~ jvm-cli: reset ir factory if an exception was thrown

~ fix BasicWasmBoxTest.kt
~ fix build of kotlin-scripting-js-test
2026-05-10 00:21:35 +00:00 · 2019-12-26 05:27:21 +03:00 · 2019-12-26 05:26:16 +03:00 · 2019-12-26 05:25:47 +03:00 · 2019-12-26 02:48:33 +03:00 · 2019-12-26 02:45:55 +03:00
172 changed files with 2519 additions and 1884 deletions
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -214,6 +214,7 @@ extra["compilerModules"] = arrayOf(
    ":compiler:frontend.java",
    ":compiler:cli-common",
    ":compiler:ir.tree",
+    ":compiler:ir.tree.impl",
    ":compiler:ir.psi2ir",
    ":compiler:ir.backend.common",
    ":compiler:backend.jvm",
--- a/compiler/cli/build.gradle.kts
+++ b/compiler/cli/build.gradle.kts
@@ -14,6 +14,7 @@ dependencies {
    compile(project(":compiler:backend"))
    compile(project(":compiler:backend.jvm"))
    compile(project(":compiler:ir.backend.common"))
+    implementation(project(":compiler:ir.tree.impl"))
    compile(project(":compiler:light-classes"))
    compile(project(":compiler:serialization"))
    compile(project(":compiler:plugin-api"))
--- a/compiler/cli/cli-js-klib/build.gradle.kts
+++ b/compiler/cli/cli-js-klib/build.gradle.kts
@@ -8,6 +8,7 @@ jvmTarget = "1.8"
 dependencies {
    compile(project(":compiler:cli"))
    compile(project(":compiler:ir.serialization.js"))
+    implementation(project(":compiler:ir.tree.impl"))
    compile(project(":kotlin-reflect"))
    compile(intellijDep()) { includeJars("picocontainer", "trove4j", "guava", "jdom", rootProject = rootProject) }
    compile(intellijCoreDep()) { includeJars("intellij-core") }
--- a/compiler/cli/cli-js-klib/src/GenerateJsIrKlib.kt
+++ b/compiler/cli/cli-js-klib/src/GenerateJsIrKlib.kt
@@ -16,6 +16,8 @@ import org.jetbrains.kotlin.cli.common.messages.*
 import org.jetbrains.kotlin.cli.jvm.compiler.EnvironmentConfigFiles
 import org.jetbrains.kotlin.cli.jvm.compiler.KotlinCoreEnvironment
 import org.jetbrains.kotlin.config.*
+import org.jetbrains.kotlin.ir.factories.DefaultIrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.js.config.JSConfigurationKeys
 import org.jetbrains.kotlin.library.resolver.KotlinLibraryResolveResult
 import org.jetbrains.kotlin.psi.KtFile
@@ -69,7 +71,8 @@ fun buildKLib(
    sources: List<String>,
    outputPath: String,
    allDependencies: KotlinLibraryResolveResult,
-    commonSources: List<String>
+    commonSources: List<String>,
+    irDeclarationFactory: IrDeclarationFactory
 ) {
    generateKLib(
        project = environment.project,
@@ -84,7 +87,8 @@ fun buildKLib(
        allDependencies = allDependencies,
        friendDependencies = emptyList(),
        outputKlibPath = outputPath,
-        nopack = true
+        nopack = true,
+        irDeclarationFactory = irDeclarationFactory
    )
 }

@@ -131,7 +135,15 @@ fun main(args: Array<String>) {
        dependencies, messageCollectorLogger(MessageCollector.NONE)
    )

-    buildKLib(moduleName, listOfKtFilesFrom(inputFiles), outputPath, resolvedLibraries, listOfKtFilesFrom(commonSources))
+
+    buildKLib(
+        moduleName,
+        listOfKtFilesFrom(inputFiles),
+        outputPath,
+        resolvedLibraries,
+        listOfKtFilesFrom(commonSources),
+        DefaultIrDeclarationFactory.createAndRegister()
+    )
 }

 // Copied here from `K2JsIrCompiler` instead of reusing in order to avoid circular dependencies between Gradle tasks
--- a/compiler/cli/cli-js/build.gradle.kts
+++ b/compiler/cli/cli-js/build.gradle.kts
@@ -14,6 +14,7 @@ dependencies {
    compile(project(":compiler:backend"))
    compile(project(":compiler:ir.backend.common"))
    compile(project(":compiler:ir.serialization.js"))
+    implementation(project(":compiler:ir.tree.impl"))
    compile(project(":compiler:backend.js"))
    compile(project(":js:js.translator"))
    compile(project(":js:js.serializer"))
--- a/compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt
+++ b/compiler/cli/cli-js/src/org/jetbrains/kotlin/cli/js/K2JsIrCompiler.kt
@@ -1,6 +1,6 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
+ * 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.cli.js
@@ -32,6 +32,8 @@ import org.jetbrains.kotlin.incremental.components.LookupTracker
 import org.jetbrains.kotlin.incremental.js.IncrementalDataProvider
 import org.jetbrains.kotlin.incremental.js.IncrementalResultsConsumer
 import org.jetbrains.kotlin.ir.backend.js.*
+import org.jetbrains.kotlin.ir.factories.DefaultIrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.js.config.EcmaVersion
 import org.jetbrains.kotlin.js.config.JSConfigurationKeys
 import org.jetbrains.kotlin.js.config.JsConfig
@@ -40,7 +42,6 @@ import org.jetbrains.kotlin.metadata.deserialization.BinaryVersion
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.serialization.js.ModuleKind
 import org.jetbrains.kotlin.util.Logger
-import org.jetbrains.kotlin.utils.JsMetadataVersion
 import org.jetbrains.kotlin.utils.KotlinPaths
 import org.jetbrains.kotlin.utils.PathUtil
 import org.jetbrains.kotlin.utils.fileUtils.withReplacedExtensionOrNull
@@ -175,6 +176,8 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
            it.libraryFile.absolutePath in friendAbsolutePaths
        }

+        val irDeclarationFactory = DefaultIrDeclarationFactory.createAndRegister()
+
        if (arguments.irProduceKlibDir || arguments.irProduceKlibFile) {
            val outputKlibPath =
                if (arguments.irProduceKlibDir)
@@ -190,10 +193,13 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
                    allDependencies = resolvedLibraries,
                    friendDependencies = friendDependencies,
                    outputKlibPath = outputKlibPath,
-                    nopack = arguments.irProduceKlibDir
+                    nopack = arguments.irProduceKlibDir,
+                    irDeclarationFactory = irDeclarationFactory
                )
            } catch (e: JsIrCompilationError) {
                return COMPILATION_ERROR
+            } finally {
+                IrDeclarationFactory.resetDefaultIrDeclarationFactory()
            }
        }

@@ -206,6 +212,7 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
                    sourcesFiles,
                    config.configuration,
                    phaseConfig,
+                    irDeclarationFactory = irDeclarationFactory,
                    allDependencies = resolvedLibraries,
                    friendDependencies = friendDependencies,
                    mainArguments = mainCallArguments,
@@ -214,6 +221,8 @@ class K2JsIrCompiler : CLICompiler<K2JSCompilerArguments>() {
                )
            } catch (e: JsIrCompilationError) {
                return COMPILATION_ERROR
+            } finally {
+                IrDeclarationFactory.resetDefaultIrDeclarationFactory()
            }

            val jsCode = if (arguments.irDce) compiledModule.dceJsCode!! else compiledModule.jsCode!!
--- a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinToJVMBytecodeCompiler.kt
+++ b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/KotlinToJVMBytecodeCompiler.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.cli.jvm.compiler
@@ -59,6 +48,8 @@ import org.jetbrains.kotlin.fir.resolve.firProvider
 import org.jetbrains.kotlin.fir.resolve.impl.FirProviderImpl
 import org.jetbrains.kotlin.fir.resolve.transformers.FirTotalResolveTransformer
 import org.jetbrains.kotlin.idea.MainFunctionDetector
+import org.jetbrains.kotlin.ir.factories.DefaultIrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.javac.JavacWrapper
 import org.jetbrains.kotlin.load.kotlin.ModuleVisibilityManager
 import org.jetbrains.kotlin.modules.Module
@@ -338,11 +329,16 @@ object KotlinToJVMBytecodeCompiler {
                    throw e
                }
            }
+            val irDeclarationFactory = DefaultIrDeclarationFactory.createAndRegister()
+
            val (moduleFragment, symbolTable, sourceManager) =
-                Fir2IrConverter.createModuleFragment(session, firFiles, moduleConfiguration.languageVersionSettings)
+                Fir2IrConverter.createModuleFragment(session, firFiles, moduleConfiguration.languageVersionSettings, irDeclarationFactory)
            val dummyBindingContext = NoScopeRecordCliBindingTrace().bindingContext

-            val codegenFactory = JvmIrCodegenFactory(moduleConfiguration.get(CLIConfigurationKeys.PHASE_CONFIG) ?: PhaseConfig(jvmPhases))
+            val codegenFactory = JvmIrCodegenFactory(
+                moduleConfiguration.get(CLIConfigurationKeys.PHASE_CONFIG) ?: PhaseConfig(jvmPhases),
+                irDeclarationFactory
+            )
            val generationState = GenerationState.Builder(
                environment.project, ClassBuilderFactories.BINARIES,
                moduleFragment.descriptor, dummyBindingContext, ktFiles,
@@ -605,6 +601,20 @@ object KotlinToJVMBytecodeCompiler {
        result: AnalysisResult,
        sourceFiles: List<KtFile>,
        module: Module?
+    ): GenerationState {
+        try {
+            return generate0(environment, configuration, result, sourceFiles, module)
+        } finally {
+            IrDeclarationFactory.resetDefaultIrDeclarationFactory()
+        }
+    }
+
+    private fun generate0(
+        environment: KotlinCoreEnvironment,
+        configuration: CompilerConfiguration,
+        result: AnalysisResult,
+        sourceFiles: List<KtFile>,
+        module: Module?
    ): GenerationState {
        val isIR = configuration.getBoolean(JVMConfigurationKeys.IR) ||
                configuration.getBoolean(CommonConfigurationKeys.USE_FIR)
@@ -618,7 +628,8 @@ object KotlinToJVMBytecodeCompiler {
        )
            .codegenFactory(
                if (isIR) JvmIrCodegenFactory(
-                    configuration.get(CLIConfigurationKeys.PHASE_CONFIG) ?: PhaseConfig(jvmPhases)
+                    configuration.get(CLIConfigurationKeys.PHASE_CONFIG) ?: PhaseConfig(jvmPhases),
+                    DefaultIrDeclarationFactory.createAndRegister()
                ) else DefaultCodegenFactory
            )
            .withModule(module)
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrConverter.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrConverter.kt
@@ -12,8 +12,9 @@ import org.jetbrains.kotlin.fir.descriptors.FirModuleDescriptor
 import org.jetbrains.kotlin.fir.psi
 import org.jetbrains.kotlin.ir.declarations.IrFile
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
-import org.jetbrains.kotlin.ir.declarations.impl.IrModuleFragmentImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.createModuleFragment
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi2ir.PsiSourceManager
@@ -24,17 +25,19 @@ object Fir2IrConverter {
        session: FirSession,
        firFiles: List<FirFile>,
        languageVersionSettings: LanguageVersionSettings,
+        irDeclarationFactory: IrDeclarationFactory,
        fakeOverrideMode: FakeOverrideMode = FakeOverrideMode.NORMAL
    ): Fir2IrResult {
        val moduleDescriptor = FirModuleDescriptor(session)
-        val symbolTable = SymbolTable()
+        val symbolTable = SymbolTable(irDeclarationFactory)
        val constantValueGenerator = ConstantValueGenerator(moduleDescriptor, symbolTable)
        val typeTranslator = TypeTranslator(symbolTable, languageVersionSettings, moduleDescriptor.builtIns)
        constantValueGenerator.typeTranslator = typeTranslator
        typeTranslator.constantValueGenerator = constantValueGenerator
-        val builtIns = IrBuiltIns(moduleDescriptor.builtIns, typeTranslator, symbolTable)
+        val builtIns = IrBuiltIns(moduleDescriptor.builtIns, typeTranslator, irDeclarationFactory, symbolTable)
        val sourceManager = PsiSourceManager()
-        val fir2irTransformer = Fir2IrVisitor(session, moduleDescriptor, symbolTable, sourceManager, builtIns, fakeOverrideMode)
+        val fir2irTransformer =
+            Fir2IrVisitor(session, moduleDescriptor, symbolTable, irDeclarationFactory, sourceManager, builtIns, fakeOverrideMode)
        val irFiles = mutableListOf<IrFile>()
        for (firFile in firFiles) {
            val irFile = firFile.accept(fir2irTransformer, null) as IrFile
@@ -43,7 +46,7 @@ object Fir2IrConverter {
            irFiles += irFile
        }

-        val irModuleFragment = IrModuleFragmentImpl(moduleDescriptor, builtIns, irFiles)
+        val irModuleFragment = irDeclarationFactory.createModuleFragment(moduleDescriptor, builtIns, irFiles)
        generateUnboundSymbolsAsDependencies(irModuleFragment, symbolTable, builtIns)
        return Fir2IrResult(irModuleFragment, symbolTable, sourceManager)
    }
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt
@@ -24,9 +24,9 @@ import org.jetbrains.kotlin.fir.symbols.impl.FirFunctionSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirTypeParameterSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirVariableSymbol
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.*
 import org.jetbrains.kotlin.ir.descriptors.*
 import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
@@ -40,6 +40,7 @@ import org.jetbrains.kotlin.psi.psiUtil.startOffsetSkippingComments
 class Fir2IrDeclarationStorage(
    private val session: FirSession,
    private val irSymbolTable: SymbolTable,
+    private val irDeclarationFactory: IrDeclarationFactory,
    private val moduleDescriptor: FirModuleDescriptor
 ) {
    private val firSymbolProvider = session.firSymbolProvider
@@ -105,7 +106,7 @@ class Fir2IrDeclarationStorage(
        thisReceiver = irSymbolTable.declareValueParameter(
            startOffset, endOffset, thisOrigin, WrappedReceiverParameterDescriptor(), thisType
        ) { symbol ->
-            IrValueParameterImpl(
+            irDeclarationFactory.createValueParameter(
                startOffset, endOffset, thisOrigin, symbol,
                Name.special("<this>"), -1, thisType,
                varargElementType = null, isCrossinline = false, isNoinline = false
@@ -137,7 +138,7 @@ class Fir2IrDeclarationStorage(
            val modality = regularClass?.modality ?: Modality.FINAL
            return klass.convertWithOffsets { startOffset, endOffset ->
                irSymbolTable.declareClass(startOffset, endOffset, origin, descriptor, modality) { symbol ->
-                    IrClassImpl(
+                    irDeclarationFactory.createClass(
                        startOffset,
                        endOffset,
                        origin,
@@ -194,7 +195,7 @@ class Fir2IrDeclarationStorage(
        val modality = Modality.FINAL
        return anonymousObject.convertWithOffsets { startOffset, endOffset ->
            irSymbolTable.declareClass(startOffset, endOffset, origin, descriptor, modality) { symbol ->
-                IrClassImpl(
+                irDeclarationFactory.createClass(
                    startOffset, endOffset, origin, symbol,
                    Name.special("<no name provided>"), anonymousObject.classKind,
                    Visibilities.LOCAL, modality,
@@ -214,7 +215,7 @@ class Fir2IrDeclarationStorage(
            val irTypeParameter =
                convertWithOffsets { startOffset, endOffset ->
                    irSymbolTable.declareGlobalTypeParameter(startOffset, endOffset, origin, descriptor) { symbol ->
-                        IrTypeParameterImpl(
+                        irDeclarationFactory.createTypeParameter(
                            startOffset, endOffset, origin, symbol,
                            name, index,
                            isReified,
@@ -271,7 +272,7 @@ class Fir2IrDeclarationStorage(
        valueParameters += irSymbolTable.declareValueParameter(
            startOffset, endOffset, origin, WrappedValueParameterDescriptor(), type
        ) { symbol ->
-            IrValueParameterImpl(
+            irDeclarationFactory.createValueParameter(
                startOffset, endOffset, IrDeclarationOrigin.DEFINED, symbol,
                Name.special("<set-?>"), 0, type,
                varargElementType = null,
@@ -306,7 +307,7 @@ class Fir2IrDeclarationStorage(
                            startOffset, endOffset, thisOrigin,
                            receiverDescriptor, type
                        ) { symbol ->
-                            IrValueParameterImpl(
+                            irDeclarationFactory.createValueParameter(
                                startOffset, endOffset, thisOrigin, symbol,
                                Name.special("<this>"), -1, type,
                                varargElementType = null, isCrossinline = false, isNoinline = false
@@ -324,7 +325,7 @@ class Fir2IrDeclarationStorage(
                    startOffset, endOffset, thisOrigin, WrappedReceiverParameterDescriptor(),
                    thisType
                ) { symbol ->
-                    IrValueParameterImpl(
+                    irDeclarationFactory.createValueParameter(
                        startOffset, endOffset, thisOrigin, symbol,
                        Name.special("<this>"), -1, thisType,
                        varargElementType = null, isCrossinline = false, isNoinline = false
@@ -371,7 +372,7 @@ class Fir2IrDeclarationStorage(
            return function.convertWithOffsets { startOffset, endOffset ->
                enterScope(descriptor)
                val result = irSymbolTable.declareSimpleFunction(startOffset, endOffset, origin, descriptor) { symbol ->
-                    IrFunctionImpl(
+                    irDeclarationFactory.createSimpleFunction(
                        startOffset, endOffset, origin, symbol,
                        function.name, function.visibility, function.modality!!,
                        function.returnTypeRef.toIrType(session, this),
@@ -413,7 +414,7 @@ class Fir2IrDeclarationStorage(
        val origin = if (isLambda) IrDeclarationOrigin.LOCAL_FUNCTION_FOR_LAMBDA else IrDeclarationOrigin.DEFINED
        return function.convertWithOffsets { startOffset, endOffset ->
            irSymbolTable.declareSimpleFunction(startOffset, endOffset, origin, descriptor) { symbol ->
-                IrFunctionImpl(
+                irDeclarationFactory.createSimpleFunction(
                    startOffset, endOffset, origin, symbol,
                    if (isLambda) Name.special("<anonymous>") else Name.special("<no name provided>"),
                    Visibilities.LOCAL, Modality.FINAL,
@@ -450,7 +451,7 @@ class Fir2IrDeclarationStorage(
        }
        val created = constructor.convertWithOffsets { startOffset, endOffset ->
            irSymbolTable.declareConstructor(startOffset, endOffset, origin, descriptor) { symbol ->
-                IrConstructorImpl(
+                irDeclarationFactory.createConstructor(
                    startOffset, endOffset, origin, symbol,
                    constructor.name, visibility,
                    constructor.returnTypeRef.toIrType(session, this),
@@ -480,7 +481,7 @@ class Fir2IrDeclarationStorage(
            origin, descriptor
        ) { symbol ->
            val accessorReturnType = if (isSetter) unitType else propertyType
-            IrFunctionImpl(
+            irDeclarationFactory.createSimpleFunction(
                startOffset, endOffset, origin, symbol,
                Name.special("<$prefix-${correspondingProperty.name}>"),
                propertyAccessor?.visibility ?: correspondingProperty.visibility,
@@ -517,7 +518,7 @@ class Fir2IrDeclarationStorage(
                    startOffset, endOffset,
                    origin, descriptor, property.delegate != null
                ) { symbol ->
-                    IrPropertyImpl(
+                    irDeclarationFactory.createProperty(
                        startOffset, endOffset, origin, symbol,
                        property.name, property.visibility, property.modality!!,
                        isVar = property.isVar,
@@ -569,7 +570,7 @@ class Fir2IrDeclarationStorage(
                    startOffset, endOffset,
                    origin, descriptor, type
                ) { symbol ->
-                    IrFieldImpl(
+                    irDeclarationFactory.createField(
                        startOffset, endOffset, origin, symbol,
                        field.name, type, field.visibility,
                        isFinal = field.modality == Modality.FINAL,
@@ -592,7 +593,7 @@ class Fir2IrDeclarationStorage(
            irSymbolTable.declareValueParameter(
                startOffset, endOffset, origin, descriptor, type
            ) { symbol ->
-                IrValueParameterImpl(
+                irDeclarationFactory.createValueParameter(
                    startOffset, endOffset, origin, symbol,
                    valueParameter.name, index, type,
                    null, valueParameter.isCrossinline, valueParameter.isNoinline
@@ -620,7 +621,7 @@ class Fir2IrDeclarationStorage(
    ): IrVariable {
        val descriptor = WrappedVariableDescriptor()
        return irSymbolTable.declareVariable(startOffset, endOffset, origin, descriptor, type) { symbol ->
-            IrVariableImpl(
+            irDeclarationFactory.createVariable(
                startOffset, endOffset, origin, symbol, name, type,
                isVar, isConst, isLateinit
            ).apply {
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
@@ -36,13 +36,12 @@ import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.createFile
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.types.impl.IrErrorTypeImpl
@@ -61,6 +60,7 @@ class Fir2IrVisitor(
    private val session: FirSession,
    private val moduleDescriptor: FirModuleDescriptor,
    private val symbolTable: SymbolTable,
+    private val irDeclarationFactory: IrDeclarationFactory,
    private val sourceManager: PsiSourceManager,
    override val irBuiltIns: IrBuiltIns,
    private val fakeOverrideMode: FakeOverrideMode
@@ -75,7 +75,7 @@ class Fir2IrVisitor(

    private val typeContext = session.typeContext

-    private val declarationStorage = Fir2IrDeclarationStorage(session, symbolTable, moduleDescriptor)
+    private val declarationStorage = Fir2IrDeclarationStorage(session, symbolTable, irDeclarationFactory, moduleDescriptor)

    private val nothingType = session.builtinTypes.nothingType.toIrType(session, declarationStorage)

