arch/nios2nommu/lib/memcpy.c

   1 /*--------------------------------------------------------------------
   2  *
   3  * arch/nios2nommu/lib/memcpy.c
   4  *
   5  * Derived from various works, Alpha, ix86, M68K, Sparc, ...et al
   6  *
   7  * Copyright (C) 2004   Microtronix Datacom Ltd
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  *
  20  * Jun/09/2004          dgt         Split out separate source file from string.c
  21  *
  22  ---------------------------------------------------------------------*/
  23
  24 #include <linux/types.h>
  25 #include <linux/autoconf.h>
  26 #include <asm/nios.h>
  27 #include <asm/string.h>
  28
  29 #ifdef __HAVE_ARCH_MEMCPY
  30   void * memcpy(void * d, const void * s, size_t count)
  31    {
  32     unsigned long dst, src;
  33         dst = (unsigned long) d;
  34         src = (unsigned long) s;
  35
  36         if ((count < 8) || ((dst ^ src) & 3))
  37             goto restup;
  38
  39         if (dst & 1) {
  40                 *(char*)dst++=*(char*)src++;
  41             count--;
  42         }
  43         if (dst & 2) {
  44                 *(short*)dst=*(short*)src;
  45             src += 2;
  46             dst += 2;
  47             count -= 2;
  48         }
  49         while (count > 3) {
  50                 *(long*)dst=*(long*)src;
  51             src += 4;
  52             dst += 4;
  53             count -= 4;
  54         }
  55
  56     restup:
  57         while (count--)
  58                 *(char*)dst++=*(char*)src++;
  59
  60         return d;
  61    }
  62 #endif