ref: 4aca92b895e3359a01c6baa6dceeb4cbc81f3e3d 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