case _WAIT_TIMEOUT:
		return -1

	case _WAIT_ABANDONED:
		systemstack(func() {
			throw("runtime.semasleep wait_abandoned")
		})

	case _WAIT_FAILED:
		systemstack(func() {
			print("runtime: waitforsingleobject wait_failed; errno=", getlasterror(), "\n")
			throw("runtime.semasleep wait_failed")
		})

	default:
		systemstack(func() {

	// Do this check last because it is more expensive and rarely true.
	// If it is false the expense doesn't matter since we are crashing.
	if inPersistentAlloc(uintptr(unsafe.Pointer(dst))) {
		return
	}

	systemstack(func() {
		println("write of unpinned Go pointer", hex(uintptr(src)), "to non-Go memory", hex(uintptr(unsafe.Pointer(dst))))
		throw(cgoWriteBarrierFail)
	})
}

	w, _ = w.ensure(1 + traceBytesPerNumber /* traceEvFrequency + frequency */)

	// Write out the string.
	w.byte(byte(traceEvFrequency))
	w.varint(traceClockUnitsPerSecond())

	// Immediately flush the buffer.
	systemstack(func() {
		lock(&trace.lock)
		traceBufFlush(w.traceBuf, gen)
		unlock(&trace.lock)
	})

		// systemstack which clobbers g.sched.
		save(pc, sp, bp)
	}
	if gp.syscallsp < gp.stack.lo || gp.stack.hi < gp.syscallsp {
		systemstack(func() {
			print("entersyscall inconsistent ", hex(gp.syscallsp), " [", hex(gp.stack.lo), ",", hex(gp.stack.hi), "]\n")
			throw("entersyscall")
		})
	}

	if trace.ok() {
		systemstack(func() {
			trace.GoSysCall()

		// If the status was traced, nothing else to do.
		if gp.trace.statusWasTraced(gen) {
			return
		}
		// Scribble down information about this goroutine.
		ug := untracedG{gp: gp, mid: -1}
		systemstack(func() {
			me := getg().m.curg
			// We don't have to handle this G status transition because we
			// already eliminated ourselves from consideration above.

		}

		docrash = dopanic_m(gp, pc, sp)
	})

	if docrash {
		// By crashing outside the above systemstack call, debuggers
		// will not be confused when generating a backtrace.
		// Function crash is marked nosplit to avoid stack growth.
		crash()
	}

	systemstack(func() {
		exit(2)
	})

	*(*int)(nil) = 0 // not reached
}

	// the profiler locks. This reduces potential contention and chances of
	// deadlocks. Since the object must be alive during the call to
	// mProf_Malloc, it's fine to do this non-atomically.
	systemstack(func() {
		setprofilebucket(p, b)
	})
}

// Called when freeing a profiled block.
func mProf_Free(b *bucket, size uintptr) {
	index := (mProfCycle.read() + 1) % uint32(len(memRecord{}.future))

	MOVV	(g_sched+gobuf_sp)(g), R3	// sp = m->g0->sched.sp
	ADDV	$-16, R3
	MOVV	R4, 8(R3)
	MOVV	R0, 0(R3)
	JAL	(R20)
	JMP	runtime·badmcall2(SB)

// systemstack_switch is a dummy routine that systemstack leaves at the bottom
// of the G stack. We need to distinguish the routine that
// lives at the bottom of the G stack from the one that lives
// at the top of the system stack because the one at the top of

	ADDU	$-8, R29	// make room for 1 arg and fake LR
	MOVW	R1, 4(R29)
	MOVW	R0, 0(R29)
	JAL	(R4)
	JMP	runtime·badmcall2(SB)

// systemstack_switch is a dummy routine that systemstack leaves at the bottom
// of the G stack.  We need to distinguish the routine that
// lives at the bottom of the G stack from the one that lives
// at the top of the system stack because the one at the top of

// newcoro creates a new coro containing a
// goroutine blocked waiting to run f
// and returns that coro.
func newcoro(f func(*coro)) *coro {
	c := new(coro)
	c.f = f
	pc := getcallerpc()
	gp := getg()
	systemstack(func() {
		mp := gp.m
		start := corostart
		startfv := *(**funcval)(unsafe.Pointer(&start))
		gp = newproc1(startfv, gp, pc, true, waitReasonCoroutine)

		// Scribble down locked thread state if needed and/or donate