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, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21 #include "_glibc_inc.h"
23 /* BEWARE: `#ifdef memcpy' means that memcpy is redefined as `mempcpy',
24 and the return value is the byte after the last one copied in
26 #define MEMPCPY_P (defined memcpy)
29 #if defined __PIC__ && !defined NOT_IN_libc && defined __UCLIBC_HAS_FORTIFY__
32 jb HIDDEN_JUMPTARGET (__chk_fail)
35 ENTRY (BP_SYM (memcpy))
36 /* Cutoff for the big loop is a size of 32 bytes since otherwise
37 the loop will never be entered. */
41 movq %rdi, %r10 /* Save value. */
44 /* We need this in any case. */
49 /* Align destination. */
62 /* Next 3 insns are 11 bytes total, make sure we decode them in one go */
65 /* Now correct the loop counter. Please note that in the following
66 code the flags are not changed anymore. */
83 /* Correct extra loop counter modification. */
88 movq %rdi, %rax /* Set return value. */
90 movq %r10, %rax /* Set return value. */
97 libc_hidden_def(memcpy)