memcmp.S 1.9 KB

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  1. /*
  2. * Copyright (c) 2002 ARM Ltd
  3. * All rights reserved.
  4. *
  5. * Redistribution and use in source and binary forms, with or without
  6. * modification, are permitted provided that the following conditions
  7. * are met:
  8. * 1. Redistributions of source code must retain the above copyright
  9. * notice, this list of conditions and the following disclaimer.
  10. * 2. Redistributions in binary form must reproduce the above copyright
  11. * notice, this list of conditions and the following disclaimer in the
  12. * documentation and/or other materials provided with the distribution.
  13. * 3. The name of the company may not be used to endorse or promote
  14. * products derived from this software without specific prior written
  15. * permission.
  16. *
  17. * THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
  18. * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  19. * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20. * IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21. * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  22. * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  23. * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  24. * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  25. * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  26. * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27. *
  28. * Adapted for uClibc from NetBSD memcmp.S, version 1.2 2003/04/05
  29. * by Erik Andersen <andersen@codepoet.org>
  30. */
  31. .global memcmp
  32. .set memcmp,__memcmp
  33. .text
  34. .global __memcmp
  35. .hidden __memcmp
  36. .type __memcmp,%function
  37. .align 4
  38. __memcmp:
  39. /* if ((len - 1) < 0) return 0 */
  40. subs r2, r2, #1
  41. movmi r0, #0
  42. movmi pc, lr
  43. /* ip == last src address to compare */
  44. add ip, r0, r2
  45. 1:
  46. ldrb r2, [r0], #1
  47. ldrb r3, [r1], #1
  48. cmp ip, r0
  49. cmpcs r2, r3
  50. beq 1b
  51. sub r0, r2, r3
  52. mov pc, lr
  53. .size __memcmp,.-__memcmp
  54. .weak bcmp ; bcmp = memcmp