| // 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.ir.desugar.itf; |
| |
| import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.emulateInterfaceLibraryMethod; |
| |
| import com.android.tools.r8.graph.AppView; |
| import com.android.tools.r8.graph.DexClass; |
| import com.android.tools.r8.graph.DexEncodedMethod; |
| import com.android.tools.r8.graph.DexMethod; |
| import com.android.tools.r8.graph.DexProgramClass; |
| import com.android.tools.r8.graph.DexString; |
| import com.android.tools.r8.graph.DexType; |
| import com.android.tools.r8.graph.MethodAccessFlags; |
| import com.android.tools.r8.graph.ProgramMethod; |
| import com.android.tools.r8.ir.synthetic.EmulateInterfaceSyntheticCfCodeProvider; |
| import com.android.tools.r8.synthesis.SyntheticMethodBuilder; |
| import com.android.tools.r8.synthesis.SyntheticNaming; |
| import com.android.tools.r8.utils.Pair; |
| import com.android.tools.r8.utils.StringDiagnostic; |
| import com.google.common.collect.Iterables; |
| import com.google.common.collect.Sets; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collections; |
| import java.util.IdentityHashMap; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| public final class EmulatedInterfaceProcessor implements InterfaceDesugaringProcessor { |
| |
| private final AppView<?> appView; |
| private final InterfaceMethodRewriter rewriter; |
| private final Map<DexType, DexType> emulatedInterfaces; |
| private final Map<DexType, List<DexType>> emulatedInterfacesHierarchy; |
| |
| EmulatedInterfaceProcessor(AppView<?> appView, InterfaceMethodRewriter rewriter) { |
| this.appView = appView; |
| this.rewriter = rewriter; |
| emulatedInterfaces = |
| appView.options().desugaredLibraryConfiguration.getEmulateLibraryInterface(); |
| // Avoid the computation outside L8 since it is not needed. |
| emulatedInterfacesHierarchy = |
| appView.options().isDesugaredLibraryCompilation() |
| ? processEmulatedInterfaceHierarchy() |
| : Collections.emptyMap(); |
| } |
| |
| private Map<DexType, List<DexType>> processEmulatedInterfaceHierarchy() { |
| Map<DexType, List<DexType>> emulatedInterfacesHierarchy = new IdentityHashMap<>(); |
| Set<DexType> processed = Sets.newIdentityHashSet(); |
| ArrayList<DexType> emulatedInterfacesSorted = new ArrayList<>(emulatedInterfaces.keySet()); |
| emulatedInterfacesSorted.sort(DexType::compareTo); |
| for (DexType interfaceType : emulatedInterfacesSorted) { |
| processEmulatedInterfaceHierarchy(interfaceType, processed, emulatedInterfacesHierarchy); |
| } |
| return emulatedInterfacesHierarchy; |
| } |
| |
| private void processEmulatedInterfaceHierarchy( |
| DexType interfaceType, |
| Set<DexType> processed, |
| Map<DexType, List<DexType>> emulatedInterfacesHierarchy) { |
| if (processed.contains(interfaceType)) { |
| return; |
| } |
| emulatedInterfacesHierarchy.put(interfaceType, new ArrayList<>()); |
| processed.add(interfaceType); |
| DexClass theInterface = appView.definitionFor(interfaceType); |
| if (theInterface == null) { |
| return; |
| } |
| LinkedList<DexType> workList = new LinkedList<>(Arrays.asList(theInterface.interfaces.values)); |
| while (!workList.isEmpty()) { |
| DexType next = workList.removeLast(); |
| if (emulatedInterfaces.containsKey(next)) { |
| processEmulatedInterfaceHierarchy(next, processed, emulatedInterfacesHierarchy); |
| emulatedInterfacesHierarchy.get(next).add(interfaceType); |
| DexClass nextClass = appView.definitionFor(next); |
| if (nextClass != null) { |
| workList.addAll(Arrays.asList(nextClass.interfaces.values)); |
| } |
| } |
| } |
| } |
| |
| DexProgramClass ensureEmulateInterfaceLibrary( |
| DexProgramClass emulatedInterface, InterfaceProcessingDesugaringEventConsumer eventConsumer) { |
| assert rewriter.isEmulatedInterface(emulatedInterface.type); |
| DexProgramClass emulateInterfaceClass = |
| appView |
| .getSyntheticItems() |
| .ensureFixedClass( |
| SyntheticNaming.SyntheticKind.EMULATED_INTERFACE_CLASS, |
| emulatedInterface, |
| appView, |
| builder -> |
| emulatedInterface.forEachProgramMethodMatching( |
| DexEncodedMethod::isDefaultMethod, |
| method -> |
| builder.addMethod( |
| methodBuilder -> |
| synthesizeEmulatedInterfaceMethod( |
| method, emulatedInterface, methodBuilder))), |
| ignored -> {}); |
| emulateInterfaceClass.forEachProgramMethod(eventConsumer::acceptEmulatedInterfaceMethod); |
| assert emulateInterfaceClass.getType() |
| == InterfaceMethodRewriter.getEmulateLibraryInterfaceClassType( |
| emulatedInterface.type, appView.dexItemFactory()); |
| return emulateInterfaceClass; |
| } |
| |
| private void synthesizeEmulatedInterfaceMethod( |
| ProgramMethod method, DexProgramClass theInterface, SyntheticMethodBuilder methodBuilder) { |
| assert !method.getDefinition().isStatic(); |
| DexMethod libraryMethod = |
| method |
| .getReference() |
| .withHolder(emulatedInterfaces.get(theInterface.type), appView.dexItemFactory()); |
| DexMethod companionMethod = |
| rewriter.ensureDefaultAsMethodOfProgramCompanionClassStub(method).getReference(); |
