// Copyright (c) 2017, 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.optimize;

import static com.android.tools.r8.ir.analysis.type.Nullability.definitelyNotNull;
import static com.android.tools.r8.ir.optimize.SimpleDominatingEffectAnalysis.canInlineWithoutSynthesizingNullCheckForReceiver;
import static com.android.tools.r8.utils.MapUtils.ignoreKey;
import static com.google.common.base.Predicates.not;

import com.android.tools.r8.androidapi.AvailableApiExceptions;
import com.android.tools.r8.graph.AccessFlags;
import com.android.tools.r8.graph.AppView;
import com.android.tools.r8.graph.DexClass;
import com.android.tools.r8.graph.DexClassAndMember;
import com.android.tools.r8.graph.DexClassAndMethod;
import com.android.tools.r8.graph.DexEncodedMethod;
import com.android.tools.r8.graph.DexItemFactory;
import com.android.tools.r8.graph.DexMethod;
import com.android.tools.r8.graph.DexProgramClass;
import com.android.tools.r8.graph.DexType;
import com.android.tools.r8.graph.MethodResolutionResult.SingleResolutionResult;
import com.android.tools.r8.graph.NestMemberClassAttribute;
import com.android.tools.r8.graph.ProgramMethod;
import com.android.tools.r8.ir.analysis.ClassInitializationAnalysis;
import com.android.tools.r8.ir.analysis.proto.ProtoInliningReasonStrategy;
import com.android.tools.r8.ir.analysis.type.Nullability;
import com.android.tools.r8.ir.analysis.type.TypeElement;
import com.android.tools.r8.ir.code.BasicBlock;
import com.android.tools.r8.ir.code.BasicBlockIterator;
import com.android.tools.r8.ir.code.CatchHandlers.CatchHandler;
import com.android.tools.r8.ir.code.ConstClass;
import com.android.tools.r8.ir.code.IRCode;
import com.android.tools.r8.ir.code.InitClass;
import com.android.tools.r8.ir.code.Instruction;
import com.android.tools.r8.ir.code.InstructionIterator;
import com.android.tools.r8.ir.code.InstructionListIterator;
import com.android.tools.r8.ir.code.Invoke;
import com.android.tools.r8.ir.code.InvokeMethod;
import com.android.tools.r8.ir.code.InvokeVirtual;
import com.android.tools.r8.ir.code.Monitor;
import com.android.tools.r8.ir.code.MonitorType;
import com.android.tools.r8.ir.code.MoveException;
import com.android.tools.r8.ir.code.Phi;
import com.android.tools.r8.ir.code.Position;
import com.android.tools.r8.ir.code.Throw;
import com.android.tools.r8.ir.code.Value;
import com.android.tools.r8.ir.conversion.IRConverter;
import com.android.tools.r8.ir.conversion.LensCodeRewriter;
import com.android.tools.r8.ir.conversion.MethodProcessor;
import com.android.tools.r8.ir.conversion.OneTimeMethodProcessor;
import com.android.tools.r8.ir.conversion.PostMethodProcessor;
import com.android.tools.r8.ir.optimize.SimpleDominatingEffectAnalysis.SimpleEffectAnalysisResult;
import com.android.tools.r8.ir.optimize.info.OptimizationFeedback;
import com.android.tools.r8.ir.optimize.inliner.DefaultInliningReasonStrategy;
import com.android.tools.r8.ir.optimize.inliner.InliningIRProvider;
import com.android.tools.r8.ir.optimize.inliner.InliningReasonStrategy;
import com.android.tools.r8.ir.optimize.inliner.NopWhyAreYouNotInliningReporter;
import com.android.tools.r8.ir.optimize.inliner.WhyAreYouNotInliningReporter;
import com.android.tools.r8.ir.optimize.membervaluepropagation.R8MemberValuePropagation;
import com.android.tools.r8.shaking.AppInfoWithLiveness;
import com.android.tools.r8.shaking.KeepMethodInfo;
import com.android.tools.r8.shaking.MainDexInfo;
import com.android.tools.r8.utils.ConsumerUtils;
import com.android.tools.r8.utils.InternalOptions;
import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
import com.android.tools.r8.utils.IteratorUtils;
import com.android.tools.r8.utils.ListUtils;
import com.android.tools.r8.utils.Timing;
import com.android.tools.r8.utils.collections.LongLivedProgramMethodSetBuilder;
import com.android.tools.r8.utils.collections.ProgramMethodMap;
import com.android.tools.r8.utils.collections.ProgramMethodSet;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Sets;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Deque;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.function.Consumer;
import java.util.stream.Collectors;

public class Inliner {

  protected final AppView<AppInfoWithLiveness> appView;
  private final IRConverter converter;
  private final LensCodeRewriter lensCodeRewriter;
  final MainDexInfo mainDexInfo;

  // The set of callers of single caller methods where the single caller method could not be inlined
  // due to not being processed at the time of inlining.
  private final LongLivedProgramMethodSetBuilder<ProgramMethodSet> singleInlineCallers;

  private final MultiCallerInliner multiCallerInliner;

  // The set of methods that have been single caller inlined in the current wave. These need to be
  // pruned when the wave ends.
  private final Map<DexProgramClass, ProgramMethodMap<ProgramMethod>>
      singleCallerInlinedMethodsInWave = new ConcurrentHashMap<>();
  private final Set<DexMethod> singleCallerInlinedPrunedMethodsForTesting =
      Sets.newIdentityHashSet();

  private final AvailableApiExceptions availableApiExceptions;

  public Inliner(AppView<AppInfoWithLiveness> appView) {
    this(appView, null);
  }

  public Inliner(AppView<AppInfoWithLiveness> appView, IRConverter converter) {
    this(appView, converter, null);
  }

  public Inliner(
      AppView<AppInfoWithLiveness> appView,
      IRConverter converter,
      LensCodeRewriter lensCodeRewriter) {
    this.appView = appView;
    this.converter = converter;
    this.lensCodeRewriter = lensCodeRewriter;
    this.mainDexInfo = appView.appInfo().getMainDexInfo();
    this.multiCallerInliner = new MultiCallerInliner(appView);
    this.singleInlineCallers =
        LongLivedProgramMethodSetBuilder.createConcurrentForIdentitySet(appView.graphLens());
    availableApiExceptions =
        appView.options().canHaveDalvikCatchHandlerVerificationBug()
            ? new AvailableApiExceptions(appView.options())
            : null;
  }

  public WhyAreYouNotInliningReporter createWhyAreYouNotInliningReporter(
      ProgramMethod singleTarget, ProgramMethod context) {
    return WhyAreYouNotInliningReporter.createFor(singleTarget, appView, context);
  }

  public LensCodeRewriter getLensCodeRewriter() {
    return lensCodeRewriter;
  }

  @SuppressWarnings("ReferenceEquality")
  private ConstraintWithTarget instructionAllowedForInlining(
      Instruction instruction, InliningConstraints inliningConstraints, ProgramMethod context) {
    ConstraintWithTarget result = instruction.inliningConstraint(inliningConstraints, context);
    if (result.isNever() && instruction.isDebugInstruction()) {
      return ConstraintWithTarget.ALWAYS;
    }
    return result;
  }

