ref: 899ec4d0b568a6d51a85e5344733a2189a7ba1ec dir: /sys/src/libc/68000/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