[JS IR BE] Move IrSerializer from native to JS

* Fix issues
2019-01-29 18:18:00 +03:00
parent 5384f23f30
commit 3a444cd0f3
38 changed files with 62204 additions and 125 deletions
@@ -583,7 +583,7 @@ open class WrappedClassDescriptor(
    private val _typeConstructor: TypeConstructor by lazy {
        LazyTypeConstructor(
            this,
-            { emptyList() },
+            { declaredTypeParameters },
            { owner.superTypes.map { it.toKotlinType() } },
            LockBasedStorageManager.NO_LOCKS
        )
@@ -36,6 +36,7 @@ import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.expressions.IrFunctionReference
+import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrBlockBodyImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrDelegatingConstructorCallImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
@@ -386,6 +387,8 @@ fun IrClass.createImplicitParameterDeclarationWithWrappedDescriptor() {
    assert(descriptor.declaredTypeParameters.isEmpty())
 }

+fun isElseBranch(branch: IrBranch) = branch is IrElseBranch || ((branch.condition as? IrConst<Boolean>)?.value == true)
+
 fun IrSimpleFunction.isMethodOfAny() =
    ((valueParameters.size == 0 && name.asString().let { it == "hashCode" || it == "toString" }) ||
            (valueParameters.size == 1 && name.asString() == "equals" && valueParameters[0].type.isNullableAny()))
@@ -34,6 +34,7 @@ import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.types.IrSimpleType
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.classifierOrFail
+import org.jetbrains.kotlin.ir.types.isAny
 import org.jetbrains.kotlin.ir.util.defaultType
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
@@ -209,7 +210,9 @@ fun IrConstructor.callsSuper(irBuiltIns: IrBuiltIns): Boolean {
            assert(++numberOfCalls == 1) { "More than one delegating constructor call: ${symbol.owner}" }
            val delegatingClass = expression.symbol.owner.parent as IrClass
            // TODO: figure out why Lazy IR multiplies Declarations for descriptors and fix it
-            if (delegatingClass.descriptor == superClass.classifierOrFail.descriptor)
+            if (delegatingClass.descriptor == superClass.classifierOrFail.descriptor || (
+                        delegatingClass.defaultType.isAny() && superClass.isAny()
+                        ))
                callsSuper = true
            else if (delegatingClass.descriptor != constructedClass.descriptor)
                throw AssertionError(
@@ -6,42 +6,42 @@
 package org.jetbrains.kotlin.ir.backend.js

 import com.intellij.openapi.project.Project
-import com.intellij.openapi.util.io.FileUtil
-import com.intellij.openapi.vfs.VfsUtilCore
 import org.jetbrains.kotlin.backend.common.CompilerPhaseManager
-import org.jetbrains.kotlin.backend.common.output.OutputFile
-import org.jetbrains.kotlin.backend.common.output.OutputFileCollection
-import org.jetbrains.kotlin.backend.common.output.SimpleOutputBinaryFile
-import org.jetbrains.kotlin.backend.common.output.SimpleOutputFileCollection
+import org.jetbrains.kotlin.backend.common.LoggingContext
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.builtins.functions.functionInterfacePackageFragmentProvider
 import org.jetbrains.kotlin.config.CommonConfigurationKeys
 import org.jetbrains.kotlin.backend.common.phaser.invokeToplevel
 import org.jetbrains.kotlin.config.CommonConfigurationKeys
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.config.languageVersionSettings
+import org.jetbrains.kotlin.descriptors.ModuleDescriptor
+import org.jetbrains.kotlin.descriptors.impl.CompositePackageFragmentProvider
 import org.jetbrains.kotlin.descriptors.impl.ModuleDescriptorImpl
 import org.jetbrains.kotlin.incremental.components.LookupTracker
+import org.jetbrains.kotlin.ir.backend.js.lower.inline.replaceUnboundSymbols
+import org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir.*
 import org.jetbrains.kotlin.ir.backend.js.lower.serialization.metadata.*
 import org.jetbrains.kotlin.ir.backend.js.lower.coroutines.CoroutineIntrinsicLowering
 import org.jetbrains.kotlin.ir.backend.js.transformers.irToJs.IrModuleToJsTransformer
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.util.ConstantValueGenerator
 import org.jetbrains.kotlin.ir.util.SymbolTable
+import org.jetbrains.kotlin.ir.util.TypeTranslator
 import org.jetbrains.kotlin.ir.util.deepCopyWithSymbols
 import org.jetbrains.kotlin.js.analyze.TopDownAnalyzerFacadeForJS
-import org.jetbrains.kotlin.js.resolve.JsPlatform
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.progress.ProgressIndicatorAndCompilationCanceledStatus
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi2ir.Psi2IrTranslator
-import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.CompilerDeserializationConfiguration
-import org.jetbrains.kotlin.serialization.js.JsSerializerProtocol
 import org.jetbrains.kotlin.storage.LockBasedStorageManager
-import org.jetbrains.kotlin.utils.JsMetadataVersion
-import org.jetbrains.kotlin.utils.KotlinJavascriptMetadataUtils
 import java.io.File
 import org.jetbrains.kotlin.utils.DFS

+data class Result(val moduleDescriptor: ModuleDescriptor, val generatedCode: String, val moduleFragment: IrModuleFragment?)
 enum class ModuleType {
    TEST_RUNTIME,
    SECONDARY,
@@ -59,13 +59,6 @@ class CompiledModule(
        get() = moduleFragment!!.descriptor as ModuleDescriptorImpl
 }

-fun OutputFileCollection.writeAll(outputDir: File) {
-    for (file in asList()) {
-        val output = File(outputDir, file.relativePath)
-        FileUtil.writeToFile(output, file.asByteArray())
-    }
-}
-
 fun compile(
    project: Project,
    files: List<KtFile>,
@@ -92,7 +85,7 @@ fun compile(
    TopDownAnalyzerFacadeForJS.checkForErrors(files, analysisResult.bindingContext)

    val symbolTable = SymbolTable()
-    dependencies.forEach { symbolTable.loadModule(it.moduleFragment!!) }
+//    irDependencyModules.forEach { symbolTable.loadModule(it) }

    val psi2IrTranslator = Psi2IrTranslator(configuration.languageVersionSettings)
    val psi2IrContext = psi2IrTranslator.createGeneratorContext(analysisResult.moduleDescriptor, analysisResult.bindingContext, symbolTable)
@@ -111,82 +104,103 @@ fun compile(


    if (isKlibCompilation) {
-//        val declarationTable = DeclarationTable(moduleFragment.irBuiltins, DescriptorTable())
-//        val serializedIr = IrModuleSerializer(context, declarationTable/*, onlyForInlines = false*/).serializedIrModule(moduleFragment)
-//        val serializer = KonanSerializationUtil(context, configuration.get(CommonConfigurationKeys.METADATA_VERSION)!!, declarationTable)
-//        val serializedData = serializer.serializeModule(analysisResult.moduleDescriptor, serializedIr)
-//        buildLibrary(serializedData)
-//
+        val logggg = object : LoggingContext {
+            override fun log(message: () -> String) {}
+        }

-//        val declarationTable = DeclarationTable(moduleFragment.irBuiltins, DescriptorTable())
-//        val serializedIr = IrModuleSerializer(context, declarationTable/*, onlyForInlines = false*/).serializedIrModule(moduleFragment)
+        val declarationTable = DeclarationTable(moduleFragment.irBuiltins, DescriptorTable(), psi2IrContext.symbolTable)
+
+        val serializedIr = IrModuleSerializer(logggg, declarationTable/*, onlyForInlines = false*/).serializedIrModule(moduleFragment)
        val serializer = JsKlibMetadataSerializationUtil
-//        val serializedData = serializer.serializeModule(analysisResult.moduleDescriptor, serializedIr)
+
        val moduleName = configuration.get(CommonConfigurationKeys.MODULE_NAME) as String
        val metadataVersion = configuration.get(CommonConfigurationKeys.METADATA_VERSION)  as? JsKlibMetadataVersion
            ?: JsKlibMetadataVersion.INSTANCE
        val moduleDescription =
            JsKlibMetadataModuleDescriptor(moduleName, dependencies.map { it.name.asString() }, moduleFragment.descriptor)
-        var index = 0L
        val serializedData = serializer.serializeMetadata(
            psi2IrContext.bindingContext,
            moduleDescription,
            configuration.get(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS)!!,
            metadataVersion
-        ) {
-//            val index = declarationTable.descriptorTable.get(it)
-//            index?.let { newDescriptorUniqId(it) }
-            JsKlibMetadataProtoBuf.DescriptorUniqId.newBuilder().setIndex(index++).build()
-
+        ) { declarationDescriptor ->
+            val index = declarationTable.descriptorTable.get(declarationDescriptor)
+            index?.let { newDescriptorUniqId(it) }
        }
-//        buildLibrary(serializedData)
-//

        val stdKlibDir = File("js/js.translator/testData/out/klibs/runtime/").also {
            it.deleteRecursively()
            it.mkdirs()
        }
-//
-//        val moduleFile = File(stdKlibDir, "module.kji")
-//        moduleFile.writeBytes(serializedIr.module)
-//
-//        for ((id, data) in serializedIr.declarations) {
-//            val file = File(stdKlibDir, "${id.index}${if (id.isLocal) "L" else "G"}.kjd")
-//            file.writeBytes(data)
-//        }
-//
-//
-//        val debugFile = File(stdKlibDir, "debug.txt")
-//
-//        for ((id, data) in serializedIr.debugIndex) {
-//            debugFile.appendText(id.toString())
-//            debugFile.appendText(" --- ")
-//            debugFile.appendText(data)
-//            debugFile.appendText("\n")
-//        }