@@ -143,7 +143,7 @@ class Fir2IrVisitor(
    }

    override fun visitFile(file: FirFile, data: Any?): IrFile {
-        return IrFileImpl(
+        return irDeclarationFactory.createFile(
            sourceManager.getOrCreateFileEntry(file.psi as KtFile),
            moduleDescriptor.findPackageFragmentForFile(file)
        ).withParent {
@@ -313,7 +313,7 @@ class Fir2IrVisitor(
            startOffset, endOffset, thisOrigin, WrappedValueParameterDescriptor(),
            thisType
        ) { symbol ->
-            IrValueParameterImpl(
+            irDeclarationFactory.createValueParameter(
                startOffset, endOffset, thisOrigin, symbol,
                Name.special("<this>"), -1, thisType,
                varargElementType = null, isCrossinline = false, isNoinline = false
@@ -507,7 +507,7 @@ class Fir2IrVisitor(
        return symbolTable.declareField(
            startOffset, endOffset, origin, descriptor, inferredType
        ) { symbol ->
-            IrFieldImpl(
+            irDeclarationFactory.createField(
                startOffset, endOffset, origin, symbol,
                name, inferredType,
                visibility, isFinal = isFinal, isExternal = false,
--- a/compiler/fir/fir2ir/tests/org/jetbrains/kotlin/fir/AbstractFir2IrTextTest.kt
+++ b/compiler/fir/fir2ir/tests/org/jetbrains/kotlin/fir/AbstractFir2IrTextTest.kt
@@ -92,7 +92,7 @@ abstract class AbstractFir2IrTextTest : AbstractIrTextTestCase() {
        }

        return Fir2IrConverter.createModuleFragment(
-            session, firFiles, myEnvironment.configuration.languageVersionSettings
+            session, firFiles, myEnvironment.configuration.languageVersionSettings, irDeclarationFactory
        ).irModuleFragment
    }
 }
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/BackendContext.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/BackendContext.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.common
@@ -22,6 +11,7 @@ import org.jetbrains.kotlin.backend.common.ir.SharedVariablesManager
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.name.FqName
@@ -30,8 +20,9 @@ interface BackendContext {
    val ir: Ir<CommonBackendContext>
    val builtIns: KotlinBuiltIns
    val irBuiltIns: IrBuiltIns
+    val irDeclarationFactory: IrDeclarationFactory
    val sharedVariablesManager: SharedVariablesManager
-    val declarationFactory: DeclarationFactory
+    val declarationFactory: DeclarationFactory ///
    val internalPackageFqn: FqName
    val transformedFunction: MutableMap<IrFunctionSymbol, IrSimpleFunctionSymbol>
    val lateinitNullableFields: MutableMap<IrField, IrField>
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/DeepCopyIrTreeWithDeclarations.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/DeepCopyIrTreeWithDeclarations.kt
@@ -1,27 +1,16 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.common

 import org.jetbrains.kotlin.descriptors.VariableDescriptor
-import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrVariable
 import org.jetbrains.kotlin.ir.descriptors.WrappedVariableDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrLoop
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.util.DeepCopyIrTreeWithSymbols
 import org.jetbrains.kotlin.ir.util.DeepCopySymbolRemapper
 import org.jetbrains.kotlin.ir.util.DeepCopyTypeRemapper
@@ -29,7 +18,7 @@ import org.jetbrains.kotlin.ir.util.DescriptorsRemapper
 import org.jetbrains.kotlin.ir.visitors.acceptVoid

@Suppress("UNCHECKED_CAST")
-fun <T : IrElement> T.deepCopyWithVariables(): T {
+fun <T : IrElement> T.deepCopyWithVariables(irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT): T {
    val descriptorsRemapper = object : DescriptorsRemapper {
        override fun remapDeclaredVariable(descriptor: VariableDescriptor) = WrappedVariableDescriptor()
    }
@@ -40,7 +29,7 @@ fun <T : IrElement> T.deepCopyWithVariables(): T {
    val typesRemapper = DeepCopyTypeRemapper(symbolsRemapper)

    return this.transform(
-            object : DeepCopyIrTreeWithSymbols(symbolsRemapper, typesRemapper) {
+            object : DeepCopyIrTreeWithSymbols(irDeclarationFactory, symbolsRemapper, typesRemapper) {
                override fun getNonTransformedLoop(irLoop: IrLoop): IrLoop {
                    return irLoop
                }
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/IrElementTransformerVoidWithContext.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/IrElementTransformerVoidWithContext.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.common
@@ -26,12 +15,12 @@ import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid

 open class ScopeWithIr(val scope: Scope, val irElement: IrElement)

-abstract class IrElementTransformerVoidWithContext : IrElementTransformerVoid() {
+abstract class IrElementTransformerVoidWithContext(open protected val context: CommonBackendContext) : IrElementTransformerVoid() {

    private val scopeStack = mutableListOf<ScopeWithIr>()

    protected open fun createScope(declaration: IrSymbolOwner): ScopeWithIr =
-        ScopeWithIr(Scope(declaration.symbol), declaration)
+        ScopeWithIr(Scope(declaration.symbol, context.irDeclarationFactory), declaration)

    final override fun visitFile(declaration: IrFile): IrFile {
        scopeStack.push(createScope(declaration))
@@ -114,12 +103,12 @@ abstract class IrElementTransformerVoidWithContext : IrElementTransformerVoid()
    }
 }

-abstract class IrElementVisitorVoidWithContext : IrElementVisitorVoid {
+abstract class IrElementVisitorVoidWithContext(open protected val context: CommonBackendContext) : IrElementVisitorVoid {

    private val scopeStack = mutableListOf<ScopeWithIr>()

    protected open fun createScope(declaration: IrSymbolOwner): ScopeWithIr =
-        ScopeWithIr(Scope(declaration.symbol), declaration)
+        ScopeWithIr(Scope(declaration.symbol, context.irDeclarationFactory), declaration)

    final override fun visitFile(declaration: IrFile) {
        scopeStack.push(createScope(declaration))
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/extensions/IrGenerationExtension.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/extensions/IrGenerationExtension.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -12,6 +12,7 @@ import org.jetbrains.kotlin.extensions.ProjectExtensionDescriptor
 import org.jetbrains.kotlin.ir.builders.IrGeneratorContext
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.ir.util.TypeTranslator
 import org.jetbrains.kotlin.resolve.BindingContext
@@ -23,6 +24,7 @@ class IrPluginContext(
    val symbolTable: SymbolTable,
    val typeTranslator: TypeTranslator,
    override val irBuiltIns: IrBuiltIns,
+    val irDeclarationFactory: IrDeclarationFactory,
    val symbols: BuiltinSymbolsBase = BuiltinSymbolsBase(irBuiltIns.builtIns, symbolTable)
 ) : IrGeneratorContext()

--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt
@@ -18,13 +18,11 @@ import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.Scope
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrTypeParameterImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.createValueParameter
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrConstructorSymbolImpl
@@ -59,9 +57,10 @@ fun IrClass.addSimpleDelegatingConstructor(
    superConstructor: IrConstructor,
    irBuiltIns: IrBuiltIns,
    isPrimary: Boolean = false,
-    origin: IrDeclarationOrigin? = null
+    origin: IrDeclarationOrigin? = null,
+    irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT
 ) = WrappedClassConstructorDescriptor().let { descriptor ->
-    IrConstructorImpl(
+    irDeclarationFactory.createConstructor(
        startOffset, endOffset,
        origin ?: this.origin,
        IrConstructorSymbolImpl(descriptor),
@@ -143,7 +142,8 @@ fun IrValueParameter.copyTo(
    varargElementType: IrType? = this.varargElementType, // TODO: remapTypeParameters here as well
    defaultValue: IrExpressionBody? = this.defaultValue,
    isCrossinline: Boolean = this.isCrossinline,
-    isNoinline: Boolean = this.isNoinline
+    isNoinline: Boolean = this.isNoinline,
+    irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT
 ): IrValueParameter {
    val descriptor = if (index < 0) {
        WrappedReceiverParameterDescriptor(this.descriptor.annotations, this.descriptor.source)
@@ -153,7 +153,7 @@ fun IrValueParameter.copyTo(
    val symbol = IrValueParameterSymbolImpl(descriptor)
    val defaultValueCopy = defaultValue?.deepCopyWithVariables()
    defaultValueCopy?.patchDeclarationParents(irFunction)
-    return IrValueParameterImpl(
+    return irDeclarationFactory.createValueParameter(
        startOffset, endOffset, origin, symbol,
        name, index, type, varargElementType, isCrossinline, isNoinline
    ).also {
@@ -167,22 +167,25 @@ fun IrValueParameter.copyTo(
 fun IrTypeParameter.copyToWithoutSuperTypes(
    target: IrTypeParametersContainer,
    shift: Int = 0,
-    origin: IrDeclarationOrigin = this.origin
+    origin: IrDeclarationOrigin = this.origin,
+    irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT
 ): IrTypeParameter {
    val descriptor = WrappedTypeParameterDescriptor(symbol.descriptor.annotations, symbol.descriptor.source)
    val symbol = IrTypeParameterSymbolImpl(descriptor)
-    return IrTypeParameterImpl(startOffset, endOffset, origin, symbol, name, shift + index, isReified, variance).also { copied ->
-        descriptor.bind(copied)
-        copied.parent = target
-    }
+    return irDeclarationFactory.createTypeParameter(startOffset, endOffset, origin, symbol, name, shift + index, isReified, variance)
+        .also { copied ->
+            descriptor.bind(copied)
+            copied.parent = target
+        }
 }

-fun IrFunction.copyValueParametersFrom(from: IrFunction) {
+fun IrFunction.copyValueParametersFrom(from: IrFunction, irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT) {
    // TODO: should dispatch receiver be copied?
    dispatchReceiverParameter = from.dispatchReceiverParameter?.let {
-        IrValueParameterImpl(it.startOffset, it.endOffset, it.origin, it.descriptor, it.type, it.varargElementType).also {
-            it.parent = this
-        }
+        irDeclarationFactory.createValueParameter(it.startOffset, it.endOffset, it.origin, it.descriptor, it.type, it.varargElementType)
+            .also {
+                it.parent = this
+            }
    }
    extensionReceiverParameter = from.extensionReceiverParameter?.copyTo(this)

@@ -362,9 +365,9 @@ fun Scope.createTemporaryVariableWithWrappedDescriptor(
    ).apply { descriptor.bind(this) }
 }

-fun IrClass.createImplicitParameterDeclarationWithWrappedDescriptor() {
+fun IrClass.createImplicitParameterDeclarationWithWrappedDescriptor(irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT) {
    val thisReceiverDescriptor = WrappedReceiverParameterDescriptor()
-    thisReceiver = IrValueParameterImpl(
+    thisReceiver = irDeclarationFactory.createValueParameter(
        startOffset, endOffset,
        IrDeclarationOrigin.INSTANCE_RECEIVER,
        IrValueParameterSymbolImpl(thisReceiverDescriptor),
@@ -398,11 +401,11 @@ fun IrClass.simpleFunctions() = declarations.flatMap {
    }
 }

-fun IrClass.createParameterDeclarations() {
+fun IrClass.createParameterDeclarations(irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT) {
    assert (thisReceiver == null)

    thisReceiver = WrappedReceiverParameterDescriptor().let {
-        IrValueParameterImpl(
+        irDeclarationFactory.createValueParameter(
            startOffset, endOffset,
            IrDeclarationOrigin.INSTANCE_RECEIVER,
            IrValueParameterSymbolImpl(it),
@@ -419,10 +422,10 @@ fun IrClass.createParameterDeclarations() {
    }
 }

-fun IrFunction.createDispatchReceiverParameter(origin: IrDeclarationOrigin? = null) {
+fun IrFunction.createDispatchReceiverParameter(origin: IrDeclarationOrigin? = null, irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT) {
    assert(dispatchReceiverParameter == null)

-    dispatchReceiverParameter = IrValueParameterImpl(
+    dispatchReceiverParameter = irDeclarationFactory.createValueParameter(
        startOffset, endOffset,
        origin ?: parentAsClass.origin,
        IrValueParameterSymbolImpl(parentAsClass.thisReceiver!!.descriptor),
@@ -446,7 +449,7 @@ val IrFunction.allParameters: List<IrValueParameter>
        explicitParameters
    }

-fun IrClass.addFakeOverrides() {
+fun IrClass.addFakeOverrides(irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT) {
    fun IrDeclaration.toList() = when (this) {
        is IrSimpleFunction -> listOf(this)
        is IrProperty -> listOfNotNull(getter, setter)
@@ -474,7 +477,7 @@ fun IrClass.addFakeOverrides() {
    fun createFakeOverride(overriddenFunctions: List<IrSimpleFunction>) =
        overriddenFunctions.first().let { irFunction ->
            val descriptor = WrappedSimpleFunctionDescriptor()
-            IrFunctionImpl(
+            irDeclarationFactory.createSimpleFunction(
                UNDEFINED_OFFSET,
                UNDEFINED_OFFSET,
                IrDeclarationOrigin.FAKE_OVERRIDE,
@@ -514,12 +517,13 @@ fun createStaticFunctionWithReceivers(
    dispatchReceiverType: IrType? = oldFunction.dispatchReceiverParameter?.type,
    origin: IrDeclarationOrigin = oldFunction.origin,
    modality: Modality = Modality.FINAL,
-    copyMetadata: Boolean = true
+    copyMetadata: Boolean = true,
+    irDeclarationFactory: IrDeclarationFactory = IrDeclarationFactory.DEFAULT
 ): IrSimpleFunction {
    val descriptor = (oldFunction.descriptor as? DescriptorWithContainerSource)?.let {
        WrappedFunctionDescriptorWithContainerSource(it.containerSource)
    } ?: WrappedSimpleFunctionDescriptor(Annotations.EMPTY, oldFunction.descriptor.source)
-    return IrFunctionImpl(
+    return irDeclarationFactory.createSimpleFunction(
        oldFunction.startOffset, oldFunction.endOffset,
        origin,
        IrSimpleFunctionSymbolImpl(descriptor),
@@ -582,7 +586,7 @@ fun copyBodyWithParametersMapping(
                // Remap return targets to the static method so they do not appear to be
                // non-local returns.
                override fun visitReturn(expression: IrReturn): IrExpression {
-                    expression.transformChildrenVoid(this);
+                    expression.transformChildrenVoid(this)
                    return if (expression.returnTargetSymbol == oldFunction.symbol) {
                        IrReturnImpl(
                            expression.startOffset,
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/AbstractSuspendFunctionsLowering.kt
@@ -13,10 +13,6 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrClassImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedFieldDescriptor
@@ -281,7 +277,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
        private val unboundFunctionParameters = boundFunctionParameters?.let { functionParameters - it }

        private val coroutineClass: IrClass = WrappedClassDescriptor().let { d ->
-            IrClassImpl(
+            context.irDeclarationFactory.createClass(
                startOffset, endOffset,
                DECLARATION_ORIGIN_COROUTINE_IMPL,
                IrClassSymbolImpl(d),
@@ -385,7 +381,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
        }

        fun buildConstructor(): IrConstructor = WrappedClassConstructorDescriptor().let { d ->
-            IrConstructorImpl(
+            context.irDeclarationFactory.createConstructor(
                startOffset, endOffset,
                DECLARATION_ORIGIN_COROUTINE_IMPL,
                IrConstructorSymbolImpl(d),
@@ -431,7 +427,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
        }

        private fun buildFactoryConstructor(boundParams: List<IrValueParameter>) = WrappedClassConstructorDescriptor().let { d ->
-            IrConstructorImpl(
+            context.irDeclarationFactory.createConstructor(
                startOffset, endOffset,
                DECLARATION_ORIGIN_COROUTINE_IMPL,
                IrConstructorSymbolImpl(d),
@@ -477,7 +473,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
            superFunctionSymbol: IrSimpleFunctionSymbol?,
            coroutineConstructor: IrConstructor
        ) = WrappedSimpleFunctionDescriptor().let { d ->
-            IrFunctionImpl(
+            context.irDeclarationFactory.createSimpleFunction(
                startOffset, endOffset,
                DECLARATION_ORIGIN_COROUTINE_IMPL,
                IrSimpleFunctionSymbolImpl(d),
@@ -545,7 +541,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
            createFunction: IrFunction,
            stateMachineFunction: IrFunction
        ) = WrappedSimpleFunctionDescriptor().let { d ->
-            IrFunctionImpl(
+            context.irDeclarationFactory.createSimpleFunction(
                startOffset, endOffset,
                DECLARATION_ORIGIN_COROUTINE_IMPL,
                IrSimpleFunctionSymbolImpl(d),
@@ -605,7 +601,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
            coroutineClass: IrClass
        ): IrSimpleFunction {
            val function = WrappedSimpleFunctionDescriptor().let { d ->
-                IrFunctionImpl(
+                context.irDeclarationFactory.createSimpleFunction(
                    startOffset, endOffset,
                    DECLARATION_ORIGIN_COROUTINE_IMPL,
                    IrSimpleFunctionSymbolImpl(d),
@@ -676,7 +672,7 @@ abstract class AbstractSuspendFunctionsLowering<C : CommonBackendContext>(val co
    fun IrClass.addField(name: Name, type: IrType, isMutable: Boolean): IrField {
        val descriptor = WrappedFieldDescriptor()
        val symbol = IrFieldSymbolImpl(descriptor)
-        return IrFieldImpl(
+        return context.irDeclarationFactory.createField(
            startOffset,
            endOffset,
            DECLARATION_ORIGIN_COROUTINE_IMPL,
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/ArrayConstructorLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/ArrayConstructorLowering.kt
@@ -1,6 +1,6 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
+ * 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.common.lower
@@ -27,7 +27,7 @@ import org.jetbrains.kotlin.ir.util.patchDeclarationParents
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.util.OperatorNameConventions

