1/* Copy memory block and return pointer to following byte.
2 For Intel 80x86, x>=6.
3 This file is part of the GNU C Library.
4 Copyright (C) 1998-2024 Free Software Foundation, Inc.
5
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.
10
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.
15
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/>. */
19
20#include <sysdep.h>
21#include "asm-syntax.h"
22
23#define PARMS 4 /* no space for saved regs */
24#define RTN PARMS
25#define DEST RTN
26#define SRC DEST+4
27#define LEN SRC+4
28
29 .text
30#if defined SHARED && IS_IN (libc)
31ENTRY_CHK (__mempcpy_chk)
32 movl 12(%esp), %eax
33 cmpl %eax, 16(%esp)
34 jb HIDDEN_JUMPTARGET (__chk_fail)
35END_CHK (__mempcpy_chk)
36libc_hidden_builtin_def (__mempcpy_chk)
37#endif
38ENTRY (__mempcpy)
39
40 movl LEN(%esp), %ecx
41 movl %edi, %eax
42 cfi_register (edi, eax)
43 movl DEST(%esp), %edi
44 movl %esi, %edx
45 cfi_register (esi, edx)
46 movl SRC(%esp), %esi
47 cld
48 shrl $1, %ecx
49 jnc 1f
50 movsb
511: shrl $1, %ecx
52 jnc 2f
53 movsw
542: rep
55 movsl
56 xchgl %edi, %eax
57 cfi_restore (edi)
58 movl %edx, %esi
59 cfi_restore (esi)
60
61 ret
62END (__mempcpy)
63libc_hidden_def (__mempcpy)
64weak_alias (__mempcpy, mempcpy)
65libc_hidden_builtin_def (mempcpy)
66

source code of glibc/sysdeps/i386/i686/mempcpy.S