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14 lines
455 B
ArmAsm
14 lines
455 B
ArmAsm
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.file "memchr.S"
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.section .text
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.global _memchr
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.type _memchr,@function
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_memchr:
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cmp #0, r3 ; If r3 is 0 suntil.b will do nothing and not set any flags...
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stz #1, r1 ; ...so store 1 into r1. It will be decremented by the SUB later.
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suntil.b ; Search until *r1 == r2 or r3 bytes have been examined.
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stnz #1, r1 ; If no match was found return NULL.
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sub #1, r1 ; suntil.b leaves r1 pointing at the address *after* the match.
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rts
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