33 lines
623 B
PHP
33 lines
623 B
PHP
init_crc_table:
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xor edx, edx
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mov edi, crc_table
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.1:
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mov ecx, 8
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mov eax, edx
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.2:
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shr eax, 1
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jnc @f
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xor eax, 0xEDB88320
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@@:
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loop .2
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stosd
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inc dl
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jnz .1
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ret
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crc:
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; in: ecx=size, esi->buffer
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; out: eax=crc
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or eax, -1
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jecxz .end
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.loop:
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movzx edx, al
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xor dl, byte [esi]
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inc esi
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shr eax, 8
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xor eax, [crc_table+edx*4]
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loop .loop
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.end:
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xor eax, -1
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ret
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