-        val metadata = File(stdKlibDir, "${moduleDescription.name}${JsKlibMetadataSerializationUtil.CLASS_METADATA_FILE_EXTENSION}").also {
+        val moduleFile = File(stdKlibDir, "module.kji")
+        moduleFile.writeBytes(serializedIr.module)
+
+        val irDeclarationDir = File(stdKlibDir, "ir/").also { it.mkdir() }
+
+        for ((id, data) in serializedIr.declarations) {
+            val file = File(irDeclarationDir, id.declarationFileName)
+            file.writeBytes(data)
+        }
+
+
+        val debugFile = File(stdKlibDir, "debug.txt")
+
+        for ((id, data) in serializedIr.debugIndex) {
+            debugFile.appendText(id.toString())
+            debugFile.appendText(" --- ")
+            debugFile.appendText(data)
+            debugFile.appendText("\n")
+        }
+
+        val metadata = File(stdKlibDir, "${moduleDescription.name}.${JsKlibMetadataSerializationUtil.CLASS_METADATA_FILE_EXTENSION}").also {
            it.writeBytes(serializedData.asByteArray())
        }

        val storageManager = LockBasedStorageManager("JsConfig")
-//        // CREATE NEW MODULE DESCRIPTOR HERE AND DESERIALIZE IT
-
        val lookupTracker = configuration.get(CommonConfigurationKeys.LOOKUP_TRACKER, LookupTracker.DO_NOTHING)
        val parts = serializer.readModuleAsProto(metadata.readBytes())
-        val md = ModuleDescriptorImpl(
-            Name.special("<$moduleName>"), storageManager, JsPlatform.builtIns
-        )
-        val provider = createJsKlibMetadataPackageFragmentProvider(
-            storageManager, md, parts.header, parts.body, metadataVersion,
-            CompilerDeserializationConfiguration(configuration.languageVersionSettings),
-            lookupTracker
+        val builtIns = object : KotlinBuiltIns(storageManager) {}//analysisResult.moduleDescriptor.builtIns
+        val md = ModuleDescriptorImpl(Name.special("<$moduleName>"), storageManager, builtIns)
+        builtIns.builtInsModule = md
+        val packageProviders = listOf(
+            functionInterfacePackageFragmentProvider(storageManager, md),
+            createJsKlibMetadataPackageFragmentProvider(
+                storageManager, md, parts.header, parts.body, metadataVersion,
+                CompilerDeserializationConfiguration(configuration.languageVersionSettings),
+                lookupTracker
+            )
        )

-        md.initialize(provider)
-        md.setDependencies(listOf(md, md.builtIns.builtInsModule))
+        md.initialize(CompositePackageFragmentProvider(packageProviders))
+        md.setDependencies(listOf(md/*, builtIns.builtInsModule*/))

-        TODO("Implemenet IrSerialization")
+
+        val st = SymbolTable()
+
+        val typeTranslator = TypeTranslator(st, configuration.languageVersionSettings).also {
+            it.constantValueGenerator = ConstantValueGenerator(md, st)
+        }
+
+        val irBuiltIns = IrBuiltIns(md.builtIns, typeTranslator, st)
+
+        val deserializer = IrKlibProtoBufModuleDeserializer(
+            md,
+            logggg,
+            irBuiltIns,
+            stdKlibDir,
+            st,
+            null
+        )
+        val deserializedModuleFragment = deserializer.deserializeIrModule(md, moduleFile.readBytes(), true)
+
+        val context = JsIrBackendContext(md, irBuiltIns, st, deserializedModuleFragment, configuration, irDependencyModules)
+
+        deserializedModuleFragment.replaceUnboundSymbols(context)
+
+        jsPhases.invokeToplevel(context.phaseConfig, context, moduleFragment)
+
+        return Result(md, context.jsProgram.toString(), null)
    } else {

        // TODO: Split compilation into two steps: kt -> ir, ir -> js
@@ -211,9 +225,17 @@ fun compile(
        }
    }

-    jsPhases.invokeToplevel(context.phaseConfig, context, moduleFragment)
+        val context = JsIrBackendContext(
+            analysisResult.moduleDescriptor,
+            psi2IrContext.irBuiltIns,
+            psi2IrContext.symbolTable,
+            moduleFragment,
+            configuration,
+            irDependencyModules
+        )

-    val jsProgram = moduleFragment.accept(IrModuleToJsTransformer(context), null)
+        val jsProgram = moduleFragment.accept(IrModuleToJsTransformer(context), null)

-    return CompiledModule(moduleName, jsProgram.toString(), context.moduleFragmentCopy, moduleType, dependencies)
+        return CompiledModule(moduleName, jsProgram.toString(), context.moduleFragmentCopy, moduleType, dependencies)
+    }
 }
@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.ir.backend.js.lower

 import org.jetbrains.kotlin.backend.common.DeclarationContainerLoweringPass
+import org.jetbrains.kotlin.backend.common.ir.isElseBranch
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
@@ -366,8 +367,8 @@ class BlockDecomposerTransformer(private val context: JsIrBackendContext) : IrEl

            if (compositeCount == 0) {
                val branches = results.map { (cond, res, orig) ->
-                    when (orig) {
-                        is IrElseBranch -> IrElseBranchImpl(orig.startOffset, orig.endOffset, cond, res)
+                    when {
+                        isElseBranch(orig) -> IrElseBranchImpl(orig.startOffset, orig.endOffset, cond, res)
                        else /* IrBranch */ -> IrBranchImpl(orig.startOffset, orig.endOffset, cond, res)
                    }
                }
@@ -384,7 +385,7 @@ class BlockDecomposerTransformer(private val context: JsIrBackendContext) : IrEl
                appendBlock.statements += condStatements.run { subList(0, lastIndex) }

                JsIrBuilder.buildBlock(unitType).also {
-                    val elseBlock = if (orig is IrElseBranch) null else it
+                    val elseBlock = if (isElseBranch(orig)) null else it
                    val ifElseNode =
                        JsIrBuilder.buildIfElse(orig.startOffset, orig.endOffset, unitType, condValue, res, elseBlock, expression.origin)
                    appendBlock.statements += ifElseNode
@@ -666,9 +667,9 @@ class BlockDecomposerTransformer(private val context: JsIrBackendContext) : IrEl

                val newBranches = decomposedResults.map { (branch, condition, result) ->
                    val newResult = wrap(result, irVar)
-                    when (branch) {
-                        is IrElseBranch -> IrElseBranchImpl(branch.startOffset, branch.endOffset, condition, newResult)
-                        else /* IrBranch */ -> IrBranchImpl(branch.startOffset, branch.endOffset, condition, newResult)
+                    when {
+                        isElseBranch(branch) -> IrElseBranchImpl(branch.startOffset, branch.endOffset, condition, newResult)
+                        else /* IrBranch  */ -> IrBranchImpl(branch.startOffset, branch.endOffset, condition, newResult)
                    }
                }

@@ -679,9 +680,9 @@ class BlockDecomposerTransformer(private val context: JsIrBackendContext) : IrEl
                return JsIrBuilder.buildComposite(expression.type, listOf(irVar, newWhen, JsIrBuilder.buildGetValue(irVar.symbol)))
            } else {
                val newBranches = decomposedResults.map { (branch, condition, result) ->
-                    when (branch) {
-                        is IrElseBranch -> IrElseBranchImpl(branch.startOffset, branch.endOffset, condition, result)
-                        else /* IrBranch */ -> IrBranchImpl(branch.startOffset, branch.endOffset, condition, result)
+                    when {
+                        isElseBranch(branch) -> IrElseBranchImpl(branch.startOffset, branch.endOffset, condition, result)
+                        else /* IrBranch  */ -> IrBranchImpl(branch.startOffset, branch.endOffset, condition, result)
                    }
                }

@@ -5,6 +5,7 @@

 package org.jetbrains.kotlin.ir.backend.js.lower.coroutines

+import org.jetbrains.kotlin.backend.common.ir.isElseBranch
 import org.jetbrains.kotlin.backend.common.ir.isSuspend
 import org.jetbrains.kotlin.backend.common.peek
 import org.jetbrains.kotlin.backend.common.pop
@@ -351,8 +352,8 @@ class StateMachineBuilder(
                if (it.result in suspendableNodes) {
                    suspendableNodes += wrapped
                }
-                when (it) {
-                    is IrElseBranch -> IrElseBranchImpl(it.startOffset, it.endOffset, it.condition, wrapped)
+                when {
+                    isElseBranch(it) -> IrElseBranchImpl(it.startOffset, it.endOffset, it.condition, wrapped)
                    else /* IrBranch */ -> IrBranchImpl(it.startOffset, it.endOffset, it.condition, wrapped)
                }
            }
@@ -365,7 +366,7 @@ class StateMachineBuilder(
        val rootBlock = currentBlock

        for (branch in branches) {
-            if (branch !is IrElseBranch) {
+            if (!isElseBranch(branch)) {
                branch.condition.acceptVoid(this)
                val branchBlock = JsIrBuilder.buildComposite(branch.result.type)
                val elseBlock = JsIrBuilder.buildComposite(expression.type)
@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrReturnableBlockImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrVarargImpl
 import org.jetbrains.kotlin.ir.symbols.impl.IrReturnableBlockSymbolImpl
+import org.jetbrains.kotlin.ir.types.irTypeKotlinBuiltIns
 import org.jetbrains.kotlin.ir.types.toKotlinType
 import org.jetbrains.kotlin.ir.util.file
 import org.jetbrains.kotlin.ir.util.getArguments
@@ -124,6 +125,7 @@ internal class FunctionInlining(val context: Context): IrElementTransformerWithC
    //-------------------------------------------------------------------------//

    fun inline(irModule: IrModuleFragment): IrElement {
+        irTypeKotlinBuiltIns = irModule.irBuiltins.builtIns
        val transformedModule = irModule.accept(this, Ref(false))
        DescriptorSubstitutorForExternalScope(globalSubstituteMap, context).run(transformedModule)   // Transform calls to object that might be returned from inline function call.
        return transformedModule
@@ -371,7 +373,7 @@ private class Inliner(val globalSubstituteMap: MutableMap<DeclarationDescriptor,
        override fun visitElement(element: IrElement) = element.accept(this, null)
    }

-    private fun isLambdaCall(irCall: IrCall)  = irCall.descriptor.isFunctionInvoke && irCall.dispatchReceiver is IrGetValue
+    private fun isLambdaCall(irCall: IrCall) = irCall.symbol.owner.isFunctionInvoke && irCall.dispatchReceiver is IrGetValue

    private fun createTypeSubstitutor(irCall: IrCall): TypeSubstitutor? {
        if (irCall.typeArgumentsCount == 0) return null
@@ -9,6 +9,10 @@ import org.jetbrains.kotlin.builtins.functions.FunctionClassDescriptor
 import org.jetbrains.kotlin.builtins.getFunctionalClassKind
 import org.jetbrains.kotlin.builtins.isFunctionType
 import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
+import org.jetbrains.kotlin.ir.util.isFunctionOrKFunction
+import org.jetbrains.kotlin.ir.util.isFunctionTypeOrSubtype
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.resolve.OverridingUtil
 import org.jetbrains.kotlin.types.KotlinType
@@ -47,6 +51,15 @@ internal val FunctionDescriptor.isFunctionInvoke: Boolean
                this.isOperator && this.name == OperatorNameConventions.INVOKE
    }

