arch/nios2nommu/lib/string.c

   1 /*--------------------------------------------------------------------
   2  *
   3  * arch/nios2nommu/lib/string.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  * Jan/20/2004          dgt         NiosII
  21  * Jun/09/2004          dgt         Split out memcpy into separate source file
  22  *
  23  ---------------------------------------------------------------------*/
  24
  25 #include <linux/types.h>
  26 #include <linux/autoconf.h>
  27 #include <asm/nios.h>
  28 #include <asm/string.h>
  29
  30 #ifdef __HAVE_ARCH_MEMSET
  31 void * memset(void * s,int c,size_t count)
  32 {
  33
  34     if (count > 8) {
  35         int destptr, charcnt, dwordcnt, fill8reg, wrkrega;
  36         __asm__ __volatile__ (
  37                  // fill8 %3, %5 (c & 0xff)\n\t"
  38                  //
  39             "    slli    %4,    %5,   8\n\t"
  40             "    or      %4,    %4,   %5\n\t"
  41             "    slli    %3,    %4,   16\n\t"
  42             "    or      %3,    %3,   %4\n\t"
  43                  //
  44                  // Word-align %0 (s) if necessary
  45                  //
  46             "    andi    %4,    %0,   0x01\n\t"
  47             "    beq     %4,    zero, 1f\n\t"
  48             "    addi    %1,    %1,   -1\n\t"
  49             "    stb     %3,  0(%0)\n\t"
  50             "    addi    %0,    %0,   1\n\t"
  51             "1:  \n\t"
  52             "    mov     %2,    %1\n\t"
  53                  //
  54                  // Dword-align %0 (s) if necessary
  55                  //
  56             "    andi    %4,    %0,   0x02\n\t"
  57             "    beq     %4,    zero, 2f\n\t"
  58             "    addi    %1,    %1,   -2\n\t"
  59             "    sth     %3,  0(%0)\n\t"
  60             "    addi    %0,    %0,   2\n\t"
  61             "    mov     %2,    %1\n\t"
  62             "2:  \n\t"
  63                  // %1 and %2 are how many more bytes to set
  64                  //
  65             "    srli    %2,    %2,   2\n\t"
  66                  //
  67                  // %2 is how many dwords to set
  68                  //
  69             "3:  ;\n\t"
  70             "    stw     %3,  0(%0)\n\t"
  71             "    addi    %0,    %0,   4\n\t"
  72             "    addi    %2,    %2,   -1\n\t"
  73             "    bne     %2,    zero, 3b\n\t"
  74                  //
  75                  // store residual word and/or byte if necessary
  76                  //
  77             "    andi    %4,    %1,   0x02\n\t"
  78             "    beq     %4,    zero, 4f\n\t"
  79             "    sth     %3,  0(%0)\n\t"
  80             "    addi    %0,    %0,   2\n\t"
  81             "4:  \n\t"
  82                  // store residual byte if necessary
  83                  //
  84             "    andi    %4,    %1,   0x01\n\t"
  85             "    beq     %4,    zero, 5f\n\t"
  86             "    stb     %3,  0(%0)\n\t"
  87             "5:  \n\t"
  88
  89             : "=r" (destptr),               /* %0  Output               */
  90               "=r" (charcnt),               /* %1  Output               */
  91               "=r" (dwordcnt),              /* %2  Output               */
  92               "=r" (fill8reg),              /* %3  Output               */
  93               "=r" (wrkrega)                /* %4  Output               */
  94
  95             : "r" (c & 0xff),               /* %5  Input                */
  96               "0" (s),                      /* %0  Input/Output         */
  97               "1" (count)                   /* %1  Input/Output         */
  98
  99             : "memory"                      /* clobbered                */
 100             );
 101         }
 102         else {
 103         char* xs=(char*)s;
 104         while (count--)
 105                 *xs++ = c;
 106         }
 107         return s;
 108 }
 109 #endif
 110
 111 #ifdef __HAVE_ARCH_MEMMOVE
 112 void * memmove(void * d, const void * s, size_t count)
 113 {
 114     unsigned long dst, src;
 115
 116     if (d < s) {
 117         dst = (unsigned long) d;
 118         src = (unsigned long) s;
 119
 120         if ((count < 8) || ((dst ^ src) & 3))
 121             goto restup;
 122
 123         if (dst & 1) {
 124                 *(char*)dst++=*(char*)src++;
 125             count--;
 126         }
 127         if (dst & 2) {
 128                 *(short*)dst=*(short*)src;
 129             src += 2;
 130             dst += 2;
 131             count -= 2;
 132         }
 133         while (count > 3) {
 134                 *(long*)dst=*(long*)src;
 135             src += 4;
 136             dst += 4;
 137             count -= 4;
 138         }
 139
 140     restup:
 141         while (count--)
 142                 *(char*)dst++=*(char*)src++;
 143     } else {
 144         dst = (unsigned long) d + count;
 145         src = (unsigned long) s + count;
 146
 147         if ((count < 8) || ((dst ^ src) & 3))
 148             goto restdown;
 149
 150         if (dst & 1) {
 151             src--;
 152             dst--;
 153             count--;
 154                 *(char*)dst=*(char*)src;
 155         }
 156         if (dst & 2) {
 157             src -= 2;
 158             dst -= 2;
 159             count -= 2;
 160                 *(short*)dst=*(short*)src;
 161         }
 162         while (count > 3) {
 163             src -= 4;
 164             dst -= 4;
 165             count -= 4;
 166                 *(long*)dst=*(long*)src;
 167         }
 168
 169     restdown:
 170         while (count--) {
 171             src--;
 172             dst--;
 173                 *(char*)dst=*(char*)src;
 174         }
 175     }
 176
 177     return d;
 178
 179 }
 180 #endif