//go:nosplit
func (bt *bintime) Add(bt2 *bintime) {
	u := bt.frac
	bt.frac += bt2.frac
	if u > bt.frac {
		bt.sec++
	}
	bt.sec += bt2.sec
}

//go:nosplit
func (bt *bintime) AddX(x uint64) {
	u := bt.frac
	bt.frac += x
	if u > bt.frac {
		bt.sec++
	}
}

var (
	// binuptimeDummy is used in binuptime as the address of an atomic.Load, to simulate

		//     ADUFFxxx $offset
		// becomes
		//     $MOV runtime.duffxxx@GOT, $reg
		//     $LEA $offset($reg), $reg
		//     CALL $reg
		// (we use LEAx rather than ADDx because ADDx clobbers
		// flags and duffzero on 386 does not otherwise do so).
		var sym *obj.LSym
		if p.As == obj.ADUFFZERO {
			sym = ctxt.LookupABI("runtime.duffzero", obj.ABIInternal)
		} else {