  @SuppressWarnings("ReferenceEquality")
  public ConstraintWithTarget computeInliningConstraint(IRCode code) {
    InternalOptions options = appView.options();
    if (!options.inlinerOptions().enableInlining) {
      return ConstraintWithTarget.NEVER;
    }
    ProgramMethod method = code.context();
    DexEncodedMethod definition = method.getDefinition();
    if (definition.isClassInitializer() || method.getOrComputeReachabilitySensitive(appView)) {
      return ConstraintWithTarget.NEVER;
    }
    KeepMethodInfo keepInfo = appView.getKeepInfo(method);
    if (!keepInfo.isInliningAllowed(options) && !keepInfo.isClassInliningAllowed(options)) {
      return ConstraintWithTarget.NEVER;
    }

    if (containsPotentialCatchHandlerVerificationError(code)) {
      return ConstraintWithTarget.NEVER;
    }

    ProgramMethod context = code.context();
    if (appView.options().canHaveDalvikIntUsedAsNonIntPrimitiveTypeBug()
        && returnsIntAsBoolean(code, context)) {
      return ConstraintWithTarget.NEVER;
    }

    ConstraintWithTarget result = ConstraintWithTarget.ALWAYS;
    InliningConstraints inliningConstraints = new InliningConstraints(appView);
    for (Instruction instruction : code.instructions()) {
      ConstraintWithTarget state =
          instructionAllowedForInlining(instruction, inliningConstraints, context);
      if (state.isNever()) {
        result = state;
        break;
      }
      // TODO(b/128967328): we may need to collect all meaningful constraints.
      result = ConstraintWithTarget.meet(result, state, appView);
    }
    return result;
  }

  private boolean returnsIntAsBoolean(IRCode code, ProgramMethod method) {
    DexType returnType = method.getDefinition().returnType();
    for (BasicBlock basicBlock : code.blocks) {
      InstructionIterator instructionIterator = basicBlock.iterator();
      while (instructionIterator.hasNext()) {
        Instruction instruction = instructionIterator.nextUntil(Instruction::isReturn);
        if (instruction != null) {
          if (returnType.isBooleanType() && !instruction.inValues().get(0).knownToBeBoolean()) {
            return true;
          }
        }
      }
    }
    return false;
  }

  public void recordCallEdgesForMultiCallerInlining(
      ProgramMethod method, IRCode code, MethodProcessor methodProcessor, Timing timing) {
    multiCallerInliner.recordCallEdgesForMultiCallerInlining(method, code, methodProcessor, timing);
  }

  /**
   * Encodes the constraints for inlining a method's instructions into a different context.
   * <p>
   * This only takes the instructions into account and not whether a method should be inlined or
   * what reason for inlining it might have. Also, it does not take the visibility of the method
   * itself into account.
   */
  public enum Constraint {
    // The ordinal values are important so please do not reorder.
    // Each constraint includes all constraints <= to it.
    // For example, SAMENEST with class X means:
    // - the target is in the same nest as X, or
    // - the target has the same class as X (SAMECLASS <= SAMENEST).
    // SUBCLASS with class X means:
    // - the target is a subclass of X in different package, or
    // - the target is in the same package (PACKAGE <= SUBCLASS), or
    // ...
    // - the target is the same class as X (SAMECLASS <= SUBCLASS).
    NEVER(1), // Never inline this.
    SAMECLASS(2), // Inlineable into methods in the same holder.
    SAMENEST(4), // Inlineable into methods with same nest.
    PACKAGE(8), // Inlineable into methods with holders from the same package.
    SUBCLASS(16), // Inlineable into methods with holders from a subclass in a different package.
    ALWAYS(32); // No restrictions for inlining this.

    final int value;

    Constraint(int value) {
      this.value = value;
    }

    static {
      assert NEVER.ordinal() < SAMECLASS.ordinal();
      assert SAMECLASS.ordinal() < SAMENEST.ordinal();
      assert SAMENEST.ordinal() < PACKAGE.ordinal();
      assert PACKAGE.ordinal() < SUBCLASS.ordinal();
      assert SUBCLASS.ordinal() < ALWAYS.ordinal();
    }

    public Constraint meet(Constraint otherConstraint) {
      if (this.ordinal() < otherConstraint.ordinal()) {
        return this;
      }
      return otherConstraint;
    }

    public boolean isAlways() {
      return this == ALWAYS;
    }

    public boolean isNever() {
      return this == NEVER;
    }

    boolean isSet(int value) {
      return (this.value & value) != 0;
    }
  }

  /**
   * Encodes the constraints for inlining, along with the target holder.
   * <p>
   * Constraint itself cannot determine whether or not the method can be inlined if instructions in
   * the method have different constraints with different targets. For example,
   *   SUBCLASS of x.A v.s. PACKAGE of y.B
   * Without any target holder information, min of those two Constraints is PACKAGE, meaning that
   * the current method can be inlined to any method whose holder is in package y. This could cause
   * an illegal access error due to protect members in x.A. Because of different target holders,
   * those constraints should not be combined.
   * <p>
   * Instead, a right constraint for inlining constraint for the example above is: a method whose
   * holder is a subclass of x.A _and_ in the same package of y.B can inline this method.
   */
  public static class ConstraintWithTarget {
    public final Constraint constraint;
    // Note that this is not context---where this constraint is encoded.
    // It literally refers to the holder type of the target, which could be:
    // invoked method in invocations, field in field instructions, type of check-cast, etc.
    final DexType targetHolder;

    public static final ConstraintWithTarget NEVER = new ConstraintWithTarget(Constraint.NEVER);
    public static final ConstraintWithTarget ALWAYS = new ConstraintWithTarget(Constraint.ALWAYS);

    private ConstraintWithTarget(Constraint constraint) {
      assert constraint == Constraint.NEVER || constraint == Constraint.ALWAYS;
      this.constraint = constraint;
      this.targetHolder = null;
    }

    ConstraintWithTarget(Constraint constraint, DexType targetHolder) {
      assert constraint != Constraint.NEVER;
      assert constraint != Constraint.ALWAYS;
      assert targetHolder != null;
      this.constraint = constraint;
      this.targetHolder = targetHolder;
    }

    public boolean isAlways() {
      return constraint.isAlways();
    }

    public boolean isNever() {
      return constraint.isNever();
    }

    @Override
    public int hashCode() {
      if (targetHolder == null) {
        return constraint.ordinal();
      }
      return constraint.ordinal() * targetHolder.computeHashCode();
    }

