hash := h.hashPtr(t.Obj())
		targs := t.TypeArgs()
		for i := 0; i < targs.Len(); i++ {
			targ := targs.At(i)
			hash += 2 * h.Hash(targ)
		}
		return hash

	case *types.TypeParam:
		return h.hashTypeParam(t)

	case *types.Tuple:
		return h.hashTuple(t)
	}

	panic(fmt.Sprintf("%T: %v", t, t))
}

func (h Hasher) hashTuple(tuple *types.Tuple) uint32 {
	// See go/types.identicalTypes for rationale.