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Rev | Author | Line No. | Line |
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1627 | serge | 1 | /* memchr() Author: Kees J. Bot */ |
2 | /* 2 Jan 1994 */ |
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3 | |||
4 | /* void *memchr(const void *s, int c, size_t n) */ |
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5 | /* Look for a character in a chunk of memory. */ |
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6 | /* */ |
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7 | #include "asm.h" |
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8 | |||
9 | ENTRY(memchr) |
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10 | push %ebp |
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11 | movl %esp, %ebp |
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12 | push %edi |
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13 | movl 8(%ebp), %edi /* edi = string */ |
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14 | movb 12(%ebp), %al /* The character to look for */ |
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15 | movl 16(%ebp), %ecx /* Length */ |
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16 | cmpb $1, %cl /* 'Z' bit must be clear if ecx = 0 */ |
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17 | cld |
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18 | |||
19 | repne scasb |
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20 | jne failure |
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21 | leal -1(%edi), %eax /* Found */ |
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22 | pop %edi |
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23 | pop %ebp |
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24 | ret |
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25 | failure: |
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26 | xorl %eax, %eax |
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27 | pop %edi |
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28 | pop %ebp |
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29 | ret |