    @Override
    @SuppressWarnings("ReferenceEquality")
    public boolean equals(Object other) {
      if (!(other instanceof ConstraintWithTarget)) {
        return false;
      }
      ConstraintWithTarget o = (ConstraintWithTarget) other;
      return this.constraint.ordinal() == o.constraint.ordinal()
          && this.targetHolder == o.targetHolder;
    }

    @SuppressWarnings("ReferenceEquality")
    public static ConstraintWithTarget deriveConstraint(
        ProgramMethod context, DexType targetHolder, AccessFlags<?> flags, AppView<?> appView) {
      if (flags.isPublic()) {
        return ALWAYS;
      } else if (flags.isPrivate()) {
        if (context.getHolder().isInANest()) {
          return NestUtils.sameNest(context.getHolderType(), targetHolder, appView)
              ? new ConstraintWithTarget(Constraint.SAMENEST, targetHolder)
              : NEVER;
        }
        return targetHolder == context.getHolderType()
            ? new ConstraintWithTarget(Constraint.SAMECLASS, targetHolder)
            : NEVER;
      } else if (flags.isProtected()) {
        if (targetHolder.isSamePackage(context.getHolderType())) {
          // Even though protected, this is visible via the same package from the context.
          return new ConstraintWithTarget(Constraint.PACKAGE, targetHolder);
        } else if (appView.isSubtype(context.getHolderType(), targetHolder).isTrue()) {
          return new ConstraintWithTarget(Constraint.SUBCLASS, targetHolder);
        }
        return NEVER;
      } else {
        /* package-private */
        return targetHolder.isSamePackage(context.getHolderType())
            ? new ConstraintWithTarget(Constraint.PACKAGE, targetHolder)
            : NEVER;
      }
    }

    public static ConstraintWithTarget classIsVisible(
        ProgramMethod context, DexType clazz, AppView<?> appView) {
      if (clazz.isArrayType()) {
        return classIsVisible(context, clazz.toArrayElementType(appView.dexItemFactory()), appView);
      }

      if (clazz.isPrimitiveType()) {
        return ALWAYS;
      }

      DexClass definition = appView.definitionFor(clazz);
      return definition == null
          ? NEVER
          : deriveConstraint(context, clazz, definition.accessFlags, appView);
    }

    @SuppressWarnings("ReferenceEquality")
    public static ConstraintWithTarget meet(
        ConstraintWithTarget one, ConstraintWithTarget other, AppView<?> appView) {
      if (one.equals(other)) {
        return one;
      }
      if (other.constraint.ordinal() < one.constraint.ordinal()) {
        return meet(other, one, appView);
      }
      // From now on, one.constraint.ordinal() <= other.constraint.ordinal()
      if (one.isNever()) {
        return NEVER;
      }
      if (other == ALWAYS) {
        return one;
      }
      int constraint = one.constraint.value | other.constraint.value;
      assert !Constraint.NEVER.isSet(constraint);
      assert !Constraint.ALWAYS.isSet(constraint);
      // SAMECLASS <= SAMECLASS, SAMENEST, PACKAGE, SUBCLASS
      if (Constraint.SAMECLASS.isSet(constraint)) {
        assert one.constraint == Constraint.SAMECLASS;
        if (other.constraint == Constraint.SAMECLASS) {
          assert one.targetHolder != other.targetHolder;
          return NEVER;
        }
        if (other.constraint == Constraint.SAMENEST) {
          if (NestUtils.sameNest(one.targetHolder, other.targetHolder, appView)) {
            return one;
          }
          return NEVER;
        }
        if (other.constraint == Constraint.PACKAGE) {
          if (one.targetHolder.isSamePackage(other.targetHolder)) {
            return one;
          }
          return NEVER;
        }
        assert other.constraint == Constraint.SUBCLASS;
        if (appView.isSubtype(one.targetHolder, other.targetHolder).isTrue()) {
          return one;
        }
        return NEVER;
      }
      // SAMENEST <= SAMENEST, PACKAGE, SUBCLASS
      if (Constraint.SAMENEST.isSet(constraint)) {
        assert one.constraint == Constraint.SAMENEST;
        if (other.constraint == Constraint.SAMENEST) {
          if (NestUtils.sameNest(one.targetHolder, other.targetHolder, appView)) {
            return one;
          }
          return NEVER;
        }
        assert verifyAllNestInSamePackage(one.targetHolder, appView);
        if (other.constraint == Constraint.PACKAGE) {
          if (one.targetHolder.isSamePackage(other.targetHolder)) {
            return one;
          }
          return NEVER;
        }
        assert other.constraint == Constraint.SUBCLASS;
        if (allNestMembersSubtypeOf(one.targetHolder, other.targetHolder, appView)) {
          // Then, SAMENEST is a more restrictive constraint.
          return one;
        }
        return NEVER;
      }
      // PACKAGE <= PACKAGE, SUBCLASS
      if (Constraint.PACKAGE.isSet(constraint)) {
        assert one.constraint == Constraint.PACKAGE;
        if (other.constraint == Constraint.PACKAGE) {
          assert one.targetHolder != other.targetHolder;
          if (one.targetHolder.isSamePackage(other.targetHolder)) {
            return one;
          }
          // PACKAGE of x and PACKAGE of y cannot be satisfied together.
          return NEVER;
        }
        assert other.constraint == Constraint.SUBCLASS;
        if (other.targetHolder.isSamePackage(one.targetHolder)) {
          // Then, PACKAGE is more restrictive constraint.
          return one;
        }
        if (appView.isSubtype(one.targetHolder, other.targetHolder).isTrue()) {
          return new ConstraintWithTarget(Constraint.SAMECLASS, one.targetHolder);
        }
        // TODO(b/128967328): towards finer-grained constraints, we need both.
        // The target method is still inlineable to methods with a holder from the same package of
        // one's holder and a subtype of other's holder.
        return NEVER;
      }
      // SUBCLASS <= SUBCLASS
      assert Constraint.SUBCLASS.isSet(constraint);
      assert one.constraint == other.constraint;
      assert one.targetHolder != other.targetHolder;
      if (appView.isSubtype(one.targetHolder, other.targetHolder).isTrue()) {
        return one;
      }
      if (appView.isSubtype(other.targetHolder, one.targetHolder).isTrue()) {
        return other;
      }
      // SUBCLASS of x and SUBCLASS of y while x and y are not a subtype of each other.
      return NEVER;
    }

