prof.stack[2] = 0
		return
	}

	var nstk int
	gp := getg()
	sp := getcallersp()
	pc := getcallerpc()
	systemstack(func() {
		var u unwinder
		u.initAt(pc, sp, 0, gp, unwindSilentErrors|unwindJumpStack)
		nstk = 1 + tracebackPCs(&u, skip, prof.stack[1:])
	})
	if nstk < len(prof.stack) {
		prof.stack[nstk] = 0
	}
}

	// Force SPWRITE. This function doesn't actually write SP,
	// 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)
	MOVV    R3, R3

	MOVV	R0, REGCTXT
	JMP	runtime·morestack(SB)

	// Force SPWRITE. This function doesn't actually write SP,
	// 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)
	MOVW	R29, R29

	MOVW	R0, REGCTXT
	JMP	runtime·morestack(SB)

// reflectcall: call a function with the given argument list

	// Force SPWRITE. This function doesn't actually write SP,
	// 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)
	MOVW	R13, R13

	MOVW	$0, R7
	B runtime·morestack(SB)

// reflectcall: call a function with the given argument list

	gp.stack = new
	gp.stackguard0 = new.lo + stackGuard // NOTE: might clobber a preempt request
	gp.sched.sp = new.hi - used
	gp.stktopsp += adjinfo.delta

	// Adjust pointers in the new stack.
	var u unwinder
	for u.init(gp, 0); u.valid(); u.next() {
		adjustframe(&u.frame, &adjinfo)
	}

	// free old stack
	if stackPoisonCopy != 0 {
		fillstack(old, 0xfc)
	}
	stackfree(old)
}

			// stack trace, and there only the real PCs are printed, not the virtual ones.
			// So check to see if the implied virtual PC for this PC (obtained from the
			// unwinder itself) is the next PC in ci.callers. If not, insert it.
			// The +1 here correspond to the pc-- above: the output of Callers
			// and therefore the input to CallersFrames is return PCs from the stack;

	if p.lr == 0 {
		return false
	}

	gp := getg()
	systemstack(func() {
		var limit uintptr
		if d := gp._defer; d != nil {
			limit = d.sp
		}

		var u unwinder
		u.initAt(p.lr, uintptr(p.fp), 0, gp, 0)
		for {
			if !u.valid() {
				p.lr = 0
				return // ok == false
			}

			// TODO(mdempsky): If we populate u.frame.fn.deferreturn for

	// Force SPWRITE. This function doesn't actually write SP,
	// 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 

	if gp.sched.ctxt != nil {
		scanblock(uintptr(unsafe.Pointer(&gp.sched.ctxt)), goarch.PtrSize, &oneptrmask[0], gcw, &state)
	}

	// Scan the stack. Accumulate a list of stack objects.
	var u unwinder
	for u.init(gp, 0); u.valid(); u.next() {
		scanframeworker(&u.frame, &state, gcw)
	}

	// Find additional pointers that point into the stack from the heap.

	// Force SPWRITE. This function doesn't actually write SP,
	// 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)