension; i++) - gnu_type = TREE_TYPE (gnu_type); - - gcc_assert (TREE_CODE (gnu_type) == ARRAY_TYPE); - - /* When not optimizing, look up the slot associated with the parameter - and the dimension in the cache and create a new one on failure. - Don't do this when the actual subtype needs debug info (this happens - with -gnatD): in elaborate_expression_1, we create variables that - hold the bounds, so caching attributes isn't very interesting and - causes dependency issues between these variables and cached - expressions. */ - if (!optimize - && Present (gnat_param) - && !(Present (Actual_Subtype (gnat_param)) - && Needs_Debug_Info (Actual_Subtype (gnat_param)))) - { - FOR_EACH_VEC_SAFE_ELT (f_parm_attr_cache, i, pa) - if (pa->id == gnat_param && pa->dim == Dimension) - break; - - if (!pa) - { - pa = ggc_cleared_alloc<parm_attr_d> (); - pa->id = gnat_param; - pa->dim = Dimension; - vec_safe_push (f_parm_attr_cache, pa); - } - } - - /* Return the cached expression or build a new one. */ - if (attribute == Attr_First) - { - if (pa && pa->first) - { - gnu_result = pa->first; - break; - } - - gnu_result - = TYPE_MIN_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (gnu_type))); - } - - else if (attribute == Attr_Last) - { - if (pa && pa->last) - { - gnu_result = pa->last; - break; - } - - gnu_result - = TYPE_MAX_VALUE (TYPE_INDEX_TYPE (TYPE_DOMAIN (gnu_type))); - } - - else /* attribute == Attr_Range_Length || attribute == Attr_Length */ - { - if (pa && pa->length) - { - gnu_result = pa->length; - break; - } - - gnu_result - = get_type_length (TYPE_INDEX_TYPE (TYPE_DOMAIN (gnu_type)), - gnu_result_type); - } - - /* If this has a PLACEHOLDER_EXPR, qualify it by the object we are - handling. Note that these attributes could not have been used on - an unconstrained array type. */ - gnu_result = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_result, gnu_prefix); - - /* Cache the expression we have just computed. Since we want to do it - at run time, we force the use of a SAVE_EXPR and let the gimplifier - create the temporary in the outermost binding level. We will make - sure in Subprogram_Body_to_gnu that it is evaluated on all possible - paths by forcing its evaluation on entry of the function. */ - if (pa) - { - gnu_result - = build1 (SAVE_EXPR, TREE_TYPE (gnu_result), gnu_result); - switch (attribute) - { - case Attr_First: - pa->first = gnu_result; - break; - - case Attr_Last: - pa->last = gnu_result; - break; - - case Attr_Length: - case Attr_Range_Length: - pa->length = gnu_result; - break; - - default: - gcc_unreachable (); - } - } - - /* Otherwise, evaluate it each time it is referenced. */ - else - switch (attribute) - { - case Attr_First: - case Attr_Last: - /* If we are dereferencing a pointer to unconstrained array, we - need to capture the value because the pointed-to bounds may - subsequently be released. */ - if (unconstrained_ptr_deref) - gnu_result - = build1 (SAVE_EXPR, TREE_TYPE (gnu_result), gnu_result); - break; - - case Attr_Length: - case Attr_Range_Length: - /* Set the source location onto the predicate of the condition - but not if the expression is cached to avoid messing up the - debug info. */ - if (TREE_CODE (gnu_result) == COND_EXPR - && EXPR_P (TREE_OPERAND (gnu_result, 0))) - set_expr_location_from_node (TREE_OPERAND (gnu_result, 0), - gnat_node); - break; - - default: - gcc_unreachable (); - } - - break; - } - - case Attr_Bit_Position: - case Attr_Position: - case Attr_First_Bit: - case Attr_Last_Bit: - case Attr_Bit: - { - poly_int64 bitsize; - poly_int64 bitpos; - tree gnu_offset; - tree gnu_field_bitpos; - tree gnu_field_offset; - tree gnu_inner; - machine_mode mode; - int unsignedp, reversep, volatilep; - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_prefix = remove_conversions (gnu_prefix, true); - prefix_unused = true; - - /* We can have 'Bit on any object, but if it isn't a COMPONENT_REF, - the result is 0. Don't allow 'Bit on a bare component, though. */ - if (attribute == Attr_Bit - && TREE_CODE (gnu_prefix) != COMPONENT_REF - && TREE_CODE (gnu_prefix) != FIELD_DECL) - { - gnu_result = integer_zero_node; - break; - } - - else - gcc_assert (TREE_CODE (gnu_prefix) == COMPONENT_REF - || (attribute == Attr_Bit_Position - && TREE_CODE (gnu_prefix) == FIELD_DECL)); - - get_inner_reference (gnu_prefix, &bitsize, &bitpos, &gnu_offset, - &mode, &unsignedp, &reversep, &volatilep); - - if (TREE_CODE (gnu_prefix) == COMPONENT_REF) - { - gnu_field_bitpos = bit_position (TREE_OPERAND (gnu_prefix, 1)); - gnu_field_offset = byte_position (TREE_OPERAND (gnu_prefix, 1)); - - for (gnu_inner = TREE_OPERAND (gnu_prefix, 0); - TREE_CODE (gnu_inner) == COMPONENT_REF - && DECL_INTERNAL_P (TREE_OPERAND (gnu_inner, 1)); - gnu_inner = TREE_OPERAND (gnu_inner, 0)) - { - gnu_field_bitpos - = size_binop (PLUS_EXPR, gnu_field_bitpos, - bit_position (TREE_OPERAND (gnu_inner, 1))); - gnu_field_offset - = size_binop (PLUS_EXPR, gnu_field_offset, - byte_position (TREE_OPERAND (gnu_inner, 1))); - } - } - else if (TREE_CODE (gnu_prefix) == FIELD_DECL) - { - gnu_field_bitpos = bit_position (gnu_prefix); - gnu_field_offset = byte_position (gnu_prefix); - } - else - { - gnu_field_bitpos = bitsize_zero_node; - gnu_field_offset = size_zero_node; - } - - switch (attribute) - { - case Attr_Position: - gnu_result = gnu_field_offset; - break; - - case Attr_First_Bit: - case Attr_Bit: - gnu_result = size_int (num_trailing_bits (bitpos)); - break; - - case Attr_Last_Bit: - gnu_result = bitsize_int (num_trailing_bits (bitpos)); - gnu_result = size_binop (PLUS_EXPR, gnu_result, - TYPE_SIZE (TREE_TYPE (gnu_prefix))); - /* ??? Avoid a large unsigned result that will overflow when - converted to the signed universal_integer. */ - if (integer_zerop (gnu_result)) - gnu_result = integer_minus_one_node; - else - gnu_result - = size_binop (MINUS_EXPR, gnu_result, bitsize_one_node); - break; - - case Attr_Bit_Position: - gnu_result = gnu_field_bitpos; - break; - } - - /* If this has a PLACEHOLDER_EXPR, qualify it by the object we are - handling. */ - gnu_result = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_result, gnu_prefix); - break; - } - - case Attr_Min: - case Attr_Max: - { - tree gnu_lhs = gnat_to_gnu (First (Expressions (gnat_node))); - tree gnu_rhs = gnat_to_gnu (Next (First (Expressions (gnat_node)))); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* The result of {MIN,MAX}_EXPR is unspecified if either operand is - a NaN so we implement the semantics of C99 f{min,max} to make it - predictable in this case: if either operand is a NaN, the other - is returned; if both operands are NaN's, a NaN is returned. */ - if (SCALAR_FLOAT_TYPE_P (gnu_result_type) - && !Machine_Overflows_On_Target) - { - const bool lhs_side_effects_p = TREE_SIDE_EFFECTS (gnu_lhs); - const bool rhs_side_effects_p = TREE_SIDE_EFFECTS (gnu_rhs); - tree t = builtin_decl_explicit (BUILT_IN_ISNAN); - tree lhs_is_nan, rhs_is_nan; - - /* If the operands have side-effects, they need to be evaluated - only once in spite of the multiple references in the result. */ - if (lhs_side_effects_p) - gnu_lhs = gnat_protect_expr (gnu_lhs); - if (rhs_side_effects_p) - gnu_rhs = gnat_protect_expr (gnu_rhs); - - lhs_is_nan = fold_build2 (NE_EXPR, boolean_type_node, - build_call_expr (t, 1, gnu_lhs), - integer_zero_node); - - rhs_is_nan = fold_build2 (NE_EXPR, boolean_type_node, - build_call_expr (t, 1, gnu_rhs), - integer_zero_node); - - gnu_result = build_binary_op (attribute == Attr_Min - ? MIN_EXPR : MAX_EXPR, - gnu_result_type, gnu_lhs, gnu_rhs); - gnu_result = fold_build3 (COND_EXPR, gnu_result_type, - rhs_is_nan, gnu_lhs, gnu_result); - gnu_result = fold_build3 (COND_EXPR, gnu_result_type, - lhs_is_nan, gnu_rhs, gnu_result); - - /* If the operands have side-effects, they need to be evaluated - before doing the tests above since the place they otherwise - would end up being evaluated at run time could be wrong. */ - if (lhs_side_effects_p) - gnu_result - = build2 (COMPOUND_EXPR, gnu_result_type, gnu_lhs, gnu_result); - - if (rhs_side_effects_p) - gnu_result - = build2 (COMPOUND_EXPR, gnu_result_type, gnu_rhs, gnu_result); - } - else - gnu_result = build_binary_op (attribute == Attr_Min - ? MIN_EXPR : MAX_EXPR, - gnu_result_type, gnu_lhs, gnu_rhs); - } - break; - - case Attr_Passed_By_Reference: - gnu_result = size_int (default_pass_by_ref (gnu_type) - || must_pass_by_ref (gnu_type)); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - break; - - case Attr_Component_Size: - gnu_prefix = maybe_padded_object (gnu_prefix); - gnu_type = TREE_TYPE (gnu_prefix); - - if (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE) - gnu_type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_type)))); - - while (TREE_CODE (TREE_TYPE (gnu_type)) == ARRAY_TYPE - && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_type))) - gnu_type = TREE_TYPE (gnu_type); - - gcc_assert (TREE_CODE (gnu_type) == ARRAY_TYPE); - - /* Note this size cannot be self-referential. */ - gnu_result = TYPE_SIZE (TREE_TYPE (gnu_type)); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - prefix_unused = true; - break; - - case Attr_Descriptor_Size: - gnu_type = TREE_TYPE (gnu_prefix); - gcc_assert (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE); - - /* Return the padded size of the template in the object record type. */ - gnu_type = TYPE_OBJECT_RECORD_TYPE (gnu_type); - gnu_result = bit_position (DECL_CHAIN (TYPE_FIELDS (gnu_type))); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - prefix_unused = true; - break; - - case Attr_Null_Parameter: - /* This is just a zero cast to the pointer type for our prefix and - dereferenced. */ - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result - = build_unary_op (INDIRECT_REF, NULL_TREE, - convert (build_pointer_type (gnu_result_type), - integer_zero_node)); - break; - - case Attr_Mechanism_Code: - { - Entity_Id gnat_obj = Entity (gnat_prefix); - int code; - - prefix_unused = true; - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - if (Present (Expressions (gnat_node))) - { - int i = UI_To_Int (Intval (First (Expressions (gnat_node)))); - - for (gnat_obj = First_Formal (gnat_obj); i > 1; - i--, gnat_obj = Next_Formal (gnat_obj)) - ; - } - - code = Mechanism (gnat_obj); - if (code == Default) - code = ((present_gnu_tree (gnat_obj) - && (DECL_BY_REF_P (get_gnu_tree (gnat_obj)) - || ((TREE_CODE (get_gnu_tree (gnat_obj)) - == PARM_DECL) - && (DECL_BY_COMPONENT_PTR_P - (get_gnu_tree (gnat_obj)))))) - ? By_Reference : By_Copy); - gnu_result = convert (gnu_result_type, size_int (- code)); - } - break; - - case Attr_Model: - /* We treat Model as identical to Machine. This is true for at least - IEEE and some other nice floating-point systems. */ - - /* ... fall through ... */ - - case Attr_Machine: - /* The trick is to force the compiler to store the result in memory so - that we do not have extra precision used. But do this only when this - is necessary, i.e. if FP_ARITH_MAY_WIDEN is true and the precision of - the type is lower than that of the longest floating-point type. */ - prefix_unused = true; - gnu_expr = gnat_to_gnu (First (Expressions (gnat_node))); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result = convert (gnu_result_type, gnu_expr); - - if (TREE_CODE (gnu_result) != REAL_CST - && fp_arith_may_widen - && TYPE_PRECISION (gnu_result_type) - < TYPE_PRECISION (longest_float_type_node)) - { - tree rec_type = make_node (RECORD_TYPE); - tree field - = create_field_decl (get_identifier ("OBJ"), gnu_result_type, - rec_type, NULL_TREE, NULL_TREE, 0, 0); - tree rec_val, asm_expr; - - finish_record_type (rec_type, field, 0, false); - - rec_val = build_constructor_single (rec_type, field, gnu_result); - rec_val = build1 (SAVE_EXPR, rec_type, rec_val); - - asm_expr - = build5 (ASM_EXPR, void_type_node, - build_string (0, ""), - tree_cons (build_tree_list (NULL_TREE, - build_string (2, "=m")), - rec_val, NULL_TREE), - tree_cons (build_tree_list (NULL_TREE, - build_string (1, "m")), - rec_val, NULL_TREE), - NULL_TREE, NULL_TREE); - ASM_VOLATILE_P (asm_expr) = 1; - - gnu_result - = build_compound_expr (gnu_result_type, asm_expr, - build_component_ref (rec_val, field, - false)); - } - break; - - case Attr_Deref: - prefix_unused = true; - gnu_expr = gnat_to_gnu (First (Expressions (gnat_node))); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - /* This can be a random address so build an alias-all pointer type. */ - gnu_expr - = convert (build_pointer_type_for_mode (gnu_result_type, ptr_mode, - true), - gnu_expr); - gnu_result = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_expr); - break; - - default: - /* This abort means that we have an unimplemented attribute. */ - gcc_unreachable (); - } - - /* If this is an attribute where the prefix was unused, force a use of it if - it has a side-effect. But don't do it if the prefix is just an entity - name. However, if an access check is needed, we must do it. See second - example in AARM 11.6(5.e). */ - if (prefix_unused - && TREE_SIDE_EFFECTS (gnu_prefix) - && !Is_Entity_Name (gnat_prefix)) - gnu_result - = build_compound_expr (TREE_TYPE (gnu_result), gnu_prefix, gnu_result); - - *gnu_result_type_p = gnu_result_type; - return gnu_result; -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, an N_Case_Statement, - to a GCC tree, which is returned. */ - -static tree -Case_Statement_to_gnu (Node_Id gnat_node) -{ - tree gnu_result, gnu_expr, gnu_type, gnu_label; - Node_Id gnat_when; - location_t end_locus; - bool may_fallthru = false; - - gnu_expr = gnat_to_gnu (Expression (gnat_node)); - gnu_expr = convert (get_base_type (TREE_TYPE (gnu_expr)), gnu_expr); - gnu_expr = maybe_character_value (gnu_expr); - gnu_type = TREE_TYPE (gnu_expr); - - /* We build a SWITCH_EXPR that contains the code with interspersed - CASE_LABEL_EXPRs for each label. */ - if (!Sloc_to_locus (End_Location (gnat_node), &end_locus)) - end_locus = input_location; - gnu_label = create_artificial_label (end_locus); - start_stmt_group (); - - for (gnat_when = First_Non_Pragma (Alternatives (gnat_node)); - Present (gnat_when); - gnat_when = Next_Non_Pragma (gnat_when)) - { - bool choices_added_p = false; - Node_Id gnat_choice; - - /* First compile all the different case choices for the current WHEN - alternative. */ - for (gnat_choice = First (Discrete_Choices (gnat_when)); - Present (gnat_choice); - gnat_choice = Next (gnat_choice)) - { - tree gnu_low = NULL_TREE, gnu_high = NULL_TREE; - tree label = create_artificial_label (input_location); - - switch (Nkind (gnat_choice)) - { - case N_Range: - gnu_low = gnat_to_gnu (Low_Bound (gnat_choice)); - gnu_high = gnat_to_gnu (High_Bound (gnat_choice)); - break; - - case N_Subtype_Indication: - gnu_low = gnat_to_gnu (Low_Bound (Range_Expression - (Constraint (gnat_choice)))); - gnu_high = gnat_to_gnu (High_Bound (Range_Expression - (Constraint (gnat_choice)))); - break; - - case N_Identifier: - case N_Expanded_Name: - /* This represents either a subtype range or a static value of - some kind; Ekind says which. */ - if (Is_Type (Entity (gnat_choice))) - { - tree gnu_type = get_unpadded_type (Entity (gnat_choice)); - - gnu_low = TYPE_MIN_VALUE (gnu_type); - gnu_high = TYPE_MAX_VALUE (gnu_type); - break; - } - - /* ... fall through ... */ - - case N_Character_Literal: - case N_Integer_Literal: - gnu_low = gnat_to_gnu (gnat_choice); - break; - - case N_Others_Choice: - break; - - default: - gcc_unreachable (); - } - - /* Everything should be folded into constants at this point. */ - gcc_assert (!gnu_low || TREE_CODE (gnu_low) == INTEGER_CST); - gcc_assert (!gnu_high || TREE_CODE (gnu_high) == INTEGER_CST); - - if (gnu_low && TREE_TYPE (gnu_low) != gnu_type) - gnu_low = convert (gnu_type, gnu_low); - if (gnu_high && TREE_TYPE (gnu_high) != gnu_type) - gnu_high = convert (gnu_type, gnu_high); - - add_stmt_with_node (build_case_label (gnu_low, gnu_high, label), - gnat_choice); - choices_added_p = true; - } - - /* This construct doesn't define a scope so we shouldn't push a binding - level around the statement list. Except that we have always done so - historically and this makes it possible to reduce stack usage. As a - compromise, we keep doing it for case statements, for which this has - never been problematic, but not for case expressions in Ada 2012. */ - if (choices_added_p) - { - const bool is_case_expression - = (Nkind (Parent (gnat_node)) == N_Expression_With_Actions); - tree group - = build_stmt_group (Statements (gnat_when), !is_case_expression); - bool group_may_fallthru = block_may_fallthru (group); - add_stmt (group); - if (group_may_fallthru) - { - tree stmt = build1 (GOTO_EXPR, void_type_node, gnu_label); - SET_EXPR_LOCATION (stmt, end_locus); - add_stmt (stmt); - may_fallthru = true; - } - } - } - - /* Now emit a definition of the label the cases branch to, if any. */ - if (may_fallthru) - add_stmt (build1 (LABEL_EXPR, void_type_node, gnu_label)); - gnu_result = build2 (SWITCH_EXPR, gnu_type, gnu_expr, end_stmt_group ()); - - return gnu_result; -} - -/* Return true if we are in the body of a loop. */ - -static inline bool -inside_loop_p (void) -{ - return !vec_safe_is_empty (gnu_loop_stack); -} - -/* Find out whether EXPR is a simple additive expression based on the iteration - variable of some enclosing loop in the current function. If so, return the - loop and set *DISP to the displacement and *NEG_P to true if this is for a - subtraction; otherwise, return NULL. */ - -static struct loop_info_d * -find_loop_for (tree expr, tree *disp, bool *neg_p) -{ - tree var, add, cst; - bool minus_p; - struct loop_info_d *iter = NULL; - unsigned int i; - - if (is_simple_additive_expression (expr, &add, &cst, &minus_p)) - { - var = add; - if (disp) - *disp = cst; - if (neg_p) - *neg_p = minus_p; - } - else - { - var = expr; - if (disp) - *disp = NULL_TREE; - if (neg_p) - *neg_p = false; - } - - var = remove_conversions (var, false); - - if (TREE_CODE (var) != VAR_DECL) - return NULL; - - gcc_checking_assert (vec_safe_length (gnu_loop_stack) > 0); - - FOR_EACH_VEC_ELT_REVERSE (*gnu_loop_stack, i, iter) - if (iter->loop_var == var && iter->fndecl == current_function_decl) - break; - - return iter; -} - -/* Return the innermost enclosing loop in the current function. */ - -static struct loop_info_d * -find_loop (void) -{ - struct loop_info_d *iter = NULL; - unsigned int i; - - gcc_checking_assert (vec_safe_length (gnu_loop_stack) > 0); - - FOR_EACH_VEC_ELT_REVERSE (*gnu_loop_stack, i, iter) - if (iter->fndecl == current_function_decl) - break; - - return iter; -} - -/* Return true if VAL (of type TYPE) can equal the minimum value if MAX is - false, or the maximum value if MAX is true, of TYPE. */ - -static bool -can_equal_min_or_max_val_p (tree val, tree type, bool max) -{ - tree min_or_max_val = (max ? TYPE_MAX_VALUE (type) : TYPE_MIN_VALUE (type)); - - if (TREE_CODE (min_or_max_val) != INTEGER_CST) - return true; - - if (TREE_CODE (val) == NOP_EXPR) - val = (max - ? TYPE_MAX_VALUE (TREE_TYPE (TREE_OPERAND (val, 0))) - : TYPE_MIN_VALUE (TREE_TYPE (TREE_OPERAND (val, 0)))); - - if (TREE_CODE (val) != INTEGER_CST) - return true; - - if (max) - return tree_int_cst_lt (val, min_or_max_val) == 0; - else - return tree_int_cst_lt (min_or_max_val, val) == 0; -} - -/* Return true if VAL (of type TYPE) can equal the minimum value of TYPE. - If REVERSE is true, minimum value is taken as maximum value. */ - -static inline bool -can_equal_min_val_p (tree val, tree type, bool reverse) -{ - return can_equal_min_or_max_val_p (val, type, reverse); -} - -/* Return true if VAL (of type TYPE) can equal the maximum value of TYPE. - If REVERSE is true, maximum value is taken as minimum value. */ - -static inline bool -can_equal_max_val_p (tree val, tree type, bool reverse) -{ - return can_equal_min_or_max_val_p (val, type, !reverse); -} - -/* Replace EXPR1 and EXPR2 by invariant expressions if possible. Return - true if both expressions have been replaced and false otherwise. */ - -static bool -make_invariant (tree *expr1, tree *expr2) -{ - tree inv_expr1 = gnat_invariant_expr (*expr1); - tree inv_expr2 = gnat_invariant_expr (*expr2); - - if (inv_expr1) - *expr1 = inv_expr1; - - if (inv_expr2) - *expr2 = inv_expr2; - - return inv_expr1 && inv_expr2; -} - -/* Helper function for walk_tree, used by independent_iterations_p below. */ - -static tree -scan_rhs_r (tree *tp, int *walk_subtrees, void *data) -{ - bitmap *params = (bitmap *)data; - tree t = *tp; - - /* No need to walk into types or decls. */ - if (IS_TYPE_OR_DECL_P (t)) - *walk_subtrees = 0; - - if (TREE_CODE (t) == PARM_DECL && bitmap_bit_p (*params, DECL_UID (t))) - return t; - - return NULL_TREE; -} - -/* Return true if STMT_LIST generates independent iterations in a loop. */ - -static bool -independent_iterations_p (tree stmt_list) -{ - tree_stmt_iterator tsi; - bitmap params = BITMAP_GGC_ALLOC(); - auto_vec<tree, 16> rhs; - tree iter; - int i; - - if (TREE_CODE (stmt_list) == BIND_EXPR) - stmt_list = BIND_EXPR_BODY (stmt_list); - - /* Scan the list and return false on anything that is not either a check - or an assignment to a parameter with restricted aliasing. */ - for (tsi = tsi_start (stmt_list); !tsi_end_p (tsi); tsi_next (&tsi)) - { - tree stmt = tsi_stmt (tsi); - - switch (TREE_CODE (stmt)) - { - case COND_EXPR: - { - if (COND_EXPR_ELSE (stmt)) - return false; - if (TREE_CODE (COND_EXPR_THEN (stmt)) != CALL_EXPR) - return false; - tree func = get_callee_fndecl (COND_EXPR_THEN (stmt)); - if (!(func && TREE_THIS_VOLATILE (func))) - return false; - break; - } - - case MODIFY_EXPR: - { - tree lhs = TREE_OPERAND (stmt, 0); - while (handled_component_p (lhs)) - lhs = TREE_OPERAND (lhs, 0); - if (TREE_CODE (lhs) != INDIRECT_REF) - return false; - lhs = TREE_OPERAND (lhs, 0); - if (!(TREE_CODE (lhs) == PARM_DECL - && DECL_RESTRICTED_ALIASING_P (lhs))) - return false; - bitmap_set_bit (params, DECL_UID (lhs)); - rhs.safe_push (TREE_OPERAND (stmt, 1)); - break; - } - - default: - return false; - } - } - - /* At this point we know that the list contains only statements that will - modify parameters with restricted aliasing. Check that the statements - don't at the time read from these parameters. */ - FOR_EACH_VEC_ELT (rhs, i, iter) - if (walk_tree_without_duplicates (&iter, scan_rhs_r, ¶ms)) - return false; - - return true; -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, an N_Loop_Statement, - to a GCC tree, which is returned. */ - -static tree -Loop_Statement_to_gnu (Node_Id gnat_node) -{ - const Node_Id gnat_iter_scheme = Iteration_Scheme (gnat_node); - struct loop_info_d *gnu_loop_info = ggc_cleared_alloc<loop_info_d> (); - tree gnu_loop_stmt = build4 (LOOP_STMT, void_type_node, NULL_TREE, - NULL_TREE, NULL_TREE, NULL_TREE); - tree gnu_loop_label = create_artificial_label (input_location); - tree gnu_cond_expr = NULL_TREE, gnu_low = NULL_TREE, gnu_high = NULL_TREE; - tree gnu_result; - - /* Push the loop_info structure associated with the LOOP_STMT. */ - gnu_loop_info->fndecl = current_function_decl; - gnu_loop_info->stmt = gnu_loop_stmt; - vec_safe_push (gnu_loop_stack, gnu_loop_info); - - /* Set location information for statement and end label. */ - set_expr_location_from_node (gnu_loop_stmt, gnat_node); - Sloc_to_locus (Sloc (End_Label (gnat_node)), - &DECL_SOURCE_LOCATION (gnu_loop_label)); - LOOP_STMT_LABEL (gnu_loop_stmt) = gnu_loop_label; - - /* Set the condition under which the loop must keep going. If we have an - explicit condition, use it to set the location information throughout - the translation of the loop statement to avoid having multiple SLOCs. - - For the case "LOOP .... END LOOP;" the condition is always true. */ - if (No (gnat_iter_scheme)) - ; - - /* For the case "WHILE condition LOOP ..... END LOOP;" it's immediate. */ - else if (Present (Condition (gnat_iter_scheme))) - { - LOOP_STMT_COND (gnu_loop_stmt) - = gnat_to_gnu (Condition (gnat_iter_scheme)); - - set_expr_location_from_node (gnu_loop_stmt, gnat_iter_scheme); - } - - /* Otherwise we have an iteration scheme and the condition is given by the - bounds of the subtype of the iteration variable. */ - else - { - Node_Id gnat_loop_spec = Loop_Parameter_Specification (gnat_iter_scheme); - Entity_Id gnat_loop_var = Defining_Entity (gnat_loop_spec); - Entity_Id gnat_type = Etype (gnat_loop_var); - tree gnu_type = get_unpadded_type (gnat_type); - tree gnu_base_type = maybe_character_type (get_base_type (gnu_type)); - tree gnu_one_node = build_int_cst (gnu_base_type, 1); - tree gnu_loop_var, gnu_loop_iv, gnu_first, gnu_last, gnu_stmt; - enum tree_code update_code, test_code, shift_code; - bool reverse = Reverse_Present (gnat_loop_spec), use_iv = false; - - gnu_low = convert (gnu_base_type, TYPE_MIN_VALUE (gnu_type)); - gnu_high = convert (gnu_base_type, TYPE_MAX_VALUE (gnu_type)); - - /* We must disable modulo reduction for the iteration variable, if any, - in order for the loop comparison to be effective. */ - if (reverse) - { - gnu_first = gnu_high; - gnu_last = gnu_low; - update_code = MINUS_NOMOD_EXPR; - test_code = GE_EXPR; - shift_code = PLUS_NOMOD_EXPR; - } - else - { - gnu_first = gnu_low; - gnu_last = gnu_high; - update_code = PLUS_NOMOD_EXPR; - test_code = LE_EXPR; - shift_code = MINUS_NOMOD_EXPR; - } - - /* We use two different strategies to translate the loop, depending on - whether optimization is enabled. - - If it is, we generate the canonical loop form expected by the loop - optimizer and the loop vectorizer, which is the do-while form: - - ENTRY_COND - loop: - TOP_UPDATE - BODY - BOTTOM_COND - GOTO loop - - This avoids an implicit dependency on loop header copying and makes - it possible to turn BOTTOM_COND into an inequality test. - - If optimization is disabled, loop header copying doesn't come into - play and we try to generate the loop form with the fewer conditional - branches. First, the default form, which is: - - loop: - TOP_COND - BODY - BOTTOM_UPDATE - GOTO loop - - It should catch most loops with constant ending point. Then, if we - cannot, we try to generate the shifted form: - - loop: - TOP_COND - TOP_UPDATE - BODY - GOTO loop - - which should catch loops with constant starting point. Otherwise, if - we cannot, we generate the fallback form: - - ENTRY_COND - loop: - BODY - BOTTOM_COND - BOTTOM_UPDATE - GOTO loop - - which works in all cases. */ - - if (optimize && !optimize_debug) - { - /* We can use the do-while form directly if GNU_FIRST-1 doesn't - overflow. */ - if (!can_equal_min_val_p (gnu_first, gnu_base_type, reverse)) - ; - - /* Otherwise, use the do-while form with the help of a special - induction variable in the unsigned version of the base type - or the unsigned version of the size type, whichever is the - largest, in order to have wrap-around arithmetics for it. */ - else - { - if (TYPE_PRECISION (gnu_base_type) - > TYPE_PRECISION (size_type_node)) - gnu_base_type - = gnat_type_for_size (TYPE_PRECISION (gnu_base_type), 1); - else - gnu_base_type = size_type_node; - - gnu_first = convert (gnu_base_type, gnu_first); - gnu_last = convert (gnu_base_type, gnu_last); - gnu_one_node = build_int_cst (gnu_base_type, 1); - use_iv = true; - } - - gnu_first - = build_binary_op (shift_code, gnu_base_type, gnu_first, - gnu_one_node); - LOOP_STMT_TOP_UPDATE_P (gnu_loop_stmt) = 1; - LOOP_STMT_BOTTOM_COND_P (gnu_loop_stmt) = 1; - } - else - { - /* We can use the default form if GNU_LAST+1 doesn't overflow. */ - if (!can_equal_max_val_p (gnu_last, gnu_base_type, reverse)) - ; - - /* Otherwise, we can use the shifted form if neither GNU_FIRST-1 nor - GNU_LAST-1 does. */ - else if (!can_equal_min_val_p (gnu_first, gnu_base_type, reverse) - && !can_equal_min_val_p (gnu_last, gnu_base_type, reverse)) - { - gnu_first - = build_binary_op (shift_code, gnu_base_type, gnu_first, - gnu_one_node); - gnu_last - = build_binary_op (shift_code, gnu_base_type, gnu_last, - gnu_one_node); - LOOP_STMT_TOP_UPDATE_P (gnu_loop_stmt) = 1; - } - - /* Otherwise, use the fallback form. */ - else - LOOP_STMT_BOTTOM_COND_P (gnu_loop_stmt) = 1; - } - - /* If we use the BOTTOM_COND, we can turn the test into an inequality - test but we have to add ENTRY_COND to protect the empty loop. */ - if (LOOP_STMT_BOTTOM_COND_P (gnu_loop_stmt)) - { - test_code = NE_EXPR; - gnu_cond_expr - = build3 (COND_EXPR, void_type_node, - build_binary_op (LE_EXPR, boolean_type_node, - gnu_low, gnu_high), - NULL_TREE, alloc_stmt_list ()); - set_expr_location_from_node (gnu_cond_expr, gnat_iter_scheme); - } - - /* Open a new nesting level that will surround the loop to declare the - iteration variable. */ - start_stmt_group (); - gnat_pushlevel (); - - /* If we use the special induction variable, create it and set it to - its initial value. Morever, the regular iteration variable cannot - itself be initialized, lest the initial value wrapped around. */ - if (use_iv) - { - gnu_loop_iv - = create_init_temporary ("I", gnu_first, &gnu_stmt, gnat_loop_var); - add_stmt (gnu_stmt); - gnu_first = NULL_TREE; - } - else - gnu_loop_iv = NULL_TREE; - - /* Declare the iteration variable and set it to its initial value. */ - gnu_loop_var = gnat_to_gnu_entity (gnat_loop_var, gnu_first, true); - if (DECL_BY_REF_P (gnu_loop_var)) - gnu_loop_var = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_loop_var); - else if (use_iv) - { - gcc_assert (DECL_LOOP_PARM_P (gnu_loop_var)); - SET_DECL_INDUCTION_VAR (gnu_loop_var, gnu_loop_iv); - } - gnu_loop_info->loop_var = gnu_loop_var; - gnu_loop_info->low_bound = gnu_low; - gnu_loop_info->high_bound = gnu_high; - - /* Do all the arithmetics in the base type. */ - gnu_loop_var = convert (gnu_base_type, gnu_loop_var); - - /* Set either the top or bottom exit condition. */ - if (use_iv) - LOOP_STMT_COND (gnu_loop_stmt) - = build_binary_op (test_code, boolean_type_node, gnu_loop_iv, - gnu_last); - else - LOOP_STMT_COND (gnu_loop_stmt) - = build_binary_op (test_code, boolean_type_node, gnu_loop_var, - gnu_last); - - /* Set either the top or bottom update statement and give it the source - location of the iteration for better coverage info. */ - if (use_iv) - { - gnu_stmt - = build_binary_op (MODIFY_EXPR, NULL_TREE, gnu_loop_iv, - build_binary_op (update_code, gnu_base_type, - gnu_loop_iv, gnu_one_node)); - set_expr_location_from_node (gnu_stmt, gnat_iter_scheme); - append_to_statement_list (gnu_stmt, - &LOOP_STMT_UPDATE (gnu_loop_stmt)); - gnu_stmt - = build_binary_op (MODIFY_EXPR, NULL_TREE, gnu_loop_var, - gnu_loop_iv); - set_expr_location_from_node (gnu_stmt, gnat_iter_scheme); - append_to_statement_list (gnu_stmt, - &LOOP_STMT_UPDATE (gnu_loop_stmt)); - } - else - { - gnu_stmt - = build_binary_op (MODIFY_EXPR, NULL_TREE, gnu_loop_var, - build_binary_op (update_code, gnu_base_type, - gnu_loop_var, gnu_one_node)); - set_expr_location_from_node (gnu_stmt, gnat_iter_scheme); - LOOP_STMT_UPDATE (gnu_loop_stmt) = gnu_stmt; - } - - set_expr_location_from_node (gnu_loop_stmt, gnat_iter_scheme); - } - - /* If the loop was named, have the name point to this loop. In this case, - the association is not a DECL node, but the end label of the loop. */ - if (Present (Identifier (gnat_node))) - save_gnu_tree (Entity (Identifier (gnat_node)), gnu_loop_label, true); - - /* Make the loop body into its own block, so any allocated storage will be - released every iteration. This is needed for stack allocation. */ - LOOP_STMT_BODY (gnu_loop_stmt) - = build_stmt_group (Statements (gnat_node), true); - TREE_SIDE_EFFECTS (gnu_loop_stmt) = 1; - - /* If we have an iteration scheme, then we are in a statement group. Add - the LOOP_STMT to it, finish it and make it the "loop". */ - if (Present (gnat_iter_scheme) && No (Condition (gnat_iter_scheme))) - { - /* First, if we have computed invariant conditions for range (or index) - checks applied to the iteration variable, find out whether they can - be evaluated to false at compile time; otherwise, if there are not - too many of them, combine them with the original checks. If loop - unswitching is enabled, do not require the loop bounds to be also - invariant, as their evaluation will still be ahead of the loop. */ - if (vec_safe_length (gnu_loop_info->checks) > 0 - && (make_invariant (&gnu_low, &gnu_high) || optimize >= 3)) - { - struct range_check_info_d *rci; - unsigned int i, n_remaining_checks = 0; - - FOR_EACH_VEC_ELT (*gnu_loop_info->checks, i, rci) - { - tree low_ok, high_ok; - - if (rci->low_bound) - { - tree gnu_adjusted_low = convert (rci->type, gnu_low); - if (rci->disp) - gnu_adjusted_low - = fold_build2 (rci->neg_p ? MINUS_EXPR : PLUS_EXPR, - rci->type, gnu_adjusted_low, rci->disp); - low_ok - = build_binary_op (GE_EXPR, boolean_type_node, - gnu_adjusted_low, rci->low_bound); - } - else - low_ok = boolean_true_node; - - if (rci->high_bound) - { - tree gnu_adjusted_high = convert (rci->type, gnu_high); - if (rci->disp) - gnu_adjusted_high - = fold_build2 (rci->neg_p ? MINUS_EXPR : PLUS_EXPR, - rci->type, gnu_adjusted_high, rci->disp); - high_ok - = build_binary_op (LE_EXPR, boolean_type_node, - gnu_adjusted_high, rci->high_bound); - } - else - high_ok = boolean_true_node; - - tree range_ok - = build_binary_op (TRUTH_ANDIF_EXPR, boolean_type_node, - low_ok, high_ok); - - rci->invariant_cond - = build_unary_op (TRUTH_NOT_EXPR, boolean_type_node, range_ok); - - if (rci->invariant_cond == boolean_false_node) - TREE_OPERAND (rci->inserted_cond, 0) = rci->invariant_cond; - else - n_remaining_checks++; - } - - /* Note that loop unswitching can only be applied a small number of - times to a given loop (PARAM_MAX_UNSWITCH_LEVEL default to 3). */ - if (IN_RANGE (n_remaining_checks, 1, 3) - && optimize >= 2 - && !optimize_size) - FOR_EACH_VEC_ELT (*gnu_loop_info->checks, i, rci) - if (rci->invariant_cond != boolean_false_node) - { - TREE_OPERAND (rci->inserted_cond, 0) = rci->invariant_cond; - - if (optimize >= 3) - add_stmt_with_node_force (rci->inserted_cond, gnat_node); - } - } - - /* Second, if we have recorded invariants to be hoisted, emit them. */ - if (vec_safe_length (gnu_loop_info->invariants) > 0) - { - tree *iter; - unsigned int i; - FOR_EACH_VEC_ELT (*gnu_loop_info->invariants, i, iter) - add_stmt_with_node_force (*iter, gnat_node); - } - - /* Third, if loop vectorization is enabled and the iterations of the - loop can easily be proved as independent, mark the loop. */ - if (optimize >= 3 - && independent_iterations_p (LOOP_STMT_BODY (gnu_loop_stmt))) - LOOP_STMT_IVDEP (gnu_loop_stmt) = 1; - - add_stmt (gnu_loop_stmt); - gnat_poplevel (); - gnu_loop_stmt = end_stmt_group (); - } - - /* If we have an outer COND_EXPR, that's our result and this loop is its - "true" statement. Otherwise, the result is the LOOP_STMT. */ - if (gnu_cond_expr) - { - COND_EXPR_THEN (gnu_cond_expr) = gnu_loop_stmt; - TREE_SIDE_EFFECTS (gnu_cond_expr) = 1; - gnu_result = gnu_cond_expr; - } - else - gnu_result = gnu_loop_stmt; - - gnu_loop_stack->pop (); - - return gnu_result; -} - -/* This page implements a form of Named Return Value optimization modeled - on the C++ optimization of the same name. The main difference is that - we disregard any semantical considerations when applying it here, the - counterpart being that we don't try to apply it to semantically loaded - return types, i.e. types with the TYPE_BY_REFERENCE_P flag set. - - We consider a function body of the following GENERIC form: - - return_type R1; - [...] - RETURN_EXPR [<retval> = ...] - [...] - RETURN_EXPR [<retval> = R1] - [...] - return_type Ri; - [...] - RETURN_EXPR [<retval> = ...] - [...] - RETURN_EXPR [<retval> = Ri] - [...] - - where the Ri are not addressable and we try to fulfill a simple criterion - that would make it possible to replace one or several Ri variables by the - single RESULT_DECL of the function. - - The first observation is that RETURN_EXPRs that don't directly reference - any of the Ri variables on the RHS of their assignment are transparent wrt - the optimization. This is because the Ri variables aren't addressable so - any transformation applied to them doesn't affect the RHS; moreover, the - assignment writes the full <retval> object so existing values are entirely - discarded. - - This property can be extended to some forms of RETURN_EXPRs that reference - the Ri variables, for example CONSTRUCTORs, but isn't true in the general - case, in particular when function calls are involved. - - Therefore the algorithm is as follows: - - 1. Collect the list of candidates for a Named Return Value (Ri variables - on the RHS of assignments of RETURN_EXPRs) as well as the list of the - other expressions on the RHS of such assignments. - - 2. Prune the members of the first list (candidates) that are referenced - by a member of the second list (expressions). - - 