ref: 44ce0097b612a1fefd754065bdf8d9d2e5ef60c8 dir: /libkern/getfcr-thumb.s/
TEXT setfcr(SB), $0 RET TEXT getfcr(SB), $0 RET TEXT getfsr(SB), $0 RET TEXT setfsr(SB), $0 RET