-class ArrayConstructorLowering(val context: CommonBackendContext) : IrElementTransformerVoidWithContext(), FileLoweringPass {
+class ArrayConstructorLowering(context: CommonBackendContext) : IrElementTransformerVoidWithContext(context), FileLoweringPass {
    override fun lower(irFile: IrFile) {
        irFile.transformChildrenVoid(this)
    }
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/DefaultArgumentStubGenerator.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/DefaultArgumentStubGenerator.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.backend.common.descriptors.synthesizedString
 import org.jetbrains.kotlin.backend.common.ir.*
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibilities
-import org.jetbrains.kotlin.descriptors.Visibility
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/EnumWhenLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/EnumWhenLowering.kt
@@ -28,7 +28,7 @@ import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 * Replace branches that are comparisons with compile-time known enum entries
 * with comparisons of ordinals.
 */
-open class EnumWhenLowering(protected val context: CommonBackendContext) : IrElementTransformerVoidWithContext(), FileLoweringPass {
+open class EnumWhenLowering(context: CommonBackendContext) : IrElementTransformerVoidWithContext(context), FileLoweringPass {
    private val subjectWithOrdinalStack = mutableListOf<Pair<IrVariable, Lazy<IrVariable>>>()

    protected open fun mapConstEnumEntry(entry: IrEnumEntry): Int =
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/FinallyBlocksLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/FinallyBlocksLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -10,8 +10,9 @@ import org.jetbrains.kotlin.backend.common.ir.returnType
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.builders.*
-import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrVariableImpl
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
+import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedVariableDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
@@ -25,7 +26,9 @@ import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.name.Name

-class FinallyBlocksLowering(val context: CommonBackendContext, private val throwableType: IrType): FileLoweringPass, IrElementTransformerVoidWithContext() {
+class FinallyBlocksLowering(
+    context: CommonBackendContext, private val throwableType: IrType
+): FileLoweringPass, IrElementTransformerVoidWithContext(context) {

    private interface HighLevelJump {
        fun toIr(context: CommonBackendContext, startOffset: Int, endOffset: Int, value: IrExpression): IrExpression
@@ -211,7 +214,7 @@ class FinallyBlocksLowering(val context: CommonBackendContext, private val throw
        irBuilder.run {
            val transformedFinallyExpression = finallyExpression.transform(transformer, null)
            val parameter = WrappedVariableDescriptor()
-            val catchParameter = IrVariableImpl(
+            val catchParameter = this@FinallyBlocksLowering.context.irDeclarationFactory.createVariable(
                startOffset, endOffset, IrDeclarationOrigin.CATCH_PARAMETER, IrVariableSymbolImpl(parameter),
                Name.identifier("t"), throwableType, isVar = false, isConst = false, isLateinit = false
            ).also { parameter.bind(it) }
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InitializersLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InitializersLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -26,7 +26,7 @@ open class InitializersLowering(context: CommonBackendContext) : InitializersLow
        val instanceInitializerStatements = extractInitializers(irClass) {
            (it is IrField && !it.isStatic) || (it is IrAnonymousInitializer && !it.isStatic)
        }
-        irClass.transformChildrenVoid(object : IrElementTransformerVoidWithContext() {
+        irClass.transformChildrenVoid(object : IrElementTransformerVoidWithContext(context) {
            // Only transform constructors of current class.
            override fun visitClassNew(declaration: IrClass) = declaration

--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InnerClassesLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InnerClassesLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -24,7 +24,7 @@ import org.jetbrains.kotlin.ir.util.transformDeclarationsFlat
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid

-class InnerClassesLowering(val context: BackendContext) : ClassLoweringPass {
+class InnerClassesLowering(val context: CommonBackendContext) : ClassLoweringPass {
    private val IrValueSymbol.classForImplicitThis: IrClass?
        // TODO: is this the correct way to get the class?
        get() =
@@ -69,7 +69,7 @@ class InnerClassesLowering(val context: BackendContext) : ClassLoweringPass {
        irClass.transformDeclarationsFlat { irMember -> (irMember as? IrConstructor)?.let { listOf(lowerConstructor(it)) } }
        irClass.transformChildrenVoid(VariableRemapper(oldConstructorParameterToNew))

-        irClass.transformChildrenVoid(object : IrElementTransformerVoidWithContext() {
+        irClass.transformChildrenVoid(object : IrElementTransformerVoidWithContext(context) {
            override fun visitClassNew(declaration: IrClass): IrStatement =
                declaration

--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LateinitLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LateinitLowering.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.common.lower
@@ -23,7 +12,6 @@ import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.buildField
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrVariableImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedVariableDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
@@ -79,7 +67,7 @@ class LateinitLowering(val backendContext: CommonBackendContext) : FileLoweringP

                val descriptor = WrappedVariableDescriptor()
                val type = declaration.type.makeNullable()
-                val newVar = IrVariableImpl(
+                val newVar = backendContext.irDeclarationFactory.createVariable(
                    declaration.startOffset,
                    declaration.endOffset,
                    declaration.origin,
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalClassPopupLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalClassPopupLowering.kt
@@ -5,7 +5,7 @@

 package org.jetbrains.kotlin.backend.common.lower

-import org.jetbrains.kotlin.backend.common.BackendContext
+import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
 import org.jetbrains.kotlin.backend.common.IrElementTransformerVoidWithContext
 import org.jetbrains.kotlin.backend.common.ScopeWithIr
@@ -18,11 +18,11 @@ import org.jetbrains.kotlin.ir.declarations.IrScript
 import org.jetbrains.kotlin.ir.expressions.impl.IrCompositeImpl

 //This lower takes part of old LocalDeclarationLowering job to pop up local classes from functions
-open class LocalClassPopupLowering(val context: BackendContext) : FileLoweringPass {
+open class LocalClassPopupLowering(val context: CommonBackendContext) : FileLoweringPass {
    override fun lower(irFile: IrFile) {
        val extractedLocalClasses = arrayListOf<Pair<IrClass, IrDeclarationContainer>>()

-        irFile.transform(object : IrElementTransformerVoidWithContext() {
+        irFile.transform(object : IrElementTransformerVoidWithContext(context) {

            override fun visitClassNew(declaration: IrClass): IrStatement {
                val newDeclaration = super.visitClassNew(declaration)
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalDeclarationsLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalDeclarationsLowering.kt
@@ -5,7 +5,7 @@

 package org.jetbrains.kotlin.backend.common.lower

-import org.jetbrains.kotlin.backend.common.BackendContext
+import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
 import org.jetbrains.kotlin.backend.common.IrElementVisitorVoidWithContext
 import org.jetbrains.kotlin.backend.common.ScopeWithIr
@@ -20,10 +20,6 @@ import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.Scope
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedFieldDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
@@ -78,7 +74,7 @@ object BOUND_VALUE_PARAMETER : IrDeclarationOriginImpl("BOUND_VALUE_PARAMETER")
 object BOUND_RECEIVER_PARAMETER : IrDeclarationOriginImpl("BOUND_RECEIVER_PARAMETER")

 class LocalDeclarationsLowering(
-    val context: BackendContext,
+    val context: CommonBackendContext,
    val localNameProvider: LocalNameProvider = LocalNameProvider.DEFAULT,
    val visibilityPolicy: VisibilityPolicy = VisibilityPolicy.DEFAULT
 ) :
@@ -517,7 +513,7 @@ class LocalDeclarationsLowering(
            // TODO: consider using fields to access the closure of enclosing class.
            val capturedValues = localFunctionContext.closure.capturedValues

-            val newDeclaration = IrFunctionImpl(
+            val newDeclaration = context.irDeclarationFactory.createSimpleFunction(
                oldDeclaration.startOffset,
                oldDeclaration.endOffset,
                oldDeclaration.origin,
@@ -565,7 +561,7 @@ class LocalDeclarationsLowering(
            capturedValues.mapIndexedTo(this) { i, capturedValue ->
                val parameterDescriptor = WrappedValueParameterDescriptor()
                val p = capturedValue.owner
-                IrValueParameterImpl(
+                context.irDeclarationFactory.createValueParameter(
                    p.startOffset,
                    p.endOffset,
                    if (p.descriptor is ReceiverParameterDescriptor && newDeclaration is IrConstructor)
@@ -621,7 +617,7 @@ class LocalDeclarationsLowering(
            val loweredConstructorVisibility =
                visibilityPolicy.forConstructor(oldDeclaration, constructorContext.inInlineFunctionScope)

-            val newDeclaration = IrConstructorImpl(
+            val newDeclaration = context.irDeclarationFactory.createConstructor(
                oldDeclaration.startOffset, oldDeclaration.endOffset, oldDeclaration.origin,
                newSymbol, oldDeclaration.name, loweredConstructorVisibility, oldDeclaration.returnType,
                isInline = oldDeclaration.isInline,
@@ -663,7 +659,7 @@ class LocalDeclarationsLowering(
        ): IrField {
            val descriptor = WrappedFieldDescriptor()
            val symbol = IrFieldSymbolImpl(descriptor)
-            return IrFieldImpl(
+            return context.irDeclarationFactory.createField(
                startOffset,
                endOffset,
                if (isCrossinline) DECLARATION_ORIGIN_FIELD_FOR_CROSSINLINE_CAPTURED_VALUE else DECLARATION_ORIGIN_FIELD_FOR_CAPTURED_VALUE,
@@ -746,14 +742,14 @@ class LocalDeclarationsLowering(
                var counter: Int = 0
            }

-            irFile.acceptVoid(object : IrElementVisitorVoidWithContext() {
+            irFile.acceptVoid(object : IrElementVisitorVoidWithContext(context) {

                override fun visitElement(element: IrElement) {
                    element.acceptChildrenVoid(this)
                }

                override fun createScope(declaration: IrSymbolOwner): ScopeWithIr {
-                    return ScopeWithCounter(Scope(declaration.symbol), declaration)
+                    return ScopeWithCounter(Scope(declaration.symbol, context.irDeclarationFactory), declaration)
                }

                override fun visitSimpleFunction(declaration: IrSimpleFunction) {
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LowerUtils.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LowerUtils.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.common.lower
@@ -27,6 +16,7 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.types.IrSimpleType
 import org.jetbrains.kotlin.ir.types.IrType
@@ -44,7 +34,7 @@ class DeclarationIrBuilder(
    startOffset: Int = UNDEFINED_OFFSET, endOffset: Int = UNDEFINED_OFFSET
 ) : IrBuilderWithScope(
    generatorContext,
-    Scope(symbol),
+    Scope(symbol, IrDeclarationFactory.DEFAULT), ///
    startOffset,
    endOffset
 )
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/PropertiesLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/PropertiesLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.expressions.impl.IrBlockBodyImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrBlockImpl
@@ -79,10 +78,10 @@ class PropertiesLowering(
        else
            null

-    private fun createSyntheticMethodForAnnotations(declaration: IrProperty, origin: IrDeclarationOrigin, name: String): IrFunctionImpl {
+    private fun createSyntheticMethodForAnnotations(declaration: IrProperty, origin: IrDeclarationOrigin, name: String): IrFunction {
        val descriptor = WrappedSimpleFunctionDescriptor(declaration.descriptor.annotations)
        val symbol = IrSimpleFunctionSymbolImpl(descriptor)
-        return IrFunctionImpl(
+        return context.irDeclarationFactory.createSimpleFunction(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET, origin, symbol, Name.identifier(name),
            declaration.visibility, Modality.OPEN, context.irBuiltIns.unitType,
            isInline = false, isExternal = false, isTailrec = false, isSuspend = false, isExpect = false, isFakeOverride = false,
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/ReturnableBlockLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/ReturnableBlockLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -75,7 +75,7 @@ class ReturnableBlockLowering(val context: CommonBackendContext) : FileLoweringP
    }
 }

-class ReturnableBlockTransformer(val context: CommonBackendContext) : IrElementTransformerVoidWithContext() {
+class ReturnableBlockTransformer(context: CommonBackendContext) : IrElementTransformerVoidWithContext(context) {
    private var labelCnt = 0
    private val returnMap = mutableMapOf<IrReturnableBlockSymbol, (IrReturn) -> IrExpression>()

--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/inline/DeepCopyIrTreeWithDescriptors.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/inline/DeepCopyIrTreeWithDescriptors.kt
@@ -119,5 +119,10 @@ internal class DeepCopyIrTreeWithSymbolsForInliner(

    private val symbolRemapper = SymbolRemapperImpl(DescriptorsToIrRemapper)
    private val copier =
-        DeepCopyIrTreeWithSymbols(symbolRemapper, InlinerTypeRemapper(symbolRemapper, typeArguments), InlinerSymbolRenamer())
+        DeepCopyIrTreeWithSymbols(
+            context.irDeclarationFactory,
+            symbolRemapper,
+            InlinerTypeRemapper(symbolRemapper, typeArguments),
+            InlinerSymbolRenamer()
+        )
 }
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/inline/FunctionInlining.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/inline/FunctionInlining.kt
@@ -31,7 +31,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.util.OperatorNameConventions

-class FunctionInlining(val context: CommonBackendContext) : IrElementTransformerVoidWithContext() {
+class FunctionInlining(context: CommonBackendContext) : IrElementTransformerVoidWithContext(context) {

    fun inline(irModule: IrModuleFragment) = irModule.accept(this, data = null)

--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ForLoopsLowering.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ForLoopsLowering.kt
@@ -113,9 +113,9 @@ class ForLoopsLowering(val context: CommonBackendContext) : FileLoweringPass {
 }

 private class RangeLoopTransformer(
-    val context: CommonBackendContext,
+    context: CommonBackendContext,
    val oldLoopToNewLoop: MutableMap<IrLoop, IrLoop>
-) : IrElementTransformerVoidWithContext() {
+) : IrElementTransformerVoidWithContext(context) {

    private val symbols = context.ir.symbols
    private val headerInfoBuilder = DefaultHeaderInfoBuilder(context, this::getScopeOwnerSymbol)
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionHandlers.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/loops/ProgressionHandlers.kt
@@ -154,7 +154,10 @@ internal class UntilHandler(private val context: CommonBackendContext, private v
                        // Condition is needed and untilArg is non-const.
                        // Build the additional "not empty" condition: `untilArg != MIN_VALUE`.
                        // Make sure to copy untilArgExpression as it is also used in `last`.
-                        irNotEquals(untilArgExpression.deepCopyWithSymbols(), minValueIrConst)
+                        irNotEquals(
+                            untilArgExpression.deepCopyWithSymbols(irDeclarationFactory = this@UntilHandler.context.irDeclarationFactory),
+                            minValueIrConst
+                        )
                    it == minValueAsLong ->
                        // Hardcode "false" as additional condition so that the progression is considered empty.
                        // The entire lowered loop becomes a candidate for dead code elimination, depending on backend.
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/ir/builders/IrBuilders.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/ir/builders/IrBuilders.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.ir.builders
@@ -19,12 +8,14 @@ package org.jetbrains.kotlin.ir.builders
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrVariable
-import org.jetbrains.kotlin.ir.declarations.impl.IrVariableImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedVariableDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrLoop
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
-import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.expressions.impl.IrBreakImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrContinueImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrGetObjectValueImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrWhileLoopImpl
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrVariableSymbolImpl
 import org.jetbrains.kotlin.ir.types.IrType
@@ -66,7 +57,7 @@ fun Scope.createTmpVariable(
    val varType = irType ?: irExpression.type
    val descriptor = WrappedVariableDescriptor()
    val symbol = IrVariableSymbolImpl(descriptor)
-    return IrVariableImpl(
+    return irDeclarationFactory.createVariable(
        irExpression.startOffset,
        irExpression.endOffset,
        origin,
--- a/compiler/ir/backend.common/src/org/jetbrains/kotlin/ir/builders/declarations/declarationBuilders.kt
+++ b/compiler/ir/backend.common/src/org/jetbrains/kotlin/ir/builders/declarations/declarationBuilders.kt
@@ -5,12 +5,10 @@

 package org.jetbrains.kotlin.ir.builders.declarations

-import org.jetbrains.kotlin.backend.common.descriptors.*
+import org.jetbrains.kotlin.backend.common.descriptors.synthesizedName
 import org.jetbrains.kotlin.backend.common.ir.copyTo
 import org.jetbrains.kotlin.descriptors.*
-import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.*
 import org.jetbrains.kotlin.ir.descriptors.*
 import org.jetbrains.kotlin.ir.symbols.impl.*
 import org.jetbrains.kotlin.ir.types.IrType
@@ -22,7 +20,7 @@ import org.jetbrains.kotlin.types.Variance

 fun IrClassBuilder.buildClass(): IrClass {
    val wrappedDescriptor = WrappedClassDescriptor()
-    return IrClassImpl(
+    return irDeclarationFactory.createClass(
        startOffset, endOffset, origin,
        IrClassSymbolImpl(wrappedDescriptor),
        name, kind, visibility, modality,
@@ -41,7 +39,7 @@ inline fun buildClass(builder: IrClassBuilder.() -> Unit) =

 fun IrFieldBuilder.buildField(): IrField {
    val wrappedDescriptor = WrappedFieldDescriptor()
-    return IrFieldImpl(
+    return irDeclarationFactory.createField(
        startOffset, endOffset, origin,
        IrFieldSymbolImpl(wrappedDescriptor),
        name, type, visibility, isFinal, isExternal, isStatic,
@@ -72,7 +70,7 @@ fun IrClass.addField(fieldName: String, fieldType: IrType, fieldVisibility: Visi

 fun IrPropertyBuilder.buildProperty(): IrProperty {
    val wrappedDescriptor = WrappedPropertyDescriptor()
-    return IrPropertyImpl(
+    return irDeclarationFactory.createProperty(
        startOffset, endOffset, origin,
        IrPropertySymbolImpl(wrappedDescriptor),
        name, visibility, modality,
@@ -83,7 +81,7 @@ fun IrPropertyBuilder.buildProperty(): IrProperty {
    }
 }

-inline fun buildProperty(builder: IrPropertyBuilder.() -> Unit) =
+inline fun buildProperty(builder: IrPropertyBuilder.() -> Unit): IrProperty =
    IrPropertyBuilder().run {
        builder()
        buildProperty()
@@ -115,7 +113,7 @@ inline fun IrProperty.addSetter(builder: IrFunctionBuilder.() -> Unit = {}): IrS
        }
    }

-fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null): IrFunctionImpl {
+fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null): IrSimpleFunction {
    val wrappedDescriptor = when(originalDescriptor) {
        is DescriptorWithContainerSource -> WrappedFunctionDescriptorWithContainerSource(originalDescriptor.containerSource)
        is PropertyGetterDescriptor -> WrappedPropertyGetterDescriptor(originalDescriptor.annotations, originalDescriptor.source)
@@ -123,7 +121,7 @@ fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null):
        null -> WrappedSimpleFunctionDescriptor()
        else -> WrappedSimpleFunctionDescriptor(originalDescriptor)
    }
-    return IrFunctionImpl(
+    return irDeclarationFactory.createSimpleFunction(
        startOffset, endOffset, origin,
        IrSimpleFunctionSymbolImpl(wrappedDescriptor),
        name, visibility, modality, returnType,
@@ -135,9 +133,9 @@ fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null):
    }
 }

