Also resolves: PR middle-end/92939 - missing -Wstringop-overflow on negative index from the end of array gcc/ChangeLog: PR middle-end/95353 PR middle-end/92939 * builtins.c (inform_access): New function. (check_access): Call it. Add argument. (addr_decl_size): Remove. (get_range): New function. (compute_objsize): New overload. Only use compute_builtin_object_size with raw memory function. (check_memop_access): Pass new argument to compute_objsize and check_access. (expand_builtin_memchr, expand_builtin_strcat): Same. (expand_builtin_strcpy, expand_builtin_stpcpy_1): Same. (expand_builtin_stpncpy, check_strncat_sizes): Same. (expand_builtin_strncat, expand_builtin_strncpy): Same. (expand_builtin_memcmp): Same. * builtins.h (check_nul_terminated_array): Declare extern. (check_access): Add argument. (struct access_ref, struct access_data): New structs. * gimple-ssa-warn-restrict.c (clamp_offset): New helper. (builtin_access::overlap): Call it. * tree-object-size.c (decl_init_size): Declare extern. (addr_object_size): Correct offset computation. * tree-object-size.h (decl_init_size): Declare. * tree-ssa-strlen.c (handle_integral_assign): Remove a call to maybe_warn_overflow when assigning to an SSA_NAME. gcc/testsuite/ChangeLog: PR middle-end/95353 PR middle-end/92939 * c-c++-common/Wstringop-truncation.c: Remove an xfail. * gcc.dg/Warray-bounds-46.c: Remove a bogus warning. * gcc.dg/Wrestrict-9.c: Disable -Wstringop-overflow. * gcc.dg/Wstringop-overflow-12.c: Remove xfails. * gcc.dg/Wstringop-overflow-28.c: Same. * gcc.dg/builtin-stringop-chk-4.c: Same. * gcc.dg/builtin-stringop-chk-5.c: Same. * gcc.dg/builtin-stringop-chk-8.c: Same. * gcc.dg/strlenopt-74.c: Avoid buffer overflow. * gcc.dg/Wstringop-overflow-34.c: New test. * gcc.dg/Wstringop-overflow-35.c: New test. * gcc.dg/Wstringop-overflow-36.c: New test. * gcc.dg/Wstringop-overflow-37.c: New test. * gcc.dg/Wstringop-overflow-38.c: New test.
191 lines
7.7 KiB
C++
191 lines
7.7 KiB
C++
/* Expand builtin functions.
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Copyright (C) 1988-2020 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 3, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING3. If not see
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<http://www.gnu.org/licenses/>. */
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#ifndef GCC_BUILTINS_H
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#define GCC_BUILTINS_H
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#include <mpc.h>
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/* Target-dependent globals. */
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struct target_builtins {
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/* For each register that may be used for calling a function, this
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gives a mode used to copy the register's value. VOIDmode indicates
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the register is not used for calling a function. If the machine
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has register windows, this gives only the outbound registers.
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INCOMING_REGNO gives the corresponding inbound register. */
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fixed_size_mode_pod x_apply_args_mode[FIRST_PSEUDO_REGISTER];
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/* For each register that may be used for returning values, this gives
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a mode used to copy the register's value. VOIDmode indicates the
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register is not used for returning values. If the machine has
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register windows, this gives only the outbound registers.
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INCOMING_REGNO gives the corresponding inbound register. */
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fixed_size_mode_pod x_apply_result_mode[FIRST_PSEUDO_REGISTER];
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};
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extern struct target_builtins default_target_builtins;
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#if SWITCHABLE_TARGET
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extern struct target_builtins *this_target_builtins;
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#else
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#define this_target_builtins (&default_target_builtins)
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#endif
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/* Non-zero if __builtin_constant_p should be folded right away. */
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extern bool force_folding_builtin_constant_p;
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extern bool called_as_built_in (tree);
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extern bool get_object_alignment_1 (tree, unsigned int *,
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unsigned HOST_WIDE_INT *);
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extern unsigned int get_object_alignment (tree);
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extern bool get_pointer_alignment_1 (tree, unsigned int *,
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unsigned HOST_WIDE_INT *);
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extern unsigned int get_pointer_alignment (tree);
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extern unsigned string_length (const void*, unsigned, unsigned);
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struct c_strlen_data
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{
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/* [MINLEN, MAXBOUND, MAXLEN] is a range describing the length of
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one or more strings of possibly unknown length. For a single
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string of known length the range is a constant where
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MINLEN == MAXBOUND == MAXLEN holds.
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For other strings, MINLEN is the length of the shortest known
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string. MAXBOUND is the length of a string that could be stored
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in the largest array referenced by the expression. MAXLEN is
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the length of the longest sequence of non-zero bytes
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in an object referenced by the expression. For such strings,
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MINLEN <= MAXBOUND <= MAXLEN holds. For example, given:
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struct A { char a[7], b[]; };
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extern struct A *p;
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n = strlen (p->a);
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the computed range will be [0, 6, ALL_ONES].
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However, for a conditional expression involving a string
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of known length and an array of unknown bound such as
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n = strlen (i ? p->b : "123");
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the range will be [3, 3, ALL_ONES].
