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author | Andrew MacLeod <amacleod@redhat.com> | 2013-11-05 19:26:07 +0000 |
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committer | Andrew Macleod <amacleod@gcc.gnu.org> | 2013-11-05 19:26:07 +0000 |
commit | 2a0603f1899262a11e21aba32da9a94d6f1129c3 (patch) | |
tree | 37108019bb346797ef0336eb829491d4143b53c6 /gcc/gimple-expr.c | |
parent | c180e49596bb20aef9c887cf9817e21a7f1e0d2b (diff) | |
download | gcc-2a0603f1899262a11e21aba32da9a94d6f1129c3.zip gcc-2a0603f1899262a11e21aba32da9a94d6f1129c3.tar.gz gcc-2a0603f1899262a11e21aba32da9a94d6f1129c3.tar.bz2 |
gimple.h: Move some prototypes to gimple-expr.h and add to include list.
* gimple.h: Move some prototypes to gimple-expr.h and add to include
list.
(extract_ops_from_tree, gimple_call_addr_fndecl, is_gimple_reg_type):
Move to gimple-expr.h.
* gimple-expr.h: New file. Relocate some prototypes from gimple.h.
(types_compatible_p, is_gimple_reg_type, is_gimple_variable,
is_gimple_id, virtual_operand_p, is_gimple_addressable,
is_gimple_constant, extract_ops_from_tree, gimple_call_addr_fndecl):
Relocate here.
* gimple.c (extract_ops_from_tree_1, gimple_cond_get_ops_from_tree,
gimple_set_body, gimple_body, gimple_has_body_p, is_gimple_lvalue,
is_gimple_condexpr, is_gimple_addressable, is_gimple_constant,
is_gimple_address, is_gimple_invariant_address,
is_gimple_ip_invariant_address, is_gimple_min_invariant,
is_gimple_ip_invariant, is_gimple_variable, is_gimple_id,
virtual_operand_p, is_gimple_reg, is_gimple_val, is_gimple_asm_val,
is_gimple_min_lval, is_gimple_call_addr, is_gimple_mem_ref_addr,
gimple_decl_printable_name, useless_type_conversion_p,
types_compatible_p, gimple_can_coalesce_p, copy_var_decl): Move to
gimple-expr.[ch].
* gimple-expr.c: New File.
(useless_type_conversion_p, gimple_set_body, gimple_body,
gimple_has_body_p, gimple_decl_printable_name, copy_var_decl,
gimple_can_coalesce_p, extract_ops_from_tree_1,
gimple_cond_get_ops_from_tree, is_gimple_lvalue, is_gimple_condexpr,
is_gimple_address, is_gimple_invariant_address,
is_gimple_ip_invariant_address, is_gimple_min_invariant,
is_gimple_ip_invariant, is_gimple_reg, is_gimple_val,
is_gimple_asm_val, is_gimple_min_lval, is_gimple_call_addr,
is_gimple_mem_ref_addr): Relocate here.
* Makefile.in (OBJS): Add gimple-expr.o.