3. Extract a set of candidates with non-overlapping live ranges from the - first list. These are the Named Return Values. - - 4. Adjust the relevant RETURN_EXPRs and replace the occurrences of the - Named Return Values in the function with the RESULT_DECL. - - If the function returns an unconstrained type, things are a bit different - because the anonymous return object is allocated on the secondary stack - and RESULT_DECL is only a pointer to it. Each return object can be of a - different size and is allocated separately so we need not care about the - addressability and the aforementioned overlapping issues. Therefore, we - don't collect the other expressions and skip step #2 in the algorithm. */ - -struct nrv_data -{ - bitmap nrv; - tree result; - Node_Id gnat_ret; - hash_set<tree> *visited; -}; - -/* Return true if T is a Named Return Value. */ - -static inline bool -is_nrv_p (bitmap nrv, tree t) -{ - return TREE_CODE (t) == VAR_DECL && bitmap_bit_p (nrv, DECL_UID (t)); -} - -/* Helper function for walk_tree, used by finalize_nrv below. */ - -static tree -prune_nrv_r (tree *tp, int *walk_subtrees, void *data) -{ - struct nrv_data *dp = (struct nrv_data *)data; - tree t = *tp; - - /* No need to walk into types or decls. */ - if (IS_TYPE_OR_DECL_P (t)) - *walk_subtrees = 0; - - if (is_nrv_p (dp->nrv, t)) - bitmap_clear_bit (dp->nrv, DECL_UID (t)); - - return NULL_TREE; -} - -/* Prune Named Return Values in BLOCK and return true if there is still a - Named Return Value in BLOCK or one of its sub-blocks. */ - -static bool -prune_nrv_in_block (bitmap nrv, tree block) -{ - bool has_nrv = false; - tree t; - - /* First recurse on the sub-blocks. */ - for (t = BLOCK_SUBBLOCKS (block); t; t = BLOCK_CHAIN (t)) - has_nrv |= prune_nrv_in_block (nrv, t); - - /* Then make sure to keep at most one NRV per block. */ - for (t = BLOCK_VARS (block); t; t = DECL_CHAIN (t)) - if (is_nrv_p (nrv, t)) - { - if (has_nrv) - bitmap_clear_bit (nrv, DECL_UID (t)); - else - has_nrv = true; - } - - return has_nrv; -} - -/* Helper function for walk_tree, used by finalize_nrv below. */ - -static tree -finalize_nrv_r (tree *tp, int *walk_subtrees, void *data) -{ - struct nrv_data *dp = (struct nrv_data *)data; - tree t = *tp; - - /* No need to walk into types. */ - if (TYPE_P (t)) - *walk_subtrees = 0; - - /* Change RETURN_EXPRs of NRVs to just refer to the RESULT_DECL; this is a - nop, but differs from using NULL_TREE in that it indicates that we care - about the value of the RESULT_DECL. */ - else if (TREE_CODE (t) == RETURN_EXPR - && TREE_CODE (TREE_OPERAND (t, 0)) == INIT_EXPR) - { - tree ret_val = TREE_OPERAND (TREE_OPERAND (t, 0), 1); - - /* Strip useless conversions around the return value. */ - if (gnat_useless_type_conversion (ret_val)) - ret_val = TREE_OPERAND (ret_val, 0); - - if (is_nrv_p (dp->nrv, ret_val)) - TREE_OPERAND (t, 0) = dp->result; - } - - /* Replace the DECL_EXPR of NRVs with an initialization of the RESULT_DECL, - if needed. */ - else if (TREE_CODE (t) == DECL_EXPR - && is_nrv_p (dp->nrv, DECL_EXPR_DECL (t))) - { - tree var = DECL_EXPR_DECL (t), init; - - if (DECL_INITIAL (var)) - { - init = build_binary_op (INIT_EXPR, NULL_TREE, dp->result, - DECL_INITIAL (var)); - SET_EXPR_LOCATION (init, EXPR_LOCATION (t)); - DECL_INITIAL (var) = NULL_TREE; - } - else - init = build_empty_stmt (EXPR_LOCATION (t)); - *tp = init; - - /* Identify the NRV to the RESULT_DECL for debugging purposes. */ - SET_DECL_VALUE_EXPR (var, dp->result); - DECL_HAS_VALUE_EXPR_P (var) = 1; - /* ??? Kludge to avoid an assertion failure during inlining. */ - DECL_SIZE (var) = bitsize_unit_node; - DECL_SIZE_UNIT (var) = size_one_node; - } - - /* And replace all uses of NRVs with the RESULT_DECL. */ - else if (is_nrv_p (dp->nrv, t)) - *tp = convert (TREE_TYPE (t), dp->result); - - /* Avoid walking into the same tree more than once. Unfortunately, we - can't just use walk_tree_without_duplicates because it would only - call us for the first occurrence of NRVs in the function body. */ - if (dp->visited->add (*tp)) - *walk_subtrees = 0; - - return NULL_TREE; -} - -/* Likewise, but used when the function returns an unconstrained type. */ - -static tree -finalize_nrv_unc_r (tree *tp, int *walk_subtrees, void *data) -{ - struct nrv_data *dp = (struct nrv_data *)data; - tree t = *tp; - - /* No need to walk into types. */ - if (TYPE_P (t)) - *walk_subtrees = 0; - - /* We need to see the DECL_EXPR of NRVs before any other references so we - walk the body of BIND_EXPR before walking its variables. */ - else if (TREE_CODE (t) == BIND_EXPR) - walk_tree (&BIND_EXPR_BODY (t), finalize_nrv_unc_r, data, NULL); - - /* Change RETURN_EXPRs of NRVs to assign to the RESULT_DECL only the final - return value built by the allocator instead of the whole construct. */ - else if (TREE_CODE (t) == RETURN_EXPR - && TREE_CODE (TREE_OPERAND (t, 0)) == INIT_EXPR) - { - tree ret_val = TREE_OPERAND (TREE_OPERAND (t, 0), 1); - - /* This is the construct returned by the allocator. */ - if (TREE_CODE (ret_val) == COMPOUND_EXPR - && TREE_CODE (TREE_OPERAND (ret_val, 0)) == INIT_EXPR) - { - tree rhs = TREE_OPERAND (TREE_OPERAND (ret_val, 0), 1); - - if (TYPE_IS_FAT_POINTER_P (TREE_TYPE (ret_val))) - ret_val = CONSTRUCTOR_ELT (rhs, 1)->value; - else - ret_val = rhs; - } - - /* Strip useless conversions around the return value. */ - if (gnat_useless_type_conversion (ret_val) - || TREE_CODE (ret_val) == VIEW_CONVERT_EXPR) - ret_val = TREE_OPERAND (ret_val, 0); - - /* Strip unpadding around the return value. */ - if (TREE_CODE (ret_val) == COMPONENT_REF - && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (ret_val, 0)))) - ret_val = TREE_OPERAND (ret_val, 0); - - /* Assign the new return value to the RESULT_DECL. */ - if (is_nrv_p (dp->nrv, ret_val)) - TREE_OPERAND (TREE_OPERAND (t, 0), 1) - = TREE_OPERAND (DECL_INITIAL (ret_val), 0); - } - - /* Adjust the DECL_EXPR of NRVs to call the allocator and save the result - into a new variable. */ - else if (TREE_CODE (t) == DECL_EXPR - && is_nrv_p (dp->nrv, DECL_EXPR_DECL (t))) - { - tree saved_current_function_decl = current_function_decl; - tree var = DECL_EXPR_DECL (t); - tree alloc, p_array, new_var, new_ret; - vec<constructor_elt, va_gc> *v; - vec_alloc (v, 2); - - /* Create an artificial context to build the allocation. */ - current_function_decl = decl_function_context (var); - start_stmt_group (); - gnat_pushlevel (); - - /* This will return a COMPOUND_EXPR with the allocation in the first - arm and the final return value in the second arm. */ - alloc = build_allocator (TREE_TYPE (var), DECL_INITIAL (var), - TREE_TYPE (dp->result), - Procedure_To_Call (dp->gnat_ret), - Storage_Pool (dp->gnat_ret), - Empty, false); - - /* The new variable is built as a reference to the allocated space. */ - new_var - = build_decl (DECL_SOURCE_LOCATION (var), VAR_DECL, DECL_NAME (var), - build_reference_type (TREE_TYPE (var))); - DECL_BY_REFERENCE (new_var) = 1; - - if (TYPE_IS_FAT_POINTER_P (TREE_TYPE (alloc))) - { - tree cst = TREE_OPERAND (alloc, 1); - - /* The new initial value is a COMPOUND_EXPR with the allocation in - the first arm and the value of P_ARRAY in the second arm. */ - DECL_INITIAL (new_var) - = build2 (COMPOUND_EXPR, TREE_TYPE (new_var), - TREE_OPERAND (alloc, 0), - CONSTRUCTOR_ELT (cst, 0)->value); - - /* Build a modified CONSTRUCTOR that references NEW_VAR. */ - p_array = TYPE_FIELDS (TREE_TYPE (alloc)); - CONSTRUCTOR_APPEND_ELT (v, p_array, - fold_convert (TREE_TYPE (p_array), new_var)); - CONSTRUCTOR_APPEND_ELT (v, DECL_CHAIN (p_array), - CONSTRUCTOR_ELT (cst, 1)->value); - new_ret = build_constructor (TREE_TYPE (alloc), v); - } - else - { - /* The new initial value is just the allocation. */ - DECL_INITIAL (new_var) = alloc; - new_ret = fold_convert (TREE_TYPE (alloc), new_var); - } - - gnat_pushdecl (new_var, Empty); - - /* Destroy the artificial context and insert the new statements. */ - gnat_zaplevel (); - *tp = end_stmt_group (); - current_function_decl = saved_current_function_decl; - - /* Chain NEW_VAR immediately after VAR and ignore the latter. */ - DECL_CHAIN (new_var) = DECL_CHAIN (var); - DECL_CHAIN (var) = new_var; - DECL_IGNORED_P (var) = 1; - - /* Save the new return value and the dereference of NEW_VAR. */ - DECL_INITIAL (var) - = build2 (COMPOUND_EXPR, TREE_TYPE (var), new_ret, - build1 (INDIRECT_REF, TREE_TYPE (var), new_var)); - /* ??? Kludge to avoid messing up during inlining. */ - DECL_CONTEXT (var) = NULL_TREE; - } - - /* And replace all uses of NRVs with the dereference of NEW_VAR. */ - else if (is_nrv_p (dp->nrv, t)) - *tp = TREE_OPERAND (DECL_INITIAL (t), 1); - - /* Avoid walking into the same tree more than once. Unfortunately, we - can't just use walk_tree_without_duplicates because it would only - call us for the first occurrence of NRVs in the function body. */ - if (dp->visited->add (*tp)) - *walk_subtrees = 0; - - return NULL_TREE; -} - -/* Apply FUNC to all the sub-trees of nested functions in NODE. FUNC is called - with the DATA and the address of each sub-tree. If FUNC returns a non-NULL - value, the traversal is stopped. */ - -static void -walk_nesting_tree (struct cgraph_node *node, walk_tree_fn func, void *data) -{ - for (node = first_nested_function (node); - node; node = next_nested_function (node)) - { - walk_tree_without_duplicates (&DECL_SAVED_TREE (node->decl), func, data); - walk_nesting_tree (node, func, data); - } -} - -/* Finalize the Named Return Value optimization for FNDECL. The NRV bitmap - contains the candidates for Named Return Value and OTHER is a list of - the other return values. GNAT_RET is a representative return node. */ - -static void -finalize_nrv (tree fndecl, bitmap nrv, vec<tree, va_gc> *other, Node_Id gnat_ret) -{ - struct nrv_data data; - walk_tree_fn func; - unsigned int i; - tree iter; - - /* We shouldn't be applying the optimization to return types that we aren't - allowed to manipulate freely. */ - gcc_assert (!TYPE_IS_BY_REFERENCE_P (TREE_TYPE (TREE_TYPE (fndecl)))); - - /* Prune the candidates that are referenced by other return values. */ - data.nrv = nrv; - data.result = NULL_TREE; - data.gnat_ret = Empty; - data.visited = NULL; - FOR_EACH_VEC_SAFE_ELT (other, i, iter) - walk_tree_without_duplicates (&iter, prune_nrv_r, &data); - if (bitmap_empty_p (nrv)) - return; - - /* Prune also the candidates that are referenced by nested functions. */ - walk_nesting_tree (cgraph_node::get_create (fndecl), prune_nrv_r, &data); - if (bitmap_empty_p (nrv)) - return; - - /* Extract a set of NRVs with non-overlapping live ranges. */ - if (!prune_nrv_in_block (nrv, DECL_INITIAL (fndecl))) - return; - - /* Adjust the relevant RETURN_EXPRs and replace the occurrences of NRVs. */ - data.nrv = nrv; - data.result = DECL_RESULT (fndecl); - data.gnat_ret = gnat_ret; - data.visited = new hash_set<tree>; - if (TYPE_RETURN_UNCONSTRAINED_P (TREE_TYPE (fndecl))) - func = finalize_nrv_unc_r; - else - func = finalize_nrv_r; - walk_tree (&DECL_SAVED_TREE (fndecl), func, &data, NULL); - delete data.visited; -} - -/* Return true if RET_VAL can be used as a Named Return Value for the - anonymous return object RET_OBJ. */ - -static bool -return_value_ok_for_nrv_p (tree ret_obj, tree ret_val) -{ - if (TREE_CODE (ret_val) != VAR_DECL) - return false; - - if (TREE_THIS_VOLATILE (ret_val)) - return false; - - if (DECL_CONTEXT (ret_val) != current_function_decl) - return false; - - if (TREE_STATIC (ret_val)) - return false; - - /* For the constrained case, test for addressability. */ - if (ret_obj && TREE_ADDRESSABLE (ret_val)) - return false; - - /* For the constrained case, test for overalignment. */ - if (ret_obj && DECL_ALIGN (ret_val) > DECL_ALIGN (ret_obj)) - return false; - - /* For the unconstrained case, test for bogus initialization. */ - if (!ret_obj - && DECL_INITIAL (ret_val) - && TREE_CODE (DECL_INITIAL (ret_val)) == NULL_EXPR) - return false; - - return true; -} - -/* Build a RETURN_EXPR. If RET_VAL is non-null, build a RETURN_EXPR around - the assignment of RET_VAL to RET_OBJ. Otherwise build a bare RETURN_EXPR - around RESULT_OBJ, which may be null in this case. */ - -static tree -build_return_expr (tree ret_obj, tree ret_val) -{ - tree result_expr; - - if (ret_val) - { - /* The gimplifier explicitly enforces the following invariant: - - RETURN_EXPR - | - INIT_EXPR - / \ - / \ - RET_OBJ ... - - As a consequence, type consistency dictates that we use the type - of the RET_OBJ as the operation type. */ - tree operation_type = TREE_TYPE (ret_obj); - - /* Convert the right operand to the operation type. Note that this is - the transformation applied in the INIT_EXPR case of build_binary_op, - with the assumption that the type cannot involve a placeholder. */ - if (operation_type != TREE_TYPE (ret_val)) - ret_val = convert (operation_type, ret_val); - - /* We always can use an INIT_EXPR for the return object. */ - result_expr = build2 (INIT_EXPR, void_type_node, ret_obj, ret_val); - - /* If the function returns an aggregate type, find out whether this is - a candidate for Named Return Value. If so, record it. Otherwise, - if this is an expression of some kind, record it elsewhere. */ - if (optimize - && !optimize_debug - && AGGREGATE_TYPE_P (operation_type) - && !TYPE_IS_FAT_POINTER_P (operation_type) - && TYPE_MODE (operation_type) == BLKmode - && aggregate_value_p (operation_type, current_function_decl)) - { - /* Strip useless conversions around the return value. */ - if (gnat_useless_type_conversion (ret_val)) - ret_val = TREE_OPERAND (ret_val, 0); - - /* Now apply the test to the return value. */ - if (return_value_ok_for_nrv_p (ret_obj, ret_val)) - { - if (!f_named_ret_val) - f_named_ret_val = BITMAP_GGC_ALLOC (); - bitmap_set_bit (f_named_ret_val, DECL_UID (ret_val)); - } - - /* Note that we need not care about CONSTRUCTORs here, as they are - totally transparent given the read-compose-write semantics of - assignments from CONSTRUCTORs. */ - else if (EXPR_P (ret_val)) - vec_safe_push (f_other_ret_val, ret_val); - } - } - else - result_expr = ret_obj; - - return build1 (RETURN_EXPR, void_type_node, result_expr); -} - -/* Subroutine of gnat_to_gnu to process gnat_node, an N_Subprogram_Body. We - don't return anything. */ - -static void -Subprogram_Body_to_gnu (Node_Id gnat_node) -{ - /* Defining identifier of a parameter to the subprogram. */ - Entity_Id gnat_param; - /* The defining identifier for the subprogram body. Note that if a - specification has appeared before for this body, then the identifier - occurring in that specification will also be a defining identifier and all - the calls to this subprogram will point to that specification. */ - Entity_Id gnat_subprog_id - = (Present (Corresponding_Spec (gnat_node)) - ? Corresponding_Spec (gnat_node) : Defining_Entity (gnat_node)); - /* The FUNCTION_DECL node corresponding to the subprogram spec. */ - tree gnu_subprog_decl; - /* Its RESULT_DECL node. */ - tree gnu_result_decl; - /* Its FUNCTION_TYPE node. */ - tree gnu_subprog_type; - /* The TYPE_CI_CO_LIST of its FUNCTION_TYPE node, if any. */ - tree gnu_cico_list; - /* The entry in the CI_CO_LIST that represents a function return, if any. */ - tree gnu_return_var_elmt = NULL_TREE; - tree gnu_result; - location_t locus; - struct language_function *gnu_subprog_language; - vec<parm_attr, va_gc> *cache; - - /* If this is a generic object or if it has been eliminated, - ignore it. */ - if (Ekind (gnat_subprog_id) == E_Generic_Procedure - || Ekind (gnat_subprog_id) == E_Generic_Function - || Is_Eliminated (gnat_subprog_id)) - return; - - /* If this subprogram acts as its own spec, define it. Otherwise, just get - the already-elaborated tree node. However, if this subprogram had its - elaboration deferred, we will already have made a tree node for it. So - treat it as not being defined in that case. Such a subprogram cannot - have an address clause or a freeze node, so this test is safe, though it - does disable some otherwise-useful error checking. */ - gnu_subprog_decl - = gnat_to_gnu_entity (gnat_subprog_id, NULL_TREE, - Acts_As_Spec (gnat_node) - && !present_gnu_tree (gnat_subprog_id)); - DECL_FUNCTION_IS_DEF (gnu_subprog_decl) = true; - gnu_result_decl = DECL_RESULT (gnu_subprog_decl); - gnu_subprog_type = TREE_TYPE (gnu_subprog_decl); - gnu_cico_list = TYPE_CI_CO_LIST (gnu_subprog_type); - if (gnu_cico_list && TREE_VALUE (gnu_cico_list) == void_type_node) - gnu_return_var_elmt = gnu_cico_list; - - /* If the function returns by invisible reference, make it explicit in the - function body. See gnat_to_gnu_entity, E_Subprogram_Type case. */ - if (TREE_ADDRESSABLE (gnu_subprog_type)) - { - TREE_TYPE (gnu_result_decl) - = build_reference_type (TREE_TYPE (gnu_result_decl)); - relayout_decl (gnu_result_decl); - } - - /* Set the line number in the decl to correspond to that of the body. */ - if (DECL_IGNORED_P (gnu_subprog_decl)) - locus = UNKNOWN_LOCATION; - else if (!Sloc_to_locus (Sloc (gnat_node), &locus, false, gnu_subprog_decl)) - locus = input_location; - DECL_SOURCE_LOCATION (gnu_subprog_decl) = locus; - - /* If the body comes from an expression function, arrange it to be inlined - in almost all cases. */ - if (Was_Expression_Function (gnat_node) && !Debug_Flag_Dot_8) - DECL_DISREGARD_INLINE_LIMITS (gnu_subprog_decl) = 1; - - /* Try to create a bona-fide thunk and hand it over to the middle-end. */ - if (Is_Thunk (gnat_subprog_id) - && maybe_make_gnu_thunk (gnat_subprog_id, gnu_subprog_decl)) - return; - - /* Initialize the information structure for the function. */ - allocate_struct_function (gnu_subprog_decl, false); - gnu_subprog_language = ggc_cleared_alloc<language_function> (); - DECL_STRUCT_FUNCTION (gnu_subprog_decl)->language = gnu_subprog_language; - DECL_STRUCT_FUNCTION (gnu_subprog_decl)->function_start_locus = locus; - set_cfun (NULL); - - begin_subprog_body (gnu_subprog_decl); - - /* If there are copy-in/copy-out parameters, we need to ensure that they are - properly copied out by the return statement. We do this by making a new - block and converting any return into a goto to a label at the end of the - block. */ - if (gnu_cico_list) - { - tree gnu_return_var = NULL_TREE; - - vec_safe_push (gnu_return_label_stack, - create_artificial_label (input_location)); - - start_stmt_group (); - gnat_pushlevel (); - - /* If this is a function with copy-in/copy-out parameters and which does - not return by invisible reference, we also need a variable for the - return value to be placed. */ - if (gnu_return_var_elmt && !TREE_ADDRESSABLE (gnu_subprog_type)) - { - tree gnu_return_type - = TREE_TYPE (TREE_PURPOSE (gnu_return_var_elmt)); - - gnu_return_var - = create_var_decl (get_identifier ("RETVAL"), NULL_TREE, - gnu_return_type, NULL_TREE, - false, false, false, false, false, - true, false, NULL, gnat_subprog_id); - TREE_VALUE (gnu_return_var_elmt) = gnu_return_var; - } - - vec_safe_push (gnu_return_var_stack, gnu_return_var); - - /* See whether there are parameters for which we don't have a GCC tree - yet. These must be Out parameters. Make a VAR_DECL for them and - put it into TYPE_CI_CO_LIST, which must contain an empty entry too. - We can match up the entries because TYPE_CI_CO_LIST is in the order - of the parameters. */ - for (gnat_param = First_Formal_With_Extras (gnat_subprog_id); - Present (gnat_param); - gnat_param = Next_Formal_With_Extras (gnat_param)) - if (!present_gnu_tree (gnat_param)) - { - tree gnu_cico_entry = gnu_cico_list; - tree gnu_decl; - - /* Skip any entries that have been already filled in; they must - correspond to In Out parameters. */ - while (gnu_cico_entry && TREE_VALUE (gnu_cico_entry)) - gnu_cico_entry = TREE_CHAIN (gnu_cico_entry); - - /* Do any needed dereferences for by-ref objects. */ - gnu_decl = gnat_to_gnu_entity (gnat_param, NULL_TREE, true); - gcc_assert (DECL_P (gnu_decl)); - if (DECL_BY_REF_P (gnu_decl)) - gnu_decl = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_decl); - - /* Do any needed references for padded types. */ - TREE_VALUE (gnu_cico_entry) - = convert (TREE_TYPE (TREE_PURPOSE (gnu_cico_entry)), gnu_decl); - } - } - else - vec_safe_push (gnu_return_label_stack, NULL_TREE); - - /* Get a tree corresponding to the code for the subprogram. */ - start_stmt_group (); - gnat_pushlevel (); - - process_decls (Declarations (gnat_node), Empty, Empty, true, true); - - /* Generate the code of the subprogram itself. A return statement will be - present and any Out parameters will be handled there. */ - add_stmt (gnat_to_gnu (Handled_Statement_Sequence (gnat_node))); - gnat_poplevel (); - gnu_result = end_stmt_group (); - - /* Attempt setting the end_locus of our GCC body tree, typically a BIND_EXPR, - then the end_locus of our GCC subprogram declaration tree. */ - set_end_locus_from_node (gnu_result, gnat_node); - set_end_locus_from_node (gnu_subprog_decl, gnat_node); - - /* If we populated the parameter attributes cache, we need to make sure that - the cached expressions are evaluated on all the possible paths leading to - their uses. So we force their evaluation on entry of the function. */ - cache = gnu_subprog_language->parm_attr_cache; - if (cache) - { - struct parm_attr_d *pa; - int i; - - start_stmt_group (); - - FOR_EACH_VEC_ELT (*cache, i, pa) - { - if (pa->first) - add_stmt_with_node_force (pa->first, gnat_node); - if (pa->last) - add_stmt_with_node_force (pa->last, gnat_node); - if (pa->length) - add_stmt_with_node_force (pa->length, gnat_node); - } - - add_stmt (gnu_result); - gnu_result = end_stmt_group (); - - gnu_subprog_language->parm_attr_cache = NULL; - } - - /* If we are dealing with a return from an Ada procedure with parameters - passed by copy-in/copy-out, we need to return a record containing the - final values of these parameters. If the list contains only one entry, - return just that entry though. - - For a full description of the copy-in/copy-out parameter mechanism, see - the part of the gnat_to_gnu_entity routine dealing with the translation - of subprograms. - - We need to make a block that contains the definition of that label and - the copying of the return value. It first contains the function, then - the label and copy statement. */ - if (gnu_cico_list) - { - const Node_Id gnat_end_label - = End_Label (Handled_Statement_Sequence (gnat_node)); - - gnu_return_var_stack->pop (); - - add_stmt (gnu_result); - add_stmt (build1 (LABEL_EXPR, void_type_node, - gnu_return_label_stack->last ())); - - /* If this is a function which returns by invisible reference, the - return value has already been dealt with at the return statements, - so we only need to indirectly copy out the parameters. */ - if (TREE_ADDRESSABLE (gnu_subprog_type)) - { - tree gnu_ret_deref - = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_result_decl); - tree t; - - gcc_assert (TREE_VALUE (gnu_cico_list) == void_type_node); - - for (t = TREE_CHAIN (gnu_cico_list); t; t = TREE_CHAIN (t)) - { - tree gnu_field_deref - = build_component_ref (gnu_ret_deref, TREE_PURPOSE (t), true); - gnu_result = build2 (MODIFY_EXPR, void_type_node, - gnu_field_deref, TREE_VALUE (t)); - add_stmt_with_node (gnu_result, gnat_end_label); - } - } - - /* Otherwise, if this is a procedure or a function which does not return - by invisible reference, we can do a direct block-copy out. */ - else - { - tree gnu_retval; - - if (list_length (gnu_cico_list) == 1) - gnu_retval = TREE_VALUE (gnu_cico_list); - else - gnu_retval - = build_constructor_from_list (TREE_TYPE (gnu_subprog_type), - gnu_cico_list); - - gnu_result = build_return_expr (gnu_result_decl, gnu_retval); - add_stmt_with_node (gnu_result, gnat_end_label); - } - - gnat_poplevel (); - gnu_result = end_stmt_group (); - } - - gnu_return_label_stack->pop (); - - /* On SEH targets, install an exception handler around the main entry - point to catch unhandled exceptions. */ - if (DECL_NAME (gnu_subprog_decl) == main_identifier_node - && targetm_common.except_unwind_info (&global_options) == UI_SEH) - { - tree t; - tree etype; - - t = build_call_expr (builtin_decl_explicit (BUILT_IN_EH_POINTER), - 1, integer_zero_node); - t = build_call_n_expr (unhandled_except_decl, 1, t); - - etype = build_unary_op (ADDR_EXPR, NULL_TREE, unhandled_others_decl); - etype = tree_cons (NULL_TREE, etype, NULL_TREE); - - t = build2 (CATCH_EXPR, void_type_node, etype, t); - gnu_result = build2 (TRY_CATCH_EXPR, TREE_TYPE (gnu_result), - gnu_result, t); - } - - end_subprog_body (gnu_result); - - /* Finally annotate the parameters and disconnect the trees for parameters - that we have turned into variables since they are now unusable. */ - for (gnat_param = First_Formal_With_Extras (gnat_subprog_id); - Present (gnat_param); - gnat_param = Next_Formal_With_Extras (gnat_param)) - { - tree gnu_param = get_gnu_tree (gnat_param); - bool is_var_decl = (TREE_CODE (gnu_param) == VAR_DECL); - - annotate_object (gnat_param, TREE_TYPE (gnu_param), NULL_TREE, - DECL_BY_REF_P (gnu_param)); - - if (is_var_decl) - save_gnu_tree (gnat_param, NULL_TREE, false); - } - - /* Disconnect the variable created for the return value. */ - if (gnu_return_var_elmt) - TREE_VALUE (gnu_return_var_elmt) = void_type_node; - - /* If the function returns an aggregate type and we have candidates for - a Named Return Value, finalize the optimization. */ - if (optimize && !optimize_debug && gnu_subprog_language->named_ret_val) - { - finalize_nrv (gnu_subprog_decl, - gnu_subprog_language->named_ret_val, - gnu_subprog_language->other_ret_val, - gnu_subprog_language->gnat_ret); - gnu_subprog_language->named_ret_val = NULL; - gnu_subprog_language->other_ret_val = NULL; - } - - /* If this is an inlined external function that has been marked uninlinable, - drop the body and stop there. Otherwise compile the body. */ - if (DECL_EXTERNAL (gnu_subprog_decl) && DECL_UNINLINABLE (gnu_subprog_decl)) - DECL_SAVED_TREE (gnu_subprog_decl) = NULL_TREE; - else - rest_of_subprog_body_compilation (gnu_subprog_decl); -} - -/* The type of an atomic access. */ - -typedef enum { NOT_ATOMIC, SIMPLE_ATOMIC, OUTER_ATOMIC } atomic_acces_t; - -/* Return true if GNAT_NODE references an Atomic entity. This is modeled on - the Is_Atomic_Object predicate of the front-end, but additionally handles - explicit dereferences. */ - -static bool -node_is_atomic (Node_Id gnat_node) -{ - Entity_Id gnat_entity; - - switch (Nkind (gnat_node)) - { - case N_Identifier: - case N_Expanded_Name: - gnat_entity = Entity (gnat_node); - if (Ekind (gnat_entity) != E_Variable) - break; - return Is_Atomic (gnat_entity) || Is_Atomic (Etype (gnat_entity)); - - case N_Selected_Component: - return Is_Atomic (Etype (gnat_node)) - || Is_Atomic (Entity (Selector_Name (gnat_node))); - - case N_Indexed_Component: - return Is_Atomic (Etype (gnat_node)) - || Has_Atomic_Components (Etype (Prefix (gnat_node))) - || (Is_Entity_Name (Prefix (gnat_node)) - && Has_Atomic_Components (Entity (Prefix (gnat_node)))); - - case N_Explicit_Dereference: - return Is_Atomic (Etype (gnat_node)); - - default: - break; - } - - return false; -} - -/* Return true if GNAT_NODE references a Volatile_Full_Access entity. This is - modeled on the Is_Volatile_Full_Access_Object predicate of the front-end, - but additionally handles explicit dereferences. */ - -static bool -node_is_volatile_full_access (Node_Id gnat_node) -{ - Entity_Id gnat_entity; - - switch (Nkind (gnat_node)) - { - case N_Identifier: - case N_Expanded_Name: - gnat_entity = Entity (gnat_node); - if (!Is_Object (gnat_entity)) - break; - return Is_Volatile_Full_Access (gnat_entity) - || Is_Volatile_Full_Access (Etype (gnat_entity)); - - case N_Selected_Component: - return Is_Volatile_Full_Access (Etype (gnat_node)) - || Is_Volatile_Full_Access (Entity (Selector_Name (gnat_node))); - - case N_Indexed_Component: - case N_Explicit_Dereference: - return Is_Volatile_Full_Access (Etype (gnat_node)); - - default: - break; - } - - return false; -} - -/* Return true if GNAT_NODE references a component of a larger object. */ - -static inline bool -node_is_component (Node_Id gnat_node) -{ - const Node_Kind k = Nkind (gnat_node); - return - (k == N_Indexed_Component || k == N_Selected_Component || k == N_Slice); -} - -/* Compute whether GNAT_NODE requires atomic access and set TYPE to the type - of access and SYNC according to the associated synchronization setting. - - We implement 3 different semantics of atomicity in this function: - - 1. the Ada 95/2005/2012 semantics of the Atomic aspect/pragma, - 2. the Ada 2022 semantics of the Atomic aspect/pragma, - 3. the semantics of the Volatile_Full_Access GNAT aspect/pragma. - - They are mutually exclusive and the FE should have rejected conflicts. */ - -static void -get_atomic_access (Node_Id gnat_node, atomic_acces_t *type, bool *sync) -{ - Node_Id gnat_parent, gnat_temp; - unsigned char attr_id; - - /* First, scan the parent to filter out irrelevant cases. */ - gnat_parent = Parent (gnat_node); - switch (Nkind (gnat_parent)) - { - case N_Attribute_Reference: - attr_id = Get_Attribute_Id (Attribute_Name (gnat_parent)); - /* Do not mess up machine code insertions. */ - if (attr_id == Attr_Asm_Input || attr_id == Attr_Asm_Output) - goto not_atomic; - - /* Nothing to do if we are the prefix of an attribute, since we do not - want an atomic access for things like 'Size. */ - - /* ... fall through ... */ - - case N_Reference: - /* The N_Reference node is like an attribute. */ - if (Prefix (gnat_parent) == gnat_node) - goto not_atomic; - break; - - case N_Object_Renaming_Declaration: - /* Nothing to do for the identifier in an object renaming declaration, - the renaming itself does not need atomic access. */ - goto not_atomic; - - default: - break; - } - - /* Now strip any type conversion from GNAT_NODE. */ - if (Nkind (gnat_node) == N_Type_Conversion - || Nkind (gnat_node) == N_Unchecked_Type_Conversion) - gnat_node = Expression (gnat_node); - - /* Up to Ada 2012, for Atomic itself, only reads and updates of the object as - a whole require atomic access (RM C.6(15)). But, starting with Ada 2022, - reads of or writes to a nonatomic subcomponent of the object also require - atomic access (RM C.6(19)). */ - if (node_is_atomic (gnat_node)) - { - bool as_a_whole = true; - - /* If we are the prefix of the parent, then the access is partial. */ - for (gnat_temp = gnat_node, gnat_parent = Parent (gnat_temp); - node_is_component (gnat_parent) && Prefix (gnat_parent) == gnat_temp; - gnat_temp = gnat_parent, gnat_parent = Parent (gnat_temp)) - if (Ada_Version < Ada_2022 || node_is_atomic (gnat_parent)) - goto not_atomic; - else - as_a_whole = false; - - /* We consider that partial accesses are not sequential actions and, - therefore, do not require synchronization. */ - *type = SIMPLE_ATOMIC; - *sync = as_a_whole ? Atomic_Sync_Required (gnat_node) : false; - return; - } - - /* Look for an outer atomic access of a nonatomic subcomponent. Note that, - for VFA, we do this before looking at the node itself because we need to - access the outermost VFA object atomically, unlike for Atomic where it is - the innermost atomic object (RM C.6(19)). */ - for (gnat_temp = gnat_node; - node_is_component (gnat_temp); - gnat_temp = Prefix (gnat_temp)) - if ((Ada_Version >= Ada_2022 && node_is_atomic (Prefix (gnat_temp))) - || node_is_volatile_full_access (Prefix (gnat_temp))) - { - *type = OUTER_ATOMIC; - *sync = false; - return; - } - - /* Unlike Atomic, accessing a VFA object always requires atomic access. */ - if (node_is_volatile_full_access (gnat_node)) - { - *type = SIMPLE_ATOMIC; - *sync = false; - return; - } - -not_atomic: - *type = NOT_ATOMIC; - *sync = false; -} - -/* Return true if GNAT_NODE requires simple atomic access and, if so, set SYNC - according to the associated synchronization setting. */ - -static inline bool -simple_atomic_access_required_p (Node_Id gnat_node, bool *sync) -{ - atomic_acces_t type; - get_atomic_access (gnat_node, &type, sync); - return type == SIMPLE_ATOMIC; -} - -/* Create a temporary variable with PREFIX and TYPE, and return it. */ - -static tree -create_temporary (const char *prefix, tree type) -{ - tree gnu_temp - = create_var_decl (create_tmp_var_name (prefix), NULL_TREE, - type, NULL_TREE, - false, false, false, false, false, - true, false, NULL, Empty); - return gnu_temp; -} - -/* Create a temporary variable with PREFIX and initialize it with GNU_INIT. - Put the initialization statement into GNU_INIT_STMT and annotate it with - the SLOC of GNAT_NODE. Return the temporary variable. */ - -static tree -create_init_temporary (const char *prefix, tree gnu_init, tree *gnu_init_stmt, - Node_Id gnat_node) -{ - tree gnu_temp = create_temporary (prefix, TREE_TYPE (gnu_init)); - - *gnu_init_stmt = build_binary_op (INIT_EXPR, NULL_TREE, gnu_temp, gnu_init); - set_expr_location_from_node (*gnu_init_stmt, gnat_node); - - return gnu_temp; -} - -/* Return true if TYPE is an array of scalar type. */ - -static bool -is_array_of_scalar_type (tree type) -{ - if (TREE_CODE (type) != ARRAY_TYPE) - return false; - - type = TREE_TYPE (type); - - return !AGGREGATE_TYPE_P (type) && !POINTER_TYPE_P (type); -} - -/* Helper function for walk_tree, used by return_slot_opt_for_pure_call_p. */ - -static tree -find_decls_r (tree *tp, int *walk_subtrees, void *data) -{ - bitmap decls = (bitmap) data; - - if (TYPE_P (*tp)) - *walk_subtrees = 0; - - else if (DECL_P (*tp)) - bitmap_set_bit (decls, DECL_UID (*tp)); - - return NULL_TREE; -} - -/* Return whether the assignment TARGET = CALL can be subject to the return - slot optimization, under the assumption that the called function be pure - in the Ada sense and return an array of scalar type. */ - -static bool -return_slot_opt_for_pure_call_p (tree target, tree call) -{ - /* Check that the target is a DECL. */ - if (!DECL_P (target)) - return false; - - const bitmap decls = BITMAP_GGC_ALLOC (); - call_expr_arg_iterator iter; - tree arg; - - /* Check that all the arguments have either a scalar type (we assume that - this means by-copy passing mechanism) or array of scalar type. */ - FOR_EACH_CALL_EXPR_ARG (arg, iter, call) - { - tree arg_type = TREE_TYPE (arg); - if (TREE_CODE (arg_type) == REFERENCE_TYPE) - arg_type = TREE_TYPE (arg_type); - - if (is_array_of_scalar_type (arg_type)) - walk_tree_without_duplicates (&arg, find_decls_r, decls); - - else if (AGGREGATE_TYPE_P (arg_type) || POINTER_TYPE_P (arg_type)) - return false; - } - - /* Check that the target is not referenced by the non-scalar arguments. */ - return !bitmap_bit_p (decls, DECL_UID (target)); -} - -/* Elaborate types referenced in the profile (FIRST_FORMAL, RESULT_TYPE). */ - -static void -elaborate_profile (Entity_Id first_formal, Entity_Id result_type) -{ - Entity_Id formal; - - for (formal = first_formal; - Present (formal); - formal = Next_Formal_With_Extras (formal)) - (void) gnat_to_gnu_type (Etype (formal)); - - if (Present (result_type) && Ekind (result_type) != E_Void) - (void) gnat_to_gnu_type (result_type); -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, either an N_Function_Call - or an N_Procedure_Call_Statement, to a GCC tree, which is returned. - GNU_RESULT_TYPE_P is a pointer to where we should place the result type. - If GNU_TARGET is non-null, this must be a function call on the RHS of a - N_Assignment_Statement and the result is to be placed into that object. - ATOMIC_ACCESS is the type of atomic access to be used for the assignment - to GNU_TARGET. If, in addition, ATOMIC_SYNC is true, then the assignment - to GNU_TARGET requires atomic synchronization. */ - -static tree -Call_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p, tree gnu_target, - atomic_acces_t atomic_access, bool atomic_sync) -{ - const bool function_call = (Nkind (gnat_node) == N_Function_Call); - const bool returning_value = (function_call && !gnu_target); - /* The GCC node corresponding to the GNAT subprogram name. This can either - be a FUNCTION_DECL node if we are dealing with a standard subprogram call, - or an indirect reference expression (an INDIRECT_REF node) pointing to a - subprogram. */ - const Node_Id gnat_subprog = Name (gnat_node); - tree gnu_subprog = gnat_to_gnu (gnat_subprog); - /* The FUNCTION_TYPE node giving the GCC type of the subprogram. */ - tree gnu_subprog_type = TREE_TYPE (gnu_subprog); - /* The return type of the FUNCTION_TYPE. */ - tree gnu_result_type;; - const bool frontend_builtin - = (TREE_CODE (gnu_subprog) == FUNCTION_DECL - && DECL_BUILT_IN_CLASS (gnu_subprog) == BUILT_IN_FRONTEND); - auto_vec<tree, 16> gnu_actual_vec; - tree gnu_name_list = NULL_TREE; - tree gnu_stmt_list = NULL_TREE; - tree gnu_after_list = NULL_TREE; - tree gnu_retval = NULL_TREE; - tree gnu_call, gnu_result; - bool went_into_elab_proc; - bool pushed_binding_level; - bool variadic; - bool by_descriptor; - Entity_Id gnat_formal; - Entity_Id gnat_result_type; - Node_Id gnat_actual; - atomic_acces_t aa_type; - bool aa_sync; - - /* The only way we can make a call via an access type is if GNAT_NAME is an - explicit dereference. In that case, get the list of formal args from the - type the access type is pointing to. Otherwise, get the formals from the - entity being called. */ - if (Nkind (gnat_subprog) == N_Explicit_Dereference) - { - const Entity_Id gnat_prefix_type - = Underlying_Type (Etype (Prefix (gnat_subprog))); - - gnat_formal = First_Formal_With_Extras (Etype (gnat_subprog)); - gnat_result_type = Etype (Etype (gnat_subprog)); - variadic = IN (Convention (gnat_prefix_type), Convention_C_Variadic); - - /* If the access type doesn't require foreign-compatible representation, - be prepared for descriptors. */ - by_descriptor - = targetm.calls.custom_function_descriptors > 0 - && Can_Use_Internal_Rep (gnat_prefix_type); - } - - else if (Nkind (gnat_subprog) == N_Attribute_Reference) - { - /* Assume here that this must be 'Elab_Body or 'Elab_Spec. */ - gnat_formal = Empty; - gnat_result_type = Empty; - variadic = false; - by_descriptor = false; - } - - else - { - gcc_checking_assert (Is_Entity_Name (gnat_subprog)); - - gnat_formal = First_Formal_With_Extras (Entity (gnat_subprog)); - gnat_result_type = Etype (Entity_Id (gnat_subprog)); - variadic = IN (Convention (Entity (gnat_subprog)), Convention_C_Variadic); - by_descriptor = false; - - /* If we are calling a stubbed function, then raise Program_Error, but - elaborate all our args first. */ - if (Convention (Entity (gnat_subprog)) == Convention_Stubbed) - { - tree call_expr = build_call_raise (PE_Stubbed_Subprogram_Called, - gnat_node, N_Raise_Program_Error); - - for (gnat_actual = First_Actual (gnat_node); - Present (gnat_actual); - gnat_actual = Next_Actual (gnat_actual)) - add_stmt (gnat_to_gnu (gnat_actual)); - - if (returning_value) - { - gnu_result_type = TREE_TYPE (gnu_subprog_type); - *gnu_result_type_p = gnu_result_type; - return build1 (NULL_EXPR, gnu_result_type, call_expr); - } - - return call_expr; - } - } - - /* We must elaborate the entire profile now because, if it references types - that were initially incomplete,, their elaboration changes the contents - of GNU_SUBPROG_TYPE and, in particular, may change the result type. */ - elaborate_profile (gnat_formal, gnat_result_type); - - gcc_assert (FUNC_OR_METHOD_TYPE_P (gnu_subprog_type)); - gnu_result_type = TREE_TYPE (gnu_subprog_type); - - if (TREE_CODE (gnu_subprog) == FUNCTION_DECL) - { - /* For a call to a nested function, check the inlining status. */ - if (decl_function_context (gnu_subprog)) - check_inlining_for_nested_subprog (gnu_subprog); - - /* For a recursive call, avoid explosion due to recursive inlining. */ - if (gnu_subprog == current_function_decl) - DECL_DISREGARD_INLINE_LIMITS (gnu_subprog) = 0; - } - - /* The lifetime of the temporaries created for the call ends right after the - return value is copied, so we can give them the scope of the elaboration - routine at top level. */ - if (!current_function_decl) - { - current_function_decl = get_elaboration_procedure (); - went_into_elab_proc = true; - } - else - went_into_elab_proc = false; - - /* First, create the temporary for the return value when: - - 1. There is no target and the function has copy-in/copy-out parameters, - because we need to preserve the return value before copying back the - parameters. - - 2. There is no target and the call is made for neither the declaration - of an object (regular or renaming), nor a return statement, nor an - allocator, nor an aggregate, and the return type has variable size - because in this case the gimplifier cannot create the temporary, or - more generally is an aggregate type, because the gimplifier would - create the temporary in the outermost scope instead of locally here. - But there is an exception for an allocator of unconstrained record - type with default discriminant because we allocate the actual size - in this case, unlike in the other cases, so we need a temporary to - fetch the discriminant and we create it here. - - 3. There is a target and it is a slice or an array with fixed size, - and the return type has variable size, because the gimplifier - doesn't handle these cases. - - 4. There is a target which is a bit-field and the function returns an - unconstrained record type with default discriminant, because the - return may copy more data than the bit-field can contain. - - 5. There is no target and we have misaligned In Out or Out parameters - passed by reference, because we need to preserve the return value - before copying back the parameters. However, in this case, we'll - defer creating the temporary, see below. - - This must be done before we push a binding level around the call, since - we will pop it before copying the return value. */ - if (function_call - && ((!gnu_target && TYPE_CI_CO_LIST (gnu_subprog_type)) - || (!gnu_target - && Nkind (Parent (gnat_node)) != N_Object_Declaration - && Nkind (Parent (gnat_node)) != N_Object_Renaming_Declaration - && Nkind (Parent (gnat_node)) != N_Simple_Return_Statement - && (!