diff --git a/src/main/java/com/android/tools/r8/R8.java b/src/main/java/com/android/tools/r8/R8.java
index e6cc1f5..a6f1b9c 100644
--- a/src/main/java/com/android/tools/r8/R8.java
+++ b/src/main/java/com/android/tools/r8/R8.java
@@ -45,8 +45,8 @@
 import com.android.tools.r8.ir.conversion.IRConverter;
 import com.android.tools.r8.ir.desugar.BackportedMethodRewriter;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryRetargeter;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
 import com.android.tools.r8.ir.desugar.RecordRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.ir.optimize.AssertionsRewriter;
 import com.android.tools.r8.ir.optimize.MethodPoolCollection;
 import com.android.tools.r8.ir.optimize.NestReducer;
diff --git a/src/main/java/com/android/tools/r8/graph/AppInfo.java b/src/main/java/com/android/tools/r8/graph/AppInfo.java
index 5d62aae..ab55c16 100644
--- a/src/main/java/com/android/tools/r8/graph/AppInfo.java
+++ b/src/main/java/com/android/tools/r8/graph/AppInfo.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.graph;
 
 import com.android.tools.r8.graph.FieldResolutionResult.SuccessfulFieldResolutionResult;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.shaking.MainDexInfo;
diff --git a/src/main/java/com/android/tools/r8/graph/GraphLens.java b/src/main/java/com/android/tools/r8/graph/GraphLens.java
index 610208f..88c0bc7 100644
--- a/src/main/java/com/android/tools/r8/graph/GraphLens.java
+++ b/src/main/java/com/android/tools/r8/graph/GraphLens.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.errors.Unreachable;
 import com.android.tools.r8.ir.code.Invoke.Type;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
-import com.android.tools.r8.ir.desugar.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
+import com.android.tools.r8.ir.desugar.itf.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
 import com.android.tools.r8.shaking.KeepInfoCollection;
 import com.android.tools.r8.utils.Action;
 import com.android.tools.r8.utils.IterableUtils;
diff --git a/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java b/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java
index 0530046..5a9ee16 100644
--- a/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java
+++ b/src/main/java/com/android/tools/r8/ir/conversion/IRConverter.java
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.ir.conversion;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.Flavor.ExcludeDexResources;
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.Flavor.IncludeAllResources;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.Flavor.ExcludeDexResources;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.Flavor.IncludeAllResources;
 import static com.android.tools.r8.ir.desugar.lambda.D8LambdaDesugaring.rewriteEnclosingLambdaMethodAttributes;
 
 import com.android.tools.r8.contexts.CompilationContext.MethodProcessingContext;
@@ -51,8 +51,8 @@
 import com.android.tools.r8.ir.desugar.DesugaredLibraryAPIConverter;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryAPIConverter.Mode;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryRetargeter;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.Flavor;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.Flavor;
 import com.android.tools.r8.ir.desugar.lambda.LambdaDeserializationMethodRemover;
 import com.android.tools.r8.ir.desugar.nest.D8NestBasedAccessDesugaring;
 import com.android.tools.r8.ir.optimize.AssertionsRewriter;
diff --git a/src/main/java/com/android/tools/r8/ir/conversion/NeedsIRDesugarUseRegistry.java b/src/main/java/com/android/tools/r8/ir/conversion/NeedsIRDesugarUseRegistry.java
index 9877f8d..750ffb4 100644
--- a/src/main/java/com/android/tools/r8/ir/conversion/NeedsIRDesugarUseRegistry.java
+++ b/src/main/java/com/android/tools/r8/ir/conversion/NeedsIRDesugarUseRegistry.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.ir.code.Invoke.Type;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryAPIConverter;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryRetargeter;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 
 class NeedsIRDesugarUseRegistry extends UseRegistry {
 