-fun IrFunctionBuilder.buildConstructor(): IrConstructorImpl {
+fun IrFunctionBuilder.buildConstructor(): IrConstructor {
    val wrappedDescriptor = WrappedClassConstructorDescriptor()
-    return IrConstructorImpl(
+    return irDeclarationFactory.createConstructor(
        startOffset, endOffset, origin,
        IrConstructorSymbolImpl(wrappedDescriptor),
        Name.special("<init>"),
@@ -153,19 +151,19 @@ fun IrFunctionBuilder.buildConstructor(): IrConstructorImpl {
 * potentially external function (e.g. in an IrCall) we have to ensure that we keep
 * information from the original descriptor so as not to break inlining.
 */
-inline fun buildFunWithDescriptorForInlining(originalDescriptor: FunctionDescriptor, builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
+inline fun buildFunWithDescriptorForInlining(originalDescriptor: FunctionDescriptor, builder: IrFunctionBuilder.() -> Unit): IrSimpleFunction =
    IrFunctionBuilder().run {
        builder()
        buildFun(originalDescriptor)
    }

-inline fun buildFun(builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
+inline fun buildFun(builder: IrFunctionBuilder.() -> Unit): IrSimpleFunction =
    IrFunctionBuilder().run {
        builder()
        buildFun()
    }

-inline fun IrDeclarationContainer.addFunction(builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
+inline fun IrDeclarationContainer.addFunction(builder: IrFunctionBuilder.() -> Unit): IrSimpleFunction =
    buildFun(builder).also { function ->
        declarations.add(function)
        function.parent = this@addFunction
@@ -191,13 +189,13 @@ fun IrDeclarationContainer.addFunction(
        }
    }

-inline fun buildConstructor(builder: IrFunctionBuilder.() -> Unit): IrConstructorImpl =
+inline fun buildConstructor(builder: IrFunctionBuilder.() -> Unit): IrConstructor =
    IrFunctionBuilder().run {
        builder()
        buildConstructor()
    }

-inline fun IrClass.addConstructor(builder: IrFunctionBuilder.() -> Unit = {}): IrConstructorImpl =
+inline fun IrClass.addConstructor(builder: IrFunctionBuilder.() -> Unit = {}): IrConstructor =
    buildConstructor {
        builder()
        returnType = defaultType
@@ -208,7 +206,7 @@ inline fun IrClass.addConstructor(builder: IrFunctionBuilder.() -> Unit = {}): I

 fun IrValueParameterBuilder.build(): IrValueParameter {
    val wrappedDescriptor = WrappedValueParameterDescriptor()
-    return IrValueParameterImpl(
+    return irDeclarationFactory.createValueParameter(
        startOffset, endOffset, origin,
        IrValueParameterSymbolImpl(wrappedDescriptor),
        name, index, type, varargElementType, isCrossInline, isNoinline
@@ -272,7 +270,7 @@ fun IrSimpleFunction.addExtensionReceiver(type: IrType, origin: IrDeclarationOri

 fun IrTypeParameterBuilder.build(): IrTypeParameter {
    val wrappedDescriptor = WrappedTypeParameterDescriptor()
-    return IrTypeParameterImpl(
+    return irDeclarationFactory.createTypeParameter(
        startOffset, endOffset, origin,
        IrTypeParameterSymbolImpl(wrappedDescriptor),
        name, index, isReified, variance
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsDeclarationFactory.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsDeclarationFactory.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -15,10 +15,9 @@ import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.backend.js.ir.JsIrBuilder
 import org.jetbrains.kotlin.ir.backend.js.utils.Namer
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedFieldDescriptor
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.impl.IrConstructorSymbolImpl
 import org.jetbrains.kotlin.ir.symbols.impl.IrFieldSymbolImpl
 import org.jetbrains.kotlin.ir.types.IrType
@@ -27,7 +26,7 @@ import org.jetbrains.kotlin.ir.util.dump
 import org.jetbrains.kotlin.name.Name
 import java.util.*

-class JsDeclarationFactory : DeclarationFactory {
+class JsDeclarationFactory(private val irDeclarationFactory: IrDeclarationFactory) : DeclarationFactory {
    private val singletonFieldDescriptors = HashMap<IrClass, IrField>()
    private val outerThisFieldSymbols = HashMap<IrClass, IrField>()
    private val innerClassConstructors = HashMap<IrConstructor, IrConstructor>()
@@ -54,7 +53,7 @@ class JsDeclarationFactory : DeclarationFactory {
        val descriptor = WrappedFieldDescriptor()
        val symbol = IrFieldSymbolImpl(descriptor)

-        return IrFieldImpl(
+        return irDeclarationFactory.createField(
            UNDEFINED_OFFSET,
            UNDEFINED_OFFSET,
            origin,
@@ -89,7 +88,7 @@ class JsDeclarationFactory : DeclarationFactory {
        val descriptor = WrappedClassConstructorDescriptor(oldConstructor.descriptor.annotations, oldConstructor.descriptor.source)
        val symbol = IrConstructorSymbolImpl(descriptor)

-        val newConstructor = IrConstructorImpl(
+        val newConstructor = irDeclarationFactory.createConstructor(
            oldConstructor.startOffset,
            oldConstructor.endOffset,
            oldConstructor.origin,
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIntrinsics.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIntrinsics.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -13,29 +13,26 @@ import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
 import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.declarations.IrProperty
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
-import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
-import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.ir.factories.createExternalPackageFragment
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.defaultType
 import org.jetbrains.kotlin.ir.types.isLong
-import org.jetbrains.kotlin.ir.util.companionObject
 import org.jetbrains.kotlin.ir.util.constructors
 import org.jetbrains.kotlin.ir.util.findDeclaration
 import org.jetbrains.kotlin.ir.util.kotlinPackageFqn
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi2ir.findSingleFunction
-import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.util.capitalizeDecapitalize.toLowerCaseAsciiOnly
 import java.util.*

 class JsIntrinsics(private val irBuiltIns: IrBuiltIns, val context: JsIrBackendContext) {

    private val externalPackageFragmentSymbol = IrExternalPackageFragmentSymbolImpl(context.internalPackageFragmentDescriptor)
-    val externalPackageFragment = IrExternalPackageFragmentImpl(externalPackageFragmentSymbol)
+    val externalPackageFragment = context.irDeclarationFactory.createExternalPackageFragment(externalPackageFragmentSymbol)

    // TODO: Should we drop operator intrinsics in favor of IrDynamicOperatorExpression?

--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -27,8 +27,9 @@ import org.jetbrains.kotlin.ir.backend.js.lower.CallableReferenceKey
 import org.jetbrains.kotlin.ir.backend.js.lower.ConstructorPair
 import org.jetbrains.kotlin.ir.backend.js.utils.OperatorNames
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.createFile
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.types.impl.IrDynamicTypeImpl
@@ -43,6 +44,7 @@ class JsIrBackendContext(
    val module: ModuleDescriptor,
    override val irBuiltIns: IrBuiltIns,
    val symbolTable: SymbolTable,
+    override val irDeclarationFactory: IrDeclarationFactory,
    irModuleFragment: IrModuleFragment,
    val additionalExportedDeclarations: Set<FqName>,
    override val configuration: CompilerConfiguration, // TODO: remove configuration from backend context
@@ -68,7 +70,7 @@ class JsIrBackendContext(

    val internalPackageFragmentDescriptor = EmptyPackageFragmentDescriptor(builtIns.builtInsModule, FqName("kotlin.js.internal"))
    val implicitDeclarationFile by lazy {
-        IrFileImpl(object : SourceManager.FileEntry {
+        irDeclarationFactory.createFile(object : SourceManager.FileEntry {
            override val name = "<implicitDeclarations>"
            override val maxOffset = UNDEFINED_OFFSET

@@ -101,8 +103,8 @@ class JsIrBackendContext(
            implicitDeclarationFile.declarations += this
        }

-    override val sharedVariablesManager = JsSharedVariablesManager(irBuiltIns, implicitDeclarationFile)
-    override val declarationFactory = JsDeclarationFactory()
+    override val sharedVariablesManager = JsSharedVariablesManager(irBuiltIns, irDeclarationFactory, implicitDeclarationFile)
+    override val declarationFactory = JsDeclarationFactory(irDeclarationFactory)

    companion object {
        val KOTLIN_PACKAGE_FQN = FqName.fromSegments(listOf("kotlin"))
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsSharedVariablesManager.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsSharedVariablesManager.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -13,15 +13,12 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.backend.js.ir.JsIrBuilder
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrClassImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrVariableImpl
 import org.jetbrains.kotlin.ir.descriptors.*
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrGetValue
 import org.jetbrains.kotlin.ir.expressions.IrSetVariable
 import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.IrVariableSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrClassSymbolImpl
 import org.jetbrains.kotlin.ir.symbols.impl.IrConstructorSymbolImpl
@@ -32,7 +29,11 @@ import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
 import org.jetbrains.kotlin.ir.util.defaultType
 import org.jetbrains.kotlin.name.Name

-class JsSharedVariablesManager(val builtIns: IrBuiltIns, val implicitDeclarationsFile: IrPackageFragment) : SharedVariablesManager {
+class JsSharedVariablesManager(
+    val builtIns: IrBuiltIns,
+    private val irDeclarationFactory: IrDeclarationFactory,
+    val implicitDeclarationsFile: IrPackageFragment
+) : SharedVariablesManager {

    override fun declareSharedVariable(originalDeclaration: IrVariable): IrVariable {
        val valueType = originalDeclaration.type
@@ -51,7 +52,7 @@ class JsSharedVariablesManager(val builtIns: IrBuiltIns, val implicitDeclaration
                }

        val descriptor = WrappedVariableDescriptor()
-        return IrVariableImpl(
+        return irDeclarationFactory.createVariable(
            originalDeclaration.startOffset,
            originalDeclaration.endOffset,
            originalDeclaration.origin,
@@ -123,7 +124,7 @@ class JsSharedVariablesManager(val builtIns: IrBuiltIns, val implicitDeclaration

    private fun createClosureBoxClassDeclaration(): IrClass {
        val descriptor = WrappedClassDescriptor()
-        val declaration = IrClassImpl(
+        val declaration = irDeclarationFactory.createClass(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET, JsLoweredDeclarationOrigin.JS_CLOSURE_BOX_CLASS_DECLARATION, IrClassSymbolImpl(descriptor),
            Name.identifier(boxTypeName), ClassKind.CLASS, Visibilities.PUBLIC, Modality.FINAL,
            isCompanion = false, isInner = false, isData = false, isExternal = false, isInline = false, isExpect = false
@@ -146,7 +147,7 @@ class JsSharedVariablesManager(val builtIns: IrBuiltIns, val implicitDeclaration
        val descriptor = WrappedFieldDescriptor()
        val symbol = IrFieldSymbolImpl(descriptor)
        val fieldName = Name.identifier("v")
-        return IrFieldImpl(
+        return irDeclarationFactory.createField(
            UNDEFINED_OFFSET,
            UNDEFINED_OFFSET,
            DeclarationFactory.FIELD_FOR_OUTER_THIS,
@@ -169,7 +170,7 @@ class JsSharedVariablesManager(val builtIns: IrBuiltIns, val implicitDeclaration
        val descriptor = WrappedClassConstructorDescriptor()
        val symbol = IrConstructorSymbolImpl(descriptor)

-        val declaration = IrConstructorImpl(
+        val declaration = irDeclarationFactory.createConstructor(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET, JsLoweredDeclarationOrigin.JS_CLOSURE_BOX_CLASS_DECLARATION, symbol,
            Name.special("<init>"), Visibilities.PUBLIC, closureBoxClassDeclaration.defaultType,
            isInline = false, isExternal = false, isPrimary = true, isExpect = false
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/compiler.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/compiler.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -9,20 +9,14 @@ import com.intellij.openapi.project.Project
 import org.jetbrains.kotlin.backend.common.phaser.PhaseConfig
 import org.jetbrains.kotlin.backend.common.phaser.invokeToplevel
 import org.jetbrains.kotlin.config.CompilerConfiguration
-import org.jetbrains.kotlin.ir.backend.js.export.isExported
 import org.jetbrains.kotlin.ir.backend.js.lower.moveBodilessDeclarationsToSeparatePlace
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.IrModuleToJsTransformer
 import org.jetbrains.kotlin.ir.backend.js.utils.JsMainFunctionDetector
 import org.jetbrains.kotlin.ir.backend.js.utils.NameTables
-import org.jetbrains.kotlin.ir.backend.js.utils.isJsExport
-import org.jetbrains.kotlin.ir.declarations.IrDeclarationWithName
-import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
-import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.util.ExternalDependenciesGenerator
-import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
 import org.jetbrains.kotlin.ir.util.generateTypicalIrProviderList
-import org.jetbrains.kotlin.ir.util.isEffectivelyExternal
 import org.jetbrains.kotlin.ir.util.patchDeclarationParents
 import org.jetbrains.kotlin.library.KotlinLibrary
 import org.jetbrains.kotlin.library.resolver.KotlinLibraryResolveResult
@@ -50,6 +44,7 @@ fun compile(
    files: List<KtFile>,
    configuration: CompilerConfiguration,
    phaseConfig: PhaseConfig,
+    irDeclarationFactory: IrDeclarationFactory,
    allDependencies: KotlinLibraryResolveResult,
    friendDependencies: List<KotlinLibrary>,
    mainArguments: List<String>?,
@@ -58,13 +53,13 @@ fun compile(
    generateDceJs: Boolean = false
 ): CompilerResult {
    val (moduleFragment, dependencyModules, irBuiltIns, symbolTable, deserializer) =
-        loadIr(project, files, configuration, allDependencies, friendDependencies)
+        loadIr(project, files, configuration, irDeclarationFactory, allDependencies, friendDependencies)

    val moduleDescriptor = moduleFragment.descriptor

    val mainFunction = JsMainFunctionDetector.getMainFunctionOrNull(moduleFragment)

-    val context = JsIrBackendContext(moduleDescriptor, irBuiltIns, symbolTable, moduleFragment, exportedDeclarations, configuration)
+    val context = JsIrBackendContext(moduleDescriptor, irBuiltIns, symbolTable, irDeclarationFactory, moduleFragment, exportedDeclarations, configuration)

    // Load declarations referenced during `context` initialization
    dependencyModules.forEach {
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ir/IrBuilder.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ir/IrBuilder.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -11,10 +11,10 @@ import org.jetbrains.kotlin.descriptors.Visibility
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.*
 import org.jetbrains.kotlin.ir.descriptors.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.symbols.impl.*
 import org.jetbrains.kotlin.ir.types.IrType
@@ -22,6 +22,8 @@ import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.Variance

 object JsIrBuilder {
+    /// HACK
+    private val irDeclarationFactory = IrDeclarationFactory.DEFAULT

    object SYNTHESIZED_STATEMENT : IrStatementOriginImpl("SYNTHESIZED_STATEMENT")
    object SYNTHESIZED_DECLARATION : IrDeclarationOriginImpl("SYNTHESIZED_DECLARATION")
@@ -50,7 +52,7 @@ object JsIrBuilder {

    fun buildValueParameter(name: Name, index: Int, type: IrType, origin: IrDeclarationOrigin = SYNTHESIZED_DECLARATION): IrValueParameter {
        val descriptor = WrappedValueParameterDescriptor()
-        return IrValueParameterImpl(
+        return irDeclarationFactory.createValueParameter(
            UNDEFINED_OFFSET,
            UNDEFINED_OFFSET,
            origin,
@@ -68,7 +70,7 @@ object JsIrBuilder {

    fun buildTypeParameter(name: Name, index: Int, isReified: Boolean, variance: Variance = Variance.INVARIANT): IrTypeParameter {
        val descriptor = WrappedTypeParameterDescriptor()
-        return IrTypeParameterImpl(
+        return irDeclarationFactory.createTypeParameter(
            UNDEFINED_OFFSET,
            UNDEFINED_OFFSET,
            SYNTHESIZED_DECLARATION,
@@ -123,7 +125,7 @@ object JsIrBuilder {
        origin: IrDeclarationOrigin = SYNTHESIZED_DECLARATION
    ): IrSimpleFunction {
        val descriptor = WrappedSimpleFunctionDescriptor()
-        return IrFunctionImpl(
+        return irDeclarationFactory.createSimpleFunction(
            UNDEFINED_OFFSET,
            UNDEFINED_OFFSET,
            origin,
@@ -146,9 +148,9 @@ object JsIrBuilder {
    }

    fun buildAnonymousInitializer() =
-        IrAnonymousInitializerImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, SYNTHESIZED_DECLARATION, IrAnonymousInitializerSymbolImpl(
-            WrappedClassDescriptor()
-        ))
+        irDeclarationFactory.createAnonymousInitializer(
+            UNDEFINED_OFFSET, UNDEFINED_OFFSET, SYNTHESIZED_DECLARATION, IrAnonymousInitializerSymbolImpl(WrappedClassDescriptor())
+        )

    fun buildGetObjectValue(type: IrType, classSymbol: IrClassSymbol) =
        IrGetObjectValueImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, type, classSymbol)
@@ -201,7 +203,7 @@ object JsIrBuilder {
        initializer: IrExpression? = null
    ): IrVariable {
        val descriptor = WrappedVariableDescriptor()
-        return IrVariableImpl(
+        return irDeclarationFactory.createVariable(
            UNDEFINED_OFFSET,
            UNDEFINED_OFFSET,
            SYNTHESIZED_DECLARATION,
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/BridgesConstruction.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/BridgesConstruction.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -21,8 +21,8 @@ import org.jetbrains.kotlin.ir.backend.js.utils.functionSignature
 import org.jetbrains.kotlin.ir.backend.js.utils.getJsName
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.factories.createValueParameter
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.classifierOrNull
 import org.jetbrains.kotlin.ir.util.*
@@ -132,7 +132,9 @@ class BridgesConstruction(val context: CommonBackendContext) : ClassLoweringPass
            copyTypeParametersFrom(bridge)
            // TODO: should dispatch receiver be copied?
            dispatchReceiverParameter = bridge.dispatchReceiverParameter?.run {
-                IrValueParameterImpl(startOffset, endOffset, origin, descriptor, type, varargElementType).also { it.parent = this@apply }
+                context.irDeclarationFactory
+                    .createValueParameter(startOffset, endOffset, origin, descriptor, type, varargElementType)
+                    .also { it.parent = this@apply }
            }
            extensionReceiverParameter = bridge.extensionReceiverParameter?.copyTo(this)
            valueParameters += bridge.valueParameters.map { p -> p.copyTo(this) }
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/CallableReferenceLowering.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/CallableReferenceLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -15,8 +15,6 @@ import org.jetbrains.kotlin.ir.backend.js.ir.JsIrBuilder
 import org.jetbrains.kotlin.ir.backend.js.utils.Namer
 import org.jetbrains.kotlin.ir.backend.js.utils.asString
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrTypeParameterImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedTypeParameterDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
@@ -429,7 +427,7 @@ class CallableReferenceLowering(val context: JsIrBackendContext) : FileLoweringP

        for ((i, p) in boundValueParameters.withIndex()) {
            val descriptor = WrappedValueParameterDescriptor()
-            factoryDeclaration.valueParameters += IrValueParameterImpl(
+            factoryDeclaration.valueParameters += context.irDeclarationFactory.createValueParameter(
                p.startOffset,
                p.endOffset,
                p.origin,
@@ -451,7 +449,7 @@ class CallableReferenceLowering(val context: JsIrBackendContext) : FileLoweringP

        for (t in typeParameters) {
            val descriptor = WrappedTypeParameterDescriptor()
-            factoryDeclaration.typeParameters += IrTypeParameterImpl(
+            factoryDeclaration.typeParameters += context.irDeclarationFactory.createTypeParameter(
                t.startOffset,
                t.endOffset,
                t.origin,
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/ClassReferenceLowering.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/ClassReferenceLowering.kt
@@ -26,7 +26,7 @@ import org.jetbrains.kotlin.ir.util.isFunction
 import org.jetbrains.kotlin.ir.util.isThrowable
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.types.*
+import org.jetbrains.kotlin.types.Variance

 class ClassReferenceLowering(val context: JsIrBackendContext) : FileLoweringPass {
    private val intrinsics = context.intrinsics
@@ -224,7 +224,7 @@ class ClassReferenceLowering(val context: JsIrBackendContext) : FileLoweringPass
    }

    override fun lower(irFile: IrFile) {
-        irFile.transformChildrenVoid(object : IrElementTransformerVoidWithContext() {
+        irFile.transformChildrenVoid(object : IrElementTransformerVoidWithContext(context) {
            override fun visitGetClass(expression: IrGetClass) =
                callGetKClassFromExpression(
                    returnType = expression.type,
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/CreateScriptFunctionsPhase.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/CreateScriptFunctionsPhase.kt
@@ -13,7 +13,6 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
@@ -95,11 +94,11 @@ class CreateScriptFunctionsPhase(val context: CommonBackendContext) : FileLoweri
        return (irScript.statements.lastOrNull() as? IrExpression)?.type ?: context.irBuiltIns.unitType
    }