+internal val IrFunction.isFunctionInvoke: Boolean
+    get() {
+        val dispatchReceiver = dispatchReceiverParameter ?: return false
+        assert(!dispatchReceiver.type.isFunctionTypeOrSubtype())
+
+        return dispatchReceiver.type.isFunctionTypeOrSubtype() &&
+                /*this.isOperator &&*/ this.name == OperatorNameConventions.INVOKE
+    }
+
 // It is possible to declare "external inline fun",
 // but it doesn't have much sense for native,
 // since externals don't have IR bodies.
@@ -0,0 +1,202 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.backend.common.atMostOne
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
+import org.jetbrains.kotlin.ir.expressions.IrCall
+import org.jetbrains.kotlin.ir.expressions.IrConst
+import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.types.classifierOrFail
+import org.jetbrains.kotlin.ir.types.isMarkedNullable
+import org.jetbrains.kotlin.ir.util.explicitParameters
+import org.jetbrains.kotlin.ir.util.isFunction
+import org.jetbrains.kotlin.ir.util.isInterface
+import org.jetbrains.kotlin.ir.util.isSuspendFunction
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedPropertyDescriptor
+
+val IrConstructor.constructedClass get() = this.parent as IrClass
+
+val <T : IrDeclaration> T.original get() = this
+val IrDeclaration.containingDeclaration get() = this.parent
+
+val IrDeclarationParent.fqNameSafe: FqName
+    get() = when (this) {
+        is IrPackageFragment -> this.fqName
+        is IrDeclaration -> this.parent.fqNameSafe.child(this.name)
+
+        else -> error(this)
+    }
+
+val IrClass.classId: ClassId?
+    get() {
+        val parent = this.parent
+        return when (parent) {
+            is IrClass -> parent.classId?.createNestedClassId(this.name)
+            is IrPackageFragment -> ClassId.topLevel(parent.fqName.child(this.name))
+            else -> null
+        }
+    }
+
+val IrDeclaration.name: Name
+    get() = when (this) {
+        is IrSimpleFunction -> this.name
+        is IrClass -> this.name
+        is IrEnumEntry -> this.name
+        is IrProperty -> this.name
+        is IrLocalDelegatedProperty -> this.name
+        is IrField -> this.name
+        is IrVariable -> this.name
+        is IrConstructor -> SPECIAL_INIT_NAME
+        is IrValueParameter -> this.name
+        else -> error(this)
+    }
+
+private val SPECIAL_INIT_NAME = Name.special("<init>")
+
+val IrField.fqNameSafe: FqName get() = this.parent.fqNameSafe.child(this.name)
+
+/**
+ * @return naturally-ordered list of all parameters available inside the function body.
+ */
+val IrFunction.allParameters: List<IrValueParameter>
+    get() = if (this is IrConstructor) {
+        listOf(this.constructedClass.thisReceiver
+                   ?: error(this.descriptor)
+        ) + explicitParameters
+    } else {
+        explicitParameters
+    }
+
+val IrValueParameter.isVararg get() = this.varargElementType != null
+
+val IrFunction.isSuspend get() = this is IrSimpleFunction && this.isSuspend
+
+fun IrClass.isUnit() = this.fqNameSafe == KotlinBuiltIns.FQ_NAMES.unit.toSafe()
+
+fun IrClass.isKotlinArray() = this.fqNameSafe == KotlinBuiltIns.FQ_NAMES.array.toSafe()
+
+val IrClass.superClasses get() = this.superTypes.map { it.classifierOrFail as IrClassSymbol }
+fun IrClass.getSuperClassNotAny() = this.superClasses.map { it.owner }.atMostOne { !it.isInterface && !it.isAny() }
+
+fun IrClass.isAny() = this.fqNameSafe == KotlinBuiltIns.FQ_NAMES.any.toSafe()
+fun IrClass.isNothing() = this.fqNameSafe == KotlinBuiltIns.FQ_NAMES.nothing.toSafe()
+
+fun IrClass.getSuperInterfaces() = this.superClasses.map { it.owner }.filter { it.isInterface }
+
+val IrProperty.konanBackingField: IrField?
+    get() {
+        assert(this.isReal)
+        this.backingField?.let { return it }
+
+//        (this.descriptor as? DeserializedPropertyDescriptor)?.konanBackingField?.let { backingFieldDescriptor ->
+//            val result = IrFieldImpl(
+//                this.startOffset,
+//                this.endOffset,
+//                IrDeclarationOrigin.PROPERTY_BACKING_FIELD,
+//                backingFieldDescriptor,
+//                this.getter!!.returnType
+//            ).also {
+//                it.parent = this.parent
+//            }
+//            this.backingField = result
+//            return result
+//        }
+
+        return null
+    }
+
+val IrField.containingClass get() = this.parent as? IrClass
+
+val IrFunction.isReal get() = this.origin != IrDeclarationOrigin.FAKE_OVERRIDE
+
+// Note: psi2ir doesn't set `origin = FAKE_OVERRIDE` for fields and properties yet.
+val IrProperty.isReal: Boolean get() = this.descriptor.kind.isReal
+val IrField.isReal: Boolean get() = this.descriptor.kind.isReal
+
+val IrSimpleFunction.isOverridable: Boolean
+    get() = visibility != Visibilities.PRIVATE
+            && modality != Modality.FINAL
+            && (parent as? IrClass)?.isFinalClass != true
+
+val IrFunction.isOverridable get() = this is IrSimpleFunction && this.isOverridable
+
+val IrFunction.isOverridableOrOverrides
+    get() = this is IrSimpleFunction && (this.isOverridable || this.overriddenSymbols.isNotEmpty())
+
+val IrClass.isFinalClass: Boolean
+    get() = modality == Modality.FINAL && kind != ClassKind.ENUM_CLASS
+
+fun IrSimpleFunction.overrides(other: IrSimpleFunction): Boolean {
+    if (this == other) return true
+
+    this.overriddenSymbols.forEach {
+        if (it.owner.overrides(other)) {
+            return true
+        }
+    }
+
+    return false
+}
+
+fun IrClass.isSpecialClassWithNoSupertypes() = this.isAny() || this.isNothing()
+
+internal val IrValueParameter.isValueParameter get() = this.index >= 0
+
+private val IrCall.annotationClass
+    get() = (this.symbol.owner as IrConstructor).constructedClass
+
+fun List<IrCall>.hasAnnotation(fqName: FqName): Boolean =
+    this.any { it.annotationClass.fqNameSafe == fqName }
+
+fun IrAnnotationContainer.hasAnnotation(fqName: FqName) =
+    this.annotations.hasAnnotation(fqName)
+
+fun List<IrCall>.findAnnotation(fqName: FqName): IrCall? = this.firstOrNull {
+    it.annotationClass.fqNameSafe == fqName
+}
+
+fun <T> IrDeclaration.getAnnotationArgumentValue(fqName: FqName, argumentName: String): T? {
+    val annotation = this.annotations.findAnnotation(fqName)
+    if (annotation == null) {
+        // As a last resort try searching the descriptor.
+        // This is needed for a period while we don't have IR for platform libraries.
+        return this.descriptor.annotations
+            .findAnnotation(fqName)
+            ?.getArgumentValueOrNull<T>(argumentName)
+    }
+    for (index in 0 until annotation.valueArgumentsCount) {
+        val parameter = annotation.symbol.owner.valueParameters[index]
+        if (parameter.name == Name.identifier(argumentName)) {
+            val actual = annotation.getValueArgument(index) as? IrConst<T>
+            return actual?.value
+        }
+    }
+    return null
+}
+
+fun IrValueParameter.isInlineParameter(): Boolean =
+    !this.isNoinline && (this.type.isFunction() || this.type.isSuspendFunction()) && !this.type.isMarkedNullable()
+
+val IrDeclaration.parentDeclarationsWithSelf: Sequence<IrDeclaration>
+    get() = generateSequence(this, { it.parent as? IrDeclaration })
+
+fun IrClass.companionObject() = this.declarations.singleOrNull {it is IrClass && it.isCompanion }
+
+val IrDeclaration.isGetter get() = this is IrSimpleFunction && this == this.correspondingProperty?.getter
+
+val IrDeclaration.isSetter get() = this is IrSimpleFunction && this == this.correspondingProperty?.setter
+
+val IrDeclaration.isAccessor get() = this.isGetter || this.isSetter
@@ -0,0 +1,169 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.builtins.functions.FunctionInvokeDescriptor
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
+import org.jetbrains.kotlin.ir.SourceManager
+import org.jetbrains.kotlin.ir.SourceRangeInfo
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
+import org.jetbrains.kotlin.ir.declarations.IrClass
+import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.IrField
+import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
+import org.jetbrains.kotlin.ir.util.parentAsClass
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.psi2ir.findFirstFunction
+import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.descriptorUtil.module
+import java.io.File
+import java.util.regex.Pattern
+
+internal val IrDeclaration.isAnonymousObject get() = DescriptorUtils.isAnonymousObject(this.descriptor)
+internal val IrDeclaration.isLocal get() = DescriptorUtils.isLocal(this.descriptor)
+
+internal val IrDeclaration.module get() = this.descriptor.module
+
+@Deprecated("Do not call this method in the compiler front-end.")
+internal val IrField.isDelegate
+    get() = @Suppress("DEPRECATION") this.descriptor.isDelegated
+
+internal const val SYNTHETIC_OFFSET = -2
+
+class NaiveSourceBasedFileEntryImpl(override val name: String) : SourceManager.FileEntry {
+
+    private val lineStartOffsets: IntArray
+
+    //-------------------------------------------------------------------------//
+
+    init {
+        val file = File(name)
+        if (file.isFile) {
+            // TODO: could be incorrect, if file is not in system's line terminator format.
+            // Maybe use (0..document.lineCount - 1)
+            //                .map { document.getLineStartOffset(it) }
+            //                .toIntArray()
+            // as in PSI.
+            val separatorLength = System.lineSeparator().length
+            val buffer = mutableListOf<Int>()
+            var currentOffset = 0
+            file.forEachLine { line ->
+                buffer.add(currentOffset)
+                currentOffset += line.length + separatorLength
+            }
+            buffer.add(currentOffset)
+            lineStartOffsets = buffer.toIntArray()
+        } else {
+            lineStartOffsets = IntArray(0)
+        }
+    }
+
+    //-------------------------------------------------------------------------//
+
+    override fun getLineNumber(offset: Int): Int {
+        assert(offset != UNDEFINED_OFFSET)
+        if (offset == SYNTHETIC_OFFSET) return 0
+        val index = lineStartOffsets.binarySearch(offset)
+        return if (index >= 0) index else -index - 2
+    }
+