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/ClassProcessor.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/ClassProcessor.java
similarity index 99%
rename from src/main/java/com/android/tools/r8/ir/desugar/ClassProcessor.java
rename to src/main/java/com/android/tools/r8/ir/desugar/itf/ClassProcessor.java
index 6ef420d..7bf8f2f 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/ClassProcessor.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/ClassProcessor.java
@@ -1,8 +1,8 @@
-// Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
+// 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;
+package com.android.tools.r8.ir.desugar.itf;
 
 import com.android.tools.r8.errors.CompilationError;
 import com.android.tools.r8.graph.AppInfoWithClassHierarchy;
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/DefaultMethodsHelper.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/DefaultMethodsHelper.java
similarity index 92%
rename from src/main/java/com/android/tools/r8/ir/desugar/DefaultMethodsHelper.java
rename to src/main/java/com/android/tools/r8/ir/desugar/itf/DefaultMethodsHelper.java
index 838374d..717f235 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/DefaultMethodsHelper.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/DefaultMethodsHelper.java
@@ -1,8 +1,8 @@
-// Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
+// 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;
+package com.android.tools.r8.ir.desugar.itf;
 
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.graph.DexMethod;
@@ -25,7 +25,7 @@
   // and hidden default interface methods in this interface's hierarchy.
   //
   // Note that it is assumes that these lists should never be big.
-  final static class Collection {
+  static final class Collection {
     static final Collection EMPTY =
         new Collection(Collections.emptyList(), Collections.emptyList());
 
@@ -79,7 +79,8 @@
   // Create default interface collection based on collected information.
   final Collection wrapInCollection() {
     candidates.removeAll(hidden);
-    return (candidates.isEmpty() && hidden.isEmpty()) ? Collection.EMPTY
+    return (candidates.isEmpty() && hidden.isEmpty())
+        ? Collection.EMPTY
         : new Collection(Lists.newArrayList(candidates), Lists.newArrayList(hidden));
   }
 }
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/InterfaceMethodRewriter.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java
similarity index 97%
rename from src/main/java/com/android/tools/r8/ir/desugar/InterfaceMethodRewriter.java
rename to src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java
index f6a653b..1c7b3af 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/InterfaceMethodRewriter.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriter.java
@@ -1,8 +1,8 @@
-// Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
+// 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;
+package com.android.tools.r8.ir.desugar.itf;
 
 import static com.android.tools.r8.ir.code.Invoke.Type.DIRECT;
 import static com.android.tools.r8.ir.code.Invoke.Type.STATIC;
@@ -65,8 +65,9 @@
 import com.android.tools.r8.ir.code.Value;
 import com.android.tools.r8.ir.conversion.IRConverter;
 import com.android.tools.r8.ir.conversion.MethodProcessor;
-import com.android.tools.r8.ir.desugar.DefaultMethodsHelper.Collection;
-import com.android.tools.r8.ir.desugar.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
+import com.android.tools.r8.ir.desugar.DesugaredLibraryConfiguration;
+import com.android.tools.r8.ir.desugar.itf.DefaultMethodsHelper.Collection;
+import com.android.tools.r8.ir.desugar.itf.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
 import com.android.tools.r8.ir.optimize.UtilityMethodsForCodeOptimizations;
 import com.android.tools.r8.ir.optimize.UtilityMethodsForCodeOptimizations.MethodSynthesizerConsumer;
 import com.android.tools.r8.ir.optimize.UtilityMethodsForCodeOptimizations.UtilityMethodForCodeOptimizations;
@@ -151,17 +152,11 @@
   private final Map<DexType, DefaultMethodsHelper.Collection> cache = new ConcurrentHashMap<>();
 
   private final Predicate<DexType> shouldIgnoreFromReportsPredicate;
-  /**
-   * Defines a minor variation in desugaring.
-   */
+  /** Defines a minor variation in desugaring. */
   public enum Flavor {
-    /**
-     * Process all application resources.
-     */
+    /** Process all application resources. */
     IncludeAllResources,
-    /**
-     * Process all but DEX application resources.
-     */
+    /** Process all but DEX application resources. */
     ExcludeDexResources
   }
 
