toolchain/gcc/newlib/libc/machine/xscale/strcpy.c

   1 #if defined __thumb__
   2
   3 #include "../../string/strcpy.c"
   4
   5 #else
   6
   7 #include <string.h>
   8 #include "xscale.h"
   9
  10 char *
  11 strcpy (char *dest, const char *src)
  12 {
  13   char *dest0 = dest;
  14
  15   asm (PRELOADSTR ("%0") : : "r" (src));
  16
  17 #ifndef __OPTIMIZE_SIZE__
  18   if (((long)src & 3) == ((long)dest & 3))
  19     {
  20       /* Skip unaligned part.  */
  21       while ((long)src & 3)
  22         {
  23           if (! (*dest++ = *src++))
  24             return dest0;
  25         }
  26
  27   /* Load two constants:
  28      R4 = 0xfefefeff [ == ~(0x80808080 << 1) ]
  29      R5 = 0x80808080  */
  30
  31   asm ("mov     r5, #0x80\n\
  32         ldr     r1, [%1, #0]\n\
  33         add     r5, r5, #0x8000\n\
  34         add     r5, r5, r5, lsl #16\n\
  35         mvn     r4, r5, lsl #1\n\
  36 \n\
  37         add     r3, r1, r5\n\
  38         bic     r3, r3, r1\n\
  39         ands    r2, r3, r4\n\
  40         bne     1f\n\
  41 0:\n\
  42         ldr     r3, [%1, #0]\n\
  43         ldr     r1, [%1, #4]!\n\
  44 "       PRELOADSTR("%1") "\n\
  45         str     r3, [%0], #4\n\
  46         add     r2, r1, r4\n\
  47         bic     r2, r2, r1\n\
  48         ands    r3, r2, r5\n\
  49         beq     0b\n\
  50 1:"
  51        : "=&r" (dest), "=&r" (src)
  52        : "0" (dest), "1" (src)
  53        : "r1", "r2", "r3", "r4", "r5", "memory", "cc");
  54     }
  55 #endif
  56
  57   while (*dest++ = *src++)
  58     asm (PRELOADSTR ("%0") : : "r" (src));
  59   return dest0;
  60 }
  61
  62 #endif