(Nkind (Parent (gnat_node)) == N_Qualified_Expression - && Nkind (Parent (Parent (gnat_node))) == N_Allocator) - || type_is_padding_self_referential (gnu_result_type)) - && Nkind (Parent (gnat_node)) != N_Aggregate - && AGGREGATE_TYPE_P (gnu_result_type) - && !TYPE_IS_FAT_POINTER_P (gnu_result_type)) - || (gnu_target - && (TREE_CODE (gnu_target) == ARRAY_RANGE_REF - || (TREE_CODE (TREE_TYPE (gnu_target)) == ARRAY_TYPE - && TREE_CODE (TYPE_SIZE (TREE_TYPE (gnu_target))) - == INTEGER_CST)) - && TREE_CODE (TYPE_SIZE (gnu_result_type)) != INTEGER_CST) - || (gnu_target - && TREE_CODE (gnu_target) == COMPONENT_REF - && DECL_BIT_FIELD (TREE_OPERAND (gnu_target, 1)) - && DECL_SIZE (TREE_OPERAND (gnu_target, 1)) - != TYPE_SIZE (TREE_TYPE (gnu_target)) - && type_is_padding_self_referential (gnu_result_type)))) - { - gnu_retval = create_temporary ("R", gnu_result_type); - DECL_RETURN_VALUE_P (gnu_retval) = 1; - } - - /* If we don't need a value or have already created it, push a binding level - around the call. This will narrow the lifetime of the temporaries we may - need to make when translating the parameters as much as possible. */ - if (!returning_value || gnu_retval) - { - start_stmt_group (); - gnat_pushlevel (); - pushed_binding_level = true; - } - else - pushed_binding_level = false; - - /* Create the list of the actual parameters as GCC expects it, namely a - chain of TREE_LIST nodes in which the TREE_VALUE field of each node - is an expression and the TREE_PURPOSE field is null. But skip Out - parameters not passed by reference and that need not be copied in. */ - for (gnat_actual = First_Actual (gnat_node); - Present (gnat_actual); - gnat_formal = Next_Formal_With_Extras (gnat_formal), - gnat_actual = Next_Actual (gnat_actual)) - { - Entity_Id gnat_formal_type = Etype (gnat_formal); - tree gnu_formal_type = gnat_to_gnu_type (gnat_formal_type); - tree gnu_formal = present_gnu_tree (gnat_formal) - ? get_gnu_tree (gnat_formal) : NULL_TREE; - const bool in_param = (Ekind (gnat_formal) == E_In_Parameter); - const bool is_true_formal_parm - = gnu_formal && TREE_CODE (gnu_formal) == PARM_DECL; - const bool is_by_ref_formal_parm - = is_true_formal_parm - && (DECL_BY_REF_P (gnu_formal) - || DECL_BY_COMPONENT_PTR_P (gnu_formal)); - /* In the In Out or Out case, we must suppress conversions that yield - an lvalue but can nevertheless cause the creation of a temporary, - because we need the real object in this case, either to pass its - address if it's passed by reference or as target of the back copy - done after the call if it uses the copy-in/copy-out mechanism. - We do it in the In case too, except for an unchecked conversion - to an elementary type or a constrained composite type because it - alone can cause the actual to be misaligned and the addressability - test is applied to the real object. */ - const bool suppress_type_conversion - = ((Nkind (gnat_actual) == N_Unchecked_Type_Conversion - && (!in_param - || !is_by_ref_formal_parm - || (Is_Composite_Type (Underlying_Type (gnat_formal_type)) - && !Is_Constrained (Underlying_Type (gnat_formal_type))))) - || (Nkind (gnat_actual) == N_Type_Conversion - && Is_Composite_Type (Underlying_Type (gnat_formal_type)))); - Node_Id gnat_name = suppress_type_conversion - ? Expression (gnat_actual) : gnat_actual; - tree gnu_name = gnat_to_gnu (gnat_name), gnu_name_type; - - /* If it's possible we may need to use this expression twice, make sure - that any side-effects are handled via SAVE_EXPRs; likewise if we need - to force side-effects before the call. */ - if (!in_param && !is_by_ref_formal_parm) - { - tree init = NULL_TREE; - gnu_name = gnat_stabilize_reference (gnu_name, true, &init); - if (init) - gnu_name - = build_compound_expr (TREE_TYPE (gnu_name), init, gnu_name); - } - - /* If we are passing a non-addressable parameter by reference, pass the - address of a copy. In the In Out or Out case, set up to copy back - out after the call. */ - if (is_by_ref_formal_parm - && (gnu_name_type = gnat_to_gnu_type (Etype (gnat_name))) - && !addressable_p (gnu_name, gnu_name_type)) - { - tree gnu_orig = gnu_name, gnu_temp, gnu_stmt; - - /* Do not issue warnings for CONSTRUCTORs since this is not a copy - but sort of an instantiation for them. */ - if (TREE_CODE (remove_conversions (gnu_name, true)) == CONSTRUCTOR) - ; - - /* If the formal is passed by reference, a copy is not allowed. */ - else if (TYPE_IS_BY_REFERENCE_P (gnu_formal_type) - || Is_Aliased (gnat_formal)) - post_error ("misaligned actual cannot be passed by reference", - gnat_actual); - - /* If the mechanism was forced to by-ref, a copy is not allowed but - we issue only a warning because this case is not strict Ada. */ - else if (DECL_FORCED_BY_REF_P (gnu_formal)) - post_error ("misaligned actual cannot be passed by reference??", - gnat_actual); - - /* If the actual type of the object is already the nominal type, - we have nothing to do, except if the size is self-referential - in which case we'll remove the unpadding below. */ - if (TREE_TYPE (gnu_name) == gnu_name_type - && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_name_type))) - ; - - /* Otherwise remove the unpadding from all the objects. */ - else if (TREE_CODE (gnu_name) == COMPONENT_REF - && TYPE_IS_PADDING_P - (TREE_TYPE (TREE_OPERAND (gnu_name, 0)))) - gnu_orig = gnu_name = TREE_OPERAND (gnu_name, 0); - - /* Otherwise convert to the nominal type of the object if needed. - There are several cases in which we need to make the temporary - using this type instead of the actual type of the object when - they are distinct, because the expectations of the callee would - otherwise not be met: - - if it's a justified modular type, - - if the actual type is a smaller form of it, - - if it's a smaller form of the actual type. */ - else if ((TREE_CODE (gnu_name_type) == RECORD_TYPE - && (TYPE_JUSTIFIED_MODULAR_P (gnu_name_type) - || smaller_form_type_p (TREE_TYPE (gnu_name), - gnu_name_type))) - || (INTEGRAL_TYPE_P (gnu_name_type) - && smaller_form_type_p (gnu_name_type, - TREE_TYPE (gnu_name)))) - gnu_name = convert (gnu_name_type, gnu_name); - - /* If this is an In Out or Out parameter and we're returning a value, - we need to create a temporary for the return value because we must - preserve it before copying back at the very end. */ - if (!in_param && returning_value && !gnu_retval) - { - gnu_retval = create_temporary ("R", gnu_result_type); - DECL_RETURN_VALUE_P (gnu_retval) = 1; - } - - /* If we haven't pushed a binding level, push it now. This will - narrow the lifetime of the temporary we are about to make as - much as possible. */ - if (!pushed_binding_level && (!returning_value || gnu_retval)) - { - start_stmt_group (); - gnat_pushlevel (); - pushed_binding_level = true; - } - - /* Create an explicit temporary holding the copy. */ - /* Do not initialize it for the _Init parameter of an initialization - procedure since no data is meant to be passed in. */ - if (Ekind (gnat_formal) == E_Out_Parameter - && Is_Entity_Name (gnat_subprog) - && Is_Init_Proc (Entity (gnat_subprog))) - gnu_name = gnu_temp = create_temporary ("A", TREE_TYPE (gnu_name)); - - /* Initialize it on the fly like for an implicit temporary in the - other cases, as we don't necessarily have a statement list. */ - else - { - gnu_temp = create_init_temporary ("A", gnu_name, &gnu_stmt, - gnat_actual); - gnu_name = build_compound_expr (TREE_TYPE (gnu_name), gnu_stmt, - gnu_temp); - } - - /* Set up to move the copy back to the original if needed. */ - if (!in_param) - { - /* If the original is a COND_EXPR whose first arm isn't meant to - be further used, just deal with the second arm. This is very - likely the conditional expression built for a check. */ - if (TREE_CODE (gnu_orig) == COND_EXPR - && TREE_CODE (TREE_OPERAND (gnu_orig, 1)) == COMPOUND_EXPR - && integer_zerop - (TREE_OPERAND (TREE_OPERAND (gnu_orig, 1), 1))) - gnu_orig = TREE_OPERAND (gnu_orig, 2); - - gnu_stmt - = build_binary_op (MODIFY_EXPR, NULL_TREE, gnu_orig, gnu_temp); - set_expr_location_from_node (gnu_stmt, gnat_node); - - append_to_statement_list (gnu_stmt, &gnu_after_list); - } - } - - /* Start from the real object and build the actual. */ - tree gnu_actual = gnu_name; - - /* If atomic access is required for an In or In Out actual parameter, - build the atomic load. */ - if (is_true_formal_parm - && !is_by_ref_formal_parm - && Ekind (gnat_formal) != E_Out_Parameter - && simple_atomic_access_required_p (gnat_actual, &aa_sync)) - gnu_actual = build_atomic_load (gnu_actual, aa_sync); - - /* If this was a procedure call, we may not have removed any padding. - So do it here for the part we will use as an input, if any. */ - if (Ekind (gnat_formal) != E_Out_Parameter - && TYPE_IS_PADDING_P (TREE_TYPE (gnu_actual))) - gnu_actual - = convert (get_unpadded_type (Etype (gnat_actual)), gnu_actual); - - /* Put back the conversion we suppressed above in the computation of the - real object. And even if we didn't suppress any conversion there, we - may have suppressed a conversion to the Etype of the actual earlier, - since the parent is a procedure call, so put it back here. Note that - we might have a dummy type here if the actual is the dereference of a - pointer to it, but that's OK when the formal is passed by reference. - We also do not put back a conversion between an actual and a formal - that are unconstrained array types to avoid creating local bounds. */ - tree gnu_actual_type = get_unpadded_type (Etype (gnat_actual)); - if (TYPE_IS_DUMMY_P (gnu_actual_type)) - gcc_assert (is_true_formal_parm && DECL_BY_REF_P (gnu_formal)); - else if (suppress_type_conversion - && Nkind (gnat_actual) == N_Unchecked_Type_Conversion) - gnu_actual = unchecked_convert (gnu_actual_type, gnu_actual, - No_Truncation (gnat_actual)); - else if ((TREE_CODE (TREE_TYPE (gnu_actual)) == UNCONSTRAINED_ARRAY_TYPE - || (TREE_CODE (TREE_TYPE (gnu_actual)) == RECORD_TYPE - && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (gnu_actual)))) - && TREE_CODE (gnu_formal_type) == UNCONSTRAINED_ARRAY_TYPE) - ; - else - gnu_actual = convert (gnu_actual_type, gnu_actual); - - gigi_checking_assert (!Do_Range_Check (gnat_actual)); - - /* First see if the parameter is passed by reference. */ - if (is_true_formal_parm && DECL_BY_REF_P (gnu_formal)) - { - if (!in_param) - { - /* In Out or Out parameters passed by reference don't use the - copy-in/copy-out mechanism so the address of the real object - must be passed to the function. */ - gnu_actual = gnu_name; - - /* If we have a padded type, be sure we've removed padding. */ - if (TYPE_IS_PADDING_P (TREE_TYPE (gnu_actual))) - gnu_actual = convert (get_unpadded_type (Etype (gnat_actual)), - gnu_actual); - - /* If we have the constructed subtype of an aliased object - with an unconstrained nominal subtype, the type of the - actual includes the template, although it is formally - constrained. So we need to convert it back to the real - constructed subtype to retrieve the constrained part - and takes its address. */ - if (TREE_CODE (TREE_TYPE (gnu_actual)) == RECORD_TYPE - && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (gnu_actual)) - && Is_Constr_Subt_For_UN_Aliased (Etype (gnat_actual)) - && Is_Array_Type (Underlying_Type (Etype (gnat_actual)))) - gnu_actual = convert (gnu_actual_type, gnu_actual); - } - - /* There is no need to convert the actual to the formal's type before - taking its address. The only exception is for unconstrained array - types because of the way we build fat pointers. */ - if (TREE_CODE (gnu_formal_type) == UNCONSTRAINED_ARRAY_TYPE) - { - /* Put back the conversion we suppressed above for In Out or Out - parameters, since it may set the bounds of the actual. */ - if (!in_param && suppress_type_conversion) - gnu_actual = convert (gnu_actual_type, gnu_actual); - gnu_actual = convert (gnu_formal_type, gnu_actual); - } - - /* Take the address of the object and convert to the proper pointer - type. */ - gnu_formal_type = TREE_TYPE (gnu_formal); - gnu_actual = build_unary_op (ADDR_EXPR, gnu_formal_type, gnu_actual); - } - - /* Then see if the parameter is an array passed to a foreign convention - subprogram. */ - else if (is_true_formal_parm && DECL_BY_COMPONENT_PTR_P (gnu_formal)) - { - gnu_actual = maybe_padded_object (gnu_actual); - gnu_actual = maybe_unconstrained_array (gnu_actual); - - /* Take the address of the object and convert to the proper pointer - type. We'd like to actually compute the address of the beginning - of the array using an ADDR_EXPR of an ARRAY_REF, but there's a - possibility that the ARRAY_REF might return a constant and we'd be - getting the wrong address. Neither approach is exactly correct, - but this is the most likely to work in all cases. */ - gnu_formal_type = TREE_TYPE (gnu_formal); - gnu_actual = build_unary_op (ADDR_EXPR, gnu_formal_type, gnu_actual); - } - - /* Then see if the parameter is passed by copy. */ - else if (is_true_formal_parm) - { - if (!in_param) - gnu_name_list = tree_cons (NULL_TREE, gnu_name, gnu_name_list); - - gnu_actual = convert (gnu_formal_type, gnu_actual); - - /* If this is a front-end built-in function, there is no need to - convert to the type used to pass the argument. */ - if (!frontend_builtin) - gnu_actual = convert (DECL_ARG_TYPE (gnu_formal), gnu_actual); - } - - /* Then see if this is an unnamed parameter in a variadic C function. */ - else if (variadic) - { - /* This is based on the processing done in gnat_to_gnu_param, but - we expect the mechanism to be set in (almost) all cases. */ - const Mechanism_Type mech = Mechanism (gnat_formal); - - /* Strip off possible padding type. */ - if (TYPE_IS_PADDING_P (gnu_formal_type)) - gnu_formal_type = TREE_TYPE (TYPE_FIELDS (gnu_formal_type)); - - /* Arrays are passed as pointers to element type. First check for - unconstrained array and get the underlying array. */ - if (TREE_CODE (gnu_formal_type) == UNCONSTRAINED_ARRAY_TYPE) - gnu_formal_type - = TREE_TYPE - (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_formal_type)))); - - /* Arrays are passed as pointers to element type. */ - if (mech != By_Copy && TREE_CODE (gnu_formal_type) == ARRAY_TYPE) - { - gnu_actual = maybe_padded_object (gnu_actual); - gnu_actual = maybe_unconstrained_array (gnu_actual); - - /* Strip off any multi-dimensional entries, then strip - off the last array to get the component type. */ - while (TREE_CODE (TREE_TYPE (gnu_formal_type)) == ARRAY_TYPE - && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_formal_type))) - gnu_formal_type = TREE_TYPE (gnu_formal_type); - - gnu_formal_type = TREE_TYPE (gnu_formal_type); - gnu_formal_type = build_pointer_type (gnu_formal_type); - gnu_actual - = build_unary_op (ADDR_EXPR, gnu_formal_type, gnu_actual); - } - - /* Fat pointers are passed as thin pointers. */ - else if (TYPE_IS_FAT_POINTER_P (gnu_formal_type)) - gnu_formal_type - = make_type_from_size (gnu_formal_type, - size_int (POINTER_SIZE), 0); - - /* If we were requested or muss pass by reference, do so. - If we were requested to pass by copy, do so. - Otherwise, pass In Out or Out parameters or aggregates by - reference. */ - else if (mech == By_Reference - || must_pass_by_ref (gnu_formal_type) - || (mech != By_Copy - && (!in_param || AGGREGATE_TYPE_P (gnu_formal_type)))) - { - gnu_formal_type = build_reference_type (gnu_formal_type); - gnu_actual - = build_unary_op (ADDR_EXPR, gnu_formal_type, gnu_actual); - } - - /* Otherwise pass by copy after applying default C promotions. */ - else - { - if (INTEGRAL_TYPE_P (gnu_formal_type) - && TYPE_PRECISION (gnu_formal_type) - < TYPE_PRECISION (integer_type_node)) - gnu_formal_type = integer_type_node; - - else if (SCALAR_FLOAT_TYPE_P (gnu_formal_type) - && TYPE_PRECISION (gnu_formal_type) - < TYPE_PRECISION (double_type_node)) - gnu_formal_type = double_type_node; - } - - gnu_actual = convert (gnu_formal_type, gnu_actual); - } - - /* If we didn't create a PARM_DECL for the formal, this means that - it is an Out parameter not passed by reference and that need not - be copied in. In this case, the value of the actual need not be - read. However, we still need to make sure that its side-effects - are evaluated before the call, so we evaluate its address. */ - else - { - if (!in_param) - gnu_name_list = tree_cons (NULL_TREE, gnu_name, gnu_name_list); - - if (TREE_SIDE_EFFECTS (gnu_name)) - { - tree addr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_name); - append_to_statement_list (addr, &gnu_stmt_list); - } - - continue; - } - - gnu_actual_vec.safe_push (gnu_actual); - } - - if (frontend_builtin) - { - tree pred_cst = build_int_cst (integer_type_node, PRED_BUILTIN_EXPECT); - enum internal_fn icode = IFN_BUILTIN_EXPECT; - - switch (DECL_FE_FUNCTION_CODE (gnu_subprog)) - { - case BUILT_IN_EXPECT: - break; - case BUILT_IN_LIKELY: - gnu_actual_vec.safe_push (boolean_true_node); - break; - case BUILT_IN_UNLIKELY: - gnu_actual_vec.safe_push (boolean_false_node); - break; - default: - gcc_unreachable (); - } - - gnu_actual_vec.safe_push (pred_cst); - - gnu_call - = build_call_expr_internal_loc_array (UNKNOWN_LOCATION, - icode, - gnu_result_type, - gnu_actual_vec.length (), - gnu_actual_vec.begin ()); - } - else - { - gnu_call - = build_call_array_loc (UNKNOWN_LOCATION, - gnu_result_type, - build_unary_op (ADDR_EXPR, NULL_TREE, - gnu_subprog), - gnu_actual_vec.length (), - gnu_actual_vec.begin ()); - CALL_EXPR_BY_DESCRIPTOR (gnu_call) = by_descriptor; - } - - set_expr_location_from_node (gnu_call, gnat_node); - - /* If we have created a temporary for the return value, initialize it. */ - if (gnu_retval) - { - tree gnu_stmt - = build_binary_op (INIT_EXPR, NULL_TREE, gnu_retval, gnu_call); - set_expr_location_from_node (gnu_stmt, gnat_node); - append_to_statement_list (gnu_stmt, &gnu_stmt_list); - gnu_call = gnu_retval; - } - - /* If this is a subprogram with copy-in/copy-out parameters, we need to - unpack the valued returned from the function into the In Out or Out - parameters. We deal with the function return (if this is an Ada - function) below. */ - if (TYPE_CI_CO_LIST (gnu_subprog_type)) - { - /* List of FIELD_DECLs associated with the PARM_DECLs of the copy-in/ - copy-out parameters. */ - tree gnu_cico_list = TYPE_CI_CO_LIST (gnu_subprog_type); - const int length = list_length (gnu_cico_list); - - /* The call sequence must contain one and only one call, even though the - function is pure. Save the result into a temporary if needed. */ - if (length > 1) - { - if (!gnu_retval) - { - tree gnu_stmt; - gnu_call - = create_init_temporary ("P", gnu_call, &gnu_stmt, gnat_node); - append_to_statement_list (gnu_stmt, &gnu_stmt_list); - } - - gnu_name_list = nreverse (gnu_name_list); - } - - /* The first entry is for the actual return value if this is a - function, so skip it. */ - if (function_call) - gnu_cico_list = TREE_CHAIN (gnu_cico_list); - - if (Nkind (gnat_subprog) == N_Explicit_Dereference) - gnat_formal = First_Formal_With_Extras (Etype (gnat_subprog)); - else - gnat_formal = First_Formal_With_Extras (Entity (gnat_subprog)); - - for (gnat_actual = First_Actual (gnat_node); - Present (gnat_actual); - gnat_formal = Next_Formal_With_Extras (gnat_formal), - gnat_actual = Next_Actual (gnat_actual)) - /* If we are dealing with a copy-in/copy-out parameter, we must - retrieve its value from the record returned in the call. */ - if (!(present_gnu_tree (gnat_formal) - && TREE_CODE (get_gnu_tree (gnat_formal)) == PARM_DECL - && (DECL_BY_REF_P (get_gnu_tree (gnat_formal)) - || DECL_BY_COMPONENT_PTR_P (get_gnu_tree (gnat_formal)))) - && Ekind (gnat_formal) != E_In_Parameter) - { - /* Get the value to assign to this In Out or Out parameter. It is - either the result of the function if there is only a single such - parameter or the appropriate field from the record returned. */ - tree gnu_result - = length == 1 - ? gnu_call - : build_component_ref (gnu_call, TREE_PURPOSE (gnu_cico_list), - false); - - /* If the actual is a conversion, get the inner expression, which - will be the real destination, and convert the result to the - type of the actual parameter. */ - tree gnu_actual - = maybe_unconstrained_array (TREE_VALUE (gnu_name_list)); - - /* If the result is padded, remove the padding. */ - gnu_result = maybe_padded_object (gnu_result); - - /* If the actual is a type conversion, the real target object is - denoted by the inner Expression and we need to convert the - result to the associated type. - We also need to convert our gnu assignment target to this type - if the corresponding GNU_NAME was constructed from the GNAT - conversion node and not from the inner Expression. */ - if (Nkind (gnat_actual) == N_Type_Conversion) - { - const Node_Id gnat_expr = Expression (gnat_actual); - - gigi_checking_assert (!Do_Range_Check (gnat_expr)); - - gnu_result - = convert_with_check (Etype (gnat_expr), gnu_result, - Do_Overflow_Check (gnat_actual), - Float_Truncate (gnat_actual), - gnat_actual); - - if (!Is_Composite_Type (Underlying_Type (Etype (gnat_formal)))) - gnu_actual = convert (TREE_TYPE (gnu_result), gnu_actual); - } - - /* Unchecked conversions as actuals for Out parameters are not - allowed in user code because they are not variables, but do - occur in front-end expansions. The associated GNU_NAME is - always obtained from the inner expression in such cases. */ - else if (Nkind (gnat_actual) == N_Unchecked_Type_Conversion) - gnu_result = unchecked_convert (TREE_TYPE (gnu_actual), - gnu_result, - No_Truncation (gnat_actual)); - else - { - gigi_checking_assert (!Do_Range_Check (gnat_actual)); - - if (!(!TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (gnu_actual))) - && TREE_CONSTANT (TYPE_SIZE (TREE_TYPE (gnu_result))))) - gnu_result = convert (TREE_TYPE (gnu_actual), gnu_result); - } - - get_atomic_access (gnat_actual, &aa_type, &aa_sync); - - /* If an outer atomic access is required for an actual parameter, - build the load-modify-store sequence. */ - if (aa_type == OUTER_ATOMIC) - gnu_result - = build_load_modify_store (gnu_actual, gnu_result, gnat_node); - - /* Or else, if a simple atomic access is required, build the atomic - store. */ - else if (aa_type == SIMPLE_ATOMIC) - gnu_result - = build_atomic_store (gnu_actual, gnu_result, aa_sync); - - /* Otherwise build a regular assignment. */ - else - gnu_result = build_binary_op (MODIFY_EXPR, NULL_TREE, - gnu_actual, gnu_result); - - if (EXPR_P (gnu_result)) - set_expr_location_from_node (gnu_result, gnat_node); - append_to_statement_list (gnu_result, &gnu_stmt_list); - gnu_cico_list = TREE_CHAIN (gnu_cico_list); - gnu_name_list = TREE_CHAIN (gnu_name_list); - } - } - - /* If this is a function call, the result is the call expression unless a - target is specified, in which case we copy the result into the target - and return the assignment statement. */ - if (function_call) - { - /* If this is a function with copy-in/copy-out parameters, extract the - return value from it and update the return type. */ - if (TYPE_CI_CO_LIST (gnu_subprog_type)) - { - tree gnu_elmt = TYPE_CI_CO_LIST (gnu_subprog_type); - gnu_call - = build_component_ref (gnu_call, TREE_PURPOSE (gnu_elmt), false); - gnu_result_type = TREE_TYPE (gnu_call); - } - - /* If the function returns an unconstrained array or by direct reference, - we have to dereference the pointer. */ - if (TYPE_RETURN_UNCONSTRAINED_P (gnu_subprog_type) - || TYPE_RETURN_BY_DIRECT_REF_P (gnu_subprog_type)) - gnu_call = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_call); - - if (gnu_target) - { - Node_Id gnat_parent = Parent (gnat_node); - enum tree_code op_code; - - gigi_checking_assert (!Do_Range_Check (gnat_node)); - - /* ??? If the return type has variable size, then force the return - slot optimization as we would not be able to create a temporary. - That's what has been done historically. */ - if (return_type_with_variable_size_p (gnu_result_type)) - op_code = INIT_EXPR; - - /* If this is a call to a pure function returning an array of scalar - type, try to apply the return slot optimization. */ - else if ((TYPE_READONLY (gnu_subprog_type) - || TYPE_RESTRICT (gnu_subprog_type)) - && is_array_of_scalar_type (gnu_result_type) - && TYPE_MODE (gnu_result_type) == BLKmode - && aggregate_value_p (gnu_result_type, gnu_subprog_type) - && return_slot_opt_for_pure_call_p (gnu_target, gnu_call)) - op_code = INIT_EXPR; - - else - op_code = MODIFY_EXPR; - - /* Use the required method to move the result to the target. */ - if (atomic_access == OUTER_ATOMIC) - gnu_call - = build_load_modify_store (gnu_target, gnu_call, gnat_node); - else if (atomic_access == SIMPLE_ATOMIC) - gnu_call = build_atomic_store (gnu_target, gnu_call, atomic_sync); - else - gnu_call - = build_binary_op (op_code, NULL_TREE, gnu_target, gnu_call); - - if (EXPR_P (gnu_call)) - set_expr_location_from_node (gnu_call, gnat_parent); - append_to_statement_list (gnu_call, &gnu_stmt_list); - } - else - *gnu_result_type_p = get_unpadded_type (Etype (gnat_node)); - } - - /* Otherwise, if this is a procedure call statement without copy-in/copy-out - parameters, the result is just the call statement. */ - else if (!TYPE_CI_CO_LIST (gnu_subprog_type)) - append_to_statement_list (gnu_call, &gnu_stmt_list); - - /* Finally, add the copy back statements, if any. */ - append_to_statement_list (gnu_after_list, &gnu_stmt_list); - - if (went_into_elab_proc) - current_function_decl = NULL_TREE; - - /* If we have pushed a binding level, pop it and finish up the enclosing - statement group. */ - if (pushed_binding_level) - { - add_stmt (gnu_stmt_list); - gnat_poplevel (); - gnu_result = end_stmt_group (); - } - - /* Otherwise, retrieve the statement list, if any. */ - else if (gnu_stmt_list) - gnu_result = gnu_stmt_list; - - /* Otherwise, just return the call expression. */ - else - return gnu_call; - - /* If we nevertheless need a value, make a COMPOUND_EXPR to return it. - But first simplify if we have only one statement in the list. */ - if (returning_value) - { - tree first = expr_first (gnu_result), last = expr_last (gnu_result); - if (first == last) - gnu_result = first; - gnu_result - = build_compound_expr (TREE_TYPE (gnu_call), gnu_result, gnu_call); - } - - return gnu_result; -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, an - N_Handled_Sequence_Of_Statements, to a GCC tree, which is returned. */ - -static tree -Handled_Sequence_Of_Statements_to_gnu (Node_Id gnat_node) -{ - /* If just annotating, ignore all EH and cleanups. */ - const bool gcc_eh - = (!type_annotate_only - && Present (Exception_Handlers (gnat_node)) - && Back_End_Exceptions ()); - const bool fe_sjlj_eh - = (!type_annotate_only - && Present (Exception_Handlers (gnat_node)) - && Exception_Mechanism == Front_End_SJLJ); - const bool at_end = !type_annotate_only && Present (At_End_Proc (gnat_node)); - const bool binding_for_block = (at_end || gcc_eh || fe_sjlj_eh); - tree gnu_jmpsave_decl = NULL_TREE; - tree gnu_jmpbuf_decl = NULL_TREE; - tree gnu_inner_block; /* The statement(s) for the block itself. */ - tree gnu_result; - tree gnu_expr; - Node_Id gnat_temp; - - /* The GCC exception handling mechanism can handle both ZCX and SJLJ schemes - and the front-end has its own SJLJ mechanism. To call the GCC mechanism, - we call add_cleanup, and when we leave the binding, end_stmt_group will - create the TRY_FINALLY_EXPR construct. - - ??? The region level calls down there have been specifically put in place - for a ZCX context and currently the order in which things are emitted - (region/handlers) is different from the SJLJ case. Instead of putting - other calls with different conditions at other places for the SJLJ case, - it seems cleaner to reorder things for the SJLJ case and generalize the - condition to make it not ZCX specific. - - If there are any exceptions or cleanup processing involved, we need an - outer statement group (for front-end SJLJ) and binding level. */ - if (binding_for_block) - { - start_stmt_group (); - gnat_pushlevel (); - } - - /* If using fe_sjlj_eh, make the variables for the setjmp buffer and save - area for address of previous buffer. Do this first since we need to have - the setjmp buf known for any decls in this block. */ - if (fe_sjlj_eh) - { - gnu_jmpsave_decl - = create_var_decl (get_identifier ("JMPBUF_SAVE"), NULL_TREE, - jmpbuf_ptr_type, - build_call_n_expr (get_jmpbuf_decl, 0), - false, false, false, false, false, true, false, - NULL, gnat_node); - - /* The __builtin_setjmp receivers will immediately reinstall it. Now - because of the unstructured form of EH used by fe_sjlj_eh, there - might be forward edges going to __builtin_setjmp receivers on which - it is uninitialized, although they will never be actually taken. */ - suppress_warning (gnu_jmpsave_decl, OPT_Wuninitialized); - gnu_jmpbuf_decl - = create_var_decl (get_identifier ("JMP_BUF"), NULL_TREE, - jmpbuf_type, - NULL_TREE, - false, false, false, false, false, true, false, - NULL, gnat_node); - - set_block_jmpbuf_decl (gnu_jmpbuf_decl); - - /* When we exit this block, restore the saved value. */ - add_cleanup (build_call_n_expr (set_jmpbuf_decl, 1, gnu_jmpsave_decl), - Present (End_Label (gnat_node)) - ? End_Label (gnat_node) : gnat_node); - } - - /* If we are to call a function when exiting this block, add a cleanup - to the binding level we made above. Note that add_cleanup is FIFO - so we must register this cleanup after the EH cleanup just above. */ - if (at_end) - { - tree proc_decl = gnat_to_gnu (At_End_Proc (gnat_node)); - - /* When not optimizing, disable inlining of finalizers as this can - create a more complex CFG in the parent function. */ - if (!optimize || optimize_debug) - DECL_DECLARED_INLINE_P (proc_decl) = 0; - - /* If there is no end label attached, we use the location of the At_End - procedure because Expand_Cleanup_Actions might reset the location of - the enclosing construct to that of an inner statement. */ - add_cleanup (build_call_n_expr (proc_decl, 0), - Present (End_Label (gnat_node)) - ? End_Label (gnat_node) : At_End_Proc (gnat_node)); - } - - /* Now build the tree for the declarations and statements inside this block. - If this is SJLJ, set our jmp_buf as the current buffer. */ - start_stmt_group (); - - if (fe_sjlj_eh) - { - gnu_expr = build_call_n_expr (set_jmpbuf_decl, 1, - build_unary_op (ADDR_EXPR, NULL_TREE, - gnu_jmpbuf_decl)); - set_expr_location_from_node (gnu_expr, gnat_node); - add_stmt (gnu_expr); - } - - if (Present (First_Real_Statement (gnat_node))) - process_decls (Statements (gnat_node), Empty, - First_Real_Statement (gnat_node), true, true); - - /* Generate code for each statement in the block. */ - for (gnat_temp = (Present (First_Real_Statement (gnat_node)) - ? First_Real_Statement (gnat_node) - : First (Statements (gnat_node))); - Present (gnat_temp); gnat_temp = Next (gnat_temp)) - add_stmt (gnat_to_gnu (gnat_temp)); - - gnu_inner_block = end_stmt_group (); - - /* Now generate code for the two exception models, if either is relevant for - this block. */ - if (fe_sjlj_eh) - { - tree *gnu_else_ptr = 0; - tree gnu_handler; - - /* Make a binding level for the exception handling declarations and code - and set up gnu_except_ptr_stack for the handlers to use. */ - start_stmt_group (); - gnat_pushlevel (); - - vec_safe_push (gnu_except_ptr_stack, - create_var_decl (get_identifier ("EXCEPT_PTR"), NULL_TREE, - build_pointer_type (except_type_node), - build_call_n_expr (get_excptr_decl, 0), - false, false, false, false, false, - true, false, NULL, gnat_node)); - - /* Generate code for each handler. The N_Exception_Handler