@@ -1049,8 +1044,9 @@
   public static DexType getInterfaceClassType(DexType type, DexItemFactory factory) {
     assert isCompanionClassType(type);
     String descriptor = type.descriptor.toString();
-    String interfaceTypeDescriptor = descriptor.substring(0,
-        descriptor.length() - 1 - COMPANION_CLASS_NAME_SUFFIX.length()) + ";";
+    String interfaceTypeDescriptor =
+        descriptor.substring(0, descriptor.length() - 1 - COMPANION_CLASS_NAME_SUFFIX.length())
+            + ";";
     return factory.createType(interfaceTypeDescriptor);
   }
 
@@ -1082,8 +1078,9 @@
   // not define this default methods, but inherits it. We are making our best effort
   // to find an appropriate method, but still use the original one in case we fail.
   private DexMethod amendDefaultMethod(DexClass classToDesugar, DexMethod method) {
-    DexMethod singleCandidate = getOrCreateInterfaceInfo(
-        classToDesugar, classToDesugar, method.holder).getSingleCandidate(method);
+    DexMethod singleCandidate =
+        getOrCreateInterfaceInfo(classToDesugar, classToDesugar, method.holder)
+            .getSingleCandidate(method);
     return singleCandidate != null ? singleCandidate : method;
   }
 
@@ -1223,9 +1220,7 @@
    * to moved default methods implementation.
    */
   public void desugarInterfaceMethods(
-      Builder<?> builder,
-      Flavor flavour,
-      ExecutorService executorService)
+      Builder<?> builder, Flavor flavour, ExecutorService executorService)
       throws ExecutionException {
     if (appView.options().isDesugaredLibraryCompilation()) {
       generateEmulateInterfaceLibrary(builder);
@@ -1428,9 +1423,7 @@
   }
 
   final DefaultMethodsHelper.Collection getOrCreateInterfaceInfo(
-      DexClass classToDesugar,
-      DexClass implementing,
-      DexType iface) {
+      DexClass classToDesugar, DexClass implementing, DexType iface) {
     DefaultMethodsHelper.Collection collection = cache.get(iface);
     if (collection != null) {
       return collection;
@@ -1441,9 +1434,7 @@
   }
 
   private DefaultMethodsHelper.Collection createInterfaceInfo(
-      DexClass classToDesugar,
-      DexClass implementing,
-      DexType iface) {
+      DexClass classToDesugar, DexClass implementing, DexType iface) {
     DefaultMethodsHelper helper = new DefaultMethodsHelper();
     DexClass definedInterface = appView.definitionFor(iface);
     if (definedInterface == null) {
@@ -1452,8 +1443,11 @@
     }
     if (!definedInterface.isInterface()) {
       throw new CompilationError(
-          "Type " + iface.toSourceString() + " is referenced as an interface from `"
-              + implementing.toString() + "`.");
+          "Type "
+              + iface.toSourceString()
+              + " is referenced as an interface from `"
+              + implementing.toString()
+              + "`.");
     }
 
     if (isNonDesugaredLibraryClass(definedInterface)) {
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/InterfaceMethodRewriterFixup.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriterFixup.java
similarity index 92%
rename from src/main/java/com/android/tools/r8/ir/desugar/InterfaceMethodRewriterFixup.java
rename to src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriterFixup.java
index bb0de67..b3d5f1b 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/InterfaceMethodRewriterFixup.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceMethodRewriterFixup.java
@@ -1,14 +1,14 @@
-// Copyright (c) 2020, the R8 project authors. Please see the AUTHORS file
+// 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;
+package com.android.tools.r8.ir.desugar.itf;
 
 import com.android.tools.r8.graph.AppView;
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.graph.DexProgramClass;
 import com.android.tools.r8.graph.EnclosingMethodAttribute;
 import com.android.tools.r8.graph.InnerClassAttribute;
-import com.android.tools.r8.ir.desugar.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
+import com.android.tools.r8.ir.desugar.itf.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
 
 class InterfaceMethodRewriterFixup {
   private final AppView<?> appView;
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/InterfaceProcessor.java b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceProcessor.java
similarity index 98%
rename from src/main/java/com/android/tools/r8/ir/desugar/InterfaceProcessor.java
rename to src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceProcessor.java
index 0199730..4caff1a 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/InterfaceProcessor.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/itf/InterfaceProcessor.java
@@ -1,8 +1,8 @@
-// Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
+// 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;
+package com.android.tools.r8.ir.desugar.itf;
 
 import static com.android.tools.r8.utils.PredicateUtils.not;
 
