| // 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 ReferenceTypeLatticeElement extends TypeLatticeElement { |
| |
| private static class NullLatticeElement extends ReferenceTypeLatticeElement { |
| |
| NullLatticeElement(Nullability nullability) { |
| super(nullability); |
| } |
| |
| @Override |
| public ReferenceTypeLatticeElement getOrCreateVariant(Nullability nullability) { |
| return nullability.isNullable() ? NULL_INSTANCE : NULL_BOTTOM_INSTANCE; |
| } |
| |
| private static NullLatticeElement create() { |
| return new NullLatticeElement(Nullability.definitelyNull()); |
| } |
| |
| private static NullLatticeElement createBottom() { |
| return new NullLatticeElement(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 NullLatticeElement)) { |
| return false; |
| } |
| return true; |
| } |
| } |
| |
| private static final ReferenceTypeLatticeElement NULL_INSTANCE = NullLatticeElement.create(); |
| private static final ReferenceTypeLatticeElement NULL_BOTTOM_INSTANCE = |
| NullLatticeElement.createBottom(); |
| |
| final Nullability nullability; |
| |
| ReferenceTypeLatticeElement(Nullability nullability) { |
| this.nullability = nullability; |
| } |
| |
| @Override |
| public Nullability nullability() { |
| return nullability; |
| } |
| |
| static ReferenceTypeLatticeElement getNullTypeLatticeElement() { |
| return NULL_INSTANCE; |
| } |
| |
| public abstract ReferenceTypeLatticeElement getOrCreateVariant(Nullability nullability); |
| |
| public TypeLatticeElement asNotNull() { |
| return getOrCreateVariant(Nullability.definitelyNotNull()); |
| } |
| |
| @Override |
| public boolean isReference() { |
| return true; |
| } |
| |
| @Override |
| public ReferenceTypeLatticeElement asReferenceTypeLatticeElement() { |
| 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"); |
| } |
| } |