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Correct handling of constant representations containing embedded nuls.
Resolves: PR middle-end/95189 - memcmp being wrongly stripped like strcm PR middle-end/95886 - suboptimal memcpy with embedded zero bytes gcc/ChangeLog: PR middle-end/95189 PR middle-end/95886 * builtins.c (inline_expand_builtin_string_cmp): Rename... (inline_expand_builtin_bytecmp): ...to this. (builtin_memcpy_read_str): Don't expect data to be nul-terminated. (expand_builtin_memory_copy_args): Handle object representations with embedded nul bytes. (expand_builtin_memcmp): Same. (expand_builtin_strcmp): Adjust call to naming change. (expand_builtin_strncmp): Same. * expr.c (string_constant): Create empty strings with nonzero size. * fold-const.c (c_getstr): Rename locals and update comments. * tree.c (build_string): Accept null pointer argument. (build_string_literal): Same. * tree.h (build_string): Provide a default. (build_string_literal): Same. gcc/testsuite/ChangeLog: PR middle-end/95189 PR middle-end/95886 * gcc.dg/memcmp-pr95189.c: New test. * gcc.dg/strncmp-3.c: New test. * gcc.target/i386/memcpy-pr95886.c: New test.
This commit is contained in:
Martin Sebor
parent
3e99ed65cb
commit
d5803b9876
151
gcc/builtins.c
151
gcc/builtins.c
@ -122,7 +122,7 @@ static rtx expand_builtin_next_arg (void);
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static rtx expand_builtin_va_start (tree);
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static rtx expand_builtin_va_end (tree);
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static rtx expand_builtin_va_copy (tree);
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static rtx inline_expand_builtin_string_cmp (tree, rtx);
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static rtx inline_expand_builtin_bytecmp (tree, rtx);
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static rtx expand_builtin_strcmp (tree, rtx);
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static rtx expand_builtin_strncmp (tree, rtx, machine_mode);
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static rtx builtin_memcpy_read_str (void *, HOST_WIDE_INT, scalar_int_mode);
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@ -3230,20 +3230,18 @@ expand_builtin_strnlen (tree exp, rtx target, machine_mode target_mode)
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}
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/* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
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bytes from constant string DATA + OFFSET and return it as target
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constant. */
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bytes from bytes at DATA + OFFSET and return it reinterpreted as
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a target constant. */
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static rtx
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builtin_memcpy_read_str (void *data, HOST_WIDE_INT offset,
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scalar_int_mode mode)
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{
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const char *str = (const char *) data;
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/* The REPresentation pointed to by DATA need not be a nul-terminated
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string but the caller guarantees it's large enough for MODE. */
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const char *rep = (const char *) data;
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gcc_assert (offset >= 0
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&& ((unsigned HOST_WIDE_INT) offset + GET_MODE_SIZE (mode)
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<= strlen (str) + 1));
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return c_readstr (str + offset, mode);
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return c_readstr (rep + offset, mode, /*nul_terminated=*/false);
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}
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/* LEN specify length of the block of memcpy/memset operation.
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@ -4414,7 +4412,6 @@ expand_builtin_memory_copy_args (tree dest, tree src, tree len,
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rtx target, tree exp, memop_ret retmode,
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bool might_overlap)
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{
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const char *src_str;
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unsigned int src_align = get_pointer_alignment (src);
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unsigned int dest_align = get_pointer_alignment (dest);
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rtx dest_mem, src_mem, dest_addr, len_rtx;
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@ -4446,24 +4443,29 @@ expand_builtin_memory_copy_args (tree dest, tree src, tree len,
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len_rtx = expand_normal (len);
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determine_block_size (len, len_rtx, &min_size, &max_size,
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&probable_max_size);
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src_str = c_getstr (src);
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/* If SRC is a string constant and block move would be done by
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pieces, we can avoid loading the string from memory and only
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stored the computed constants. This works in the overlap
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(memmove) case as well because store_by_pieces just generates a
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series of stores of constants from the string constant returned
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by c_getstr(). */
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if (src_str
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/* Try to get the byte representation of the constant SRC points to,
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with its byte size in NBYTES. */
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unsigned HOST_WIDE_INT nbytes;
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const char *rep = c_getstr (src, &nbytes);
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/* If the function's constant bound LEN_RTX is less than or equal
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to the byte size of the representation of the constant argument,
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and if block move would be done by pieces, we can avoid loading
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the bytes from memory and only store the computed constant.
