ref: ff2ebe6cfdacd890a74a6d2f9b0acd062d2633b7
dir: /sys/src/libc/spim/strchr.s/
TEXT strchr(SB), $0 MOVW R1, 0(FP) MOVB c+4(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