+    //-------------------------------------------------------------------------//
+
+    override fun getColumnNumber(offset: Int): Int {
+        assert(offset != UNDEFINED_OFFSET)
+        if (offset == SYNTHETIC_OFFSET) return 0
+        var lineNumber = getLineNumber(offset)
+        return offset - lineStartOffsets[lineNumber]
+    }
+
+    //-------------------------------------------------------------------------//
+
+    override val maxOffset: Int
+        //get() = TODO("not implemented")
+        get() = UNDEFINED_OFFSET
+
+    override fun getSourceRangeInfo(beginOffset: Int, endOffset: Int): SourceRangeInfo {
+        //TODO("not implemented")
+        return SourceRangeInfo(name, beginOffset, -1, -1, endOffset, -1, -1)
+
+    }
+}
+
+
+private val functionPattern = Pattern.compile("^K?(Suspend)?Function\\d+$")
+
+private val kotlinFqn = FqName("kotlin")
+
+private val functionalPackages =
+    listOf(kotlinFqn, kotlinFqn.child(Name.identifier("coroutines")), kotlinFqn.child(Name.identifier("reflect")))
+
+internal val BUILT_IN_FUNCTION_CLASS_COUNT = 4
+internal val BUILT_IN_FUNCTION_ARITY_COUNT = 256
+internal val BUILT_IN_UNIQ_ID_GAP = 2 * BUILT_IN_FUNCTION_ARITY_COUNT * BUILT_IN_FUNCTION_CLASS_COUNT
+internal val BUILT_IN_UNIQ_ID_CLASS_OFFSET = BUILT_IN_FUNCTION_CLASS_COUNT * BUILT_IN_FUNCTION_ARITY_COUNT
+
+internal fun isBuiltInFunction(value: IrDeclaration): Boolean = when (value) {
+    is IrSimpleFunction -> value.name.asString() == "invoke" && (value.parent as? IrClass)?.let { isBuiltInFunction(it) } == true
+    is IrClass -> {
+        val fqn = value.parent.fqNameSafe
+        functionalPackages.any { it == fqn } && value.name.asString().let { functionPattern.matcher(it).find() }
+    }
+    else -> false
+}
+
+
+private fun builtInOffset(function: IrSimpleFunction): Long {
+    val isK = function.parentAsClass.name.asString().startsWith("K")
+    return when {
+        isK && function.isSuspend -> 3
+        isK -> 2
+        function.isSuspend -> 1
+        else -> 0
+    }
+}
+
+internal fun builtInFunctionId(value: IrDeclaration): Long = when (value) {
+    is IrSimpleFunction -> {
+        value.run { valueParameters.size + builtInOffset(value) * BUILT_IN_FUNCTION_ARITY_COUNT }.toLong()
+    }
+    is IrClass -> {
+        BUILT_IN_UNIQ_ID_CLASS_OFFSET + builtInFunctionId(value.declarations.first { it.name.asString() == "invoke" })
+    }
+    else -> error("Only class or function is expected")
+}
+
+
+internal fun isBuiltInFunction(value: DeclarationDescriptor): Boolean = when (value) {
+    is FunctionInvokeDescriptor -> isBuiltInFunction(value.containingDeclaration)
+    is ClassDescriptor -> {
+        val fqn = (value.containingDeclaration as? PackageFragmentDescriptor)?.fqName
+        functionalPackages.any { it == fqn } && value.name.asString().let { functionPattern.matcher(it).find() }
+    }
+    else -> false
+}
+
+private fun builtInOffset(function: FunctionInvokeDescriptor): Long {
+    val isK = function.containingDeclaration.name.asString().startsWith("K")
+    return when {
+        isK && function.isSuspend -> 3
+        isK -> 2
+        function.isSuspend -> 1
+        else -> 0
+    }
+}
+
+internal fun builtInFunctionId(value: DeclarationDescriptor): Long = when (value) {
+    is FunctionInvokeDescriptor -> {
+        value.run { valueParameters.size + builtInOffset(value) * BUILT_IN_FUNCTION_ARITY_COUNT }.toLong()
+    }
+    is ClassDescriptor -> {
+        BUILT_IN_UNIQ_ID_CLASS_OFFSET + builtInFunctionId(value.findFirstFunction("invoke") { true })
+    }
+    else -> error("Only class or function is expected")
+}
@@ -0,0 +1,252 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.ModuleDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyAccessorDescriptor
+import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.descriptors.Visibility
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
+import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.util.isInlined
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+
+
+// This file describes the ABI for Kotlin descriptors of exported declarations.
+// TODO: revise the naming scheme to ensure it produces unique names.
+// TODO: do not serialize descriptors of non-exported declarations.
+
+/**
+ * Defines whether the declaration is exported, i.e. visible from other modules.
+ *
+ * Exported declarations must have predictable and stable ABI
+ * that doesn't depend on any internal transformations (e.g. IR lowering),
+ * and so should be computable from the descriptor itself without checking a backend state.
+ */
+internal tailrec fun IrDeclaration.isExported(): Boolean {
+    // TODO: revise
+    val descriptorAnnotations = this.descriptor.annotations
+//    if (descriptorAnnotations.hasAnnotation(symbolNameAnnotation)) {
+//        // Treat any `@SymbolName` declaration as exported.
+//        return true
+//    }
+//    if (descriptorAnnotations.hasAnnotation(exportForCppRuntimeAnnotation)) {
+//        // Treat any `@ExportForCppRuntime` declaration as exported.
+//        return true
+//    }
+//    if (descriptorAnnotations.hasAnnotation(cnameAnnotation)) {
+//        // Treat `@CName` declaration as exported.
+//        return true
+//    }
+//    if (descriptorAnnotations.hasAnnotation(exportForCompilerAnnotation)) {
+//        return true
+//    }
+    if (descriptorAnnotations.hasAnnotation(publishedApiAnnotation)){
+        return true
+    }
+
+    if (this.isAnonymousObject)
+        return false
+
+    if (this is IrConstructor && constructedClass.kind.isSingleton) {
+        // Currently code generator can access the constructor of the singleton,
+        // so ignore visibility of the constructor itself.
+        return constructedClass.isExported()
+    }
+
+    if (this is IrFunction) {
+        val descriptor = this.descriptor
+        // TODO: this code is required because accessor doesn't have a reference to property.
+        if (descriptor is PropertyAccessorDescriptor) {
+            val property = descriptor.correspondingProperty
+            if (property.annotations.hasAnnotation(publishedApiAnnotation)) return true
+        }
+    }
+
+    val visibility = when (this) {
+        is IrClass -> this.visibility
+        is IrFunction -> this.visibility
+        is IrProperty -> this.visibility
+        is IrField -> this.visibility
+        else -> null
+    }
+
+    /**
+     * note: about INTERNAL - with support of friend modules we let frontend to deal with internal declarations.
+     */
+    if (visibility != null && !visibility.isPublicAPI && visibility != Visibilities.INTERNAL) {
+        // If the declaration is explicitly marked as non-public,
+        // then it must not be accessible from other modules.
+        return false
+    }
+
+    val parent = this.parent
+    if (parent is IrDeclaration) {
+        return parent.isExported()
+    }
+
+    return true
+}
+
+private val publishedApiAnnotation = FqName("kotlin.PublishedApi")
+
+private fun acyclicTypeMangler(visited: MutableSet<IrTypeParameter>, type: IrType): String {
+    val descriptor = (type.classifierOrNull as? IrTypeParameterSymbol)?.owner
+    if (descriptor != null) {
+        val upperBounds = if (visited.contains(descriptor)) "" else {
+
+            visited.add(descriptor)
+
+            descriptor.superTypes.map {
+                val bound = acyclicTypeMangler(visited, it)
+                if (bound == "kotlin.Any?") "" else "_$bound"
+            }.joinToString("")
+        }
+        return "#GENERIC${if (type.isMarkedNullable()) "?" else ""}$upperBounds"
+    }
+
+    var hashString = type.getClass()?.run { fqNameSafe.asString() } ?: "<dynamic>"
+//    if (type !is IrSimpleType) error(type)
+    when (type) {
+        is IrSimpleType -> {
+            if (!type.arguments.isEmpty()) {
+                hashString += "<${type.arguments.map {
+                    when (it) {
+                        is IrStarProjection -> "#STAR"
+                        is IrTypeProjection -> {
+                            val variance = it.variance.label
+                            val projection = if (variance == "") "" else "${variance}_"
+                            projection + acyclicTypeMangler(visited, it.type)
+                        }
+                        else -> error(it)
+                    }
+                }.joinToString(",")}>"
+            }
+
+            if (type.hasQuestionMark) hashString += "?"
+        }
+        !is IrDynamicType -> { error(type) }
+    }
+    return hashString
+}
+
+private fun typeToHashString(type: IrType) = acyclicTypeMangler(mutableSetOf(), type)
+
+internal val IrValueParameter.extensionReceiverNamePart: String
+    get() = "@${typeToHashString(this.type)}."
+
+private val IrFunction.signature: String
+    get() {
+        val extensionReceiverPart = this.extensionReceiverParameter?.extensionReceiverNamePart ?: ""
+        val argsPart = this.valueParameters.map {
+
+            // TODO: there are clashes originating from ObjectiveC interop.
+            // kotlinx.cinterop.ObjCClassOf<T>.create(format: kotlin.String): T defined in platform.Foundation in file Foundation.kt
+            // and
+            // kotlinx.cinterop.ObjCClassOf<T>.create(string: kotlin.String): T defined in platform.Foundation in file Foundation.kt
+
+            val argName = /*if (this.hasObjCMethodAnnotation || this.hasObjCFactoryAnnotation || this.isObjCClassMethod()) "${it.name}:" else */""
+            "$argName${typeToHashString(it.type)}${if (it.isVararg) "_VarArg" else ""}"
+        }.joinToString(";")
+        // Distinguish value types and references - it's needed for calling virtual methods through bridges.
+        // Also is function has type arguments - frontend allows exactly matching overrides.
+        val signatureSuffix =
+            when {
+                this.typeParameters.isNotEmpty() -> "Generic"
+                returnType.isInlined() -> "ValueType"
+                !returnType.isUnitOrNullableUnit() -> typeToHashString(returnType)
+                else -> ""
+            }
+        return "$extensionReceiverPart($argsPart)$signatureSuffix"
+    }
+
+// TODO: rename to indicate that it has signature included
+internal val IrFunction.functionName: String
+    get() {
+        with(this.original) { // basic support for generics
