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/*
 * Copyright (C) 2004-2007 Atmel Corporation
 *
 * This file is subject to the terms and conditions of the GNU Lesser General
 * Public License.  See the file "COPYING.LIB" in the main directory of this
 * archive for more details.
 */

#include <features.h>

#define s1 r12
#define s2 r11
#define len r10

       .text
       .global strcmp
       .type   strcmp, @function
       .align  1
strcmp:
       mov     r8, 3
       tst     s1, r8
       brne    .Lunaligned_s1
       tst     s2, r8
       brne    .Lunaligned_s2

1:     ld.w    r8, s1++
       ld.w    r9, s2++
       cp.w    r8, r9
       brne    2f
       tnbz    r8
       brne    1b
       retal   0

2:     bfextu  r12, r8, 24, 8
       bfextu  r11, r9, 24, 8
       sub     r12, r11
       retne   r12
       cp.w    r11, 0
       reteq   0
       bfextu  r12, r8, 16, 8
       bfextu  r11, r9, 16, 8
       sub     r12, r11
       retne   r12
       cp.w    r11, 0
       reteq   0
       bfextu  r12, r8, 8, 8
       bfextu  r11, r9, 8, 8
       sub     r12, r11
       retne   r12
       cp.w    r11, 0
       reteq   0
       bfextu  r12, r8, 0, 8
       bfextu  r11, r9, 0, 8
       sub     r12, r11
       retal   r12

.Lunaligned_s1:
3:     tst     s1, r8
       breq    4f
       ld.ub   r10, s1++
       ld.ub   r9, s2++
       sub     r10, r9
       retne   r10
       cp.w    r9, 0
       brne    3b
       retal   r10

4:     tst     s2, r8
       breq    1b

.Lunaligned_s2:
       /*
        * s1 and s2 can't both be aligned, and unaligned word loads
        * can trigger spurious exceptions if we cross a page boundary.
        * Do it the slow way...
        */
1:     ld.ub   r8, s1++
       ld.ub   r9, s2++
       sub     r8, r9
       retne   r8
       cp.w    r9, 0
       brne    1b
       retal   0

       .size   strcmp, . - strcmp

libc_hidden_def(strcmp)
#ifndef __UCLIBC_HAS_LOCALE__
strong_alias(strcmp, strcoll)
libc_hidden_def(strcoll)
#endif