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TEXT strchr(SB), $0
MOVW R1, 0(FP)
MOVB c+7(FP), R4
MOVW s+0(FP), R3
BEQ R4, l2
/*
* char is not null
*/
l1:
MOVB (R3), R1
ADDU $1, R3
BEQ R1, ret
BNE R1,R4, l1
JMP rm1
/*
* char is null
* align to word
*/
l2:
AND $3,R3, R1
BEQ R1, l3
MOVB (R3), R1
ADDU $1, R3
BNE R1, l2
JMP rm1
l3:
MOVW $0xff000000, R6
MOVW $0x00ff0000, R7
l4:
MOVW (R3), R5
ADDU $4, R3
AND R6,R5, R1
AND R7,R5, R2
BEQ R1, b0
AND $0xff00,R5, R1
BEQ R2, b1
AND $0xff,R5, R2
BEQ R1, b2
BNE R2, l4
rm1:
ADDU $-1,R3, R1
JMP ret
b2:
ADDU $-2,R3, R1
JMP ret
b1:
ADDU $-3,R3, R1
JMP ret
b0:
ADDU $-4,R3, R1
JMP ret
ret:
RET
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