ref: 33b8e6bd2bce18fc68a89d5e5d73f7f0d5717e40 dir: /sys/src/libc/68020/memchr.s/
TEXT memchr(SB),$0 MOVL n+8(FP),R0 BEQ ret MOVL s1+0(FP),A1 MOVL c+4(FP),R1 l1: CMPB R1,(A1)+ BEQ eq SUBL $1,R0 BNE l1 RTS eq: MOVL A1,R0 SUBL $1,R0 ret: RTS