| List<Pair<DexType, DexMethod>> extraDispatchCases = |
| getDispatchCases(method, theInterface, companionMethod); |
| DexMethod emulatedMethod = emulateInterfaceLibraryMethod(method, appView.dexItemFactory()); |
| methodBuilder |
| .setName(emulatedMethod.getName()) |
| .setProto(emulatedMethod.getProto()) |
| .setAccessFlags(MethodAccessFlags.createPublicStaticSynthetic()) |
| .setCode( |
| emulatedInterfaceMethod -> |
| new EmulateInterfaceSyntheticCfCodeProvider( |
| emulatedInterfaceMethod.getHolderType(), |
| method.getHolderType(), |
| companionMethod, |
| libraryMethod, |
| extraDispatchCases, |
| appView) |
| .generateCfCode()); |
| } |
| |
| private List<Pair<DexType, DexMethod>> getDispatchCases( |
| ProgramMethod method, DexProgramClass theInterface, DexMethod companionMethod) { |
| // To properly emulate the library interface call, we need to compute the interfaces |
| // inheriting from the interface and manually implement the dispatch with instance of. |
| // The list guarantees that an interface is always after interfaces it extends, |
| // hence reverse iteration. |
| List<DexType> subInterfaces = emulatedInterfacesHierarchy.get(theInterface.type); |
| List<Pair<DexType, DexMethod>> extraDispatchCases = new ArrayList<>(); |
| // In practice, there is usually a single case (except for tests), |
| // so we do not bother to make the following loop more clever. |
| Map<DexString, Map<DexType, DexType>> retargetCoreLibMember = |
| appView.options().desugaredLibraryConfiguration.getRetargetCoreLibMember(); |
| for (DexString methodName : retargetCoreLibMember.keySet()) { |
| if (method.getName() == methodName) { |
| for (DexType inType : retargetCoreLibMember.get(methodName).keySet()) { |
| DexClass inClass = appView.definitionFor(inType); |
| if (inClass != null && implementsInterface(inClass, theInterface.type)) { |
| extraDispatchCases.add( |
| new Pair<>( |
| inType, |
| appView |
| .dexItemFactory() |
| .createMethod( |
| retargetCoreLibMember.get(methodName).get(inType), |
| appView |
| .dexItemFactory() |
| .protoWithDifferentFirstParameter(companionMethod.proto, inType), |
| method.getName()))); |
| } |
| } |
| } |
| } |
| if (subInterfaces != null) { |
| for (int i = subInterfaces.size() - 1; i >= 0; i--) { |
| DexClass subInterfaceClass = appView.definitionFor(subInterfaces.get(i)); |
| assert subInterfaceClass != null; |
| // Else computation of subInterface would have failed. |
| // if the method is implemented, extra dispatch is required. |
| DexEncodedMethod result = subInterfaceClass.lookupVirtualMethod(method.getReference()); |
| if (result != null && !result.isAbstract()) { |
| extraDispatchCases.add( |
| new Pair<>( |
| subInterfaceClass.type, |
| appView |
| .dexItemFactory() |
| .createMethod( |
| rewriter.getCompanionClassType(subInterfaceClass.type), |
| appView |
| .dexItemFactory() |
| .protoWithDifferentFirstParameter( |
| companionMethod.proto, subInterfaceClass.type), |
| companionMethod.name))); |
| } |
| } |
| } else { |
| assert extraDispatchCases.size() <= 1; |
| } |
| return extraDispatchCases; |
| } |
| |
| private boolean implementsInterface(DexClass clazz, DexType interfaceType) { |
| LinkedList<DexType> workList = new LinkedList<>(Arrays.asList(clazz.interfaces.values)); |
| while (!workList.isEmpty()) { |
| DexType next = workList.removeLast(); |
| if (interfaceType == next) { |
| return true; |
| } |
| DexClass nextClass = appView.definitionFor(next); |
| if (nextClass != null) { |
| workList.addAll(Arrays.asList(nextClass.interfaces.values)); |
| } |
| } |
| return false; |
| } |
| |
| @Override |
| public void process( |
| DexProgramClass emulatedInterface, InterfaceProcessingDesugaringEventConsumer eventConsumer) { |
| if (!appView.options().isDesugaredLibraryCompilation() |
| || !rewriter.isEmulatedInterface(emulatedInterface.type) |
| || appView.isAlreadyLibraryDesugared(emulatedInterface)) { |
| return; |
| } |
| if (needsEmulateInterfaceLibrary(emulatedInterface)) { |
| ensureEmulateInterfaceLibrary(emulatedInterface, eventConsumer); |
| } |
| } |
| |
| private boolean needsEmulateInterfaceLibrary(DexProgramClass emulatedInterface) { |
| return Iterables.any(emulatedInterface.methods(), DexEncodedMethod::isDefaultMethod); |
| } |
| |
| @Override |
| public void finalizeProcessing(InterfaceProcessingDesugaringEventConsumer eventConsumer) { |
| warnMissingEmulatedInterfaces(); |
| } |
| |
| private void warnMissingEmulatedInterfaces() { |
| for (DexType interfaceType : emulatedInterfaces.keySet()) { |
| DexClass theInterface = appView.definitionFor(interfaceType); |
| if (theInterface == null) { |
| warnMissingEmulatedInterface(interfaceType); |
| } |
| } |
| } |
| |
| private void warnMissingEmulatedInterface(DexType interfaceType) { |
| StringDiagnostic warning = |
| new StringDiagnostic( |
| "Cannot emulate interface " |
| + interfaceType.getName() |
| + " because the interface is missing."); |
| appView.options().reporter.warning(warning); |
| } |
| } |
