if gp.lockedm == 0 {
		return nil, plainError("goroutine not locked to thread")
	}

	tid := int(gp.lockedm.ptr().procid)
	if tid == 0 {
		return nil, plainError("missing tid")
	}

	f := efaceOf(&fn)
	if f._type == nil || f._type.Kind_&abi.KindMask != abi.Func {
		return nil, plainError("fn must be a function")
	}
	fv := (*funcval)(f.data)

	a := efaceOf(&stackArgs)

func (e errorAddressString) Addr() uintptr {
	return e.addr
}

// plainError represents a runtime error described a string without
// the prefix "runtime error: " after invoking errorString.Error().
// See Issue #14965.
type plainError string

func (e plainError) RuntimeError() {}

func (e plainError) Error() string {
	return string(e)
}

	typeBitsBulkBarrier(t, uintptr(dst), uintptr(src), t.Size_)
	memmove(dst, src, t.Size_)
}

func closechan(c *hchan) {
	if c == nil {
		panic(plainError("close of nil channel"))
	}

	lock(&c.lock)
	if c.closed != 0 {
		unlock(&c.lock)
		panic(plainError("close of closed channel"))
	}

	if raceenabled {
		callerpc := getcallerpc()
		racewritepc(c.raceaddr(), callerpc, abi.FuncPCABIInternal(closechan))

//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname mapassign_fast64
func mapassign_fast64(t *maptype, h *hmap, key uint64) unsafe.Pointer {
	if h == nil {
		panic(plainError("assignment to entry in nil map"))
	}
	if raceenabled {
		callerpc := getcallerpc()
		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast64))
	}
	if h.flags&hashWriting != 0 {

	ctxt.set_pc(ctxt.pc() + 4)
}

// case 8
func (h *debugCallHandler) debugCallUnsafe(ctxt *sigctxt) {
	sp := ctxt.sp()
	reason := *(*string)(unsafe.Pointer(uintptr(sp) + 8))
	h.err = plainError(reason)
	ctxt.set_pc(ctxt.pc() + 4)
}

// case 16
func (h *debugCallHandler) restoreSigContext(ctxt *sigctxt) {
	// Restore all registers except for pc and sp
	pc, sp := ctxt.pc(), ctxt.sp()

	ctxt.set_pc(ctxt.pc() + 4)
}

// case 8
func (h *debugCallHandler) debugCallUnsafe(ctxt *sigctxt) {
	sp := ctxt.sp()
	reason := *(*string)(unsafe.Pointer(uintptr(sp) + 40))
	h.err = plainError(reason)
	ctxt.set_pc(ctxt.pc() + 4)
}

// case 16
func (h *debugCallHandler) restoreSigContext(ctxt *sigctxt) {
	// Restore all registers except for pc and sp
	pc, sp := ctxt.pc(), ctxt.sp()

}

// case 8
func (h *debugCallHandler) debugCallUnsafe(ctxt *sigctxt) {
	rsp := ctxt.rsp()
	reason := *(*string)(unsafe.Pointer(uintptr(rsp)))
	h.err = plainError(reason)
}

// case 16
func (h *debugCallHandler) restoreSigContext(ctxt *sigctxt) {
	// Restore all registers except RIP and RSP.
	rip, rsp := ctxt.rip(), ctxt.rsp()
	fp := ctxt.regs().fpstate

//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname mapassign_fast32
func mapassign_fast32(t *maptype, h *hmap, key uint32) unsafe.Pointer {
	if h == nil {
		panic(plainError("assignment to entry in nil map"))
	}
	if raceenabled {
		callerpc := getcallerpc()
		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_fast32))
	}
	if h.flags&hashWriting != 0 {

	}
	goto retc

retc:
	if caseReleaseTime > 0 {
		blockevent(caseReleaseTime-t0, 1)
	}
	return casi, recvOK

sclose:
	// send on closed channel
	selunlock(scases, lockorder)
	panic(plainError("send on closed channel"))
}

func (c *hchan) sortkey() uintptr {
	return uintptr(unsafe.Pointer(c))
}

// A runtimeSelect is a single case passed to rselect.

//
// Do not remove or change the type signature.
// See go.dev/issue/67401.
//
//go:linkname mapassign_faststr
func mapassign_faststr(t *maptype, h *hmap, s string) unsafe.Pointer {
	if h == nil {
		panic(plainError("assignment to entry in nil map"))
	}
	if raceenabled {
		callerpc := getcallerpc()
		racewritepc(unsafe.Pointer(h), callerpc, abi.FuncPCABIInternal(mapassign_faststr))
	}
	if h.flags&hashWriting != 0 {