/* Copy memory block and return pointer to beginning of destination block For Intel 80x86, x>=6. This file is part of the GNU C Library. Copyright (C) 1999-2016 Free Software Foundation, Inc. Contributed by Ulrich Drepper , 1999. 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 . */ #include #include "asm-syntax.h" #define PARMS 4 /* no space for saved regs */ #define RTN PARMS #define DEST RTN #define SRC DEST+4 #define LEN SRC+4 .text #if defined PIC && IS_IN (libc) ENTRY_CHK (__memcpy_chk) movl 12(%esp), %eax cmpl %eax, 16(%esp) jb HIDDEN_JUMPTARGET (__chk_fail) END_CHK (__memcpy_chk) #endif ENTRY (memcpy) movl %edi, %eax movl DEST(%esp), %edi movl %esi, %edx movl SRC(%esp), %esi movl %edi, %ecx xorl %esi, %ecx andl $3, %ecx movl LEN(%esp), %ecx cld jne .Lunaligned cmpl $3, %ecx jbe .Lunaligned testl $3, %esi je 1f movsb decl %ecx testl $3, %esi je 1f movsb decl %ecx testl $3, %esi je 1f movsb decl %ecx 1: pushl %eax movl %ecx, %eax shrl $2, %ecx andl $3, %eax rep movsl movl %eax, %ecx rep movsb popl %eax .Lend: movl %eax, %edi movl %edx, %esi movl DEST(%esp), %eax ret /* When we come here the pointers do not have the same alignment or the length is too short. No need to optimize for aligned memory accesses. */ .Lunaligned: shrl $1, %ecx jnc 1f movsb 1: shrl $1, %ecx jnc 2f movsw 2: rep movsl jmp .Lend END (memcpy) libc_hidden_builtin_def (memcpy)