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This works in the overlap (memmove) case as well because
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store_by_pieces just generates a series of stores of constants
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from the representation returned by c_getstr(). */
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if (rep
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&& CONST_INT_P (len_rtx)
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&& (unsigned HOST_WIDE_INT) INTVAL (len_rtx) <= strlen (src_str) + 1
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&& (unsigned HOST_WIDE_INT) INTVAL (len_rtx) <= nbytes
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&& can_store_by_pieces (INTVAL (len_rtx), builtin_memcpy_read_str,
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CONST_CAST (char *, src_str),
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CONST_CAST (char *, rep),
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dest_align, false))
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{
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dest_mem = store_by_pieces (dest_mem, INTVAL (len_rtx),
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builtin_memcpy_read_str,
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CONST_CAST (char *, src_str),
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CONST_CAST (char *, rep),
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dest_align, false, retmode);
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dest_mem = force_operand (XEXP (dest_mem, 0), target);
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dest_mem = convert_memory_address (ptr_mode, dest_mem);
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@ -4487,7 +4489,8 @@ expand_builtin_memory_copy_args (tree dest, tree src, tree len,
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dest_addr = emit_block_move_hints (dest_mem, src_mem, len_rtx, method,
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expected_align, expected_size,
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min_size, max_size, probable_max_size,
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use_mempcpy_call, &is_move_done, might_overlap);
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use_mempcpy_call, &is_move_done,
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might_overlap);
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/* Bail out when a mempcpy call would be expanded as libcall and when
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we have a target that provides a fast implementation
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@ -5322,7 +5325,7 @@ expand_builtin_memcmp (tree exp, rtx target, bool result_eq)
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if (!result_eq && fcode != BUILT_IN_BCMP)
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{
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result = inline_expand_builtin_string_cmp (exp, target);
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result = inline_expand_builtin_bytecmp (exp, target);
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if (result)
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return result;
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}
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@ -5350,26 +5353,32 @@ expand_builtin_memcmp (tree exp, rtx target, bool result_eq)
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by_pieces_constfn constfn = NULL;
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const char *src_str = c_getstr (arg2);
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if (result_eq && src_str == NULL)
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/* Try to get the byte representation of the constant ARG2 (or, only
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when the function's result is used for equality to zero, ARG1)
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points to, with its byte size in NBYTES. */
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unsigned HOST_WIDE_INT nbytes;
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const char *rep = c_getstr (arg2, &nbytes);
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if (result_eq && rep == NULL)
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{
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src_str = c_getstr (arg1);
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if (src_str != NULL)
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/* For equality to zero the arguments are interchangeable. */
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rep = c_getstr (arg1, &nbytes);
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if (rep != NULL)
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std::swap (arg1_rtx, arg2_rtx);
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}
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/* If SRC is a string constant and block move would be done
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by pieces, we can avoid loading the string from memory
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and only stored the computed constants. */
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if (src_str
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/* If the function's constant bound LEN_RTX is less than or equal
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to the byte size of the representation of the constant argument,
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and if block move would be done by pieces, we can avoid loading
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the bytes from memory and only store the computed constant result. */
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if (rep
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&& CONST_INT_P (len_rtx)
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&& (unsigned HOST_WIDE_INT) INTVAL (len_rtx) <= strlen (src_str) + 1)
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&& (unsigned HOST_WIDE_INT) INTVAL (len_rtx) <= nbytes)
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constfn = builtin_memcpy_read_str;
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result = emit_block_cmp_hints (arg1_rtx, arg2_rtx, len_rtx,
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TREE_TYPE (len), target,
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result_eq, constfn,
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CONST_CAST (char *, src_str));
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CONST_CAST (char *, rep));
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if (result)
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{
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@ -5408,7 +5417,7 @@ expand_builtin_strcmp (tree exp, ATTRIBUTE_UNUSED rtx target)
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/* Due to the performance benefit, always inline the calls first. */
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rtx result = NULL_RTX;
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result = inline_expand_builtin_string_cmp (exp, target);
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result = inline_expand_builtin_bytecmp (exp, target);
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if (result)
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return result;
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@ -5532,7 +5541,7 @@ expand_builtin_strncmp (tree exp, ATTRIBUTE_UNUSED rtx target,
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/* Due to the performance benefit, always inline the calls first. */
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rtx result = NULL_RTX;
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result = inline_expand_builtin_string_cmp (exp, target);
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result = inline_expand_builtin_bytecmp (exp, target);
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if (result)
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return result;
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@ -7765,18 +7774,18 @@ inline_string_cmp (rtx target, tree var_str, const char *const_str,
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return result;
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}
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/* Inline expansion a call to str(n)cmp, with result going to
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TARGET if that's convenient.
