diff options
Diffstat (limited to 'REORG.TODO/sysdeps/i386/i586/memcpy.S')
| -rw-r--r-- | REORG.TODO/sysdeps/i386/i586/memcpy.S | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/i386/i586/memcpy.S b/REORG.TODO/sysdeps/i386/i586/memcpy.S new file mode 100644 index 0000000000..6474a3f653 --- /dev/null +++ b/REORG.TODO/sysdeps/i386/i586/memcpy.S @@ -0,0 +1,124 @@ +/* Highly optimized version for i586. + Copyright (C) 1997-2017 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, see + <http://www.gnu.org/licenses/>. */ + +#include <sysdep.h> +#include "asm-syntax.h" + +#define PARMS 4+8 /* space for 2 saved regs */ +#define RTN PARMS +#define DEST RTN +#define SRC DEST+4 +#define LEN SRC+4 + + .text +#if defined PIC && IS_IN (libc) +ENTRY (__memcpy_chk) + movl 12(%esp), %eax + cmpl %eax, 16(%esp) + jb HIDDEN_JUMPTARGET (__chk_fail) +END (__memcpy_chk) +#endif +ENTRY (memcpy) + + 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 + 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 +#ifndef USE_AS_MEMPCPY + movl DEST(%esp), %eax +#endif + +L(1): rep; movsb + +#ifdef USE_AS_MEMPCPY + movl %edi, %eax +#endif + + popl %esi + cfi_adjust_cfa_offset (-4) + cfi_restore (esi) + popl %edi + cfi_adjust_cfa_offset (-4) + cfi_restore (edi) + + ret +END (memcpy) +#ifndef USE_AS_MEMPCPY +libc_hidden_builtin_def (memcpy) +#endif |