return int64(n)
}

// markrootFreeGStacks frees stacks of dead Gs.
//
// This does not free stacks of dead Gs cached on Ps, but having a few
// cached stacks around isn't a problem.
func markrootFreeGStacks() {
	// Take list of dead Gs with stacks.
	lock(&sched.gFree.lock)
	list := sched.gFree.stack
	sched.gFree.stack = gList{}
	unlock(&sched.gFree.lock)
	if list.empty() {
		return
	}

//
// mcall can only be called from g stacks (not g0, not gsignal).
//
// This must NOT be go:noescape: if fn is a stack-allocated closure,
// fn puts g on a run queue, and g executes before fn returns, the
// closure will be invalidated while it is still executing.
func mcall(fn func(*g))

// systemstack runs fn on a system stack.
// If systemstack is called from the per-OS-thread (g0) stack, or

	BEQ	ZERO, T1, nog

	MOV	A0, m_procid(T0)

	// In child, set up new stack
	MOV	T0, g_m(T1)
	MOV	T1, g

nog:
	// Call fn
	JALR	RA, T2

	// It shouldn't return.  If it does, exit this thread.
	MOV	$111, A0
	MOV	$SYS_exit, A7
	ECALL
	JMP	-3(PC)	// keep exiting

// func sigaltstack(new, old *stackt)
TEXT runtime·sigaltstack(SB),NOSPLIT|NOFRAME,$0
	MOV	new+0(FP), A0

	return handledPaths
}

func (m *PathRecorderMux) trackCallers(path string) {
	stack := string(debug.Stack())
	if existingStack, ok := m.pathStacks[path]; ok {
		utilruntime.HandleError(fmt.Errorf("duplicate path registration of %q: original registration from %v\n\nnew registration from %v", path, existingStack, stack))
	}
	m.pathStacks[path] = stack
}

UserTaskEnd dt=24 task=10 stack=62
UserLog dt=18 task=4 key_string=24 value_string=63 stack=63
UserTaskBegin dt=11 task=12 parent_task=4 name_string=26 stack=64
UserLog dt=21 task=12 key_string=27 value_string=64 stack=65
UserRegionBegin dt=7 task=12 name_string=29 stack=66
GoCreate dt=33 new_g=5 new_stack=17 stack=67
GoCreate dt=12 new_g=6 new_stack=17 stack=67
GoCreate dt=9 new_g=7 new_stack=17 stack=67
GoCreate dt=8 new_g=8 new_stack=17 stack=67

	stw := stopTheWorld(stwWriteHeapDump)

	// Keep m on this G's stack instead of the system stack.
	// Both readmemstats_m and writeheapdump_m have pretty large
	// peak stack depths and we risk blowing the system stack.
	// This is safe because the world is stopped, so we don't
	// need to worry about anyone shrinking and therefore moving
	// our stack.
	var m MemStats
	systemstack(func() {

		if err := p.CheckValid(); err != nil {
			t.Fatalf("invalid profile: %v", err)
		}

		stks := stacks(p)
		for _, test := range tests {
			if !containsStack(stks, test.stk) {
				t.Errorf("No matching stack entry for %v, want %+v", test.name, test.stk)
			}
		}
	})

}

func stacks(p *profile.Profile) (res [][]string) {
	for _, s := range p.Sample {
		var stk []string

	if err != nil {
		t.Skipf("mutex profile is unsupported: %v", err)
	}

	if !seen(p, "mutexHog1") {
		t.Skipf("mutex profile is not working: %v", p)
	}

	// causes mutexHog2 call stacks to appear in the mutex profile.
	done := make(chan bool)
	go func() {
		for {
			mutexHog(20*time.Millisecond, mutexHog2)
			select {
			case <-done:
				done <- true
				return
			default:

		// Stack was deallocated in gfput or just above. Allocate a new one.
		systemstack(func() {
			gp.stack = stackalloc(startingStackSize)
		})
		gp.stackguard0 = gp.stack.lo + stackGuard
	} else {
		if raceenabled {
			racemalloc(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
		}
		if msanenabled {
			msanmalloc(unsafe.Pointer(gp.stack.lo), gp.stack.hi-gp.stack.lo)
		}
		if asanenabled {

// Version of newosproc that doesn't require a valid G.
//
//go:nosplit
func newosproc0(stacksize uintptr, fn unsafe.Pointer) {
	stack := sysAlloc(stacksize, &memstats.stacks_sys)
	if stack == nil {
		writeErrStr(failallocatestack)
		exit(1)
	}
	ret := clone(cloneFlags, unsafe.Pointer(uintptr(stack)+stacksize), nil, nil, fn)
	if ret < 0 {
		writeErrStr(failthreadcreate)
		exit(1)
	}
}

const (