Do not write and read KotlinInterfaceDefaultImpls

This was only used in InlineTestUtil.kt and had no effect in the condition

compiler/backend/src/org/jetbrains/kotlin/codegen/InterfaceImplBodyCodegen.kt

@@ -24,9 +24,7 @@ import org.jetbrains.kotlin.codegen.state.GenerationState
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.impl.ClassDescriptorImpl
 import org.jetbrains.kotlin.load.java.JvmAbi
-import org.jetbrains.kotlin.load.java.JvmAnnotationNames.KOTLIN_INTERFACE_DEFAULT_IMPLS
 import org.jetbrains.kotlin.load.java.descriptors.JavaMethodDescriptor
-import org.jetbrains.kotlin.load.kotlin.header.KotlinClassHeader
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils
@@ -151,10 +149,9 @@ class InterfaceImplBodyCodegen(
     override fun generateKotlinAnnotation() {
         (v as InterfaceImplClassBuilder).stopCounting()
 
-        v.newAnnotation(AsmUtil.asmDescByFqNameWithoutInnerClasses(KOTLIN_INTERFACE_DEFAULT_IMPLS), true).visitEnd()
         AsmUtil.writeKotlinSyntheticClassAnnotation(v, state)
 
-        writeSyntheticClassMetadata(v, KotlinClassHeader.SyntheticClassKind.INTERFACE_DEFAULT_IMPLS);
+        writeSyntheticClassMetadata(v);
     }
 
     override fun done() {

compiler/backend/src/org/jetbrains/kotlin/codegen/PropertyReferenceCodegen.kt

@@ -161,7 +161,7 @@ class PropertyReferenceCodegen(
     override fun generateKotlinAnnotation() {
         writeKotlinSyntheticClassAnnotation(v, state)
 
-        writeSyntheticClassMetadata(v, null)
+        writeSyntheticClassMetadata(v)
     }
 
     fun putInstanceOnStack(): StackValue =

compiler/backend/src/org/jetbrains/kotlin/codegen/SamWrapperCodegen.java

@@ -96,7 +96,7 @@ public class SamWrapperCodegen {
 
         writeKotlinSyntheticClassAnnotation(cv, state);
 
-        WriteAnnotationUtilKt.writeSyntheticClassMetadata(cv, null);
+        WriteAnnotationUtilKt.writeSyntheticClassMetadata(cv);
 
         // e.g. ASM type for Function2
         Type functionAsmType = typeMapper.mapType(functionType);

compiler/backend/src/org/jetbrains/kotlin/codegen/when/MappingClassesForWhenByEnumCodegen.java

@@ -60,7 +60,7 @@ public class MappingClassesForWhenByEnumCodegen {
 
         writeKotlinSyntheticClassAnnotation(cb, state);
 
-        WriteAnnotationUtilKt.writeSyntheticClassMetadata(cb, null);
+        WriteAnnotationUtilKt.writeSyntheticClassMetadata(cb);
 
         cb.done();
     }

compiler/backend/src/org/jetbrains/kotlin/codegen/writeAnnotationUtil.kt

@@ -31,10 +31,8 @@ fun writeKotlinMetadata(cb: ClassBuilder, kind: KotlinClassHeader.Kind, action:
     av.visitEnd()
 }
 
-fun writeSyntheticClassMetadata(cb: ClassBuilder, kind: KotlinClassHeader.SyntheticClassKind?) {
+fun writeSyntheticClassMetadata(cb: ClassBuilder) {
     writeKotlinMetadata(cb, KotlinClassHeader.Kind.SYNTHETIC_CLASS) { av ->
-        if (kind != null) {
+        // Do nothing
-            av.visit(JvmAnnotationNames.SYNTHETIC_CLASS_KIND_FIELD_NAME, kind.id)
-        }
     }
 }

compiler/testData/codegen/bytecodeListing/defaultImpls.txt

@@ -14,7 +14,6 @@ public abstract class C {
     public abstract method getBar(): int
 }
 
-@kotlin.jvm.internal.KotlinInterfaceDefaultImpls
 @kotlin.jvm.internal.KotlinSyntheticClass
 @kotlin.Metadata
 public final class D$DefaultImpls {

compiler/testData/codegen/bytecodeListing/specialBridges/contains.txt

@@ -118,7 +118,6 @@ public abstract class A8 {
     public method toArray(p0: java.lang.Object[]): java.lang.Object[]
 }
 
-@kotlin.jvm.internal.KotlinInterfaceDefaultImpls
 @kotlin.jvm.internal.KotlinSyntheticClass
 @kotlin.Metadata
 public final class I1$DefaultImpls {
@@ -137,7 +136,6 @@ public abstract class I1 {
     public abstract method toArray(p0: java.lang.Object[]): java.lang.Object[]
 }
 
-@kotlin.jvm.internal.KotlinInterfaceDefaultImpls
 @kotlin.jvm.internal.KotlinSyntheticClass
 @kotlin.Metadata
 public final class I2$DefaultImpls {

compiler/tests/org/jetbrains/kotlin/codegen/AbstractBytecodeListingTest.kt

@@ -138,7 +138,7 @@ abstract class AbstractBytecodeListingTest : CodegenTestCase() {
 
         override fun visitAnnotation(desc: String, visible: Boolean): AnnotationVisitor? {
             val name = Type.getType(desc).className
-            classAnnotations.add("@$name ")
+            classAnnotations.add("@$name")
             return super.visitAnnotation(desc, visible)
         }
 

compiler/tests/org/jetbrains/kotlin/codegen/InlineTestUtil.kt

@@ -171,7 +171,7 @@ object InlineTestUtil {
     }
 
     private fun isClassOrPackagePartKind(header: KotlinClassHeader): Boolean {
-        return (header.kind == KotlinClassHeader.Kind.CLASS && !header.isLocalClass) || header.isInterfaceDefaultImpls
+        return header.kind == KotlinClassHeader.Kind.CLASS && !header.isLocalClass
     }
 
     private fun getClassHeader(file: OutputFile): KotlinClassHeader {

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/java/JvmAnnotationNames.java