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/* Inline expansion of a call to str(n)cmp and memcmp, with result going
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to TARGET if that's convenient.
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If the call is not been inlined, return NULL_RTX. */
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static rtx
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inline_expand_builtin_string_cmp (tree exp, rtx target)
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inline_expand_builtin_bytecmp (tree exp, rtx target)
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{
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tree fndecl = get_callee_fndecl (exp);
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enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
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unsigned HOST_WIDE_INT length = 0;
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bool is_ncmp = (fcode == BUILT_IN_STRNCMP || fcode == BUILT_IN_MEMCMP);
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/* Do NOT apply this inlining expansion when optimizing for size or
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/* Do NOT apply this inlining expansion when optimizing for size or
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optimization level below 2. */
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if (optimize < 2 || optimize_insn_for_size_p ())
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return NULL_RTX;
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@ -7799,29 +7808,47 @@ inline_expand_builtin_string_cmp (tree exp, rtx target)
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unsigned HOST_WIDE_INT len2 = 0;
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unsigned HOST_WIDE_INT len3 = 0;
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const char *src_str1 = c_getstr (arg1, &len1);
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const char *src_str2 = c_getstr (arg2, &len2);
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/* Get the object representation of the initializers of ARG1 and ARG2
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as strings, provided they refer to constant objects, with their byte
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sizes in LEN1 and LEN2, respectively. */
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const char *bytes1 = c_getstr (arg1, &len1);
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const char *bytes2 = c_getstr (arg2, &len2);
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/* If neither strings is constant string, the call is not qualify. */
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if (!src_str1 && !src_str2)
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/* Fail if neither argument refers to an initialized constant. */
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if (!bytes1 && !bytes2)
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return NULL_RTX;
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/* For strncmp, if the length is not a const, not qualify. */
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if (is_ncmp)
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{
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/* Fail if the memcmp/strncmp bound is not a constant. */
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if (!tree_fits_uhwi_p (len3_tree))
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return NULL_RTX;
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else
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len3 = tree_to_uhwi (len3_tree);
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len3 = tree_to_uhwi (len3_tree);
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if (fcode == BUILT_IN_MEMCMP)
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{
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/* Fail if the memcmp bound is greater than the size of either
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of the two constant objects. */
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if ((bytes1 && len1 < len3)
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|| (bytes2 && len2 < len3))
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return NULL_RTX;
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}
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}
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if (src_str1 != NULL)
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len1 = strnlen (src_str1, len1) + 1;
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if (fcode != BUILT_IN_MEMCMP)
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{
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/* For string functions (i.e., strcmp and strncmp) reduce LEN1
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and LEN2 to the length of the nul-terminated string stored
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in each. */
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if (bytes1 != NULL)
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len1 = strnlen (bytes1, len1) + 1;
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if (bytes2 != NULL)
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len2 = strnlen (bytes2, len2) + 1;
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}
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if (src_str2 != NULL)
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len2 = strnlen (src_str2, len2) + 1;
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int const_str_n = 0;
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/* See inline_string_cmp. */
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int const_str_n;
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if (!len1)
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const_str_n = 2;
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else if (!len2)
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@ -7831,23 +7858,23 @@ inline_expand_builtin_string_cmp (tree exp, rtx target)
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else
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const_str_n = 2;
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gcc_checking_assert (const_str_n > 0);
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length = (const_str_n == 1) ? len1 : len2;
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/* For strncmp only, compute the new bound as the smallest of
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the lengths of the two strings (plus 1) and the bound provided
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to the function. */
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unsigned HOST_WIDE_INT bound = (const_str_n == 1) ? len1 : len2;
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if (is_ncmp && len3 < bound)
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bound = len3;
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if (is_ncmp && len3 < length)
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length = len3;
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/* If the length of the comparision is larger than the threshold,
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/* If the bound of the comparison is larger than the threshold,
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do nothing. */
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if (length > (unsigned HOST_WIDE_INT)
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param_builtin_string_cmp_inline_length)
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if (bound > (unsigned HOST_WIDE_INT) param_builtin_string_cmp_inline_length)
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return NULL_RTX;
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machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
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/* Now, start inline expansion the call. */
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return inline_string_cmp (target, (const_str_n == 1) ? arg2 : arg1,
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(const_str_n == 1) ? src_str1 : src_str2, length,
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(const_str_n == 1) ? bytes1 : bytes2, bound,
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const_str_n, mode);
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}
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@ -11829,12 +11829,12 @@ string_constant (tree arg, tree *ptr_offset, tree *mem_size, tree *decl)