+//            (if (this is IrConstructor && this.isObjCConstructor) this.getObjCInitMethod() else this)?.getObjCMethodInfo()?.let {
+//                return buildString {
+//                    if (extensionReceiverParameter != null) {
+//                        append(extensionReceiverParameter!!.type.getClass()!!.name)
+//                        append(".")
+//                    }
+//
+//                    append("objc:")
+//                    append(it.selector)
+//                    if (this@with is IrConstructor && this@with.isObjCConstructor) append("#Constructor")
+//
+//                    // We happen to have the clashing combinations such as
+//                    //@ObjCMethod("issueChallengeToPlayers:message:", "objcKniBridge1165")
+//                    //external fun GKScore.issueChallengeToPlayers(playerIDs: List<*>?, message: String?): Unit
+//                    //@ObjCMethod("issueChallengeToPlayers:message:", "objcKniBridge1172")
+//                    //external fun GKScore.issueChallengeToPlayers(playerIDs: List<*>?, message: String?): Unit
+//                    // So disambiguate by the name of the bridge for now.
+//                    // TODO: idealy we'd never generate such identical declarations.
+//
+//                    if (this@with is IrSimpleFunction && this@with.hasObjCMethodAnnotation()) {
+//                        this@with.objCMethodArgValue("selector") ?.let { append("#$it") }
+//                        this@with.objCMethodArgValue("bridge") ?.let { append("#$it") }
+//                    }
+//                }
+//            }
+
+            val name = this.name.mangleIfInternal(this.module, this.visibility)
+
+            return "$name$signature"
+        }
+    }
+
+private fun Name.mangleIfInternal(moduleDescriptor: ModuleDescriptor, visibility: Visibility): String =
+    if (visibility != Visibilities.INTERNAL) {
+        this.asString()
+    } else {
+        val moduleName = moduleDescriptor.name.asString()
+            .let { it.substring(1, it.lastIndex) } // Remove < and >.
+
+        "$this\$$moduleName"
+    }
+
+internal val IrFunction.symbolName: String
+    get() {
+        if (!this.isExported()) {
+            throw AssertionError(this.descriptor.toString())
+        }
+
+        if (isExternal) {
+            this.descriptor.externalSymbolOrThrow()?.let {
+                return it
+            }
+        }
+
+//        this.descriptor.annotations.findAnnotation(exportForCppRuntimeAnnotation)?.let {
+//            val name = getAnnotationValue(it) ?: this.name.asString()
+//            return name // no wrapping currently required
+//        }
+
+        val parent = this.parent
+
+        val containingDeclarationPart = parent.fqNameSafe.let {
+            if (it.isRoot) "" else "$it."
+        }
+        return "kfun:$containingDeclarationPart$functionName"
+    }
+
+internal val IrField.symbolName: String
+    get() {
+        val containingDeclarationPart = parent.fqNameSafe.let {
+            if (it.isRoot) "" else "$it."
+        }
+        return "kfield:$containingDeclarationPart$name"
+
+    }
+
+internal val IrClass.typeInfoSymbolName: String
+    get() {
+        assert (this.isExported())
+        return "ktype:" + this.fqNameSafe.toString()
+    }
@@ -0,0 +1,91 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.backend.common.descriptors.getFunction
+import org.jetbrains.kotlin.descriptors.CallableDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.incremental.components.NoLookupLocation
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.declarations.impl.IrAnonymousInitializerImpl
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.util.SymbolTable
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.resolve.jvm.modules.KOTLIN_STDLIB_MODULE_NAME
+import java.util.regex.Pattern
+
+fun <K, V> MutableMap<K, V>.putOnce(k:K, v: V): Unit {
+    assert(!this.containsKey(k) || this[k] == v) {
+        "adding $v for $k, but it is already ${this[k]} for $k"
+    }
+    this.put(k, v)
+}
+
+class DescriptorTable {
+    private val descriptors = mutableMapOf<DeclarationDescriptor, Long>()
+    fun put(descriptor: DeclarationDescriptor, uniqId: UniqId) {
+        descriptors.putOnce(descriptor, uniqId.index)
+    }
+    fun get(descriptor: DeclarationDescriptor) = descriptors[descriptor]
+}
+
+// TODO: We don't manage id clashes anyhow now.
+class DeclarationTable(val builtIns: IrBuiltIns, val descriptorTable: DescriptorTable, val symbolTable: SymbolTable) {
+
+    private val table = mutableMapOf<IrDeclaration, UniqId>()
+    val debugIndex = mutableMapOf<UniqId, String>()
+    val descriptors = descriptorTable
+    private var currentIndex = 0x1_0000_0000L
+
+    private val FUNCTION_INDEX_START: Long
+
+    init {
+        val known = builtIns.knownBuiltins
+        known.forEach {
+            table.put(it, UniqId(currentIndex++, false))
+        }
+
+        FUNCTION_INDEX_START = currentIndex
+        currentIndex += BUILT_IN_UNIQ_ID_GAP
+    }
+
+    fun uniqIdByDeclaration(value: IrDeclaration): UniqId {
+        val index = table.getOrPut(value) {
+
+            if (isBuiltInFunction(value)) {
+                UniqId(FUNCTION_INDEX_START + builtInFunctionId(value), false)
+            } else if (value.origin == IrDeclarationOrigin.FAKE_OVERRIDE ||
+                !value.isExported()
+                    || value is IrVariable
+                    || value is IrTypeParameter
+                    || value is IrValueParameter
+                    || value is IrAnonymousInitializerImpl
+            ) {
+
+                val desc = value.descriptor
+                if (desc is CallableDescriptor) {
+                    if (desc.visibility == Visibilities.PUBLIC || value.origin != IrDeclarationOrigin.FAKE_OVERRIDE) {
+                        fun foo(){}
+                        foo()
+                    }
+                }
+                UniqId(currentIndex++, true)
+            } else {
+                UniqId(value.uniqIdIndex, false)
+            }
+        }
+
+        debugIndex.put(index, "${if (index.isLocal) "" else value.uniqSymbolName()} descriptor = ${value.descriptor}")
+
+        return index
+    }
+}
+
+// This is what we pre-populate tables with
+val IrBuiltIns.knownBuiltins
+    get() = irBuiltInsExternalPackageFragment.declarations
@@ -0,0 +1,206 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.types.isUnit
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
+import org.jetbrains.kotlin.resolve.descriptorUtil.getSuperClassNotAny
+import org.jetbrains.kotlin.resolve.descriptorUtil.getSuperInterfaces
+import org.jetbrains.kotlin.types.SimpleType
+import org.jetbrains.kotlin.types.typeUtil.isUnit
+
+/**
+ * List of all implemented interfaces (including those which implemented by a super class)
+ */
+internal val IrClass.implementedInterfaces: List<IrClass>
+    get() {
+        val superClassImplementedInterfaces = this.getSuperClassNotAny()?.implementedInterfaces ?: emptyList()
+        val superInterfaces = this.getSuperInterfaces()
+        val superInterfacesImplementedInterfaces = superInterfaces.flatMap { it.implementedInterfaces }
+        return (superClassImplementedInterfaces +
+                superInterfacesImplementedInterfaces +
+                superInterfaces).distinct()
+    }
+
+
+/**
+ * Implementation of given method.
+ *
+ * TODO: this method is actually a part of resolve and probably duplicates another one
+ */
+internal fun IrSimpleFunction.resolveFakeOverride(allowAbstract: Boolean = false): IrSimpleFunction {
+    if (this.isReal) {
+        return this
+    }
+
+    val visited = mutableSetOf<IrSimpleFunction>()
+    val realSupers = mutableSetOf<IrSimpleFunction>()
+
+    fun findRealSupers(function: IrSimpleFunction) {
+        if (function in visited) return
+        visited += function
+        if (function.isReal) {
+            realSupers += function
+        } else {
+            function.overriddenSymbols.forEach { findRealSupers(it.owner) }
+        }
+    }
+
+    findRealSupers(this)
+
+    if (realSupers.size > 1) {
+        visited.clear()
+
+        fun excludeOverridden(function: IrSimpleFunction) {
+            if (function in visited) return
+            visited += function
+            function.overriddenSymbols.forEach {
+                realSupers.remove(it.owner)
+                excludeOverridden(it.owner)
+            }
+        }
+
+        realSupers.toList().forEach { excludeOverridden(it) }
+    }
+
+    return realSupers.first { allowAbstract || it.modality != Modality.ABSTRACT }
+}
+
+// TODO: don't forget to remove descriptor access here.
+//internal val FunctionDescriptor.isTypedIntrinsic: Boolean
+//    get() = this.descriptor.isTypedIntrinsic
+//
+//internal val DeclarationDescriptor.isFrozen: Boolean
+//    get() = this.descriptor.isFrozen
+
+internal val arrayTypes = setOf(
+    "kotlin.Array",
+    "kotlin.ByteArray",
+    "kotlin.CharArray",
+    "kotlin.ShortArray",
+    "kotlin.IntArray",
+    "kotlin.LongArray",
+    "kotlin.FloatArray",
+    "kotlin.DoubleArray",
+    "kotlin.BooleanArray",
+    "kotlin.native.ImmutableBlob",
+    "kotlin.native.internal.NativePtrArray"
+)
+
+
+internal val IrClass.isArray: Boolean
+    get() = this.fqNameSafe.asString() in arrayTypes
+
+
+internal val IrClass.isInterface: Boolean
+    get() = (this.kind == ClassKind.INTERFACE)
+
+fun IrClass.isAbstract() = this.modality == Modality.SEALED || this.modality == Modality.ABSTRACT
+        || this.kind == ClassKind.ENUM_CLASS
+
+//internal fun FunctionDescriptor.hasValueTypeAt(index: Int): Boolean {
+//    when (index) {
+//        0 -> return !isSuspend && returnType.let { (it.isInlined() || it.isUnit()) }
+//        1 -> return dispatchReceiverParameter.let { it != null && it.type.isInlined() }
+//        2 -> return extensionReceiverParameter.let { it != null && it.type.isInlined() }
+//        else -> return this.valueParameters[index - 3].type.isInlined()
+//    }
+//}
+//
+//internal fun FunctionDescriptor.hasReferenceAt(index: Int): Boolean {
+//    when (index) {
+//        0 -> return isSuspend || returnType.let { !it.isInlined() && !it.isUnit() }
+//        1 -> return dispatchReceiverParameter.let { it != null && !it.type.isInlined() }
+//        2 -> return extensionReceiverParameter.let { it != null && !it.type.isInlined() }