    private static boolean allNestMembersSubtypeOf(
        DexType nestType, DexType superType, AppView<?> appView) {
      DexClass dexClass = appView.definitionFor(nestType);
      if (dexClass == null) {
        assert false;
        return false;
      }
      if (!dexClass.isInANest()) {
        return appView.isSubtype(dexClass.type, superType).isTrue();
      }
      DexClass nestHost =
          dexClass.isNestHost() ? dexClass : appView.definitionFor(dexClass.getNestHost());
      if (nestHost == null) {
        assert false;
        return false;
      }
      for (NestMemberClassAttribute member : nestHost.getNestMembersClassAttributes()) {
        if (!appView.isSubtype(member.getNestMember(), superType).isTrue()) {
          return false;
        }
      }
      return true;
    }

    private static boolean verifyAllNestInSamePackage(DexType type, AppView<?> appView) {
      String descr = type.getPackageDescriptor();
      DexClass dexClass = appView.definitionFor(type);
      assert dexClass != null;
      if (!dexClass.isInANest()) {
        return true;
      }
      DexClass nestHost =
          dexClass.isNestHost() ? dexClass : appView.definitionFor(dexClass.getNestHost());
      assert nestHost != null;
      for (NestMemberClassAttribute member : nestHost.getNestMembersClassAttributes()) {
        assert member.getNestMember().getPackageDescriptor().equals(descr);
      }
      return true;
    }
  }

  /**
   * Encodes the reason why a method should be inlined.
   * <p>
   * This is independent of determining whether a method can be inlined, except for the FORCE state,
   * that will inline a method irrespective of visibility and instruction checks.
   */
  public enum Reason {
    ALWAYS,        // Inlinee is marked for inlining due to alwaysinline directive.
    SINGLE_CALLER, // Inlinee has precisely one caller.
    // Inlinee has multiple callers and should not be inlined. Only used during the primary
    // optimization pass.
    MULTI_CALLER_CANDIDATE,
    SIMPLE,        // Inlinee has simple code suitable for inlining.
    NEVER;         // Inlinee must not be inlined.
  }

  public abstract static class InlineResult {

    InlineAction asInlineAction() {
      return null;
    }

    boolean isRetryAction() {
      return false;
    }
  }

  public static class InlineAction extends InlineResult {

    public final ProgramMethod target;
    public final Invoke invoke;
    final Reason reason;

    private boolean shouldEnsureStaticInitialization;

    private DexProgramClass downcastClass;

    InlineAction(ProgramMethod target, Invoke invoke, Reason reason) {
      this.target = target;
      this.invoke = invoke;
      this.reason = reason;
    }

    public static Builder builder() {
      return new Builder();
    }

    @Override
    InlineAction asInlineAction() {
      return this;
    }

    DexProgramClass getDowncastClass() {
      return downcastClass;
    }

    void setDowncastClass(DexProgramClass downcastClass) {
      this.downcastClass = downcastClass;
    }

    void setShouldEnsureStaticInitialization() {
      shouldEnsureStaticInitialization = true;
    }

    boolean mustBeInlined() {
      return reason == Reason.ALWAYS;
    }

    IRCode buildInliningIR(
        AppView<AppInfoWithLiveness> appView,
        InvokeMethod invoke,
        ProgramMethod context,
        InliningIRProvider inliningIRProvider) {
      DexItemFactory dexItemFactory = appView.dexItemFactory();
      InternalOptions options = appView.options();

      // Build the IR for a yet not processed method, and perform minimal IR processing.
      IRCode code = inliningIRProvider.getInliningIR(invoke, target);

      // Insert a init class instruction if this is needed to preserve class initialization
      // semantics.
      if (shouldEnsureStaticInitialization) {
        handleSimpleEffectAnalysisResult(
            SimpleDominatingEffectAnalysis.triggersClassInitializationBeforeAnyStaticRead(
                appView, code, context),
            code.entryBlock(),
            ConsumerUtils.emptyConsumer(),
            failingBlock -> synthesizeInitClass(code, failingBlock));
      }

      // Insert a null check if this is needed to preserve the implicit null check for the receiver.
      // This is only needed if we do not also insert a monitor-enter instruction, since that will
      // throw a NPE if the receiver is null.
      //
      // Note: When generating DEX, we synthesize monitor-enter/exit instructions during IR
      // building, and therefore, we do not need to do anything here. Upon writing, we will use the
      // flag "declared synchronized" instead of "synchronized".
      boolean shouldSynthesizeMonitorEnterExit =
          target.getDefinition().isSynchronized() && options.isGeneratingClassFiles();
      boolean isSynthesizingNullCheckForReceiverUsingMonitorEnter =
          shouldSynthesizeMonitorEnterExit && !target.getDefinition().isStatic();
      if (invoke.isInvokeMethodWithReceiver()
          && invoke.asInvokeMethodWithReceiver().getReceiver().isMaybeNull()
          && !isSynthesizingNullCheckForReceiverUsingMonitorEnter) {
        handleSimpleEffectAnalysisResult(
            canInlineWithoutSynthesizingNullCheckForReceiver(appView, code),
            code.entryBlock(),
            this::setRemoveInnerFramePositionForReceiverUse,
            failingBlock -> synthesizeNullCheckForReceiver(appView, code, invoke, failingBlock));
      }
      // Insert monitor-enter and monitor-exit instructions if the method is synchronized.
      if (shouldSynthesizeMonitorEnterExit) {
        TypeElement throwableType =
            TypeElement.fromDexType(
                dexItemFactory.throwableType, Nullability.definitelyNotNull(), appView);

        code.prepareBlocksForCatchHandlers();

        // Create a block for holding the monitor-exit instruction.
        BasicBlock monitorExitBlock = new BasicBlock();
        monitorExitBlock.setNumber(code.getNextBlockNumber());

        // For each block in the code that may throw, add a catch-all handler targeting the
        // monitor-exit block.
        List<BasicBlock> moveExceptionBlocks = new ArrayList<>();
        for (BasicBlock block : code.blocks) {
          if (!block.canThrow()) {
            continue;
          }
          if (block.hasCatchHandlers()
              && block.getCatchHandlersWithSuccessorIndexes().hasCatchAll(dexItemFactory)) {
            continue;
          }
          BasicBlock moveExceptionBlock =
              BasicBlock.createGotoBlock(
                  code.getNextBlockNumber(), Position.none(), code.metadata(), monitorExitBlock);
          InstructionListIterator moveExceptionBlockIterator =
              moveExceptionBlock.listIterator(code);
          moveExceptionBlockIterator.setInsertionPosition(Position.syntheticNone());
          moveExceptionBlockIterator.add(
              new MoveException(
                  code.createValue(throwableType), dexItemFactory.throwableType, options));
          block.appendCatchHandler(moveExceptionBlock, dexItemFactory.throwableType);
          moveExceptionBlocks.add(moveExceptionBlock);
        }

