1 /* Highly optimized version for x86-64.
2 Copyright (C) 1997, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Based on i586 version contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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 <http://www.gnu.org/licenses/>. */
20 #include "_glibc_inc.h"
22 /* BEWARE: `#ifdef memcpy' means that memcpy is redefined as `mempcpy',
23 and the return value is the byte after the last one copied in
25 #define MEMPCPY_P (defined memcpy)
28 #if defined __PIC__ && !defined NOT_IN_libc && defined __UCLIBC_HAS_FORTIFY__
31 jb HIDDEN_JUMPTARGET (__chk_fail)
34 ENTRY (BP_SYM (memcpy))
35 /* Cutoff for the big loop is a size of 32 bytes since otherwise
36 the loop will never be entered. */
40 movq %rdi, %r10 /* Save value. */
43 /* We need this in any case. */
48 /* Align destination. */
61 /* Next 3 insns are 11 bytes total, make sure we decode them in one go */
64 /* Now correct the loop counter. Please note that in the following
65 code the flags are not changed anymore. */
82 /* Correct extra loop counter modification. */
87 movq %rdi, %rax /* Set return value. */
89 movq %r10, %rax /* Set return value. */
96 libc_hidden_def(memcpy)