JVM IR: Generate synthetic methods for type aliases with annotations

compiler/ir/backend.common/src/org/jetbrains/kotlin/ir/builders/declarations/declarationBuilders.kt

@@ -157,7 +157,7 @@ inline fun buildFun(builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
         buildFun()
     }
 
-inline fun IrDeclarationContainer.addFunction(builder: IrFunctionBuilder.() -> Unit): IrSimpleFunction =
+inline fun IrDeclarationContainer.addFunction(builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
     buildFun(builder).also { function ->
         declarations.add(function)
         function.parent = this@addFunction

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/DeclarationOrigins.kt

@@ -35,6 +35,8 @@ interface JvmLoweredDeclarationOrigin : IrDeclarationOrigin {
     object JVM_OVERLOADS_WRAPPER : IrDeclarationOriginImpl("JVM_OVERLOADS_WRAPPER")
     object SYNTHETIC_METHOD_FOR_PROPERTY_ANNOTATIONS :
         IrDeclarationOriginImpl("SYNTHETIC_METHOD_FOR_PROPERTY_ANNOTATIONS", isSynthetic = true)
+    object SYNTHETIC_METHOD_FOR_TYPEALIAS_ANNOTATIONS :
+        IrDeclarationOriginImpl("SYNTHETIC_METHOD_FOR_TYPEALIAS_ANNOTATIONS", isSynthetic = true)
     object GENERATED_PROPERTY_REFERENCE : IrDeclarationOriginImpl("GENERATED_PROPERTY_REFERENCE", isSynthetic = true)
     object GENERATED_SAM_IMPLEMENTATION : IrDeclarationOriginImpl("GENERATED_SAM_IMPLEMENTATION", isSynthetic = true)
     object ENUM_MAPPINGS_FOR_WHEN : IrDeclarationOriginImpl("ENUM_MAPPINGS_FOR_WHEN", isSynthetic = true)

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt

@@ -148,6 +148,7 @@ private val returnableBlocksPhase = makeIrFilePhase(
 
 @Suppress("Reformat")
 private val jvmFilePhases =
+        typeAliasAnnotationMethodsPhase then
         stripTypeAliasDeclarationsPhase then
         provisionalFunctionExpressionPhase then
         inventNamesForLocalClassesPhase then

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/TypeAliasAnnotationMethodsLowering.kt

@@ -0,0 +1,58 @@
+/*
+     * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+     * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+     */
+
+package org.jetbrains.kotlin.backend.jvm.lower
+
+import org.jetbrains.kotlin.backend.common.ClassLoweringPass
+import org.jetbrains.kotlin.backend.common.CommonBackendContext
+import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
+import org.jetbrains.kotlin.backend.jvm.JvmLoweredDeclarationOrigin
+import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
+import org.jetbrains.kotlin.ir.builders.declarations.addFunction
+import org.jetbrains.kotlin.ir.declarations.IrClass
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationContainer
+import org.jetbrains.kotlin.ir.declarations.IrTypeAlias
+import org.jetbrains.kotlin.ir.expressions.impl.IrBlockBodyImpl
+import org.jetbrains.kotlin.load.java.JvmAbi
+import org.jetbrains.kotlin.name.Name
+
+
+internal val typeAliasAnnotationMethodsPhase = makeIrFilePhase(
+    ::TypeAliasAnnotationMethodsLowering,
+    name = "TypeAliasAnnotationMethodsLowering",
+    description = "Generate method stubs for type alias annotations"
+)
+
+class TypeAliasAnnotationMethodsLowering(val context: CommonBackendContext) :
+    ClassLoweringPass {
+
+    override fun lower(irClass: IrClass) {
+        irClass.visitTypeAliases()
+    }
+
+    private val IrTypeAlias.syntheticAnnotationMethodName
+        get() = Name.identifier(JvmAbi.getSyntheticMethodNameForAnnotatedTypeAlias(name))
+
+    private fun IrDeclarationContainer.visitTypeAliases() {
+        val annotatedAliases = declarations
+            .filterIsInstance<IrTypeAlias>()
+            .filter { !it.descriptor.annotations.isEmpty() }
+
+        for (alias in annotatedAliases) {
+            addFunction {
+                name = alias.syntheticAnnotationMethodName
+                visibility = alias.visibility
+                returnType = context.irBuiltIns.unitType
+                modality = Modality.OPEN
+                origin = JvmLoweredDeclarationOrigin.SYNTHETIC_METHOD_FOR_TYPEALIAS_ANNOTATIONS
+            }.apply {
+                body = IrBlockBodyImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET)
+                annotations.addAll(alias.annotations)
+                metadata = alias.metadata
+            }
+        }
+    }
+}

compiler/testData/codegen/box/annotations/annotationsOnTypeAliases.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 
 // WITH_RUNTIME

compiler/testData/compileKotlinAgainstKotlin/annotationsOnTypeAliases.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: A.kt
 package a

compiler/testData/writeFlags/typealias/syntheticAnnotationsMethod/privateTypealias.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 @Target(AnnotationTarget.TYPEALIAS)
 annotation class Anno
 

compiler/testData/writeFlags/typealias/syntheticAnnotationsMethod/publicTypealias.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 @Target(AnnotationTarget.TYPEALIAS)
 annotation class Anno