@@ -16,7 +16,6 @@
 
 package org.jetbrains.kotlin.load.java;
 
-import kotlin.collections.SetsKt;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.kotlin.name.ClassId;
 import org.jetbrains.kotlin.name.FqName;
@@ -36,7 +35,6 @@ public final class JvmAnnotationNames {
     public static final FqName KOTLIN_MULTIFILE_CLASS_PART = new FqName("kotlin.jvm.internal.KotlinMultifileClassPart");
     public static final FqName KOTLIN_SYNTHETIC_CLASS = new FqName("kotlin.jvm.internal.KotlinSyntheticClass");
     public static final FqName KOTLIN_FUNCTION = new FqName("kotlin.jvm.internal.KotlinFunction");
-    public static final FqName KOTLIN_INTERFACE_DEFAULT_IMPLS = new FqName("kotlin.jvm.internal.KotlinInterfaceDefaultImpls");
     public static final FqName KOTLIN_LOCAL_CLASS = new FqName("kotlin.jvm.internal.KotlinLocalClass");
 
     public static final String VERSION_FIELD_NAME = "version";
@@ -75,9 +73,7 @@ public final class JvmAnnotationNames {
     private static final Set<JvmClassName> NULLABILITY_ANNOTATIONS = new HashSet<JvmClassName>();
     private static final Set<JvmClassName> SPECIAL_META_ANNOTATIONS = new HashSet<JvmClassName>();
     static {
-        for (FqName fqName : Arrays.asList(
+        for (FqName fqName : Arrays.asList(METADATA, KOTLIN_CLASS, KOTLIN_SYNTHETIC_CLASS, KOTLIN_LOCAL_CLASS)) {
-                METADATA, KOTLIN_CLASS, KOTLIN_SYNTHETIC_CLASS, KOTLIN_INTERFACE_DEFAULT_IMPLS, KOTLIN_LOCAL_CLASS
-        )) {
             SPECIAL_ANNOTATIONS.add(JvmClassName.byFqNameWithoutInnerClasses(fqName));
         }
 

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/kotlin/header/KotlinClassHeader.kt

@@ -26,7 +26,6 @@ class KotlinClassHeader(
         val data: Array<String>?,
         val strings: Array<String>?,
         val multifileClassName: String?,
-        val isInterfaceDefaultImpls: Boolean,
         val isLocalClass: Boolean
 ) {
     // See kotlin.Metadata
@@ -48,8 +47,7 @@ class KotlinClassHeader(
 
     enum class SyntheticClassKind(val id: Int) {
         FUNCTION(1),
-        LOCAL_CLASS(2),
+        LOCAL_CLASS(2);
-        INTERFACE_DEFAULT_IMPLS(3);
 
         companion object {
             private val entryById = values().toMapBy(SyntheticClassKind::id)

core/descriptor.loader.java/src/org/jetbrains/kotlin/load/kotlin/header/ReadKotlinClassHeaderAnnotationVisitor.java

@@ -54,7 +54,6 @@ public class ReadKotlinClassHeaderAnnotationVisitor implements AnnotationVisitor
     private String[] strings = null;
     private KotlinClassHeader.Kind headerKind = null;
     private KotlinClassHeader.SyntheticClassKind syntheticClassKind = null;
-    private boolean isInterfaceDefaultImpls = false;
     private boolean isLocalClass = false;
 
     @Nullable
@@ -79,7 +78,6 @@ public class ReadKotlinClassHeaderAnnotationVisitor implements AnnotationVisitor
                 data,
                 strings,
                 multifileClassName,
-                isInterfaceDefaultImpls || syntheticClassKind == KotlinClassHeader.SyntheticClassKind.INTERFACE_DEFAULT_IMPLS,
                 isLocalClass || syntheticClassKind == KotlinClassHeader.SyntheticClassKind.LOCAL_CLASS
         );
     }
@@ -100,11 +98,7 @@ public class ReadKotlinClassHeaderAnnotationVisitor implements AnnotationVisitor
 
         if (IGNORE_OLD_METADATA) return null;
 
-        if (KOTLIN_INTERFACE_DEFAULT_IMPLS.equals(fqName)) {
+        if (KOTLIN_LOCAL_CLASS.equals(fqName)) {
-            isInterfaceDefaultImpls = true;
-            return null;
-        }
-        else if (KOTLIN_LOCAL_CLASS.equals(fqName)) {
             isLocalClass = true;
             return null;
         }

core/runtime.jvm/src/kotlin/Metadata.kt

@@ -61,7 +61,6 @@ internal annotation class Metadata(
          *
          * 1 Anonymous class for a lambda or a function reference
          * 2 Local class or anonymous object literal
-         * 3 Implicit nested DefaultImpls class for an interface
          *
          * A value other than this (e.g. 0) or a missing value means this is a synthetic class of some other sort.
          * This kind has no effect on the compiler because it doesn't read synthetic class metadata. It may be used in IDEs and tools.