+//        else -> return !this.valueParameters[index - 3].type.isInlined()
+//    }
+//}
+
+//private fun FunctionDescriptor.needBridgeToAt(target: FunctionDescriptor, index: Int)
+//        = hasValueTypeAt(index) xor target.hasValueTypeAt(index)
+
+//internal fun FunctionDescriptor.needBridgeTo(target: FunctionDescriptor)
+//        = (0..this.valueParameters.size + 2).any { needBridgeToAt(target, it) }
+
+internal val IrSimpleFunction.target: IrSimpleFunction
+    get() = (if (modality == Modality.ABSTRACT) this else resolveFakeOverride()).original
+
+internal val IrFunction.target: IrFunction get() = when (this) {
+    is IrSimpleFunction -> this.target
+    is IrConstructor -> this
+    else -> error(this)
+}
+
+//private fun FunctionDescriptor.bridgeDirectionToAt(target: FunctionDescriptor, index: Int)
+//        = when {
+//    hasValueTypeAt(index) && target.hasReferenceAt(index) -> BridgeDirection.FROM_VALUE_TYPE
+//    hasReferenceAt(index) && target.hasValueTypeAt(index) -> BridgeDirection.TO_VALUE_TYPE
+//    else -> BridgeDirection.NOT_NEEDED
+//}
+
+val IrSimpleFunction.allOverriddenDescriptors: Set<IrSimpleFunction>
+    get() {
+        val result = mutableSetOf<IrSimpleFunction>()
+
+        fun traverse(function: IrSimpleFunction) {
+            if (function in result) return
+            result += function
+            function.overriddenSymbols.forEach { traverse(it.owner) }
+        }
+
+        traverse(this)
+
+        return result
+    }
+
+//internal fun IrSimpleFunction.bridgeDirectionsTo(
+//    overriddenDescriptor: IrSimpleFunction
+//): BridgeDirections {
+//    val ourDirections = BridgeDirections(this.valueParameters.size)
+//    for (index in ourDirections.array.indices)
+//        ourDirections.array[index] = this.bridgeDirectionToAt(overriddenDescriptor, index)
+//
+//    val target = this.target
+//    if (!this.isReal && modality != Modality.ABSTRACT
+//        && target.overrides(overriddenDescriptor)
+//        && ourDirections == target.bridgeDirectionsTo(overriddenDescriptor)) {
+//        // Bridge is inherited from superclass.
+//        return BridgeDirections(this.valueParameters.size)
+//    }
+//
+//    return ourDirections
+//}
+
+tailrec internal fun IrDeclaration.findPackage(): IrPackageFragment {
+    val parent = this.parent
+    return parent as? IrPackageFragment
+        ?: (parent as IrDeclaration).findPackage()
+}
+
+fun IrFunction.isComparisonDescriptor(map: Map<SimpleType, IrSimpleFunction>): Boolean =
+    this in map.values
+
+val IrDeclaration.isPropertyAccessor get() =
+    this is IrSimpleFunction && this.correspondingProperty != null
+
+val IrDeclaration.isPropertyField get() =
+    this is IrField && this.correspondingProperty != null
+
+val IrDeclaration.isTopLevelDeclaration get() =
+    parent !is IrDeclaration && !this.isPropertyAccessor && !this.isPropertyField
+
+fun IrDeclaration.findTopLevelDeclaration(): IrDeclaration = when {
+    this.isTopLevelDeclaration ->
+        this
+    this.isPropertyAccessor ->
+        (this as IrSimpleFunction).correspondingProperty!!.findTopLevelDeclaration()
+    this.isPropertyField ->
+        (this as IrField).correspondingProperty!!.findTopLevelDeclaration()
+    else ->
+        (this.parent as IrDeclaration).findTopLevelDeclaration()
+}
@@ -0,0 +1,94 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.incremental.components.NoLookupLocation
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameUnsafe
+import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedClassDescriptor
+
+class DescriptorReferenceDeserializer(val currentModule: ModuleDescriptor, val resolvedForwardDeclarations: MutableMap<UniqIdKey, UniqIdKey>) {
+
+    fun deserializeDescriptorReference(
+        proto: IrKlibProtoBuf.DescriptorReference,
+        checkerDesc: (DeclarationDescriptor) -> Long?,
+        checkerID: (Long) -> Boolean,
+        descriptorResolver: (FqName) -> DeclarationDescriptor
+    ): DeclarationDescriptor {
+        val packageFqName =
+            if (proto.packageFqName == "<root>") FqName.ROOT else FqName(proto.packageFqName) // TODO: whould we store an empty string in the protobuf?
+        val classFqName = FqName(proto.classFqName)
+        val protoIndex = if (proto.hasUniqId()) proto.uniqId.index else null
+
+        val (clazz, members) = if (proto.classFqName == "") {
+            Pair(null, currentModule.getPackage(packageFqName).memberScope.getContributedDescriptors())
+        } else {
+            val clazz = currentModule.findClassAcrossModuleDependencies(ClassId(packageFqName, classFqName, false))!!
+            Pair(clazz, clazz.unsubstitutedMemberScope.getContributedDescriptors() + clazz.getConstructors())
+        }
+
+        if (proto.packageFqName.startsWith("cnames.") || proto.packageFqName.startsWith("objcnames.")) {
+            val descriptor =
+                currentModule.findClassAcrossModuleDependencies(ClassId(packageFqName, FqName(proto.name), false))!!
+            if (!descriptor.fqNameUnsafe.asString().startsWith("cnames") && !descriptor.fqNameUnsafe.asString().startsWith(
+                    "objcnames"
+                )
+            ) {
+                if (descriptor is DeserializedClassDescriptor) {
+                    val uniqId = UniqId(descriptor.getUniqId()!!.index, false)
+                    val newKey = UniqIdKey(null, uniqId)
+                    val oldKey = UniqIdKey(null, UniqId(protoIndex!!, false))
+
+                    resolvedForwardDeclarations.put(oldKey, newKey)
+                } else {
+                    /* ??? */
+                }
+            }
+            return descriptor
+        }
+
+        if (proto.isEnumEntry) {
+            val name = proto.name
+            val memberScope = (clazz as DeserializedClassDescriptor).getUnsubstitutedMemberScope()
+            return memberScope.getContributedClassifier(Name.identifier(name), NoLookupLocation.FROM_BACKEND)!!
+        }
+
+        if (proto.isEnumSpecial) {
+            val name = proto.name
+            return clazz!!.getStaticScope()
+                .getContributedFunctions(Name.identifier(name), NoLookupLocation.FROM_BACKEND).single()
+        }
+
+        if (protoIndex?.let { checkerID(it) } == true) {
+            return descriptorResolver(packageFqName.child(Name.identifier(proto.name)))
+        }
+
+        members.forEach { member ->
+            if (proto.isDefaultConstructor && member is ClassConstructorDescriptor) return member
+
+            val realMembers =
+                if (proto.isFakeOverride && member is CallableMemberDescriptor && member.kind == CallableMemberDescriptor.Kind.FAKE_OVERRIDE)
+                    member.resolveFakeOverrideMaybeAbstract().map { it.original }
+                else
+                    setOf(member)
+
+            val memberIndices = realMembers.map { it.getUniqId()?.index ?: checkerDesc(it) }.filterNotNull()
+
+            if (memberIndices.contains(protoIndex)) {
+                return when {
+                    member is PropertyDescriptor && proto.isSetter -> member.setter!!
+                    member is PropertyDescriptor && proto.isGetter -> member.getter!!
+                    else -> member
+                }
+            }
+        }
+
+        error("Could not find serialized descriptor for index: ${proto.uniqId.index} ${proto.packageFqName},${proto.classFqName},${proto.name}")
+    }
+}
@@ -0,0 +1,337 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.backend.common.LoggingContext
+import org.jetbrains.kotlin.backend.common.descriptors.*
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.impl.EmptyPackageFragmentDescriptor
+import org.jetbrains.kotlin.incremental.components.NoLookupLocation
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
+import org.jetbrains.kotlin.ir.backend.js.lower.serialization.metadata.JsKlibMetadataSerializerProtocol
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.declarations.impl.*
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.symbols.*
+import org.jetbrains.kotlin.ir.symbols.impl.*
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.util.SymbolTable
+import org.jetbrains.kotlin.ir.util.patchDeclarationParents
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.resolve.descriptorUtil.module
+import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedCallableMemberDescriptor
+import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedClassDescriptor
+import java.io.File
+
+class IrKlibProtoBufModuleDeserializer(
+    currentModule: ModuleDescriptor,
+    logger: LoggingContext,
+    builtIns: IrBuiltIns,
+    libraryDir: File,
+    symbolTable: SymbolTable,
+    val forwardModuleDescriptor: ModuleDescriptor?)
+        : IrModuleDeserializer(logger, builtIns, symbolTable) {
+
+    val deserializedSymbols = mutableMapOf<UniqIdKey, IrSymbol>()
+    val knownBuiltInsDescriptors = mutableMapOf<DeclarationDescriptor, UniqId>()
+    val reachableTopLevels = mutableSetOf<UniqIdKey>()
+    val deserializedTopLevels = mutableSetOf<UniqIdKey>()
+    val forwardDeclarations = mutableSetOf<IrSymbol>()
+
+    var deserializedModuleDescriptor: ModuleDescriptor? = null
+    var deserializedModuleProtoSymbolTables = mutableMapOf<ModuleDescriptor, IrKlibProtoBuf.IrSymbolTable>()
+    var deserializedModuleProtoTypeTables = mutableMapOf<ModuleDescriptor, IrKlibProtoBuf.IrTypeTable>()
+
+    val resolvedForwardDeclarations = mutableMapOf<UniqIdKey, UniqIdKey>()
+    val descriptorReferenceDeserializer = DescriptorReferenceDeserializer(currentModule, resolvedForwardDeclarations)
+
+    val moduleRoot = libraryDir
+    val irDirectory = File(libraryDir, "ir/")
+
+
+    private val FUNCTION_INDEX_START: Long
+
+    init {
+        var currentIndex = 0x1_0000_0000L
+        builtIns.knownBuiltins.forEach {
+            require(it is IrFunction)
+            deserializedSymbols.put(UniqIdKey(null, UniqId(currentIndex, isLocal = false)), it.symbol)
+            assert(symbolTable.referenceSimpleFunction(it.descriptor) == it.symbol)
+            currentIndex++
+        }
+
+        FUNCTION_INDEX_START = currentIndex
+    }
+
+    private fun referenceDeserializedSymbol(proto: IrKlibProtoBuf.IrSymbolData, descriptor: DeclarationDescriptor?): IrSymbol = when (proto.kind) {
