ref: 424e9d1636df205f33a5ba977fcb72a38f2beebd dir: /sys/src/libc/arm/getfcr.s/
TEXT setfcr(SB), $0 RET TEXT getfcr(SB), $0 RET TEXT getfsr(SB), $0 RET TEXT setfsr(SB), $0 RET