case does the - real work and returns a COND_EXPR for each handler, which we chain - together here. */ - for (gnat_temp = First_Non_Pragma (Exception_Handlers (gnat_node)); - Present (gnat_temp); gnat_temp = Next_Non_Pragma (gnat_temp)) - { - gnu_expr = gnat_to_gnu (gnat_temp); - - /* If this is the first one, set it as the outer one. Otherwise, - point the "else" part of the previous handler to us. Then point - to our "else" part. */ - if (!gnu_else_ptr) - add_stmt (gnu_expr); - else - *gnu_else_ptr = gnu_expr; - - gnu_else_ptr = &COND_EXPR_ELSE (gnu_expr); - } - - /* If none of the exception handlers did anything, re-raise but do not - defer abortion. */ - gnu_expr = build_call_n_expr (raise_nodefer_decl, 1, - gnu_except_ptr_stack->last ()); - set_expr_location_from_node - (gnu_expr, - Present (End_Label (gnat_node)) ? End_Label (gnat_node) : gnat_node); - - if (gnu_else_ptr) - *gnu_else_ptr = gnu_expr; - else - add_stmt (gnu_expr); - - /* End the binding level dedicated to the exception handlers and get the - whole statement group. */ - gnu_except_ptr_stack->pop (); - gnat_poplevel (); - gnu_handler = end_stmt_group (); - - /* If the setjmp returns 1, we restore our incoming longjmp value and - then check the handlers. */ - start_stmt_group (); - add_stmt_with_node (build_call_n_expr (set_jmpbuf_decl, 1, - gnu_jmpsave_decl), - gnat_node); - add_stmt (gnu_handler); - gnu_handler = end_stmt_group (); - - /* This block is now "if (setjmp) ... <handlers> else <block>". */ - gnu_result = build3 (COND_EXPR, void_type_node, - (build_call_n_expr - (setjmp_decl, 1, - build_unary_op (ADDR_EXPR, NULL_TREE, - gnu_jmpbuf_decl))), - gnu_handler, gnu_inner_block); - } - else if (gcc_eh) - { - tree gnu_handlers; - location_t locus; - - /* First make a block containing the handlers. */ - start_stmt_group (); - for (gnat_temp = First_Non_Pragma (Exception_Handlers (gnat_node)); - Present (gnat_temp); - gnat_temp = Next_Non_Pragma (gnat_temp)) - add_stmt (gnat_to_gnu (gnat_temp)); - gnu_handlers = end_stmt_group (); - - /* Now make the TRY_CATCH_EXPR for the block. */ - gnu_result = build2 (TRY_CATCH_EXPR, void_type_node, - gnu_inner_block, gnu_handlers); - /* Set a location. We need to find a unique location for the dispatching - code, otherwise we can get coverage or debugging issues. Try with - the location of the end label. */ - if (Present (End_Label (gnat_node)) - && Sloc_to_locus (Sloc (End_Label (gnat_node)), &locus)) - SET_EXPR_LOCATION (gnu_result, locus); - else - /* Clear column information so that the exception handler of an - implicit transient block does not incorrectly inherit the slocs - of a decision, which would otherwise confuse control flow based - coverage analysis tools. */ - set_expr_location_from_node (gnu_result, gnat_node, true); - } - else - gnu_result = gnu_inner_block; - - /* Now close our outer block, if we had to make one. */ - if (binding_for_block) - { - add_stmt (gnu_result); - gnat_poplevel (); - gnu_result = end_stmt_group (); - } - - return gnu_result; -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler, - to a GCC tree, which is returned. This is the variant for front-end sjlj - exception handling. */ - -static tree -Exception_Handler_to_gnu_fe_sjlj (Node_Id gnat_node) -{ - /* Unless this is "Others" or the special "Non-Ada" exception for Ada, make - an "if" statement to select the proper exceptions. For "Others", exclude - exceptions where Handled_By_Others is nonzero unless the All_Others flag - is set. For "Non-ada", accept an exception if "Lang" is 'V'. */ - tree gnu_choice = boolean_false_node; - tree gnu_body = build_stmt_group (Statements (gnat_node), false); - Node_Id gnat_temp; - - for (gnat_temp = First (Exception_Choices (gnat_node)); - gnat_temp; gnat_temp = Next (gnat_temp)) - { - tree this_choice; - - if (Nkind (gnat_temp) == N_Others_Choice) - { - if (All_Others (gnat_temp)) - this_choice = boolean_true_node; - else - this_choice - = build_binary_op - (EQ_EXPR, boolean_type_node, - convert - (integer_type_node, - build_component_ref - (build_unary_op - (INDIRECT_REF, NULL_TREE, - gnu_except_ptr_stack->last ()), - not_handled_by_others_decl, - false)), - integer_zero_node); - } - - else if (Nkind (gnat_temp) == N_Identifier - || Nkind (gnat_temp) == N_Expanded_Name) - { - Entity_Id gnat_ex_id = Entity (gnat_temp); - tree gnu_expr; - - /* Exception may be a renaming. Recover original exception which is - the one elaborated and registered. */ - if (Present (Renamed_Object (gnat_ex_id))) - gnat_ex_id = Renamed_Object (gnat_ex_id); - - gnu_expr = gnat_to_gnu_entity (gnat_ex_id, NULL_TREE, false); - - this_choice - = build_binary_op - (EQ_EXPR, boolean_type_node, - gnu_except_ptr_stack->last (), - convert (TREE_TYPE (gnu_except_ptr_stack->last ()), - build_unary_op (ADDR_EXPR, NULL_TREE, gnu_expr))); - } - else - gcc_unreachable (); - - gnu_choice = build_binary_op (TRUTH_ORIF_EXPR, boolean_type_node, - gnu_choice, this_choice); - } - - return build3 (COND_EXPR, void_type_node, gnu_choice, gnu_body, NULL_TREE); -} - -/* Return true if no statement in GNAT_LIST can alter the control flow. */ - -static bool -stmt_list_cannot_alter_control_flow_p (List_Id gnat_list) -{ - if (No (gnat_list)) - return true; - - /* This is very conservative, we reject everything except for simple - assignments between identifiers or literals. */ - for (Node_Id gnat_node = First (gnat_list); - Present (gnat_node); - gnat_node = Next (gnat_node)) - { - if (Nkind (gnat_node) != N_Assignment_Statement) - return false; - - if (Nkind (Name (gnat_node)) != N_Identifier) - return false; - - Node_Kind nkind = Nkind (Expression (gnat_node)); - if (nkind != N_Identifier - && nkind != N_Integer_Literal - && nkind != N_Real_Literal) - return false; - } - - return true; -} - -/* Subroutine of gnat_to_gnu to translate gnat_node, an N_Exception_Handler, - to a GCC tree, which is returned. This is the variant for GCC exception - schemes. */ - -static tree -Exception_Handler_to_gnu_gcc (Node_Id gnat_node) -{ - tree gnu_etypes_list = NULL_TREE; - - /* We build a TREE_LIST of nodes representing what exception types this - handler can catch, with special cases for others and all others cases. - - Each exception type is actually identified by a pointer to the exception - id, or to a dummy object for "others" and "all others". */ - for (Node_Id gnat_temp = First (Exception_Choices (gnat_node)); - gnat_temp; - gnat_temp = Next (gnat_temp)) - { - tree gnu_expr, gnu_etype; - - if (Nkind (gnat_temp) == N_Others_Choice) - { - gnu_expr = All_Others (gnat_temp) ? all_others_decl : others_decl; - gnu_etype = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_expr); - } - else if (Nkind (gnat_temp) == N_Identifier - || Nkind (gnat_temp) == N_Expanded_Name) - { - Entity_Id gnat_ex_id = Entity (gnat_temp); - - /* Exception may be a renaming. Recover original exception which is - the one elaborated and registered. */ - if (Present (Renamed_Object (gnat_ex_id))) - gnat_ex_id = Renamed_Object (gnat_ex_id); - - gnu_expr = gnat_to_gnu_entity (gnat_ex_id, NULL_TREE, false); - gnu_etype = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_expr); - } - else - gcc_unreachable (); - - /* The GCC interface expects NULL to be passed for catch all handlers, so - it would be quite tempting to set gnu_etypes_list to NULL if gnu_etype - is integer_zero_node. It would not work, however, because GCC's - notion of "catch all" is stronger than our notion of "others". Until - we correctly use the cleanup interface as well, doing that would - prevent the "all others" handlers from being seen, because nothing - can be caught beyond a catch all from GCC's point of view. */ - gnu_etypes_list = tree_cons (NULL_TREE, gnu_etype, gnu_etypes_list); - } - - start_stmt_group (); - gnat_pushlevel (); - - /* Expand a call to the begin_handler hook at the beginning of the - handler, and arrange for a call to the end_handler hook to occur - on every possible exit path. GDB sets a breakpoint in the - begin_handler for catchpoints. - - A v1 begin handler saves the cleanup from the exception object, - and marks the exception as in use, so that it will not be - released by other handlers. A v1 end handler restores the - cleanup and releases the exception object, unless it is still - claimed, or the exception is being propagated (reraised). - - __builtin_eh_pointer references the exception occurrence being - handled or propagated. Within the handler region, it is the - former, but within the else branch of the EH_ELSE_EXPR, i.e. the - exceptional cleanup path, it is the latter, so we must save the - occurrence being handled early on, so that, should an exception - be (re)raised, we can release the current exception, or figure - out we're not to release it because we're propagating a reraise - thereof. - - We use local variables to retrieve the incoming value at handler - entry time (EXPTR), the saved cleanup (EXCLN) and the token - (EXVTK), and reuse them to feed the end_handler hook's argument - at exit. */ - - /* CODE: void *EXPTR = __builtin_eh_pointer (0); */ - tree gnu_current_exc_ptr - = build_call_expr (builtin_decl_explicit (BUILT_IN_EH_POINTER), - 1, integer_zero_node); - tree exc_ptr - = create_var_decl (get_identifier ("EXPTR"), NULL_TREE, - ptr_type_node, gnu_current_exc_ptr, - true, false, false, false, false, true, true, - NULL, gnat_node); - - tree prev_gnu_incoming_exc_ptr = gnu_incoming_exc_ptr; - gnu_incoming_exc_ptr = exc_ptr; - - /* begin_handler_decl must not throw, so we can use it as an - initializer for a variable used in cleanups. - - CODE: void *EXCLN = __gnat_begin_handler_v1 (EXPTR); */ - tree exc_cleanup - = create_var_decl (get_identifier ("EXCLN"), NULL_TREE, - ptr_type_node, - build_call_n_expr (begin_handler_decl, 1, - exc_ptr), - true, false, false, false, false, - true, true, NULL, gnat_node); - - /* Declare and initialize the choice parameter, if present. */ - if (Present (Choice_Parameter (gnat_node))) - { - tree gnu_param - = gnat_to_gnu_entity (Choice_Parameter (gnat_node), NULL_TREE, true); - - /* CODE: __gnat_set_exception_parameter (&choice_param, EXPTR); */ - add_stmt (build_call_n_expr - (set_exception_parameter_decl, 2, - build_unary_op (ADDR_EXPR, NULL_TREE, gnu_param), - gnu_incoming_exc_ptr)); - } - - /* CODE: <handler proper> */ - add_stmt_list (Statements (gnat_node)); - - tree call = build_call_n_expr (end_handler_decl, 3, - exc_ptr, - exc_cleanup, - null_pointer_node); - /* If the handler can only end by falling off the end, don't bother - with cleanups. */ - if (stmt_list_cannot_alter_control_flow_p (Statements (gnat_node))) - /* CODE: __gnat_end_handler_v1 (EXPTR, EXCLN, NULL); */ - add_stmt_with_node (call, gnat_node); - /* Otherwise, all of the above is after - CODE: try { - - The call above will appear after - CODE: } finally { - - And the code below will appear after - CODE: } else { - - The else block to a finally block is taken instead of the finally - block when an exception propagates out of the try block. */ - else - { - start_stmt_group (); - gnat_pushlevel (); - /* CODE: void *EXPRP = __builtin_eh_handler (0); */ - tree prop_ptr - = create_var_decl (get_identifier ("EXPRP"), NULL_TREE, - ptr_type_node, - build_call_expr (builtin_decl_explicit - (BUILT_IN_EH_POINTER), - 1, integer_zero_node), - true, false, false, false, false, - true, true, NULL, gnat_node); - - /* CODE: __gnat_end_handler_v1 (EXPTR, EXCLN, EXPRP); */ - tree ecall = build_call_n_expr (end_handler_decl, 3, - exc_ptr, - exc_cleanup, - prop_ptr); - - add_stmt_with_node (ecall, gnat_node); - - /* CODE: } */ - gnat_poplevel (); - tree eblk = end_stmt_group (); - tree ehls = build2 (EH_ELSE_EXPR, void_type_node, call, eblk); - add_cleanup (ehls, gnat_node); - } - - gnat_poplevel (); - - gnu_incoming_exc_ptr = prev_gnu_incoming_exc_ptr; - - return - build2 (CATCH_EXPR, void_type_node, gnu_etypes_list, end_stmt_group ()); -} - -/* Subroutine of gnat_to_gnu to generate code for an N_Compilation unit. */ - -static void -Compilation_Unit_to_gnu (Node_Id gnat_node) -{ - const Node_Id gnat_unit = Unit (gnat_node); - const bool body_p = (Nkind (gnat_unit) == N_Package_Body - || Nkind (gnat_unit) == N_Subprogram_Body); - const Entity_Id gnat_unit_entity = Defining_Entity (gnat_unit); - Entity_Id gnat_entity; - Node_Id gnat_pragma, gnat_iter; - /* Make the decl for the elaboration procedure. Emit debug info for it, so - that users can break into their elaboration code in debuggers. Kludge: - don't consider it as a definition so that we have a line map for its - body, but no subprogram description in debug info. In addition, don't - qualify it as artificial, even though it is not a user subprogram per se, - in particular for specs. Unlike, say, clones created internally by the - compiler, this subprogram materializes specific user code and flagging it - artificial would take elab code away from gcov's analysis. */ - tree gnu_elab_proc_decl - = create_subprog_decl - (create_concat_name (gnat_unit_entity, body_p ? "elabb" : "elabs"), - NULL_TREE, void_ftype, NULL_TREE, - is_default, true, false, false, true, false, NULL, gnat_unit); - struct elab_info *info; - - vec_safe_push (gnu_elab_proc_stack, gnu_elab_proc_decl); - DECL_ELABORATION_PROC_P (gnu_elab_proc_decl) = 1; - - /* Initialize the information structure for the function. */ - allocate_struct_function (gnu_elab_proc_decl, false); - set_cfun (NULL); - - current_function_decl = NULL_TREE; - - start_stmt_group (); - gnat_pushlevel (); - - /* For a body, first process the spec if there is one. */ - if (Nkind (gnat_unit) == N_Package_Body - || (Nkind (gnat_unit) == N_Subprogram_Body && !Acts_As_Spec (gnat_node))) - add_stmt (gnat_to_gnu (Library_Unit (gnat_node))); - - if (type_annotate_only && gnat_node == Cunit (Main_Unit)) - { - elaborate_all_entities (gnat_node); - - if (Nkind (gnat_unit) == N_Subprogram_Declaration - || Nkind (gnat_unit) == N_Generic_Package_Declaration - || Nkind (gnat_unit) == N_Generic_Subprogram_Declaration) - return; - } - - /* Then process any pragmas and declarations preceding the unit. */ - for (gnat_pragma = First (Context_Items (gnat_node)); - Present (gnat_pragma); - gnat_pragma = Next (gnat_pragma)) - if (Nkind (gnat_pragma) == N_Pragma) - add_stmt (gnat_to_gnu (gnat_pragma)); - process_decls (Declarations (Aux_Decls_Node (gnat_node)), Empty, Empty, - true, true); - - /* Process the unit itself. */ - add_stmt (gnat_to_gnu (gnat_unit)); - - /* Generate code for all the inlined subprograms. */ - for (gnat_entity = First_Inlined_Subprogram (gnat_node); - Present (gnat_entity); - gnat_entity = Next_Inlined_Subprogram (gnat_entity)) - { - Node_Id gnat_body; - - /* Without optimization, process only the required subprograms. */ - if (!optimize && !Has_Pragma_Inline_Always (gnat_entity)) - continue; - - /* The set of inlined subprograms is computed from data recorded early - during expansion and it can be a strict superset of the final set - computed after semantic analysis, for example if a call to such a - subprogram occurs in a pragma Assert and assertions are disabled. - In that case, semantic analysis resets Is_Public to false but the - entry for the subprogram in the inlining tables is stalled. */ - if (!Is_Public (gnat_entity)) - continue; - - gnat_body = Parent (Declaration_Node (gnat_entity)); - if (Nkind (gnat_body) != N_Subprogram_Body) - { - /* ??? This happens when only the spec of a package is provided. */ - if (No (Corresponding_Body (gnat_body))) - continue; - - gnat_body - = Parent (Declaration_Node (Corresponding_Body (gnat_body))); - } - - /* Define the entity first so we set DECL_EXTERNAL. */ - gnat_to_gnu_entity (gnat_entity, NULL_TREE, false); - add_stmt (gnat_to_gnu (gnat_body)); - } - - /* Process any pragmas and actions following the unit. */ - add_stmt_list (Pragmas_After (Aux_Decls_Node (gnat_node))); - add_stmt_list (Actions (Aux_Decls_Node (gnat_node))); - finalize_from_limited_with (); - - /* Then process the expressions of pragma Compile_Time_{Error|Warning} to - annotate types referenced therein if they have not been annotated. */ - for (int i = 0; gnat_compile_time_expr_list.iterate (i, &gnat_iter); i++) - (void) gnat_to_gnu_external (gnat_iter); - gnat_compile_time_expr_list.release (); - - /* Save away what we've made so far and finish it up. */ - set_current_block_context (gnu_elab_proc_decl); - gnat_poplevel (); - DECL_SAVED_TREE (gnu_elab_proc_decl) = end_stmt_group (); - set_end_locus_from_node (gnu_elab_proc_decl, gnat_unit); - gnu_elab_proc_stack->pop (); - - /* Record this potential elaboration procedure for later processing. */ - info = ggc_alloc<elab_info> (); - info->next = elab_info_list; - info->elab_proc = gnu_elab_proc_decl; - info->gnat_node = gnat_node; - elab_info_list = info; - - /* Force the processing for all nodes that remain in the queue. */ - process_deferred_decl_context (true); -} - -/* Mark COND, a boolean expression, as predicating a call to a noreturn - function, i.e. predict that it is very likely false, and return it. - - The compiler will automatically predict the last edge leading to a call - to a noreturn function as very unlikely taken. This function makes it - possible to extend the prediction to predecessors in case the condition - is made up of several short-circuit operators. */ - -static tree -build_noreturn_cond (tree cond) -{ - tree pred_cst = build_int_cst (integer_type_node, PRED_NORETURN); - return - build_call_expr_internal_loc (UNKNOWN_LOCATION, IFN_BUILTIN_EXPECT, - boolean_type_node, 3, cond, - boolean_false_node, pred_cst); -} - -/* Subroutine of gnat_to_gnu to translate GNAT_RANGE, a node representing a - range of values, into GNU_LOW and GNU_HIGH bounds. */ - -static void -Range_to_gnu (Node_Id gnat_range, tree *gnu_low, tree *gnu_high) -{ - /* GNAT_RANGE is either an N_Range or an identifier denoting a subtype. */ - switch (Nkind (gnat_range)) - { - case N_Range: - *gnu_low = gnat_to_gnu (Low_Bound (gnat_range)); - *gnu_high = gnat_to_gnu (High_Bound (gnat_range)); - break; - - case N_Expanded_Name: - case N_Identifier: - { - tree gnu_range_type = get_unpadded_type (Entity (gnat_range)); - tree gnu_range_base_type = get_base_type (gnu_range_type); - - *gnu_low - = convert (gnu_range_base_type, TYPE_MIN_VALUE (gnu_range_type)); - *gnu_high - = convert (gnu_range_base_type, TYPE_MAX_VALUE (gnu_range_type)); - } - break; - - default: - gcc_unreachable (); - } -} - -/* Subroutine of gnat_to_gnu to translate GNAT_NODE, an N_Raise_xxx_Error, - to a GCC tree and return it. GNU_RESULT_TYPE_P is a pointer to where - we should place the result type. */ - -static tree -Raise_Error_to_gnu (Node_Id gnat_node, tree *gnu_result_type_p) -{ - const Node_Kind kind = Nkind (gnat_node); - const Node_Id gnat_cond = Condition (gnat_node); - const int reason = UI_To_Int (Reason (gnat_node)); - const bool with_extra_info - = Exception_Extra_Info - && !No_Exception_Handlers_Set () - && No (get_exception_label (kind)); - tree gnu_result = NULL_TREE, gnu_cond = NULL_TREE; - Node_Id gnat_rcond; - - /* The following processing is not required for correctness. Its purpose is - to give more precise error messages and to record some information. */ - switch (reason) - { - case CE_Access_Check_Failed: - if (with_extra_info) - gnu_result = build_call_raise_column (reason, gnat_node, kind); - break; - - case CE_Index_Check_Failed: - case CE_Range_Check_Failed: - case CE_Invalid_Data: - if (No (gnat_cond) || Nkind (gnat_cond) != N_Op_Not) - break; - gnat_rcond = Right_Opnd (gnat_cond); - if (Nkind (gnat_rcond) == N_In - || Nkind (gnat_rcond) == N_Op_Ge - || Nkind (gnat_rcond) == N_Op_Le) - { - const Node_Id gnat_index = Left_Opnd (gnat_rcond); - const Node_Id gnat_type = Etype (gnat_index); - tree gnu_index = gnat_to_gnu (gnat_index); - tree gnu_type = get_unpadded_type (gnat_type); - tree gnu_low_bound, gnu_high_bound, disp; - struct loop_info_d *loop; - bool neg_p; - - switch (Nkind (gnat_rcond)) - { - case N_In: - Range_to_gnu (Right_Opnd (gnat_rcond), - &gnu_low_bound, &gnu_high_bound); - break; - - case N_Op_Ge: - gnu_low_bound = gnat_to_gnu (Right_Opnd (gnat_rcond)); - gnu_high_bound = TYPE_MAX_VALUE (gnu_type); - break; - - case N_Op_Le: - gnu_low_bound = TYPE_MIN_VALUE (gnu_type); - gnu_high_bound = gnat_to_gnu (Right_Opnd (gnat_rcond)); - break; - - default: - gcc_unreachable (); - } - - gnu_type = maybe_character_type (gnu_type); - if (TREE_TYPE (gnu_index) != gnu_type) - { - gnu_low_bound = convert (gnu_type, gnu_low_bound); - gnu_high_bound = convert (gnu_type, gnu_high_bound); - gnu_index = convert (gnu_type, gnu_index); - } - - if (with_extra_info - && Known_Esize (gnat_type) - && UI_To_Int (Esize (gnat_type)) <= 32) - gnu_result - = build_call_raise_range (reason, gnat_node, kind, gnu_index, - gnu_low_bound, gnu_high_bound); - - /* If optimization is enabled and we are inside a loop, we try to - compute invariant conditions for checks applied to the iteration - variable, i.e. conditions that are independent of the variable - and necessary in order for the checks to fail in the course of - some iteration. If we succeed, we consider an alternative: - - 1. If loop unswitching is enabled, we prepend these conditions - to the original conditions of the checks. This will make it - possible for the loop unswitching pass to replace the loop - with two loops, one of which has the checks eliminated and - the other has the original checks reinstated, and a prologue - implementing a run-time selection. The former loop will be - for example suitable for vectorization. - - 2. Otherwise, we instead append the conditions to the original - conditions of the checks. At worse, if the conditions cannot - be evaluated at compile time, they will be evaluated as true - at run time only when the checks have already failed, thus - contributing negatively only to the size of the executable. - But the hope is that these invariant conditions be evaluated - at compile time to false, thus taking away the entire checks - with them. */ - if (optimize - && inside_loop_p () - && (!gnu_low_bound - || (gnu_low_bound = gnat_invariant_expr (gnu_low_bound))) - && (!gnu_high_bound - || (gnu_high_bound = gnat_invariant_expr (gnu_high_bound))) - && (loop = find_loop_for (gnu_index, &disp, &neg_p))) - { - struct range_check_info_d *rci = ggc_alloc<range_check_info_d> (); - rci->low_bound = gnu_low_bound; - rci->high_bound = gnu_high_bound; - rci->disp = disp; - rci->neg_p = neg_p; - rci->type = gnu_type; - rci->inserted_cond - = build1 (SAVE_EXPR, boolean_type_node, boolean_true_node); - vec_safe_push (loop->checks, rci); - gnu_cond = build_noreturn_cond (gnat_to_gnu (gnat_cond)); - if (optimize >= 3) - gnu_cond = build_binary_op (TRUTH_ANDIF_EXPR, - boolean_type_node, - rci->inserted_cond, - gnu_cond); - else - gnu_cond = build_binary_op (TRUTH_ANDIF_EXPR, - boolean_type_node, - gnu_cond, - rci->inserted_cond); - } - } - break; - - default: - break; - } - - /* The following processing does the real work, but we must nevertheless make - sure not to override the result of the previous processing. */ - if (!gnu_result) - gnu_result = build_call_raise (reason, gnat_node, kind); - set_expr_location_from_node (gnu_result, gnat_node); - - *gnu_result_type_p = get_unpadded_type (Etype (gnat_node)); - - /* If the type is VOID, this is a statement, so we need to generate the code - for the call. Handle a condition, if there is one. */ - if (VOID_TYPE_P (*gnu_result_type_p)) - { - if (Present (gnat_cond)) - { - if (!gnu_cond) - gnu_cond = gnat_to_gnu (gnat_cond); - if (integer_zerop (gnu_cond)) - return alloc_stmt_list (); - gnu_result = build3 (COND_EXPR, void_type_node, gnu_cond, gnu_result, - alloc_stmt_list ()); - } - } - else - { - /* The condition field must not be present when the node is used as an - expression form. */ - gigi_checking_assert (No (gnat_cond)); - gnu_result = build1 (NULL_EXPR, *gnu_result_type_p, gnu_result); - } - - return gnu_result; -} - -/* Return true if GNAT_NODE is on the LHS of an assignment or an actual - parameter of a call. */ - -static bool -lhs_or_actual_p (Node_Id gnat_node) -{ - const Node_Id gnat_parent = Parent (gnat_node); - const Node_Kind kind = Nkind (gnat_parent); - - if (kind == N_Assignment_Statement && Name (gnat_parent) == gnat_node) - return true; - - if ((kind == N_Procedure_Call_Statement || kind == N_Function_Call) - && Name (gnat_parent) != gnat_node) - return true; - - if (kind == N_Parameter_Association) - return true; - - return false; -} - -/* Return true if either GNAT_NODE or a view of GNAT_NODE is on the LHS - of an assignment or an actual parameter of a call. */ - -static bool -present_in_lhs_or_actual_p (Node_Id gnat_node) -{ - if (lhs_or_actual_p (gnat_node)) - return true; - - const Node_Kind kind = Nkind (Parent (gnat_node)); - - if ((kind == N_Type_Conversion || kind == N_Unchecked_Type_Conversion) - && lhs_or_actual_p (Parent (gnat_node))) - return true; - - return false; -} - -/* Return true if GNAT_NODE, an unchecked type conversion, is a no-op as far - as gigi is concerned. This is used to avoid conversions on the LHS. */ - -static bool -unchecked_conversion_nop (Node_Id gnat_node) -{ - Entity_Id from_type, to_type; - - /* The conversion must be on the LHS of an assignment or an actual parameter - of a call. Otherwise, even if the conversion was essentially a no-op, it - could de facto ensure type consistency and this should be preserved. */ - if (!lhs_or_actual_p (gnat_node)) - return false; - - from_type = Etype (Expression (gnat_node)); - - /* We're interested in artificial conversions generated by the front-end - to make private types explicit, e.g. in Expand_Assign_Array. */ - if (!Is_Private_Type (from_type)) - return false; - - from_type = Underlying_Type (from_type); - to_type = Etype (gnat_node); - - /* The direct conversion to the underlying type is a no-op. */ - if (to_type == from_type) - return true; - - /* For an array subtype, the conversion to the PAIT is a no-op. */ - if (Ekind (from_type) == E_Array_Subtype - && to_type == Packed_Array_Impl_Type (from_type)) - return true; - - /* For a record subtype, the conversion to the type is a no-op. */ - if (Ekind (from_type) == E_Record_Subtype - && to_type == Etype (from_type)) - return true; - - return false; -} - -/* Return true if GNAT_NODE represents a statement. */ - -static bool -statement_node_p (Node_Id gnat_node) -{ - const Node_Kind kind = Nkind (gnat_node); - - if (kind == N_Label) - return true; - - if (IN (kind, N_Statement_Other_Than_Procedure_Call)) - return true; - - if (kind == N_Procedure_Call_Statement) - return true; - - if (IN (kind, N_Raise_xxx_Error) && Ekind (Etype (gnat_node)) == E_Void) - return true; - - return false; -} - -/* This function is the driver of the GNAT to GCC tree transformation process. - It is the entry point of the tree transformer. GNAT_NODE is the root of - some GNAT tree. Return the root of the corresponding GCC tree. If this - is an expression, return the GCC equivalent of the expression. If this - is a statement, return the statement or add it to the current statement - group, in which case anything returned is to be interpreted as occurring - after anything added. */ - -tree -gnat_to_gnu (Node_Id gnat_node) -{ - const Node_Kind kind = Nkind (gnat_node); - tree gnu_result = error_mark_node; /* Default to no value. */ - tree gnu_result_type = void_type_node; - tree gnu_expr, gnu_lhs, gnu_rhs; - Node_Id gnat_temp; - atomic_acces_t aa_type; - bool went_into_elab_proc; - bool aa_sync; - - /* Save node number for error message and set location information. */ - Current_Error_Node = gnat_node; - Sloc_to_locus (Sloc (gnat_node), &input_location); - - /* If we are only annotating types and this node is a statement, return - an empty statement list. */ - if (type_annotate_only && statement_node_p (gnat_node)) - return alloc_stmt_list (); - - /* If we are only annotating types and this node is a subexpression, return - a NULL_EXPR, but filter out nodes appearing in the expressions attached - to packed array implementation types. */ - if (type_annotate_only - && IN (kind, N_Subexpr) - && !(((IN (kind, N_Op) && kind != N_Op_Expon) - || kind == N_Type_Conversion) - && Is_Integer_Type (Etype (gnat_node))) - && !(kind == N_Attribute_Reference - && (Get_Attribute_Id (Attribute_Name (gnat_node)) == Attr_Length - || Get_Attribute_Id (Attribute_Name (gnat_node)) == Attr_Size) - && Is_Constrained (Etype (Prefix (gnat_node))) - && !Is_Constr_Subt_For_U_Nominal (Etype (Prefix (gnat_node)))) - && kind != N_Expanded_Name - && kind != N_Identifier - && !Compile_Time_Known_Value (gnat_node)) - return build1 (NULL_EXPR, get_unpadded_type (Etype (gnat_node)), - build_call_raise (CE_Range_Check_Failed, gnat_node, - N_Raise_Constraint_Error)); - - /* If this is a statement and we are at top level, it must be part of the - elaboration procedure, so mark us as being in that procedure. */ - if ((statement_node_p (gnat_node) - || kind == N_Handled_Sequence_Of_Statements - || kind == N_Implicit_Label_Declaration) - && !current_function_decl) - { - current_function_decl = get_elaboration_procedure (); - went_into_elab_proc = true; - } - else - went_into_elab_proc = false; - - switch (kind) - { - /********************************/ - /* Chapter 2: Lexical Elements */ - /********************************/ - - case N_Identifier: - case N_Expanded_Name: - case N_Operator_Symbol: - case N_Defining_Identifier: - case N_Defining_Operator_Symbol: - gnu_result = Identifier_to_gnu (gnat_node, &gnu_result_type); - - /* If atomic access is required on the RHS, build the atomic load. */ - if (simple_atomic_access_required_p (gnat_node, &aa_sync) - && !present_in_lhs_or_actual_p (gnat_node)) - gnu_result = build_atomic_load (gnu_result, aa_sync); - break; - - case N_Integer_Literal: - { - tree gnu_type; - - /* Get the type of the result, looking inside any padding and - justified modular types. Then get the value in that type. */ - gnu_type = gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - if (TREE_CODE (gnu_type) == RECORD_TYPE - && TYPE_JUSTIFIED_MODULAR_P (gnu_type)) - gnu_type = TREE_TYPE (TYPE_FIELDS (gnu_type)); - - gnu_result = UI_To_gnu (Intval (gnat_node), gnu_type); - - /* If the result overflows (meaning it doesn't fit in its base type), - abort, unless this is for a named number because that's not fatal. - We would like to check that the value is within the range of the - subtype, but that causes problems with subtypes whose usage will - raise Constraint_Error and also with biased representation. */ - if (TREE_OVERFLOW (gnu_result)) - { - if (Nkind (Parent (gnat_node)) == N_Number_Declaration) - gnu_result = error_mark_node; - else - gcc_unreachable (); - } - } - break; - - case N_Character_Literal: - /* If a Entity is present, it means that this was one of the - literals in a user-defined character type. In that case, - just return the value in the CONST_DECL. Otherwise, use the - character code. In that case, the base type should be an - INTEGER_TYPE, but we won't bother checking for that. */ - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - if (Present (Entity (gnat_node))) - gnu_result = DECL_INITIAL (get_gnu_tree (Entity (gnat_node))); - else - gnu_result - = build_int_cst (gnu_result_type, - UI_To_CC (Char_Literal_Value (gnat_node))); - break; - - case N_Real_Literal: - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If this is of a fixed-point type, the value we want is the value of - the corresponding integer. */ - if (Is_Fixed_Point_Type (Underlying_Type (Etype (gnat_node)))) - { - gnu_result = UI_To_gnu (Corresponding_Integer_Value (gnat_node), - gnu_result_type); - gcc_assert (!TREE_OVERFLOW (gnu_result)); - } - - else - { - Ureal ur_realval = Realval (gnat_node); - - /* First convert the value to a machine number if it isn't already. - That will force the base to 2 for non-zero values and simplify - the rest of the logic. */ - if (!Is_Machine_Number (gnat_node)) - ur_realval - = Machine (Base_Type (Underlying_Type (Etype (gnat_node))), - ur_realval, Round_Even, gnat_node); - - if (UR_Is_Zero (ur_realval)) - gnu_result = build_real (gnu_result_type, dconst0); - else - { - REAL_VALUE_TYPE tmp; - - gnu_result = UI_To_gnu (Numerator (ur_realval), gnu_result_type); - - /* The base must be 2 as Machine guarantees this, so we scale - the value, which we know can fit in the mantissa of the type - (hence the use of that type above). */ - gcc_assert (Rbase (ur_realval) == 2); - real_ldexp (&tmp, &TREE_REAL_CST (gnu_result), - - UI_To_Int (Denominator (ur_realval))); - gnu_result = build_real (gnu_result_type, tmp); - } - - /* Now see if we need to negate the result. Do it this way to - properly handle -0. */ - if (UR_Is_Negative (Realval (gnat_node))) - gnu_result - = build_unary_op (NEGATE_EXPR, get_base_type (gnu_result_type), - gnu_result); - } - - break; - - case N_String_Literal: - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - if (TYPE_PRECISION (TREE_TYPE (gnu_result_type)) == HOST_BITS_PER_CHAR) - { - String_Id gnat_string = Strval (gnat_node); - int length = String_Length (gnat_string); - int i; - char *string; - if (length >= ALLOCA_THRESHOLD) - string = XNEWVEC (char, length); - else - string = (char *) alloca (length); - - /* Build the string with the characters in the literal. Note - that Ada strings are 1-origin. */ - for (i = 0; i < length; i++) - string[i] = Get_String_Char (gnat_string, i + 1); - - gnu_result = build_string (length, string); - - /* Strings in GCC don't normally have types, but we want - this to not be converted to the array type. */ - TREE_TYPE (gnu_result) = gnu_result_type; - - if (length >= ALLOCA_THRESHOLD) - free (string); - } - else - { - /* Build a list consisting of each character, then make - the aggregate. */ - String_Id gnat_string = Strval (gnat_node); - int length = String_Length (gnat_string); - int i; - tree gnu_idx = TYPE_MIN_VALUE (TYPE_DOMAIN (gnu_result_type)); - tree gnu_one_node = convert (TREE_TYPE (gnu_idx), integer_one_node); - vec<constructor_elt, va_gc> *gnu_vec; - vec_alloc (gnu_vec, length); - - for (i = 0; i < length; i++) - { - tree t = build_int_cst (TREE_TYPE (gnu_result_type), - Get_String_Char (gnat_string, i + 1)); - - CONSTRUCTOR_APPEND_ELT (gnu_vec, gnu_idx, t); - gnu_idx = int_const_binop (PLUS_EXPR, gnu_idx, gnu_one_node); - } - - gnu_result = gnat_build_constructor (gnu_result_type, gnu_vec); - } - break; - - case N_Pragma: - gnu_result = Pragma_to_gnu (gnat_node); - break; - - /**************************************/ - /* Chapter 3: Declarations and Types */ - /**************************************/ - - case N_Subtype_Declaration: - case N_Full_Type_Declaration: - case N_Incomplete_Type_Declaration: - case N_Private_Type_Declaration: - case N_Private_Extension_Declaration: - case N_Task_Type_Declaration: - process_type (Defining_Entity (gnat_node)); - gnu_result = alloc_stmt_list (); - break; - - case N_Object_Declaration: - case N_Number_Declaration: - case N_Exception_Declaration: - gnat_temp = Defining_Entity (gnat_node); - gnu_result = alloc_stmt_list (); - - /* If we are just annotating types and this object has an unconstrained - or task type, don't elaborate it. */ - if (type_annotate_only - && (((Is_Array_Type (Etype (gnat_temp)) - || Is_Record_Type (Etype (gnat_temp))) - && !Is_Constrained (Etype (gnat_temp))) - || Is_Concurrent_Type (Etype (gnat_temp)))) - break; - - if (Present (Expression (gnat_node)) - && !