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while (TREE_CODE (chartype) == ARRAY_TYPE)
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chartype = TREE_TYPE (chartype);
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/* Convert a char array to an empty STRING_CST having an array
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of the expected type. */
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of the expected type and size. */
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if (!initsize)
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initsize = integer_zero_node;
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unsigned HOST_WIDE_INT size = tree_to_uhwi (initsize);
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init = build_string_literal (size ? 1 : 0, "", chartype, size);
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init = build_string_literal (size, NULL, chartype, size);
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init = TREE_OPERAND (init, 0);
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init = TREE_OPERAND (init, 0);
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@ -15487,24 +15487,29 @@ fold_build_pointer_plus_hwi_loc (location_t loc, tree ptr, HOST_WIDE_INT off)
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ptr, size_int (off));
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}
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/* Return a pointer P to a NUL-terminated string representing the sequence
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of constant characters referred to by SRC (or a subsequence of such
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characters within it if SRC is a reference to a string plus some
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constant offset). If STRLEN is non-null, store the number of bytes
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in the string constant including the terminating NUL char. *STRLEN is
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typically strlen(P) + 1 in the absence of embedded NUL characters. */
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/* Return a pointer P to a NUL-terminated string containing the sequence
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of bytes corresponding to the representation of the object referred to
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by SRC (or a subsequence of such bytes within it if SRC is a reference
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to an initialized constant array plus some constant offset).
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If STRSIZE is non-null, store the number of bytes in the constant
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sequence including the terminating NUL byte. *STRSIZE is equal to
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sizeof(A) - OFFSET where A is the array that stores the constant
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sequence that SRC points to and OFFSET is the byte offset of SRC from
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the beginning of A. SRC need not point to a string or even an array
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of characters but may point to an object of any type. */
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const char *
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c_getstr (tree src, unsigned HOST_WIDE_INT *strlen /* = NULL */)
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c_getstr (tree src, unsigned HOST_WIDE_INT *strsize /* = NULL */)
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{
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/* The offset into the array A storing the string, and A's byte size. */
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tree offset_node;
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tree mem_size;
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if (strlen)
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*strlen = 0;
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if (strsize)
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*strsize = 0;
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src = string_constant (src, &offset_node, &mem_size, NULL);
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if (src == 0)
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if (!src)
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return NULL;
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unsigned HOST_WIDE_INT offset = 0;
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@ -15519,34 +15524,44 @@ c_getstr (tree src, unsigned HOST_WIDE_INT *strlen /* = NULL */)
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if (!tree_fits_uhwi_p (mem_size))
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return NULL;
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/* STRING_LENGTH is the size of the string literal, including any
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embedded NULs. STRING_SIZE is the size of the array the string
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literal is stored in. */
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unsigned HOST_WIDE_INT string_length = TREE_STRING_LENGTH (src);
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unsigned HOST_WIDE_INT string_size = tree_to_uhwi (mem_size);
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/* ARRAY_SIZE is the byte size of the array the constant sequence
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is stored in and equal to sizeof A. INIT_BYTES is the number
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of bytes in the constant sequence used to initialize the array,
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including any embedded NULs as well as the terminating NUL (for
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strings), but not including any trailing zeros/NULs past
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the terminating one appended implicitly to a string literal to
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zero out the remainder of the array it's stored in. For example,
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given:
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const char a[7] = "abc\0d";
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n = strlen (a + 1);
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ARRAY_SIZE is 7, INIT_BYTES is 6, and OFFSET is 1. For a valid
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(i.e., nul-terminated) string with no embedded nuls, INIT_BYTES
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is equal to strlen (A) + 1. */
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const unsigned HOST_WIDE_INT array_size = tree_to_uhwi (mem_size);
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unsigned HOST_WIDE_INT init_bytes = TREE_STRING_LENGTH (src);
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/* Ideally this would turn into a gcc_checking_assert over time. */
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if (string_length > string_size)
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string_length = string_size;
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if (init_bytes > array_size)
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init_bytes = array_size;
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const char *string = TREE_STRING_POINTER (src);
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/* Ideally this would turn into a gcc_checking_assert over time. */
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if (string_length > string_size)
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string_length = string_size;
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if (init_bytes > array_size)
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init_bytes = array_size;
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if (string_length == 0
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|| offset >= string_size)
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if (init_bytes == 0 || offset >= array_size)
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return NULL;
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if (strlen)
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if (strsize)
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{
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/* Compute and store the length of the substring at OFFSET.