-    private fun createFunction(irScript: IrScript, name: String, returnType: IrType): IrFunctionImpl {
+    private fun createFunction(irScript: IrScript, name: String, returnType: IrType): IrSimpleFunction {
        val (startOffset, endOffset) = getFunctionBodyOffsets(irScript)
        val descriptor = WrappedSimpleFunctionDescriptor()

-        return IrFunctionImpl(
+        return context.irDeclarationFactory.createSimpleFunction(
            startOffset, endOffset, SCRIPT_FUNCTION,
            IrSimpleFunctionSymbolImpl(descriptor),
            Name.identifier(name),
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/EnumClassLowering.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/EnumClassLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -21,8 +21,6 @@ import org.jetbrains.kotlin.ir.backend.js.utils.toJsArrayLiteral
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.buildField
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedFieldDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
@@ -67,7 +65,7 @@ class EnumUsageLowering(val context: JsIrBackendContext) : FileLoweringPass {
        val descriptor = WrappedFieldDescriptor()
        val symbol = IrFieldSymbolImpl(descriptor)
        return entry.run {
-            IrFieldImpl(
+            context.irDeclarationFactory.createField(
                startOffset, endOffset, origin, symbol, name, irClass.defaultType, Visibilities.PUBLIC,
                isFinal = false, isExternal = true, isStatic = true,
                isFakeOverride = origin == IrDeclarationOrigin.FAKE_OVERRIDE
@@ -189,7 +187,7 @@ class EnumClassConstructorTransformer(val context: CommonBackendContext, private
        val loweredConstructorDescriptor = WrappedClassConstructorDescriptor()
        val loweredConstructorSymbol = IrConstructorSymbolImpl(loweredConstructorDescriptor)

-        return IrConstructorImpl(
+        return context.irDeclarationFactory.createConstructor(
            enumConstructor.startOffset,
            enumConstructor.endOffset,
            enumConstructor.origin,
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/MoveBodilessDeclarationsToSeparatePlace.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/MoveBodilessDeclarationsToSeparatePlace.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -11,8 +11,6 @@ import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.utils.getJsModule
 import org.jetbrains.kotlin.ir.backend.js.utils.getJsQualifier
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
 import org.jetbrains.kotlin.ir.symbols.IrExternalPackageFragmentSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFileSymbol
 import org.jetbrains.kotlin.ir.util.UniqId
@@ -82,7 +80,7 @@ private class DescriptorlessIrFileSymbol : IrFileSymbol {

 fun moveBodilessDeclarationsToSeparatePlace(context: JsIrBackendContext, module: IrModuleFragment) {

-    val bodilessBuiltInsPackageFragment = IrExternalPackageFragmentImpl(
+    val bodilessBuiltInsPackageFragment = context.irDeclarationFactory.createExternalPackageFragment(
        DescriptorlessExternalPackageFragmentSymbol(),
        FqName("kotlin")
    )
@@ -108,9 +106,11 @@ fun moveBodilessDeclarationsToSeparatePlace(context: JsIrBackendContext, module:
    fun lowerFile(irFile: IrFile): IrFile? {
        val externalPackageFragment by lazy {
            context.externalPackageFragment.getOrPut(irFile.symbol) {
-                IrFileImpl(fileEntry = irFile.fileEntry, fqName = irFile.fqName, symbol = DescriptorlessIrFileSymbol()).also {
-                    it.annotations += irFile.annotations
-                }
+                context.irDeclarationFactory
+                    .createFile(fileEntry = irFile.fileEntry, fqName = irFile.fqName, symbol = DescriptorlessIrFileSymbol())
+                    .also {
+                        it.annotations += irFile.annotations
+                    }
            }
        }

--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/PrivateMembersLowering.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/PrivateMembersLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -12,8 +12,6 @@ import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
@@ -190,7 +188,7 @@ class PrivateMembersLowering(val context: JsIrBackendContext) : FileLoweringPass
            val descriptor = WrappedSimpleFunctionDescriptor()
            val symbol = IrSimpleFunctionSymbolImpl(descriptor)
            val staticFunction = function.run {
-                IrFunctionImpl(
+                context.irDeclarationFactory.createSimpleFunction(
                    startOffset, endOffset, origin,
                    symbol, name, visibility, modality,
                    returnType,
@@ -209,7 +207,7 @@ class PrivateMembersLowering(val context: JsIrBackendContext) : FileLoweringPass
            staticFunction.extensionReceiverParameter = function.extensionReceiverParameter?.copyTo(staticFunction)
            val thisDesc = WrappedValueParameterDescriptor()
            val thisSymbol = IrValueParameterSymbolImpl(thisDesc)
-            staticFunction.valueParameters += IrValueParameterImpl(
+            staticFunction.valueParameters += context.irDeclarationFactory.createValueParameter(
                UNDEFINED_OFFSET,
                UNDEFINED_OFFSET,
                STATIC_THIS_PARAMETER,
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendContext.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendContext.kt
@@ -32,6 +32,7 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrFunctionReference
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.SymbolTable
@@ -48,6 +49,7 @@ class JvmBackendContext(
    irModuleFragment: IrModuleFragment,
    private val symbolTable: SymbolTable,
    val phaseConfig: PhaseConfig,
+    override val irDeclarationFactory: IrDeclarationFactory,
    // If the JVM fqname of a class differs from what is implied by its parent, e.g. if it's a file class
    // annotated with @JvmPackageName, the correct name is recorded here.
    internal val classNameOverride: MutableMap<IrClass, JvmClassName>
@@ -61,8 +63,8 @@ class JvmBackendContext(
    val typeMapper = IrTypeMapper(this)
    val methodSignatureMapper = MethodSignatureMapper(this)

-    override val declarationFactory: JvmDeclarationFactory = JvmDeclarationFactory(methodSignatureMapper)
-    override val sharedVariablesManager = JvmSharedVariablesManager(state.module, builtIns, irBuiltIns)
+    override val declarationFactory: JvmDeclarationFactory = JvmDeclarationFactory(methodSignatureMapper, irDeclarationFactory)
+    override val sharedVariablesManager = JvmSharedVariablesManager(state.module, builtIns, irBuiltIns, irDeclarationFactory)

    override val ir = JvmIr(irModuleFragment, this.symbolTable)

--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendFacade.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmBackendFacade.kt
@@ -15,6 +15,7 @@ import org.jetbrains.kotlin.backend.jvm.serialization.JvmMangler
 import org.jetbrains.kotlin.codegen.state.GenerationState
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.types.defaultType
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.psi.KtFile
@@ -22,10 +23,18 @@ import org.jetbrains.kotlin.psi2ir.Psi2IrTranslator
 import org.jetbrains.kotlin.psi2ir.PsiSourceManager

 object JvmBackendFacade {
-    fun doGenerateFiles(files: Collection<KtFile>, state: GenerationState, phaseConfig: PhaseConfig) {
+    fun doGenerateFiles(
+        files: Collection<KtFile>,
+        state: GenerationState,
+        phaseConfig: PhaseConfig,
+        irDeclarationFactory: IrDeclarationFactory
+    ) {
        val extensions = JvmGeneratorExtensions()
        val psi2ir = Psi2IrTranslator(state.languageVersionSettings, mangler = JvmMangler)
-        val psi2irContext = psi2ir.createGeneratorContext(state.module, state.bindingContext, extensions = extensions)
+        val psi2irContext = psi2ir.createGeneratorContext(
+            state.module, state.bindingContext,
+            extensions = extensions, irDeclarationFactory = irDeclarationFactory
+        )

        for (extension in IrGenerationExtension.getInstances(state.project)) {
            psi2ir.addPostprocessingStep { module ->
@@ -37,7 +46,8 @@ object JvmBackendFacade {
                        psi2irContext.languageVersionSettings,
                        psi2irContext.symbolTable,
                        psi2irContext.typeTranslator,
-                        psi2irContext.irBuiltIns
+                        psi2irContext.irBuiltIns,
+                        psi2irContext.irDeclarationFactory
                    )
                )
            }
@@ -49,7 +59,8 @@ object JvmBackendFacade {
        )
        val irModuleFragment = psi2ir.generateModuleFragment(psi2irContext, files, irProviders = irProviders, expectDescriptorToSymbol = null)
        doGenerateFilesInternal(
-            state, irModuleFragment, psi2irContext.symbolTable, psi2irContext.sourceManager, phaseConfig, irProviders, extensions
+            state, irModuleFragment, psi2irContext.symbolTable, psi2irContext.sourceManager,
+            phaseConfig, irDeclarationFactory, irProviders, extensions
        )
    }

@@ -59,11 +70,13 @@ object JvmBackendFacade {
        symbolTable: SymbolTable,
        sourceManager: PsiSourceManager,
        phaseConfig: PhaseConfig,
+        irDeclarationFactory: IrDeclarationFactory,
        irProviders: List<IrProvider>,
        extensions: JvmGeneratorExtensions
    ) {
        val context = JvmBackendContext(
-            state, sourceManager, irModuleFragment.irBuiltins, irModuleFragment, symbolTable, phaseConfig, extensions.classNameOverride
+            state, sourceManager, irModuleFragment.irBuiltins, irModuleFragment,
+            symbolTable, phaseConfig, irDeclarationFactory, extensions.classNameOverride
        )
        /* JvmBackendContext creates new unbound symbols, have to resolve them. */
        ExternalDependenciesGenerator(symbolTable, irProviders).generateUnboundSymbolsAsDependencies()
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmIrCodegenFactory.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmIrCodegenFactory.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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
@@ -24,6 +13,7 @@ import org.jetbrains.kotlin.codegen.PackageCodegenImpl
 import org.jetbrains.kotlin.codegen.state.GenerationState
 import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.util.ExternalDependenciesGenerator
 import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.ir.util.generateTypicalIrProviderList
@@ -31,10 +21,13 @@ import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi2ir.PsiSourceManager

-class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory {
+class JvmIrCodegenFactory(
+    private val phaseConfig: PhaseConfig,
+    private val irDeclarationFactory: IrDeclarationFactory
+) : CodegenFactory {

    override fun generateModule(state: GenerationState, files: Collection<KtFile>) {
-        JvmBackendFacade.doGenerateFiles(files, state, phaseConfig)
+        JvmBackendFacade.doGenerateFiles(files, state, phaseConfig, irDeclarationFactory)
    }

    fun generateModuleInFrontendIRMode(
@@ -46,7 +39,7 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory
        )
        ExternalDependenciesGenerator(symbolTable, irProviders).generateUnboundSymbolsAsDependencies()
        JvmBackendFacade.doGenerateFilesInternal(
-            state, irModuleFragment, symbolTable, sourceManager, phaseConfig, irProviders, extensions
+            state, irModuleFragment, symbolTable, sourceManager, phaseConfig, irDeclarationFactory, irProviders, extensions
        )
    }

@@ -55,7 +48,7 @@ class JvmIrCodegenFactory(private val phaseConfig: PhaseConfig) : CodegenFactory

        return object : PackageCodegen {
            override fun generate() {
-                JvmBackendFacade.doGenerateFiles(files, state, phaseConfig)
+                JvmBackendFacade.doGenerateFiles(files, state, phaseConfig, irDeclarationFactory)
            }

            override fun getPackageFragment(): PackageFragmentDescriptor {
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmSymbols.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmSymbols.kt
@@ -17,7 +17,7 @@ import org.jetbrains.kotlin.ir.builders.declarations.*
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrPackageFragment
-import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
+import org.jetbrains.kotlin.ir.factories.createExternalPackageFragment
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
 import org.jetbrains.kotlin.ir.types.*
@@ -74,7 +74,8 @@ class JvmSymbols(
    }

    private fun createPackage(fqName: FqName): IrPackageFragment =
-        IrExternalPackageFragmentImpl(IrExternalPackageFragmentSymbolImpl(EmptyPackageFragmentDescriptor(context.state.module, fqName)))
+        context.irDeclarationFactory.createExternalPackageFragment(
+            IrExternalPackageFragmentSymbolImpl(EmptyPackageFragmentDescriptor(context.state.module, fqName)))

    private fun createClass(
        fqName: FqName,
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/ClassCodegen.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/ClassCodegen.kt
@@ -333,7 +333,7 @@ open class ClassCodegen protected constructor(

        AnnotationCodegen(this, context, fv::visitAnnotation).genAnnotations(field, fieldType)

-        val descriptor = field.metadata?.descriptor
+        val descriptor = (field.metadata as MetadataSource.Property?)?.descriptor
        if (descriptor != null) {
            state.globalSerializationBindings.put(JvmSerializationBindings.FIELD_FOR_PROPERTY, descriptor, fieldType to fieldName)
        }
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/CoroutineCodegen.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/CoroutineCodegen.kt
@@ -22,7 +22,6 @@ import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedFunctionDescriptorWithContainerSource
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrCall
@@ -45,7 +44,6 @@ import org.jetbrains.kotlin.resolve.jvm.jvmSignature.JvmMethodGenericSignature
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DescriptorWithContainerSource
 import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.org.objectweb.asm.MethodVisitor
-import org.jetbrains.org.objectweb.asm.Opcodes
 import org.jetbrains.org.objectweb.asm.Type
 import org.jetbrains.org.objectweb.asm.commons.InstructionAdapter

@@ -159,7 +157,7 @@ private fun IrFunction.suspendFunctionView(context: JvmBackendContext): IrFuncti
            WrappedFunctionDescriptorWithContainerSource(originalDescriptor.containerSource!!)
        else
            WrappedSimpleFunctionDescriptor(sourceElement = originalDescriptor.source)
-    return IrFunctionImpl(
+    return context.irDeclarationFactory.createSimpleFunction(
        startOffset, endOffset,
        if (origin == JvmLoweredDeclarationOrigin.FOR_INLINE_STATE_MACHINE_TEMPLATE_CAPTURES_CROSSINLINE)
            JvmLoweredDeclarationOrigin.FOR_INLINE_STATE_MACHINE_TEMPLATE_CAPTURES_CROSSINLINE_VIEW
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/descriptors/JvmDeclarationFactory.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/descriptors/JvmDeclarationFactory.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -20,11 +20,11 @@ import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.declarations.buildField
 import org.jetbrains.kotlin.ir.builders.setSourceRange
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.*
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.impl.*
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.*
@@ -34,7 +34,8 @@ import org.jetbrains.kotlin.name.Name
 import java.util.*

 class JvmDeclarationFactory(
-    private val methodSignatureMapper: MethodSignatureMapper
+    private val methodSignatureMapper: MethodSignatureMapper,
+    private val irDeclarationFactory: IrDeclarationFactory
 ) : DeclarationFactory {
    private val singletonFieldDeclarations = HashMap<IrSymbolOwner, IrField>()
    private val interfaceCompanionFieldDeclarations = HashMap<IrSymbolOwner, IrField>()
@@ -84,7 +85,7 @@ class JvmDeclarationFactory(

    private fun createInnerClassConstructorWithOuterThisParameter(oldConstructor: IrConstructor): IrConstructor {
        val newDescriptor = WrappedClassConstructorDescriptor(oldConstructor.descriptor.annotations)
-        return IrConstructorImpl(
+        return irDeclarationFactory.createConstructor(
            oldConstructor.startOffset,
            oldConstructor.endOffset,
            oldConstructor.origin,
@@ -105,7 +106,7 @@ class JvmDeclarationFactory(

            val outerThisType = oldConstructor.parentAsClass.parentAsClass.defaultType
            val outerThisDescriptor = WrappedValueParameterDescriptor()
-            val outerThisValueParameter = IrValueParameterImpl(
+            val outerThisValueParameter = irDeclarationFactory.createValueParameter(
                UNDEFINED_OFFSET, UNDEFINED_OFFSET, JvmLoweredDeclarationOrigin.FIELD_FOR_OUTER_THIS,
                IrValueParameterSymbolImpl(outerThisDescriptor),
                Name.identifier(AsmUtil.CAPTURED_THIS_FIELD),
@@ -181,7 +182,7 @@ class JvmDeclarationFactory(
                initializer = oldField.initializer
                    ?.replaceThisByStaticReference(this@JvmDeclarationFactory, oldParent, oldParent.thisReceiver!!)
                    ?.patchDeclarationParents(this) as IrExpressionBody?
-                (this as IrFieldImpl).metadata = oldField.metadata
+                this.metadata = oldField.metadata
            }
        }
    }
@@ -218,7 +219,7 @@ class JvmDeclarationFactory(
    fun getDefaultImplsClass(interfaceClass: IrClass): IrClass =
        defaultImplsClasses.getOrPut(interfaceClass) {
            val descriptor = WrappedClassDescriptor()
-            IrClassImpl(
+            irDeclarationFactory.createClass(
                interfaceClass.startOffset, interfaceClass.endOffset,
                JvmLoweredDeclarationOrigin.DEFAULT_IMPLS,
                IrClassSymbolImpl(descriptor),
@@ -245,7 +246,7 @@ class JvmDeclarationFactory(
            val irClass = fakeOverride.parentAsClass
            val descriptor = DescriptorsToIrRemapper.remapDeclaredSimpleFunction(fakeOverride.descriptor)
            with(fakeOverride) {
-                IrFunctionImpl(
+                irDeclarationFactory.createSimpleFunction(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET, JvmLoweredDeclarationOrigin.DEFAULT_IMPLS_BRIDGE,
                    IrSimpleFunctionSymbolImpl(descriptor),
                    name, visibility, modality, returnType,
@@ -267,7 +268,7 @@ class JvmDeclarationFactory(
                        // If both setter and getter are present, original property will be duplicated.
                        val newPropertyDescriptor = DescriptorsToIrRemapper.remapDeclaredProperty(fakeOverrideProperty.descriptor)
                        correspondingPropertySymbol = with(fakeOverrideProperty) {
-                            IrPropertyImpl(
+                            irDeclarationFactory.createProperty(
                                UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                                IrDeclarationOrigin.DEFINED, IrPropertySymbolImpl(newPropertyDescriptor),
                                name, visibility, modality, isVar, isConst, isLateinit, isDelegated,
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/descriptors/SharedVariablesManager.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/descriptors/SharedVariablesManager.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -17,14 +17,13 @@ import org.jetbrains.kotlin.ir.builders.declarations.buildConstructor
 import org.jetbrains.kotlin.ir.builders.declarations.buildField
 import org.jetbrains.kotlin.ir.builders.declarations.buildValueParameter
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrTypeParameterImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrVariableImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.descriptors.WrappedTypeParameterDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedVariableDescriptor
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.createExternalPackageFragment
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrVariableSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
@@ -45,9 +44,10 @@ private val SHARED_VARIABLE_CONSTRUCTOR_CALL_ORIGIN = object : IrStatementOrigin
 class JvmSharedVariablesManager(
    module: ModuleDescriptor,
    val builtIns: KotlinBuiltIns,
-    val irBuiltIns: IrBuiltIns
+    val irBuiltIns: IrBuiltIns,
+    val irDeclarationFactory: IrDeclarationFactory
 ) : SharedVariablesManager {
-    private val jvmInternalPackage = IrExternalPackageFragmentImpl(
+    private val jvmInternalPackage = irDeclarationFactory.createExternalPackageFragment(
        IrExternalPackageFragmentSymbolImpl(
            EmptyPackageFragmentDescriptor(module, FqName("kotlin.jvm.internal"))
        )
@@ -119,7 +119,7 @@ class JvmSharedVariablesManager(
        }.apply {
            val irClass = this
            typeParameters.add(
-                IrTypeParameterImpl(
+                irDeclarationFactory.createTypeParameter(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    SHARED_VARIABLE_ORIGIN,
                    IrTypeParameterSymbolImpl(WrappedTypeParameterDescriptor()),
@@ -182,7 +182,7 @@ class JvmSharedVariablesManager(
            }
        }

