src/main/java/com/android/tools/r8/ir/analysis/value/SingleStringValue.java

// Copyright (c) 2019, 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.value;

import static com.android.tools.r8.ir.analysis.type.Nullability.definitelyNotNull;
import static com.android.tools.r8.ir.analysis.type.TypeElement.stringClassType;

import com.android.tools.r8.graph.AppInfoWithClassHierarchy;
import com.android.tools.r8.graph.AppView;
import com.android.tools.r8.graph.DexString;
import com.android.tools.r8.graph.DexType;
import com.android.tools.r8.graph.ProgramMethod;
import com.android.tools.r8.graph.lens.GraphLens;
import com.android.tools.r8.graph.proto.ArgumentInfoCollection;
import com.android.tools.r8.ir.analysis.type.TypeElement;
import com.android.tools.r8.ir.code.ConstString;
import com.android.tools.r8.ir.code.Instruction;
import com.android.tools.r8.ir.code.MaterializingInstructionsInfo;
import com.android.tools.r8.ir.code.ValueFactory;
import com.android.tools.r8.ir.optimize.info.field.InstanceFieldInitializationInfo;
import com.android.tools.r8.shaking.AppInfoWithLiveness;

public class SingleStringValue extends SingleConstValue {

  private final DexString string;

  /** Intentionally package private, use {@link AbstractValueFactory} instead. */
  SingleStringValue(DexString string) {
    this.string = string;
  }

  @Override
  public boolean hasSingleMaterializingInstruction() {
    return true;
  }

  @Override
  public boolean isSingleStringValue() {
    return true;
  }

  @Override
  public SingleStringValue asSingleStringValue() {
    return this;
  }

  public DexString getDexString() {
    return string;
  }

  @Override
  public boolean equals(Object o) {
    return this == o;
  }

  @Override
  public int hashCode() {
    return string.hashCode();
  }

  @Override
  public String toString() {
    return "SingleStringValue(" + string + ")";
  }

  @Override
  public Instruction[] createMaterializingInstructions(
      AppView<?> appView,
      ProgramMethod context,
      ValueFactory valueFactory,
      MaterializingInstructionsInfo info) {
    TypeElement stringType = stringClassType(appView, definitelyNotNull());
    assert stringType.lessThanOrEqual(info.getOutType(), appView);
    ConstString constString =
        ConstString.builder()
            .setFreshOutValue(valueFactory, stringType, info.getLocalInfo())
            .setPosition(info.getPosition())
            .setValue(string)
            .build();
    assert !constString.instructionInstanceCanThrow(appView, context);
    return new Instruction[] {constString};
  }

  @Override
  boolean internalIsMaterializableInContext(
      AppView<? extends AppInfoWithClassHierarchy> appView, ProgramMethod context) {
    return true;
  }

  @Override
  public boolean isMaterializableInAllContexts(AppView<AppInfoWithLiveness> appView) {
    return true;
  }

  @Override
  public InstanceFieldInitializationInfo fixupAfterParametersChanged(
      ArgumentInfoCollection argumentInfoCollection) {
    return this;
  }

  @Override
  public SingleValue rewrittenWithLens(
      AppView<AppInfoWithLiveness> appView, DexType newType, GraphLens lens, GraphLens codeLens) {
    return this;
  }
}