src/main/java/com/android/tools/r8/graph/analysis/ApiModelAnalysis.java

// Copyright (c) 2021, 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.graph.analysis;

import com.android.tools.r8.androidapi.AndroidApiReferenceLevelCache;
import com.android.tools.r8.graph.AppView;
import com.android.tools.r8.graph.DexClassAndMember;
import com.android.tools.r8.graph.DexEncodedMethod;
import com.android.tools.r8.graph.LookupTarget;
import com.android.tools.r8.graph.ProgramDefinition;
import com.android.tools.r8.graph.ProgramField;
import com.android.tools.r8.graph.ProgramMethod;
import com.android.tools.r8.shaking.DefaultEnqueuerUseRegistry;
import com.android.tools.r8.utils.AndroidApiLevel;

public class ApiModelAnalysis extends EnqueuerAnalysis {

  private final AppView<?> appView;
  private final AndroidApiLevel minApiLevel;
  private final AndroidApiReferenceLevelCache referenceLevelCache;

  public ApiModelAnalysis(AppView<?> appView, AndroidApiReferenceLevelCache referenceLevelCache) {
    this.appView = appView;
    this.minApiLevel = appView.options().minApiLevel;
    this.referenceLevelCache = referenceLevelCache;
  }

  @Override
  public void processNewlyLiveField(ProgramField field, ProgramDefinition context) {
    computeApiLevelForDefinition(field);
  }

  @Override
  public void processNewlyLiveMethod(ProgramMethod method, ProgramDefinition context) {
    computeApiLevelForDefinition(method);
  }

  @Override
  public void processTracedCode(ProgramMethod method, DefaultEnqueuerUseRegistry registry) {
    assert registry.getMaxApiReferenceLevel().isGreaterThanOrEqualTo(minApiLevel);
    if (appView.options().apiModelingOptions().tracedMethodApiLevelCallback != null) {
      appView
          .options()
          .apiModelingOptions()
          .tracedMethodApiLevelCallback
          .accept(method.getMethodReference(), registry.getMaxApiReferenceLevel());
    }
    computeApiLevelForDefinition(method);
    method
        .getDefinition()
        .setApiLevelForCode(
            appView.options().apiModelingOptions().enableApiCallerIdentification
                ? registry.getMaxApiReferenceLevel()
                : AndroidApiLevel.UNKNOWN);
  }

  @Override
  public void notifyMarkMethodAsTargeted(ProgramMethod method) {
    computeApiLevelForDefinition(method);
  }

  @Override
  public void notifyMarkFieldAsReachable(ProgramField field) {
    computeApiLevelForDefinition(field);
  }

  @Override
  public void notifyMarkVirtualDispatchTargetAsLive(LookupTarget target) {
    target.accept(
        this::computeApiLevelForDefinition,
        lookupLambdaTarget -> {
          // The implementation method will be assigned an api level when visited.
        });
  }

  @Override
  public void notifyFailedMethodResolutionTarget(DexEncodedMethod method) {
    // We may not trace into failed resolution targets.
    method.setApiLevelForCode(AndroidApiLevel.UNKNOWN);
  }

  private void computeApiLevelForDefinition(DexClassAndMember<?, ?> member) {
    if (!appView.options().apiModelingOptions().enableApiCallerIdentification) {
      member.getDefinition().setApiLevelForDefinition(AndroidApiLevel.UNKNOWN);
      return;
    }
    member
        .getDefinition()
        .setApiLevelForDefinition(
            member
                .getReference()
                .computeApiLevelForReferencedTypes(appView, referenceLevelCache::lookupMax));
  }
}