/* go-lang.c -- Go frontend gcc interface.
Copyright (C) 2009-2020 Free Software Foundation, Inc.
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
. */
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "target.h"
#include "tree.h"
#include "gimple-expr.h"
#include "diagnostic.h"
#include "opts.h"
#include "fold-const.h"
#include "gimplify.h"
#include "stor-layout.h"
#include "debug.h"
#include "convert.h"
#include "langhooks.h"
#include "langhooks-def.h"
#include "common/common-target.h"
#include
#include "go-c.h"
#include "go-gcc.h"
#ifndef TARGET_AIX
#define TARGET_AIX 0
#endif
/* Language-dependent contents of a type. */
struct GTY(()) lang_type
{
char dummy;
};
/* Language-dependent contents of a decl. */
struct GTY(()) lang_decl
{
char dummy;
};
/* Language-dependent contents of an identifier. This must include a
tree_identifier. */
struct GTY(()) lang_identifier
{
struct tree_identifier common;
};
/* The resulting tree type. */
union GTY((desc ("TREE_CODE (&%h.generic) == IDENTIFIER_NODE"),
chain_next ("CODE_CONTAINS_STRUCT (TREE_CODE (&%h.generic), TS_COMMON) ? ((union lang_tree_node *) TREE_CHAIN (&%h.generic)) : NULL")))
lang_tree_node
{
union tree_node GTY((tag ("0"),
desc ("tree_node_structure (&%h)"))) generic;
struct lang_identifier GTY((tag ("1"))) identifier;
};
/* We don't use language_function. */
struct GTY(()) language_function
{
int dummy;
};
/* Option information we need to pass to go_create_gogo. */
static const char *go_pkgpath = NULL;
static const char *go_prefix = NULL;
static const char *go_relative_import_path = NULL;
static const char *go_c_header = NULL;
/* Language hooks. */
static bool
go_langhook_init (void)
{
build_common_tree_nodes (false);
/* I don't know why this has to be done explicitly. */
void_list_node = build_tree_list (NULL_TREE, void_type_node);
/* We must create the gogo IR after calling build_common_tree_nodes
(because Gogo::define_builtin_function_trees refers indirectly
to, e.g., unsigned_char_type_node) but before calling
build_common_builtin_nodes (because it calls, indirectly,
go_type_for_size). */
struct go_create_gogo_args args;
args.int_type_size = INT_TYPE_SIZE;
args.pointer_size = POINTER_SIZE;
args.pkgpath = go_pkgpath;
args.prefix = go_prefix;
args.relative_import_path = go_relative_import_path;
args.c_header = go_c_header;
args.check_divide_by_zero = go_check_divide_zero;
args.check_divide_overflow = go_check_divide_overflow;
args.compiling_runtime = go_compiling_runtime;
args.debug_escape_level = go_debug_escape_level;
args.debug_escape_hash = go_debug_escape_hash;
args.nil_check_size_threshold = TARGET_AIX ? -1 : 4096;
args.debug_optimization = go_debug_optimization;
args.need_eqtype = TARGET_AIX ? true : false;
args.linemap = go_get_linemap();
args.backend = go_get_backend();
go_create_gogo (&args);
build_common_builtin_nodes ();
/* The default precision for floating point numbers. This is used
for floating point constants with abstract type. This may
eventually be controllable by a command line option. */
mpfr_set_default_prec (256);
/* If necessary, override GCC's choice of minimum and maximum
exponents. This should only affect GCC middle-end
compilation-time, not correctness. */
mpfr_exp_t exp = mpfr_get_emax ();
if (exp < (1 << 16) - 1)
mpfr_set_emax ((1 << 16) - 1);
exp = mpfr_get_emin ();
if (exp > - ((1 << 16) - 1))
mpfr_set_emin (- ((1 << 16) - 1));
/* Go uses exceptions. */
using_eh_for_cleanups ();
return true;
}
/* The option mask. */
static unsigned int
go_langhook_option_lang_mask (void)
{
return CL_Go;
}
/* Initialize the options structure. */
static void
go_langhook_init_options_struct (struct gcc_options *opts)
{
/* Go says that signed overflow is precisely defined. */
opts->x_flag_wrapv = 1;
/* We default to using strict aliasing, since Go pointers are safe.