        InstructionListIterator monitorExitBlockIterator = null;
        if (!moveExceptionBlocks.isEmpty()) {
          // Create a phi for the exception values such that we can rethrow the exception if needed.
          Value exceptionValue;
          if (moveExceptionBlocks.size() == 1) {
            exceptionValue =
                ListUtils.first(moveExceptionBlocks).getInstructions().getFirst().outValue();
          } else {
            Phi phi = code.createPhi(monitorExitBlock, throwableType);
            List<Value> operands =
                ListUtils.map(
                    moveExceptionBlocks, block -> block.getInstructions().getFirst().outValue());
            phi.addOperands(operands);
            exceptionValue = phi;
          }

          monitorExitBlockIterator = monitorExitBlock.listIterator(code);
          monitorExitBlockIterator.setInsertionPosition(Position.syntheticNone());
          monitorExitBlockIterator.add(new Throw(exceptionValue));
          monitorExitBlock.getMutablePredecessors().addAll(moveExceptionBlocks);

          // Insert the newly created blocks.
          code.blocks.addAll(moveExceptionBlocks);
          code.blocks.add(monitorExitBlock);
        }

        // Create a block for holding the monitor-enter instruction. Note that, since this block
        // is created after we attach catch-all handlers to the code, this block will not have any
        // catch handlers.
        BasicBlock entryBlock = code.entryBlock();
        InstructionListIterator entryBlockIterator = entryBlock.listIterator(code);
        entryBlockIterator.nextUntil(not(Instruction::isArgument));
        entryBlockIterator.previous();
        BasicBlock monitorEnterBlock = entryBlockIterator.split(code, 0, null);
        assert !monitorEnterBlock.hasCatchHandlers();

        InstructionListIterator monitorEnterBlockIterator = monitorEnterBlock.listIterator(code);
        // MonitorEnter will only throw an NPE if the lock is null and that can only happen if the
        // receiver was null. To preserve NPE's at call-sites for synchronized methods we therefore
        // put in the invoke-position.
        monitorEnterBlockIterator.setInsertionPosition(invoke.getPosition());

        // If this is a static method, then the class object will act as the lock, so we load it
        // using a const-class instruction.
        Value lockValue;
        if (target.getDefinition().isStatic()) {
          lockValue = code.createValue(TypeElement.classClassType(appView, definitelyNotNull()));
          monitorEnterBlockIterator.add(new ConstClass(lockValue, target.getHolderType()));
        } else {
          lockValue = entryBlock.getInstructions().getFirst().asArgument().outValue();
        }

        // Insert the monitor-enter and monitor-exit instructions.
        monitorEnterBlockIterator.add(new Monitor(MonitorType.ENTER, lockValue));
        if (monitorExitBlockIterator != null) {
          monitorExitBlockIterator.previous();
          monitorExitBlockIterator.add(new Monitor(MonitorType.EXIT, lockValue));
          monitorExitBlock.close(null);
        }

        for (BasicBlock block : code.blocks) {
          if (block.exit().isReturn()) {
            // Since return instructions are not allowed after a throwing instruction in a block
            // with catch handlers, the call to prepareBlocksForCatchHandlers() has already taken
            // care of ensuring that all return blocks have no throwing instructions.
            assert !block.canThrow();

            InstructionListIterator instructionIterator =
                block.listIterator(code, block.getInstructions().size() - 1);
            instructionIterator.setInsertionPosition(Position.syntheticNone());
            instructionIterator.add(new Monitor(MonitorType.EXIT, lockValue));
          }
        }
      }
      if (options.testing.inlineeIrModifier != null) {
        options.testing.inlineeIrModifier.accept(code);
      }
      code.removeRedundantBlocks();
      assert code.isConsistentSSA(appView);
      return code;
    }

    private void handleSimpleEffectAnalysisResult(
        SimpleEffectAnalysisResult result,
        BasicBlock entryBlock,
        Consumer<Instruction> satisfyingInstructionConsumer,
        Consumer<BasicBlock> failingPathConsumer) {
      List<BasicBlock> topmostNotSatisfiedBlocks = result.getTopmostNotSatisfiedBlocks();
      if (result.isNotSatisfied()
          // We should only handle partial results if the number of failing paths are small (1) and
          // if the failing blocks that root the failing paths do not have catch handlers.
          || (result.isPartial() && topmostNotSatisfiedBlocks.size() > 1)
          || (result.isPartial() && topmostNotSatisfiedBlocks.get(0).hasCatchHandlers())) {
        failingPathConsumer.accept(entryBlock);
      } else {
        result.forEachSatisfyingInstruction(satisfyingInstructionConsumer);
        topmostNotSatisfiedBlocks.forEach(failingPathConsumer);
      }
    }

    private void synthesizeInitClass(IRCode code, BasicBlock block) {
      // Insert a new block between the last argument instruction and the first actual instruction
      // of the method, or the first instruction if not entry block.
      assert !block.hasCatchHandlers();
      BasicBlock initClassBlock =
          block
              .listIterator(code, block.isEntry() ? code.collectArguments().size() : 0)
              .split(code, 0, null);
      assert !initClassBlock.hasCatchHandlers();

      InstructionListIterator iterator = initClassBlock.listIterator(code);
      iterator.setInsertionPosition(invoke.getPosition());
      iterator.add(new InitClass(code.createValue(TypeElement.getInt()), target.getHolderType()));
    }

    private void synthesizeNullCheckForReceiver(
        AppView<?> appView, IRCode code, InvokeMethod invoke, BasicBlock block) {
      List<Value> arguments = code.collectArguments();
      if (!arguments.isEmpty()) {
        Value receiver = arguments.get(0);
        assert receiver.isThis();
        // Insert a new block between the last argument instruction and the first actual
        // instruction of the method.
        BasicBlock throwBlock =
            block.listIterator(code, block.isEntry() ? arguments.size() : 0).split(code, 0, null);
        assert !throwBlock.hasCatchHandlers();

        InstructionListIterator iterator = throwBlock.listIterator(code);
        iterator.setInsertionPosition(invoke.getPosition());
        DexMethod getClassMethod = appView.dexItemFactory().objectMembers.getClass;
        iterator.add(new InvokeVirtual(getClassMethod, null, ImmutableList.of(receiver)));
      } else {
        assert false : "Unable to synthesize a null check for the receiver";
      }
    }

    private void setRemoveInnerFramePositionForReceiverUse(Instruction instruction) {
      Position position = instruction.getPosition();
      if (position == null) {
        assert false : "Expected position for inlinee call to receiver";
        return;
      }
      Position outermostCaller = position.getOutermostCaller();
      Position removeInnerFrame =
          outermostCaller.builderWithCopy().setRemoveInnerFramesIfThrowingNpe(true).build();
      instruction.forceOverwritePosition(
          position.replacePosition(outermostCaller, removeInnerFrame));
    }

    public static class Builder {

      private DexProgramClass downcastClass;
      private InvokeMethod invoke;
      private Reason reason;
      private boolean shouldEnsureStaticInitialization;
      private ProgramMethod target;