-        return IrVariableImpl(
+        return irDeclarationFactory.createVariable(
            originalDeclaration.startOffset, originalDeclaration.endOffset, originalDeclaration.origin,
            IrVariableSymbolImpl(WrappedVariableDescriptor()),
            originalDeclaration.name,
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/ir/IrInlineReferenceLocator.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/ir/IrInlineReferenceLocator.kt
@@ -15,7 +15,7 @@ import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid

-internal open class IrInlineReferenceLocator(private val context: JvmBackendContext) : IrElementVisitorVoidWithContext() {
+internal open class IrInlineReferenceLocator(override val context: JvmBackendContext) : IrElementVisitorVoidWithContext(context) {
    val inlineReferences = mutableSetOf<IrCallableReference>()

    // For crossinline lambdas, the call site is null as it's probably in a separate class somewhere.
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/ir/IrUtils.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/ir/IrUtils.kt
@@ -126,7 +126,7 @@ class JvmIrBuilder(
    endOffset: Int = UNDEFINED_OFFSET
 ) : IrBuilderWithScope(
    IrLoweringContext(backendContext),
-    Scope(symbol),
+    Scope(symbol, backendContext.irDeclarationFactory),
    startOffset,
    endOffset
 ) {
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/AddContinuationLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/AddContinuationLowering.kt
@@ -64,7 +64,7 @@ private class AddContinuationLowering(private val context: JvmBackendContext) :
        for (lambda in suspendLambdas) {
            (lambda.function.parent as IrDeclarationContainer).declarations.remove(lambda.function)
        }
-        irFile.transformChildrenVoid(object : IrElementTransformerVoidWithContext() {
+        irFile.transformChildrenVoid(object : IrElementTransformerVoidWithContext(context) {
            override fun visitFunctionReference(expression: IrFunctionReference): IrExpression {
                if (!expression.isSuspend)
                    return expression
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/AdditionalClassAnnotationLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/AdditionalClassAnnotationLowering.kt
@@ -21,8 +21,6 @@ import org.jetbrains.kotlin.ir.builders.declarations.buildClass
 import org.jetbrains.kotlin.ir.builders.declarations.buildConstructor
 import org.jetbrains.kotlin.ir.builders.declarations.buildValueParameter
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrEnumEntryImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedEnumEntryDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrConstructorCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
@@ -31,6 +29,7 @@ import org.jetbrains.kotlin.ir.expressions.IrVararg
 import org.jetbrains.kotlin.ir.expressions.impl.IrConstructorCallImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetEnumValueImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrVarargImpl
+import org.jetbrains.kotlin.ir.factories.createExternalPackageFragment
 import org.jetbrains.kotlin.ir.symbols.impl.IrEnumEntrySymbolImpl
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
 import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
@@ -54,7 +53,7 @@ private class AdditionalClassAnnotationLowering(private val context: JvmBackendC

    // TODO: import IR structures from the library?

-    private val annotationPackage: IrPackageFragment = IrExternalPackageFragmentImpl(
+    private val annotationPackage: IrPackageFragment = context.irDeclarationFactory.createExternalPackageFragment(
        IrExternalPackageFragmentSymbolImpl(
            EmptyPackageFragmentDescriptor(
                context.ir.irModule.descriptor,
@@ -87,7 +86,7 @@ private class AdditionalClassAnnotationLowering(private val context: JvmBackendC
        returnType = annotationClass.defaultType
    }

-    private fun buildEnumEntry(enumClass: IrClass, entryName: String): IrEnumEntry = IrEnumEntryImpl(
+    private fun buildEnumEntry(enumClass: IrClass, entryName: String): IrEnumEntry = context.irDeclarationFactory.createEnumEntry(
        UNDEFINED_OFFSET, UNDEFINED_OFFSET, IrDeclarationOrigin.IR_EXTERNAL_JAVA_DECLARATION_STUB,
        IrEnumEntrySymbolImpl(WrappedEnumEntryDescriptor()),
        Name.identifier(entryName)
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/AnonymousObjectSuperConstructorLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/AnonymousObjectSuperConstructorLowering.kt
@@ -54,7 +54,7 @@ internal val anonymousObjectSuperConstructorPhase = makeIrFilePhase(
 // attempts to read them from fields, causing a bytecode validation error.
 //
 // (TODO fix the inliner instead. Then keep this code for one more version for backwards compatibility.)
-private class AnonymousObjectSuperConstructorLowering(val context: JvmBackendContext) : IrElementTransformerVoidWithContext(),
+private class AnonymousObjectSuperConstructorLowering(context: JvmBackendContext) : IrElementTransformerVoidWithContext(context),
    FileLoweringPass {
    override fun lower(irFile: IrFile) {
        irFile.transformChildrenVoid()
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/BridgeLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/BridgeLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -24,8 +24,6 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedReceiverParameterDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
@@ -209,7 +207,7 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass

    private fun IrSimpleFunction.copyRenamingTo(newName: Name): IrSimpleFunction =
        WrappedSimpleFunctionDescriptor(descriptor.annotations).let { newDescriptor ->
-            IrFunctionImpl(
+            context.irDeclarationFactory.createSimpleFunction(
                startOffset, endOffset, origin,
                IrSimpleFunctionSymbolImpl(newDescriptor),
                newName,
@@ -238,7 +236,7 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass

        val visibility = if (signatureFunction.visibility === Visibilities.INTERNAL) Visibilities.PUBLIC else signatureFunction.visibility
        val descriptor = WrappedSimpleFunctionDescriptor()
-        return IrFunctionImpl(
+        return context.irDeclarationFactory.createSimpleFunction(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET,
            origin,
            IrSimpleFunctionSymbolImpl(descriptor),
@@ -389,7 +387,7 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass
        else
            WrappedSimpleFunctionDescriptor(descriptor.annotations).let { wrappedDescriptor ->
                val newOrigin = if (origin == IrDeclarationOrigin.FAKE_OVERRIDE) IrDeclarationOrigin.DEFINED else origin
-                IrFunctionImpl(
+                context.irDeclarationFactory.createSimpleFunction(
                    startOffset, endOffset, newOrigin,
                    IrSimpleFunctionSymbolImpl(wrappedDescriptor),
                    Name.identifier(getJvmName()),
@@ -416,7 +414,7 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass
        } else {
            WrappedValueParameterDescriptor(this.descriptor.annotations)
        }
-        return IrValueParameterImpl(
+        return context.irDeclarationFactory.createValueParameter(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET,
            IrDeclarationOrigin.BRIDGE,
            IrValueParameterSymbolImpl(descriptor),
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/CallableReferenceLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/CallableReferenceLowering.kt
@@ -25,7 +25,6 @@ import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.*
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrClassImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrClassReferenceImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrFunctionReferenceImpl
@@ -46,7 +45,9 @@ internal val callableReferencePhase = makeIrFilePhase(


 // Originally copied from K/Native
-internal class CallableReferenceLowering(private val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+internal class CallableReferenceLowering(
+    override val context: JvmBackendContext
+) : FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    // This pass ignores suspend function references and function references used in inline arguments to inline functions.
    private val ignoredFunctionReferences = mutableSetOf<IrCallableReference>()

@@ -146,7 +147,7 @@ internal class CallableReferenceLowering(private val context: JvmBackendContext)
            createImplicitParameterDeclarationWithWrappedDescriptor()
            copyAttributes(irFunctionReference)
            if (isLambda) {
-                (this as IrClassImpl).metadata = irFunctionReference.symbol.owner.metadata
+                this.metadata = irFunctionReference.symbol.owner.metadata
            }
        }

--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/CheckNotNullLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/CheckNotNullLowering.kt
@@ -24,7 +24,9 @@ internal val checkNotNullPhase = makeIrFilePhase(
    description = "Lower calls to the CHECK_NOT_NULL intrinsic, which are generated by psi2ir for \"!!\" expressions."
 )

-private class CheckNotNullLowering(private val backendContext: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+private class CheckNotNullLowering(
+    private val backendContext: JvmBackendContext
+) : FileLoweringPass, IrElementTransformerVoidWithContext(backendContext) {
    override fun lower(irFile: IrFile) = irFile.transformChildrenVoid()

    override fun visitCall(expression: IrCall): IrExpression {
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/CollectionStubMethodLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/CollectionStubMethodLowering.kt
@@ -1,6 +1,6 @@
 /*
- * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
+ * 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
@@ -20,7 +20,6 @@ import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.declarations.IrValueParameter
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
@@ -104,7 +103,7 @@ private class CollectionStubMethodLowering(val context: JvmBackendContext) : Cla
    private fun IrValueParameter.copyWithSubstitution(target: IrSimpleFunction, substitutionMap: Map<IrTypeParameterSymbol, IrType>)
            : IrValueParameter {
        val descriptor = WrappedValueParameterDescriptor(this.descriptor.annotations)
-        return IrValueParameterImpl(
+        return context.irDeclarationFactory.createValueParameter(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET,
            IrDeclarationOrigin.IR_BUILTINS_STUB,
            IrValueParameterSymbolImpl(descriptor),
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/EnumClassLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/EnumClassLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -18,9 +18,6 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedFieldDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
@@ -59,7 +56,7 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP
    private inner class EnumClassTransformer(val irClass: IrClass) {
        private val enumEntryOrdinals = TObjectIntHashMap<IrEnumEntry>()
        private val enumEntryClassToEntry = HashMap<IrClass, IrEnumEntry>()
-        private val loweredEnumConstructors = HashMap<IrConstructorSymbol, IrConstructorImpl>()
+        private val loweredEnumConstructors = HashMap<IrConstructorSymbol, IrConstructor>()
        private val loweredEnumConstructorParameters = HashMap<IrValueParameterSymbol, IrValueParameter>()
        private val enumEntriesByField = HashMap<IrField, IrEnumEntry>()
        private val enumEntryFields = ArrayList<IrField>()
@@ -133,7 +130,7 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP
            enumClass: IrClass
        ): IrConstructor {
            val descriptor = WrappedClassConstructorDescriptor(enumConstructor.descriptor.annotations, enumConstructor.descriptor.source)
-            return IrConstructorImpl(
+            return context.irDeclarationFactory.createConstructor(
                enumConstructor.startOffset, enumConstructor.endOffset,
                enumConstructor.origin,
                IrConstructorSymbolImpl(descriptor),
@@ -168,7 +165,7 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP

        private fun makeNameValueParameter(constructor: IrConstructor): IrValueParameter {
            val descriptor = WrappedValueParameterDescriptor()
-            return IrValueParameterImpl(
+            return context.irDeclarationFactory.createValueParameter(
                UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                JvmLoweredDeclarationOrigin.ENUM_CONSTRUCTOR_SYNTHETIC_PARAMETER,
                IrValueParameterSymbolImpl(descriptor),
@@ -186,7 +183,7 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP

        private fun makeOrdinalValueParameter(constructor: IrConstructor): IrValueParameter {
            val descriptor = WrappedValueParameterDescriptor()
-            return IrValueParameterImpl(
+            return context.irDeclarationFactory.createValueParameter(
                UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                JvmLoweredDeclarationOrigin.ENUM_CONSTRUCTOR_SYNTHETIC_PARAMETER,
                IrValueParameterSymbolImpl(descriptor),
@@ -251,14 +248,14 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP
                }


-        private fun createSyntheticValuesFieldDeclaration(): IrFieldImpl {
+        private fun createSyntheticValuesFieldDeclaration(): IrField {
            val valuesArrayType = context.irBuiltIns.arrayClass.typeWith(irClass.defaultType)

            val irValuesInitializer = createSyntheticValuesFieldInitializerExpression()

            val descriptor = WrappedFieldDescriptor()
            // TODO: mark ACC_SYNTHETIC
-            return IrFieldImpl(
+            return context.irDeclarationFactory.createField(
                UNDEFINED_OFFSET, UNDEFINED_OFFSET, IrDeclarationOrigin.FIELD_FOR_ENUM_VALUES,
                IrFieldSymbolImpl(descriptor),
                Name.identifier("\$VALUES"),
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/FakeInliningLocalVariablesLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/FakeInliningLocalVariablesLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -32,7 +32,7 @@ internal val fakeInliningLocalVariablesLowering = makeIrFilePhase(
    description = "Add fake locals to identify the range of inlined functions and lambdas"
 )

-internal class FakeInliningLocalVariablesLowering(val context: JvmBackendContext) : IrInlineReferenceLocator(context), FileLoweringPass {
+internal class FakeInliningLocalVariablesLowering(context: JvmBackendContext) : IrInlineReferenceLocator(context), FileLoweringPass {
    override fun lower(irFile: IrFile) {
        irFile.acceptVoid(this)
    }
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/FileClassLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/FileClassLowering.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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
@@ -26,7 +15,6 @@ import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.fileClasses.JvmFileClassUtil
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrClassImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassDescriptor
 import org.jetbrains.kotlin.ir.symbols.impl.IrClassSymbolImpl
 import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
@@ -75,7 +63,7 @@ private class FileClassLowering(val context: JvmBackendContext) : FileLoweringPa
            ?: throw AssertionError("Unexpected file entry: $fileEntry")
        val fileClassInfo = JvmFileClassUtil.getFileClassInfoNoResolve(ktFile)
        val descriptor = WrappedClassDescriptor(sourceElement = KotlinSourceElement(ktFile))
-        return IrClassImpl(
+        return context.irDeclarationFactory.createClass(
            0, fileEntry.maxOffset,
            IrDeclarationOrigin.FILE_CLASS,
            symbol = IrClassSymbolImpl(descriptor),
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/FunctionNVarargBridgeLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/FunctionNVarargBridgeLowering.kt
@@ -41,8 +41,8 @@ internal val functionNVarargBridgePhase = makeIrFilePhase(
 // inherit from the generic FunctionN class which has a vararg invoke method. This phase
 // adds a bridge method for such large arity functions, which checks the number of arguments
 // dynamically.
-private class FunctionNVarargBridgeLowering(val context: JvmBackendContext) :
-    FileLoweringPass, IrElementTransformerVoidWithContext() {
+private class FunctionNVarargBridgeLowering(override val context: JvmBackendContext) :
+    FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    override fun lower(irFile: IrFile) = irFile.transformChildrenVoid(this)

    // Change calls to big arity invoke functions to vararg calls.
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/GenerateMultifileFacades.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/GenerateMultifileFacades.kt
@@ -27,10 +27,10 @@ import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.addConstructor
 import org.jetbrains.kotlin.ir.builders.declarations.buildClass
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
 import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.copyTypeArgumentsFrom
 import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
+import org.jetbrains.kotlin.ir.factories.createFile
 import org.jetbrains.kotlin.ir.types.typeWith
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
@@ -106,7 +106,7 @@ private fun generateMultifileFacades(
        }

        val fileEntry = MultifileFacadeFileEntry(jvmClassName, partClasses.map(IrClass::fileParent))
-        val file = IrFileImpl(fileEntry, EmptyPackageFragmentDescriptor(module, kotlinPackageFqName))
+        val file = context.irDeclarationFactory.createFile(fileEntry, EmptyPackageFragmentDescriptor(module, kotlinPackageFqName))

        context.log {
            "Multifile facade $jvmClassName:\n  ${partClasses.joinToString("\n  ") { it.fqNameWhenAvailable!!.asString() }}\n"
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/InlineCallableReferenceToLambda.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/InlineCallableReferenceToLambda.kt
@@ -44,8 +44,8 @@ internal val inlineCallableReferenceToLambdaPhase = makeIrFilePhase(
 //
 //      foo(::smth) -> foo { a -> smth(a) }
 //
-internal class InlineCallableReferenceToLambdaPhase(val context: JvmBackendContext) : FileLoweringPass,
-    IrElementTransformerVoidWithContext() {
+internal class InlineCallableReferenceToLambdaPhase(override val context: JvmBackendContext) : FileLoweringPass,
+    IrElementTransformerVoidWithContext(context) {

    private var inlinableReferences = mutableSetOf<IrCallableReference>()

--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/InterfaceDelegationLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/InterfaceDelegationLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -165,7 +165,9 @@ internal val interfaceDefaultCallsPhase = makeIrFilePhase(
    description = "Redirect interface calls with default arguments to DefaultImpls"
 )