|
||||
All offsets past the initial length refer to null strings. */
|
||||
if (offset < string_length)
|
||||
*strlen = string_length - offset;
|
||||
/* Compute and store the number of characters from the beginning
|
||||
of the substring at OFFSET to the end, including the terminating
|
||||
nul. Offsets past the initial length refer to null strings. */
|
||||
if (offset < init_bytes)
|
||||
*strsize = init_bytes - offset;
|
||||
else
|
||||
*strlen = 1;
|
||||
*strsize = 1;
|
||||
}
|
||||
else
|
||||
{
|
||||
@ -15554,11 +15569,11 @@ c_getstr (tree src, unsigned HOST_WIDE_INT *strlen /* = NULL */)
|
||||
/* Support only properly NUL-terminated single byte strings. */
|
||||
if (tree_to_uhwi (TYPE_SIZE_UNIT (eltype)) != 1)
|
||||
return NULL;
|
||||
if (string[string_length - 1] != '\0')
|
||||
if (string[init_bytes - 1] != '\0')
|
||||
return NULL;
|
||||
}
|
||||
|
||||
return offset < string_length ? string + offset : "";
|
||||
return offset < init_bytes ? string + offset : "";
|
||||
}
|
||||
|
||||
/* Given a tree T, compute which bits in T may be nonzero. */
|
||||
|
||||
28
gcc/testsuite/gcc.dg/memcmp-pr95189.c
Normal file
28
gcc/testsuite/gcc.dg/memcmp-pr95189.c
Normal file
@ -0,0 +1,28 @@
|
||||
/* PR middle-end/95189 - memcmp being wrongly stripped like strcmp
|
||||
{ dg-do run }
|
||||
{ dg-options "-O2 -Wall" } */
|
||||
|
||||
char a4[] = "\0abc";
|
||||
char a8[] = "\0abcdefg";
|
||||
char a16[] = "\0abcdefghijklmno";
|
||||
|
||||
int cmp4 (void)
|
||||
{
|
||||
return __builtin_memcmp (a4, "\0\0\0\0", 4);
|
||||
}
|
||||
|
||||
int cmp8 (void)
|
||||
{
|
||||
return __builtin_memcmp (a8, "\0\0\0\0\0\0\0\0", 8);
|
||||
}
|
||||
|
||||
int cmp16 (void)
|
||||
{
|
||||
return __builtin_memcmp (a16, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16);
|
||||
}
|
||||
|
||||
int main (void)
|
||||
{
|
||||
if (cmp4 () < 1 || cmp8 () < 1 || cmp16 () < 1)
|
||||
__builtin_abort ();
|
||||
}
|
||||
57
gcc/testsuite/gcc.dg/strncmp-3.c
Normal file
57
gcc/testsuite/gcc.dg/strncmp-3.c
Normal file
@ -0,0 +1,57 @@
|
||||
/* PR middle-end/95189 - memcmp being wrongly stripped like strcmp
|
||||
{ dg-do run }
|
||||
{ dg-options "-O2 -Wall" } */
|
||||
|
||||
#define AB_D "ab\0d"
|
||||
#define ABCDEF_H "abcdef\0h"
|
||||
#define ABCDEFGHIJKLMN_P "abcdefghijklmn\0p"
|
||||
|
||||
char ab_d[] = AB_D;
|
||||
char abcdef_h[] = ABCDEF_H;
|
||||
|
||||
extern int strncmp (const char*, const char*, __SIZE_TYPE__);
|
||||
|
||||
__attribute__((noipa)) void sink (const void *p, ...) { (void)&p; }
|
||||
|
||||
#define strncmp(a, b, n) (sink (a, b), strncmp (a, b, n))
|
||||
|
||||
int main (void)
|
||||
{
|
||||
int zero = 0;
|
||||
|
||||
zero += strncmp (ab_d, AB_D, 1);
|
||||
zero += strncmp (ab_d, AB_D, 2);
|
||||
zero += strncmp (ab_d, AB_D, 3);
|
||||
zero += strncmp (ab_d, AB_D, 4);
|
||||
zero += strncmp (ab_d, AB_D, 5);
|
||||
|
||||
zero += strncmp (ab_d, ABCDEF_H, 1);
|
||||
zero += strncmp (ab_d, ABCDEF_H, 2);
|
||||
|
||||
zero += strncmp (abcdef_h, AB_D, 2);
|
||||
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 2);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 3);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 4);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 5);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 6);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 7);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 8);
|
||||
zero += strncmp (abcdef_h, ABCDEF_H, 9);
|
||||
|
||||
if (zero != 0)
|
||||
__builtin_abort ();
|
||||
|
||||
int neg = 0;
|
||||
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 3) < 0;
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 4) < 0;
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 5) < 0;