@@ -77,8 +77,7 @@
   // All created companion and dispatch classes indexed by interface type.
   final Map<DexClass, DexProgramClass> syntheticClasses = new IdentityHashMap<>();
 
-  InterfaceProcessor(
-      AppView<?> appView, InterfaceMethodRewriter rewriter) {
+  InterfaceProcessor(AppView<?> appView, InterfaceMethodRewriter rewriter) {
     this.appView = appView;
     this.rewriter = rewriter;
   }
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/nest/D8NestBasedAccessDesugaring.java b/src/main/java/com/android/tools/r8/ir/desugar/nest/D8NestBasedAccessDesugaring.java
index 44a37b0..b622057 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/nest/D8NestBasedAccessDesugaring.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/nest/D8NestBasedAccessDesugaring.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.ir.desugar.nest;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.reportDependencyEdge;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.reportDependencyEdge;
 
 import com.android.tools.r8.graph.AppView;
 import com.android.tools.r8.graph.ClasspathMethod;
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/Outliner.java b/src/main/java/com/android/tools/r8/ir/optimize/Outliner.java
index 0f12d78..2f32c5c 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/Outliner.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/Outliner.java
@@ -54,7 +54,7 @@
 import com.android.tools.r8.ir.code.ValueTypeConstraint;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.ir.conversion.SourceCode;
-import com.android.tools.r8.ir.desugar.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
+import com.android.tools.r8.ir.desugar.itf.InterfaceProcessor.InterfaceProcessorNestedGraphLens;
 import com.android.tools.r8.ir.optimize.Inliner.ConstraintWithTarget;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.origin.Origin;
diff --git a/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java b/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java
index 3b2c0d5..92a507b 100644
--- a/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java
+++ b/src/main/java/com/android/tools/r8/naming/ProguardMapMinifier.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.graph.ProgramField;
 import com.android.tools.r8.graph.SubtypingInfo;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.naming.ClassNameMinifier.ClassRenaming;
 import com.android.tools.r8.naming.FieldNameMinifier.FieldRenaming;
 import com.android.tools.r8.naming.MemberNaming.FieldSignature;
diff --git a/src/main/java/com/android/tools/r8/shaking/AppInfoWithLiveness.java b/src/main/java/com/android/tools/r8/shaking/AppInfoWithLiveness.java
index 4622786..69c27c5 100644
--- a/src/main/java/com/android/tools/r8/shaking/AppInfoWithLiveness.java
+++ b/src/main/java/com/android/tools/r8/shaking/AppInfoWithLiveness.java
@@ -47,8 +47,8 @@
 import com.android.tools.r8.ir.code.Invoke.Type;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryAPIConverter;
 import com.android.tools.r8.ir.desugar.DesugaredLibraryRetargeter;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
 import com.android.tools.r8.ir.desugar.LambdaDescriptor;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.synthesis.CommittedItems;
 import com.android.tools.r8.utils.CollectionUtils;
 import com.android.tools.r8.utils.InternalOptions;
diff --git a/src/main/java/com/android/tools/r8/shaking/GraphReporter.java b/src/main/java/com/android/tools/r8/shaking/GraphReporter.java
index ac0d153..963e036 100644
--- a/src/main/java/com/android/tools/r8/shaking/GraphReporter.java
+++ b/src/main/java/com/android/tools/r8/shaking/GraphReporter.java
@@ -29,7 +29,7 @@
 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.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.references.TypeReference;
 import com.android.tools.r8.utils.DequeUtils;
diff --git a/src/main/java/com/android/tools/r8/shaking/MissingClasses.java b/src/main/java/com/android/tools/r8/shaking/MissingClasses.java
index 2cce6ff..317a4cd 100644
--- a/src/main/java/com/android/tools/r8/shaking/MissingClasses.java
+++ b/src/main/java/com/android/tools/r8/shaking/MissingClasses.java
@@ -6,7 +6,7 @@
 