This is turned off for code that imports the "unsafe" package,
because using unsafe.pointer violates C style aliasing
requirements. */
opts->x_flag_strict_aliasing = 1;
/* Default to avoiding range issues for complex multiply and
divide. */
opts->x_flag_complex_method = 2;
/* The builtin math functions should not set errno. */
opts->x_flag_errno_math = 0;
opts->frontend_set_flag_errno_math = true;
/* Exceptions are used to handle recovering from panics. */
opts->x_flag_exceptions = 1;
opts->x_flag_non_call_exceptions = 1;
/* We need to keep pointers live for the garbage collector. */
opts->x_flag_keep_gc_roots_live = 1;
/* Go programs expect runtime.Callers to work, and that uses
libbacktrace that uses debug info. Set the debug info level to 1
by default. In post_options we will set the debug type if the
debug info level was not set back to 0 on the command line. */
opts->x_debug_info_level = DINFO_LEVEL_TERSE;
}
/* Infrastructure for a vector of char * pointers. */
typedef const char *go_char_p;
/* The list of directories to search after all the Go specific
directories have been searched. */
static vec go_search_dirs;
/* Handle Go specific options. Return 0 if we didn't do anything. */
static bool
go_langhook_handle_option (
size_t scode,
const char *arg,
HOST_WIDE_INT value,
int kind ATTRIBUTE_UNUSED,
location_t loc ATTRIBUTE_UNUSED,
const struct cl_option_handlers *handlers ATTRIBUTE_UNUSED)
{
enum opt_code code = (enum opt_code) scode;
bool ret = true;
switch (code)
{
case OPT_I:
go_add_search_path (arg);
break;
case OPT_L:
/* A -L option is assumed to come from the compiler driver.
This is a system directory. We search the following
directories, if they exist, before this one:
dir/go/VERSION
dir/go/VERSION/MACHINE
This is like include/c++. */
{
static const char dir_separator_str[] = { DIR_SEPARATOR, 0 };
size_t len;
char *p;
struct stat st;
len = strlen (arg);
p = XALLOCAVEC (char,
(len + sizeof "go" + sizeof DEFAULT_TARGET_VERSION
+ sizeof DEFAULT_TARGET_MACHINE + 3));
strcpy (p, arg);
if (len > 0 && !IS_DIR_SEPARATOR (p[len - 1]))
strcat (p, dir_separator_str);
strcat (p, "go");
strcat (p, dir_separator_str);
strcat (p, DEFAULT_TARGET_VERSION);
if (stat (p, &st) == 0 && S_ISDIR (st.st_mode))
{
go_add_search_path (p);
strcat (p, dir_separator_str);
strcat (p, DEFAULT_TARGET_MACHINE);
if (stat (p, &st) == 0 && S_ISDIR (st.st_mode))
go_add_search_path (p);
}
/* Search ARG too, but only after we've searched to Go
specific directories for all -L arguments. */
go_search_dirs.safe_push (arg);
}
break;
case OPT_fgo_dump_:
ret = go_enable_dump (arg) ? true : false;
break;
case OPT_fgo_optimize_:
ret = go_enable_optimize (arg, value) ? true : false;
break;
case OPT_fgo_pkgpath_:
go_pkgpath = arg;
break;
case OPT_fgo_prefix_:
go_prefix = arg;
break;
case OPT_fgo_relative_import_path_:
go_relative_import_path = arg;
break;
case OPT_fgo_c_header_:
go_c_header = arg;
break;
default:
/* Just return 1 to indicate that the option is valid. */
break;
}
return ret;
}
/* Run after parsing options. */
static bool
go_langhook_post_options (const char **pfilename ATTRIBUTE_UNUSED)
{
unsigned int ix;
const char *dir;
gcc_assert (num_in_fnames > 0);
FOR_EACH_VEC_ELT (go_search_dirs, ix, dir)
go_add_search_path (dir);
go_search_dirs.release ();
if (flag_excess_precision == EXCESS_PRECISION_DEFAULT)
flag_excess_precision = EXCESS_PRECISION_STANDARD;
/* Tail call optimizations can confuse uses of runtime.Callers. */
SET_OPTION_IF_UNSET (&global_options, &global_options_set,
flag_optimize_sibling_calls, 0);
/* Partial inlining can confuses uses of runtime.Callers.