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 6) < 0;
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 7) < 0;
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 8) < 0;
|
||||
neg -= strncmp (ab_d, ABCDEF_H, 9) < 0;
|
||||
|
||||
if (neg != -7)
|
||||
__builtin_abort ();
|
||||
}
|
||||
107
gcc/testsuite/gcc.target/i386/memcpy-pr95886.c
Normal file
107
gcc/testsuite/gcc.target/i386/memcpy-pr95886.c
Normal file
@ -0,0 +1,107 @@
|
||||
/* PR middle-end/95886 - suboptimal memcpy with embedded zero bytes
|
||||
{ dg-do compile }
|
||||
{ dg-options "-O2 -Wall -fdump-rtl-expand" } */
|
||||
|
||||
const char a1234567890[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
|
||||
|
||||
void cpy_123456789 (void *d)
|
||||
{
|
||||
/* Expands into:
|
||||
movabsq $578437695752307201, %rax
|
||||
movb $9, 8(%rdi)
|
||||
movq %rax, (%rdi) */
|
||||
__builtin_memcpy (d, a1234567890, 9);
|
||||
}
|
||||
|
||||
const char a1234567800[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 0 };
|
||||
|
||||
void cpy_1234567800 (void *d)
|
||||
{
|
||||
/* Expands into:
|
||||
movabsq $578437695752307201, %rax
|
||||
movb $0, 8(%rdi)
|
||||
movq %rax, (%rdi) */
|
||||
__builtin_memcpy (d, a1234567800, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578437695752307201" 2 "expand"} } */
|
||||
|
||||
|
||||
const char a0234567890[10] = { 0, 2, 3, 4, 5, 6, 7, 8, 9 };
|
||||
|
||||
void cpy_023456789 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a0234567890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578437695752307200" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1034567890[10] = { 1, 0, 3, 4, 5, 6, 7, 8, 9 };
|
||||
|
||||
void cpy_103456789 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1034567890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578437695752306689" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1204567890[10] = { 1, 2, 0, 4, 5, 6, 7, 8, 9 };
|
||||
|
||||
void cpy_120456789 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1204567890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578437695752110593" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1230567890[10] = { 1, 2, 3, 0, 5, 6, 7, 8, 9 };
|
||||
|
||||
void cpy_123056789 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1230567890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578437695685198337" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1234067890[10] = { 1, 2, 3, 4, 0, 6, 7, 8, 9 };
|
||||
|
||||
void cpy_123406789 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1234067890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578437695685198337" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1234507890[10] = { 1, 2, 3, 4, 5, 0, 7, 8, 9 };
|
||||
|
||||
void cpy_123450789 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1234507890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 578431098682540545" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1234560890[10] = { 1, 2, 3, 4, 5, 6, 0, 8, 9 };
|
||||
|
||||
void cpy_123456089 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1234560890, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 576467370915332609" 1 "expand"} } */
|
||||
|
||||
|
||||
const char a1234567090[10] = { 1, 2, 3, 4, 5, 6, 7, 0, 9 };
|
||||
|
||||
void cpy_123456709 (void *d)
|
||||
{
|
||||
__builtin_memcpy (d, a1234567090, 9);
|
||||
}
|
||||
|
||||
/* { dg-final { scan-rtl-dump-times "const_int 1976943448883713" 1 "expand"} } */
|
||||
28
gcc/tree.c
28
gcc/tree.c
@ -2206,29 +2206,29 @@ build_real_from_int_cst (tree type, const_tree i)
|
||||
return v;
|
||||
}
|
||||
|
||||
/* Return a newly constructed STRING_CST node whose value is
|
||||
the LEN characters at STR.
