ref: 0c3e5940527272770e2f87127bf76b5dbae7a8bd dir: /sys/src/libc/68000/tas.s/
TEXT _tas(SB), $0 MOVL $0, R0 MOVL a+0(FP), A0 TAS (A0) BEQ tas_1 MOVL $1, R0 tas_1: RTS