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Last change
on this file since 444 was
444,
checked in by satin@…, 6 years ago
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add newlib,libalmos-mkh, restructure shared_syscalls.h and mini-libc
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File size:
2.8 KB
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| 1 | /* |
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| 2 | * ==================================================== |
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| 3 | * Copyright (C) 1998, 2002, 2008 by Red Hat Inc. All rights reserved. |
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| 4 | * |
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| 5 | * Permission to use, copy, modify, and distribute this |
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| 6 | * software is freely granted, provided that this notice |
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| 7 | * is preserved. |
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| 8 | * ==================================================== |
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| 9 | */ |
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| 10 | |
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| 11 | #include "i386mach.h" |
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| 12 | |
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| 13 | .global SYM (strchr) |
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| 14 | SOTYPE_FUNCTION(strchr) |
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| 15 | |
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| 16 | SYM (strchr): |
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| 17 | |
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| 18 | #ifdef __iamcu__ |
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| 19 | xorl ecx,ecx |
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| 20 | movb dl,cl |
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| 21 | |
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| 22 | /* loop while (*s && *s++ != c) */ |
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| 23 | leal -1(eax),eax |
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| 24 | L15: |
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| 25 | incl eax |
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| 26 | movb (eax),dl |
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| 27 | testb dl,dl |
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| 28 | je L14 |
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| 29 | cmpb cl,dl |
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| 30 | jne L15 |
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| 31 | |
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| 32 | L14: |
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| 33 | /* if (*s == c) return address otherwise return NULL */ |
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| 34 | cmpb cl,(eax) |
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| 35 | je L19 |
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| 36 | xorl eax,eax |
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| 37 | |
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| 38 | L19: |
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| 39 | ret |
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| 40 | #else |
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| 41 | pushl ebp |
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| 42 | movl esp,ebp |
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| 43 | pushl edi |
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| 44 | pushl ebx |
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| 45 | xorl ebx,ebx |
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| 46 | movl 8(ebp),edi |
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| 47 | addb 12(ebp),bl |
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| 48 | |
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| 49 | #ifndef __OPTIMIZE_SIZE__ |
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| 50 | /* Special case strchr(p,0). */ |
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| 51 | je L25 |
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| 52 | |
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| 53 | /* Do byte-wise checks until string is aligned. */ |
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| 54 | test $3,edi |
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| 55 | je L5 |
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| 56 | movl edi,eax |
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| 57 | movb (eax),cl |
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| 58 | testb cl,cl |
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| 59 | je L14 |
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| 60 | cmpb bl,cl |
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| 61 | je L19 |
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| 62 | incl edi |
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| 63 | |
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| 64 | test $3,edi |
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| 65 | je L5 |
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| 66 | movl edi,eax |
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| 67 | movb (eax),cl |
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| 68 | testb cl,cl |
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| 69 | je L14 |
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| 70 | cmpb bl,cl |
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| 71 | je L19 |
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| 72 | incl edi |
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| 73 | |
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| 74 | test $3,edi |
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| 75 | je L5 |
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| 76 | movl edi,eax |
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| 77 | movb (eax),cl |
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| 78 | testb cl,cl |
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| 79 | je L14 |
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| 80 | cmpb bl,cl |
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| 81 | je L19 |
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| 82 | incl edi |
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| 83 | |
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| 84 | /* create 4 byte mask which is just the desired byte repeated 4 times */ |
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| 85 | L5: |
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| 86 | movl ebx,ecx |
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| 87 | sall $8,ebx |
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| 88 | subl $4,edi |
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| 89 | orl ecx,ebx |
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| 90 | movl ebx,edx |
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| 91 | sall $16,ebx |
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| 92 | orl edx,ebx |
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| 93 | |
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| 94 | /* loop performing 4 byte mask checking for 0 byte or desired byte */ |
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| 95 | .p2align 4,,7 |
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| 96 | L10: |
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| 97 | addl $4,edi |
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| 98 | movl (edi),ecx |
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| 99 | leal -16843009(ecx),edx |
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| 100 | movl ecx,eax |
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| 101 | notl eax |
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| 102 | andl eax,edx |
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| 103 | testl $-2139062144,edx |
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| 104 | jne L9 |
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| 105 | |
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| 106 | xorl ebx,ecx |
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| 107 | leal -16843009(ecx),edx |
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| 108 | notl ecx |
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| 109 | andl ecx,edx |
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| 110 | testl $-2139062144,edx |
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| 111 | je L10 |
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| 112 | #endif /* not __OPTIMIZE_SIZE__ */ |
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| 113 | |
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| 114 | /* loop while (*s && *s++ != c) */ |
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| 115 | L9: |
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| 116 | leal -1(edi),eax |
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| 117 | .p2align 4,,7 |
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| 118 | L15: |
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| 119 | incl eax |
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| 120 | movb (eax),dl |
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| 121 | testb dl,dl |
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| 122 | je L14 |
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| 123 | cmpb bl,dl |
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| 124 | jne L15 |
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| 125 | |
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| 126 | L14: |
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| 127 | /* if (*s == c) return address otherwise return NULL */ |
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| 128 | cmpb bl,(eax) |
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| 129 | je L19 |
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| 130 | xorl eax,eax |
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| 131 | |
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| 132 | L19: |
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| 133 | leal -8(ebp),esp |
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| 134 | popl ebx |
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| 135 | popl edi |
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| 136 | leave |
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| 137 | ret |
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| 138 | |
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| 139 | #ifndef __OPTIMIZE_SIZE__ |
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| 140 | /* Special case strchr(p,0). */ |
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| 141 | #if 0 |
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| 142 | /* Hideous performance on modern machines. */ |
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| 143 | L25: |
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| 144 | cld |
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| 145 | movl $-1,ecx |
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| 146 | xor eax,eax |
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| 147 | repnz |
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| 148 | scasb |
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| 149 | leal -1(edi),eax |
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| 150 | jmp L19 |
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| 151 | #endif |
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| 152 | L25: |
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| 153 | /* Do byte-wise checks until string is aligned. */ |
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| 154 | test $3,edi |
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| 155 | je L26 |
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| 156 | movl edi,eax |
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| 157 | movb (eax),cl |
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| 158 | testb cl,cl |
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| 159 | je L19 |
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| 160 | incl edi |
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| 161 | |
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| 162 | test $3,edi |
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| 163 | je L26 |
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| 164 | movl edi,eax |
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| 165 | movb (eax),cl |
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| 166 | testb cl,cl |
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| 167 | je L19 |
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| 168 | incl edi |
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| 169 | |
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| 170 | test $3,edi |
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| 171 | je L26 |
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| 172 | movl edi,eax |
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| 173 | movb (eax),cl |
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| 174 | testb cl,cl |
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| 175 | je L19 |
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| 176 | incl edi |
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| 177 | |
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| 178 | L26: |
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| 179 | subl $4,edi |
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| 180 | |
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| 181 | /* loop performing 4 byte mask checking for desired 0 byte */ |
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| 182 | .p2align 4,,7 |
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| 183 | L27: |
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| 184 | addl $4,edi |
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| 185 | movl (edi),ecx |
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| 186 | leal -16843009(ecx),edx |
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| 187 | movl ecx,eax |
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| 188 | notl eax |
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| 189 | andl eax,edx |
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| 190 | testl $-2139062144,edx |
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| 191 | je L27 |
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| 192 | |
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| 193 | jmp L9 |
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| 194 | |
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| 195 | #endif /* !__OPTIMIZE_SIZE__ */ |
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| 196 | |
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| 197 | #endif /* __iamcu__ */ |
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