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MINLEN != 0 && MAXLEN == ALL_ONES indicates that MINLEN is
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the length of the shortest known string and implies that
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the shortest possible string referenced by the expression may
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actually be the empty string. This distinction is useful for
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diagnostics. get_range_strlen() return value distinguishes
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between these two cases.
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As the tighter (and more optimistic) bound, MAXBOUND is suitable
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for diagnostics but not for optimization.
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As the more conservative bound, MAXLEN is intended to be used
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for optimization. */
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tree minlen;
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tree maxlen;
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tree maxbound;
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/* When non-null, DECL refers to the declaration known to store
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an unterminated constant character array, as in:
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const char s[] = { 'a', 'b', 'c' };
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It is used to diagnose uses of such arrays in functions such as
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strlen() that expect a nul-terminated string as an argument. */
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tree decl;
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/* Non-constant offset from the beginning of a string not accounted
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for in the length range. Used to improve diagnostics. */
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tree off;
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};
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extern tree c_strlen (tree, int, c_strlen_data * = NULL, unsigned = 1);
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extern rtx c_readstr (const char *, scalar_int_mode, bool = true);
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extern void expand_builtin_setjmp_setup (rtx, rtx);
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extern void expand_builtin_setjmp_receiver (rtx);
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extern void expand_builtin_update_setjmp_buf (rtx);
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extern tree mathfn_built_in (tree, enum built_in_function fn);
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extern tree mathfn_built_in (tree, combined_fn);
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extern rtx builtin_strncpy_read_str (void *, HOST_WIDE_INT, scalar_int_mode);
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extern rtx builtin_memset_read_str (void *, HOST_WIDE_INT, scalar_int_mode);
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extern rtx expand_builtin_saveregs (void);
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extern tree std_build_builtin_va_list (void);
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extern tree std_fn_abi_va_list (tree);
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extern tree std_canonical_va_list_type (tree);
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extern void std_expand_builtin_va_start (tree, rtx);
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extern void expand_builtin_trap (void);
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extern void expand_ifn_atomic_bit_test_and (gcall *);
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extern void expand_ifn_atomic_compare_exchange (gcall *);
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extern rtx expand_builtin (tree, rtx, rtx, machine_mode, int);
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extern enum built_in_function builtin_mathfn_code (const_tree);
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extern tree fold_builtin_expect (location_t, tree, tree, tree, tree);
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extern bool avoid_folding_inline_builtin (tree);
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extern tree fold_call_expr (location_t, tree, bool);
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extern tree fold_builtin_call_array (location_t, tree, tree, int, tree *);
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extern bool validate_gimple_arglist (const gcall *, ...);
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extern rtx default_expand_builtin (tree, rtx, rtx, machine_mode, int);
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extern bool fold_builtin_next_arg (tree, bool);
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extern tree do_mpc_arg2 (tree, tree, tree, int, int (*)(mpc_ptr, mpc_srcptr, mpc_srcptr, mpc_rnd_t));
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extern tree fold_call_stmt (gcall *, bool);
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extern void set_builtin_user_assembler_name (tree decl, const char *asmspec);
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extern bool is_simple_builtin (tree);
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extern bool is_inexpensive_builtin (tree);
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class vr_values;
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tree gimple_call_alloc_size (gimple *, wide_int[2] = NULL,
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const vr_values * = NULL);
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extern tree compute_objsize (tree, int, tree * = NULL, tree * = NULL,
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const vr_values * = NULL);
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extern bool readonly_data_expr (tree exp);
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extern bool init_target_chars (void);
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extern unsigned HOST_WIDE_INT target_newline;
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extern unsigned HOST_WIDE_INT target_percent;
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extern char target_percent_s[3];
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extern char target_percent_c[3];
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extern char target_percent_s_newline[4];
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extern bool target_char_cst_p (tree t, char *p);
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extern internal_fn associated_internal_fn (tree);
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extern internal_fn replacement_internal_fn (gcall *);
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extern bool check_nul_terminated_array (tree, tree, tree = NULL_TREE);
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extern void warn_string_no_nul (location_t, const char *, tree, tree);
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extern tree unterminated_array (tree, tree * = NULL, bool * = NULL);
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extern bool builtin_with_linkage_p (tree);
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/* Describes a reference to an object used in an access. */
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struct access_ref
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{
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access_ref (): ref ()
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{
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/* Set to valid. */
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offrng[0] = offrng[1] = 0;
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/* Invalidate. */
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sizrng[0] = sizrng[1] = -1;
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}
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/* Reference to the object. */
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tree ref;
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/* Range of offsets into and sizes of the object(s). */
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offset_int offrng[2];
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offset_int sizrng[2];
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};
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/* Describes a pair of references used in an access by built-in
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functions like memcpy. */
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struct access_data
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{
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/* Destination and source of the access. */
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access_ref dst, src;
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};
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extern bool check_access (tree, tree, tree, tree, tree, tree, tree,
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bool = true, const access_data * = NULL);
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#endif /* GCC_BUILTINS_H */
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