(kind == N_Object_Declaration && No_Initialization (gnat_node)) - && (!type_annotate_only - || Compile_Time_Known_Value (Expression (gnat_node)))) - { - gigi_checking_assert (!Do_Range_Check (Expression (gnat_node))); - - gnu_expr = gnat_to_gnu (Expression (gnat_node)); - - /* First deal with erroneous expressions. */ - if (TREE_CODE (gnu_expr) == ERROR_MARK) - { - /* If this is a named number for which we cannot manipulate - the value, just skip the declaration altogether. */ - if (kind == N_Number_Declaration) - break; - else if (type_annotate_only) - gnu_expr = NULL_TREE; - } - - /* Then a special case: we do not want the SLOC of the expression - of the tag to pop up every time it is referenced somewhere. */ - else if (EXPR_P (gnu_expr) && Is_Tag (gnat_temp)) - SET_EXPR_LOCATION (gnu_expr, UNKNOWN_LOCATION); - } - else - gnu_expr = NULL_TREE; - - /* If this is a deferred constant with an address clause, we ignore the - full view since the clause is on the partial view and we cannot have - 2 different GCC trees for the object. The only bits of the full view - we will use is the initializer, but it will be directly fetched. */ - if (Ekind (gnat_temp) == E_Constant - && Present (Address_Clause (gnat_temp)) - && Present (Full_View (gnat_temp))) - save_gnu_tree (Full_View (gnat_temp), error_mark_node, true); - - /* If this object has its elaboration delayed, we must force evaluation - of GNU_EXPR now and save it for the freeze point. Note that we need - not do anything special at the global level since the lifetime of the - temporary is fully contained within the elaboration routine. */ - if (Present (Freeze_Node (gnat_temp))) - { - if (gnu_expr) - { - gnu_result = gnat_save_expr (gnu_expr); - save_gnu_tree (gnat_node, gnu_result, true); - } - } - else - gnat_to_gnu_entity (gnat_temp, gnu_expr, true); - break; - - case N_Object_Renaming_Declaration: - gnat_temp = Defining_Entity (gnat_node); - gnu_result = alloc_stmt_list (); - - /* Don't do anything if this renaming is handled by the front end and it - does not need debug info. Note that we consider renamings don't need - debug info when optimizing: our way to describe them has a - memory/elaboration footprint. - - Don't do anything neither if we are just annotating types and this - object has a composite or task type, don't elaborate it. */ - if ((!Is_Renaming_Of_Object (gnat_temp) - || (Needs_Debug_Info (gnat_temp) - && !optimize - && can_materialize_object_renaming_p - (Renamed_Object (gnat_temp)))) - && ! (type_annotate_only - && (Is_Array_Type (Etype (gnat_temp)) - || Is_Record_Type (Etype (gnat_temp)) - || Is_Concurrent_Type (Etype (gnat_temp))))) - gnat_to_gnu_entity (gnat_temp, - gnat_to_gnu (Renamed_Object (gnat_temp)), - true); - break; - - case N_Exception_Renaming_Declaration: - gnat_temp = Defining_Entity (gnat_node); - gnu_result = alloc_stmt_list (); - - if (Present (Renamed_Entity (gnat_temp))) - gnat_to_gnu_entity (gnat_temp, - gnat_to_gnu (Renamed_Entity (gnat_temp)), - true); - break; - - case N_Subprogram_Renaming_Declaration: - { - const Node_Id gnat_renaming = Defining_Entity (gnat_node); - const Node_Id gnat_renamed = Renamed_Entity (gnat_renaming); - - gnu_result = alloc_stmt_list (); - - /* Materializing renamed subprograms will only benefit the debugging - information as they aren't referenced in the generated code. So - skip them when they aren't needed. Avoid doing this if: - - - there is a freeze node: in this case the renamed entity is not - elaborated yet, - - the renamed subprogram is intrinsic: it will not be available in - the debugging information (note that both or only one of the - renaming and the renamed subprograms can be intrinsic). */ - if (!type_annotate_only - && Needs_Debug_Info (gnat_renaming) - && No (Freeze_Node (gnat_renaming)) - && Present (gnat_renamed) - && (Ekind (gnat_renamed) == E_Function - || Ekind (gnat_renamed) == E_Procedure) - && !Is_Intrinsic_Subprogram (gnat_renaming) - && !Is_Intrinsic_Subprogram (gnat_renamed)) - gnat_to_gnu_entity (gnat_renaming, gnat_to_gnu (gnat_renamed), true); - break; - } - - case N_Implicit_Label_Declaration: - gnat_to_gnu_entity (Defining_Entity (gnat_node), NULL_TREE, true); - gnu_result = alloc_stmt_list (); - break; - - case N_Package_Renaming_Declaration: - /* These are fully handled in the front end. */ - /* ??? For package renamings, find a way to use GENERIC namespaces so - that we get proper debug information for them. */ - gnu_result = alloc_stmt_list (); - break; - - /*************************************/ - /* Chapter 4: Names and Expressions */ - /*************************************/ - - case N_Explicit_Dereference: - /* Make sure the designated type is complete before dereferencing. */ - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result = gnat_to_gnu (Prefix (gnat_node)); - gnu_result = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_result); - - /* If atomic access is required on the RHS, build the atomic load. */ - if (simple_atomic_access_required_p (gnat_node, &aa_sync) - && !present_in_lhs_or_actual_p (gnat_node)) - gnu_result = build_atomic_load (gnu_result, aa_sync); - break; - - case N_Indexed_Component: - { - tree gnu_array_object = gnat_to_gnu ((Prefix (gnat_node))); - tree gnu_type; - int ndim, i; - Node_Id *gnat_expr_array; - - gnu_array_object = maybe_padded_object (gnu_array_object); - gnu_array_object = maybe_unconstrained_array (gnu_array_object); - - /* Convert vector inputs to their representative array type, to fit - what the code below expects. */ - if (VECTOR_TYPE_P (TREE_TYPE (gnu_array_object))) - { - if (present_in_lhs_or_actual_p (gnat_node)) - gnat_mark_addressable (gnu_array_object); - gnu_array_object = maybe_vector_array (gnu_array_object); - } - - /* The failure of this assertion will very likely come from a missing - expansion for a packed array access. */ - gcc_assert (TREE_CODE (TREE_TYPE (gnu_array_object)) == ARRAY_TYPE); - - /* First compute the number of dimensions of the array, then - fill the expression array, the order depending on whether - this is a Convention_Fortran array or not. */ - for (ndim = 1, gnu_type = TREE_TYPE (gnu_array_object); - TREE_CODE (TREE_TYPE (gnu_type)) == ARRAY_TYPE - && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_type)); - ndim++, gnu_type = TREE_TYPE (gnu_type)) - ; - - gnat_expr_array = XALLOCAVEC (Node_Id, ndim); - - if (TYPE_CONVENTION_FORTRAN_P (TREE_TYPE (gnu_array_object))) - for (i = ndim - 1, gnat_temp = First (Expressions (gnat_node)); - i >= 0; - i--, gnat_temp = Next (gnat_temp)) - gnat_expr_array[i] = gnat_temp; - else - for (i = 0, gnat_temp = First (Expressions (gnat_node)); - i < ndim; - i++, gnat_temp = Next (gnat_temp)) - gnat_expr_array[i] = gnat_temp; - - /* Start with the prefix and build the successive references. */ - gnu_result = gnu_array_object; - - for (i = 0, gnu_type = TREE_TYPE (gnu_array_object); - i < ndim; - i++, gnu_type = TREE_TYPE (gnu_type)) - { - gcc_assert (TREE_CODE (gnu_type) == ARRAY_TYPE); - gnat_temp = gnat_expr_array[i]; - gnu_expr = maybe_character_value (gnat_to_gnu (gnat_temp)); - - gnu_result - = build_binary_op (ARRAY_REF, NULL_TREE, gnu_result, gnu_expr); - } - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If atomic access is required on the RHS, build the atomic load. */ - if (simple_atomic_access_required_p (gnat_node, &aa_sync) - && !present_in_lhs_or_actual_p (gnat_node)) - gnu_result = build_atomic_load (gnu_result, aa_sync); - } - break; - - case N_Slice: - { - tree gnu_array_object = gnat_to_gnu (Prefix (gnat_node)); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - gnu_array_object = maybe_padded_object (gnu_array_object); - gnu_array_object = maybe_unconstrained_array (gnu_array_object); - - gnu_expr = TYPE_MIN_VALUE (TYPE_DOMAIN (gnu_result_type)); - gnu_expr = maybe_character_value (gnu_expr); - - /* If this is a slice with non-constant size of an array with constant - size, set the maximum size for the allocation of temporaries. */ - if (!TREE_CONSTANT (TYPE_SIZE_UNIT (gnu_result_type)) - && TREE_CONSTANT (TYPE_SIZE_UNIT (TREE_TYPE (gnu_array_object)))) - TYPE_ARRAY_MAX_SIZE (gnu_result_type) - = TYPE_SIZE_UNIT (TREE_TYPE (gnu_array_object)); - - gnu_result = build_binary_op (ARRAY_RANGE_REF, gnu_result_type, - gnu_array_object, gnu_expr); - } - break; - - case N_Selected_Component: - { - const Entity_Id gnat_prefix = Prefix (gnat_node); - Entity_Id gnat_field = Entity (Selector_Name (gnat_node)); - tree gnu_prefix = gnat_to_gnu (gnat_prefix); - - gnu_prefix = maybe_padded_object (gnu_prefix); - - /* gnat_to_gnu_entity does not save the GNU tree made for renamed - discriminants so avoid making recursive calls on each reference - to them by following the appropriate link directly here. */ - if (Ekind (gnat_field) == E_Discriminant) - { - /* For discriminant references in tagged types always substitute - the corresponding discriminant as the actual component. */ - if (Is_Tagged_Type (Underlying_Type (Etype (gnat_prefix)))) - while (Present (Corresponding_Discriminant (gnat_field))) - gnat_field = Corresponding_Discriminant (gnat_field); - - /* For discriminant references in untagged types always substitute - the corresponding stored discriminant. */ - else if (Present (Corresponding_Discriminant (gnat_field))) - gnat_field = Original_Record_Component (gnat_field); - } - - /* Handle extracting the real or imaginary part of a complex. - The real part is the first field and the imaginary the last. */ - if (TREE_CODE (TREE_TYPE (gnu_prefix)) == COMPLEX_TYPE) - gnu_result = build_unary_op (Present (Next_Entity (gnat_field)) - ? REALPART_EXPR : IMAGPART_EXPR, - NULL_TREE, gnu_prefix); - else - { - tree gnu_field = gnat_to_gnu_field_decl (gnat_field); - tree gnu_offset; - struct loop_info_d *loop; - - gnu_result - = build_component_ref (gnu_prefix, gnu_field, - (Nkind (Parent (gnat_node)) - == N_Attribute_Reference) - && lvalue_required_for_attribute_p - (Parent (gnat_node))); - - /* If optimization is enabled and we are inside a loop, we try to - hoist nonconstant but invariant offset computations outside of - the loop, since they very likely contain loads that could turn - out to be hard to move if they end up in active EH regions. */ - if (optimize - && inside_loop_p () - && TREE_CODE (gnu_result) == COMPONENT_REF - && (gnu_offset = component_ref_field_offset (gnu_result)) - && !TREE_CONSTANT (gnu_offset) - && (gnu_offset = gnat_invariant_expr (gnu_offset)) - && (loop = find_loop ())) - { - tree invariant - = build1 (SAVE_EXPR, TREE_TYPE (gnu_offset), gnu_offset); - vec_safe_push (loop->invariants, invariant); - tree field = TREE_OPERAND (gnu_result, 1); - tree factor - = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT); - /* Divide the offset by its alignment. */ - TREE_OPERAND (gnu_result, 2) - = size_binop (EXACT_DIV_EXPR, invariant, factor); - } - } - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If atomic access is required on the RHS, build the atomic load. */ - if (simple_atomic_access_required_p (gnat_node, &aa_sync) - && !present_in_lhs_or_actual_p (gnat_node)) - gnu_result = build_atomic_load (gnu_result, aa_sync); - } - break; - - case N_Attribute_Reference: - { - /* The attribute designator. */ - const int attr = Get_Attribute_Id (Attribute_Name (gnat_node)); - - /* The Elab_Spec and Elab_Body attributes are special in that Prefix - is a unit, not an object with a GCC equivalent. */ - if (attr == Attr_Elab_Spec || attr == Attr_Elab_Body) - return - create_subprog_decl (create_concat_name - (Entity (Prefix (gnat_node)), - attr == Attr_Elab_Body ? "elabb" : "elabs"), - NULL_TREE, void_ftype, NULL_TREE, is_default, - true, true, true, true, false, NULL, - gnat_node); - - gnu_result = Attribute_to_gnu (gnat_node, &gnu_result_type, attr); - } - break; - - case N_Reference: - /* Like 'Access as far as we are concerned. */ - gnu_result = gnat_to_gnu (Prefix (gnat_node)); - gnu_result = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_result); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - break; - - case N_Aggregate: - case N_Extension_Aggregate: - { - tree gnu_aggr_type; - - /* Check that this aggregate has not slipped through the cracks. */ - gcc_assert (!Expansion_Delayed (gnat_node)); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - if (TREE_CODE (gnu_result_type) == RECORD_TYPE - && TYPE_CONTAINS_TEMPLATE_P (gnu_result_type)) - gnu_aggr_type - = TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (gnu_result_type))); - else if (TREE_CODE (gnu_result_type) == VECTOR_TYPE) - gnu_aggr_type = TYPE_REPRESENTATIVE_ARRAY (gnu_result_type); - else - gnu_aggr_type = gnu_result_type; - - if (Null_Record_Present (gnat_node)) - gnu_result = gnat_build_constructor (gnu_aggr_type, NULL); - - else if (TREE_CODE (gnu_aggr_type) == RECORD_TYPE - || TREE_CODE (gnu_aggr_type) == UNION_TYPE) - gnu_result - = assoc_to_constructor (Etype (gnat_node), - First (Component_Associations (gnat_node)), - gnu_aggr_type); - else if (TREE_CODE (gnu_aggr_type) == ARRAY_TYPE) - gnu_result = pos_to_constructor (First (Expressions (gnat_node)), - gnu_aggr_type); - else if (TREE_CODE (gnu_aggr_type) == COMPLEX_TYPE) - gnu_result - = build_binary_op - (COMPLEX_EXPR, gnu_aggr_type, - gnat_to_gnu (Expression (First - (Component_Associations (gnat_node)))), - gnat_to_gnu (Expression - (Next - (First (Component_Associations (gnat_node)))))); - else - gcc_unreachable (); - - gnu_result = convert (gnu_result_type, gnu_result); - } - break; - - case N_Null: - if (TARGET_VTABLE_USES_DESCRIPTORS - && Ekind (Etype (gnat_node)) == E_Access_Subprogram_Type - && Is_Dispatch_Table_Entity (Etype (gnat_node))) - gnu_result = null_fdesc_node; - else - gnu_result = null_pointer_node; - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - break; - - case N_Type_Conversion: - case N_Qualified_Expression: - gnu_expr = maybe_character_value (gnat_to_gnu (Expression (gnat_node))); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If this is a qualified expression for a tagged type, we mark the type - as used. Because of polymorphism, this might be the only reference to - the tagged type in the program while objects have it as dynamic type. - The debugger needs to see it to display these objects properly. */ - if (kind == N_Qualified_Expression && Is_Tagged_Type (Etype (gnat_node))) - used_types_insert (gnu_result_type); - - gigi_checking_assert (!Do_Range_Check (Expression (gnat_node))); - - gnu_result - = convert_with_check (Etype (gnat_node), gnu_expr, - Do_Overflow_Check (gnat_node), - kind == N_Type_Conversion - && Float_Truncate (gnat_node), gnat_node); - break; - - case N_Unchecked_Type_Conversion: - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_expr = maybe_character_value (gnat_to_gnu (Expression (gnat_node))); - - /* Skip further processing if the conversion is deemed a no-op. */ - if (unchecked_conversion_nop (gnat_node)) - { - gnu_result = gnu_expr; - gnu_result_type = TREE_TYPE (gnu_result); - break; - } - - /* If the result is a pointer type, see if we are improperly - converting to a stricter alignment. */ - if (STRICT_ALIGNMENT && POINTER_TYPE_P (gnu_result_type) - && Is_Access_Type (Etype (gnat_node))) - { - unsigned int align = known_alignment (gnu_expr); - tree gnu_obj_type = TREE_TYPE (gnu_result_type); - unsigned int oalign = TYPE_ALIGN (gnu_obj_type); - - if (align != 0 && align < oalign && !TYPE_ALIGN_OK (gnu_obj_type)) - post_error_ne_tree_2 - ("??source alignment (^) '< alignment of & (^)", - gnat_node, Designated_Type (Etype (gnat_node)), - size_int (align / BITS_PER_UNIT), oalign / BITS_PER_UNIT); - } - - /* If we are converting a descriptor to a function pointer, first - build the pointer. */ - if (TARGET_VTABLE_USES_DESCRIPTORS - && TREE_TYPE (gnu_expr) == fdesc_type_node - && POINTER_TYPE_P (gnu_result_type)) - gnu_expr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_expr); - - gnu_result = unchecked_convert (gnu_result_type, gnu_expr, - No_Truncation (gnat_node)); - break; - - case N_In: - case N_Not_In: - { - tree gnu_obj = gnat_to_gnu (Left_Opnd (gnat_node)); - tree gnu_low, gnu_high; - - Range_to_gnu (Right_Opnd (gnat_node), &gnu_low, &gnu_high); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - tree gnu_op_type = maybe_character_type (TREE_TYPE (gnu_obj)); - if (TREE_TYPE (gnu_obj) != gnu_op_type) - { - gnu_obj = convert (gnu_op_type, gnu_obj); - gnu_low = convert (gnu_op_type, gnu_low); - gnu_high = convert (gnu_op_type, gnu_high); - } - - /* If LOW and HIGH are identical, perform an equality test. Otherwise, - ensure that GNU_OBJ is evaluated only once and perform a full range - test. */ - if (operand_equal_p (gnu_low, gnu_high, 0)) - gnu_result - = build_binary_op (EQ_EXPR, gnu_result_type, gnu_obj, gnu_low); - else - { - tree t1, t2; - gnu_obj = gnat_protect_expr (gnu_obj); - t1 = build_binary_op (GE_EXPR, gnu_result_type, gnu_obj, gnu_low); - if (EXPR_P (t1)) - set_expr_location_from_node (t1, gnat_node); - t2 = build_binary_op (LE_EXPR, gnu_result_type, gnu_obj, gnu_high); - if (EXPR_P (t2)) - set_expr_location_from_node (t2, gnat_node); - gnu_result - = build_binary_op (TRUTH_ANDIF_EXPR, gnu_result_type, t1, t2); - } - - if (kind == N_Not_In) - gnu_result - = invert_truthvalue_loc (EXPR_LOCATION (gnu_result), gnu_result); - } - break; - - case N_Op_Divide: - gnu_lhs = gnat_to_gnu (Left_Opnd (gnat_node)); - gnu_rhs = gnat_to_gnu (Right_Opnd (gnat_node)); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result = build_binary_op (FLOAT_TYPE_P (gnu_result_type) - ? RDIV_EXPR - : (Rounded_Result (gnat_node) - ? ROUND_DIV_EXPR : TRUNC_DIV_EXPR), - gnu_result_type, gnu_lhs, gnu_rhs); - break; - - case N_Op_Eq: - case N_Op_Ne: - case N_Op_Lt: - case N_Op_Le: - case N_Op_Gt: - case N_Op_Ge: - case N_Op_Add: - case N_Op_Subtract: - case N_Op_Multiply: - case N_Op_Mod: - case N_Op_Rem: - case N_Op_Rotate_Left: - case N_Op_Rotate_Right: - case N_Op_Shift_Left: - case N_Op_Shift_Right: - case N_Op_Shift_Right_Arithmetic: - case N_Op_And: - case N_Op_Or: - case N_Op_Xor: - case N_And_Then: - case N_Or_Else: - { - enum tree_code code = gnu_codes[kind]; - bool ignore_lhs_overflow = false; - location_t saved_location = input_location; - tree gnu_type, gnu_max_shift = NULL_TREE; - - /* Fix operations set up for boolean types in GNU_CODES above. */ - if (Is_Modular_Integer_Type (Underlying_Type (Etype (gnat_node)))) - switch (kind) - { - case N_Op_And: - code = BIT_AND_EXPR; - break; - case N_Op_Or: - code = BIT_IOR_EXPR; - break; - case N_Op_Xor: - code = BIT_XOR_EXPR; - break; - default: - break; - } - - gnu_lhs = gnat_to_gnu (Left_Opnd (gnat_node)); - gnu_rhs = gnat_to_gnu (Right_Opnd (gnat_node)); - gnu_type = gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* If this is a shift, take the count as unsigned since that is what - most machines do and will generate simpler adjustments below. */ - if (IN (kind, N_Op_Shift)) - { - tree gnu_count_type - = gnat_unsigned_type_for (get_base_type (TREE_TYPE (gnu_rhs))); - gnu_rhs = convert (gnu_count_type, gnu_rhs); - gnu_max_shift - = convert (TREE_TYPE (gnu_rhs), TYPE_SIZE (gnu_type)); - } - - /* Pending generic support for efficient vector logical operations in - GCC, convert vectors to their representative array type view and - fallthrough. */ - gnu_lhs = maybe_vector_array (gnu_lhs); - gnu_rhs = maybe_vector_array (gnu_rhs); - - /* If this is a comparison operator, convert any references to an - unconstrained array value into a reference to the actual array. */ - if (TREE_CODE_CLASS (code) == tcc_comparison) - { - gnu_lhs = maybe_unconstrained_array (gnu_lhs); - gnu_rhs = maybe_unconstrained_array (gnu_rhs); - - tree gnu_op_type = maybe_character_type (TREE_TYPE (gnu_lhs)); - if (TREE_TYPE (gnu_lhs) != gnu_op_type) - { - gnu_lhs = convert (gnu_op_type, gnu_lhs); - gnu_rhs = convert (gnu_op_type, gnu_rhs); - } - } - - /* If this is a shift whose count is not guaranteed to be correct, - we need to adjust the shift count. */ - if ((kind == N_Op_Rotate_Left || kind == N_Op_Rotate_Right) - && !Shift_Count_OK (gnat_node)) - gnu_rhs = build_binary_op (TRUNC_MOD_EXPR, TREE_TYPE (gnu_rhs), - gnu_rhs, gnu_max_shift); - else if (kind == N_Op_Shift_Right_Arithmetic - && !Shift_Count_OK (gnat_node)) - gnu_rhs - = build_binary_op (MIN_EXPR, TREE_TYPE (gnu_rhs), - build_binary_op (MINUS_EXPR, - TREE_TYPE (gnu_rhs), - gnu_max_shift, - build_int_cst - (TREE_TYPE (gnu_rhs), 1)), - gnu_rhs); - - /* For right shifts, the type says what kind of shift to do, - so we may need to choose a different type. In this case, - we have to ignore integer overflow lest it propagates all - the way down and causes a CE to be explicitly raised. */ - if (kind == N_Op_Shift_Right && !TYPE_UNSIGNED (gnu_type)) - { - gnu_type = gnat_unsigned_type_for (gnu_type); - ignore_lhs_overflow = true; - } - else if (kind == N_Op_Shift_Right_Arithmetic - && TYPE_UNSIGNED (gnu_type)) - { - gnu_type = gnat_signed_type_for (gnu_type); - ignore_lhs_overflow = true; - } - - if (gnu_type != gnu_result_type) - { - tree gnu_old_lhs = gnu_lhs; - gnu_lhs = convert (gnu_type, gnu_lhs); - if (TREE_CODE (gnu_lhs) == INTEGER_CST && ignore_lhs_overflow) - TREE_OVERFLOW (gnu_lhs) = TREE_OVERFLOW (gnu_old_lhs); - gnu_rhs = convert (gnu_type, gnu_rhs); - if (gnu_max_shift) - gnu_max_shift = convert (gnu_type, gnu_max_shift); - } - - /* For signed integer addition, subtraction and multiplication, do an - overflow check if required. */ - if (Do_Overflow_Check (gnat_node) - && (code == PLUS_EXPR || code == MINUS_EXPR || code == MULT_EXPR) - && !TYPE_UNSIGNED (gnu_type) - && !FLOAT_TYPE_P (gnu_type)) - gnu_result - = build_binary_op_trapv (code, gnu_type, gnu_lhs, gnu_rhs, - gnat_node); - else - { - /* Some operations, e.g. comparisons of arrays, generate complex - trees that need to be annotated while they are being built. */ - input_location = saved_location; - gnu_result = build_binary_op (code, gnu_type, gnu_lhs, gnu_rhs); - } - - /* If this is a logical shift with the shift count not verified, - we must return zero if it is too large. We cannot compensate - beforehand in this case. */ - if ((kind == N_Op_Shift_Left || kind == N_Op_Shift_Right) - && !Shift_Count_OK (gnat_node)) - gnu_result - = build_cond_expr (gnu_type, - build_binary_op (GE_EXPR, boolean_type_node, - gnu_rhs, gnu_max_shift), - build_int_cst (gnu_type, 0), - gnu_result); - } - break; - - case N_If_Expression: - { - tree gnu_cond = gnat_to_gnu (First (Expressions (gnat_node))); - tree gnu_true = gnat_to_gnu (Next (First (Expressions (gnat_node)))); - tree gnu_false - = gnat_to_gnu (Next (Next (First (Expressions (gnat_node))))); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result - = build_cond_expr (gnu_result_type, gnu_cond, gnu_true, gnu_false); - } - break; - - case N_Op_Plus: - gnu_result = gnat_to_gnu (Right_Opnd (gnat_node)); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - break; - - case N_Op_Not: - /* This case can apply to a boolean or a modular type. - Fall through for a boolean operand since GNU_CODES is set - up to handle this. */ - if (Is_Modular_Integer_Type (Underlying_Type (Etype (gnat_node)))) - { - gnu_expr = gnat_to_gnu (Right_Opnd (gnat_node)); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - gnu_result = build_unary_op (BIT_NOT_EXPR, gnu_result_type, - gnu_expr); - break; - } - - /* ... fall through ... */ - - case N_Op_Minus: - case N_Op_Abs: - gnu_expr = gnat_to_gnu (Right_Opnd (gnat_node)); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - - /* For signed integer negation and absolute value, do an overflow check - if required. */ - if (Do_Overflow_Check (gnat_node) - && !TYPE_UNSIGNED (gnu_result_type) - && !FLOAT_TYPE_P (gnu_result_type)) - gnu_result - = build_unary_op_trapv (gnu_codes[kind], gnu_result_type, gnu_expr, - gnat_node); - else - gnu_result - = build_unary_op (gnu_codes[kind], gnu_result_type, gnu_expr); - break; - - case N_Allocator: - { - tree gnu_type, gnu_init; - bool ignore_init_type; - - gnat_temp = Expression (gnat_node); - - /* The expression can be either an N_Identifier or an Expanded_Name, - which must represent a type, or a N_Qualified_Expression, which - contains both the type and an initial value for the object. */ - if (Nkind (gnat_temp) == N_Identifier - || Nkind (gnat_temp) == N_Expanded_Name) - { - ignore_init_type = false; - gnu_init = NULL_TREE; - gnu_type = gnat_to_gnu_type (Entity (gnat_temp)); - } - - else if (Nkind (gnat_temp) == N_Qualified_Expression) - { - const Entity_Id gnat_desig_type - = Designated_Type (Underlying_Type (Etype (gnat_node))); - - ignore_init_type = Has_Constrained_Partial_View (gnat_desig_type); - - gnu_init = gnat_to_gnu (Expression (gnat_temp)); - gnu_init = maybe_unconstrained_array (gnu_init); - - gigi_checking_assert (!Do_Range_Check (Expression (gnat_temp))); - - if (Is_Elementary_Type (gnat_desig_type) - || Is_Constrained (gnat_desig_type)) - gnu_type = gnat_to_gnu_type (gnat_desig_type); - else - { - gnu_type = gnat_to_gnu_type (Etype (Expression (gnat_temp))); - if (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE) - gnu_type = TREE_TYPE (gnu_init); - } - - /* See the N_Qualified_Expression case for the rationale. */ - if (Is_Tagged_Type (gnat_desig_type)) - used_types_insert (gnu_type); - - gnu_init = convert (gnu_type, gnu_init); - } - else - gcc_unreachable (); - - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - return build_allocator (gnu_type, gnu_init, gnu_result_type, - Procedure_To_Call (gnat_node), - Storage_Pool (gnat_node), gnat_node, - ignore_init_type); - } - break; - - /**************************/ - /* Chapter 5: Statements */ - /**************************/ - - case N_Label: - gnu_result = build1 (LABEL_EXPR, void_type_node, - gnat_to_gnu (Identifier (gnat_node))); - break; - - case N_Null_Statement: - /* When not optimizing, turn null statements from source into gotos to - the next statement that the middle-end knows how to preserve. */ - if (!optimize && Comes_From_Source (gnat_node)) - { - tree stmt, label = create_label_decl (NULL_TREE, gnat_node); - DECL_IGNORED_P (label) = 1; - start_stmt_group (); - stmt = build1 (GOTO_EXPR, void_type_node, label); - set_expr_location_from_node (stmt, gnat_node); - add_stmt (stmt); - stmt = build1 (LABEL_EXPR, void_type_node, label); - set_expr_location_from_node (stmt, gnat_node); - add_stmt (stmt); - gnu_result = end_stmt_group (); - } - else - gnu_result = alloc_stmt_list (); - break; - - case N_Assignment_Statement: - /* Get the LHS and RHS of the statement and convert any reference to an - unconstrained array into a reference to the underlying array. */ - gnu_lhs = maybe_unconstrained_array (gnat_to_gnu (Name (gnat_node))); - - /* If the type has a size that overflows, convert this into raise of - Storage_Error: execution shouldn't have gotten here anyway. */ - if (TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (gnu_lhs))) == INTEGER_CST - && !valid_constant_size_p (TYPE_SIZE_UNIT (TREE_TYPE (gnu_lhs)))) - gnu_result = build_call_raise (SE_Object_Too_Large, gnat_node, - N_Raise_Storage_Error); - else if (Nkind (Expression (gnat_node)) == N_Function_Call) - { - get_atomic_access (Name (gnat_node), &aa_type, &aa_sync); - gnu_result - = Call_to_gnu (Expression (gnat_node), &gnu_result_type, gnu_lhs, - aa_type, aa_sync); - } - else - { - const Node_Id gnat_expr = Expression (gnat_node); - const Node_Id gnat_inner - = Nkind (gnat_expr) == N_Qualified_Expression - ? Expression (gnat_expr) - : gnat_expr; - const Entity_Id gnat_type - = Underlying_Type (Etype (Name (gnat_node))); - const bool use_memset_p - = Is_Array_Type (gnat_type) - && Nkind (gnat_inner) == N_Aggregate - && Is_Single_Aggregate (gnat_inner); - - /* If we use memset, we need to find the innermost expression. */ - if (use_memset_p) - { - gnat_temp = gnat_inner; - do { - gnat_temp - = Expression (First (Component_Associations (gnat_temp))); - } while (Nkind (gnat_temp) == N_Aggregate - && Is_Single_Aggregate (gnat_temp)); - gnu_rhs = gnat_to_gnu (gnat_temp); - } - else - gnu_rhs = maybe_unconstrained_array (gnat_to_gnu (gnat_expr)); - - gigi_checking_assert (!Do_Range_Check (gnat_expr)); - - get_atomic_access (Name (gnat_node), &aa_type, &aa_sync); - - /* If an outer atomic access is required on the LHS, build the load- - modify-store sequence. */ - if (aa_type == OUTER_ATOMIC) - gnu_result = build_load_modify_store (gnu_lhs, gnu_rhs, gnat_node); - - /* Or else, if a simple atomic access is required, build the atomic - store. */ - else if (aa_type == SIMPLE_ATOMIC) - gnu_result = build_atomic_store (gnu_lhs, gnu_rhs, aa_sync); - - /* Or else, use memset when the conditions are met. This has already - been validated by Aggr_Assignment_OK_For_Backend in the front-end - and the RHS is thus guaranteed to be of the appropriate form. */ - else if (use_memset_p) - { - tree value - = real_zerop (gnu_rhs) - ? integer_zero_node - : fold_convert (integer_type_node, gnu_rhs); - tree dest = build_fold_addr_expr (gnu_lhs); - tree t = builtin_decl_explicit (BUILT_IN_MEMSET); - /* Be extra careful not to write too much data. */ - tree size; - if (TREE_CODE (gnu_lhs) == COMPONENT_REF) - size = DECL_SIZE_UNIT (TREE_OPERAND (gnu_lhs, 1)); - else if (DECL_P (gnu_lhs)) - size = DECL_SIZE_UNIT (gnu_lhs); - else - size = TYPE_SIZE_UNIT (TREE_TYPE (gnu_lhs)); - size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, gnu_lhs); - if (TREE_CODE (value) == INTEGER_CST && !integer_zerop (value)) - { - tree mask - = build_int_cst (integer_type_node, - ((HOST_WIDE_INT) 1 << BITS_PER_UNIT) - 1); - value = int_const_binop (BIT_AND_EXPR, value, mask); - } - gnu_result = build_call_expr (t, 3, dest, value, size); - } - - /* Otherwise build a regular assignment. */ - else - gnu_result - = build_binary_op (MODIFY_EXPR, NULL_TREE, gnu_lhs, gnu_rhs); - - /* If the assignment type is a regular array and the two sides are - not completely disjoint, play safe and use memmove. But don't do - it for a bit-packed array as it might not be byte-aligned. */ - if (TREE_CODE (gnu_result) == MODIFY_EXPR - && Is_Array_Type (gnat_type) - && !Is_Bit_Packed_Array (gnat_type) - && !(Forwards_OK (gnat_node) && Backwards_OK (gnat_node))) - { - tree to = TREE_OPERAND (gnu_result, 0); - tree from = TREE_OPERAND (gnu_result, 1); - tree type = TREE_TYPE (from); - tree size - = SUBSTITUTE_PLACEHOLDER_IN_EXPR (TYPE_SIZE_UNIT (type), from); - tree to_ptr = build_fold_addr_expr (to); - tree from_ptr = build_fold_addr_expr (from); - tree t = builtin_decl_explicit (BUILT_IN_MEMMOVE); - gnu_result = build_call_expr (t, 3, to_ptr, from_ptr, size); - } - } - break; - - case N_If_Statement: - { - tree *gnu_else_ptr; /* Point to put next "else if" or "else". */ - - /* Make the outer COND_EXPR. Avoid non-determinism. */ - gnu_result = build3 (COND_EXPR, void_type_node, - gnat_to_gnu (Condition (gnat_node)), - NULL_TREE, NULL_TREE); - COND_EXPR_THEN (gnu_result) - = build_stmt_group (Then_Statements (gnat_node), false); - TREE_SIDE_EFFECTS (gnu_result) = 1; - gnu_else_ptr = &COND_EXPR_ELSE (gnu_result); - - /* Now make a COND_EXPR for each of the "else if" parts. Put each - into the previous "else" part and point to where to put any - outer "else". Also avoid non-determinism. */ - if (Present (Elsif_Parts (gnat_node))) - for (gnat_temp = First (Elsif_Parts (gnat_node)); - Present (gnat_temp); gnat_temp = Next (gnat_temp)) - { - gnu_expr = build3 (COND_EXPR, void_type_node, - gnat_to_gnu (Condition (gnat_temp)), - NULL_TREE, NULL_TREE); - COND_EXPR_THEN (gnu_expr) - = build_stmt_group (Then_Statements (gnat_temp), false); - TREE_SIDE_EFFECTS (gnu_expr) = 1; - set_expr_location_from_node (gnu_expr, gnat_temp); - *gnu_else_ptr = gnu_expr; - gnu_else_ptr = &COND_EXPR_ELSE (gnu_expr); - } - - *gnu_else_ptr = build_stmt_group (Else_Statements (gnat_node), false); - } - break; - - case N_Case_Statement: - gnu_result = Case_Statement_to_gnu (gnat_node); - break; - - case N_Loop_Statement: - gnu_result = Loop_Statement_to_gnu (gnat_node); - break; - - case N_Block_Statement: - /* The only way to enter the block is to fall through to it. */ - if (stmt_group_may_fallthru ()) - { - start_stmt_group (); - gnat_pushlevel (); - process_decls (Declarations (gnat_node), Empty, Empty, true, true); - add_stmt (gnat_to_gnu (Handled_Statement_Sequence (gnat_node))); - gnat_poplevel (); - gnu_result = end_stmt_group (); - } - else - gnu_result = alloc_stmt_list (); - break; - - case N_Exit_Statement: - gnu_result - = build2 (EXIT_STMT, void_type_node, - (Present (Condition (gnat_node)) - ? gnat_to_gnu (Condition (gnat_node)) : NULL_TREE), - (Present (Name (gnat_node)) - ? get_gnu_tree (Entity (Name (gnat_node))) - : LOOP_STMT_LABEL (gnu_loop_stack->last ()->stmt))); - break; - - case N_Simple_Return_Statement: - { - tree gnu_ret_obj, gnu_ret_val; - - /* If the subprogram is a function, we must return the expression. */ - if (Present (Expression (gnat_node))) - { - tree gnu_subprog_type = TREE_TYPE (current_function_decl); - - /* If this function has copy-in/copy-out parameters parameters and - doesn't return by invisible reference, get the real object for - the return. See Subprogram_Body_to_gnu. */ - if (TYPE_CI_CO_LIST (gnu_subprog_type) - && !TREE_ADDRESSABLE (gnu_subprog_type)) - gnu_ret_obj = gnu_return_var_stack->last (); - else - gnu_ret_obj = DECL_RESULT (current_function_decl); - - /* Get the GCC tree for the expression to be returned. */ - gnu_ret_val = gnat_to_gnu (Expression (gnat_node)); - - /* Do not remove the padding from GNU_RET_VAL if the inner type is - self-referential since we want to allocate the fixed size. */ - if (TREE_CODE (gnu_ret_val) == COMPONENT_REF - && type_is_padding_self_referential - (TREE_TYPE (TREE_OPERAND (gnu_ret_val, 0)))) - gnu_ret_val = TREE_OPERAND (gnu_ret_val, 0); - - /* If the function returns by direct reference, return a pointer - to the return value. */ - if (TYPE_RETURN_BY_DIRECT_REF_P (gnu_subprog_type) - || By_Ref (gnat_node)) - gnu_ret_val = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_ret_val); - - /* Otherwise, if it returns an unconstrained array, we have to - allocate a new version of the result and return it. */ - else if (TYPE_RETURN_UNCONSTRAINED_P (gnu_subprog_type)) - { - gnu_ret_val = maybe_unconstrained_array (gnu_ret_val); - - /* And find out whether this is a candidate for Named Return - Value. If so, record it. */ - if (optimize - && !optimize_debug - && !TYPE_CI_CO_LIST (gnu_subprog_type)) - { - tree ret_val = gnu_ret_val; - - /* Strip useless conversions around the return value. */ - if (gnat_useless_type_conversion (ret_val)) - ret_val = TREE_OPERAND (ret_val, 0); - - /* Strip unpadding around the return value. */ - if (TREE_CODE (ret_val) == COMPONENT_REF - && TYPE_IS_PADDING_P - (TREE_TYPE (TREE_OPERAND (ret_val, 0)))) - ret_val = TREE_OPERAND (ret_val, 0); - - /* Now apply the test to the return value. */ - if (return_value_ok_for_nrv_p (NULL_TREE, ret_val)) - { - if (!f_named_ret_val) - f_named_ret_val = BITMAP_GGC_ALLOC (); - bitmap_set_bit (f_named_ret_val, DECL_UID (ret_val)); - if (!f_gnat_ret) - f_gnat_ret = gnat_node; - } - } - - gnu_ret_val = build_allocator (TREE_TYPE (gnu_ret_val), - gnu_ret_val, - TREE_TYPE (gnu_ret_obj), - Procedure_To_Call (gnat_node), - Storage_Pool (gnat_node), - gnat_node, false); - } - - /* Otherwise, if it returns by invisible reference, dereference - the pointer it is passed using the type of the return value - and build the copy operation manually. This ensures that we - don't copy too much data, for example if the return type is - unconstrained with a maximum size. */ - else if (TREE_ADDRESSABLE (gnu_subprog_type)) - { - tree gnu_ret_deref - = build_unary_op (INDIRECT_REF, TREE_TYPE (gnu_ret_val), - gnu_ret_obj); - gnu_result = build2 (INIT_EXPR, void_type_node, - gnu_ret_deref, gnu_ret_val); - add_stmt_with_node (gnu_result, gnat_node); - gnu_ret_val = NULL_TREE; - } - } - - else - gnu_ret_obj = gnu_ret_val = NULL_TREE; - - /* If we have a return label defined, convert this into a branch to - that label. The return proper will be handled elsewhere. */ - if (gnu_return_label_stack->last ()) - { - if (gnu_ret_val) - add_stmt_with_node (build_binary_op (MODIFY_EXPR, - NULL_TREE, gnu_ret_obj, - gnu_ret_val), - gnat_node); - - gnu_result = build1 (GOTO_EXPR, void_type_node, - gnu_return_label_stack->last ()); - - /* When not optimizing, make sure the return is preserved. */ - if (!optimize && Comes_From_Source (gnat_node)) - DECL_ARTIFICIAL (gnu_return_label_stack->last ()) = 0; - } - - /* Otherwise, build a regular return. */ - else - gnu_result = build_return_expr (gnu_ret_obj, gnu_ret_val); - } - break; - - case N_Goto_Statement: - gnu_expr = gnat_to_gnu (Name (gnat_node)); - gnu_result = build1 (GOTO_EXPR, void_type_node, gnu_expr); - TREE_USED (gnu_expr) = 1; - break; - - /***************************/ - /* Chapter 6: Subprograms */ - /***************************/ - - case N_Subprogram_Declaration: - /* Unless there is a freeze node, declare the entity. We consider - this a definition even though we're not generating code for the - subprogram because we will be making the corresponding GCC node. - When there is a freeze node, it is considered the definition of - the subprogram and we do nothing until after it is encountered. - That's an efficiency issue: the types involved in the profile - are far more likely to be frozen between the declaration and - the freeze node than before the declaration, so we save some - updates of the GCC node by waiting until the freeze node. - The counterpart is that we assume that there is no reference - to the subprogram between the declaration and the freeze node - in the expanded code; otherwise, it will be interpreted as an - external reference and very likely give rise to a link failure. */ - if (No (Freeze_Node (Defining_Entity (Specification (gnat_node))))) - gnat_to_gnu_entity (Defining_Entity (Specification (gnat_node)), - NULL_TREE, true); - gnu_result = alloc_stmt_list (); - break; - - case N_Abstract_Subprogram_Declaration: - /* This subprogram doesn't exist for code generation purposes, but we - have to elaborate the types of any parameters and result, unless - they are imported types (nothing to generate in this case). - - The parameter list may contain types with freeze nodes, e.g. not null - subtypes, so the subprogram itself may carry a freeze node, in which - case its elaboration must be deferred. */ - - /* Process the parameter types first. */ - if (No (Freeze_Node (Defining_Entity (Specification (gnat_node))))) - for (gnat_temp - = First_Formal_With_Extras - (Defining_Entity (Specification (gnat_node))); - Present (gnat_temp); - gnat_temp = Next_Formal_With_Extras (gnat_temp)) - if (Is_Itype (Etype (gnat_temp)) - && !From_Limited_With (Etype (gnat_temp))) - gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, false); - - /* Then the result type, set to Standard_Void_Type for procedures. */ - { - Entity_Id gnat_temp_type - = Etype (Defining_Entity (Specification (gnat_node))); - - if (Is_Itype (gnat_temp_type) && !From_Limited_With (gnat_temp_type)) - gnat_to_gnu_entity (Etype (gnat_temp_type), NULL_TREE, false); - } - - gnu_result = alloc_stmt_list (); - break; - - case N_Defining_Program_Unit_Name: - /* For a child unit identifier go up a level to get the specification. - We get this when we try to find the spec of a child unit package - that is the compilation unit being compiled. */ - gnu_result = gnat_to_gnu (Parent (gnat_node)); - break; - - case N_Subprogram_Body: - Subprogram_Body_to_gnu (gnat_node); - gnu_result = alloc_stmt_list (); - break; - - case N_Function_Call: - case N_Procedure_Call_Statement: - gnu_result = Call_to_gnu (gnat_node, &gnu_result_type, NULL_TREE, - NOT_ATOMIC, false); - break; - - /************************/ - /* Chapter 7: Packages */ - /************************/ - - case N_Package_Declaration: - gnu_result = gnat_to_gnu (Specification (gnat_node)); - break; - - case N_Package_Specification: - - start_stmt_group (); - process_decls (Visible_Declarations (gnat_node), - Private_Declarations (gnat_node), Empty, true, true); - gnu_result = end_stmt_group (); - break; - - case N_Package_Body: - - /* If this is the body of a generic package - do nothing. */ - if (Ekind (Corresponding_Spec (gnat_node)) == E_Generic_Package) - { - gnu_result = alloc_stmt_list (); - break; - } - - start_stmt_group (); - process_decls (Declarations (gnat_node), Empty, Empty, true, true); - - if (Present (Handled_Statement_Sequence (gnat_node))) - add_stmt (gnat_to_gnu (Handled_Statement_Sequence (gnat_node))); - - gnu_result = end_stmt_group (); - break; - - /********************************/ - /* Chapter 8: Visibility Rules */ - /********************************/ - - case N_Use_Package_Clause: - case N_Use_Type_Clause: - /* Nothing to do here - but these may appear in list of declarations. */ - gnu_result = alloc_stmt_list (); - break; - - /*********************/ - /* Chapter 9: Tasks */ - /*********************/ - - case N_Protected_Type_Declaration: - gnu_result = alloc_stmt_list (); - break; - - case N_Single_Task_Declaration: - gnat_to_gnu_entity (Defining_Entity (gnat_node), NULL_TREE, true); - gnu_result = alloc_stmt_list (); - break; - - /*********************************************************/ - /* Chapter 10: Program Structure and Compilation Issues */ - /*********************************************************/ - - case N_Compilation_Unit: - /* This is not called for the main unit on which gigi is invoked. */ - Compilation_Unit_to_gnu (gnat_node); - gnu_result = alloc_stmt_list (); - break; - - case N_Subunit: - gnu_result = gnat_to_gnu (Proper_Body (gnat_node)); - break; - - case N_Entry_Body: - case N_Protected_Body: - case N_Task_Body: - /* These nodes should only be present when annotating types. */ - gcc_assert (type_annotate_only); - process_decls (Declarations (gnat_node), Empty, Empty, true, true); - gnu_result = alloc_stmt_list (); - break; - - case N_Subprogram_Body_Stub: - case N_Package_Body_Stub: - case N_Protected_Body_Stub: - case N_Task_Body_Stub: - /* Simply process whatever unit is being inserted. */ - if (Present (Library_Unit (gnat_node))) - gnu_result = gnat_to_gnu (Unit (Library_Unit (gnat_node))); - else - { - gcc_assert (type_annotate_only); - gnu_result = alloc_stmt_list (); - } - break; - - /***************************/ - /* Chapter 11: Exceptions */ - /***************************/ - - case N_Handled_Sequence_Of_Statements: - /* If there is an At_End procedure attached to this node, and the EH - mechanism is front-end, we must have at least a corresponding At_End - handler, unless the No_Exception_Handlers restriction is set. */ - gcc_assert (type_annotate_only - || !Front_End_Exceptions () - || No (At_End_Proc (gnat_node)) - || Present (Exception_Handlers (gnat_node)) - || No_Exception_Handlers_Set ()); - - gnu_result = Handled_Sequence_Of_Statements_to_gnu (gnat_node); - break; - - case N_Exception_Handler: - if (Back_End_Exceptions ()) - gnu_result = Exception_Handler_to_gnu_gcc (gnat_node); - else if (Exception_Mechanism == Front_End_SJLJ) - gnu_result = Exception_Handler_to_gnu_fe_sjlj (gnat_node); - else - gcc_unreachable (); - break; - - case N_Raise_Statement: - /* Only for reraise in back-end exceptions mode. */ - gcc_assert (No (Name (gnat_node)) && Back_End_Exceptions ()); - - start_stmt_group (); - - add_stmt_with_node (build_call_n_expr (reraise_zcx_decl, 1, - gnu_incoming_exc_ptr), - gnat_node); - - gnu_result = end_stmt_group (); - break; - - case N_Push_Constraint_Error_Label: - gnu_constraint_error_label_stack.safe_push (Exception_Label (gnat_node)); - break; - - case N_Push_Storage_Error_Label: - gnu_storage_error_label_stack.safe_push (Exception_Label (gnat_node)); - break; - - case N_Push_Program_Error_Label: - gnu_program_error_label_stack.safe_push (Exception_Label (gnat_node)); - break; - - case N_Pop_Constraint_Error_Label: - gnat_temp = gnu_constraint_error_label_stack.pop (); - if (Present (gnat_temp) - && !TREE_USED (gnat_to_gnu_entity (gnat_temp, NULL_TREE, false)) - && No_Exception_Propagation_Active ()) - Warn_If_No_Local_Raise (gnat_temp); - break; - - case N_Pop_Storage_Error_Label: - gnat_temp = gnu_storage_error_label_stack.pop (); - if (Present (gnat_temp) - && !TREE_USED (gnat_to_gnu_entity (gnat_temp, NULL_TREE, false)) - && No_Exception_Propagation_Active ()) - Warn_If_No_Local_Raise (gnat_temp); - break; - - case N_Pop_Program_Error_Label: - gnat_temp = gnu_program_error_label_stack.pop (); - if (Present (gnat_temp) - && !TREE_USED (gnat_to_gnu_entity (gnat_temp, NULL_TREE, false)) - && No_Exception_Propagation_Active ()) - Warn_If_No_Local_Raise (gnat_temp); - break; - - /******************************/ - /* Chapter 12: Generic Units */ - /******************************/ - - case N_Generic_Function_Renaming_Declaration: - case N_Generic_Package_Renaming_Declaration: - case N_Generic_Procedure_Renaming_Declaration: - case N_Generic_Package_Declaration: - case N_Generic_Subprogram_Declaration: - case N_Package_Instantiation: - case N_Procedure_Instantiation: - case N_Function_Instantiation: - /* These nodes can appear on a declaration list but there is nothing to - to be done with them. */ - gnu_result = alloc_stmt_list (); - break; - - /**************************************************/ - /* Chapter 13: Representation Clauses and */ - /* Implementation-Dependent Features */ - /**************************************************/ - - case N_Attribute_Definition_Clause: - gnu_result = alloc_stmt_list (); - - /* The only one we need to deal with is 'Address since, for the others, - the front-end puts the information elsewhere. */ - if (Get_Attribute_Id (Chars (gnat_node)) != Attr_Address) - break; - - /* And we only deal with 'Address if the object has a Freeze node. */ - gnat_temp = Entity (Name (gnat_node)); - if (Freeze_Node (gnat_temp)) - { - tree gnu_address = gnat_to_gnu (Expression (gnat_node)), gnu_temp; - - /* Get the value to use as the address and save it as the equivalent - for the object; when it is frozen, gnat_to_gnu_entity will do the - right thing. For a subprogram, put the naked address but build a - meaningfull expression for an object in case its address is taken - before the Freeze node is encountered; this can happen if the type - of the object is limited and it is initialized with the result of - a function call. */ - if (Is_Subprogram (gnat_temp)) - gnu_temp = gnu_address; - else - { - tree gnu_type = gnat_to_gnu_type (Etype (gnat_temp)); - /* Drop atomic and volatile qualifiers for the expression. */ - gnu_type = TYPE_MAIN_VARIANT (gnu_type); - gnu_type - = build_reference_type_for_mode (gnu_type, ptr_mode, true); - gnu_address = convert (gnu_type, gnu_address); - gnu_temp - = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_address); - } - - save_gnu_tree (gnat_temp, gnu_temp, true); - } - break; - - case N_Enumeration_Representation_Clause: - case N_Record_Representation_Clause: - case N_At_Clause: - /* We do nothing with these. SEM puts the information elsewhere. */ - gnu_result = alloc_stmt_list (); - break; - - case N_Code_Statement: - if (!type_annotate_only) - { - tree gnu_template = gnat_to_gnu (Asm_Template (gnat_node)); - tree gnu_inputs = NULL_TREE, gnu_outputs = NULL_TREE; - tree gnu_clobbers = NULL_TREE, tail; - bool allows_mem, allows_reg, fake; - int ninputs, noutputs, i; - const char **oconstraints; - const char *constraint; - char *clobber; - - /* First retrieve the 3 operand lists built by the front-end. */ - Setup_Asm_Outputs (gnat_node); - while (Present (gnat_temp = Asm_Output_Variable ())) - { - tree gnu_value = gnat_to_gnu (gnat_temp); - tree gnu_constr = build_tree_list (NULL_TREE, gnat_to_gnu - (Asm_Output_Constraint ())); - - gnu_outputs = tree_cons (gnu_constr, gnu_value, gnu_outputs); - Next_Asm_Output (); - } - - Setup_Asm_Inputs (gnat_node); - while (Present (gnat_temp = Asm_Input_Value ())) - { - tree gnu_value = gnat_to_gnu (gnat_temp); - tree gnu_constr = build_tree_list (NULL_TREE, gnat_to_gnu - (Asm_Input_Constraint ())); - - gnu_inputs = tree_cons (gnu_constr, gnu_value, gnu_inputs); - Next_Asm_Input (); - } - - Clobber_Setup (gnat_node); - while ((clobber = (char *) Clobber_Get_Next ())) - gnu_clobbers - = tree_cons (NULL_TREE, - build_string (strlen (clobber) + 1, clobber), - gnu_clobbers); - - /* Then perform some standard checking and processing on the - operands. In particular, mark them addressable if needed. */ - gnu_outputs = nreverse (gnu_outputs); - noutputs = list_length (gnu_outputs); - gnu_inputs = nreverse (gnu_inputs); - ninputs = list_length (gnu_inputs); - oconstraints = XALLOCAVEC (const char *, noutputs); - - for (i = 0, tail = gnu_outputs; tail; ++i, tail = TREE_CHAIN (tail)) - { - tree output = TREE_VALUE (tail); - constraint - = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); - oconstraints[i] = constraint; - - if (parse_output_constraint (&constraint, i, ninputs, noutputs, - &allows_mem, &allows_reg, &fake)) - { - /* If the operand is going to end up in memory, - mark it addressable. Note that we don't test - allows_mem like in the input case below; this - is modeled on the C front-end. */ - if (!allows_reg) - { - output = remove_conversions (output, false); - if (TREE_CODE (output) == CONST_DECL - && DECL_CONST_CORRESPONDING_VAR (output)) - output = DECL_CONST_CORRESPONDING_VAR (output); - if (!gnat_mark_addressable (output)) - output = error_mark_node; - } - } - else - output = error_mark_node; - - TREE_VALUE (tail) = output; - } - - for (i = 0, tail = gnu_inputs; tail; ++i, tail = TREE_CHAIN (tail)) - { - tree input = TREE_VALUE (tail); - constraint - = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail))); - - if (parse_input_constraint (&constraint, i, ninputs, noutputs, - 0, oconstraints, - &allows_mem, &allows_reg)) - { - /* If the operand is going to end up in memory, - mark it addressable. */ - if (!allows_reg && allows_mem) - { - input = remove_conversions (input, false); - if (TREE_CODE (input) == CONST_DECL - && DECL_CONST_CORRESPONDING_VAR (input)) - input = DECL_CONST_CORRESPONDING_VAR (input); - if (!gnat_mark_addressable (input)) - input = error_mark_node; - } - } - else - input = error_mark_node; - - TREE_VALUE (tail) = input; - } - - gnu_result = build5 (ASM_EXPR, void_type_node, - gnu_template, gnu_outputs, - gnu_inputs, gnu_clobbers, NULL_TREE); - ASM_VOLATILE_P (gnu_result) = Is_Asm_Volatile (gnat_node); - } - else - gnu_result = alloc_stmt_list (); - - break; - - /****************/ - /* Added Nodes */ - /****************/ - - /* Markers are created by the ABE mechanism to capture information which - is either unavailable of expensive to recompute. Markers do not have - and runtime semantics, and should be ignored. */ - - case N_Call_Marker: - case N_Variable_Reference_Marker: - gnu_result = alloc_stmt_list (); - break; - - case N_Expression_With_Actions: - /* This construct doesn't define a scope so we don't push a binding - level around the statement list, but we wrap it in a SAVE_EXPR to - protect it from unsharing. Elaborate the expression as part of the - same statement group as the actions so that the type declaration - gets inserted there as well. This ensures that the type elaboration - code is issued past the actions computing values on which it might - depend. */ - start_stmt_group (); - add_stmt_list (Actions (gnat_node)); - gnu_expr = gnat_to_gnu (Expression (gnat_node)); - gnu_result = end_stmt_group (); - - gnu_result = build1 (SAVE_EXPR, void_type_node, gnu_result); - TREE_SIDE_EFFECTS (gnu_result) = 1; - - gnu_result - = build_compound_expr (TREE_TYPE (gnu_expr), gnu_result, gnu_expr); - gnu_result_type = get_unpadded_type (Etype (gnat_node)); - break; - - case N_Freeze_Entity: - start_stmt_group (); - process_freeze_entity (gnat_node); - process_decls (Actions (gnat_node), Empty, Empty, true, true); - gnu_result = end_stmt_group (); - break; - - case N_Freeze_Generic_Entity: - gnu_result = alloc_stmt_list (); - break; - - case N_Itype_Reference: - if (!present_gnu_tree (Itype (gnat_node))) - process_type (Itype (gnat_node)); - gnu_result = alloc_stmt_list (); - break; - - case N_Free_Statement: - gnat_temp = Expression (gnat_node); - - if (!type_annotate_only) - { - tree gnu_ptr, gnu_ptr_type, gnu_obj_type, gnu_actual_obj_type; - - const Entity_Id gnat_desig_type - = Designated_Type (Underlying_Type (Etype (gnat_temp))); - - /* Make sure the designated type is complete before dereferencing, - in case it is a Taft Amendment type. */ - (void) gnat_to_gnu_entity (gnat_desig_type, NULL_TREE, false); - - gnu_ptr = gnat_to_gnu (gnat_temp); - gnu_ptr_type = TREE_TYPE (gnu_ptr); - - /* If this is a thin pointer, we must first dereference it to create - a fat pointer, then go back below to a thin pointer. The reason - for this is that we need to have a fat pointer someplace in order - to properly compute the size. */ - if (TYPE_IS_THIN_POINTER_P (TREE_TYPE (gnu_ptr))) - gnu_ptr = build_unary_op (ADDR_EXPR, NULL_TREE, - build_unary_op (INDIRECT_REF, NULL_TREE, - gnu_ptr)); - - /* If this is a fat pointer, the object must have been allocated with - the template in front of the array. So pass the template address, - and get the total size; do it by converting to a thin pointer. */ - if (TYPE_IS_FAT_POINTER_P (TREE_TYPE (gnu_ptr))) - gnu_ptr - = convert (build_pointer_type - (TYPE_OBJECT_RECORD_TYPE - (TYPE_UNCONSTRAINED_ARRAY (TREE_TYPE (gnu_ptr)))), - gnu_ptr); - - gnu_obj_type = TREE_TYPE (TREE_TYPE (gnu_ptr)); - - /* If this is a thin pointer, the object must have been allocated with - the template in front of the array. So pass the template address, - and get the total size. */ - if (TYPE_IS_THIN_POINTER_P (TREE_TYPE (gnu_ptr))) - gnu_ptr - = build_binary_op (POINTER_PLUS_EXPR, TREE_TYPE (gnu_ptr), - gnu_ptr, - fold_build1 (NEGATE_EXPR, sizetype, - byte_position - (DECL_CHAIN - TYPE_FIELDS ((gnu_obj_type))))); - - /* If we have a special dynamic constrained subtype on the node, use - it to compute the size; otherwise, use the designated subtype. */ - if (Present (Actual_Designated_Subtype (gnat_node))) - { - gnu_actual_obj_type - = gnat_to_gnu_type (Actual_Designated_Subtype (gnat_node)); - - if (TYPE_IS_FAT_OR_THIN_POINTER_P (gnu_ptr_type)) - gnu_actual_obj_type - = build_unc_object_type_from_ptr (gnu_ptr_type, - gnu_actual_obj_type, - get_identifier ("DEALLOC"), - false); - } - else - gnu_actual_obj_type = gnu_obj_type; - - tree gnu_size = TYPE_SIZE_UNIT (gnu_actual_obj_type); - gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (gnu_size, gnu_ptr); - - gnu_result - = build_call_alloc_dealloc (gnu_ptr, gnu_size, gnu_obj_type, - Procedure_To_Call (gnat_node), - Storage_Pool (gnat_node), - gnat_node); - } - break; - - case N_Raise_Constraint_Error: - case N_Raise_Program_Error: - case N_Raise_Storage_Error: - if (type_annotate_only) - gnu_result = alloc_stmt_list (); - else - gnu_result = Raise_Error_to_gnu (gnat_node, &gnu_result_type); - break; - - case N_Validate_Unchecked_Conversion: - /* The only validation we currently do on an unchecked conversion is - that of aliasing assumptions. */ - if (flag_strict_aliasing) - gnat_validate_uc_list.safe_push (gnat_node); - gnu_result = alloc_stmt_list (); - break; - - case N_Function_Specification: - case N_Procedure_Specification: - case N_Op_Concat: - case N_Component_Association: - /* These nodes should only be present when annotating types. */ - gcc_assert (type_annotate_only); - gnu_result = alloc_stmt_list (); - break; - - default: - /* Other nodes are not supposed to reach here. */ - gcc_unreachable (); - } - - /* If we are in the elaboration procedure, check if we are violating the - No_Elaboration_Code restriction by having a non-empty statement. */ - if (statement_node_p (gnat_node) - && !(TREE_CODE (gnu_result) == STATEMENT_LIST - && empty_stmt_list_p (gnu_result)) - && current_function_decl == get_elaboration_procedure ()) - Check_Elaboration_Code_Allowed (gnat_node); - - /* If we pushed the processing of the elaboration routine, pop it back. */ - if (went_into_elab_proc) - current_function_decl = NULL_TREE; - - /* When not optimizing, turn boolean rvalues B into B != false tests - so that we can put the location information of the reference to B on - the inequality operator for better debug info. */ - if (!optimize - && TREE_CODE (gnu_result) != INTEGER_CST - && TREE_CODE (gnu_result) != TYPE_DECL - && (kind == N_Identifier - || kind == N_Expanded_Name - || kind == N_Explicit_Dereference - || kind == N_Indexed_Component - || kind == N_Selected_Component) - && TREE_CODE (get_base_type (gnu_result_type)) == BOOLEAN_TYPE - && Nkind (Parent (gnat_node)) != N_Attribute_Reference - && Nkind (Parent (gnat_node)) != N_Pragma_Argument_Association - && Nkind (Parent (gnat_node)) != N_Variant_Part - && !lvalue_required_p (gnat_node, gnu_result_type, false, false)) - { - gnu_result - = build_binary_op (NE_EXPR, gnu_result_type, - convert (gnu_result_type, gnu_result), - convert (gnu_result_type, boolean_false_node)); - if (TREE_CODE (gnu_result) != INTEGER_CST) - set_gnu_expr_location_from_node (gnu_result, gnat_node); - } - - /* Set the location information on the result if it's not a simple name - or something that contains a simple name, for example a tag, because - we don"t want all the references to get the location of the first use. - Note that we may have no result if we tried to build a CALL_EXPR node - to a procedure with no side-effects and optimization is enabled. */ - else if (kind != N_Identifier - && !(kind == N_Selected_Component - && Chars (Selector_Name (gnat_node)) == Name_uTag) - && gnu_result - && EXPR_P (gnu_result)) - set_gnu_expr_location_from_node (gnu_result, gnat_node); - - /* If we're supposed to return something of void_type, it means we have - something we're elaborating for effect, so just return. */ - if (TREE_CODE (gnu_result_type) == VOID_TYPE) - return gnu_result; - - /* If the result is a constant that overflowed, raise Constraint_Error. */ - if (TREE_CODE (gnu_result) == INTEGER_CST && TREE_OVERFLOW (gnu_result)) - { - post_error ("??Constraint_Error will be raised at run time", gnat_node); - gnu_result - = build1 (NULL_EXPR, gnu_result_type, - build_call_raise (CE_Overflow_Check_Failed, gnat_node, - N_Raise_Constraint_Error)); - } - - /* If the result has side-effects and is of an unconstrained type, protect - the expression in case it will be referenced multiple times, i.e. for - its value and to compute the size of an object. But do it neither for - an object nor a renaming declaration, nor a return statement of a call - to a function that returns an unconstrained record type with default - discriminant, because there is no size to be computed in these cases - and this will create a useless temporary. We must do this before any - conversions. */ - if (TREE_SIDE_EFFECTS (gnu_result) - && (TREE_CODE (gnu_result_type) == UNCONSTRAINED_ARRAY_TYPE - || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_result_type))) - && !(TREE_CODE (gnu_result) == CALL_EXPR - && type_is_padding_self_referential (TREE_TYPE (gnu_result)) - && (Nkind (Parent (gnat_node)) == N_Object_Declaration - || Nkind (Parent (gnat_node)) == N_Object_Renaming_Declaration - || Nkind (Parent (gnat_node)) == N_Simple_Return_Statement))) - gnu_result = gnat_protect_expr (gnu_result); - - /* Now convert the result to the result type, unless we are in one of the - following cases: - - 1. If this is the LHS of an assignment or an actual parameter of a - call, return the result almost unmodified since the RHS will have - to be converted to our type in that case, unless the result type - has a simpler size or for array types because this size might be - changed in-between. Likewise if there is just a no-op unchecked - conversion in-between. Similarly, don't convert integral types - that are the operands of an unchecked conversion since we need - to ignore those conversions (for 'Valid). - - 2. If we have a label (which doesn't have any well-defined type), a - field or an error, return the result almost unmodified. Similarly, - if the two types are record types with the same name, don't convert. - This will be the case when we are converting from a packable version - of a type to its original type and we need those conversions to be - NOPs in order for assignments into these types to work properly. - - 3. If the type is void or if we have no result, return error_mark_node - to show we have no result. - - 4. If this is a call to a function that returns with variable size and - the call is used as the expression in either an object or a renaming - declaration, return the result unmodified because we want to use the - return slot optimization in this case. - - 5. If this is a reference to an unconstrained array which is used as the - prefix of an attribute reference that requires an lvalue, return the - result unmodified because we want to return the original bounds. - - 6. Finally, if the type of the result is already correct. */ - - if (Present (Parent (gnat_node)) - && (lhs_or_actual_p (gnat_node) - || (Nkind (Parent (gnat_node)) == N_Unchecked_Type_Conversion - && unchecked_conversion_nop (Parent (gnat_node))) - || (Nkind (Parent (gnat_node)) == N_Unchecked_Type_Conversion - && !AGGREGATE_TYPE_P (gnu_result_type) - && !AGGREGATE_TYPE_P (TREE_TYPE (gnu_result)))) - && !(TYPE_SIZE (gnu_result_type) - && TYPE_SIZE (TREE_TYPE (gnu_result)) - && AGGREGATE_TYPE_P (gnu_result_type) - == AGGREGATE_TYPE_P (TREE_TYPE (gnu_result)) - && ((TREE_CODE (TYPE_SIZE (gnu_result_type)) == INTEGER_CST - && (TREE_CODE (TYPE_SIZE (TREE_TYPE (gnu_result))) - != INTEGER_CST)) - || (TREE_CODE (TYPE_SIZE (gnu_result_type)) != INTEGER_CST - && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_result_type)) - && (CONTAINS_PLACEHOLDER_P - (TYPE_SIZE (TREE_TYPE (gnu_result))))) - || (TREE_CODE (gnu_result_type) == ARRAY_TYPE - && TREE_CODE (TREE_TYPE (gnu_result)) == ARRAY_TYPE)) - && !(TREE_CODE (gnu_result_type) == RECORD_TYPE - && TYPE_JUSTIFIED_MODULAR_P (gnu_result_type)))) - { - /* Remove padding only if the inner object is of self-referential - size: in that case it must be an object of unconstrained type - with a default discriminant and we want to avoid copying too - much data. But do not remove it if it is already too small. */ - if (type_is_padding_self_referential (TREE_TYPE (gnu_result)) - && !(TREE_CODE (gnu_result) == COMPONENT_REF - && DECL_BIT_FIELD (TREE_OPERAND (gnu_result, 1)) - && DECL_SIZE (TREE_OPERAND (gnu_result, 1)) - != TYPE_SIZE (TREE_TYPE (gnu_result)))) - gnu_result = convert (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_result))), - gnu_result); - } - - else if (TREE_CODE (gnu_result) == LABEL_DECL - || TREE_CODE (gnu_result) == FIELD_DECL - || TREE_CODE (gnu_result) == ERROR_MARK - || (TYPE_NAME (gnu_result_type) - == TYPE_NAME (TREE_TYPE (gnu_result)) - && TREE_CODE (gnu_result_type) == RECORD_TYPE - && TREE_CODE (TREE_TYPE (gnu_result)) == RECORD_TYPE)) - { - /* Remove any padding. */ - gnu_result = maybe_padded_object (gnu_result); - } - - else if (gnu_result == error_mark_node || gnu_result_type == void_type_node) - gnu_result = error_mark_node; - - else if (TREE_CODE (gnu_result) == CALL_EXPR - && Present (Parent (gnat_node)) - && (Nkind (Parent (gnat_node)) == N_Object_Declaration - || Nkind (Parent (gnat_node)) == N_Object_Renaming_Declaration) - && return_type_with_variable_size_p (TREE_TYPE (gnu_result))) - ; - - else if (TREE_CODE (gnu_result) == UNCONSTRAINED_ARRAY_REF - && Present (Parent (gnat_node)) - && Nkind (Parent (gnat_node)) == N_Attribute_Reference - && lvalue_required_for_attribute_p (Parent (gnat_node))) - ; - - else if (TREE_TYPE (gnu_result) != gnu_result_type) - gnu_result = convert (gnu_result_type, gnu_result); - - /* We don't need any NOP_EXPR or NON_LVALUE_EXPR on the result. */ - while ((TREE_CODE (gnu_result) == NOP_EXPR - || TREE_CODE (gnu_result) == NON_LVALUE_EXPR) - && TREE_TYPE (TREE_OPERAND (gnu_result, 0)) == TREE_TYPE (gnu_result)) - gnu_result = TREE_OPERAND (gnu_result, 0); - - return gnu_result; -} - -/* Similar to gnat_to_gnu, but discard any object that might be created in - the course of the translation of GNAT_NODE, which must be an "external" - expression in the sense that it will be elaborated elsewhere. */ - -tree -gnat_to_gnu_external (Node_Id gnat_node) -{ - const int save_force_global = force_global; - bool went_into_elab_proc; - - /* Force the local context and create a fake scope that we zap - at the end so declarations will not be stuck either in the - global varpool or in the current scope. */ - if (!current_function_decl) - { - current_function_decl = get_elaboration_procedure (); - went_into_elab_proc = true; - } - else - went_into_elab_proc = false; - force_global = 0; - gnat_pushlevel (); - - tree gnu_result = gnat_to_gnu (gnat_node); - - gnat_zaplevel (); - force_global = save_force_global; - if (went_into_elab_proc) - current_function_decl = NULL_TREE; - - /* Do not import locations from external units. */ - if (gnu_result && EXPR_P (gnu_result)) - SET_EXPR_LOCATION (gnu_result, UNKNOWN_LOCATION); - - return gnu_result; -} - -/* Return true if the statement list STMT_LIST is empty. */ - -static bool -empty_stmt_list_p (tree stmt_list) -{ - tree_stmt_iterator tsi; - - for (tsi = tsi_start (stmt_list); !tsi_end_p (tsi); tsi_next (&tsi)) - { - tree stmt = tsi_stmt (tsi); - - /* Anything else than an empty STMT_STMT counts as something. */ - if (TREE_CODE (stmt) != STMT_STMT || STMT_STMT_STMT (stmt)) - return false; - } - - return true; -} - -/* Record the current code position in GNAT_NODE. */ - -static void -record_code_position (Node_Id gnat_node) -{ - tree stmt_stmt = build1 (STMT_STMT, void_type_node, NULL_TREE); - - add_stmt_with_node (stmt_stmt, gnat_node); - save_gnu_tree (gnat_node, stmt_stmt, true); -} - -/* Insert the code for GNAT_NODE at the position saved for that node. */ - -static void -insert_code_for (Node_Id gnat_node) -{ - tree code = gnat_to_gnu (gnat_node); - - /* It's too late to remove the STMT_STMT itself at this point. */ - if (!empty_stmt_list_p (code)) - STMT_STMT_STMT (get_gnu_tree (gnat_node)) = code; - - save_gnu_tree (gnat_node, NULL_TREE, true); -} - -/* Start a new statement group chained to the previous group. */ - -void -start_stmt_group (void) -{ - struct stmt_group *group = stmt_group_free_list; - - /* First see if we can get one from the free list. */ - if (group) - stmt_group_free_list = group->previous; - else - group = ggc_alloc<stmt_group> (); - - group->previous = current_stmt_group; - group->stmt_list = group->block = group->cleanups = NULL_TREE; - current_stmt_group = group; -} - -/* Add GNU_STMT to the current statement group. If it is an expression with - no effects, it is ignored. */ - -void -add_stmt (tree gnu_stmt) -{ - append_to_statement_list (gnu_stmt, ¤t_stmt_group->stmt_list); -} - -/* Similar, but the statement is always added, regardless of side-effects. */ - -void -add_stmt_force (tree gnu_stmt) -{ - append_to_statement_list_force (gnu_stmt, ¤t_stmt_group->stmt_list); -} - -/* Like add_stmt, but set the location of GNU_STMT to that of GNAT_NODE. */ - -void -add_stmt_with_node (tree gnu_stmt, Node_Id gnat_node) -{ - if (Present (gnat_node)) - set_expr_location_from_node (gnu_stmt, gnat_node); - add_stmt (gnu_stmt); -} - -/* Similar, but the statement is always added, regardless of side-effects. */ - -void -add_stmt_with_node_force (tree gnu_stmt, Node_Id gnat_node) -{ - if (Present (gnat_node)) - set_expr_location_from_node (gnu_stmt, gnat_node); - add_stmt_force (gnu_stmt); -} - -/* Add a declaration statement for GNU_DECL to the current statement group. - Get the SLOC to be put onto the statement from GNAT_NODE. */ - -void -add_decl_expr (tree gnu_decl, Node_Id gnat_node) -{ - tree type = TREE_TYPE (gnu_decl); - tree gnu_stmt, gnu_init; - - /* If this is a variable that Gigi is to ignore, we may have been given - an ERROR_MARK. So test for it. We also might have been given a - reference for a renaming. So only do something for a decl. Also - ignore a TYPE_DECL for an UNCONSTRAINED_ARRAY_TYPE. */ - if (!DECL_P (gnu_decl) - || (TREE_CODE (gnu_decl) == TYPE_DECL - && TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE)) - return; - - gnu_stmt = build1 (DECL_EXPR, void_type_node, gnu_decl); - - /* If we are external or global, we don't want to output the DECL_EXPR for - this DECL node since we already have evaluated the expressions in the - sizes and positions as globals and doing it again would be wrong. */ - if (DECL_EXTERNAL (gnu_decl) || global_bindings_p ()) - { - /* Mark everything as used to prevent node sharing with subprograms. - Note that walk_tree knows how to deal with TYPE_DECL, but neither - VAR_DECL nor CONST_DECL. This appears to be somewhat arbitrary. */ - MARK_VISITED (gnu_stmt); - if (TREE_CODE (gnu_decl) == VAR_DECL - || TREE_CODE (gnu_decl) == CONST_DECL) - { - MARK_VISITED (DECL_SIZE (gnu_decl)); - MARK_VISITED (DECL_SIZE_UNIT (gnu_decl)); - MARK_VISITED (DECL_INITIAL (gnu_decl)); - } - } - else - add_stmt_with_node (gnu_stmt, gnat_node); - - /* Mark our TYPE_ADA_SIZE field now since it will not be gimplified. */ - if (TREE_CODE (gnu_decl) == TYPE_DECL - && RECORD_OR_UNION_TYPE_P (type) - && !TYPE_FAT_POINTER_P (type)) - MARK_VISITED (TYPE_ADA_SIZE (type)); - - /* If this is a variable and an initializer is attached to it, it must be - valid for the context. Similar to init_const in create_var_decl. */ - if (TREE_CODE (gnu_decl) == VAR_DECL - && (gnu_init = DECL_INITIAL (gnu_decl)) - && (!gnat_types_compatible_p (type, TREE_TYPE (gnu_init)) - || (TREE_STATIC (gnu_decl) - && !initializer_constant_valid_p (gnu_init, - TREE_TYPE (gnu_init))))) - { - DECL_INITIAL (gnu_decl) = NULL_TREE; - if (TREE_READONLY (gnu_decl)) - { - TREE_READONLY (gnu_decl) = 0; - DECL_READONLY_ONCE_ELAB (gnu_decl) = 1; - } - - /* Remove any padding so the assignment is done properly. */ - gnu_decl = maybe_padded_object (gnu_decl); - - gnu_stmt = build_binary_op (INIT_EXPR, NULL_TREE, gnu_decl, gnu_init); - add_stmt_with_node (gnu_stmt, gnat_node); - } -} - -/* Callback for walk_tree to mark the visited trees rooted at *TP. */ - -static tree -mark_visited_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED) -{ - tree t = *tp; - - if (TREE_VISITED (t)) - *walk_subtrees = 0; - - /* Don't mark a dummy type as visited because we want to mark its sizes - and fields once it's filled in. */ - else if (!TYPE_IS_DUMMY_P (t)) - TREE_VISITED (t) = 1; - - /* The test in gimplify_type_sizes is on the main variant. */ - if (TYPE_P (t)) - TYPE_SIZES_GIMPLIFIED (TYPE_MAIN_VARIANT (t)) = 1; - - return NULL_TREE; -} - -/* Mark nodes rooted at T with TREE_VISITED and types as having their - sized gimplified. We use this to indicate all variable sizes and - positions in global types may not be shared by any subprogram. */ - -void -mark_visited (tree t) -{ - walk_tree (&t, mark_visited_r, NULL, NULL); -} - -/* Add GNU_CLEANUP, a cleanup action, to the current code group and - set its location to that of GNAT_NODE if present, but with column info - cleared so that conditional branches generated as part of the cleanup - code do not interfere with coverage analysis tools. */ - -static void -add_cleanup (tree gnu_cleanup, Node_Id gnat_node) -{ - if (Present (gnat_node)) - set_expr_location_from_node (gnu_cleanup, gnat_node, true); - - /* An EH_ELSE_EXPR must be by itself, and that's all we need when we - use it. The assert below makes sure that is so. Should we ever - need more than that, we could combine EH_ELSE_EXPRs, and copy - non-EH_ELSE_EXPR stmts into both cleanup paths of an - EH_ELSE_EXPR. */ - if (TREE_CODE (gnu_cleanup) == EH_ELSE_EXPR) - { - gcc_assert (!current_stmt_group->cleanups); - current_stmt_group->cleanups = gnu_cleanup; - } - else - { - gcc_assert (!current_stmt_group->cleanups - || (TREE_CODE (current_stmt_group->cleanups) - != EH_ELSE_EXPR)); - append_to_statement_list (gnu_cleanup, ¤t_stmt_group->cleanups); - } -} - -/* Set the BLOCK node corresponding to the current code group to GNU_BLOCK. */ - -void -set_block_for_group (tree gnu_block) -{ - gcc_assert (!current_stmt_group->block); - current_stmt_group->block = gnu_block; -} - -/* Return code corresponding to the current code group. It is normally - a STATEMENT_LIST, but may also be a BIND_EXPR or TRY_FINALLY_EXPR if - BLOCK or cleanups were set. */ - -tree -end_stmt_group (void) -{ - struct stmt_group *group = current_stmt_group; - tree gnu_retval = group->stmt_list; - - /* If this is a null list, allocate a new STATEMENT_LIST. Then, if there - are cleanups, make a TRY_FINALLY_EXPR. Last, if there is a BLOCK, - make a BIND_EXPR. Note that we nest in that because the cleanup may - reference variables in the block. */ - if (!gnu_retval) - gnu_retval = alloc_stmt_list (); - - if (group->cleanups) - gnu_retval = build2 (TRY_FINALLY_EXPR, void_type_node, gnu_retval, - group->cleanups); - - if (current_stmt_group->block) - gnu_retval = build3 (BIND_EXPR, void_type_node, BLOCK_VARS (group->block), - gnu_retval, group->block); - - /* Remove this group from the stack and add it to the free list. */ - current_stmt_group = group->previous; - group->previous = stmt_group_free_list; - stmt_group_free_list = group; - - return gnu_retval; -} - -/* Return whether the current statement group may fall through. */ - -static inline bool -stmt_group_may_fallthru (void) -{ - if (current_stmt_group->stmt_list) - return block_may_fallthru (current_stmt_group->stmt_list); - else - return true; -} - -/* Add a list of statements from GNAT_LIST, a possibly-empty list of - statements.