mask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
}

//go:nosplit
func (c *sigctxt) fixsigcode(sig uint32) {
}

func setProcessCPUProfiler(hz int32) {
	setProcessCPUProfilerTimer(hz)
}

func setThreadCPUProfiler(hz int32) {
	setThreadCPUProfilerHz(hz)
}

//go:nosplit
func validSIGPROF(mp *m, c *sigctxt) bool {
	return true
}

func sysargs(argc int32, argv **byte) {
	n := argc + 1

	mask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
}

//go:nosplit
func (c *sigctxt) fixsigcode(sig uint32) {
}

func setProcessCPUProfiler(hz int32) {
	setProcessCPUProfilerTimer(hz)
}

func setThreadCPUProfiler(hz int32) {
	setThreadCPUProfilerHz(hz)
}

//go:nosplit
func validSIGPROF(mp *m, c *sigctxt) bool {
	return true
}

func sysargs(argc int32, argv **byte) {
	n := argc + 1

	*mask |= 1 << (uint32(i) - 1)
}

func sigdelset(mask *sigset, i int) {
	*mask &^= 1 << (uint32(i) - 1)
}

func setProcessCPUProfiler(hz int32) {
	setProcessCPUProfilerTimer(hz)
}

func setThreadCPUProfiler(hz int32) {
	setThreadCPUProfilerHz(hz)
}

//go:nosplit
func validSIGPROF(mp *m, c *sigctxt) bool {
	return true
}

//go:linkname executablePath os.executablePath

	}

	// No active per-thread timer means the only valid profiler is setitimer.
	return setitimer
}

func setProcessCPUProfiler(hz int32) {
	setProcessCPUProfilerTimer(hz)
}

func setThreadCPUProfiler(hz int32) {
	mp := getg().m
	mp.profilehz = hz

	// destroy any active timer
	if mp.profileTimerValid.Load() {
		timerid := mp.profileTimer
		mp.profileTimerValid.Store(false)

	mask.__sigbits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
}

//go:nosplit
func (c *sigctxt) fixsigcode(sig uint32) {
}

func setProcessCPUProfiler(hz int32) {
	setProcessCPUProfilerTimer(hz)
}

func setThreadCPUProfiler(hz int32) {
	setThreadCPUProfilerHz(hz)
}

//go:nosplit
func validSIGPROF(mp *m, c *sigctxt) bool {
	return true
}

//go:nosplit
func semacreate(mp *m) {

	}
}

// setProcessCPUProfilerTimer is called when the profiling timer changes.
// It is called with prof.signalLock held. hz is the new timer, and is 0 if
// profiling is being disabled. Enable or disable the signal as
// required for -buildmode=c-archive.
func setProcessCPUProfilerTimer(hz int32) {
	if hz != 0 {
		// Enable the Go signal handler if not enabled.
		if atomic.Cas(&handlingSig[_SIGPROF], 0, 1) {
			h := getsig(_SIGPROF)

	return string(js)
}

func TestConvertCPUProfileNoSamples(t *testing.T) {
	// A test server with mock cpu profile data.
	var buf bytes.Buffer

	b := []uint64{3, 0, 500} // empty profile at 500 Hz (2ms sample period)
	p, err := translateCPUProfile(b, 1)
	if err != nil {
		t.Fatalf("translateCPUProfile: %v", err)
	}
	if err := p.Write(&buf); err != nil {
		t.Fatalf("writing profile: %v", err)
	}

	if hz > 0 {
		ms = 1000 / hz
		if ms == 0 {
			ms = 1
		}
		due = int64(ms) * -10000
	}
	stdcall6(_SetWaitableTimer, profiletimer, uintptr(unsafe.Pointer(&due)), uintptr(ms), 0, 0, 0)
	atomic.Store((*uint32)(unsafe.Pointer(&getg().m.profilehz)), uint32(hz))
}

const preemptMSupported = true

// suspendLock protects simultaneous SuspendThread operations from
// suspending each other.

	// The runtime routines allow a variable profiling rate,
	// but in practice operating systems cannot trigger signals
	// at more than about 500 Hz, and our processing of the
	// signal is not cheap (mostly getting the stack trace).
	// 100 Hz is a reasonable choice: it is frequent enough to
	// produce useful data, rare enough not to bog down the
	// system, and a nice round number to make it easy to

		<-main_init_done
	}

	// Check whether the profiler needs to be turned on or off; this route to
	// run Go code does not use runtime.execute, so bypasses the check there.
	hz := sched.profilehz
	if gp.m.profilehz != hz {
		setThreadCPUProfiler(hz)
	}

	// Add entry to defer stack in case of panic.
	restore := true
	defer unwindm(&restore)

	if raceenabled {
		raceacquire(unsafe.Pointer(&racecgosync))
	}