-private class InterfaceDefaultCallsLowering(val context: JvmBackendContext) : IrElementTransformerVoidWithContext(), FileLoweringPass {
+private class InterfaceDefaultCallsLowering(
+    override val context: JvmBackendContext
+) : IrElementTransformerVoidWithContext(context), FileLoweringPass {
    // TODO If there are no default _implementations_ we can avoid generating defaultImpls class entirely by moving default arg dispatchers to the interface class
    override fun lower(irFile: IrFile) {
        irFile.transformChildrenVoid(this)
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmInlineClassLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmInlineClassLowering.kt
@@ -52,7 +52,9 @@ val jvmInlineClassPhase = makeIrFilePhase(
 * We do not unfold inline class types here. Instead, the type mapper will lower inline class
 * types to the types of their underlying field.
 */
-private class JvmInlineClassLowering(private val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+private class JvmInlineClassLowering(
+    override val context: JvmBackendContext
+) : FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    private val valueMap = mutableMapOf<IrValueSymbol, IrValueDeclaration>()

    override fun lower(irFile: IrFile) {
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmOverloadsAnnotationLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmOverloadsAnnotationLowering.kt
@@ -1,20 +1,18 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.common.ir.copyTo
 import org.jetbrains.kotlin.backend.common.ir.copyTypeParametersFrom
+import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.backend.jvm.JvmLoweredDeclarationOrigin
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.expressions.impl.*
@@ -120,7 +118,7 @@ private class JvmOverloadsAnnotationLowering(val context: JvmBackendContext) : C
        val res = when (oldFunction) {
            is IrConstructor -> {
                val descriptor = WrappedClassConstructorDescriptor(oldFunction.descriptor.annotations)
-                IrConstructorImpl(
+                context.irDeclarationFactory.createConstructor(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.JVM_OVERLOADS_WRAPPER,
                    IrConstructorSymbolImpl(descriptor),
@@ -137,7 +135,7 @@ private class JvmOverloadsAnnotationLowering(val context: JvmBackendContext) : C
            }
            is IrSimpleFunction -> {
                val descriptor = WrappedSimpleFunctionDescriptor(oldFunction.descriptor.annotations)
-                IrFunctionImpl(
+                context.irDeclarationFactory.createSimpleFunction(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.JVM_OVERLOADS_WRAPPER,
                    IrSimpleFunctionSymbolImpl(descriptor),
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmStaticAnnotationLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmStaticAnnotationLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -21,7 +21,6 @@ import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.descriptors.Visibility
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedFunctionDescriptorWithContainerSource
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrBody
@@ -99,7 +98,7 @@ private class CompanionObjectJvmStaticLowering(val context: JvmBackendContext) :
        val origin =
            if (isSynthetic) JvmLoweredDeclarationOrigin.JVM_STATIC_WRAPPER_SYNTHETIC else JvmLoweredDeclarationOrigin.JVM_STATIC_WRAPPER
        val descriptor = WrappedSimpleFunctionDescriptor(target.descriptor.annotations)
-        return IrFunctionImpl(
+        return context.irDeclarationFactory.createSimpleFunction(
            UNDEFINED_OFFSET, UNDEFINED_OFFSET,
            origin,
            IrSimpleFunctionSymbolImpl(descriptor),
@@ -229,7 +228,7 @@ private class MakeCallsStatic(
        val newDescriptor = (descriptor as? DescriptorWithContainerSource)?.let {
            WrappedFunctionDescriptorWithContainerSource(it.containerSource)
        } ?: WrappedSimpleFunctionDescriptor(descriptor)
-        return IrFunctionImpl(
+        return context.irDeclarationFactory.createSimpleFunction(
            startOffset, endOffset, origin,
            IrSimpleFunctionSymbolImpl(newDescriptor),
            name,
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmStringConcatenationLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmStringConcatenationLowering.kt
@@ -45,7 +45,9 @@ internal val jvmStringConcatenationLowering = makeIrFilePhase(
 * is that this pass also handles JVM specific optimizations, such as calling stringPlus
 * for two arguments, and properly handles inline classes.
 */
-private class JvmStringConcatenationLowering(val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+private class JvmStringConcatenationLowering(
+    override val context: JvmBackendContext
+) : FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    override fun lower(irFile: IrFile) = irFile.transformChildrenVoid()

    private val stringBuilder = context.ir.symbols.stringBuilder.owner
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/MoveCompanionObjectFieldsLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/MoveCompanionObjectFieldsLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -13,7 +13,6 @@ import org.jetbrains.kotlin.backend.jvm.ir.replaceThisByStaticReference
 import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.builders.declarations.addField
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrAnonymousInitializerImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
@@ -94,7 +93,7 @@ private class MoveOrCopyCompanionObjectFieldsLowering(val context: JvmBackendCon
        with(oldInitializer) {
            val oldParent = parentAsClass
            val newSymbol = IrAnonymousInitializerSymbolImpl(newParent.symbol)
-            IrAnonymousInitializerImpl(startOffset, endOffset, origin, newSymbol, isStatic = true).apply {
+            context.irDeclarationFactory.createAnonymousInitializer(startOffset, endOffset, origin, newSymbol, isStatic = true).apply {
                parent = newParent
                body = this@with.body
                    .replaceThisByStaticReference(context.declarationFactory, oldParent, oldParent.thisReceiver!!)
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/ObjectClassLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/ObjectClassLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -7,15 +7,18 @@ package org.jetbrains.kotlin.backend.jvm.lower

 import org.jetbrains.kotlin.backend.common.FileLoweringPass
 import org.jetbrains.kotlin.backend.common.IrElementTransformerVoidWithContext
-import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
+import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.builders.irCall
 import org.jetbrains.kotlin.ir.builders.irExprBody
 import org.jetbrains.kotlin.ir.builders.irGetField
-import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.util.*
+import org.jetbrains.kotlin.ir.declarations.IrClass
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationContainer
+import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.util.constructors
+import org.jetbrains.kotlin.ir.util.isObject

 internal val objectClassPhase = makeIrFilePhase(
    ::ObjectClassLowering,
@@ -23,7 +26,9 @@ internal val objectClassPhase = makeIrFilePhase(
    description = "Handle object classes"
 )

-private class ObjectClassLowering(val context: JvmBackendContext) : IrElementTransformerVoidWithContext(), FileLoweringPass {
+private class ObjectClassLowering(
+    override val context: JvmBackendContext
+) : IrElementTransformerVoidWithContext(context), FileLoweringPass {

    private var pendingTransformations = mutableListOf<Function0<Unit>>()

--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/PropertyReferenceLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/PropertyReferenceLowering.kt
@@ -165,7 +165,7 @@ internal class PropertyReferenceLowering(val context: JvmBackendContext) : Class
        }
        var localPropertiesInClass = 0

-        irClass.transformChildrenVoid(object : IrElementTransformerVoidWithContext() {
+        irClass.transformChildrenVoid(object : IrElementTransformerVoidWithContext(context) {
            override fun visitLocalDelegatedProperty(declaration: IrLocalDelegatedProperty): IrStatement {
                localPropertyIndices[declaration.getter.symbol] = localPropertiesInClass++
                return super.visitLocalDelegatedProperty(declaration)
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/RenameFieldsLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/RenameFieldsLowering.kt
@@ -14,13 +14,13 @@ import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationParent
 import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.declarations.IrFile
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedFieldDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrGetField
 import org.jetbrains.kotlin.ir.expressions.IrSetField
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrSetFieldImpl
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrFieldSymbolImpl
 import org.jetbrains.kotlin.ir.util.hasAnnotation
@@ -72,7 +72,7 @@ private class RenameFieldsLowering(val context: CommonBackendContext) : FileLowe
            }
        }

-        val renamer = FieldRenamer(newNames)
+        val renamer = FieldRenamer(newNames, context.irDeclarationFactory)
        irFile.transform(renamer, null)

        irFile.transform(FieldAccessTransformer(renamer.newSymbols), null)
@@ -94,7 +94,10 @@ private class FieldNameCollector : IrElementVisitorVoid {
    }
 }

-private class FieldRenamer(private val newNames: Map<IrField, Name>) : IrElementTransformerVoid() {
+private class FieldRenamer(
+    private val newNames: Map<IrField, Name>,
+    private val irDeclarationFactory: IrDeclarationFactory
+) : IrElementTransformerVoid() {
    val newSymbols = mutableMapOf<IrField, IrFieldSymbol>()

    override fun visitField(declaration: IrField): IrStatement {
@@ -102,7 +105,7 @@ private class FieldRenamer(private val newNames: Map<IrField, Name>) : IrElement

        val descriptor = WrappedFieldDescriptor()
        val symbol = IrFieldSymbolImpl(descriptor)
-        return IrFieldImpl(
+        return irDeclarationFactory.createField(
            declaration.startOffset, declaration.endOffset, declaration.origin, symbol, newName,
            declaration.type, declaration.visibility, declaration.isFinal, declaration.isExternal, declaration.isStatic,
            isFakeOverride = declaration.origin == IrDeclarationOrigin.FAKE_OVERRIDE
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/SingleAbstractMethodLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/SingleAbstractMethodLowering.kt
@@ -47,7 +47,7 @@ internal val singleAbstractMethodPhase = makeIrFilePhase(
    description = "Replace SAM conversions with instances of interface-implementing classes"
 )

-class SingleAbstractMethodLowering(val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+class SingleAbstractMethodLowering(context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    // SAM wrappers are cached, either in the file class (if it exists), or in a top-level enclosing class.
    // In the latter case, the names of SAM wrappers depend on the order of classes in the file. For example:
    //
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/SingletonReferencesLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/SingletonReferencesLowering.kt
@@ -1,15 +1,21 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.*
+import org.jetbrains.kotlin.backend.common.FileLoweringPass
+import org.jetbrains.kotlin.backend.common.IrElementTransformerVoidWithContext
 import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
+import org.jetbrains.kotlin.backend.common.pop
+import org.jetbrains.kotlin.backend.common.push
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.IrEnumConstructorCall
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.IrGetEnumValue
+import org.jetbrains.kotlin.ir.expressions.IrGetObjectValue
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
 import org.jetbrains.kotlin.ir.types.classOrNull
@@ -21,7 +27,9 @@ internal val singletonReferencesPhase = makeIrFilePhase(
    description = "Handle singleton references"
 )

-private class SingletonReferencesLowering(val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+private class SingletonReferencesLowering(
+    override val context: JvmBackendContext
+) : FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    private val constructingEnums = arrayListOf<IrDeclarationParent>()

    override fun lower(irFile: IrFile) {
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/SyntheticAccessorLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/SyntheticAccessorLowering.kt
@@ -26,7 +26,6 @@ import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
 import org.jetbrains.kotlin.ir.builders.declarations.buildConstructor
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
 import org.jetbrains.kotlin.ir.symbols.*
@@ -38,7 +37,9 @@ import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.utils.addToStdlib.safeAs

-internal class SyntheticAccessorLowering(val context: JvmBackendContext) : IrElementTransformerVoidWithContext(), FileLoweringPass {
+internal class SyntheticAccessorLowering(
+    override val context: JvmBackendContext
+) : IrElementTransformerVoidWithContext(context), FileLoweringPass {
    private val pendingTransformations = mutableListOf<Function0<Unit>>()
    private val inlineLambdaToCallSite = mutableMapOf<IrFunction, IrDeclaration?>()

@@ -133,7 +134,7 @@ internal class SyntheticAccessorLowering(val context: JvmBackendContext) : IrEle
            // attaching the metadata directly to the bridge. We also have to move all annotations
            // to the bridge method. Parameter annotations are already moved by the copyTo method.
            accessor.metadata = declaration.metadata
-            declaration.safeAs<IrConstructorImpl>()?.metadata = null
+            declaration.safeAs<IrConstructor>()?.metadata = null
            accessor.annotations += declaration.annotations
            declaration.annotations.clear()
            declaration.valueParameters.forEach { it.annotations.clear() }
@@ -148,7 +149,7 @@ internal class SyntheticAccessorLowering(val context: JvmBackendContext) : IrEle
            classes.lastOrNull { parent is IrClass && it.isSubclassOf(parent) } ?: classes.last()
        } else parent

-    private fun IrConstructor.makeConstructorAccessor(): IrConstructorImpl {
+    private fun IrConstructor.makeConstructorAccessor(): IrConstructor {
        val source = this

        return buildConstructor {
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/ToArrayLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/ToArrayLowering.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.
 */

@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.backend.jvm.JvmLoweredDeclarationOrigin
 import org.jetbrains.kotlin.backend.jvm.codegen.isJvmInterface
-import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
@@ -21,9 +20,6 @@ import org.jetbrains.kotlin.ir.builders.irReturn
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrTypeParameterImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedTypeParameterDescriptor
 import org.jetbrains.kotlin.ir.descriptors.WrappedValueParameterDescriptor
@@ -35,9 +31,7 @@ import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.defaultType
 import org.jetbrains.kotlin.ir.util.isClass
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
 import org.jetbrains.kotlin.types.Variance
-import org.jetbrains.kotlin.types.checker.KotlinTypeChecker
 import org.jetbrains.kotlin.utils.DFS

 internal val toArrayPhase = makeIrFilePhase(
@@ -60,7 +54,7 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow
        if (genericToArray == null) {
            if (isDirectCollectionSubClass) {
                val typeParameterDescriptor = WrappedTypeParameterDescriptor()
-                val typeParameter = IrTypeParameterImpl(
+                val typeParameter = context.irDeclarationFactory.createTypeParameter(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.TO_ARRAY,
                    IrTypeParameterSymbolImpl(typeParameterDescriptor),
@@ -75,7 +69,7 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow

                val substitutedArrayType = irBuiltIns.arrayClass.typeWith(typeParameter.defaultType)
                val functionDescriptor = WrappedSimpleFunctionDescriptor()
-                val irFunction = IrFunctionImpl(
+                val irFunction = context.irDeclarationFactory.createSimpleFunction(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.TO_ARRAY,
                    IrSimpleFunctionSymbolImpl(functionDescriptor),
@@ -98,7 +92,7 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow
                irFunction.typeParameters.add(typeParameter)

                val dispatchReceiverParameterDescriptor = WrappedValueParameterDescriptor()
-                irFunction.dispatchReceiverParameter = IrValueParameterImpl(
+                irFunction.dispatchReceiverParameter = context.irDeclarationFactory.createValueParameter(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.TO_ARRAY,
                    IrValueParameterSymbolImpl(dispatchReceiverParameterDescriptor),
@@ -113,7 +107,7 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow
                }
                val valueParameterDescriptor = WrappedValueParameterDescriptor()
                irFunction.valueParameters.add(
-                    IrValueParameterImpl(
+                    context.irDeclarationFactory.createValueParameter(
                        UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                        JvmLoweredDeclarationOrigin.TO_ARRAY,
                        IrValueParameterSymbolImpl(valueParameterDescriptor),
@@ -143,13 +137,13 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow
                irClass.declarations.add(irFunction)
            }
        } else {
-            (genericToArray as IrFunctionImpl).visibility = Visibilities.PUBLIC
+            genericToArray.visibility = Visibilities.PUBLIC
        }

        if (nonGenericToArray == null) {
            if (isDirectCollectionSubClass) {
                val functionDescriptor = WrappedSimpleFunctionDescriptor()
-                val irFunction = IrFunctionImpl(
+                val irFunction = context.irDeclarationFactory.createSimpleFunction(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.TO_ARRAY,
                    IrSimpleFunctionSymbolImpl(functionDescriptor),
@@ -169,7 +163,7 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow
            irFunction.parent = irClass

                val dispatchReceiverParameterDescriptor = WrappedValueParameterDescriptor()
-                irFunction.dispatchReceiverParameter = IrValueParameterImpl(
+                irFunction.dispatchReceiverParameter = context.irDeclarationFactory.createValueParameter(
                    UNDEFINED_OFFSET, UNDEFINED_OFFSET,
                    JvmLoweredDeclarationOrigin.TO_ARRAY,
                    IrValueParameterSymbolImpl(dispatchReceiverParameterDescriptor),
@@ -196,7 +190,7 @@ private class ToArrayLowering(private val context: JvmBackendContext) : ClassLow
                irClass.declarations.add(irFunction)
            }
        } else {
-            (nonGenericToArray as IrFunctionImpl).visibility = Visibilities.PUBLIC
+            nonGenericToArray.visibility = Visibilities.PUBLIC
        }
    }
 }
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/VarargLowering.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/VarargLowering.kt
@@ -33,7 +33,7 @@ val varargPhase = makeIrFilePhase(
    prerequisite = setOf(polymorphicSignaturePhase)
 )

-private class VarargLowering(val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext() {
+private class VarargLowering(override val context: JvmBackendContext) : FileLoweringPass, IrElementTransformerVoidWithContext(context) {
    override fun lower(irFile: IrFile) = irFile.transformChildrenVoid()

    // Ignore annotations
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/inlineclasses/MemoizedInlineClassReplacements.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/inlineclasses/MemoizedInlineClassReplacements.kt
@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.builders.declarations.buildFunWithDescriptorForInlining
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrValueParameterSymbol
@@ -189,7 +188,7 @@ class MemoizedInlineClassReplacements {
        return IrReplacementFunction(replacement, parameterMap)
    }

-    private fun buildReplacement(function: IrFunction, body: IrFunctionImpl.() -> Unit) =
+    private fun buildReplacement(function: IrFunction, body: IrSimpleFunction.() -> Unit) =
        buildFunWithDescriptorForInlining(function.descriptor) {
            updateFrom(function)
            if (function.origin == IrDeclarationOrigin.GENERATED_INLINE_CLASS_MEMBER) {
--- a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmBackendContext.kt
+++ b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmBackendContext.kt
@@ -16,12 +16,13 @@ import org.jetbrains.kotlin.descriptors.impl.EmptyPackageFragmentDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.backend.js.JsSharedVariablesManager
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.createExternalPackageFragment
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.ir.symbols.IrExternalPackageFragmentSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
-import org.jetbrains.kotlin.ir.symbols.IrExternalPackageFragmentSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
 import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.ir.util.UniqId
@@ -31,6 +32,7 @@ class WasmBackendContext(
    val module: ModuleDescriptor,
    override val irBuiltIns: IrBuiltIns,
    symbolTable: SymbolTable,
+    override val irDeclarationFactory: IrDeclarationFactory,
    irModuleFragment: IrModuleFragment,
    val additionalExportedDeclarations: Set<FqName>,
    override val configuration: CompilerConfiguration
@@ -43,24 +45,24 @@ class WasmBackendContext(

    // Place to store declarations excluded from code generation
    val excludedDeclarations: IrPackageFragment by lazy {
-        IrExternalPackageFragmentImpl(
+        irDeclarationFactory.createExternalPackageFragment(
            DescriptorlessExternalPackageFragmentSymbol(),
            FqName("kotlin")
        )
    }

-    override val declarationFactory = JsDeclarationFactory()
+    override val declarationFactory = JsDeclarationFactory(irDeclarationFactory)

    val objectToGetInstanceFunction = mutableMapOf<IrClassSymbol, IrSimpleFunction>()
    override val internalPackageFqn = FqName("kotlin.wasm")

-    private val internalPackageFragment = IrExternalPackageFragmentImpl(
+    private val internalPackageFragment = irDeclarationFactory.createExternalPackageFragment(
        IrExternalPackageFragmentSymbolImpl(
            EmptyPackageFragmentDescriptor(builtIns.builtInsModule, FqName("kotlin.wasm.internal"))
        )
    )

-    override val sharedVariablesManager = JsSharedVariablesManager(irBuiltIns, internalPackageFragment)
+    override val sharedVariablesManager = JsSharedVariablesManager(irBuiltIns, irDeclarationFactory, internalPackageFragment)

    val wasmSymbols: WasmSymbols = WasmSymbols(this@WasmBackendContext, symbolTable)
    override val ir = object : Ir<WasmBackendContext>(this, irModuleFragment) {
--- a/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/compiler.kt
+++ b/compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/compiler.kt
@@ -11,6 +11,7 @@ import org.jetbrains.kotlin.backend.common.phaser.invokeToplevel
 import org.jetbrains.kotlin.backend.wasm.codegen.IrModuleToWasm
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.ir.backend.js.loadIr
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.util.ExternalDependenciesGenerator
 import org.jetbrains.kotlin.ir.util.generateTypicalIrProviderList
 import org.jetbrains.kotlin.ir.util.patchDeclarationParents
@@ -26,15 +27,16 @@ fun compileWasm(
    files: List<KtFile>,
    configuration: CompilerConfiguration,
    phaseConfig: PhaseConfig,
+    irDeclarationFactory: IrDeclarationFactory,
    allDependencies: KotlinLibraryResolveResult,
    friendDependencies: List<KotlinLibrary>,
    exportedDeclarations: Set<FqName> = emptySet()
 ): WasmCompilerResult {
    val (moduleFragment, dependencyModules, irBuiltIns, symbolTable, deserializer) =
-        loadIr(project, files, configuration, allDependencies, friendDependencies)
+        loadIr(project, files, configuration, irDeclarationFactory, allDependencies, friendDependencies)

    val moduleDescriptor = moduleFragment.descriptor
-    val context = WasmBackendContext(moduleDescriptor, irBuiltIns, symbolTable, moduleFragment, exportedDeclarations, configuration)
+    val context = WasmBackendContext(moduleDescriptor, irBuiltIns, symbolTable, irDeclarationFactory, moduleFragment, exportedDeclarations, configuration)