*/ - -static void -add_stmt_list (List_Id gnat_list) -{ - Node_Id gnat_node; - - if (Present (gnat_list)) - for (gnat_node = First (gnat_list); Present (gnat_node); - gnat_node = Next (gnat_node)) - add_stmt (gnat_to_gnu (gnat_node)); -} - -/* Build a tree from GNAT_LIST, a possibly-empty list of statements. - If BINDING_P is true, push and pop a binding level around the list. */ - -static tree -build_stmt_group (List_Id gnat_list, bool binding_p) -{ - start_stmt_group (); - - if (binding_p) - gnat_pushlevel (); - - add_stmt_list (gnat_list); - - if (binding_p) - gnat_poplevel (); - - return end_stmt_group (); -} - -/* Generate GIMPLE in place for the expression at *EXPR_P. */ - -int -gnat_gimplify_expr (tree *expr_p, gimple_seq *pre_p, - gimple_seq *post_p ATTRIBUTE_UNUSED) -{ - tree expr = *expr_p; - tree type = TREE_TYPE (expr); - tree op; - - if (IS_ADA_STMT (expr)) - return gnat_gimplify_stmt (expr_p); - - switch (TREE_CODE (expr)) - { - case NULL_EXPR: - /* If this is an aggregate type, build a null pointer of the appropriate - type and dereference it. */ - if (AGGREGATE_TYPE_P (type) - || TREE_CODE (type) == UNCONSTRAINED_ARRAY_TYPE) - *expr_p = build_unary_op (INDIRECT_REF, NULL_TREE, - convert (build_pointer_type (type), - integer_zero_node)); - /* Otherwise, just make a VAR_DECL. */ - else - { - *expr_p = create_tmp_var (type, NULL); - suppress_warning (*expr_p); - } - - gimplify_and_add (TREE_OPERAND (expr, 0), pre_p); - return GS_OK; - - case UNCONSTRAINED_ARRAY_REF: - /* We should only do this if we are just elaborating for side-effects, - but we can't know that yet. */ - *expr_p = TREE_OPERAND (*expr_p, 0); - return GS_OK; - - case ADDR_EXPR: - op = TREE_OPERAND (expr, 0); - - /* If we are taking the address of a constant CONSTRUCTOR, make sure it - is put into static memory. We know that it's going to be read-only - given the semantics we have and it must be in static memory when the - reference is in an elaboration procedure. */ - if (TREE_CODE (op) == CONSTRUCTOR && TREE_CONSTANT (op)) - { - tree addr = build_fold_addr_expr (tree_output_constant_def (op)); - *expr_p = fold_convert (type, addr); - return GS_ALL_DONE; - } - - /* Replace atomic loads with their first argument. That's necessary - because the gimplifier would create a temporary otherwise. */ - if (TREE_SIDE_EFFECTS (op)) - while (handled_component_p (op) || CONVERT_EXPR_P (op)) - { - tree inner = TREE_OPERAND (op, 0); - if (TREE_CODE (inner) == CALL_EXPR && call_is_atomic_load (inner)) - { - tree t = CALL_EXPR_ARG (inner, 0); - if (TREE_CODE (t) == NOP_EXPR) - t = TREE_OPERAND (t, 0); - if (TREE_CODE (t) == ADDR_EXPR) - TREE_OPERAND (op, 0) = TREE_OPERAND (t, 0); - else - TREE_OPERAND (op, 0) = build_fold_indirect_ref (t); - } - else - op = inner; - } - - return GS_UNHANDLED; - - case CALL_EXPR: - /* If we are passing a constant fat pointer CONSTRUCTOR, make sure it is - put into static memory; this performs a restricted version of constant - propagation on fat pointers in calls. But do not do it for strings to - avoid blocking concatenation in the caller when it is inlined. */ - for (int i = 0; i < call_expr_nargs (expr); i++) - { - tree arg = *(CALL_EXPR_ARGP (expr) + i); - - if (TREE_CODE (arg) == CONSTRUCTOR - && TREE_CONSTANT (arg) - && TYPE_IS_FAT_POINTER_P (TREE_TYPE (arg))) - { - tree t = CONSTRUCTOR_ELT (arg, 0)->value; - if (TREE_CODE (t) == NOP_EXPR) - t = TREE_OPERAND (t, 0); - if (TREE_CODE (t) == ADDR_EXPR) - t = TREE_OPERAND (t, 0); - if (TREE_CODE (t) != STRING_CST) - *(CALL_EXPR_ARGP (expr) + i) = tree_output_constant_def (arg); - } - } - - return GS_UNHANDLED; - - case VIEW_CONVERT_EXPR: - op = TREE_OPERAND (expr, 0); - - /* If we are view-converting a CONSTRUCTOR or a call from an aggregate - type to a scalar one, explicitly create the local temporary. That's - required if the type is passed by reference. */ - if ((TREE_CODE (op) == CONSTRUCTOR || TREE_CODE (op) == CALL_EXPR) - && AGGREGATE_TYPE_P (TREE_TYPE (op)) - && !AGGREGATE_TYPE_P (type)) - { - tree mod, new_var = create_tmp_var_raw (TREE_TYPE (op), "C"); - gimple_add_tmp_var (new_var); - - mod = build2 (INIT_EXPR, TREE_TYPE (new_var), new_var, op); - gimplify_and_add (mod, pre_p); - - TREE_OPERAND (expr, 0) = new_var; - return GS_OK; - } - - return GS_UNHANDLED; - - case DECL_EXPR: - op = DECL_EXPR_DECL (expr); - - /* The expressions for the RM bounds must be gimplified to ensure that - they are properly elaborated. See gimplify_decl_expr. */ - if ((TREE_CODE (op) == TYPE_DECL || TREE_CODE (op) == VAR_DECL) - && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (op))) - switch (TREE_CODE (TREE_TYPE (op))) - { - case INTEGER_TYPE: - case ENUMERAL_TYPE: - case BOOLEAN_TYPE: - case REAL_TYPE: - { - tree type = TYPE_MAIN_VARIANT (TREE_TYPE (op)), t, val; - - val = TYPE_RM_MIN_VALUE (type); - if (val) - { - gimplify_one_sizepos (&val, pre_p); - for (t = type; t; t = TYPE_NEXT_VARIANT (t)) - SET_TYPE_RM_MIN_VALUE (t, val); - } - - val = TYPE_RM_MAX_VALUE (type); - if (val) - { - gimplify_one_sizepos (&val, pre_p); - for (t = type; t; t = TYPE_NEXT_VARIANT (t)) - SET_TYPE_RM_MAX_VALUE (t, val); - } - - } - break; - - default: - break; - } - - /* ... fall through ... */ - - default: - return GS_UNHANDLED; - } -} - -/* Generate GIMPLE in place for the statement at *STMT_P. */ - -static enum gimplify_status -gnat_gimplify_stmt (tree *stmt_p) -{ - tree stmt = *stmt_p; - - switch (TREE_CODE (stmt)) - { - case STMT_STMT: - *stmt_p = STMT_STMT_STMT (stmt); - return GS_OK; - - case LOOP_STMT: - { - tree gnu_start_label = create_artificial_label (input_location); - tree gnu_cond = LOOP_STMT_COND (stmt); - tree gnu_update = LOOP_STMT_UPDATE (stmt); - tree gnu_end_label = LOOP_STMT_LABEL (stmt); - - /* Build the condition expression from the test, if any. */ - if (gnu_cond) - { - /* Deal with the optimization hints. */ - if (LOOP_STMT_IVDEP (stmt)) - gnu_cond = build3 (ANNOTATE_EXPR, TREE_TYPE (gnu_cond), gnu_cond, - build_int_cst (integer_type_node, - annot_expr_ivdep_kind), - integer_zero_node); - if (LOOP_STMT_NO_UNROLL (stmt)) - gnu_cond = build3 (ANNOTATE_EXPR, TREE_TYPE (gnu_cond), gnu_cond, - build_int_cst (integer_type_node, - annot_expr_unroll_kind), - integer_one_node); - if (LOOP_STMT_UNROLL (stmt)) - gnu_cond = build3 (ANNOTATE_EXPR, TREE_TYPE (gnu_cond), gnu_cond, - build_int_cst (integer_type_node, - annot_expr_unroll_kind), - build_int_cst (NULL_TREE, USHRT_MAX)); - if (LOOP_STMT_NO_VECTOR (stmt)) - gnu_cond = build3 (ANNOTATE_EXPR, TREE_TYPE (gnu_cond), gnu_cond, - build_int_cst (integer_type_node, - annot_expr_no_vector_kind), - integer_zero_node); - if (LOOP_STMT_VECTOR (stmt)) - gnu_cond = build3 (ANNOTATE_EXPR, TREE_TYPE (gnu_cond), gnu_cond, - build_int_cst (integer_type_node, - annot_expr_vector_kind), - integer_zero_node); - - gnu_cond - = build3 (COND_EXPR, void_type_node, gnu_cond, NULL_TREE, - build1 (GOTO_EXPR, void_type_node, gnu_end_label)); - } - - /* Set to emit the statements of the loop. */ - *stmt_p = NULL_TREE; - - /* We first emit the start label and then a conditional jump to the - end label if there's a top condition, then the update if it's at - the top, then the body of the loop, then a conditional jump to - the end label if there's a bottom condition, then the update if - it's at the bottom, and finally a jump to the start label and the - definition of the end label. */ - append_to_statement_list (build1 (LABEL_EXPR, void_type_node, - gnu_start_label), - stmt_p); - - if (gnu_cond && !LOOP_STMT_BOTTOM_COND_P (stmt)) - append_to_statement_list (gnu_cond, stmt_p); - - if (gnu_update && LOOP_STMT_TOP_UPDATE_P (stmt)) - append_to_statement_list (gnu_update, stmt_p); - - append_to_statement_list (LOOP_STMT_BODY (stmt), stmt_p); - - if (gnu_cond && LOOP_STMT_BOTTOM_COND_P (stmt)) - append_to_statement_list (gnu_cond, stmt_p); - - if (gnu_update && !LOOP_STMT_TOP_UPDATE_P (stmt)) - append_to_statement_list (gnu_update, stmt_p); - - tree t = build1 (GOTO_EXPR, void_type_node, gnu_start_label); - SET_EXPR_LOCATION (t, DECL_SOURCE_LOCATION (gnu_end_label)); - append_to_statement_list (t, stmt_p); - - append_to_statement_list (build1 (LABEL_EXPR, void_type_node, - gnu_end_label), - stmt_p); - return GS_OK; - } - - case EXIT_STMT: - /* Build a statement to jump to the corresponding end label, then - see if it needs to be conditional. */ - *stmt_p = build1 (GOTO_EXPR, void_type_node, EXIT_STMT_LABEL (stmt)); - if (EXIT_STMT_COND (stmt)) - *stmt_p = build3 (COND_EXPR, void_type_node, - EXIT_STMT_COND (stmt), *stmt_p, alloc_stmt_list ()); - return GS_OK; - - default: - gcc_unreachable (); - } -} - -/* Force a reference to each of the entities in GNAT_PACKAGE recursively. - - This routine is exclusively called in type_annotate mode, to compute DDA - information for types in withed units, for ASIS use. */ - -static void -elaborate_all_entities_for_package (Entity_Id gnat_package) -{ - Entity_Id gnat_entity; - - for (gnat_entity = First_Entity (gnat_package); - Present (gnat_entity); - gnat_entity = Next_Entity (gnat_entity)) - { - const Entity_Kind kind = Ekind (gnat_entity); - - /* We are interested only in entities visible from the main unit. */ - if (!Is_Public (gnat_entity)) - continue; - - /* Skip stuff internal to the compiler. */ - if (Is_Intrinsic_Subprogram (gnat_entity)) - continue; - if (kind == E_Operator) - continue; - if (IN (kind, Subprogram_Kind) - && (Present (Alias (gnat_entity)) - || Is_Intrinsic_Subprogram (gnat_entity))) - continue; - if (Is_Itype (gnat_entity)) - continue; - - /* Skip named numbers. */ - if (IN (kind, Named_Kind)) - continue; - - /* Skip generic declarations. */ - if (IN (kind, Generic_Unit_Kind)) - continue; - - /* Skip formal objects. */ - if (IN (kind, Formal_Object_Kind)) - continue; - - /* Skip package bodies. */ - if (kind == E_Package_Body) - continue; - - /* Skip limited views that point back to the main unit. */ - if (IN (kind, Incomplete_Kind) - && From_Limited_With (gnat_entity) - && In_Extended_Main_Code_Unit (Non_Limited_View (gnat_entity))) - continue; - - /* Skip types that aren't frozen. */ - if (IN (kind, Type_Kind) && !Is_Frozen (gnat_entity)) - continue; - - /* Recurse on real packages that aren't in the main unit. */ - if (kind == E_Package) - { - if (No (Renamed_Entity (gnat_entity)) - && !In_Extended_Main_Code_Unit (gnat_entity)) - elaborate_all_entities_for_package (gnat_entity); - } - else - gnat_to_gnu_entity (gnat_entity, NULL_TREE, false); - } -} - -/* Force a reference to each of the entities in packages withed by GNAT_NODE. - Operate recursively but check that we aren't elaborating something more - than once. - - This routine is exclusively called in type_annotate mode, to compute DDA - information for types in withed units, for ASIS use. */ - -static void -elaborate_all_entities (Node_Id gnat_node) -{ - Entity_Id gnat_with_clause; - - /* Process each unit only once. As we trace the context of all relevant - units transitively, including generic bodies, we may encounter the - same generic unit repeatedly. */ - if (!present_gnu_tree (gnat_node)) - save_gnu_tree (gnat_node, integer_zero_node, true); - - /* Save entities in all context units. A body may have an implicit_with - on its own spec, if the context includes a child unit, so don't save - the spec twice. */ - for (gnat_with_clause = First (Context_Items (gnat_node)); - Present (gnat_with_clause); - gnat_with_clause = Next (gnat_with_clause)) - if (Nkind (gnat_with_clause) == N_With_Clause - && !present_gnu_tree (Library_Unit (gnat_with_clause)) - && Library_Unit (gnat_with_clause) != Library_Unit (Cunit (Main_Unit))) - { - Node_Id gnat_unit = Library_Unit (gnat_with_clause); - Entity_Id gnat_entity = Entity (Name (gnat_with_clause)); - - elaborate_all_entities (gnat_unit); - - if (Ekind (gnat_entity) == E_Package - && No (Renamed_Entity (gnat_entity))) - elaborate_all_entities_for_package (gnat_entity); - - else if (Ekind (gnat_entity) == E_Generic_Package) - { - Node_Id gnat_body = Corresponding_Body (Unit (gnat_unit)); - - /* Retrieve compilation unit node of generic body. */ - while (Present (gnat_body) - && Nkind (gnat_body) != N_Compilation_Unit) - gnat_body = Parent (gnat_body); - - /* If body is available, elaborate its context. */ - if (Present (gnat_body)) - elaborate_all_entities (gnat_body); - } - } - - if (Nkind (Unit (gnat_node)) == N_Package_Body) - elaborate_all_entities (Library_Unit (gnat_node)); -} - -/* Do the processing of GNAT_NODE, an N_Freeze_Entity. */ - -static void -process_freeze_entity (Node_Id gnat_node) -{ - const Entity_Id gnat_entity = Entity (gnat_node); - const Entity_Kind kind = Ekind (gnat_entity); - tree gnu_old, gnu_new; - - /* If this is a package, generate code for the package body, if any. */ - if (kind == E_Package) - { - const Node_Id gnat_decl = Parent (Declaration_Node (gnat_entity)); - if (Present (Corresponding_Body (gnat_decl))) - insert_code_for (Parent (Corresponding_Body (gnat_decl))); - return; - } - - /* Don't do anything for class-wide types as they are always transformed - into their root type. */ - if (kind == E_Class_Wide_Type) - return; - - /* Check for an old definition if this isn't an object with address clause, - since the saved GCC tree is the address expression in that case. */ - gnu_old - = present_gnu_tree (gnat_entity) && No (Address_Clause (gnat_entity)) - ? get_gnu_tree (gnat_entity) : NULL_TREE; - - /* Don't do anything for subprograms that may have been elaborated before - their freeze nodes. This can happen, for example, because of an inner - call in an instance body or because of previous compilation of a spec - for inlining purposes. */ - if (gnu_old - && ((TREE_CODE (gnu_old) == FUNCTION_DECL - && (kind == E_Function || kind == E_Procedure)) - || (FUNC_OR_METHOD_TYPE_P (TREE_TYPE (gnu_old)) - && kind == E_Subprogram_Type))) - return; - - /* If we have a non-dummy type old tree, we have nothing to do, except for - aborting, since this node was never delayed as it should have been. We - let this happen for concurrent types and their Corresponding_Record_Type, - however, because each might legitimately be elaborated before its own - freeze node, e.g. while processing the other. */ - if (gnu_old - && !(TREE_CODE (gnu_old) == TYPE_DECL - && TYPE_IS_DUMMY_P (TREE_TYPE (gnu_old)))) - { - gcc_assert (Is_Concurrent_Type (gnat_entity) - || (Is_Record_Type (gnat_entity) - && Is_Concurrent_Record_Type (gnat_entity))); - return; - } - - /* Reset the saved tree, if any, and elaborate the object or type for real. - If there is a full view, elaborate it and use the result. And, if this - is the root type of a class-wide type, reuse it for the latter. */ - if (gnu_old) - { - save_gnu_tree (gnat_entity, NULL_TREE, false); - - if (Is_Incomplete_Or_Private_Type (gnat_entity) - && Present (Full_View (gnat_entity))) - { - Entity_Id full_view = Full_View (gnat_entity); - - save_gnu_tree (full_view, NULL_TREE, false); - - if (Is_Private_Type (full_view) - && Present (Underlying_Full_View (full_view))) - { - full_view = Underlying_Full_View (full_view); - save_gnu_tree (full_view, NULL_TREE, false); - } - } - - if (Is_Type (gnat_entity) - && Present (Class_Wide_Type (gnat_entity)) - && Root_Type (Class_Wide_Type (gnat_entity)) == gnat_entity) - save_gnu_tree (Class_Wide_Type (gnat_entity), NULL_TREE, false); - } - - if (Is_Incomplete_Or_Private_Type (gnat_entity) - && Present (Full_View (gnat_entity))) - { - Entity_Id full_view = Full_View (gnat_entity); - - if (Is_Private_Type (full_view) - && Present (Underlying_Full_View (full_view))) - full_view = Underlying_Full_View (full_view); - - gnu_new = gnat_to_gnu_entity (full_view, NULL_TREE, true); - - /* Propagate back-annotations from full view to partial view. */ - if (!Known_Alignment (gnat_entity)) - Copy_Alignment (gnat_entity, full_view); - - if (!Known_Esize (gnat_entity)) - Copy_Esize (gnat_entity, full_view); - - if (!Known_RM_Size (gnat_entity)) - Copy_RM_Size (gnat_entity, full_view); - - /* The above call may have defined this entity (the simplest example - of this is when we have a private enumeral type since the bounds - will have the public view). */ - if (!present_gnu_tree (gnat_entity)) - save_gnu_tree (gnat_entity, gnu_new, false); - } - else - { - tree gnu_init - = (Nkind (Declaration_Node (gnat_entity)) == N_Object_Declaration - && present_gnu_tree (Declaration_Node (gnat_entity))) - ? get_gnu_tree (Declaration_Node (gnat_entity)) : NULL_TREE; - - gnu_new = gnat_to_gnu_entity (gnat_entity, gnu_init, true); - } - - if (Is_Type (gnat_entity) - && Present (Class_Wide_Type (gnat_entity)) - && Root_Type (Class_Wide_Type (gnat_entity)) == gnat_entity) - save_gnu_tree (Class_Wide_Type (gnat_entity), gnu_new, false); - - /* If we have an old type and we've made pointers to this type, update those - pointers. If this is a Taft amendment type in the main unit, we need to - mark the type as used since other units referencing it don't see the full - declaration and, therefore, cannot mark it as used themselves. */ - if (gnu_old) - { - update_pointer_to (TYPE_MAIN_VARIANT (TREE_TYPE (gnu_old)), - TREE_TYPE (gnu_new)); - if (TYPE_DUMMY_IN_PROFILE_P (TREE_TYPE (gnu_old))) - update_profiles_with (TREE_TYPE (gnu_old)); - if (DECL_TAFT_TYPE_P (gnu_old)) - used_types_insert (TREE_TYPE (gnu_new)); - } -} - -/* Elaborate decls in the lists GNAT_DECLS and GNAT_DECLS2, if present. - We make two passes, one to elaborate anything other than bodies (but - we declare a function if there was no spec). The second pass - elaborates the bodies. - - GNAT_END_LIST gives the element in the list past the end. Normally, - this is Empty, but can be First_Real_Statement for a - Handled_Sequence_Of_Statements. - - We make a complete pass through both lists if PASS1P is true, then make - the second pass over both lists if PASS2P is true. The lists usually - correspond to the public and private parts of a package. */ - -static void -process_decls (List_Id gnat_decls, List_Id gnat_decls2, - Node_Id gnat_end_list, bool pass1p, bool pass2p) -{ - List_Id gnat_decl_array[2]; - Node_Id gnat_decl; - int i; - - gnat_decl_array[0] = gnat_decls, gnat_decl_array[1] = gnat_decls2; - - if (pass1p) - for (i = 0; i <= 1; i++) - if (Present (gnat_decl_array[i])) - for (gnat_decl = First (gnat_decl_array[i]); - gnat_decl != gnat_end_list; gnat_decl = Next (gnat_decl)) - { - /* For package specs, we recurse inside the declarations, - thus taking the two pass approach inside the boundary. */ - if (Nkind (gnat_decl) == N_Package_Declaration - && (Nkind (Specification (gnat_decl) - == N_Package_Specification))) - process_decls (Visible_Declarations (Specification (gnat_decl)), - Private_Declarations (Specification (gnat_decl)), - Empty, true, false); - - /* Similarly for any declarations in the actions of a - freeze node. */ - else if (Nkind (gnat_decl) == N_Freeze_Entity) - { - process_freeze_entity (gnat_decl); - process_decls (Actions (gnat_decl), Empty, Empty, true, false); - } - - /* Package bodies with freeze nodes get their elaboration deferred - until the freeze node, but the code must be placed in the right - place, so record the code position now. */ - else if (Nkind (gnat_decl) == N_Package_Body - && Present (Freeze_Node (Corresponding_Spec (gnat_decl)))) - record_code_position (gnat_decl); - - else if (Nkind (gnat_decl) == N_Package_Body_Stub - && Present (Library_Unit (gnat_decl)) - && Present (Freeze_Node - (Corresponding_Spec - (Proper_Body (Unit - (Library_Unit (gnat_decl))))))) - record_code_position - (Proper_Body (Unit (Library_Unit (gnat_decl)))); - - /* We defer most subprogram bodies to the second pass. */ - else if (Nkind (gnat_decl) == N_Subprogram_Body) - { - if (Acts_As_Spec (gnat_decl)) - { - Node_Id gnat_subprog_id = Defining_Entity (gnat_decl); - - if (Ekind (gnat_subprog_id) != E_Generic_Procedure - && Ekind (gnat_subprog_id) != E_Generic_Function) - gnat_to_gnu_entity (gnat_subprog_id, NULL_TREE, true); - } - } - - /* For bodies and stubs that act as their own specs, the entity - itself must be elaborated in the first pass, because it may - be used in other declarations. */ - else if (Nkind (gnat_decl) == N_Subprogram_Body_Stub) - { - Node_Id gnat_subprog_id - = Defining_Entity (Specification (gnat_decl)); - - if (Ekind (gnat_subprog_id) != E_Subprogram_Body - && Ekind (gnat_subprog_id) != E_Generic_Procedure - && Ekind (gnat_subprog_id) != E_Generic_Function) - gnat_to_gnu_entity (gnat_subprog_id, NULL_TREE, true); - } - - /* Concurrent stubs stand for the corresponding subprogram bodies, - which are deferred like other bodies. */ - else if (Nkind (gnat_decl) == N_Task_Body_Stub - || Nkind (gnat_decl) == N_Protected_Body_Stub) - ; - - /* Renamed subprograms may not be elaborated yet at this point - since renamings do not trigger freezing. Wait for the second - pass to take care of them. */ - else if (Nkind (gnat_decl) == N_Subprogram_Renaming_Declaration) - ; - - else - add_stmt (gnat_to_gnu (gnat_decl)); - } - - /* Here we elaborate everything we deferred above except for package bodies, - which are elaborated at their freeze nodes. Note that we must also - go inside things (package specs and freeze nodes) the first pass did. */ - if (pass2p) - for (i = 0; i <= 1; i++) - if (Present (gnat_decl_array[i])) - for (gnat_decl = First (gnat_decl_array[i]); - gnat_decl != gnat_end_list; gnat_decl = Next (gnat_decl)) - { - if (Nkind (gnat_decl) == N_Subprogram_Body - || Nkind (gnat_decl) == N_Subprogram_Body_Stub - || Nkind (gnat_decl) == N_Task_Body_Stub - || Nkind (gnat_decl) == N_Protected_Body_Stub) - add_stmt (gnat_to_gnu (gnat_decl)); - - else if (Nkind (gnat_decl) == N_Package_Declaration - && (Nkind (Specification (gnat_decl) - == N_Package_Specification))) - process_decls (Visible_Declarations (Specification (gnat_decl)), - Private_Declarations (Specification (gnat_decl)), - Empty, false, true); - - else if (Nkind (gnat_decl) == N_Freeze_Entity) - process_decls (Actions (gnat_decl), Empty, Empty, false, true); - - else if (Nkind (gnat_decl) == N_Subprogram_Renaming_Declaration) - add_stmt (gnat_to_gnu (gnat_decl)); - } -} - -/* Make a unary operation of kind CODE using build_unary_op, but guard - the operation by an overflow check. CODE can be one of NEGATE_EXPR - or ABS_EXPR. GNU_TYPE is the type desired for the result. Usually - the operation is to be performed in that type. GNAT_NODE is the gnat - node conveying the source location for which the error should be - signaled. */ - -static tree -build_unary_op_trapv (enum tree_code code, tree gnu_type, tree operand, - Node_Id gnat_node) -{ - gcc_assert (code == NEGATE_EXPR || code == ABS_EXPR); - - operand = gnat_protect_expr (operand); - - return emit_check (build_binary_op (EQ_EXPR, boolean_type_node, - operand, TYPE_MIN_VALUE (gnu_type)), - build_unary_op (code, gnu_type, operand), - CE_Overflow_Check_Failed, gnat_node); -} - -/* Make a binary operation of kind CODE using build_binary_op, but guard - the operation by an overflow check. CODE can be one of PLUS_EXPR, - MINUS_EXPR or MULT_EXPR. GNU_TYPE is the type desired for the result. - Usually the operation is to be performed in that type. GNAT_NODE is - the GNAT node conveying the source location for which the error should - be signaled. */ - -static tree -build_binary_op_trapv (enum tree_code code, tree gnu_type, tree left, - tree right, Node_Id gnat_node) -{ - const unsigned int precision = TYPE_PRECISION (gnu_type); - tree lhs = gnat_protect_expr (left); - tree rhs = gnat_protect_expr (right); - tree type_max = TYPE_MAX_VALUE (gnu_type); - tree type_min = TYPE_MIN_VALUE (gnu_type); - tree gnu_expr, check; - int sgn; - - /* Assert that the precision is a power of 2. */ - gcc_assert ((precision & (precision - 1)) == 0); - - /* Prefer a constant on the RHS to simplify checks. */ - if (TREE_CODE (rhs) != INTEGER_CST - && TREE_CODE (lhs) == INTEGER_CST - && (code == PLUS_EXPR || code == MULT_EXPR)) - { - tree tmp = lhs; - lhs = rhs; - rhs = tmp; - } - - gnu_expr = build_binary_op (code, gnu_type, lhs, rhs); - - /* If we can fold the expression to a constant, just return it. - The caller will deal with overflow, no need to generate a check. */ - if (TREE_CODE (gnu_expr) == INTEGER_CST) - return gnu_expr; - - /* If no operand is a constant, we use the generic implementation. */ - if (TREE_CODE (lhs) != INTEGER_CST && TREE_CODE (rhs) != INTEGER_CST) - { - /* First convert the operands to the result type like build_binary_op. - This is where the bias is made explicit for biased types. */ - lhs = convert (gnu_type, lhs); - rhs = convert (gnu_type, rhs); - - /* Never inline a 64-bit mult for a 32-bit target, it's way too long. */ - if (code == MULT_EXPR && precision == 64 && BITS_PER_WORD < 64) - { - tree int64 = gnat_type_for_size (64, 0); - return convert (gnu_type, build_call_n_expr (mulv64_decl, 2, - convert (int64, lhs), - convert (int64, rhs))); - } - - /* Likewise for a 128-bit mult and a 64-bit target. */ - else if (code == MULT_EXPR && precision == 128 && BITS_PER_WORD < 128) - { - tree int128 = gnat_type_for_size (128, 0); - return convert (gnu_type, build_call_n_expr (mulv128_decl, 2, - convert (int128, lhs), - convert (int128, rhs))); - } - - enum internal_fn icode; - - switch (code) - { - case PLUS_EXPR: - icode = IFN_ADD_OVERFLOW; - break; - case MINUS_EXPR: - icode = IFN_SUB_OVERFLOW; - break; - case MULT_EXPR: - icode = IFN_MUL_OVERFLOW; - break; - default: - gcc_unreachable (); - } - - tree gnu_ctype = build_complex_type (gnu_type); - tree call - = build_call_expr_internal_loc (UNKNOWN_LOCATION, icode, gnu_ctype, 2, - lhs, rhs); - tree tgt = save_expr (call); - gnu_expr = build1 (REALPART_EXPR, gnu_type, tgt); - check = fold_build2 (NE_EXPR, boolean_type_node, - build1 (IMAGPART_EXPR, gnu_type, tgt), - build_int_cst (gnu_type, 0)); - return - emit_check (check, gnu_expr, CE_Overflow_Check_Failed, gnat_node); - } - - /* If one operand is a constant, we expose the overflow condition to enable - a subsequent simplication or even elimination. */ - switch (code) - { - case PLUS_EXPR: - sgn = tree_int_cst_sgn (rhs); - if (sgn > 0) - /* When rhs > 0, overflow when lhs > type_max - rhs. */ - check = build_binary_op (GT_EXPR, boolean_type_node, lhs, - build_binary_op (MINUS_EXPR, gnu_type, - type_max, rhs)); - else if (sgn < 0) - /* When rhs < 0, overflow when lhs < type_min - rhs. */ - check = build_binary_op (LT_EXPR, boolean_type_node, lhs, - build_binary_op (MINUS_EXPR, gnu_type, - type_min, rhs)); - else - return gnu_expr; - break; - - case MINUS_EXPR: - if (TREE_CODE (lhs) == INTEGER_CST) - { - sgn = tree_int_cst_sgn (lhs); - if (sgn > 0) - /* When lhs > 0, overflow when rhs < lhs - type_max. */ - check = build_binary_op (LT_EXPR, boolean_type_node, rhs, - build_binary_op (MINUS_EXPR, gnu_type, - lhs, type_max)); - else if (sgn < 0) - /* When lhs < 0, overflow when rhs > lhs - type_min. */ - check = build_binary_op (GT_EXPR, boolean_type_node, rhs, - build_binary_op (MINUS_EXPR, gnu_type, - lhs, type_min)); - else - return gnu_expr; - } - else - { - sgn = tree_int_cst_sgn (rhs); - if (sgn > 0) - /* When rhs > 0, overflow when lhs < type_min + rhs. */ - check = build_binary_op (LT_EXPR, boolean_type_node, lhs, - build_binary_op (PLUS_EXPR, gnu_type, - type_min, rhs)); - else if (sgn < 0) - /* When rhs < 0, overflow when lhs > type_max + rhs. */ - check = build_binary_op (GT_EXPR, boolean_type_node, lhs, - build_binary_op (PLUS_EXPR, gnu_type, - type_max, rhs)); - else - return gnu_expr; - } - break; - - case MULT_EXPR: - sgn = tree_int_cst_sgn (rhs); - if (sgn > 0) - { - if (integer_onep (rhs)) - return gnu_expr; - - tree lb = build_binary_op (TRUNC_DIV_EXPR, gnu_type, type_min, rhs); - tree ub = build_binary_op (TRUNC_DIV_EXPR, gnu_type, type_max, rhs); - - /* When rhs > 1, overflow outside [type_min/rhs; type_max/rhs]. */ - check - = build_binary_op (TRUTH_ORIF_EXPR, boolean_type_node, - build_binary_op (LT_EXPR, boolean_type_node, - lhs, lb), - build_binary_op (GT_EXPR, boolean_type_node, - lhs, ub)); - } - else if (sgn < 0) - { - tree lb = build_binary_op (TRUNC_DIV_EXPR, gnu_type, type_max, rhs); - tree ub = build_binary_op (TRUNC_DIV_EXPR, gnu_type, type_min, rhs); - - if (integer_minus_onep (rhs)) - /* When rhs == -1, overflow if lhs == type_min. */ - check - = build_binary_op (EQ_EXPR, boolean_type_node, lhs, type_min); - else - /* When rhs < -1, overflow outside [type_max/rhs; type_min/rhs]. */ - check - = build_binary_op (TRUTH_ORIF_EXPR, boolean_type_node, - build_binary_op (LT_EXPR, boolean_type_node, - lhs, lb), - build_binary_op (GT_EXPR, boolean_type_node, - lhs, ub)); - } - else - return gnu_expr; - break; - - default: - gcc_unreachable (); - } - - return emit_check (check, gnu_expr, CE_Overflow_Check_Failed, gnat_node); -} - -/* GNU_COND contains the condition corresponding to an index, overflow or - range check of value GNU_EXPR. Build a COND_EXPR that returns GNU_EXPR - if GNU_COND is false and raises a CONSTRAINT_ERROR if GNU_COND is true. - REASON is the code that says why the exception is raised. GNAT_NODE is - the node conveying the source location for which the error should be - signaled. - - We used to propagate TREE_SIDE_EFFECTS from GNU_EXPR to the COND_EXPR, - overwriting the setting inherited from the call statement, on the ground - that the expression need not be evaluated just for the check. However - that's incorrect because, in the GCC type system, its value is presumed - to be valid so its comparison against the type bounds always yields true - and, therefore, could be done without evaluating it; given that it can - be a computation that overflows the bounds, the language may require the - check to fail and thus the expression to be evaluated in this case. */ - -static tree -emit_check (tree gnu_cond, tree gnu_expr, int reason, Node_Id gnat_node) -{ - tree gnu_call - = build_call_raise (reason, gnat_node, N_Raise_Constraint_Error); - return - fold_build3 (COND_EXPR, TREE_TYPE (gnu_expr), gnu_cond, - build2 (COMPOUND_EXPR, TREE_TYPE (gnu_expr), gnu_call, - SCALAR_FLOAT_TYPE_P (TREE_TYPE (gnu_expr)) - ? build_real (TREE_TYPE (gnu_expr), dconst0) - : build_int_cst (TREE_TYPE (gnu_expr), 0)), - gnu_expr); -} - -/* Return an expression that converts GNU_EXPR to GNAT_TYPE, doing overflow - checks if OVERFLOW_P is true. If TRUNCATE_P is true, do a fp-to-integer - conversion with truncation, otherwise round. GNAT_NODE is the GNAT node - conveying the source location for which the error should be signaled. */ - -static tree -convert_with_check (Entity_Id gnat_type, tree gnu_expr, bool overflow_p, - bool truncate_p, Node_Id gnat_node) -{ - tree gnu_type = get_unpadded_type (gnat_type); - tree gnu_base_type = get_base_type (gnu_type); - tree gnu_in_type = TREE_TYPE (gnu_expr); - tree gnu_in_base_type = get_base_type (gnu_in_type); - tree gnu_result = gnu_expr; - - /* If we are not doing any checks, the output is an integral type and the - input is not a floating-point type, just do the conversion. This is - required for packed array types and is simpler in all cases anyway. */ - if (!overflow_p - && INTEGRAL_TYPE_P (gnu_base_type) - && !FLOAT_TYPE_P (gnu_in_base_type)) - return convert (gnu_type, gnu_expr); - - /* If the mode of the input base type is larger, then converting to it below - may pessimize the final conversion step, for example generate a libcall - instead of a simple instruction, so use a narrower type in this case. */ - if (TYPE_MODE (gnu_in_base_type) != TYPE_MODE (gnu_in_type) - && !(TREE_CODE (gnu_in_type) == INTEGER_TYPE - && TYPE_BIASED_REPRESENTATION_P (gnu_in_type))) - gnu_in_base_type = gnat_type_for_mode (TYPE_MODE (gnu_in_type), - TYPE_UNSIGNED (gnu_in_type)); - - /* First convert the expression to the base type. This will never generate - code, but makes the tests below simpler. But don't do this if converting - from an integer type to an unconstrained array type since then we need to - get the bounds from the original (unpacked) type. */ - if (TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE) - gnu_result = convert (gnu_in_base_type, gnu_result); - - /* If overflow checks are requested, we need to be sure the result will fit - in the output base type. But don't do this if the input is integer and - the output floating-point. */ - if (overflow_p - && !