| /* Highly optimized version for i586. |
| Copyright (C) 1997, 2000, 2003, 2005 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| 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, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <sysdep.h> |
| #include "asm-syntax.h" |
| #include "bp-sym.h" |
| #include "bp-asm.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) |
| |
| #define PARMS LINKAGE+8 /* space for 2 saved regs */ |
| #define RTN PARMS |
| #define DEST RTN+RTN_SIZE |
| #define SRC DEST+PTR_SIZE |
| #define LEN SRC+PTR_SIZE |
| |
| .text |
| #if defined PIC && !defined NOT_IN_libc |
| ENTRY (__memcpy_chk) |
| movl 12(%esp), %eax |
| cmpl %eax, 16(%esp) |
| jb HIDDEN_JUMPTARGET (__chk_fail) |
| END (__memcpy_chk) |
| #endif |
| ENTRY (BP_SYM (memcpy)) |
| ENTER |
| |
| pushl %edi |
| cfi_adjust_cfa_offset (4) |
| pushl %esi |
| cfi_adjust_cfa_offset (4) |
| |
| movl DEST(%esp), %edi |
| cfi_rel_offset (edi, 4) |
| movl SRC(%esp), %esi |
| cfi_rel_offset (esi, 0) |
| movl LEN(%esp), %ecx |
| CHECK_BOUNDS_BOTH_WIDE (%edi, DEST(%esp), %ecx) |
| CHECK_BOUNDS_BOTH_WIDE (%esi, SRC(%esp), %ecx) |
| movl %edi, %eax |
| |
| /* We need this in any case. */ |
| cld |
| |
| /* Cutoff for the big loop is a size of 32 bytes since otherwise |
| the loop will never be entered. */ |
| cmpl $32, %ecx |
| jbe L(1) |
| |
| negl %eax |
| andl $3, %eax |
| subl %eax, %ecx |
| xchgl %eax, %ecx |
| |
| rep; movsb |
| |
| movl %eax, %ecx |
| subl $32, %ecx |
| js L(2) |
| |
| /* Read ahead to make sure we write in the cache since the stupid |
| i586 designers haven't implemented read-on-write-miss. */ |
| movl (%edi), %eax |
| L(3): movl 28(%edi), %edx |
| |
| /* Now correct the loop counter. Please note that in the following |
| code the flags are not changed anymore. */ |
| subl $32, %ecx |
| |
| movl (%esi), %eax |
| movl 4(%esi), %edx |
| movl %eax, (%edi) |
| movl %edx, 4(%edi) |
| movl 8(%esi), %eax |
| movl 12(%esi), %edx |
| movl %eax, 8(%edi) |
| movl %edx, 12(%edi) |
| movl 16(%esi), %eax |
| movl 20(%esi), %edx |
| movl %eax, 16(%edi) |
| movl %edx, 20(%edi) |
| movl 24(%esi), %eax |
| movl 28(%esi), %edx |
| movl %eax, 24(%edi) |
| movl %edx, 28(%edi) |
| |
| leal 32(%esi), %esi |
| leal 32(%edi), %edi |
| |
| jns L(3) |
| |
| /* Correct extra loop counter modification. */ |
| L(2): addl $32, %ecx |
| #if !MEMPCPY_P |
| movl DEST(%esp), %eax |
| #endif |
| |
| L(1): rep; movsb |
| |
| #if MEMPCPY_P |
| movl %edi, %eax |
| #endif |
| |
| popl %esi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (esi) |
| popl %edi |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (edi) |
| |
| LEAVE |
| RET_PTR |
| END (BP_SYM (memcpy)) |
| #if !MEMPCPY_P |
| libc_hidden_builtin_def (memcpy) |
| #endif |