    // Load declarations referenced during `context` initialization
    dependencyModules.forEach {
--- a/compiler/ir/ir.psi2ir/build.gradle.kts
+++ b/compiler/ir/ir.psi2ir/build.gradle.kts
@@ -8,6 +8,7 @@ dependencies {
    compile(project(":compiler:frontend"))
    compile(project(":compiler:backend-common"))
    compile(project(":compiler:ir.tree"))
+    implementation(project(":compiler:ir.tree.impl"))
    compileOnly(intellijCoreDep()) { includeJars("intellij-core") }
 }

--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/Psi2IrTranslator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/Psi2IrTranslator.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir
@@ -21,6 +10,8 @@ import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.factories.DefaultIrDeclarationFactory
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
@@ -49,7 +40,11 @@ class Psi2IrTranslator(
        bindingContext: BindingContext,
        generatorExtensions: GeneratorExtensions
    ): IrModuleFragment {
-        val context = createGeneratorContext(moduleDescriptor, bindingContext, extensions = generatorExtensions)
+        val context = createGeneratorContext(
+            moduleDescriptor, bindingContext,
+            extensions = generatorExtensions,
+            irDeclarationFactory = DefaultIrDeclarationFactory() ///
+        )
        val irProviders = generateTypicalIrProviderList(
            moduleDescriptor, context.irBuiltIns, context.symbolTable, extensions = generatorExtensions
        )
@@ -59,10 +54,12 @@ class Psi2IrTranslator(
    fun createGeneratorContext(
        moduleDescriptor: ModuleDescriptor,
        bindingContext: BindingContext,
-        symbolTable: SymbolTable = SymbolTable(mangler),
+        irDeclarationFactory: IrDeclarationFactory,
+        symbolTable: SymbolTable = SymbolTable(irDeclarationFactory, mangler),
        extensions: GeneratorExtensions = GeneratorExtensions()
    ): GeneratorContext =
-        GeneratorContext(configuration, moduleDescriptor, bindingContext, languageVersionSettings, symbolTable, extensions)
+        GeneratorContext(configuration, moduleDescriptor, bindingContext,
+                         languageVersionSettings, symbolTable, irDeclarationFactory, extensions)

    fun generateModuleFragment(
        context: GeneratorContext,
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/BodyGenerator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/BodyGenerator.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir.generators
@@ -48,7 +37,7 @@ class BodyGenerator(
    private val typeTranslator = context.typeTranslator
    private fun KotlinType.toIrType() = typeTranslator.translateType(this)

-    override val scope = Scope(scopeOwnerSymbol)
+    override val scope = Scope(scopeOwnerSymbol, context.irDeclarationFactory)
    private val loopTable = HashMap<KtLoopExpression, IrLoop>()

    fun generateFunctionBody(ktBody: KtExpression): IrBody {
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/DataClassMembersGenerator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/DataClassMembersGenerator.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir.generators
@@ -69,7 +58,7 @@ class DataClassMembersGenerator(
        startOffset: Int = UNDEFINED_OFFSET,
        endOffset: Int = UNDEFINED_OFFSET,
        val irFunction: IrFunction = declareSimpleFunction(startOffset, endOffset, origin, function)
-    ) : IrBlockBodyBuilder(context, Scope(irFunction.symbol), startOffset, endOffset) {
+    ) : IrBlockBodyBuilder(context, Scope(irFunction.symbol, context.irDeclarationFactory), startOffset, endOffset) {
        inline fun addToClass(builder: MemberFunctionBuilder.(IrFunction) -> Unit): IrFunction {
            irFunction.buildWithScope {
                builder(irFunction)
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/DeclarationGenerator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/DeclarationGenerator.kt
@@ -1,26 +1,17 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir.generators

-import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
+import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrErrorDeclarationImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrTypeAliasImpl
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
+import org.jetbrains.kotlin.ir.factories.createTypeAlias
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.util.withScope
 import org.jetbrains.kotlin.psi.*
@@ -51,7 +42,7 @@ class DeclarationGenerator(override val context: GeneratorContext) : Generator {
            is KtScript ->
                ScriptGenerator(this).generateScriptDeclaration(ktDeclaration)
            else ->
-                IrErrorDeclarationImpl(
+                context.irDeclarationFactory.createErrorDeclaration(
                    ktDeclaration.startOffsetSkippingComments, ktDeclaration.endOffset,
                    getOrFail(BindingContext.DECLARATION_TO_DESCRIPTOR, ktDeclaration)
                )
@@ -82,7 +73,7 @@ class DeclarationGenerator(override val context: GeneratorContext) : Generator {
    private fun generateTypeAliasDeclaration(ktTypeAlias: KtTypeAlias): IrTypeAlias {
        val typeAliasDescriptor = getOrFail(BindingContext.TYPE_ALIAS, ktTypeAlias)
        val irTypeAlias = context.symbolTable.declareTypeAlias(typeAliasDescriptor) { symbol ->
-            IrTypeAliasImpl.fromSymbolDescriptor(
+            context.irDeclarationFactory.createTypeAlias(
                ktTypeAlias.startOffsetSkippingComments, ktTypeAlias.endOffset,
                symbol,
                typeAliasDescriptor.expandedType.toIrType(),
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/DelegatedPropertyGenerator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/DelegatedPropertyGenerator.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir.generators
@@ -22,7 +11,6 @@ import org.jetbrains.kotlin.ir.builders.irBlockBody
 import org.jetbrains.kotlin.ir.builders.irGet
 import org.jetbrains.kotlin.ir.builders.irReturn
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
 import org.jetbrains.kotlin.ir.descriptors.IrLocalDelegatedPropertyDelegateDescriptor
 import org.jetbrains.kotlin.ir.descriptors.IrLocalDelegatedPropertyDelegateDescriptorImpl
 import org.jetbrains.kotlin.ir.descriptors.IrPropertyDelegateDescriptor
@@ -30,6 +18,7 @@ import org.jetbrains.kotlin.ir.descriptors.IrPropertyDelegateDescriptorImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
+import org.jetbrains.kotlin.ir.factories.createField
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.symbols.IrVariableSymbol
@@ -130,7 +119,7 @@ class DelegatedPropertyGenerator(declarationGenerator: DeclarationGenerator) : D
        return context.symbolTable.declareField(
            startOffset, endOffset, origin, delegateDescriptor, type
        ) {
-            IrFieldImpl(startOffset, endOffset, origin, it, type).apply {
+            context.irDeclarationFactory.createField(startOffset, endOffset, origin, it, type).apply {
                metadata = MetadataSource.Property(propertyDescriptor)
            }
        }.also { irDelegate ->
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/GeneratorContext.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/GeneratorContext.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir.generators
@@ -24,6 +13,7 @@ import org.jetbrains.kotlin.descriptors.NotFoundClasses
 import org.jetbrains.kotlin.ir.builders.IrGeneratorContext
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.expressions.IrMemberAccessExpression
+import org.jetbrains.kotlin.ir.factories.IrDeclarationFactory
 import org.jetbrains.kotlin.ir.util.ConstantValueGenerator
 import org.jetbrains.kotlin.ir.util.SymbolTable
 import org.jetbrains.kotlin.ir.util.TypeTranslator
@@ -38,6 +28,7 @@ class GeneratorContext(
    val bindingContext: BindingContext,
    val languageVersionSettings: LanguageVersionSettings,
    val symbolTable: SymbolTable,
+    val irDeclarationFactory: IrDeclarationFactory,
    val extensions: GeneratorExtensions
 ) : IrGeneratorContext() {

@@ -50,7 +41,7 @@ class GeneratorContext(
        constantValueGenerator.typeTranslator = typeTranslator
    }

-    override val irBuiltIns: IrBuiltIns = IrBuiltIns(moduleDescriptor.builtIns, typeTranslator, symbolTable)
+    override val irBuiltIns: IrBuiltIns = IrBuiltIns(moduleDescriptor.builtIns, typeTranslator, irDeclarationFactory, symbolTable)

    val sourceManager = PsiSourceManager()

--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ModuleGenerator.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/ModuleGenerator.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.psi2ir.generators
@@ -20,8 +9,7 @@ import org.jetbrains.kotlin.backend.common.CodegenUtil
 import org.jetbrains.kotlin.ir.declarations.IrFile
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
 import org.jetbrains.kotlin.ir.declarations.MetadataSource
-import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrModuleFragmentImpl
+import org.jetbrains.kotlin.ir.factories.createFile
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.resolve.BindingContext
@@ -38,7 +26,7 @@ class ModuleGenerator(override val context: GeneratorContext) : Generator {
        }

    fun generateModuleFragmentWithoutDependencies(ktFiles: Collection<KtFile>): IrModuleFragment =
-        IrModuleFragmentImpl(context.moduleDescriptor, context.irBuiltIns).also { irModule ->
+        context.irDeclarationFactory.createModuleFragment(context.moduleDescriptor, context.irBuiltIns).also { irModule ->
            irModule.files.addAll(generateFiles(ktFiles))
        }

@@ -66,7 +54,7 @@ class ModuleGenerator(override val context: GeneratorContext) : Generator {
        }
    }

-    private fun generateSingleFile(irDeclarationGenerator: DeclarationGenerator, ktFile: KtFile): IrFileImpl {
+    private fun generateSingleFile(irDeclarationGenerator: DeclarationGenerator, ktFile: KtFile): IrFile {
        val irFile = createEmptyIrFile(ktFile)

        for (ktAnnotationEntry in ktFile.annotationEntries) {
@@ -81,10 +69,10 @@ class ModuleGenerator(override val context: GeneratorContext) : Generator {
        return irFile
    }

-    private fun createEmptyIrFile(ktFile: KtFile): IrFileImpl {
+    private fun createEmptyIrFile(ktFile: KtFile): IrFile {
        val fileEntry = context.sourceManager.getOrCreateFileEntry(ktFile)
        val packageFragmentDescriptor = context.moduleDescriptor.findPackageFragmentForFile(ktFile)!!
-        val irFile = IrFileImpl(fileEntry, packageFragmentDescriptor).apply {
+        val irFile = context.irDeclarationFactory.createFile(fileEntry, packageFragmentDescriptor).apply {
            metadata = MetadataSource.File(CodegenUtil.getMemberDescriptorsToGenerate(ktFile, context.bindingContext))
        }
        context.sourceManager.putFileEntry(irFile, fileEntry)
--- a/compiler/ir/ir.tree.impl/build.gradle.kts
+++ b/compiler/ir/ir.tree.impl/build.gradle.kts
@@ -0,0 +1,18 @@
+
+plugins {
+    kotlin("jvm")
+    id("jps-compatible")
+}
+
+dependencies {
+//    compile(project(":compiler:util"))
+//    compile(project(":compiler:frontend"))
+    compile(project(":compiler:ir.tree"))
+//    compileOnly(intellijCoreDep()) { includeJars("intellij-core") }
+}
+
+sourceSets {
+    "main" { projectDefault() }
+    "test" {}
+}
+
--- a/compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrAnonymousInitializerImpl.kt
+++ b/compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrAnonymousInitializerImpl.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.ir.declarations.impl
--- a/compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrClassImpl.kt
+++ b/compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrClassImpl.kt
@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+ * 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.ir.declarations.impl
@@ -27,7 +16,6 @@ import org.jetbrains.kotlin.ir.util.transform
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.resolve.descriptorUtil.isEffectivelyExternal
 import org.jetbrains.kotlin.utils.SmartList

 class IrClassImpl(
@@ -49,26 +37,6 @@ class IrClassImpl(
    IrDeclarationBase(startOffset, endOffset, origin),
    IrClass {

-    constructor(
-        startOffset: Int,
-        endOffset: Int,
-        origin: IrDeclarationOrigin,
-        symbol: IrClassSymbol,
-        modality: Modality = symbol.descriptor.modality
-    ) :
-            this(
-                startOffset, endOffset, origin, symbol,
-                symbol.descriptor.name, symbol.descriptor.kind,
-                symbol.descriptor.visibility,
-                modality = modality,
-                isCompanion = symbol.descriptor.isCompanionObject,
-                isInner = symbol.descriptor.isInner,
-                isData = symbol.descriptor.isData,
-                isExternal = symbol.descriptor.isEffectivelyExternal(),
-                isInline = symbol.descriptor.isInline,
-                isExpect = symbol.descriptor.isExpect
-            )
-
    init {
        symbol.bind(this)
    }
--- a/compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrConstructorImpl.kt
+++ b/compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrConstructorImpl.kt
@@ -0,0 +1,46 @@
+/*
+ * 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.ir.declarations.impl
+
+import org.jetbrains.kotlin.descriptors.ClassConstructorDescriptor
+import org.jetbrains.kotlin.descriptors.Visibility
+import org.jetbrains.kotlin.ir.declarations.IrConstructor
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
+import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
+import org.jetbrains.kotlin.name.Name
+
+class IrConstructorImpl(
+    startOffset: Int,
+    endOffset: Int,
+    origin: IrDeclarationOrigin,
+    override val symbol: IrConstructorSymbol,
+    name: Name,
+    visibility: Visibility,
+    returnType: IrType,
+    isInline: Boolean,
+    isExternal: Boolean,
+    override val isPrimary: Boolean,
+    isExpect: Boolean
+) :
+    IrFunctionBase(
+        startOffset, endOffset, origin, name,
+        visibility,
+        isInline, isExternal, isExpect,
+        returnType
+    ),
+    IrConstructor {
+
+    init {
+        symbol.bind(this)
+    }
+
+    override val descriptor: ClassConstructorDescriptor get() = symbol.descriptor
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitConstructor(this, data)
+}
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Zalim Bashorov	f1d95256d1	~ jvm-cli: reset ir factory if an exception was thrown	2019-12-26 05:27:21 +03:00
Zalim Bashorov	0835074e0a	~ fix BasicWasmBoxTest.kt	2019-12-26 05:26:16 +03:00
Zalim Bashorov	e01726a81a	~ fix build of kotlin-scripting-js-test	2019-12-26 05:25:47 +03:00
Zalim Bashorov	5169cb6d94	~ cli-js-klib (part of ir.serialization.js before): fix after rebase	2019-12-26 02:48:33 +03:00
Zalim Bashorov	cd6cc33263	~ ir.serialization.js: fix after rebase	2019-12-26 02:45:55 +03:00
Zalim Bashorov	3eb3e9e9f8	~ ir.serialization.js: fix after rebase	2019-12-26 02:39:06 +03:00
Zalim Bashorov	997dbd6125	~ backend.jvm: fixes after rebase	2019-12-26 02:38:19 +03:00
Zalim Bashorov	b98f2a261d	~ cli-js use IrDeclarationFactory.resetDefaultIrDeclarationFactory	2019-12-26 02:16:32 +03:00
Zalim Bashorov	078ab5d55e	~ js.tests use IrDeclarationFactory.resetDefaultIrDeclarationFactory	2019-12-26 02:16:32 +03:00
Zalim Bashorov	0cdb7122ee	~ add IrDeclarationFactory.resetDefaultIrDeclarationFactory	2019-12-26 02:16:32 +03:00
Zalim Bashorov	763cd8c202	~ fix ir.serialization.js	2019-12-26 02:16:31 +03:00
Zalim Bashorov	490ec2b56d	~ backend.wasm	2019-12-26 02:16:13 +03:00
Zalim Bashorov	0cee28869f	~ backend.common for kotlinx-serialization	2019-12-26 02:16:13 +03:00
Zalim Bashorov	07b27856b0	~ tests-common	2019-12-26 02:16:12 +03:00
Zalim Bashorov	2b9de1bcf2	~ ir.tree	2019-12-26 02:16:12 +03:00
Zalim Bashorov	f3883c3954	~ kotlin-scripting-compiler	2019-12-26 02:16:12 +03:00
Zalim Bashorov	eace22c5c6	~ HACK ir.serialization.js for kotlinx-serialization	2019-12-26 02:16:12 +03:00
Zalim Bashorov	f749f04f3c	~ kotlinx-serialization	2019-12-26 02:16:12 +03:00
Zalim Bashorov	749f19c948	~ backend.jvm for kotlinx-serialization	2019-12-26 02:16:12 +03:00
Zalim Bashorov	297bbb570f	~ cli.js	2019-12-26 02:16:12 +03:00
Zalim Bashorov	2cddbc0e24	~ js.tests	2019-12-26 02:16:11 +03:00
Zalim Bashorov	339ea318f7	~ backend.wasm	2019-12-26 02:16:10 +03:00
Zalim Bashorov	871d254ecf	~ backend.js successfully compiled	2019-12-26 02:16:10 +03:00
Zalim Bashorov	eed1a49adb	~ serialization.common for backend.js	2019-12-26 02:16:10 +03:00
Zalim Bashorov	d5a35e0969	~ serialization.js for backend.js	2019-12-26 02:16:10 +03:00
Zalim Bashorov	f880306142	~ idea-jvm	2019-12-26 02:16:10 +03:00
Zalim Bashorov	8fb6839bb5	~ mark HACK in psi2ir	2019-12-26 02:16:09 +03:00
Zalim Bashorov	5c32300c0e	~ fir2ir	2019-12-26 02:16:09 +03:00
Zalim Bashorov	2382320961	~ compiler.cli	2019-12-26 02:16:09 +03:00
Zalim Bashorov	3d56dbc64a	~ backend.jvm successfully compiled	2019-12-26 02:16:09 +03:00
Zalim Bashorov	9668743e5e	~ backend.common for backend.jvm	2019-12-26 02:15:25 +03:00
Zalim Bashorov	e0f569943d	~ DefaultIrDeclarationFactory.createAndRegister	2019-12-26 02:15:25 +03:00
Zalim Bashorov	fc6ef0cb88	~ ir.tree for backend.jvm	2019-12-26 02:15:25 +03:00
Zalim Bashorov	3ecf74d40d	~ tests-common	2019-12-26 02:15:24 +03:00
Zalim Bashorov	cc4231a1d4	~ ir.tree for backend.js	2019-12-26 02:15:24 +03:00
Zalim Bashorov	30526d6310	~ ir.backend.common successfully compiled	2019-12-26 02:15:23 +03:00
Zalim Bashorov	c0b104f916	~ for backend.common	2019-12-26 02:15:22 +03:00
Zalim Bashorov	358343a9ee	~ DefaultIrDeclarationFactory	2019-12-26 02:15:22 +03:00
Zalim Bashorov	d479ba3b7a	~ ir.psi2ir successfully compiled	2019-12-26 02:15:22 +03:00
Zalim Bashorov	c506f800bf	~ for ir.psi2ir	2019-12-26 02:15:22 +03:00
Zalim Bashorov	45e1268d2e	~ for ir.psi2ir	2019-12-26 02:15:21 +03:00
Zalim Bashorov	2935535471	~ ir.tree successfully compiled	2019-12-26 02:15:21 +03:00
Zalim Bashorov	3b421ecf7c	~ extract secondary constructors from IR impls and fix kotlinx.serialization	2019-12-26 02:14:55 +03:00
Zalim Bashorov	45f73b1eff	~ ir.tree.impl deps	2019-12-26 02:11:46 +03:00
Zalim Bashorov	e147d3c997	~ create ir.tree.impl	2019-12-26 02:11:46 +03:00