      Builder setDowncastClass(DexProgramClass downcastClass) {
        this.downcastClass = downcastClass;
        return this;
      }

      Builder setInvoke(InvokeMethod invoke) {
        this.invoke = invoke;
        return this;
      }

      Builder setReason(Reason reason) {
        this.reason = reason;
        return this;
      }

      Builder setShouldEnsureStaticInitialization() {
        this.shouldEnsureStaticInitialization = true;
        return this;
      }

      Builder setTarget(ProgramMethod target) {
        this.target = target;
        return this;
      }

      InlineAction build() {
        InlineAction action = new InlineAction(target, invoke, reason);
        if (downcastClass != null) {
          action.setDowncastClass(downcastClass);
        }
        if (shouldEnsureStaticInitialization) {
          action.setShouldEnsureStaticInitialization();
        }
        return action;
      }
    }
  }

  public static class RetryAction extends InlineResult {

    @Override
    boolean isRetryAction() {
      return true;
    }
  }

  static int numberOfInstructions(IRCode code) {
    int numberOfInstructions = 0;
    for (BasicBlock block : code.blocks) {
      for (Instruction instruction : block.getInstructions()) {
        assert !instruction.isDebugInstruction();

        // Do not include argument instructions since they do not materialize in the output.
        if (instruction.isArgument()) {
          continue;
        }

        // Do not include assume instructions in the calculation of the inlining budget, since they
        // do not materialize in the output.
        if (instruction.isAssume()) {
          continue;
        }

        // Do not include goto instructions that target a basic block with exactly one predecessor,
        // since these goto instructions will generally not materialize.
        if (instruction.isGoto()) {
          if (instruction.asGoto().getTarget().getPredecessors().size() == 1) {
            continue;
          }
        }

        // Do not include return instructions since they do not materialize once inlined.
        if (instruction.isReturn()) {
          continue;
        }

        ++numberOfInstructions;
      }
    }
    return numberOfInstructions;
  }

  public static class InliningInfo {
    public final ProgramMethod target;
    public final DexProgramClass receiverClass; // null, if unknown

    public InliningInfo(ProgramMethod target) {
      this(target, null);
    }

    public InliningInfo(ProgramMethod target, DexProgramClass receiverClass) {
      this.target = target;
      this.receiverClass = receiverClass;
    }
  }

  public void performForcedInlining(
      ProgramMethod method,
      IRCode code,
      Map<? extends InvokeMethod, InliningInfo> invokesToInline,
      OptimizationFeedback feedback,
      InliningIRProvider inliningIRProvider,
      MethodProcessor methodProcessor,
      Timing timing) {
    ForcedInliningOracle oracle = new ForcedInliningOracle(appView, invokesToInline);
    performInliningImpl(
        oracle, method, code, feedback, inliningIRProvider, methodProcessor, timing);
  }

  public void performInlining(
      ProgramMethod method,
      IRCode code,
      OptimizationFeedback feedback,
      MethodProcessor methodProcessor,
      Timing timing) {
    performInlining(
        method,
        code,
        feedback,
        methodProcessor,
        timing,
        createDefaultInliningReasonStrategy(methodProcessor));
  }

  public void performInlining(
      ProgramMethod method,
      IRCode code,
      OptimizationFeedback feedback,
      MethodProcessor methodProcessor,
      Timing timing,
      InliningReasonStrategy inliningReasonStrategy) {
    InlinerOptions options = appView.options().inlinerOptions();
    DefaultInliningOracle oracle =
        createDefaultOracle(
            method,
            methodProcessor,
            options.inliningInstructionAllowance - numberOfInstructions(code),
            inliningReasonStrategy);
    InliningIRProvider inliningIRProvider =
        new InliningIRProvider(appView, method, code, lensCodeRewriter, methodProcessor);
    assert inliningIRProvider.verifyIRCacheIsEmpty();
    performInliningImpl(
        oracle, method, code, feedback, inliningIRProvider, methodProcessor, timing);
  }

  public InliningReasonStrategy createDefaultInliningReasonStrategy(
      MethodProcessor methodProcessor) {
    DefaultInliningReasonStrategy defaultInliningReasonStrategy =
        new DefaultInliningReasonStrategy(appView, methodProcessor.getCallSiteInformation());
    return appView.withGeneratedMessageLiteShrinker(
        ignore -> new ProtoInliningReasonStrategy(appView, defaultInliningReasonStrategy),
        defaultInliningReasonStrategy);
  }

  public DefaultInliningOracle createDefaultOracle(
      ProgramMethod method,
      MethodProcessor methodProcessor,
      int inliningInstructionAllowance) {
    return createDefaultOracle(
        method,
        methodProcessor,
        inliningInstructionAllowance,
        createDefaultInliningReasonStrategy(methodProcessor));
  }

  public DefaultInliningOracle createDefaultOracle(
      ProgramMethod method,
      MethodProcessor methodProcessor,
      int inliningInstructionAllowance,
      InliningReasonStrategy inliningReasonStrategy) {
    return new DefaultInliningOracle(
        appView,
        inliningReasonStrategy,
        method,
        methodProcessor,
        inliningInstructionAllowance);
  }

  private void performInliningImpl(
      InliningOracle oracle,
      ProgramMethod context,
      IRCode code,
      OptimizationFeedback feedback,
      InliningIRProvider inliningIRProvider,
      MethodProcessor methodProcessor,
      Timing timing) {
    AffectedValues affectedValues = new AffectedValues();
    Set<BasicBlock> blocksToRemove = Sets.newIdentityHashSet();
    BasicBlockIterator blockIterator = code.listIterator();
    ClassInitializationAnalysis classInitializationAnalysis =
        new ClassInitializationAnalysis(appView, code);
    Deque<BasicBlock> inlineeStack = new ArrayDeque<>();
    InlinerOptions options = appView.options().inlinerOptions();
    while (blockIterator.hasNext()) {
      BasicBlock block = blockIterator.next();
      if (!inlineeStack.isEmpty() && inlineeStack.peekFirst() == block) {
        inlineeStack.pop();
      }
      if (blocksToRemove.contains(block)) {
        continue;
      }
      InstructionListIterator iterator = block.listIterator(code);
      while (iterator.hasNext()) {
        Instruction current = iterator.next();
        if (current.isInvokeMethod()) {
          InvokeMethod invoke = current.asInvokeMethod();
          // TODO(b/142116551): This should be equivalent to invoke.lookupSingleTarget()!
          DexMethod invokedMethod = invoke.getInvokedMethod();
          SingleResolutionResult<?> resolutionResult =
              appView
                  .appInfo()
                  .resolveMethodLegacy(invokedMethod, invoke.getInterfaceBit())
                  .asSingleResolution();
          if (resolutionResult == null
              || resolutionResult.isAccessibleFrom(context, appView).isPossiblyFalse()) {
            continue;
          }

          if (tryInlineMethodWithoutSideEffects(
              code, iterator, invoke, resolutionResult.getResolutionPair())) {
            continue;
          }

