JVM IR: introduce global serialization bindings for convenience

In the old JVM backend, JvmSerializationBindings are created per
ClassBuilder, and special care must be taken to make sure that
JVM-specific metadata ends up in the correct bindings. This is
especially relevant for declarations whose metadata is moved to other
classes away from the place where the original declaration lies, for
example properties moved from companion object to the outer class, or
synthetic methods for annotation properties in interfaces moved to
DefaultImpls, or const properties in multifile parts moved to the
facade.

In the JVM IR backend, this seems not necessary and actually it's
complicated to ensure that we use the correct ClassBuilder for bindings
(see the code simplification in ClassCodegen). Therefore, in case we
don't have an easy way to retrieve the correct ClassBuilder instance, we
now write all JVM-specific metadata to the new _global_ bindings map in
GenerationState, which is used by JvmSerializerExtension as a fallback
if the ClassBuilder's local map has no relevant key.

compiler/backend/src/org/jetbrains/kotlin/codegen/serialization/JvmSerializerExtension.kt

@@ -38,6 +38,7 @@ import org.jetbrains.org.objectweb.asm.Type
 import org.jetbrains.org.objectweb.asm.commons.Method
 
 class JvmSerializerExtension(private val bindings: JvmSerializationBindings, state: GenerationState) : SerializerExtension() {
+    private val globalBindings = state.globalSerializationBindings
     private val codegenBinding = state.bindingContext
     private val typeMapper = state.typeMapper
     override val stringTable = JvmCodegenStringTable(typeMapper)
@@ -151,10 +152,10 @@ class JvmSerializerExtension(private val bindings: JvmSerializationBindings, sta
         }
     }
 
-    override fun serializeConstructor(descriptor: ConstructorDescriptor,
-                                      proto: ProtoBuf.Constructor.Builder,
-                                      childSerializer: DescriptorSerializer) {
-        val method = bindings.get(METHOD_FOR_FUNCTION, descriptor)
+    override fun serializeConstructor(
+        descriptor: ConstructorDescriptor, proto: ProtoBuf.Constructor.Builder, childSerializer: DescriptorSerializer
+    ) {
+        val method = getBinding(METHOD_FOR_FUNCTION, descriptor)
         if (method != null) {
             val signature = SignatureSerializer().methodSignature(descriptor, method)
             if (signature != null) {
@@ -163,10 +164,10 @@ class JvmSerializerExtension(private val bindings: JvmSerializationBindings, sta
         }
     }
 
-    override fun serializeFunction(descriptor: FunctionDescriptor,
-                                   proto: ProtoBuf.Function.Builder,
-                                   childSerializer: DescriptorSerializer) {
-        val method = bindings.get(METHOD_FOR_FUNCTION, descriptor)
+    override fun serializeFunction(
+        descriptor: FunctionDescriptor, proto: ProtoBuf.Function.Builder, childSerializer: DescriptorSerializer
+    ) {
+        val method = getBinding(METHOD_FOR_FUNCTION, descriptor)
         if (method != null) {
             val signature = SignatureSerializer().methodSignature(descriptor, method)
             if (signature != null) {
@@ -176,20 +177,20 @@ class JvmSerializerExtension(private val bindings: JvmSerializationBindings, sta
     }
 
     override fun serializeProperty(
-            descriptor: PropertyDescriptor,
-            proto: ProtoBuf.Property.Builder,
-            versionRequirementTable: MutableVersionRequirementTable?,
-            childSerializer: DescriptorSerializer
+        descriptor: PropertyDescriptor,
+        proto: ProtoBuf.Property.Builder,
+        versionRequirementTable: MutableVersionRequirementTable?,
+        childSerializer: DescriptorSerializer
     ) {
         val signatureSerializer = SignatureSerializer()
 
         val getter = descriptor.getter
         val setter = descriptor.setter
-        val getterMethod = if (getter == null) null else bindings.get(METHOD_FOR_FUNCTION, getter)
-        val setterMethod = if (setter == null) null else bindings.get(METHOD_FOR_FUNCTION, setter)
+        val getterMethod = if (getter == null) null else getBinding(METHOD_FOR_FUNCTION, getter)
+        val setterMethod = if (setter == null) null else getBinding(METHOD_FOR_FUNCTION, setter)
 
-        val field = bindings.get(FIELD_FOR_PROPERTY, descriptor)
-        val syntheticMethod = bindings.get(SYNTHETIC_METHOD_FOR_PROPERTY, descriptor)
+        val field = getBinding(FIELD_FOR_PROPERTY, descriptor)
+        val syntheticMethod = getBinding(SYNTHETIC_METHOD_FOR_PROPERTY, descriptor)
 
         val signature = signatureSerializer.propertySignature(
             descriptor,
@@ -232,6 +233,9 @@ class JvmSerializerExtension(private val bindings: JvmSerializationBindings, sta
         super.serializeErrorType(type, builder)
     }
 
