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Diffstat (limited to 'sysdeps/i386/i586/memcopy.h')
| -rw-r--r-- | sysdeps/i386/i586/memcopy.h | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/sysdeps/i386/i586/memcopy.h b/sysdeps/i386/i586/memcopy.h new file mode 100644 index 0000000000..a9bb9e7a40 --- /dev/null +++ b/sysdeps/i386/i586/memcopy.h @@ -0,0 +1,94 @@ +/* memcopy.h -- definitions for memory copy functions. Pentium version. + Copyright (C) 1994 Free Software Foundation, Inc. + Contributed by Torbjorn Granlund (tege@sics.se). + +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 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 +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +/* Get the i386 definitions. We will override some of them below. */ +#include_next <memcopy.h> + + +/* Written like this, the Pentium pipeline can execute the loop at a + sustained rate of 2 instructions/clock, or asymptotically 480 + Mbytes/second at 60Mhz. */ + +#undef WORD_COPY_FWD +#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes) \ + do \ + { \ + asm volatile ("subl $32,%2\n" \ + "js 2f\n" \ + "1:\n" \ + "movl 0(%1),%%eax\n" \ + "movl 4(%1),%%edx\n" \ + "movl %%eax,0(%0)\n" \ + "movl %%edx,4(%0)\n" \ + "movl 8(%1),%%eax\n" \ + "movl 12(%1),%%edx\n" \ + "movl %%eax,8(%0)\n" \ + "movl %%edx,12(%0)\n" \ + "movl 16(%1),%%eax\n" \ + "movl 20(%1),%%edx\n" \ + "movl %%eax,16(%0)\n" \ + "movl %%edx,20(%0)\n" \ + "movl 24(%1),%%eax\n" \ + "movl 28(%1),%%edx\n" \ + "movl %%eax,24(%0)\n" \ + "movl %%edx,28(%0)\n" \ + "addl $32,%1\n" \ + "addl $32,%0\n" \ + "subl $32,%2\n" \ + "jns 1b\n" \ + "2: addl $32,%2" : \ + "=r" (dst_bp), "=r" (src_bp), "=r" (nbytes_left) : \ + "0" (dst_bp), "1" (src_bp), "2" (nbytes) : \ + "ax", "dx"); \ + } while (0) + +#undef WORD_COPY_BWD +#define WORD_COPY_BWD(dst_ep, src_ep, nbytes_left, nbytes) \ + do \ + { \ + asm volatile ("subl $32,%2\n" \ + "js 2f\n" \ + "1:\n" \ + "movl -4(%1),%%eax\n" \ + "movl -8(%1),%%edx\n" \ + "movl %%eax,-4(%0)\n" \ + "movl %%edx,-8(%0)\n" \ + "movl -12(%1),%%eax\n" \ + "movl -16(%1),%%edx\n" \ + "movl %%eax,-12(%0)\n" \ + "movl %%edx,-16(%0)\n" \ + "movl -20(%1),%%eax\n" \ + "movl -24(%1),%%edx\n" \ + "movl %%eax,-20(%0)\n" \ + "movl %%edx,-24(%0)\n" \ + "movl -28(%1),%%eax\n" \ + "movl -32(%1),%%edx\n" \ + "movl %%eax,-28(%0)\n" \ + "movl %%edx,-32(%0)\n" \ + "subl $32,%1\n" \ + "subl $32,%0\n" \ + "subl $32,%2\n" \ + "jns 1b\n" \ + "2: addl $32,%2" : \ + "=r" (dst_bp), "=r" (src_bp), "=r" (nbytes_left) : \ + "0" (dst_bp), "1" (src_bp), "2" (nbytes) : \ + "ax", "dx"); \ + } while (0) |