From-SVN: r204412
Diffstat (limited to 'gcc/gimple-expr.c')
-rw-r--r-- | gcc/gimple-expr.c | 721 |
1 files changed, 721 insertions, 0 deletions
diff --git a/gcc/gimple-expr.c b/gcc/gimple-expr.c new file mode 100644 index 0000000..c74d929 --- /dev/null +++ b/gcc/gimple-expr.c @@ -0,0 +1,721 @@ +/* Gimple decl, type, and expression support functions. + + Copyright (C) 2007-2013 Free Software Foundation, Inc. + Contributed by Aldy Hernandez <aldyh@redhat.com> + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 3, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT 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 +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "gimple.h" +#include "demangle.h" + +/* ----- Type related ----- */ + +/* Return true if the conversion from INNER_TYPE to OUTER_TYPE is a + useless type conversion, otherwise return false. + + This function implicitly defines the middle-end type system. With + the notion of 'a < b' meaning that useless_type_conversion_p (a, b) + holds and 'a > b' meaning that useless_type_conversion_p (b, a) holds, + the following invariants shall be fulfilled: + + 1) useless_type_conversion_p is transitive. + If a < b and b < c then a < c. + + 2) useless_type_conversion_p is not symmetric. + From a < b does not follow a > b. + + 3) Types define the available set of operations applicable to values. + A type conversion is useless if the operations for the target type + is a subset of the operations for the source type. For example + casts to void* are useless, casts from void* are not (void* can't + be dereferenced or offsetted, but copied, hence its set of operations + is a strict subset of that of all other data pointer types). Casts + to const T* are useless (can't be written to), casts from const T* + to T* are not. */ + +bool +useless_type_conversion_p (tree outer_type, tree inner_type) +{ + /* Do the following before stripping toplevel qualifiers. */ + if (POINTER_TYPE_P (inner_type) + && POINTER_TYPE_P (outer_type)) + { + /* Do not lose casts between pointers to different address spaces. */ + if (TYPE_ADDR_SPACE (TREE_TYPE (outer_type)) + != TYPE_ADDR_SPACE (TREE_TYPE (inner_type))) + return false; + } + + /* From now on qualifiers on value types do not matter. */ + inner_type = TYPE_MAIN_VARIANT (inner_type); + outer_type = TYPE_MAIN_VARIANT (outer_type); + + if (inner_type == outer_type) + return true; + + /* If we know the canonical types, compare them. */ + if (TYPE_CANONICAL (inner_type) + && TYPE_CANONICAL (inner_type) == TYPE_CANONICAL (outer_type)) + return true; + + /* Changes in machine mode are never useless conversions unless we + deal with aggregate types in which case we defer to later checks. */ + if (TYPE_MODE (inner_type) != TYPE_MODE (outer_type) + && !AGGREGATE_TYPE_P (inner_type)) + return false; + + /* If both the inner and outer types are integral types, then the + conversion is not necessary if they have the same mode and + signedness and precision, and both or neither are boolean. */ + if (INTEGRAL_TYPE_P (inner_type) + && INTEGRAL_TYPE_P (outer_type)) + { + /* Preserve changes in signedness or precision. */ + if (TYPE_UNSIGNED (inner_type) != TYPE_UNSIGNED (outer_type) + || TYPE_PRECISION (inner_type) != TYPE_PRECISION (outer_type)) + return false; + + /* Preserve conversions to/from BOOLEAN_TYPE if types are not + of precision one. */ + if (((TREE_CODE (inner_type) == BOOLEAN_TYPE) + != (TREE_CODE (outer_type) == BOOLEAN_TYPE)) + && TYPE_PRECISION (outer_type) != 1) + return false; + + /* We don't need to preserve changes in the types minimum or + maximum value in general as these do not generate code + unless the types precisions are different. */ + return true; + } + + /* Scalar floating point types with the same mode are compatible. */ + else if (SCALAR_FLOAT_TYPE_P (inner_type) + && SCALAR_FLOAT_TYPE_P (outer_type)) + return true; + + /* Fixed point types with the same mode are compatible. */ + else if (FIXED_POINT_TYPE_P (inner_type) + && FIXED_POINT_TYPE_P (outer_type)) + return true; + + /* We need to take special care recursing to pointed-to types. */ + else if (POINTER_TYPE_P (inner_type) + && POINTER_TYPE_P (outer_type)) + { + /* Do not lose casts to function pointer types. */ + if ((TREE_CODE (TREE_TYPE (outer_type)) == FUNCTION_TYPE + || TREE_CODE (TREE_TYPE (outer_type)) == METHOD_TYPE) + && !(TREE_CODE (TREE_TYPE (inner_type)) == FUNCTION_TYPE + || TREE_CODE (TREE_TYPE (inner_type)) == METHOD_TYPE)) + return false; + + /* We do not care for const qualification of the pointed-to types + as const qualification has no semantic value to the middle-end. */ + + /* Otherwise pointers/references are equivalent. */ + return true; + } + + /* Recurse for complex types. */ + else if (TREE_CODE (inner_type) == COMPLEX_TYPE + && TREE_CODE (outer_type) == COMPLEX_TYPE) + return useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); + + /* Recurse for vector types with the same number of subparts. */ + else if (TREE_CODE (inner_type) == VECTOR_TYPE + && TREE_CODE (outer_type) == VECTOR_TYPE + && TYPE_PRECISION (inner_type) == TYPE_PRECISION (outer_type)) + return useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); + + else if (TREE_CODE (inner_type) == ARRAY_TYPE + && TREE_CODE (outer_type) == ARRAY_TYPE) + { + /* Preserve string attributes. */ + if (TYPE_STRING_FLAG (inner_type) != TYPE_STRING_FLAG (outer_type)) + return false; + + /* Conversions from array types with unknown extent to + array types with known extent are not useless. */ + if (!TYPE_DOMAIN (inner_type) + && TYPE_DOMAIN (outer_type)) + return false; + + /* Nor are conversions from array types with non-constant size to + array types with constant size or to different size. */ + if (TYPE_SIZE (outer_type) + && TREE_CODE (TYPE_SIZE (outer_type)) == INTEGER_CST + && (!TYPE_SIZE (inner_type) + || TREE_CODE (TYPE_SIZE (inner_type)) != INTEGER_CST + || !tree_int_cst_equal (TYPE_SIZE (outer_type), + TYPE_SIZE (inner_type)))) + return false; + + /* Check conversions between arrays with partially known extents. + If the array min/max values are constant they have to match. + Otherwise allow conversions to unknown and variable extents. + In particular this declares conversions that may change the + mode to BLKmode as useless. */ + if (TYPE_DOMAIN (inner_type) + && TYPE_DOMAIN (outer_type) + && TYPE_DOMAIN (inner_type) != TYPE_DOMAIN (outer_type)) + { + tree inner_min = TYPE_MIN_VALUE (TYPE_DOMAIN (inner_type)); + tree outer_min = TYPE_MIN_VALUE (TYPE_DOMAIN (outer_type)); + tree inner_max = TYPE_MAX_VALUE (TYPE_DOMAIN (inner_type)); + tree outer_max = TYPE_MAX_VALUE (TYPE_DOMAIN (outer_type)); + + /* After gimplification a variable min/max value carries no + additional information compared to a NULL value. All that + matters has been lowered to be part of the IL. */ + if (inner_min && TREE_CODE (inner_min) != INTEGER_CST) + inner_min = NULL_TREE; + if (outer_min && TREE_CODE (outer_min) != INTEGER_CST) + outer_min = NULL_TREE; + if (inner_max && TREE_CODE (inner_max) != INTEGER_CST) + inner_max = NULL_TREE; + if (outer_max && TREE_CODE (outer_max) != INTEGER_CST) + outer_max = NULL_TREE; + + /* Conversions NULL / variable <- cst are useless, but not + the other way around. */ + if (outer_min + && (!inner_min + || !tree_int_cst_equal (inner_min, outer_min))) + return false; + if (outer_max + && (!inner_max + || !tree_int_cst_equal (inner_max, outer_max))) + return false; + } + + /* Recurse on the element check. */ + return useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_type)); + } + + else if ((TREE_CODE (inner_type) == FUNCTION_TYPE + || TREE_CODE (inner_type) == METHOD_TYPE) + && TREE_CODE (inner_type) == TREE_CODE (outer_type)) + { + tree outer_parm, inner_parm; + + /* If the return types are not compatible bail out. */ + if (!useless_type_conversion_p (TREE_TYPE (outer_type), + TREE_TYPE (inner_type))) + return false; + + /* Method types should belong to a compatible base class. */ + if (TREE_CODE (inner_type) == METHOD_TYPE + && !useless_type_conversion_p (TYPE_METHOD_BASETYPE (outer_type), + TYPE_METHOD_BASETYPE (inner_type))) + return false; + + /* A conversion to an unprototyped argument list is ok. */ + if (!prototype_p (outer_type)) + return true; + + /* If the unqualified argument types are compatible the conversion + is useless. */ + if (TYPE_ARG_TYPES (outer_type) == TYPE_ARG_TYPES (inner_type)) + return true; + + for (outer_parm = TYPE_ARG_TYPES (outer_type), + inner_parm = TYPE_ARG_TYPES (inner_type); + outer_parm && inner_parm; + outer_parm = TREE_CHAIN (outer_parm), + inner_parm = TREE_CHAIN (inner_parm)) + if (!useless_type_conversion_p + (TYPE_MAIN_VARIANT (TREE_VALUE (outer_parm)), + TYPE_MAIN_VARIANT (TREE_VALUE (inner_parm)))) + return false; + + /* If there is a mismatch in the number of arguments the functions + are not compatible. */ + if (outer_parm || inner_parm) + return false; + + /* Defer to the target if necessary. */ + if (TYPE_ATTRIBUTES (inner_type) || TYPE_ATTRIBUTES (outer_type)) + return comp_type_attributes (outer_type, inner_type) != 0; + + return true; + } + + /* For aggregates we rely on TYPE_CANONICAL exclusively and require + explicit conversions for types involving to be structurally + compared types. */ + else if (AGGREGATE_TYPE_P (inner_type) + && TREE_CODE (inner_type) == TREE_CODE (outer_type)) + return false; + + return false; +} + + +/* ----- Decl related ----- */ + +/* Set sequence SEQ to be the GIMPLE body for function FN. */ + +void +gimple_set_body (tree fndecl, gimple_seq seq) +{ + struct function *fn = DECL_STRUCT_FUNCTION (fndecl); + if (fn == NULL) + { + /* If FNDECL still does not have a function structure associated + with it, then it does not make sense for it to receive a + GIMPLE body. */ + gcc_assert (seq == NULL); + } + else + fn->gimple_body = seq; +} + + +/* Return the body of GIMPLE statements for function FN. After the + CFG pass, the function body doesn't exist anymore because it has + been split up into basic blocks. In this case, it returns + NULL. */ + +gimple_seq +gimple_body (tree fndecl) +{ + struct function *fn = DECL_STRUCT_FUNCTION (fndecl); + return fn ? fn->gimple_body : NULL; +} + +/* Return true when FNDECL has Gimple body either in unlowered + or CFG form. */ +bool +gimple_has_body_p (tree fndecl) +{ + struct function *fn = DECL_STRUCT_FUNCTION (fndecl); + return (gimple_body (fndecl) || (fn && fn->cfg)); +} + +/* Return a printable name for symbol DECL. */ + +const char * +gimple_decl_printable_name (tree decl, int verbosity) +{ + if (!DECL_NAME (decl)) + return NULL; + + if (DECL_ASSEMBLER_NAME_SET_P (decl)) + { + const char *str, *mangled_str; + int dmgl_opts = DMGL_NO_OPTS; + + if (verbosity >= 2) + { + dmgl_opts = DMGL_VERBOSE + | DMGL_ANSI + | DMGL_GNU_V3 + | DMGL_RET_POSTFIX; + if (TREE_CODE (decl) == FUNCTION_DECL) + dmgl_opts |= DMGL_PARAMS; + } + + mangled_str = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)); + str = cplus_demangle_v3 (mangled_str, dmgl_opts); + return (str) ? str : mangled_str; + } + + return IDENTIFIER_POINTER (DECL_NAME (decl)); +} + + +/* Create a new VAR_DECL and copy information from VAR to it. */ + +tree +copy_var_decl (tree var, tree name, tree type) +{ + tree copy = build_decl (DECL_SOURCE_LOCATION (var), VAR_DECL, name, type); + + TREE_ADDRESSABLE (copy) = TREE_ADDRESSABLE (var); + TREE_THIS_VOLATILE (copy) = TREE_THIS_VOLATILE (var); + DECL_GIMPLE_REG_P (copy) = DECL_GIMPLE_REG_P (var); + DECL_ARTIFICIAL (copy) = DECL_ARTIFICIAL (var); + DECL_IGNORED_P (copy) = DECL_IGNORED_P (var); + DECL_CONTEXT (copy) = DECL_CONTEXT (var); + TREE_NO_WARNING (copy) = TREE_NO_WARNING (var); + TREE_USED (copy) = 1; + DECL_SEEN_IN_BIND_EXPR_P (copy) = 1; + DECL_ATTRIBUTES (copy) = DECL_ATTRIBUTES (var); + + return copy; +} + +/* Given SSA_NAMEs NAME1 and NAME2, return true if they are candidates for + coalescing together, false otherwise. + + This must stay consistent with var_map_base_init in tree-ssa-live.c. */ + +bool +gimple_can_coalesce_p (tree name1, tree name2) +{ + /* First check the SSA_NAME's associated DECL. We only want to + coalesce if they have the same DECL or both have no associated DECL. */ + tree var1 = SSA_NAME_VAR (name1); + tree var2 = SSA_NAME_VAR (name2); + var1 = (var1 && (!VAR_P (var1) || !DECL_IGNORED_P (var1))) ? var1 : NULL_TREE; + var2 = (var2 && (!VAR_P (var2) || !DECL_IGNORED_P (var2))) ? var2 : NULL_TREE; + if (var1 != var2) + return false; + + /* Now check the types. If the types are the same, then we should + try to coalesce V1 and V2. */ + tree t1 = TREE_TYPE (name1); + tree t2 = TREE_TYPE (name2); + if (t1 == t2) + return true; + + /* If the types are not the same, check for a canonical type match. This + (for example) allows coalescing when the types are fundamentally the + same, but just have different names. + + Note pointer types with different address spaces may have the same + canonical type. Those are rejected for coalescing by the + types_compatible_p check. */ + if (TYPE_CANONICAL (t1) + && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2) + && types_compatible_p (t1, t2)) + return true; + + return false; +} + + +/* ----- Expression related ----- */ + +/* Extract the operands and code for expression EXPR into *SUBCODE_P, + *OP1_P, *OP2_P and *OP3_P respectively. */ + +void +extract_ops_from_tree_1 (tree expr, enum tree_code *subcode_p, tree *op1_p, + tree *op2_p, tree *op3_p) +{ + enum gimple_rhs_class grhs_class; + + *subcode_p = TREE_CODE (expr); + grhs_class = get_gimple_rhs_class (*subcode_p); + + if (grhs_class == GIMPLE_TERNARY_RHS) + { + *op1_p = TREE_OPERAND (expr, 0); + *op2_p = TREE_OPERAND (expr, 1); + *op3_p = TREE_OPERAND (expr, 2); + } + else if (grhs_class == GIMPLE_BINARY_RHS) + { + *op1_p = TREE_OPERAND (expr, 0); + *op2_p = TREE_OPERAND (expr, 1); + *op3_p = NULL_TREE; + } + else if (grhs_class == GIMPLE_UNARY_RHS) + { + *op1_p = TREE_OPERAND (expr, 0); + *op2_p = NULL_TREE; + *op3_p = NULL_TREE; + } + else if (grhs_class == GIMPLE_SINGLE_RHS) + { + *op1_p = expr; + *op2_p = NULL_TREE; + *op3_p = NULL_TREE; + } + else + gcc_unreachable (); +} + +/* Extract operands for a GIMPLE_COND statement out of COND_EXPR tree COND. */ + +void +gimple_cond_get_ops_from_tree (tree cond, enum tree_code *code_p, + tree *lhs_p, tree *rhs_p) +{ + gcc_assert (TREE_CODE_CLASS (TREE_CODE (cond)) == tcc_comparison + || TREE_CODE (cond) == TRUTH_NOT_EXPR + || is_gimple_min_invariant (cond) + || SSA_VAR_P (cond)); + + extract_ops_from_tree (cond, code_p, lhs_p, rhs_p); + + /* Canonicalize conditionals of the form 'if (!VAL)'. */ + if (*code_p == TRUTH_NOT_EXPR) + { + *code_p = EQ_EXPR; + gcc_assert (*lhs_p && *rhs_p == NULL_TREE); + *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p)); + } + /* Canonicalize conditionals of the form 'if (VAL)' */ + else if (TREE_CODE_CLASS (*code_p) != tcc_comparison) + { + *code_p = NE_EXPR; + gcc_assert (*lhs_p && *rhs_p == NULL_TREE); + *rhs_p = build_zero_cst (TREE_TYPE (*lhs_p)); + } +} + +/* Return true if T is a valid LHS for a GIMPLE assignment expression. */ + +bool +is_gimple_lvalue (tree t) +{ + return (is_gimple_addressable (t) + || TREE_CODE (t) == WITH_SIZE_EXPR + /* These are complex lvalues, but don't have addresses, so they + go here. */ + || TREE_CODE (t) == BIT_FIELD_REF); +} + +/* Return true if T is a GIMPLE condition. */ + +bool +is_gimple_condexpr (tree t) +{ + return (is_gimple_val (t) || (COMPARISON_CLASS_P (t) + && !tree_could_throw_p (t) + && is_gimple_val (TREE_OPERAND (t, 0)) + && is_gimple_val (TREE_OPERAND (t, 1)))); +} + +/* Return true if T is a gimple address. */ + +bool +is_gimple_address (const_tree t) +{ + tree op; + + if (TREE_CODE (t) != ADDR_EXPR) + return false; + + op = TREE_OPERAND (t, 0); + while (handled_component_p (op)) + { + if ((TREE_CODE (op) == ARRAY_REF + || TREE_CODE (op) == ARRAY_RANGE_REF) + && !is_gimple_val (TREE_OPERAND (op, 1))) + return false; + + op = TREE_OPERAND (op, 0); + } + + if (CONSTANT_CLASS_P (op) || TREE_CODE (op) == MEM_REF) + return true; + + switch (TREE_CODE (op)) + { + case PARM_DECL: + case RESULT_DECL: + case LABEL_DECL: + case FUNCTION_DECL: + case VAR_DECL: + case CONST_DECL: + return true; + + default: + return false; + } +} + +/* Return true if T is a gimple invariant address. */ + +bool +is_gimple_invariant_address (const_tree t) +{ + const_tree op; + + if (TREE_CODE (t) != ADDR_EXPR) + return false; + + op = strip_invariant_refs (TREE_OPERAND (t, 0)); + if (!op) + return false; + + if (TREE_CODE (op) == MEM_REF) + { + const_tree op0 = TREE_OPERAND (op, 0); + return (TREE_CODE (op0) == ADDR_EXPR + && (CONSTANT_CLASS_P (TREE_OPERAND (op0, 0)) + || decl_address_invariant_p (TREE_OPERAND (op0, 0)))); + } + + return CONSTANT_CLASS_P (op) || decl_address_invariant_p (op); +} + +/* Return true if T is a gimple invariant address at IPA level + (so addresses of variables on stack are not allowed). */ + +bool +is_gimple_ip_invariant_address (const_tree t) +{ + const_tree op; + + if (TREE_CODE (t) != ADDR_EXPR) + return false; + + op = strip_invariant_refs (TREE_OPERAND (t, 0)); + if (!op) + return false; + + if (TREE_CODE (op) == MEM_REF) + { + const_tree op0 = TREE_OPERAND (op, 0); + return (TREE_CODE (op0) == ADDR_EXPR + && (CONSTANT_CLASS_P (TREE_OPERAND (op0, 0)) + || decl_address_ip_invariant_p (TREE_OPERAND (op0, 0)))); + } + + return CONSTANT_CLASS_P (op) || decl_address_ip_invariant_p (op); +} + +/* Return true if T is a GIMPLE minimal invariant. It's