// stack.
//
// Synchronous safe-points are implemented by overloading the stack
// bound check in function prologues. To preempt a goroutine at the
// next synchronous safe-point, the runtime poisons the goroutine's
// stack bound to a value that will cause the next stack bound check
// to fail and enter the stack growth implementation, which will
// detect that it was actually a preemption and redirect to preemption
// handling.
//

			if !overflowed {
				t.Fail()
			}
		}

		for stack, traceSamples := range traceStacks {
			pprofSamples := pprofStacks[stack]
			delete(pprofStacks, stack)
			if traceSamples < pprofSamples {
				t.Logf("execution trace did not include all CPU profile samples for stack %q; %d in profile, %d in trace",
					stack, pprofSamples, traceSamples)
				if !overflowed {
					t.Fail()
				}
			}

			// in sset means v is a store, or already pushed to stack, or already assigned a store number
			continue
		}
		stack = append(stack, v)
		sset.add(v.ID)

		for len(stack) > 0 {
			w := stack[len(stack)-1]
			if storeNumber[w.ID] != 0 {
				stack = stack[:len(stack)-1]
				continue
			}
			if w.Op == OpPhi {
				// Phi value doesn't depend on store in the current block.

			// endless recursion occurs if the cycle is not detected.
			//
			// If x and y were compared before, they must be equal
			// (if they were not, the recursion would have stopped);
			// search the ifacePair stack for the same pair.
			//
			// This is a quadratic algorithm, but in practice these stacks
			// are extremely short (bounded by the nesting depth of interface

//
// 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
// if systemstack is called from the signal handling (gsignal) stack,
// systemstack calls fn directly and returns.

// the stack to the heap, but this requires first having a pointer
// hidden on the stack. Immediately after a stack is scanned, it only
// points to shaded objects, so it's not hiding anything, and the
// shade(*slot) prevents it from hiding any other pointers on its
// stack.
//
// For a detailed description of this barrier and proof of

	{11, "SIGSEGV", "segmentation fault"},
	{12, "SIGUSR2", "user defined signal 2"},
	{13, "SIGPIPE", "broken pipe"},
	{14, "SIGALRM", "alarm clock"},
	{15, "SIGTERM", "terminated"},
	{16, "SIGSTKFLT", "stack fault"},
	{17, "SIGCHLD", "child exited"},
	{18, "SIGCONT", "continued"},
	{19, "SIGSTOP", "stopped (signal)"},
	{20, "SIGTSTP", "stopped"},
	{21, "SIGTTIN", "stopped (tty input)"},

	fn.SetABIWrapper(true)
	fn.SetDupok(true)

	// ABI0-to-ABIInternal wrappers will be mainly loading params from
	// stack into registers (and/or storing stack locations back to
	// registers after the wrapped call); in most cases they won't
	// need to allocate stack space, so it should be OK to mark them
	// as NOSPLIT in these cases. In addition, my assumption is that

		t.Skip("skipping windows specific test")
	}
	testenv.SkipFlaky(t, 22575)
	o := runTestProg(t, "testprogcgo", "StackMemory")
	stackUsage, err := strconv.Atoi(o)
	if err != nil {
		t.Fatalf("Failed to read stack usage: %v", err)
	}
	if expected, got := 100<<10, stackUsage; got > expected {
		t.Fatalf("expected < %d bytes of memory per thread, got %d", expected, got)
	}
}

func TestSigStackSwapping(t *testing.T) {

	return dst
}

// MatchStack assigns the current call stack a change ID.
// If the stack should be printed, MatchStack prints it.
// Then MatchStack reports whether a change at the current call stack should be enabled.
func (m *Matcher) Stack(w Writer) bool {
	if m == nil {
		return true
	}
	return m.stack(w)
}

// stack does the real work for Stack.
// This lets stack's body handle m == nil and potentially be inlined.