1 /* memset/bzero -- set memory area to CH/0
2 Highly optimized version for ix86, x>=6.
3 Copyright (C) 1999-2022 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
21 #include "asm-syntax.h"
23 #define PARMS 4+4 /* space for 1 saved reg */
30 #if defined SHARED && IS_IN (libc)
31 ENTRY_CHK (__memset_chk)
34 jb HIDDEN_JUMPTARGET (__chk_fail)
35 END_CHK (__memset_chk)
41 cfi_adjust_cfa_offset (4)
44 movzbl CHR(%esp), %eax
47 cfi_rel_offset (edi, 0)
50 jp 3f /* misaligned at 3, store just one byte below */
51 stosb /* misaligned at 1 or 2, store two bytes */
58 jnz 2f /* was misaligned at 2 or 3, now aligned */
59 stosb /* was misaligned at 1, store third byte */
64 imul $0x01010101, %eax
72 movl DEST(%esp), %eax /* start address of destination is result */
74 cfi_adjust_cfa_offset (-4)
79 libc_hidden_builtin_def (memset)