See https://gcc.gnu.org/PR91663. */
SET_OPTION_IF_UNSET (&global_options, &global_options_set,
flag_partial_inlining, 0);
/* Go programs expect runtime.Callers to give the right answers,
which means that we can't combine functions even if they look the
same. */
SET_OPTION_IF_UNSET (&global_options, &global_options_set,
flag_ipa_icf_functions, 0);
/* If the debug info level is still 1, as set in init_options, make
sure that some debugging type is selected. */
if (global_options.x_debug_info_level == DINFO_LEVEL_TERSE
&& global_options.x_write_symbols == NO_DEBUG)
global_options.x_write_symbols = PREFERRED_DEBUGGING_TYPE;
/* We turn on stack splitting if we can. */
if (targetm_common.supports_split_stack (false, &global_options))
SET_OPTION_IF_UNSET (&global_options, &global_options_set,
flag_split_stack, 1);
/* If stack splitting is turned on, and the user did not explicitly
request function partitioning, turn off partitioning, as it
confuses the linker when trying to handle partitioned split-stack
code that calls a non-split-stack function. */
if (global_options.x_flag_split_stack
&& global_options.x_flag_reorder_blocks_and_partition)
SET_OPTION_IF_UNSET (&global_options, &global_options_set,
flag_reorder_blocks_and_partition, 0);
/* Returning false means that the backend should be used. */
return false;
}
static void
go_langhook_parse_file (void)
{
go_parse_input_files (in_fnames, num_in_fnames, flag_syntax_only,
go_require_return_statement);
/* Final processing of globals and early debug info generation. */
go_write_globals ();
}
static tree
go_langhook_type_for_size (unsigned int bits, int unsignedp)
{
tree type;
if (unsignedp)
{
if (bits == INT_TYPE_SIZE)
type = unsigned_type_node;
else if (bits == CHAR_TYPE_SIZE)
type = unsigned_char_type_node;
else if (bits == SHORT_TYPE_SIZE)
type = short_unsigned_type_node;
else if (bits == LONG_TYPE_SIZE)
type = long_unsigned_type_node;
else if (bits == LONG_LONG_TYPE_SIZE)
type = long_long_unsigned_type_node;
else
type = make_unsigned_type(bits);
}
else
{
if (bits == INT_TYPE_SIZE)
type = integer_type_node;
else if (bits == CHAR_TYPE_SIZE)
type = signed_char_type_node;
else if (bits == SHORT_TYPE_SIZE)
type = short_integer_type_node;
else if (bits == LONG_TYPE_SIZE)
type = long_integer_type_node;
else if (bits == LONG_LONG_TYPE_SIZE)
type = long_long_integer_type_node;
else
type = make_signed_type(bits);
}
return type;
}
static tree
go_langhook_type_for_mode (machine_mode mode, int unsignedp)
{
tree type;
/* Go has no vector types. Build them here. FIXME: It does not
make sense for the middle-end to ask the frontend for a type
which the frontend does not support. However, at least for now
it is required. See PR 46805. */
if (GET_MODE_CLASS (mode) == MODE_VECTOR_BOOL
&& valid_vector_subparts_p (GET_MODE_NUNITS (mode)))
{
unsigned int elem_bits = vector_element_size (GET_MODE_BITSIZE (mode),
GET_MODE_NUNITS (mode));
tree bool_type = build_nonstandard_boolean_type (elem_bits);
return build_vector_type_for_mode (bool_type, mode);
}
else if (VECTOR_MODE_P (mode)
&& valid_vector_subparts_p (GET_MODE_NUNITS (mode)))
{
tree inner;
inner = go_langhook_type_for_mode (GET_MODE_INNER (mode), unsignedp);
if (inner != NULL_TREE)
return build_vector_type_for_mode (inner, mode);
return NULL_TREE;
}
scalar_int_mode imode;
scalar_float_mode fmode;
complex_mode cmode;
if (is_int_mode (mode, &imode))
return go_langhook_type_for_size (GET_MODE_BITSIZE (imode), unsignedp);
else if (is_float_mode (mode, &fmode))
{
switch (GET_MODE_BITSIZE (fmode))
{
case 32:
return float_type_node;
case 64:
return double_type_node;
default:
// We have to check for long double in order to support
// i386 excess precision.
if (fmode == TYPE_MODE(long_double_type_node))
return long_double_type_node;
}
}
else if (is_complex_float_mode (mode, &cmode))
{
switch (GET_MODE_BITSIZE (cmode))
{
case 64:
return complex_float_type_node;
case 128:
return complex_double_type_node;
default:
// We have to check for long double in order to support
// i386 excess precision.
if (cmode == TYPE_MODE(complex_long_double_type_node))
return complex_long_double_type_node;
}
}
#if HOST_BITS_PER_WIDE_INT >= 64
/* The middle-end and some backends rely on TImode being supported
for 64-bit HWI. */
if (mode == TImode)
{
type = build_nonstandard_integer_type (GET_MODE_BITSIZE (TImode),
unsignedp);
if (type && TYPE_MODE (type) == TImode)
return type;
}
#endif
return NULL_TREE;
}
/* Record a builtin function. We just ignore builtin functions. */
static tree
go_langhook_builtin_function (tree decl)
{
return decl;
}
/* Return true if we are in the global binding level. */
static bool
go_langhook_global_bindings_p (void)
{
return current_function_decl == NULL_TREE;
}
/* Push a declaration into the current binding level. We can't
usefully implement this since we don't want to convert from tree
back to one of our internal data structures. I think the only way
this is used is to record a decl which is to be returned by
getdecls, and we could implement it for that purpose if
necessary. */
static tree
go_langhook_pushdecl (tree decl ATTRIBUTE_UNUSED)
{
gcc_unreachable ();
}
/* This hook is used to get the current list of declarations as trees.