|
||||
/* Return a newly constructed STRING_CST node whose value is the LEN
|
||||
characters at STR when STR is nonnull, or all zeros otherwise.
|
||||
Note that for a C string literal, LEN should include the trailing NUL.
|
||||
The TREE_TYPE is not initialized. */
|
||||
|
||||
tree
|
||||
build_string (int len, const char *str)
|
||||
build_string (unsigned len, const char *str /*= NULL */)
|
||||
{
|
||||
tree s;
|
||||
size_t length;
|
||||
|
||||
/* Do not waste bytes provided by padding of struct tree_string. */
|
||||
length = len + offsetof (struct tree_string, str) + 1;
|
||||
unsigned size = len + offsetof (struct tree_string, str) + 1;
|
||||
|
||||
record_node_allocation_statistics (STRING_CST, length);
|
||||
record_node_allocation_statistics (STRING_CST, size);
|
||||
|
||||
s = (tree) ggc_internal_alloc (length);
|
||||
tree s = (tree) ggc_internal_alloc (size);
|
||||
|
||||
memset (s, 0, sizeof (struct tree_typed));
|
||||
TREE_SET_CODE (s, STRING_CST);
|
||||
TREE_CONSTANT (s) = 1;
|
||||
TREE_STRING_LENGTH (s) = len;
|
||||
memcpy (s->string.str, str, len);
|
||||
if (str)
|
||||
memcpy (s->string.str, str, len);
|
||||
else
|
||||
memset (s->string.str, 0, len);
|
||||
s->string.str[len] = '\0';
|
||||
|
||||
return s;
|
||||
@ -11572,12 +11572,12 @@ build_alloca_call_expr (tree size, unsigned int align, HOST_WIDE_INT max_size)
|
||||
|
||||
/* Create a new constant string literal of type ELTYPE[SIZE] (or LEN
|
||||
if SIZE == -1) and return a tree node representing char* pointer to
|
||||
it as an ADDR_EXPR (ARRAY_REF (ELTYPE, ...)). The STRING_CST value
|
||||
is the LEN bytes at STR (the representation of the string, which may
|
||||
be wide). */
|
||||
it as an ADDR_EXPR (ARRAY_REF (ELTYPE, ...)). When STR is nonnull
|
||||
the STRING_CST value is the LEN bytes at STR (the representation
|
||||
of the string, which may be wide). Otherwise it's all zeros. */
|
||||
|
||||
tree
|
||||
build_string_literal (int len, const char *str,
|
||||
build_string_literal (unsigned len, const char *str /* = NULL */,
|
||||
tree eltype /* = char_type_node */,
|
||||
unsigned HOST_WIDE_INT size /* = -1 */)
|
||||
{
|
||||
|
||||
@ -4425,7 +4425,7 @@ extern tree build_one_cst (tree);
|
||||
extern tree build_minus_one_cst (tree);
|
||||
extern tree build_all_ones_cst (tree);
|
||||
extern tree build_zero_cst (tree);
|
||||
extern tree build_string (int, const char *);
|
||||
extern tree build_string (unsigned, const char * = NULL);
|
||||
extern tree build_poly_int_cst (tree, const poly_wide_int_ref &);
|
||||
extern tree build_tree_list (tree, tree CXX_MEM_STAT_INFO);
|
||||
extern tree build_tree_list_vec (const vec<tree, va_gc> * CXX_MEM_STAT_INFO);
|
||||
@ -4456,7 +4456,8 @@ extern tree build_call_expr_internal_loc_array (location_t, enum internal_fn,
|
||||
extern tree maybe_build_call_expr_loc (location_t, combined_fn, tree,
|
||||
int, ...);
|
||||
extern tree build_alloca_call_expr (tree, unsigned int, HOST_WIDE_INT);
|
||||
extern tree build_string_literal (int, const char *, tree = char_type_node,
|
||||
extern tree build_string_literal (unsigned, const char * = NULL,
|
||||
tree = char_type_node,
|
||||
unsigned HOST_WIDE_INT = HOST_WIDE_INT_M1U);
|
||||
|
||||
/* Construct various nodes representing data types. */
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user