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- /* Highly optimized version for x86-64.
- Copyright (C) 1997, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Based on i586 version contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
- The GNU C Library is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, see
- <http://www.gnu.org/licenses/>. */
- #include "_glibc_inc.h"
- /* BEWARE: `#ifdef memcpy' means that memcpy is redefined as `mempcpy',
- and the return value is the byte after the last one copied in
- the destination. */
- #define MEMPCPY_P (defined memcpy)
- .text
- #if defined __PIC__ && !defined NOT_IN_libc && defined __UCLIBC_HAS_FORTIFY__
- ENTRY (__memcpy_chk)
- cmpq %rdx, %rcx
- jb HIDDEN_JUMPTARGET (__chk_fail)
- END (__memcpy_chk)
- #endif
- ENTRY (BP_SYM (memcpy))
- /* Cutoff for the big loop is a size of 32 bytes since otherwise
- the loop will never be entered. */
- cmpq $32, %rdx
- movq %rdx, %rcx
- #if !MEMPCPY_P
- movq %rdi, %r10 /* Save value. */
- #endif
- /* We need this in any case. */
- cld
- jbe 1f
- /* Align destination. */
- movq %rdi, %rax
- negq %rax
- andq $7, %rax
- subq %rax, %rcx
- xchgq %rax, %rcx
- rep; movsb
- movq %rax, %rcx
- subq $32, %rcx
- js 2f
- /* Next 3 insns are 11 bytes total, make sure we decode them in one go */
- .p2align 4,,11
- 3:
- /* Now correct the loop counter. Please note that in the following
- code the flags are not changed anymore. */
- subq $32, %rcx
- movq (%rsi), %rax
- movq 8(%rsi), %rdx
- movq 16(%rsi), %r8
- movq 24(%rsi), %r9
- movq %rax, (%rdi)
- movq %rdx, 8(%rdi)
- movq %r8, 16(%rdi)
- movq %r9, 24(%rdi)
- leaq 32(%rsi), %rsi
- leaq 32(%rdi), %rdi
- jns 3b
- /* Correct extra loop counter modification. */
- 2: addq $32, %rcx
- 1: rep; movsb
- #if MEMPCPY_P
- movq %rdi, %rax /* Set return value. */
- #else
- movq %r10, %rax /* Set return value. */
-
- #endif
- ret
- END (BP_SYM (memcpy))
- #if !MEMPCPY_P
- libc_hidden_def(memcpy)
- #endif
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