          // TODO(b/156853206): Should not duplicate resolution.
          ProgramMethod singleTarget = oracle.lookupSingleTarget(invoke, context);
          if (singleTarget == null) {
            WhyAreYouNotInliningReporter.handleInvokeWithUnknownTarget(
                this, invoke, appView, context);
            continue;
          }

          InliningOracle singleTargetOracle = getSingleTargetOracle(invoke, singleTarget, oracle);
          DexEncodedMethod singleTargetMethod = singleTarget.getDefinition();
          WhyAreYouNotInliningReporter whyAreYouNotInliningReporter =
              singleTargetOracle.isForcedInliningOracle()
                  ? NopWhyAreYouNotInliningReporter.getInstance()
                  : createWhyAreYouNotInliningReporter(singleTarget, context);
          InlineResult inlineResult =
              singleTargetOracle.computeInlining(
                  code,
                  invoke,
                  resolutionResult,
                  singleTarget,
                  context,
                  classInitializationAnalysis,
                  inliningIRProvider,
                  whyAreYouNotInliningReporter);
          if (inlineResult == null) {
            assert whyAreYouNotInliningReporter.unsetReasonHasBeenReportedFlag();
            continue;
          }

          if (inlineResult.isRetryAction()) {
            enqueueMethodForReprocessing(context);
            continue;
          }

          InlineAction action = inlineResult.asInlineAction();
          if (action.reason == Reason.MULTI_CALLER_CANDIDATE) {
            assert methodProcessor.isPrimaryMethodProcessor();
            continue;
          }

          if (!singleTargetOracle.stillHasBudget(action, whyAreYouNotInliningReporter)) {
            assert whyAreYouNotInliningReporter.unsetReasonHasBeenReportedFlag();
            continue;
          }

          IRCode inlinee = action.buildInliningIR(appView, invoke, context, inliningIRProvider);
          if (singleTargetOracle.willExceedBudget(
              action, code, inlinee, invoke, block, whyAreYouNotInliningReporter)) {
            assert whyAreYouNotInliningReporter.unsetReasonHasBeenReportedFlag();
            continue;
          }

          // Verify this code went through the full pipeline.
          assert singleTarget.getDefinition().isProcessed();

          boolean inlineeMayHaveInvokeMethod = inlinee.metadata().mayHaveInvokeMethod();

          // Inline the inlinee code in place of the invoke instruction
          // Back up before the invoke instruction.
          iterator.previous();

          // Intentionally not using singleTargetOracle here, so that we decrease the inlining
          // instruction allowance on the default inlining oracle when force inlining methods.
          oracle.markInlined(inlinee);

          iterator.inlineInvoke(
              appView, code, inlinee, blockIterator, blocksToRemove, action.getDowncastClass());

          if (methodProcessor.getCallSiteInformation().hasSingleCallSite(singleTarget, context)) {
            feedback.markInlinedIntoSingleCallSite(singleTargetMethod);
            if (!(methodProcessor instanceof OneTimeMethodProcessor)) {
              assert converter.isInWave();
              if (singleCallerInlinedMethodsInWave.isEmpty()) {
                converter.addWaveDoneAction(this::onWaveDone);
              }
              singleCallerInlinedMethodsInWave
                  .computeIfAbsent(
                      singleTarget.getHolder(), ignoreKey(ProgramMethodMap::createConcurrent))
                  .put(singleTarget, context);
            }
          }

          classInitializationAnalysis.notifyCodeHasChanged();
          postProcessInlineeBlocks(
              code, blockIterator, block, affectedValues, blocksToRemove, timing);

          // The synthetic and bridge flags are maintained only if the inlinee has also these flags.
          if (context.getAccessFlags().isBridge() && !singleTarget.getAccessFlags().isBridge()) {
            context.getAccessFlags().demoteFromBridge();
          }
          if (context.getAccessFlags().isSynthetic()
              && !singleTarget.getAccessFlags().isSynthetic()) {
            context.getAccessFlags().demoteFromSynthetic();
          }

          context.getDefinition().copyMetadata(appView, singleTargetMethod);

          if (inlineeMayHaveInvokeMethod) {
            int inliningDepth = inlineeStack.size() + 1;
            if (options.shouldApplyInliningToInlinee(appView, singleTarget, inliningDepth)) {
              // Record that we will be inside the inlinee until the next block.
              BasicBlock inlineeEnd = IteratorUtils.peekNext(blockIterator);
              inlineeStack.push(inlineeEnd);
              // Move the cursor back to where the first inlinee block was added.
              IteratorUtils.previousUntil(blockIterator, previous -> previous == block);
              blockIterator.next();
            }
          }
        }
      }
    }
    assert inlineeStack.isEmpty();
    code.removeBlocks(blocksToRemove);
    classInitializationAnalysis.finish();
    code.removeAllDeadAndTrivialPhis(affectedValues);
    affectedValues.narrowingWithAssumeRemoval(appView, code);
    code.removeRedundantBlocks();
    assert code.isConsistentSSA(appView);
  }

  private InliningOracle getSingleTargetOracle(
      InvokeMethod invoke, ProgramMethod singleTarget, InliningOracle oracle) {
    return oracle.isForcedInliningOracle() || !singleTarget.getOptimizationInfo().forceInline()
        ? oracle
        : new ForcedInliningOracle(
            appView, ImmutableMap.of(invoke, new InliningInfo(singleTarget)));
  }

  private boolean tryInlineMethodWithoutSideEffects(
      IRCode code,
      InstructionListIterator iterator,
      InvokeMethod invoke,
      DexClassAndMethod resolvedMethod) {
    if (invoke.isInvokeMethodWithReceiver()) {
      if (!iterator.replaceCurrentInstructionByNullCheckIfPossible(appView, code.context())) {
        return false;
      }
    } else if (invoke.isInvokeStatic()) {
      if (!iterator.removeOrReplaceCurrentInstructionByInitClassIfPossible(
          appView, code, resolvedMethod.getHolderType())) {
        return false;
      }
    } else {
      return false;
    }