 import static com.android.tools.r8.ir.desugar.DesugaredLibraryAPIConverter.DESCRIPTOR_VIVIFIED_PREFIX;
 import static com.android.tools.r8.ir.desugar.DesugaredLibraryRetargeter.getRetargetPackageAndClassPrefixDescriptor;
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.EMULATE_LIBRARY_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.EMULATE_LIBRARY_CLASS_NAME_SUFFIX;
 import static com.android.tools.r8.utils.collections.IdentityHashSetFromMap.newProgramDerivedContextSet;
 
 import com.android.tools.r8.diagnostic.MissingDefinitionsDiagnostic;
diff --git a/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java b/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
index c5ce290..dfca4e2 100644
--- a/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
+++ b/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.errors.InternalCompilerError;
 import com.android.tools.r8.errors.Unimplemented;
 import com.android.tools.r8.errors.Unreachable;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
diff --git a/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java b/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
index 7f1940e..fd7a3bd 100644
--- a/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
+++ b/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
@@ -13,7 +13,7 @@
 import static org.junit.Assume.assumeFalse;
 
 import com.android.tools.r8.ToolHelper.DexVm;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java
index e542559..210967c 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerDebugTestRunner.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.classmerging.vertical;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.not;
 import static org.hamcrest.MatcherAssert.assertThat;
diff --git a/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java b/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java
index e72cf0a..5f4be39 100644
--- a/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/debug/InterfaceMethodTest.java
@@ -7,7 +7,7 @@
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.debug.DebugTestBase.JUnit3Wrapper.Command;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java b/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java
index 9a7802f..d65470d 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarInnerClassesInInterfaces.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.concurrent.Callable;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java
index d767975..4e96f57 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/EmulatedInterfacesTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.code.Instruction;
 import com.android.tools.r8.graph.DexClass;
 import com.android.tools.r8.graph.DexEncodedMethod;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.BooleanUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
diff --git a/src/test/java/com/android/tools/r8/desugar/enclosingmethod/EnclosingMethodRewriteTest.java b/src/test/java/com/android/tools/r8/desugar/enclosingmethod/EnclosingMethodRewriteTest.java
index 3e60058..c61b1fd 100644
--- a/src/test/java/com/android/tools/r8/desugar/enclosingmethod/EnclosingMethodRewriteTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/enclosingmethod/EnclosingMethodRewriteTest.java
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.desugar.enclosingmethod;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java
index c0267f2..a86ee63 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineFromStaticInterfaceMethodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
diff --git a/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java b/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java
index 2d0d180..2875a43 100644
--- a/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java
+++ b/src/test/java/com/android/tools/r8/jasmin/AnnotationCompanionClassTest.java
@@ -7,7 +7,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertFalse;
 
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
index ad3b7eb..cae1185 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.StringUtils;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
index a969d1b..961d400 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.shaking.ifrule.interfacemethoddesugaring;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPublic;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isStatic;
diff --git a/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java b/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java
index 46924fd..fe06c06 100644
--- a/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java
+++ b/src/test/java/com/android/tools/r8/synthesis/SyntheticItemsTestUtils.java
@@ -5,7 +5,7 @@
 
 import static org.hamcrest.CoreMatchers.containsString;
 
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java
index ee96d6b..a794e67 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/ClassSubject.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.utils.codeinspector;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.COMPANION_CLASS_NAME_SUFFIX;
 
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.graph.DexProgramClass;
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java b/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
index c20ccd6..c830cf6 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/CodeInspector.java
@@ -24,7 +24,7 @@
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.ir.conversion.SwitchPayloadResolver;
-import com.android.tools.r8.ir.desugar.InterfaceMethodRewriter;
+import com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.ClassNamingForNameMapper;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
diff --git a/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java b/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
index 0eb0de1..f215cca 100644
--- a/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
+++ b/src/test/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.utils.codeinspector;
 
-import static com.android.tools.r8.ir.desugar.InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX;
+import static com.android.tools.r8.ir.desugar.itf.InterfaceMethodRewriter.DEFAULT_METHOD_PREFIX;
 
 import com.android.tools.r8.cf.code.CfInstruction;
 import com.android.tools.r8.cf.code.CfPosition;