init = append(init, mkcallstmt1(fn, reflectdata.RangeMapRType(base.Pos, nrange), ha, typecheck.NodAddr(hit)))
		nfor.Cond = ir.NewBinaryExpr(base.Pos, ir.ONE, ir.NewSelectorExpr(base.Pos, ir.ODOT, hit, keysym), typecheck.NodNil())

		fn = typecheck.LookupRuntime("mapiternext", th)
		nfor.Post = mkcallstmt1(fn, typecheck.NodAddr(hit))

	case ir.ORECV:
		// x = <-c; as.Left is x, as.Right.Left is c.
		// order.stmt made sure x is addressable.
		recv := as.Y.(*ir.UnaryExpr)
		recv.X = walkExpr(recv.X, init)

		n1 := typecheck.NodAddr(as.X)
		r := recv.X // the channel
		return mkcall1(chanfn("chanrecv1", 2, r.Type()), nil, init, r, n1)

	case ir.OAPPEND:
		// x = append(...)
		call := as.Y.(*ir.CallExpr)
		if call.Type().Elem().NotInHeap() {

		init.Append(typecheck.Stmt(ir.NewAssignStmt(base.Pos, value, n)))
	}
	if value != nil {
		// The interface data word is &value.
		return typecheck.Expr(typecheck.NodAddr(value))
	}

	// Time to do an allocation. We'll call into the runtime for that.
	fnname, argType, needsaddr := dataWordFuncName(fromType)
	var fn *ir.Name

	var args []ir.Node
	if needsaddr {

		// is handled by walkCompare.
		fn, needsLength := reflectdata.EqFor(t)
		call := ir.NewCallExpr(base.Pos, ir.OCALL, fn, nil)
		call.Args.Append(typecheck.NodAddr(cmpl))
		call.Args.Append(typecheck.NodAddr(cmpr))
		if needsLength {
			call.Args.Append(ir.NewInt(base.Pos, t.Size()))
		}
		res := ir.Node(call)
		if n.Op() != ir.OEQ {
			res = ir.NewUnaryExpr(base.Pos, ir.ONOT, res)
		}

	for i, orig := range origs {
		p := types.NewField(orig.Pos, orig.Sym, orig.Type)
		p.SetIsDDD(orig.IsDDD())
		res[i] = p
	}
	return res
}

// NodAddr returns a node representing &n at base.Pos.
func NodAddr(n ir.Node) *ir.AddrExpr {
	return NodAddrAt(base.Pos, n)
}

// NodAddrAt returns a node representing &n at position pos.
func NodAddrAt(pos src.XPos, n ir.Node) *ir.AddrExpr {

func mapKeyArg(fast int, n, key ir.Node, assigned bool) ir.Node {
	if fast == mapslow {
		// standard version takes key by reference.
		// orderState.expr made sure key is addressable.
		return typecheck.NodAddr(key)
	}
	if assigned {
		// mapassign does distinguish pointer vs. integer key.
		return key
	}
	// mapaccess and mapdelete don't distinguish pointer vs. integer key.
	switch fast {
	case mapfast32ptr:

		return n
	}
	if l.Type().IsArray() {
		if !ir.IsAddressable(n.X) {
			base.Errorf("invalid operation %v (slice of unaddressable value)", n)
			n.SetType(nil)
			return n
		}

		addr := NodAddr(n.X)
		addr.SetImplicit(true)
		n.X = Expr(addr)
		l = n.X
	}
	t := l.Type()
	var tp *types.Type
	if t.IsString() {
		if hasmax {
			base.Errorf("invalid operation %v (3-index slice of string)", n)

		types.CalcSize(tt)
		rcvr := f2.Type.Recv().Type
		if !types.Identical(rcvr, tt) {
			if rcvr.IsPtr() && types.Identical(rcvr.Elem(), tt) {
				checklvalue(n.X, "call pointer method on")
				addr := NodAddr(n.X)
				addr.SetImplicit(true)
				n.X = typecheck(addr, ctxType|ctxExpr)
			} else if tt.IsPtr() && (!rcvr.IsPtr() || rcvr.IsPtr() && rcvr.Elem().NotInHeap()) && types.Identical(tt.Elem(), rcvr) {

			base.Fatalf("mapKeyTemp: key type is not sufficiently aligned, kt=%v nt=%v", kt, nt)
		}
		tmp := o.newTemp(kt, true)
		// *(*nt)(&tmp) = n
		var e ir.Node = typecheck.NodAddr(tmp)
		e = ir.NewConvExpr(pos, ir.OCONVNOP, nt.PtrTo(), e)
		e = ir.NewStarExpr(pos, e)
		o.append(ir.NewAssignStmt(pos, e, n))
		return tmp
	}
}