| // Copyright (c) 2018, the R8 project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| package com.android.tools.r8.ir.analysis.type; |
| |
| import com.android.tools.r8.errors.Unreachable; |
| import com.android.tools.r8.graph.DexItemFactory; |
| |
| public abstract class ReferenceTypeElement extends TypeElement { |
| |
| private static class NullElement extends ReferenceTypeElement { |
| |
| NullElement(Nullability nullability) { |
| super(nullability); |
| } |
| |
| @Override |
| public ReferenceTypeElement getOrCreateVariant(Nullability nullability) { |
| return nullability.isNullable() ? NULL_INSTANCE : NULL_BOTTOM_INSTANCE; |
| } |
| |
| private static NullElement create() { |
| return new NullElement(Nullability.definitelyNull()); |
| } |
| |
| private static NullElement createBottom() { |
| return new NullElement(Nullability.bottom()); |
| } |
| |
| @Override |
| public boolean isNullType() { |
| return true; |
| } |
| |
| @Override |
| public String toString() { |
| return nullability.toString() + " " + DexItemFactory.nullValueType.toString(); |
| } |
| |
| @Override |
| public int hashCode() { |
| return System.identityHashCode(this); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (this == o) { |
| return true; |
| } |
| if (!(o instanceof NullElement)) { |
| return false; |
| } |
| return true; |
| } |
| } |
| |
| private static final ReferenceTypeElement NULL_INSTANCE = NullElement.create(); |
| private static final ReferenceTypeElement NULL_BOTTOM_INSTANCE = NullElement.createBottom(); |
| |
| final Nullability nullability; |
| |
| ReferenceTypeElement(Nullability nullability) { |
| this.nullability = nullability; |
| } |
| |
| @Override |
| public Nullability nullability() { |
| return nullability; |
| } |
| |
| static ReferenceTypeElement getNullType() { |
| return NULL_INSTANCE; |
| } |
| |
| public abstract ReferenceTypeElement getOrCreateVariant(Nullability nullability); |
| |
| public TypeElement asMeetWithNotNull() { |
| return getOrCreateVariant(nullability.meet(Nullability.definitelyNotNull())); |
| } |
| |
| public TypeElement asDefinitelyNull() { |
| return getOrCreateVariant(Nullability.definitelyNull()); |
| } |
| |
| public TypeElement asDefinitelyNotNull() { |
| return getOrCreateVariant(Nullability.definitelyNotNull()); |
| } |
| |
| public TypeElement asMaybeNull() { |
| return getOrCreateVariant(Nullability.maybeNull()); |
| } |
| |
| public ReferenceTypeElement joinNullability(Nullability nullability) { |
| return getOrCreateVariant(nullability().join(nullability)); |
| } |
| |
| public ReferenceTypeElement meetNullability(Nullability nullability) { |
| return getOrCreateVariant(nullability().meet(nullability)); |
| } |
| |
| @Override |
| public boolean isReferenceType() { |
| return true; |
| } |
| |
| @Override |
| public ReferenceTypeElement asReferenceType() { |
| return this; |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| throw new Unreachable("Should be implemented on each sub type"); |
| } |
| |
| @Override |
| public int hashCode() { |
| throw new Unreachable("Should be implemented on each sub type"); |
| } |
| } |