ref: 674e690e758a7c251aef64489b1fcf0144f6bb61 dir: /sys/src/libc/386/387/sin.s/
TEXT sin(SB), $0 FMOVD a+0(FP), F0 FSIN RET TEXT cos(SB), $0 FMOVD a+0(FP), F0 FCOS RET