// function sigpanic was called from the PC that faulted. It has
	// to be sigpanic, as the stack unwinding code in traceback.go
	// looks explicitly for it.
	//
	// To do this we call into runtime·setsigsegv, which sets the
	// appropriate state inside the g object. We give it the faulting
	// PC on the stack, then put it in the LR before calling sigpanic.

	// Build a 32-byte stack frame for us for this call.

	// Frame pointer unwinding won't visit the sigpanic frame, since
	// sigpanic will save the same frame pointer before calling into a panic
	// function.
	*(*uint64)(unsafe.Pointer(uintptr(sp - goarch.PtrSize))) = c.r29()

	pc := gp.sigpc

	if shouldPushSigpanic(gp, pc, uintptr(c.lr())) {
		// Make it look the like faulting PC called sigpanic.
		c.set_lr(uint64(pc))
	}

		return false
	}
	releasem(mp)
	return true
}

// shouldPushSigpanic reports whether pc should be used as sigpanic's
// return PC (pushing a frame for the call). Otherwise, it should be
// left alone so that LR is used as sigpanic's return PC, effectively
// replacing the top-most frame with sigpanic. This is used by
// preparePanic.
func shouldPushSigpanic(gp *g, pc, lr uintptr) bool {
	if pc == 0 {

func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) }

// preparePanic sets up the stack to look like a call to sigpanic.
func (c *sigctxt) preparePanic(sig uint32, gp *g) {
	// We arrange link, and pc to pretend the panicking
	// function calls sigpanic directly.
	// Always save LINK to stack so that panics in leaf
	// functions are correctly handled. This smashes

func (c *sigctxt) siglr() uintptr { return uintptr(c.lr()) }

// preparePanic sets up the stack to look like a call to sigpanic.
func (c *sigctxt) preparePanic(sig uint32, gp *g) {
	// We arrange lr, and pc to pretend the panicking
	// function calls sigpanic directly.
	// Always save LR to stack so that panics in leaf
	// functions are correctly handled. This smashes

// preparePanic sets up the stack to look like a call to sigpanic.
func (c *sigctxt) preparePanic(sig uint32, gp *g) {
	pc := uintptr(c.eip())
	sp := uintptr(c.esp())

	if shouldPushSigpanic(gp, pc, *(*uintptr)(unsafe.Pointer(sp))) {
		c.pushCall(abi.FuncPCABIInternal(sigpanic), pc)
	} else {
		// Not safe to push the call. Just clobber the frame.
		c.set_eip(uint32(abi.FuncPCABIInternal(sigpanic)))
	}
}

	if shouldPushSigpanic(gp, pc, uintptr(c.link())) {
		// Make it look the like faulting PC called sigpanic.
		c.set_link(uint64(pc))
	}

	// In case we are panicking from external C code
	c.set_r0(0)
	c.set_r30(uint64(uintptr(unsafe.Pointer(gp))))
	c.set_r12(uint64(abi.FuncPCABIInternal(sigpanic)))
	c.set_pc(uint64(abi.FuncPCABIInternal(sigpanic)))
}

func (c *sigctxt) pushCall(targetPC, resumePC uintptr) {

func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) }

// preparePanic sets up the stack to look like a call to sigpanic.
func (c *sigctxt) preparePanic(sig uint32, gp *g) {
	// We arrange RA, and pc to pretend the panicking
	// function calls sigpanic directly.
	// Always save RA to stack so that panics in leaf
	// functions are correctly handled. This smashes

func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) }

// preparePanic sets up the stack to look like a call to sigpanic.
func (c *sigctxt) preparePanic(sig uint32, gp *g) {
	// We arrange link, and pc to pretend the panicking
	// function calls sigpanic directly.
	// Always save LINK to stack so that panics in leaf
	// functions are correctly handled. This smashes

func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) }

// preparePanic sets up the stack to look like a call to sigpanic.
func (c *sigctxt) preparePanic(sig uint32, gp *g) {
	// We arrange link, and pc to pretend the panicking
	// function calls sigpanic directly.
	// Always save LINK to stack so that panics in leaf
	// functions are correctly handled. This smashes