+        IrKlibProtoBuf.IrSymbolKind.ANONYMOUS_INIT_SYMBOL ->
+            IrAnonymousInitializerSymbolImpl(
+                descriptor as ClassDescriptor?
+                    ?: WrappedClassDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.CLASS_SYMBOL ->
+            symbolTable.referenceClass(
+                descriptor as ClassDescriptor?
+                    ?: WrappedClassDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.CONSTRUCTOR_SYMBOL ->
+            symbolTable.referenceConstructor(
+                descriptor as ClassConstructorDescriptor?
+                    ?: WrappedClassConstructorDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.TYPE_PARAMETER_SYMBOL ->
+            symbolTable.referenceTypeParameter(
+                descriptor as TypeParameterDescriptor?
+                    ?: WrappedTypeParameterDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.ENUM_ENTRY_SYMBOL ->
+            symbolTable.referenceEnumEntry(
+                descriptor as ClassDescriptor?
+                    ?: WrappedEnumEntryDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.STANDALONE_FIELD_SYMBOL ->
+            IrFieldSymbolImpl(WrappedFieldDescriptor())
+
+        IrKlibProtoBuf.IrSymbolKind.FIELD_SYMBOL ->
+            symbolTable.referenceField(
+                descriptor as PropertyDescriptor?
+                    ?: WrappedPropertyDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.FUNCTION_SYMBOL ->
+            symbolTable.referenceSimpleFunction(
+                descriptor as FunctionDescriptor?
+                    ?: WrappedSimpleFunctionDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.VARIABLE_SYMBOL ->
+            IrVariableSymbolImpl(
+                descriptor as VariableDescriptor?
+                    ?: WrappedVariableDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.VALUE_PARAMETER_SYMBOL ->
+            IrValueParameterSymbolImpl(
+                descriptor as ParameterDescriptor?
+                    ?: WrappedValueParameterDescriptor()
+            )
+        IrKlibProtoBuf.IrSymbolKind.RECEIVER_PARAMETER_SYMBOL ->
+            IrValueParameterSymbolImpl(
+                descriptor as ParameterDescriptor? ?: WrappedReceiverParameterDescriptor()
+            )
+        else -> TODO("Unexpected classifier symbol kind: ${proto.kind}")
+    }
+
+    override fun deserializeIrSymbol(proto: IrKlibProtoBuf.IrSymbol): IrSymbol {
+        val symbolData =
+            deserializedModuleProtoSymbolTables[deserializedModuleDescriptor]!!.getSymbols(proto.index)
+        return deserializeIrSymbolData(symbolData)
+    }
+
+    override fun deserializeIrType(proto: IrKlibProtoBuf.IrTypeIndex): IrType {
+        val typeData =
+            deserializedModuleProtoTypeTables[deserializedModuleDescriptor]!!.getTypes(proto.index)
+        return deserializeIrTypeData(typeData)
+    }
+
+    fun deserializeIrSymbolData(proto: IrKlibProtoBuf.IrSymbolData): IrSymbol {
+        val key = proto.uniqId.uniqIdKey(deserializedModuleDescriptor!!)
+        val topLevelKey = proto.topLevelUniqId.uniqIdKey(deserializedModuleDescriptor!!)
+
+        if (!deserializedTopLevels.contains(topLevelKey)) reachableTopLevels.add(topLevelKey)
+
+        val symbol = deserializedSymbols.getOrPut(key) {
+            val descriptor = if (proto.hasDescriptorReference()) {
+                deserializeDescriptorReference(proto.descriptorReference)
+            } else {
+                null
+            }
+
+            resolvedForwardDeclarations[key]?.let {
+                if (!deserializedTopLevels.contains(it)) reachableTopLevels.add(it) // Assuming forward declarations are always top levels.
+            }
+
+            referenceDeserializedSymbol(proto, descriptor)
+        }
+
+        if (symbol.descriptor is ClassDescriptor &&
+            symbol.descriptor !is WrappedDeclarationDescriptor<*>/* &&
+            symbol.descriptor.module.isForwardDeclarationModule*/
+        ) {
+            forwardDeclarations.add(symbol)
+        }
+
+        return symbol
+    }
+
+    override fun deserializeDescriptorReference(proto: IrKlibProtoBuf.DescriptorReference) =
+        descriptorReferenceDeserializer.deserializeDescriptorReference(proto, {
+            knownBuiltInsDescriptors[it]?.index ?: if (isBuiltInFunction(it)) FUNCTION_INDEX_START + builtInFunctionId(it) else null
+        }, { (FUNCTION_INDEX_START + BUILT_IN_UNIQ_ID_CLASS_OFFSET) <= it && it < (FUNCTION_INDEX_START + BUILT_IN_UNIQ_ID_GAP) }, {
+            builtIns.builtIns.getBuiltInClassByFqName(it)
+        })
+
+    private val ByteArray.codedInputStream: org.jetbrains.kotlin.protobuf.CodedInputStream
+        get() {
+            val codedInputStream = org.jetbrains.kotlin.protobuf.CodedInputStream.newInstance(this)
+            codedInputStream.setRecursionLimit(65535) // The default 64 is blatantly not enough for IR.
+            return codedInputStream
+        }
+
+    private val reversedFileIndex = mutableMapOf<UniqIdKey, IrFile>()
+
+    private val UniqIdKey.moduleOfOrigin get() =
+        this.moduleDescriptor ?: reversedFileIndex[this]?.packageFragmentDescriptor?.containingDeclaration
+
+    private fun deserializeTopLevelDeclaration(uniqIdKey: UniqIdKey): IrDeclaration {
+        val proto = loadTopLevelDeclarationProto(uniqIdKey)
+        return deserializeDeclaration(proto, reversedFileIndex[uniqIdKey]!!)
+    }
+
+    private fun loadTopLevelDeclarationProto(uniqIdKey: UniqIdKey): IrKlibProtoBuf.IrDeclaration {
+        val file = File(irDirectory, uniqIdKey.uniqId.declarationFileName)
+        return IrKlibProtoBuf.IrDeclaration.parseFrom(file.readBytes().codedInputStream, JsKlibMetadataSerializerProtocol.extensionRegistry)
+    }
+
+    private fun findDeserializedDeclarationForDescriptor(descriptor: DeclarationDescriptor): DeclarationDescriptor? {
+        val topLevelDescriptor = descriptor.findTopLevelDescriptor()
+
+//        if (topLevelDescriptor.module.isForwardDeclarationModule) return null
+
+        if (topLevelDescriptor !is DeserializedClassDescriptor && topLevelDescriptor !is DeserializedCallableMemberDescriptor) {
+            return null
+        }
+
+        val descriptorUniqId = topLevelDescriptor.getUniqId()
+            ?: error("could not get descriptor uniq id for $topLevelDescriptor")
+        val uniqId = UniqId(descriptorUniqId.index, isLocal = false)
+        val topLevelKey = UniqIdKey(topLevelDescriptor.module, uniqId)
+
+        // This top level descriptor doesn't have a serialized IR declaration.
+        if (topLevelKey.moduleOfOrigin == null) return null
+
+        reachableTopLevels.add(topLevelKey)
+
+        do {
+            val key = reachableTopLevels.first()
+
+            if (deserializedSymbols[key]?.isBound == true ||
+                // The key.moduleOrigin is null for uniqIds that we haven't seen in any of the library headers.
+                // Just skip it for now and handle it elsewhere.
+                key.moduleOfOrigin == null) {
+
+                reachableTopLevels.remove(key)
+                deserializedTopLevels.add(key)
+                continue
+            }
+
+            deserializedModuleDescriptor = key.moduleOfOrigin
+            val reachable = deserializeTopLevelDeclaration(key)
+            reversedFileIndex[key]!!.declarations.add(reachable)
+
+            reachableTopLevels.remove(key)
+            deserializedTopLevels.add(key)
+        } while (reachableTopLevels.isNotEmpty())
+
+        return topLevelDescriptor
+    }
+
+    override fun findDeserializedDeclaration(symbol: IrSymbol): IrDeclaration? {
+
+        if (!symbol.isBound) {
+            val topLevelDesecriptor = findDeserializedDeclarationForDescriptor(symbol.descriptor)
+            if (topLevelDesecriptor == null) return null
+        }
+
+        assert(symbol.isBound) {
+            "findDeserializedDeclaration: symbol ${symbol} is unbound, descriptor = ${symbol.descriptor}, hash = ${symbol.descriptor.hashCode()}"
+        }
+
+        return symbol.owner as IrDeclaration
+    }
+
+    override fun findDeserializedDeclaration(propertyDescriptor: PropertyDescriptor): IrProperty? {
+        val topLevelDesecriptor = findDeserializedDeclarationForDescriptor(propertyDescriptor)
+        if (topLevelDesecriptor == null) return null
+
+        return symbolTable.propertyTable[propertyDescriptor]
+            ?: error("findDeserializedDeclaration: property descriptor $propertyDescriptor} is not present in propertyTable after deserialization}")
+    }
+
+    override fun declareForwardDeclarations() {
+        if (forwardModuleDescriptor == null) return
+
+        val packageFragments = forwardDeclarations.map { it.descriptor.findPackage() }.distinct()
+
+        // We don't bother making a real IR module here, as we have no need in it any later.
+        // All we need is just to declare forward declarations in the symbol table
+        // In case you need a full fledged module, turn the forEach into a map and collect
+        // produced files into an IrModuleFragment.
+
+        packageFragments.forEach { packageFragment ->
+            val symbol = IrFileSymbolImpl(packageFragment)
+            val file = IrFileImpl(NaiveSourceBasedFileEntryImpl("forward declarations pseudo-file"), symbol)
+            val symbols = forwardDeclarations
+                .filter { !it.isBound }
+                .filter { it.descriptor.findPackage() == packageFragment }
+            val declarations = symbols.map {
+
+                val classDescriptor = it.descriptor as ClassDescriptor
+                val declaration = symbolTable.declareClass(UNDEFINED_OFFSET, UNDEFINED_OFFSET, irrelevantOrigin,
+                        classDescriptor,
+                        classDescriptor.modality
+                ) { symbol: IrClassSymbol -> IrClassImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, irrelevantOrigin, symbol) }
+                declaration
+
+            }
+            file.declarations.addAll(declarations)
+        }
+    }
+
+    fun deserializeIrFile(fileProto: IrKlibProtoBuf.IrFile, moduleDescriptor: ModuleDescriptor, deserializeAllDeclarations: Boolean): IrFile {
+        val fileEntry = NaiveSourceBasedFileEntryImpl(fileProto.fileEntry.name)
+
+        // TODO: we need to store "" in protobuf, I suppose. Or better yet, reuse fqname storage from metadata.
