/* memcopy.h -- definitions for memory copy functions. Pentium version. Copyright (C) 1994-2016 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 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 . */ /* Get the i386 definitions. We will override some of them below. */ #include /* 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" \ "movl 0(%0),%%edx\n" /* alloc dest line */ \ "1:\n" \ "movl 28(%0),%%eax\n" /* alloc dest line */ \ "subl $32,%2\n" /* decr loop count */ \ "movl 0(%1),%%eax\n" /* U pipe */ \ "movl 4(%1),%%edx\n" /* V pipe */ \ "movl %%eax,0(%0)\n" /* U pipe */ \ "movl %%edx,4(%0)\n" /* V pipe */ \ "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" \ "leal 32(%1),%1\n" /* update src ptr */ \ "leal 32(%0),%0\n" /* update dst ptr */ \ "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" \ "movl -4(%0),%%edx\n" \ "1:\n" \ "movl -32(%0),%%eax\n" \ "subl $32,%2\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" \ "leal -32(%1),%1\n" \ "leal -32(%0),%0\n" \ "jns 1b\n" \ "2: addl $32,%2" : \ "=r" (dst_ep), "=r" (src_ep), "=r" (nbytes_left) : \ "0" (dst_ep), "1" (src_ep), "2" (nbytes) : \ "ax", "dx"); \ } while (0)