53 lines
498 B
ArmAsm
53 lines
498 B
ArmAsm
TEXT memcmp(SB),$0
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MOVQ n+16(FP), BX
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CMPQ BX, $0
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JEQ none
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MOVQ RARG, DI
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MOVQ p2+8(FP), SI
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CLD
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MOVQ DI, CX
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ORQ SI, CX
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ANDL $3, CX
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JNE c3
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/*
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* first by longs
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*/
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MOVQ BX, CX
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SHRQ $2, CX
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REP; CMPSL
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JNE found
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/*
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* then by bytes
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*/
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ANDL $3, BX
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c3:
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MOVQ BX, CX
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REP; CMPSB
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JNE found1
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none:
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MOVQ $0, AX
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RET
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/*
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* if long found,
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* back up and look by bytes
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*/
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found:
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MOVL $4, CX
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SUBQ CX, DI
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SUBQ CX, SI
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REP; CMPSB
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found1:
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JLS lt
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MOVQ $-1, AX
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RET
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lt:
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MOVQ $1, AX
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RET
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