ref: 503cdceaf0702703a5f0b5884b109ae20a89f28d 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