ctx.G = id
					state.binding = ctx
				}
			} else if old.Executing() && !new.Executing() {
				if tr.Stack != ev.Stack() {
					// This is a case where the transition is happening to a goroutine that is also executing, so
					// these two stacks should always match.
					e.Errorf("StateTransition.Stack doesn't match Event.Stack")
				}
				ctx := state.binding
				if ctx != nil {
					if ctx.G != id {

		// on another stack. That could confuse callers quite a bit.
		// Instead, we require that initAt and any other function that
		// accepts an sp for the current goroutine (typically obtained by
		// calling getcallersp) must not run on that goroutine's stack but
		// instead on the g0 stack.
		throw("cannot trace user goroutine on its own stack")
	}

	// Set the stack bounds to match the current stack. If we don't
	// actually know how big the stack is, like we don't know how big any
	// scheduling stack is, but we assume there's at least 32 kB. If we
	// can get a more accurate stack bound from pthread, use that, provided
	// it actually contains SP..
	g0.stack.hi = sp + 1024
	g0.stack.lo = sp - 32*1024
	if !signal && _cgo_getstackbound != nil {

	KeepAlive(new)
	KeepAlive(old)
}
func sigprocmask_trampoline()

//go:nosplit
//go:cgo_unsafe_args
func sigaltstack(new *stackt, old *stackt) {
	if new != nil && new.ss_flags&_SS_DISABLE != 0 && new.ss_size == 0 {
		// Despite the fact that Darwin's sigaltstack man page says it ignores the size
		// when SS_DISABLE is set, it doesn't. sigaltstack returns ENOMEM

			}

			if len(stack) > 0 {
				stack += " "
			}
			stack += FmtSprintf("%s:%d", name, line-tiuStart)
		}

		if stack != prevStack {
			prevStack = stack

			t.Logf("tiuTest+%#x: %s", pc-pc1, stack)

			if _, ok := want[stack]; ok {
				want[stack]++
			}
		}
	}

	// Check that we got all the stacks we wanted.
	for stack, count := range want {
		if count == 0 {

//
// 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

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

		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

		// 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 {

	// and without worrying about the stack moving out from under us
	// (because we're on a system stack, not a goroutine stack).
	// The above code could be used directly if already on a system stack,
	// but then the only path through this code would be a rare case on Solaris.
	// Using this code for all "already on system stack" calls exercises it more,
	// which should help keep it correct.
	SUBQ	$16, SP