We don't support that; instead we use the write_globals hook. This
can't simply crash because it is called by -gstabs. */
static tree
go_langhook_getdecls (void)
{
return NULL;
}
/* Go specific gimplification. We need to gimplify
CALL_EXPR_STATIC_CHAIN, because the gimplifier doesn't handle
it. */
static int
go_langhook_gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p)
{
if (TREE_CODE (*expr_p) == CALL_EXPR
&& CALL_EXPR_STATIC_CHAIN (*expr_p) != NULL_TREE)
gimplify_expr (&CALL_EXPR_STATIC_CHAIN (*expr_p), pre_p, post_p,
is_gimple_val, fb_rvalue);
return GS_UNHANDLED;
}
/* Return a decl for the exception personality function. The function
itself is implemented in libgo/runtime/go-unwind.c. */
static tree
go_langhook_eh_personality (void)
{
static tree personality_decl;
if (personality_decl == NULL_TREE)
{
personality_decl = build_personality_function ("gccgo");
go_preserve_from_gc (personality_decl);
}
return personality_decl;
}
/* Functions called directly by the generic backend. */
tree
convert (tree type, tree expr)
{
if (type == error_mark_node
|| expr == error_mark_node
|| TREE_TYPE (expr) == error_mark_node)
return error_mark_node;
if (type == TREE_TYPE (expr))
return expr;
if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (TREE_TYPE (expr)))
return fold_convert (type, expr);
switch (TREE_CODE (type))
{
case VOID_TYPE:
case BOOLEAN_TYPE:
return fold_convert (type, expr);
case INTEGER_TYPE:
return fold (convert_to_integer (type, expr));
case POINTER_TYPE:
return fold (convert_to_pointer (type, expr));
case REAL_TYPE:
return fold (convert_to_real (type, expr));
case COMPLEX_TYPE:
return fold (convert_to_complex (type, expr));
default:
break;
}
gcc_unreachable ();
}
/* FIXME: This is a hack to preserve trees that we create from the
garbage collector. */
static GTY(()) tree go_gc_root;
void
go_preserve_from_gc (tree t)
{
go_gc_root = tree_cons (NULL_TREE, t, go_gc_root);
}
/* Convert an identifier for use in an error message. */
const char *
go_localize_identifier (const char *ident)
{
return identifier_to_locale (ident);
}
#undef LANG_HOOKS_NAME
#undef LANG_HOOKS_INIT
#undef LANG_HOOKS_OPTION_LANG_MASK
#undef LANG_HOOKS_INIT_OPTIONS_STRUCT
#undef LANG_HOOKS_HANDLE_OPTION
#undef LANG_HOOKS_POST_OPTIONS
#undef LANG_HOOKS_PARSE_FILE
#undef LANG_HOOKS_TYPE_FOR_MODE
#undef LANG_HOOKS_TYPE_FOR_SIZE
#undef LANG_HOOKS_BUILTIN_FUNCTION
#undef LANG_HOOKS_GLOBAL_BINDINGS_P
#undef LANG_HOOKS_PUSHDECL
#undef LANG_HOOKS_GETDECLS
#undef LANG_HOOKS_GIMPLIFY_EXPR
#undef LANG_HOOKS_EH_PERSONALITY
#define LANG_HOOKS_NAME "GNU Go"
#define LANG_HOOKS_INIT go_langhook_init
#define LANG_HOOKS_OPTION_LANG_MASK go_langhook_option_lang_mask
#define LANG_HOOKS_INIT_OPTIONS_STRUCT go_langhook_init_options_struct
#define LANG_HOOKS_HANDLE_OPTION go_langhook_handle_option
#define LANG_HOOKS_POST_OPTIONS go_langhook_post_options
#define LANG_HOOKS_PARSE_FILE go_langhook_parse_file
#define LANG_HOOKS_TYPE_FOR_MODE go_langhook_type_for_mode
#define LANG_HOOKS_TYPE_FOR_SIZE go_langhook_type_for_size
#define LANG_HOOKS_BUILTIN_FUNCTION go_langhook_builtin_function
#define LANG_HOOKS_GLOBAL_BINDINGS_P go_langhook_global_bindings_p
#define LANG_HOOKS_PUSHDECL go_langhook_pushdecl
#define LANG_HOOKS_GETDECLS go_langhook_getdecls
#define LANG_HOOKS_GIMPLIFY_EXPR go_langhook_gimplify_expr
#define LANG_HOOKS_EH_PERSONALITY go_langhook_eh_personality
struct lang_hooks lang_hooks = LANG_HOOKS_INITIALIZER;
#include "gt-go-go-lang.h"
#include "gtype-go.h"