freeldr/freeldr/rtl/memcpy.c

   1 /*
   2  *  FreeLoader
   3  *  Copyright (C) 1998-2003  Brian Palmer  <brianp@sginet.com>
   4  *
   5  *  This program is free software; you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation; either version 2 of the License, or
   8  *  (at your option) any later version.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program; if not, write to the Free Software
  17  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20 #include <freeldr.h>
  21
  22 #ifdef __i386__
  23 void *memcpy(void *to, const void *from, size_t count)
  24 {
  25   __asm__( \
  26         "or     %%ecx,%%ecx\n\t"\
  27         "jz     .L1\n\t"        \
  28         "cld\n\t"               \
  29         "rep\n\t"               \
  30         "movsb\n\t"             \
  31         ".L1:\n\t"
  32           :
  33           : "D" (to), "S" (from), "c" (count));
  34   return to;
  35 }
  36 #else
  37 void *memcpy(void *to, const void *from, size_t count)
  38 {
  39         unsigned int    i;
  40         char*                   buf1 = to;
  41         const char*             buf2 = from;
  42
  43         for (i=0; i<count; i++)
  44         {
  45                 buf1[i] = buf2[i];
  46         }
  47
  48         return to;
  49 }
  50 #endif