i386/string/strcmp.s

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 .text
  24 .globl _strcmp
  25 _strcmp:
  26         movl    0x04(%esp),%eax
  27         movl    0x08(%esp),%edx
  28         jmp     L2                      /* Jump into the loop! */
  29
  30         .align  2,0x90
  31 L1:     incl    %eax
  32         incl    %edx
  33 L2:     movb    (%eax),%cl
  34         testb   %cl,%cl                 /* null terminator??? */
  35         jz      L3
  36         cmpb    %cl,(%edx)              /* chars match??? */
  37         jne     L3
  38         incl    %eax
  39         incl    %edx
  40         movb    (%eax),%cl
  41         testb   %cl,%cl
  42         jz      L3
  43         cmpb    %cl,(%edx)
  44         jne     L3
  45         incl    %eax
  46         incl    %edx
  47         movb    (%eax),%cl
  48         testb   %cl,%cl
  49         jz      L3
  50         cmpb    %cl,(%edx)
  51         jne     L3
  52         incl    %eax
  53         incl    %edx
  54         movb    (%eax),%cl
  55         testb   %cl,%cl
  56         jz      L3
  57         cmpb    %cl,(%edx)
  58         jne     L3
  59         incl    %eax
  60         incl    %edx
  61         movb    (%eax),%cl
  62         testb   %cl,%cl
  63         jz      L3
  64         cmpb    %cl,(%edx)
  65         jne     L3
  66         incl    %eax
  67         incl    %edx
  68         movb    (%eax),%cl
  69         testb   %cl,%cl
  70         jz      L3
  71         cmpb    %cl,(%edx)
  72         jne     L3
  73         incl    %eax
  74         incl    %edx
  75         movb    (%eax),%cl
  76         testb   %cl,%cl
  77         jz      L3
  78         cmpb    %cl,(%edx)
  79         jne     L3
  80         incl    %eax
  81         incl    %edx
  82         movb    (%eax),%cl
  83         testb   %cl,%cl
  84         jz      L3
  85         cmpb    %cl,(%edx)
  86         je      L1
  87         .align 2, 0x90
  88 L3:     movzbl  (%eax),%eax             /* unsigned comparison */
  89         movzbl  (%edx),%edx
  90         subl    %edx,%eax
  91         ret