arch/blackfin/lib/strcmp.S

   1 /*
   2  * Copyright 2005-2010 Analog Devices Inc.
   3  *
   4  * Licensed under the Clear BSD license or the GPL-2 (or later)
   5  */
   6
   7 #include <linux/linkage.h>
   8
   9 /* void *strcmp(char *s1, const char *s2);
  10  * R0 = address (s1)
  11  * R1 = address (s2)
  12  *
  13  * Returns an integer less than, equal to, or greater than zero if s1
  14  *  (or the first n  bytes thereof) is found, respectively, to be less
  15  *  than, to match, or be greater than s2.
  16  */
  17
  18 #ifdef CONFIG_STRCMP_L1
  19 .section .l1.text
  20 #else
  21 .text
  22 #endif
  23
  24 .align 2
  25
  26 ENTRY(_strcmp)
  27         P0 = R0 ;       /* s1 */
  28         P1 = R1 ;       /* s2 */
  29
  30 1:
  31         R0 = B[P0++] (Z);      /* get *s1 */
  32         R1 = B[P1++] (Z);      /* get *s2 */
  33         CC = R0 == R1;         /* compare a byte */
  34         if ! cc jump 2f;       /* not equal, break out */
  35         CC = R0;               /* at end of s1? */
  36         if cc jump 1b (bp);    /* no, keep going */
  37         jump.s 3f;             /* strings are equal */
  38 2:
  39         R0 = R0 - R1;          /* *s1 - *s2 */
  40 3:
  41         RTS;
  42
  43 ENDPROC(_strcmp)