(FLOAT_TYPE_P (gnu_base_type) && INTEGRAL_TYPE_P (gnu_in_base_type))) - { - /* Ensure GNU_EXPR only gets evaluated once. */ - tree gnu_input = gnat_protect_expr (gnu_result); - tree gnu_cond = boolean_false_node; - tree gnu_in_lb = TYPE_MIN_VALUE (gnu_in_base_type); - tree gnu_in_ub = TYPE_MAX_VALUE (gnu_in_base_type); - tree gnu_out_lb = TYPE_MIN_VALUE (gnu_base_type); - tree gnu_out_ub - = (TREE_CODE (gnu_base_type) == INTEGER_TYPE - && TYPE_MODULAR_P (gnu_base_type)) - ? fold_build2 (MINUS_EXPR, gnu_base_type, - TYPE_MODULUS (gnu_base_type), - build_int_cst (gnu_base_type, 1)) - : TYPE_MAX_VALUE (gnu_base_type); - - /* Convert the lower bounds to signed types, so we're sure we're - comparing them properly. Likewise, convert the upper bounds - to unsigned types. */ - if (INTEGRAL_TYPE_P (gnu_in_base_type) - && TYPE_UNSIGNED (gnu_in_base_type)) - gnu_in_lb - = convert (gnat_signed_type_for (gnu_in_base_type), gnu_in_lb); - - if (INTEGRAL_TYPE_P (gnu_in_base_type) - && !TYPE_UNSIGNED (gnu_in_base_type)) - gnu_in_ub - = convert (gnat_unsigned_type_for (gnu_in_base_type), gnu_in_ub); - - if (INTEGRAL_TYPE_P (gnu_base_type) && TYPE_UNSIGNED (gnu_base_type)) - gnu_out_lb - = convert (gnat_signed_type_for (gnu_base_type), gnu_out_lb); - - if (INTEGRAL_TYPE_P (gnu_base_type) && !TYPE_UNSIGNED (gnu_base_type)) - gnu_out_ub - = convert (gnat_unsigned_type_for (gnu_base_type), gnu_out_ub); - - /* Check each bound separately and only if the result bound - is tighter than the bound on the input type. Note that all the - types are base types, so the bounds must be constant. Also, - the comparison is done in the base type of the input, which - always has the proper signedness. First check for input - integer (which means output integer), output float (which means - both float), or mixed, in which case we always compare. - Note that we have to do the comparison which would *fail* in the - case of an error since if it's an FP comparison and one of the - values is a NaN or Inf, the comparison will fail. */ - if (INTEGRAL_TYPE_P (gnu_in_base_type) - ? tree_int_cst_lt (gnu_in_lb, gnu_out_lb) - : (FLOAT_TYPE_P (gnu_base_type) - ? real_less (&TREE_REAL_CST (gnu_in_lb), - &TREE_REAL_CST (gnu_out_lb)) - : 1)) - gnu_cond - = invert_truthvalue - (build_binary_op (GE_EXPR, boolean_type_node, - gnu_input, convert (gnu_in_base_type, - gnu_out_lb))); - - if (INTEGRAL_TYPE_P (gnu_in_base_type) - ? tree_int_cst_lt (gnu_out_ub, gnu_in_ub) - : (FLOAT_TYPE_P (gnu_base_type) - ? real_less (&TREE_REAL_CST (gnu_out_ub), - &TREE_REAL_CST (gnu_in_ub)) - : 1)) - gnu_cond - = build_binary_op (TRUTH_ORIF_EXPR, boolean_type_node, gnu_cond, - invert_truthvalue - (build_binary_op (LE_EXPR, boolean_type_node, - gnu_input, - convert (gnu_in_base_type, - gnu_out_ub)))); - - if (!integer_zerop (gnu_cond)) - gnu_result = emit_check (gnu_cond, gnu_input, - CE_Overflow_Check_Failed, gnat_node); - } - - /* Now convert to the result base type. If this is a non-truncating - float-to-integer conversion, round. */ - if (INTEGRAL_TYPE_P (gnu_base_type) - && FLOAT_TYPE_P (gnu_in_base_type) - && !truncate_p) - { - REAL_VALUE_TYPE half_minus_pred_half, pred_half; - tree gnu_conv, gnu_zero, gnu_comp, calc_type; - tree gnu_pred_half, gnu_add_pred_half, gnu_subtract_pred_half; - const struct real_format *fmt; - - /* The following calculations depend on proper rounding to even - of each arithmetic operation. In order to prevent excess - precision from spoiling this property, use the widest hardware - floating-point type if FP_ARITH_MAY_WIDEN is true. */ - calc_type - = fp_arith_may_widen ? longest_float_type_node : gnu_in_base_type; - - /* Compute the exact value calc_type'Pred (0.5) at compile time. */ - fmt = REAL_MODE_FORMAT (TYPE_MODE (calc_type)); - real_2expN (&half_minus_pred_half, -(fmt->p) - 1, TYPE_MODE (calc_type)); - real_arithmetic (&pred_half, MINUS_EXPR, &dconsthalf, - &half_minus_pred_half); - gnu_pred_half = build_real (calc_type, pred_half); - - /* If the input is strictly negative, subtract this value - and otherwise add it from the input. For 0.5, the result - is exactly between 1.0 and the machine number preceding 1.0 - (for calc_type). Since the last bit of 1.0 is even, this 0.5 - will round to 1.0, while all other number with an absolute - value less than 0.5 round to 0.0. For larger numbers exactly - halfway between integers, rounding will always be correct as - the true mathematical result will be closer to the higher - integer compared to the lower one. So, this constant works - for all floating-point numbers. - - The reason to use the same constant with subtract/add instead - of a positive and negative constant is to allow the comparison - to be scheduled in parallel with retrieval of the constant and - conversion of the input to the calc_type (if necessary). */ - - gnu_zero = build_real (gnu_in_base_type, dconst0); - gnu_result = gnat_protect_expr (gnu_result); - gnu_conv = convert (calc_type, gnu_result); - gnu_comp - = fold_build2 (GE_EXPR, boolean_type_node, gnu_result, gnu_zero); - gnu_add_pred_half - = fold_build2 (PLUS_EXPR, calc_type, gnu_conv, gnu_pred_half); - gnu_subtract_pred_half - = fold_build2 (MINUS_EXPR, calc_type, gnu_conv, gnu_pred_half); - gnu_result = fold_build3 (COND_EXPR, calc_type, gnu_comp, - gnu_add_pred_half, gnu_subtract_pred_half); - } - - if (TREE_CODE (gnu_base_type) == INTEGER_TYPE - && TYPE_HAS_ACTUAL_BOUNDS_P (gnu_base_type) - && TREE_CODE (gnu_result) == UNCONSTRAINED_ARRAY_REF) - gnu_result = unchecked_convert (gnu_base_type, gnu_result, false); - else - gnu_result = convert (gnu_base_type, gnu_result); - - return convert (gnu_type, gnu_result); -} - -/* Return true if GNU_EXPR can be directly addressed. This is the case - unless it is an expression involving computation or if it involves a - reference to a bitfield or to an object not sufficiently aligned for - its type. If GNU_TYPE is non-null, return true only if GNU_EXPR can - be directly addressed as an object of this type. - - *** Notes on addressability issues in the Ada compiler *** - - This predicate is necessary in order to bridge the gap between Gigi - and the middle-end about addressability of GENERIC trees. A tree - is said to be addressable if it can be directly addressed, i.e. if - its address can be taken, is a multiple of the type's alignment on - strict-alignment architectures and returns the first storage unit - assigned to the object represented by the tree. - - In the C family of languages, everything is in practice addressable - at the language level, except for bit-fields. This means that these - compilers will take the address of any tree that doesn't represent - a bit-field reference and expect the result to be the first storage - unit assigned to the object. Even in cases where this will result - in unaligned accesses at run time, nothing is supposed to be done - and the program is considered as erroneous instead (see PR c/18287). - - The implicit assumptions made in the middle-end are in keeping with - the C viewpoint described above: - - the address of a bit-field reference is supposed to be never - taken; the compiler (generally) will stop on such a construct, - - any other tree is addressable if it is formally addressable, - i.e. if it is formally allowed to be the operand of ADDR_EXPR. - - In Ada, the viewpoint is the opposite one: nothing is addressable - at the language level unless explicitly declared so. This means - that the compiler will both make sure that the trees representing - references to addressable ("aliased" in Ada parlance) objects are - addressable and make no real attempts at ensuring that the trees - representing references to non-addressable objects are addressable. - - In the first case, Ada is effectively equivalent to C and handing - down the direct result of applying ADDR_EXPR to these trees to the - middle-end works flawlessly. In the second case, Ada cannot afford - to consider the program as erroneous if the address of trees that - are not addressable is requested for technical reasons, unlike C; - as a consequence, the Ada compiler must arrange for either making - sure that this address is not requested in the middle-end or for - compensating by inserting temporaries if it is requested in Gigi. - - The first goal can be achieved because the middle-end should not - request the address of non-addressable trees on its own; the only - exception is for the invocation of low-level block operations like - memcpy, for which the addressability requirements are lower since - the type's alignment can be disregarded. In practice, this means - that Gigi must make sure that such operations cannot be applied to - non-BLKmode bit-fields. - - The second goal is achieved by means of the addressable_p predicate, - which computes whether a temporary must be inserted by Gigi when the - address of a tree is requested; if so, the address of the temporary - will be used in lieu of that of the original tree and some glue code - generated to connect everything together. */ - -static bool -addressable_p (tree gnu_expr, tree gnu_type) -{ - /* For an integral type, the size of the actual type of the object may not - be greater than that of the expected type, otherwise an indirect access - in the latter type wouldn't correctly set all the bits of the object. */ - if (gnu_type - && INTEGRAL_TYPE_P (gnu_type) - && smaller_form_type_p (gnu_type, TREE_TYPE (gnu_expr))) - return false; - - /* The size of the actual type of the object may not be smaller than that - of the expected type, otherwise an indirect access in the latter type - would be larger than the object. But only record types need to be - considered in practice for this case. */ - if (gnu_type - && TREE_CODE (gnu_type) == RECORD_TYPE - && smaller_form_type_p (TREE_TYPE (gnu_expr), gnu_type)) - return false; - - switch (TREE_CODE (gnu_expr)) - { - case VAR_DECL: - case PARM_DECL: - case FUNCTION_DECL: - case RESULT_DECL: - /* All DECLs are addressable: if they are in a register, we can force - them to memory. */ - return true; - - case UNCONSTRAINED_ARRAY_REF: - case INDIRECT_REF: - /* Taking the address of a dereference yields the original pointer. */ - return true; - - case STRING_CST: - case INTEGER_CST: - case REAL_CST: - /* Taking the address yields a pointer to the constant pool. */ - return true; - - case CONSTRUCTOR: - /* Taking the address of a static constructor yields a pointer to the - tree constant pool. */ - return TREE_STATIC (gnu_expr) ? true : false; - - case NULL_EXPR: - case ADDR_EXPR: - case SAVE_EXPR: - case CALL_EXPR: - case PLUS_EXPR: - case MINUS_EXPR: - case BIT_IOR_EXPR: - case BIT_XOR_EXPR: - case BIT_AND_EXPR: - case BIT_NOT_EXPR: - /* All rvalues are deemed addressable since taking their address will - force a temporary to be created by the middle-end. */ - return true; - - case COMPOUND_EXPR: - /* The address of a compound expression is that of its 2nd operand. */ - return addressable_p (TREE_OPERAND (gnu_expr, 1), gnu_type); - - case COND_EXPR: - /* We accept &COND_EXPR as soon as both operands are addressable and - expect the outcome to be the address of the selected operand. */ - return (addressable_p (TREE_OPERAND (gnu_expr, 1), NULL_TREE) - && addressable_p (TREE_OPERAND (gnu_expr, 2), NULL_TREE)); - - case COMPONENT_REF: - return (((!DECL_BIT_FIELD (TREE_OPERAND (gnu_expr, 1)) - /* Even with DECL_BIT_FIELD cleared, we have to ensure that - the field is sufficiently aligned, in case it is subject - to a pragma Component_Alignment. But we don't need to - check the alignment of the containing record, as it is - guaranteed to be not smaller than that of its most - aligned field that is not a bit-field. */ - && (!STRICT_ALIGNMENT - || DECL_ALIGN (TREE_OPERAND (gnu_expr, 1)) - >= TYPE_ALIGN (TREE_TYPE (gnu_expr)))) - /* The field of a padding record is always addressable. */ - || TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))) - && addressable_p (TREE_OPERAND (gnu_expr, 0), NULL_TREE)); - - case ARRAY_REF: case ARRAY_RANGE_REF: - case REALPART_EXPR: case IMAGPART_EXPR: - case NOP_EXPR: - return addressable_p (TREE_OPERAND (gnu_expr, 0), NULL_TREE); - - case CONVERT_EXPR: - return (AGGREGATE_TYPE_P (TREE_TYPE (gnu_expr)) - && addressable_p (TREE_OPERAND (gnu_expr, 0), NULL_TREE)); - - case VIEW_CONVERT_EXPR: - { - /* This is addressable if we can avoid a copy. */ - tree type = TREE_TYPE (gnu_expr); - tree inner_type = TREE_TYPE (TREE_OPERAND (gnu_expr, 0)); - return (((TYPE_MODE (type) == TYPE_MODE (inner_type) - && (!STRICT_ALIGNMENT - || TYPE_ALIGN (type) <= TYPE_ALIGN (inner_type) - || TYPE_ALIGN (inner_type) >= BIGGEST_ALIGNMENT)) - || ((TYPE_MODE (type) == BLKmode - || TYPE_MODE (inner_type) == BLKmode) - && (!STRICT_ALIGNMENT - || TYPE_ALIGN (type) <= TYPE_ALIGN (inner_type) - || TYPE_ALIGN (inner_type) >= BIGGEST_ALIGNMENT - || TYPE_ALIGN_OK (type) - || TYPE_ALIGN_OK (inner_type)))) - && addressable_p (TREE_OPERAND (gnu_expr, 0), NULL_TREE)); - } - - default: - return false; - } -} - -/* Do the processing for the declaration of a GNAT_ENTITY, a type or subtype. - If a Freeze node exists for the entity, delay the bulk of the processing. - Otherwise make a GCC type for GNAT_ENTITY and set up the correspondence. */ - -void -process_type (Entity_Id gnat_entity) -{ - tree gnu_old - = present_gnu_tree (gnat_entity) ? get_gnu_tree (gnat_entity) : NULL_TREE; - - /* If we are to delay elaboration of this type, just do any elaboration - needed for expressions within the declaration and make a dummy node - for it and its Full_View (if any), in case something points to it. - Do not do this if it has already been done (the only way that can - happen is if the private completion is also delayed). */ - if (Present (Freeze_Node (gnat_entity))) - { - elaborate_entity (gnat_entity); - - if (!gnu_old) - { - tree gnu_decl = TYPE_STUB_DECL (make_dummy_type (gnat_entity)); - save_gnu_tree (gnat_entity, gnu_decl, false); - if (Is_Incomplete_Or_Private_Type (gnat_entity) - && Present (Full_View (gnat_entity))) - { - if (Has_Completion_In_Body (gnat_entity)) - DECL_TAFT_TYPE_P (gnu_decl) = 1; - save_gnu_tree (Full_View (gnat_entity), gnu_decl, false); - } - } - - return; - } - - /* If we saved away a dummy type for this node, it means that this made the - type that corresponds to the full type of an incomplete type. Clear that - type for now and then update the type in the pointers below. But, if the - saved type is not dummy, it very likely means that we have a use before - declaration for the type in the tree, what we really cannot handle. */ - if (gnu_old) - { - gcc_assert (TREE_CODE (gnu_old) == TYPE_DECL - && TYPE_IS_DUMMY_P (TREE_TYPE (gnu_old))); - - save_gnu_tree (gnat_entity, NULL_TREE, false); - } - - /* Now fully elaborate the type. */ - tree gnu_new = gnat_to_gnu_entity (gnat_entity, NULL_TREE, true); - gcc_assert (TREE_CODE (gnu_new) == TYPE_DECL); - - /* If we have an old type and we've made pointers to this type, update those - pointers. If this is a Taft amendment type in the main unit, we need to - mark the type as used since other units referencing it don't see the full - declaration and, therefore, cannot mark it as used themselves. */ - if (gnu_old) - { - update_pointer_to (TYPE_MAIN_VARIANT (TREE_TYPE (gnu_old)), - TREE_TYPE (gnu_new)); - if (DECL_TAFT_TYPE_P (gnu_old)) - used_types_insert (TREE_TYPE (gnu_new)); - } - - /* If this is a record type corresponding to a task or protected type - that is a completion of an incomplete type, perform a similar update - on the type. ??? Including protected types here is a guess. */ - if (Is_Record_Type (gnat_entity) - && Is_Concurrent_Record_Type (gnat_entity) - && present_gnu_tree (Corresponding_Concurrent_Type (gnat_entity))) - { - tree gnu_task_old - = get_gnu_tree (Corresponding_Concurrent_Type (gnat_entity)); - - save_gnu_tree (Corresponding_Concurrent_Type (gnat_entity), - NULL_TREE, false); - save_gnu_tree (Corresponding_Concurrent_Type (gnat_entity), - gnu_new, false); - - update_pointer_to (TYPE_MAIN_VARIANT (TREE_TYPE (gnu_task_old)), - TREE_TYPE (gnu_new)); - } -} - -/* Subroutine of assoc_to_constructor: VALUES is a list of field associations, - some of which are from RECORD_TYPE. Return a CONSTRUCTOR consisting of the - associations that are from RECORD_TYPE. If we see an internal record, make - a recursive call to fill it in as well. */ - -static tree -extract_values (tree values, tree record_type) -{ - vec<constructor_elt, va_gc> *v = NULL; - tree field; - - for (field = TYPE_FIELDS (record_type); field; field = DECL_CHAIN (field)) - { - tree tem, value = NULL_TREE; - - /* _Parent is an internal field, but may have values in the aggregate, - so check for values first. */ - if ((tem = purpose_member (field, values))) - { - value = TREE_VALUE (tem); - TREE_ADDRESSABLE (tem) = 1; - } - - else if (DECL_INTERNAL_P (field)) - { - value = extract_values (values, TREE_TYPE (field)); - if (TREE_CODE (value) == CONSTRUCTOR - && vec_safe_is_empty (CONSTRUCTOR_ELTS (value))) - value = NULL_TREE; - } - else - /* If we have a record subtype, the names will match, but not the - actual FIELD_DECLs. */ - for (tem = values; tem; tem = TREE_CHAIN (tem)) - if (DECL_NAME (TREE_PURPOSE (tem)) == DECL_NAME (field)) - { - value = convert (TREE_TYPE (field), TREE_VALUE (tem)); - TREE_ADDRESSABLE (tem) = 1; - } - - if (!value) - continue; - - CONSTRUCTOR_APPEND_ELT (v, field, value); - } - - return gnat_build_constructor (record_type, v); -} - -/* GNAT_ENTITY is the type of the resulting constructor, GNAT_ASSOC is the - front of the Component_Associations of an N_Aggregate and GNU_TYPE is the - GCC type of the corresponding record type. Return the CONSTRUCTOR. */ - -static tree -assoc_to_constructor (Entity_Id gnat_entity, Node_Id gnat_assoc, tree gnu_type) -{ - tree gnu_list = NULL_TREE, gnu_result; - - /* We test for GNU_FIELD being empty in the case where a variant - was the last thing since we don't take things off GNAT_ASSOC in - that case. We check GNAT_ASSOC in case we have a variant, but it - has no fields. */ - - for (; Present (gnat_assoc); gnat_assoc = Next (gnat_assoc)) - { - const Node_Id gnat_field = First (Choices (gnat_assoc)); - const Node_Id gnat_expr = Expression (gnat_assoc); - tree gnu_field = gnat_to_gnu_field_decl (Entity (gnat_field)); - tree gnu_expr = gnat_to_gnu (Expression (gnat_assoc)); - - /* The expander is supposed to put a single component selector name - in every record component association. */ - gcc_assert (No (Next (gnat_field))); - - /* Ignore discriminants that have Corresponding_Discriminants in tagged - types since we'll be setting those fields in the parent subtype. */ - if (Ekind (Entity (gnat_field)) == E_Discriminant - && Present (Corresponding_Discriminant (Entity (gnat_field))) - && Is_Tagged_Type (Scope (Entity (gnat_field)))) - continue; - - /* Also ignore discriminants of Unchecked_Unions. */ - if (Ekind (Entity (gnat_field)) == E_Discriminant - && Is_Unchecked_Union (gnat_entity)) - continue; - - gigi_checking_assert (!Do_Range_Check (gnat_expr)); - - /* Convert to the type of the field. */ - gnu_expr = convert (TREE_TYPE (gnu_field), gnu_expr); - - /* Add the field and expression to the list. */ - gnu_list = tree_cons (gnu_field, gnu_expr, gnu_list); - } - - gnu_result = extract_values (gnu_list, gnu_type); - - if (flag_checking) - { - /* Verify that every entry in GNU_LIST was used. */ - for (; gnu_list; gnu_list = TREE_CHAIN (gnu_list)) - gcc_assert (TREE_ADDRESSABLE (gnu_list)); - } - - return gnu_result; -} - -/* Build a possibly nested constructor for array aggregates. GNAT_EXPR is - the first element of an array aggregate. It may itself be an aggregate. - GNU_ARRAY_TYPE is the GCC type corresponding to the array aggregate. */ - -static tree -pos_to_constructor (Node_Id gnat_expr, tree gnu_array_type) -{ - tree gnu_index = TYPE_MIN_VALUE (TYPE_DOMAIN (gnu_array_type)); - vec<constructor_elt, va_gc> *gnu_expr_vec = NULL; - - for (; Present (gnat_expr); gnat_expr = Next (gnat_expr)) - { - tree gnu_expr; - - /* If the expression is itself an array aggregate then first build the - innermost constructor if it is part of our array (multi-dimensional - case). */ - if (Nkind (gnat_expr) == N_Aggregate - && TREE_CODE (TREE_TYPE (gnu_array_type)) == ARRAY_TYPE - && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_array_type))) - gnu_expr = pos_to_constructor (First (Expressions (gnat_expr)), - TREE_TYPE (gnu_array_type)); - else - { - /* If the expression is a conversion to an unconstrained array type, - skip it to avoid spilling to memory. */ - if (Nkind (gnat_expr) == N_Type_Conversion - && Is_Array_Type (Etype (gnat_expr)) - && !Is_Constrained (Etype (gnat_expr))) - gnu_expr = gnat_to_gnu (Expression (gnat_expr)); - else - gnu_expr = gnat_to_gnu (gnat_expr); - - gigi_checking_assert (!Do_Range_Check (gnat_expr)); - } - - CONSTRUCTOR_APPEND_ELT (gnu_expr_vec, gnu_index, - convert (TREE_TYPE (gnu_array_type), gnu_expr)); - - gnu_index = int_const_binop (PLUS_EXPR, gnu_index, - convert (TREE_TYPE (gnu_index), - integer_one_node)); - } - - return gnat_build_constructor (gnu_array_type, gnu_expr_vec); -} - -/* Process a N_Validate_Unchecked_Conversion node. */ - -static void -validate_unchecked_conversion (Node_Id gnat_node) -{ - tree gnu_source_type = gnat_to_gnu_type (Source_Type (gnat_node)); - tree gnu_target_type = gnat_to_gnu_type (Target_Type (gnat_node)); - - /* If the target is a pointer type, see if we are either converting from a - non-pointer or from a pointer to a type with a different alias set and - warn if so, unless the pointer has been marked to alias everything. */ - if (POINTER_TYPE_P (gnu_target_type) - && !TYPE_REF_CAN_ALIAS_ALL (gnu_target_type)) - { - tree gnu_source_desig_type = POINTER_TYPE_P (gnu_source_type) - ? TREE_TYPE (gnu_source_type) - : NULL_TREE; - tree gnu_target_desig_type = TREE_TYPE (gnu_target_type); - alias_set_type target_alias_set = get_alias_set (gnu_target_desig_type); - - if (target_alias_set != 0 - && (!POINTER_TYPE_P (gnu_source_type) - || !alias_sets_conflict_p (get_alias_set (gnu_source_desig_type), - target_alias_set))) - { - post_error_ne ("??possible aliasing problem for type&", - gnat_node, Target_Type (gnat_node)); - post_error ("\\?use -fno-strict-aliasing switch for references", - gnat_node); - post_error_ne ("\\?or use `pragma No_Strict_Aliasing (&);`", - gnat_node, Target_Type (gnat_node)); - } - } - - /* Likewise if the target is a fat pointer type, but we have no mechanism to - mitigate the problem in this case, so we unconditionally warn. */ - else if (TYPE_IS_FAT_POINTER_P (gnu_target_type)) - { - tree gnu_source_desig_type - = TYPE_IS_FAT_POINTER_P (gnu_source_type) - ? TREE_TYPE (TREE_TYPE (TYPE_FIELDS (gnu_source_type))) - : NULL_TREE; - tree gnu_target_desig_type - = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (gnu_target_type))); - alias_set_type target_alias_set = get_alias_set (gnu_target_desig_type); - - if (target_alias_set != 0 - && (!TYPE_IS_FAT_POINTER_P (gnu_source_type) - || !alias_sets_conflict_p (get_alias_set (gnu_source_desig_type), - target_alias_set))) - { - post_error_ne ("??possible aliasing problem for type&", - gnat_node, Target_Type (gnat_node)); - post_error ("\\?use -fno-strict-aliasing switch for references", - gnat_node); - } - } -} - -/* Convert SLOC into LOCUS. Return true if SLOC corresponds to a - source code location and false if it doesn't. If CLEAR_COLUMN is - true, set the column information to 0. If DECL is given and SLOC - refers to a File with an instance, map DECL to that instance. */ - -bool -Sloc_to_locus (Source_Ptr Sloc, location_t *locus, bool clear_column, - const_tree decl) -{ - if (Sloc == No_Location) - return false; - - if (Sloc <= Standard_Location) - { - *locus = BUILTINS_LOCATION; - return false; - } - - Source_File_Index file = Get_Source_File_Index (Sloc); - Line_Number_Type line = Get_Logical_Line_Number (Sloc); - Column_Number_Type column = (clear_column ? 0 : Get_Column_Number (Sloc)); - line_map_ordinary *map = LINEMAPS_ORDINARY_MAP_AT (line_table, file - 1); - - /* We can have zero if pragma Source_Reference is in effect. */ - if (line < 1) - line = 1; - - /* Translate the location. */ - *locus - = linemap_position_for_line_and_column (line_table, map, line, column); - - if (file_map && file_map[file - 1].Instance) - decl_to_instance_map->put (decl, file_map[file - 1].Instance); - - return true; -} - -/* Return whether GNAT_NODE is a defining identifier for a renaming that comes - from the parameter association for the instantiation of a generic. We do - not want to emit source location for them: the code generated for their - initialization is likely to disturb debugging. */ - -bool -renaming_from_instantiation_p (Node_Id gnat_node) -{ - if (Nkind (gnat_node) != N_Defining_Identifier - || !Is_Object (gnat_node) - || Comes_From_Source (gnat_node) - || !Present (Renamed_Object (gnat_node))) - return false; - - /* Get the object declaration of the renamed object, if any and if the - renamed object is a mere identifier. */ - gnat_node = Renamed_Object (gnat_node); - if (Nkind (gnat_node) != N_Identifier) - return false; - - gnat_node = Parent (Entity (gnat_node)); - return (Present (gnat_node) - && Nkind (gnat_node) == N_Object_Declaration - && Present (Corresponding_Generic_Association (gnat_node))); -} - -/* Similar to set_expr_location, but start with the Sloc of GNAT_NODE and - don't do anything if it doesn't correspond to a source location. And, - if CLEAR_COLUMN is true, set the column information to 0. */ - -static void -set_expr_location_from_node (tree node, Node_Id gnat_node, bool clear_column) -{ - location_t locus; - - /* Do not set a location for constructs likely to disturb debugging. */ - if (Nkind (gnat_node) == N_Defining_Identifier) - { - if (Is_Type (gnat_node) && Is_Actual_Subtype (gnat_node)) - return; - - if (renaming_from_instantiation_p (gnat_node)) - return; - } - - if (!Sloc_to_locus (Sloc (gnat_node), &locus, clear_column)) - return; - - SET_EXPR_LOCATION (node, locus); -} - -/* More elaborate version of set_expr_location_from_node to be used in more - general contexts, for example the result of the translation of a generic - GNAT node. */ - -static void -set_gnu_expr_location_from_node (tree node, Node_Id gnat_node) -{ - /* Set the location information on the node if it is a real expression. - References can be reused for multiple GNAT nodes and they would get - the location information of their last use. Also make sure not to - overwrite an existing location as it is probably more precise. */ - - switch (TREE_CODE (node)) - { - CASE_CONVERT: - case NON_LVALUE_EXPR: - case SAVE_EXPR: - break; - - case COMPOUND_EXPR: - if (EXPR_P (TREE_OPERAND (node, 1))) - set_gnu_expr_location_from_node (TREE_OPERAND (node, 1), gnat_node); - - /* ... fall through ... */ - - default: - if (!REFERENCE_CLASS_P (node) && !EXPR_HAS_LOCATION (node)) - { - set_expr_location_from_node (node, gnat_node); - set_end_locus_from_node (node, gnat_node); - } - break; - } -} - -/* Set the end_locus information for GNU_NODE, if any, from an explicit end - location associated with GNAT_NODE or GNAT_NODE itself, whichever makes - most sense. Return true if a sensible assignment was performed. */ - -static bool -set_end_locus_from_node (tree gnu_node, Node_Id gnat_node) -{ - Node_Id gnat_end_label; - location_t end_locus; - - /* Pick the GNAT node of which we'll take the sloc to assign to the GCC node - end_locus when there is one. We consider only GNAT nodes with a possible - End_Label attached. If the End_Label actually was unassigned, fallback - on the original node. We'd better assign an explicit sloc associated with - the outer construct in any case. */ - - switch (Nkind (gnat_node)) - { - case N_Package_Body: - case N_Subprogram_Body: - case N_Block_Statement: - if (Present (Handled_Statement_Sequence (gnat_node))) - gnat_end_label = End_Label (Handled_Statement_Sequence (gnat_node)); - else - gnat_end_label = Empty; - - break; - - case N_Package_Declaration: - gcc_checking_assert (Present (Specification (gnat_node))); - gnat_end_label = End_Label (Specification (gnat_node)); - break; - - default: - return false; - } - - if (Present (gnat_end_label)) - gnat_node = gnat_end_label; - - /* Some expanded subprograms have neither an End_Label nor a Sloc - attached. Notify that to callers. For a block statement with no - End_Label, clear column information, so that the tree for a - transient block does not receive the sloc of a source condition. */ - if (!Sloc_to_locus (Sloc (gnat_node), &end_locus, - No (gnat_end_label) - && (Nkind (gnat_node) == N_Block_Statement))) - return false; - - switch (TREE_CODE (gnu_node)) - { - case BIND_EXPR: - BLOCK_SOURCE_END_LOCATION (BIND_EXPR_BLOCK (gnu_node)) = end_locus; - return true; - - case FUNCTION_DECL: - DECL_STRUCT_FUNCTION (gnu_node)->function_end_locus = end_locus; - return true; - - default: - return false; - } -} - -/* Post an error message. MSG is the error message, properly annotated. - NODE is the node at which to post the error and the node to use for the - '&' substitution. */ - -void -post_error (const char *msg, Node_Id node) -{ - String_Template temp; - String_Pointer sp; - - if (No (node)) - return; - - temp.Low_Bound = 1; - temp.High_Bound = strlen (msg); - sp.Bounds = &temp; - sp.Array = msg; - Error_Msg_N (sp, node); -} - -/* Similar to post_error, but NODE is the node at which to post the error and - ENT is the node to use for the '&' substitution. */ - -void -post_error_ne (const char *msg, Node_Id node, Entity_Id ent) -{ - String_Template temp; - String_Pointer sp; - - if (No (node)) - return; - - temp.Low_Bound = 1; - temp.High_Bound = strlen (msg); - sp.Bounds = &temp; - sp.Array = msg; - Error_Msg_NE (sp, node, ent); -} - -/* Similar to post_error_ne, but NUM is the number to use for the '^'. */ - -void -post_error_ne_num (const char *msg, Node_Id node, Entity_Id ent, int num) -{ - Error_Msg_Uint_1 = UI_From_Int (num); - post_error_ne (msg, node, ent); -} - -/* Similar to post_error_ne, but T is a GCC tree representing the number to - write. If T represents a constant, the text inside curly brackets in - MSG will be output (presumably including a '^'). Otherwise it will not - be output and the text inside square brackets will be output instead. */ - -void -post_error_ne_tree (const char *msg, Node_Id node, Entity_Id ent, tree t) -{ - char *new_msg = XALLOCAVEC (char, strlen (msg) + 1); - char start_yes, end_yes, start_no, end_no; - const char *p; - char *q; - - if (TREE_CODE (t) == INTEGER_CST) - { - Error_Msg_Uint_1 = UI_From_gnu (t); - start_yes = '{', end_yes = '}', start_no = '[', end_no = ']'; - } - else - start_yes = '[', end_yes = ']', start_no = '{', end_no = '}'; - - for (p = msg, q = new_msg; *p; p++) - { - if (*p == start_yes) - for (p++; *p != end_yes; p++) - *q++ = *p; - else if (*p == start_no) - for (p++; *p != end_no; p++) - ; - else - *q++ = *p; - } - - *q = 0; - - post_error_ne (new_msg, node, ent); -} - -/* Similar to post_error_ne_tree, but NUM is a second integer to write. */ - -void -post_error_ne_tree_2 (const char *msg, Node_Id node, Entity_Id ent, tree t, - int num) -{ - Error_Msg_Uint_2 = UI_From_Int (num); - post_error_ne_tree (msg, node, ent, t); -} - -/* Return a label to branch to for the exception type in KIND or Empty - if none. */ - -Entity_Id -get_exception_label (char kind) -{ - switch (kind) - { - case N_Raise_Constraint_Error: - return gnu_constraint_error_label_stack.last (); - - case N_Raise_Storage_Error: - return gnu_storage_error_label_stack.last (); - - case N_Raise_Program_Error: - return gnu_program_error_label_stack.last (); - - default: - return Empty; - } - - gcc_unreachable (); -} - -/* Return the decl for the current elaboration procedure. */ - -static tree -get_elaboration_procedure (void) -{ - return gnu_elab_proc_stack->last (); -} - -/* Return the controlling type of a dispatching subprogram. */ - -static Entity_Id -get_controlling_type (Entity_Id subprog) -{ - /* This is modeled on Expand_Interface_Thunk. */ - Entity_Id controlling_type = Etype (First_Formal (subprog)); - if (Is_Access_Type (controlling_type)) - controlling_type = Directly_Designated_Type (controlling_type); - controlling_type = Underlying_Type (controlling_type); - if (Is_Concurrent_Type (controlling_type)) - controlling_type = Corresponding_Record_Type (controlling_type); - controlling_type = Base_Type (controlling_type); - return controlling_type; -} - -/* Return whether we should use an alias for the TARGET of a thunk - in order to make the call generated in the thunk local. */ - -static bool -use_alias_for_thunk_p (tree target) -{ - /* We cannot generate a local call in this case. */ - if (DECL_EXTERNAL (target)) - return false; - - /* The call is already local in this case. */ - if (TREE_CODE (DECL_CONTEXT (target)) == FUNCTION_DECL) - return false; - - return TARGET_USE_LOCAL_THUNK_ALIAS_P (target); -} - -static GTY(()) unsigned long thunk_labelno = 0; - -/* Create an alias for TARGET to be used as the target of a thunk. */ - -static tree -make_alias_for_thunk (tree target) -{ - char buf[64]; - targetm.asm_out.generate_internal_label (buf, "LTHUNK", thunk_labelno++); - - tree alias = build_decl (DECL_SOURCE_LOCATION (target), TREE_CODE (target), - get_identifier (buf), TREE_TYPE (target)); - - DECL_LANG_SPECIFIC (alias) = DECL_LANG_SPECIFIC (target); - DECL_CONTEXT (alias) = DECL_CONTEXT (target); - TREE_READONLY (alias) = TREE_READONLY (target); - TREE_THIS_VOLATILE (alias) = TREE_THIS_VOLATILE (target); - DECL_ARTIFICIAL (alias) = 1; - DECL_INITIAL (alias) = error_mark_node; - DECL_ARGUMENTS (alias) = copy_list (DECL_ARGUMENTS (target)); - TREE_ADDRESSABLE (alias) = 1; - SET_DECL_ASSEMBLER_NAME (alias, DECL_NAME (alias)); - - cgraph_node *n = cgraph_node::create_same_body_alias (alias, target); - gcc_assert (n); - - return alias; -} - -/* Create the local covariant part of {GNAT,GNU}_THUNK. */ - -static tree -make_covariant_thunk (Entity_Id gnat_thunk, tree gnu_thunk) -{ - tree gnu_name = create_concat_name (gnat_thunk, "CV"); - tree gnu_cv_thunk - = build_decl (DECL_SOURCE_LOCATION (gnu_thunk), TREE_CODE (gnu_thunk), - gnu_name, TREE_TYPE (gnu_thunk)); - - DECL_ARGUMENTS (gnu_cv_thunk) = copy_list (DECL_ARGUMENTS (gnu_thunk)); - for (tree param_decl = DECL_ARGUMENTS (gnu_cv_thunk); - param_decl; - param_decl = DECL_CHAIN (param_decl)) - DECL_CONTEXT (param_decl) = gnu_cv_thunk; - - DECL_RESULT (gnu_cv_thunk) = copy_node (DECL_RESULT (gnu_thunk)); - DECL_CONTEXT (DECL_RESULT (gnu_cv_thunk)) = gnu_cv_thunk; - - DECL_LANG_SPECIFIC (gnu_cv_thunk) = DECL_LANG_SPECIFIC (gnu_thunk); - DECL_CONTEXT (gnu_cv_thunk) = DECL_CONTEXT (gnu_thunk); - TREE_READONLY (gnu_cv_thunk) = TREE_READONLY (gnu_thunk); - TREE_THIS_VOLATILE (gnu_cv_thunk) = TREE_THIS_VOLATILE (gnu_thunk); - DECL_ARTIFICIAL (gnu_cv_thunk) = 1; - - return gnu_cv_thunk; -} - -/* Try to create a GNU thunk for {GNAT,GNU}_THUNK and return true on success. - - GNU thunks are more efficient than GNAT thunks because they don't call into - the runtime to retrieve the offset used in the displacement operation, but - they are tailored to C++ and thus too limited to support the full range of - thunks generated in Ada. Here's the complete list of limitations: - - 1. Multi-controlling thunks, i.e thunks with more than one controlling - parameter, are simply not supported. - - 2. Covariant thunks, i.e. thunks for which the result is also controlling, - are split into a pair of (this, covariant-only) thunks. - - 3. Variable-offset thunks, i.e. thunks for which the offset depends on the - object and not only on its type, are supported as 2nd class citizens. - - 4. External thunks, i.e. thunks for which the target is not declared in - the same unit as the thunk, are supported as 2nd class citizens. - - 5. Local thunks, i.e. thunks generated for a local type, are supported as - 2nd class citizens. */ - -static bool -maybe_make_gnu_thunk (Entity_Id gnat_thunk, tree gnu_thunk) -{ - const Entity_Id gnat_target = Thunk_Entity (gnat_thunk); - - /* Check that the first formal of the target is the only controlling one. */ - Entity_Id gnat_formal = First_Formal (gnat_target); - if (!Is_Controlling_Formal (gnat_formal)) - return false; - for (gnat_formal = Next_Formal (gnat_formal); - Present (gnat_formal); - gnat_formal = Next_Formal (gnat_formal)) - if (Is_Controlling_Formal (gnat_formal)) - return false; - - /* Look for the types that control the target and the thunk. */ - const Entity_Id gnat_controlling_type = get_controlling_type (gnat_target); - const Entity_Id gnat_interface_type = get_controlling_type (gnat_thunk); - - /* We must have an interface type at this point. */ - gcc_assert (Is_Interface (gnat_interface_type)); - - /* Now compute whether the former covers the latter. */ - const Entity_Id gnat_interface_tag - = Find_Interface_Tag (gnat_controlling_type, gnat_interface_type); - tree gnu_interface_tag - = Present (gnat_interface_tag) - ? gnat_to_gnu_field_decl (gnat_interface_tag) - : NULL_TREE; - tree gnu_interface_offset - = gnu_interface_tag ? byte_position (gnu_interface_tag) : NULL_TREE; - - /* There are three ways to retrieve the offset between the interface view - and the base object. Either the controlling type covers the interface - type and the offset of the corresponding tag is fixed, in which case it - can be statically encoded in the thunk (see FIXED_OFFSET below). Or the - controlling type doesn't cover the interface type but is of fixed size, - in which case the offset is stored in the dispatch table, two pointers - above the dispatch table address (see VIRTUAL_VALUE below). Otherwise, - the offset is variable and is stored right after the tag in every object - (see INDIRECT_OFFSET below). See also a-tags.ads for more details. */ - HOST_WIDE_INT fixed_offset, virtual_value, indirect_offset; - tree virtual_offset; - - if (gnu_interface_offset && TREE_CODE (gnu_interface_offset) == INTEGER_CST) - { - fixed_offset = - tree_to_shwi (gnu_interface_offset); - virtual_value = 0; - virtual_offset = NULL_TREE; - indirect_offset = 0; - } - else if (!gnu_interface_offset - && !Is_Variable_Size_Record (gnat_controlling_type)) - { - fixed_offset = 0; - virtual_value = - 2 * (HOST_WIDE_INT) (POINTER_SIZE / BITS_PER_UNIT); - virtual_offset = build_int_cst (integer_type_node, virtual_value); - indirect_offset = 0; - } - else - { - /* Covariant thunks with variable offset are not supported. */ - if (Has_Controlling_Result (gnat_target)) - return false; - - fixed_offset = 0; - virtual_value = 0; - virtual_offset = NULL_TREE; - indirect_offset = (HOST_WIDE_INT) (POINTER_SIZE / BITS_PER_UNIT); - } - - tree gnu_target = gnat_to_gnu_entity (gnat_target, NULL_TREE, false); - - /* If the target is local, then thunk and target must have the same context - because cgraph_node::expand_thunk can only forward the static chain. */ - if (DECL_STATIC_CHAIN (gnu_target) - && DECL_CONTEXT (gnu_thunk) != DECL_CONTEXT (gnu_target)) - return false; - - /* If the target returns by invisible reference and is external, apply the - same transformation as Subprogram_Body_to_gnu here. */ - if (TREE_ADDRESSABLE (TREE_TYPE (gnu_target)) - && DECL_EXTERNAL (gnu_target) - && !POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (gnu_target)))) - { - TREE_TYPE (DECL_RESULT (gnu_target)) - = build_reference_type (TREE_TYPE (DECL_RESULT (gnu_target))); - relayout_decl (DECL_RESULT (gnu_target)); - } - - /* The thunk expander requires the return types of thunk and target to be - compatible, which is not fully the case with the CICO mechanism. */ - if (TYPE_CI_CO_LIST (TREE_TYPE (gnu_thunk))) - { - tree gnu_target_type = TREE_TYPE (gnu_target); - gcc_assert (TYPE_CI_CO_LIST (gnu_target_type)); - TYPE_CANONICAL (TREE_TYPE (TREE_TYPE (gnu_thunk))) - = TYPE_CANONICAL (TREE_TYPE (gnu_target_type)); - } - - cgraph_node *target_node = cgraph_node::get_create (gnu_target); - - /* We may also need to create an alias for the target in order to make - the call local, depending on the linkage of the target. */ - tree gnu_alias = use_alias_for_thunk_p (gnu_target) - ? make_alias_for_thunk (gnu_target) - : gnu_target; - - /* If the return type of the target is a controlling type, then we need - both an usual this thunk and a covariant thunk in this order: - - this thunk --> covariant thunk --> target - - For covariant thunks, we can only handle a fixed offset. */ - if (Has_Controlling_Result (gnat_target)) - { - gcc_assert (fixed_offset < 0); - tree gnu_cv_thunk = make_covariant_thunk (gnat_thunk, gnu_thunk); - target_node->create_thunk (gnu_cv_thunk, gnu_target, false, - - fixed_offset, 0, 0, - NULL_TREE, gnu_alias); - - gnu_alias = gnu_target = gnu_cv_thunk; - } - - target_node->create_thunk (gnu_thunk, gnu_target, true, - fixed_offset, virtual_value, indirect_offset, - virtual_offset, gnu_alias); - - return true; -} - -/* Initialize the table that maps GNAT codes to GCC codes for simple - binary and unary operations. */ - -static void -init_code_table (void) -{ - gnu_codes[N_Op_And] = TRUTH_AND_EXPR; - gnu_codes[N_Op_Or] = TRUTH_OR_EXPR; - gnu_codes[N_Op_Xor] = TRUTH_XOR_EXPR; - gnu_codes[N_Op_Eq] = EQ_EXPR; - gnu_codes[N_Op_Ne] = NE_EXPR; - gnu_codes[N_Op_Lt] = LT_EXPR; - gnu_codes[N_Op_Le] = LE_EXPR; - gnu_codes[N_Op_Gt] = GT_EXPR; - gnu_codes[N_Op_Ge] = GE_EXPR; - gnu_codes[N_Op_Add] = PLUS_EXPR; - gnu_codes[N_Op_Subtract] = MINUS_EXPR; - gnu_codes[N_Op_Multiply] = MULT_EXPR; - gnu_codes[N_Op_Mod] = FLOOR_MOD_EXPR; - gnu_codes[N_Op_Rem] = TRUNC_MOD_EXPR; - gnu_codes[N_Op_Minus] = NEGATE_EXPR; - gnu_codes[N_Op_Abs] = ABS_EXPR; - gnu_codes[N_Op_Not] = TRUTH_NOT_EXPR; - gnu_codes[N_Op_Rotate_Left] = LROTATE_EXPR; - gnu_codes[N_Op_Rotate_Right] = RROTATE_EXPR; - gnu_codes[N_Op_Shift_Left] = LSHIFT_EXPR; - gnu_codes[N_Op_Shift_Right] = RSHIFT_EXPR; - gnu_codes[N_Op_Shift_Right_Arithmetic] = RSHIFT_EXPR; - gnu_codes[N_And_Then] = TRUTH_ANDIF_EXPR; - gnu_codes[N_Or_Else] = TRUTH_ORIF_EXPR; -} - -#include "gt-ada-trans.h" |