appendWalkStmt(init, ir.NewAssignStmt(base.Pos, tmp, val))
	return typecheck.Expr(typecheck.NodAddr(tmp)).(*ir.AddrExpr)
}

// stackTempAddr returns the expression &tmp, where tmp is a newly
// allocated temporary variable of the given type. Statements to
// zero-initialize tmp are appended to init.
func stackTempAddr(init *ir.Nodes, typ *types.Type) *ir.AddrExpr {
	n := typecheck.TempAt(base.Pos, ir.CurFunc, typ)
	n.SetNonMergeable(true)

	hmapType := reflectdata.MapType()
	hint := n.Len

	// var h *hmap
	var h ir.Node
	if n.Esc() == ir.EscNone {
		// Allocate hmap on stack.

		// var hv hmap
		// h = &hv
		h = stackTempAddr(init, hmapType)

		// Allocate one bucket pointed to by hmap.buckets on stack if hint
		// is not larger than BUCKETSIZE. In case hint is larger than
		// BUCKETSIZE runtime.makemap will allocate the buckets on the heap.