+    private fun <K, V> getBinding(slice: SerializationMappingSlice<K, V>, key: K): V? =
+        bindings.get(slice, key) ?: globalBindings.get(slice, key)
+
     private inner class SignatureSerializer {
         fun methodSignature(descriptor: FunctionDescriptor?, method: Method): JvmProtoBuf.JvmMethodSignature? {
             val builder = JvmProtoBuf.JvmMethodSignature.newBuilder()

compiler/backend/src/org/jetbrains/kotlin/codegen/state/GenerationState.kt

@@ -18,6 +18,7 @@ import org.jetbrains.kotlin.codegen.inline.GlobalInlineContext
 import org.jetbrains.kotlin.codegen.inline.InlineCache
 import org.jetbrains.kotlin.codegen.intrinsics.IntrinsicMethods
 import org.jetbrains.kotlin.codegen.optimization.OptimizationClassBuilderFactory
+import org.jetbrains.kotlin.codegen.serialization.JvmSerializationBindings
 import org.jetbrains.kotlin.config.*
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.ScriptDescriptor
@@ -256,6 +257,8 @@ class GenerationState private constructor(
 
     val metadataVersion = configuration.get(CommonConfigurationKeys.METADATA_VERSION) ?: JvmMetadataVersion.INSTANCE
 
+    val globalSerializationBindings = JvmSerializationBindings()
+
     init {
         this.interceptedBuilderFactory = builderFactory
             .wrapWith(

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/ClassCodegen.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.backend.jvm.codegen
 
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
-import org.jetbrains.kotlin.backend.jvm.JvmLoweredDeclarationOrigin
 import org.jetbrains.kotlin.backend.jvm.lower.constantValue
 import org.jetbrains.kotlin.codegen.*
 import org.jetbrains.kotlin.codegen.binding.CodegenBinding
@@ -24,7 +23,6 @@ import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.load.kotlin.header.KotlinClassHeader
 import org.jetbrains.kotlin.name.SpecialNames
-import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.jvm.AsmTypes
 import org.jetbrains.kotlin.resolve.jvm.annotations.JVM_SYNTHETIC_ANNOTATION_FQ_NAME
 import org.jetbrains.kotlin.resolve.jvm.annotations.TRANSIENT_ANNOTATION_FQ_NAME
@@ -103,10 +101,8 @@ open class ClassCodegen protected constructor(
         val shortName = File(fileEntry.name).name
         visitor.visitSource(shortName, null)
 
-        val companionObjectCodegen = nestedClasses.firstOrNull { it.irClass.isCompanion }
-
         for (declaration in irClass.declarations) {
-            generateDeclaration(declaration, companionObjectCodegen)
+            generateDeclaration(declaration)
         }
 
         // Generate nested classes at the end, to ensure that codegen for companion object will have the necessary JVM signatures in its
@@ -186,10 +182,10 @@ open class ClassCodegen protected constructor(
         }
     }
 
-    private fun generateDeclaration(declaration: IrDeclaration, companionObjectCodegen: ClassCodegen?) {
+    private fun generateDeclaration(declaration: IrDeclaration) {
         when (declaration) {
             is IrField ->
-                generateField(declaration, companionObjectCodegen)
+                generateField(declaration)
             is IrFunction -> {
                 generateMethod(declaration)
             }
@@ -207,7 +203,7 @@ open class ClassCodegen protected constructor(
         ClassCodegen(klass, context, this).generate()
     }
 
-    private fun generateField(field: IrField, companionObjectCodegen: ClassCodegen?) {
+    private fun generateField(field: IrField) {
         if (field.origin == IrDeclarationOrigin.FAKE_OVERRIDE) return
 
         val fieldType = typeMapper.mapType(field)
@@ -228,10 +224,7 @@ open class ClassCodegen protected constructor(
 
         val descriptor = field.metadata?.descriptor
         if (descriptor != null) {
-            val codegen = if (field.origin != IrDeclarationOrigin.DELEGATE && JvmAbi.isPropertyWithBackingFieldInOuterClass(descriptor)) {
-                companionObjectCodegen ?: error("Class with a property moved from the companion must have a companion:\n${irClass.dump()}")
-            } else this
-            codegen.visitor.serializationBindings.put(JvmSerializationBindings.FIELD_FOR_PROPERTY, descriptor, fieldType to fieldName)
+            state.globalSerializationBindings.put(JvmSerializationBindings.FIELD_FOR_PROPERTY, descriptor, fieldType to fieldName)
         }
     }
 
@@ -240,21 +233,14 @@ open class ClassCodegen protected constructor(
 
         val signature = FunctionCodegen(method, this).generate().asmMethod
 
-        val metadata = method.metadata
-        when (metadata) {
+        when (val metadata = method.metadata) {
             is MetadataSource.Property -> {
                 // We can't check for JvmLoweredDeclarationOrigin.SYNTHETIC_METHOD_FOR_PROPERTY_ANNOTATIONS because for interface methods
                 // moved to DefaultImpls, origin is changed to DEFAULT_IMPLS
                 // TODO: fix origin somehow, because otherwise $annotations methods in interfaces also don't have ACC_SYNTHETIC
                 assert(method.name.asString().endsWith(JvmAbi.ANNOTATED_PROPERTY_METHOD_NAME_SUFFIX)) { method.dump() }
 
-                val codegen = if (DescriptorUtils.isInterface(metadata.descriptor.containingDeclaration)) {
-                    assert(irClass.origin == JvmLoweredDeclarationOrigin.DEFAULT_IMPLS) { irClass.dump() }
-                    parentClassCodegen!!
-                } else {
-                    this
-                }
-                codegen.visitor.serializationBindings.put(
+                state.globalSerializationBindings.put(
                     JvmSerializationBindings.SYNTHETIC_METHOD_FOR_PROPERTY, metadata.descriptor, signature
                 )
             }