    // Succeeded.
    return true;
  }

  private boolean containsPotentialCatchHandlerVerificationError(IRCode code) {
    if (availableApiExceptions == null) {
      assert !appView.options().canHaveDalvikCatchHandlerVerificationBug();
      return false;
    }
    for (BasicBlock block : code.blocks) {
      for (CatchHandler<BasicBlock> catchHandler : block.getCatchHandlers()) {
        DexClass clazz = appView.definitionFor(catchHandler.guard);
        if ((clazz == null || clazz.isLibraryClass())
            && availableApiExceptions.canCauseVerificationError(catchHandler.guard)) {
          return true;
        }
      }
    }
    return false;
  }

  /** Applies member rebinding to the inlinee and inserts assume instructions. */
  private void postProcessInlineeBlocks(
      IRCode code,
      BasicBlockIterator blockIterator,
      BasicBlock block,
      AffectedValues affectedValues,
      Set<BasicBlock> blocksToRemove,
      Timing timing) {
    BasicBlock state = IteratorUtils.peekNext(blockIterator);

    Set<BasicBlock> inlineeBlocks = Sets.newIdentityHashSet();

    // Run member value propagation on the inlinee blocks.
    rewindBlockIterator(
        blockIterator,
        block,
        inlineeBlock -> {
          if (!blocksToRemove.contains(inlineeBlock)) {
            inlineeBlocks.add(inlineeBlock);
          }
        });
    applyMemberValuePropagationToInlinee(code, blockIterator, affectedValues, inlineeBlocks);

    // Add non-null IRs only to the inlinee blocks.
    rewindBlockIterator(blockIterator, block);
    insertAssumeInstructions(code, blockIterator, inlineeBlocks, timing);

    // Restore the old state of the iterator.
    rewindBlockIterator(blockIterator, state);
  }

  private void insertAssumeInstructions(
      IRCode code,
      BasicBlockIterator blockIterator,
      Set<BasicBlock> inlineeBlocks,
      Timing timing) {
    boolean keepRedundantBlocks = true; // since we have a live block iterator
    new AssumeInserter(appView, keepRedundantBlocks)
        .insertAssumeInstructionsInBlocks(code, blockIterator, inlineeBlocks::contains, timing);
    assert !blockIterator.hasNext();
  }

  private void applyMemberValuePropagationToInlinee(
      IRCode code,
      BasicBlockIterator blockIterator,
      AffectedValues affectedValues,
      Set<BasicBlock> inlineeBlocks) {
    new R8MemberValuePropagation(appView)
        .run(code, blockIterator, affectedValues, inlineeBlocks::contains);
    assert !blockIterator.hasNext();
  }

  private void rewindBlockIterator(ListIterator<BasicBlock> blockIterator, BasicBlock callerBlock) {
    rewindBlockIterator(blockIterator, callerBlock, ConsumerUtils.emptyConsumer());
  }

  private void rewindBlockIterator(
      ListIterator<BasicBlock> blockIterator,
      BasicBlock callerBlock,
      Consumer<BasicBlock> consumer) {
    // Move the cursor back to where the first inlinee block was added.
    while (blockIterator.hasPrevious()) {
      BasicBlock previous = blockIterator.previous();
      if (previous == callerBlock) {
        break;
      }
      consumer.accept(previous);
    }
    assert IteratorUtils.peekNext(blockIterator) == callerBlock;
  }

  public void enqueueMethodForReprocessing(ProgramMethod method) {
    singleInlineCallers.add(method, appView.graphLens());
  }

  public void onMethodPruned(ProgramMethod method) {
    onMethodCodePruned(method);
    multiCallerInliner.onMethodPruned(method);
  }

  public void onMethodCodePruned(ProgramMethod method) {
    singleInlineCallers.remove(method.getReference(), appView.graphLens());
  }

  private void onWaveDone() {
    singleCallerInlinedMethodsInWave.forEach(
        (clazz, singleCallerInlinedMethodsForClass) -> {
          // Convert and remove virtual single caller inlined methods to abstract or throw null.
          singleCallerInlinedMethodsForClass.removeIf(
              (callee, caller) -> {
                // TODO(b/203188583): Enable pruning of methods with generic signatures. For this to
                //  work we need to pass in a seed to GenericSignatureContextBuilder.create in R8.
                if (callee.getDefinition().belongsToVirtualPool()
                    || callee.getDefinition().getGenericSignature().hasSignature()) {
                  callee.convertToAbstractOrThrowNullMethod(appView);
                  converter.onMethodCodePruned(callee);
                  return true;
                }
                return false;
              });

          // Remove direct single caller inlined methods from the application.
          if (!singleCallerInlinedMethodsForClass.isEmpty()) {
            Set<DexEncodedMethod> methodsToRemove =
                singleCallerInlinedMethodsForClass
                    .streamKeys()
                    .map(DexClassAndMember::getDefinition)
                    .collect(Collectors.toSet());
            clazz.getMethodCollection().removeMethods(methodsToRemove);
            singleCallerInlinedMethodsForClass.forEach(
                (callee, caller) -> {
                  converter.onMethodFullyInlined(callee, caller);
                  singleCallerInlinedPrunedMethodsForTesting.add(callee.getReference());
                });
          }
        });
    singleCallerInlinedMethodsInWave.clear();
  }

  public void onLastWaveDone(
      PostMethodProcessor.Builder postMethodProcessorBuilder,
      ExecutorService executorService,
      Timing timing)
      throws ExecutionException {
    postMethodProcessorBuilder
        .rewrittenWithLens(appView)
        .merge(
            singleInlineCallers
                .rewrittenWithLens(appView)
                .removeIf(
                    appView,
                    method -> method.getOptimizationInfo().hasBeenInlinedIntoSingleCallSite()));
    singleInlineCallers.clear();
    multiCallerInliner.onLastWaveDone(postMethodProcessorBuilder, executorService, timing);
  }

  public static boolean verifyAllSingleCallerMethodsHaveBeenPruned(
      AppView<AppInfoWithLiveness> appView) {
    for (DexProgramClass clazz : appView.appInfo().classesWithDeterministicOrder()) {
      clazz.forEachProgramMethodMatching(
          method -> method.getOptimizationInfo().hasBeenInlinedIntoSingleCallSite(),
          method -> {
            assert !method.getDefinition().hasCode()
                || !method.canBeConvertedToAbstractMethod(appView);
          });
    }
    return true;
  }

  public boolean verifyIsPrunedDueToSingleCallerInlining(DexMethod method) {
    assert singleCallerInlinedPrunedMethodsForTesting.contains(method);
    return true;
  }

  public static boolean verifyAllMultiCallerInlinedMethodsHaveBeenPruned(AppView<?> appView) {
    for (DexProgramClass clazz : appView.appInfo().classesWithDeterministicOrder()) {
      for (DexEncodedMethod method : clazz.methods()) {
        if (method.hasCode() && method.getOptimizationInfo().isMultiCallerMethod()) {
          // TODO(b/142300882): Ensure soundness of multi caller inlining.
          // assert false;
        }
      }
    }
    return true;
  }
}