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#if defined __thumb__

#include "../../string/strcmp.c"

#else

#include <string.h>

#include "xscale.h"

int

strcmp (const char *s1, const char *s2)

{

  asm (PRELOADSTR ("%0") : : "r" (s1));

  asm (PRELOADSTR ("%0") : : "r" (s2));

#ifndef __OPTIMIZE_SIZE__

  if (((long)s1 & 3) == ((long)s2 & 3))

    {

      int result;

      /* Skip unaligned part.  */

      while ((long)s1 & 3)

        {

          if (*s1 == '\0' || *s1 != *s2)

            goto out;

          s1++;

          s2++;

        }

  /* Load two constants:

     lr = 0xfefefeff [ == ~(0x80808080 << 1) ]

     ip = 0x80808080  */

      asm (

       "ldr     r2, [%1, #0]\n\

        ldr     r3, [%2, #0]\n\

        cmp     r2, r3\n\

        bne     2f\n\

\n\

        mov     ip, #0x80\n\

        add     ip, ip, #0x8000\n\

        add     ip, ip, ip, lsl #16\n\

        mvn     lr, ip, lsl #1\n\

\n\

0:\n\

        ldr     r2, [%1, #0]\n\

        add     r3, r2, lr\n\

        bic     r3, r3, r2\n\

        tst     r3, ip\n\

        beq     1f\n\

        mov     %0, #0x0\n\

        b       3f\n\

1:\n\

        ldr     r2, [%1, #4]!\n\

        ldr     r3, [%2, #4]!\n\

"       PRELOADSTR("%1") "\n\

"       PRELOADSTR("%2") "\n\

        cmp     r2, r3\n\

        beq     0b"

       /* The following part could be done in a C loop as well, but it needs

          to be assembler to save some cycles in the case where the optimized

          loop above finds the strings to be equal.  */

"\n\

2:\n\

        ldrb    r2, [%1, #0]\n\

"       PRELOADSTR("%1") "\n\

"       PRELOADSTR("%2") "\n\

        cmp     r2, #0x0\n\

        beq     1f\n\

        ldrb    r3, [%2, #0]\n\

        cmp     r2, r3\n\

        bne     1f\n\

0:\n\

        ldrb    r3, [%1, #1]!\n\

        add     %2, %2, #1\n\

        ands    ip, r3, #0xff\n\

        beq     1f\n\

        ldrb    r3, [%2]\n\

        cmp     ip, r3\n\

        beq     0b\n\

1:\n\

        ldrb    lr, [%1, #0]\n\

        ldrb    ip, [%2, #0]\n\

        rsb     %0, ip, lr\n\

3:\n\

"

       : "=r" (result), "=&r" (s1), "=&r" (s2)

       : "1" (s1), "2" (s2)

       : "lr", "ip", "r2", "r3", "cc");

      return result;

    }

#endif

  while (*s1 != '\0' && *s1 == *s2)

    {

      asm (PRELOADSTR("%0") : : "r" (s1));

      asm (PRELOADSTR("%0") : : "r" (s2));

      s1++;

      s2++;

    }

 out:

  return (*(unsigned char *) s1) - (*(unsigned char *) s2);

}

#endif