}

		getg().m.mallocing--
	})

	startTheWorld(stw)
	return
}

// ShrinkStackAndVerifyFramePointers attempts to shrink the stack of the current goroutine
// and verifies that unwinding the new stack doesn't crash, even if the old
// stack has been freed or reused (simulated via poisoning).
func ShrinkStackAndVerifyFramePointers() {
	before := stackPoisonCopy
	defer func() { stackPoisonCopy = before }()

	if strings.Contains(stk, "<autogenerated>") {
		t.Fatalf("<autogenerated> appears in stack trace:\n%s", stk)
	}
}

func TestStackWrapperStackInlinePanic(t *testing.T) {
	// Test that inline unwinding correctly tracks the callee by creating a
	// stack of the form wrapper -> inlined function -> panic. If we mess up
	// callee tracking, it will look like the wrapper called panic and we'll see
	// the wrapper in the stack trace.

	got := runTestProg(t, "testprogcgo", "SigStack")
	want := "OK\n"
	if got != want {
		t.Errorf("expected %q got %v", want, got)
	}
}

func TestCgoTracebackSigpanic(t *testing.T) {
	// Test unwinding over a sigpanic in C code without a C
	// symbolizer. See issue #23576.
	if runtime.GOOS == "windows" {
		// On Windows if we get an exception in C code, we let
		// the Windows exception handler unwind it, rather

	// but it is called with a special calling convention where
	// the caller doesn't save LR on stack but passes it as a
	// register (R5), and the unwinder currently doesn't understand.
	// Make it SPWRITE to stop unwinding. (See issue 54332)
	// Use OR R0, R1 instead of MOVD R1, R1 as the MOVD instruction
	// has a special affect on Power8,9,10 by lowering the thread 
	// priority and causing a slowdown in execution time

	OR	R0, R1

	// but it is called with a special calling convention where
	// the caller doesn't save LR on stack but passes it as a
	// register (R3), and the unwinder currently doesn't understand.
	// Make it SPWRITE to stop unwinding. (See issue 54332)
	MOVD	RSP, RSP

	MOVW	$0, R26
	B runtime·morestack(SB)

// spillArgs stores return values from registers to a *internal/abi.RegArgs in R20.
TEXT ·spillArgs(SB),NOSPLIT,$0-0

	}

	cleanupDuplicateLocations(p)
	return p, nil
}

func cleanupDuplicateLocations(p *Profile) {
	// The profile handler may duplicate the leaf frame, because it gets
	// its address both from stack unwinding and from the signal
	// context. Detect this and delete the duplicate, which has been
	// adjusted by -1. The leaf address should not be adjusted as it is
	// not a call.
	for _, s := range p.Sample {

	// compile barrier.
	RET

// Save state of caller into g->sched,
// but using fake PC from systemstack_switch.
// Must only be called from functions with no locals ($0)
// or else unwinding from systemstack_switch is incorrect.
TEXT gosave_systemstack_switch<>(SB),NOSPLIT,$0
	PUSHL	AX
	PUSHL	BX
	get_tls(BX)
	MOVL	g(BX), BX
	LEAL	arg+0(FP), AX
	MOVL	AX, (g_sched+gobuf_sp)(BX)

		// where the signal occurred made a call to the
		// function sigpanic. Then set the PC to sigpanic.

		// Have to pass arguments out of band since
		// augmenting the stack frame would break
		// the unwinding code.
		gp.sig = sig
		gp.sigcode0 = uintptr(c.sigcode())
		gp.sigcode1 = c.fault()
		gp.sigpc = c.sigpc()

		c.preparePanic(sig, gp)
		return
	}

	if c.sigFromUser() || flags&_SigNotify != 0 {

// trace as well as any additional frames needed for frame pointer unwinding
// with delayed inline expansion.
func makeProfStackFP() []uintptr {
	// The "1" term is to account for the first stack entry being
	// taken up by a "skip" sentinel value for profilers which
	// defer inline frame expansion until the profile is reported.
	// The "maxSkip" term is for frame pointer unwinding, where we

	p.r(o, o)
}
func (p *A) r(o1, o2 O) {
	switch x := o1.(type) {
	case *IO:
		p.x = int(*x)
	case *OS:
		p.x = int(*x + 2)
	}
}

// see note above about the importance of all this code winding up on one line.