a restricted + form of function invariant. */ + +bool +is_gimple_min_invariant (const_tree t) +{ + if (TREE_CODE (t) == ADDR_EXPR) + return is_gimple_invariant_address (t); + + return is_gimple_constant (t); +} + +/* Return true if T is a GIMPLE interprocedural invariant. It's a restricted + form of gimple minimal invariant. */ + +bool +is_gimple_ip_invariant (const_tree t) +{ + if (TREE_CODE (t) == ADDR_EXPR) + return is_gimple_ip_invariant_address (t); + + return is_gimple_constant (t); +} + +/* Return true if T is a non-aggregate register variable. */ + +bool +is_gimple_reg (tree t) +{ + if (virtual_operand_p (t)) + return false; + + if (TREE_CODE (t) == SSA_NAME) + return true; + + if (!is_gimple_variable (t)) + return false; + + if (!is_gimple_reg_type (TREE_TYPE (t))) + return false; + + /* A volatile decl is not acceptable because we can't reuse it as + needed. We need to copy it into a temp first. */ + if (TREE_THIS_VOLATILE (t)) + return false; + + /* We define "registers" as things that can be renamed as needed, + which with our infrastructure does not apply to memory. */ + if (needs_to_live_in_memory (t)) + return false; + + /* Hard register variables are an interesting case. For those that + are call-clobbered, we don't know where all the calls are, since + we don't (want to) take into account which operations will turn + into libcalls at the rtl level. For those that are call-saved, + we don't currently model the fact that calls may in fact change + global hard registers, nor do we examine ASM_CLOBBERS at the tree + level, and so miss variable changes that might imply. All around, + it seems safest to not do too much optimization with these at the + tree level at all. We'll have to rely on the rtl optimizers to + clean this up, as there we've got all the appropriate bits exposed. */ + if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t)) + return false; + + /* Complex and vector values must have been put into SSA-like form. + That is, no assignments to the individual components. */ + if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE + || TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE) + return DECL_GIMPLE_REG_P (t); + + return true; +} + + +/* Return true if T is a GIMPLE rvalue, i.e. an identifier or a constant. */ + +bool +is_gimple_val (tree t) +{ + /* Make loads from volatiles and memory vars explicit. */ + if (is_gimple_variable (t) + && is_gimple_reg_type (TREE_TYPE (t)) + && !is_gimple_reg (t)) + return false; + + return (is_gimple_variable (t) || is_gimple_min_invariant (t)); +} + +/* Similarly, but accept hard registers as inputs to asm statements. */ + +bool +is_gimple_asm_val (tree t) +{ + if (TREE_CODE (t) == VAR_DECL && DECL_HARD_REGISTER (t)) + return true; + + return is_gimple_val (t); +} + +/* Return true if T is a GIMPLE minimal lvalue. */ + +bool +is_gimple_min_lval (tree t) +{ + if (!(t = CONST_CAST_TREE (strip_invariant_refs (t)))) + return false; + return (is_gimple_id (t) || TREE_CODE (t) == MEM_REF); +} + +/* Return true if T is a valid function operand of a CALL_EXPR. */ + +bool +is_gimple_call_addr (tree t) +{ + return (TREE_CODE (t) == OBJ_TYPE_REF || is_gimple_val (t)); +} + +/* Return true if T is a valid address operand of a MEM_REF. */ + +bool +is_gimple_mem_ref_addr (tree t) +{ + return (is_gimple_reg (t) + || TREE_CODE (t) == INTEGER_CST + || (TREE_CODE (t) == ADDR_EXPR + && (CONSTANT_CLASS_P (TREE_OPERAND (t, 0)) + || decl_address_invariant_p (TREE_OPERAND (t, 0))))); +} |