1/* memset with REP MOVSB/STOSB
2   Copyright (C) 2015-2022 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, see
17   <https://www.gnu.org/licenses/>.  */
18
19#include <sysdep.h>
20
21#define CFI_PUSH(REG)						\
22  cfi_adjust_cfa_offset (4);					\
23  cfi_rel_offset (REG, 0)
24
25#define CFI_POP(REG)						\
26  cfi_adjust_cfa_offset (-4);					\
27  cfi_restore (REG)
28
29#define PUSH(REG)	pushl REG; CFI_PUSH (REG)
30#define POP(REG)	popl REG; CFI_POP (REG)
31
32#define STR1  8
33#define STR2  STR1+4
34#define N     STR2+4
35
36	.text
37#if defined SHARED && IS_IN (libc)
38ENTRY (__memset_chk)
39	movl	12(%esp), %eax
40	cmpl	%eax, 16(%esp)
41	jb	HIDDEN_JUMPTARGET (__chk_fail)
42END (__memset_chk)
43#endif
44ENTRY (memset)
45	PUSH    (%edi)
46	movl	N(%esp), %ecx
47	movl	STR1(%esp), %edi
48	movzbl	STR2(%esp), %eax
49	mov	%edi, %edx
50	rep	stosb
51	mov	%edx, %eax
52	POP     (%edi)
53	ret
54END (memset)
55
56libc_hidden_builtin_def (memset)
57