+        val fqName = if (fileProto.fqName == "<root>") FqName.ROOT else FqName(fileProto.fqName)
+
+        val packageFragmentDescriptor = EmptyPackageFragmentDescriptor(moduleDescriptor, fqName)
+
+        val symbol = IrFileSymbolImpl(packageFragmentDescriptor)
+        val file = IrFileImpl(fileEntry, symbol, fqName)
+
+        fileProto.declarationIdList.forEach {
+            val uniqIdKey = it.uniqIdKey(moduleDescriptor)
+            reversedFileIndex.put(uniqIdKey, file)
+
+            if (deserializeAllDeclarations) {
+                file.declarations.add(deserializeTopLevelDeclaration(uniqIdKey))
+            }
+        }
+
+        return file
+    }
+
+    fun deserializeIrModule(proto: IrKlibProtoBuf.IrModule, moduleDescriptor: ModuleDescriptor, deserializeAllDeclarations: Boolean): IrModuleFragment {
+
+        deserializedModuleDescriptor = moduleDescriptor
+        deserializedModuleProtoSymbolTables.put(moduleDescriptor, proto.symbolTable)
+        deserializedModuleProtoTypeTables.put(moduleDescriptor, proto.typeTable)
+
+        var i = 0
+        val files = proto.fileList.map {
+            i++
+//            if (i >= 41)
+//                descriptorReferenceDeserializer.doCrash = true
+            deserializeIrFile(it, moduleDescriptor, deserializeAllDeclarations)
+        }
+        val module = IrModuleFragmentImpl(moduleDescriptor, builtIns, files)
+        module.patchDeclarationParents(null)
+        return module
+    }
+
+    fun deserializeIrModule(moduleDescriptor: ModuleDescriptor, byteArray: ByteArray, deserializeAllDeclarations: Boolean = false): IrModuleFragment {
+        val proto = IrKlibProtoBuf.IrModule.parseFrom(byteArray.codedInputStream, JsKlibMetadataSerializerProtocol.extensionRegistry)
+        return deserializeIrModule(proto, moduleDescriptor, deserializeAllDeclarations)
+    }
+}
@@ -0,0 +1,40 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.resolve.OverridingUtil
+
+// TODO: move me somewhere
+
+/**
+ * Implementation of given method.
+ *
+ * TODO: this method is actually a part of resolve and probably duplicates another one
+ */
+internal fun IrSimpleFunction.resolveFakeOverrideMaybeAbstract() = this.resolveFakeOverride(allowAbstract = true)
+
+internal fun IrProperty.resolveFakeOverrideMaybeAbstract() = this.getter!!.resolveFakeOverrideMaybeAbstract().correspondingProperty!!
+
+internal fun IrField.resolveFakeOverrideMaybeAbstract() = this.correspondingProperty!!.getter!!.resolveFakeOverrideMaybeAbstract().correspondingProperty!!.backingField
+
+/**
+ * Implementation of given method.
+ *
+ * TODO: this method is actually a part of resolve and probably duplicates another one
+ */
+internal fun <T : CallableMemberDescriptor> T.resolveFakeOverrideMaybeAbstract(): Set<T> {
+    if (this.kind.isReal) {
+        return setOf(this)
+    } else {
+        val overridden = OverridingUtil.getOverriddenDeclarations(this)
+        val filtered = OverridingUtil.filterOutOverridden(overridden)
+        // TODO: is it correct to take first?
+        @Suppress("UNCHECKED_CAST")
+        return filtered as Set<T>
+    }
+}
@@ -0,0 +1,12 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+class SerializedIr (
+    val module: ByteArray,
+    val declarations: Map<UniqId, ByteArray>,
+    val debugIndex: Map<UniqId, String>
+)
@@ -0,0 +1,53 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.serialization.StringTableImpl
+import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.descriptorUtil.classId
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
+import org.jetbrains.kotlin.resolve.descriptorUtil.getAllSuperClassifiers
+import org.jetbrains.kotlin.resolve.descriptorUtil.module
+import java.io.OutputStream
+
+class KonanStringTable : StringTableImpl() {
+
+    fun getClassOrPackageFqNameIndex(descriptor: ClassOrPackageFragmentDescriptor): Int {
+        when (descriptor) {
+            is PackageFragmentDescriptor -> 
+                return getPackageFqNameIndex(descriptor.fqName)
+            
+            is ClassDescriptor -> 
+                return getFqNameIndex(descriptor as ClassifierDescriptorWithTypeParameters) 
+            else -> error("Can not get fqNameIndex for $descriptor")
+        }
+    }
+
+    override fun getLocalClassIdReplacement(descriptor: ClassifierDescriptorWithTypeParameters): ClassId? {
+        return if (descriptor.containingDeclaration is CallableMemberDescriptor) {
+            val superClassifiers = descriptor.getAllSuperClassifiers()
+                .mapNotNull { it as ClassifierDescriptorWithTypeParameters }
+                .filter { it != descriptor }
+                .toList()
+            if (superClassifiers.size == 1) {
+                    superClassifiers[0].classId
+            } else {
+                val superClass = superClassifiers.find { !DescriptorUtils.isInterface(it) }
+                superClass?.classId ?: ClassId.topLevel(descriptor.module.builtIns.any.fqNameSafe)
+            }
+        } else {
+            super.getLocalClassIdReplacement(descriptor)
+        }
+    }
+
+    fun serializeTo(output: OutputStream) {
+        val (strings, qualifiedNames) = buildProto()
+        strings.writeDelimitedTo(output)
+        qualifiedNames.writeDelimitedTo(output)
+    }
+}
@@ -0,0 +1,55 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.backend.common.atMostOne
+import org.jetbrains.kotlin.backend.common.descriptors.propertyIfAccessor
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.resolve.checkers.ExpectedActualDeclarationChecker
+import org.jetbrains.kotlin.resolve.constants.StringValue
+import org.jetbrains.kotlin.utils.addToStdlib.ifNotEmpty
+
+internal val DeclarationDescriptor.isExpectMember: Boolean
+    get() = this is MemberDescriptor && this.isExpect
+
+internal val DeclarationDescriptor.isSerializableExpectClass: Boolean
+    get() = this is ClassDescriptor && ExpectedActualDeclarationChecker.shouldGenerateExpectClass(this)
+
+fun <T> AnnotationDescriptor.getArgumentValueOrNull(name: String): T? {
+    val constantValue = this.allValueArguments.entries.atMostOne {
+        it.key.asString() == name
+    }?.value
+    return constantValue?.value as T?
+}
+
+private val symbolNameAnnotation = FqName("kotlin.native.SymbolName")
+
+fun getAnnotationValue(annotation: AnnotationDescriptor): String? {
+    return annotation.allValueArguments.values.ifNotEmpty {
+        val stringValue = single() as? StringValue
+        stringValue?.value
+    }
+}
+
+fun CallableMemberDescriptor.externalSymbolOrThrow(): String? {
+    this.annotations.findAnnotation(symbolNameAnnotation)?.let {
+        return getAnnotationValue(it)!!
+    }
+
+    throw Error("external function ${this} must have @TypedIntrinsic, @SymbolName or @ObjCMethod annotation")
+}
+
+tailrec internal fun DeclarationDescriptor.findPackage(): PackageFragmentDescriptor {
+    return if (this is PackageFragmentDescriptor) this
+    else this.containingDeclaration!!.findPackage()
+}
+
+fun DeclarationDescriptor.findTopLevelDescriptor(): DeclarationDescriptor {
+    return if (this.containingDeclaration is org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor) this.propertyIfAccessor
+    else this.containingDeclaration!!.findTopLevelDescriptor()
+}
@@ -0,0 +1,108 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.resolve.descriptorUtil.classId
+
+
+class DescriptorReferenceSerializer(val declarationTable: DeclarationTable) {
+
+    // Not all exported descriptors are deserialized, some a synthesized anew during metadata deserialization.
+    // Those created descriptors can't carry the uniqIdIndex, since it is available only for deserialized descriptors.
+    // So we record the uniq id of some other "discoverable" descriptor for which we know for sure that it will be
+    // available as deserialized descriptor, plus the path to find the needed descriptor from that one.
+    fun serializeDescriptorReference(declaration: IrDeclaration): IrKlibProtoBuf.DescriptorReference? {
+
+        val descriptor = declaration.descriptor
+
+        if (!declaration.isExported() && !((declaration as? IrDeclarationWithVisibility)?.visibility == Visibilities.INVISIBLE_FAKE)) {
+            return null
+        }
+        if (declaration is IrAnonymousInitializer) return null
+
+        if (descriptor is ParameterDescriptor || (descriptor is VariableDescriptor && descriptor !is PropertyDescriptor) || descriptor is TypeParameterDescriptor) return null
+
+        val containingDeclaration = descriptor.containingDeclaration!!
+
+        val (packageFqName, classFqName) = when (containingDeclaration) {
+            is ClassDescriptor -> {
+                val classId = containingDeclaration.classId ?: return null
+                Pair(classId.packageFqName.toString(), classId.relativeClassName.toString())
+            }
+            is PackageFragmentDescriptor -> Pair(containingDeclaration.fqName.toString(), "")
+            else -> return null
+        }
+
+        val isAccessor = declaration.isAccessor
+        val isBackingField = declaration is IrField && declaration.correspondingProperty != null
+        val isFakeOverride = declaration.origin == IrDeclarationOrigin.FAKE_OVERRIDE
+        val isDefaultConstructor =
+            descriptor is ClassConstructorDescriptor && containingDeclaration is ClassDescriptor && containingDeclaration.kind == ClassKind.OBJECT
+        val isEnumEntry = descriptor is ClassDescriptor && descriptor.kind == ClassKind.ENUM_ENTRY
+        val isEnumSpecial = declaration.origin == IrDeclarationOrigin.ENUM_CLASS_SPECIAL_MEMBER
+
+
+        val realDeclaration = if (isFakeOverride) {
+            when (declaration) {
+                is IrSimpleFunction -> declaration.resolveFakeOverrideMaybeAbstract()
+                is IrField -> declaration.resolveFakeOverrideMaybeAbstract()
+                is IrProperty -> declaration.resolveFakeOverrideMaybeAbstract()
+                else -> error("Unexpected fake override declaration")
+            }
+        } else {
+            declaration
+        }
+
+        val discoverableDescriptorsDeclaration: IrDeclaration? = if (isAccessor) {
+            (realDeclaration as IrSimpleFunction).correspondingProperty!!
+        } else if (isBackingField) {
+            (realDeclaration as IrField).correspondingProperty!!
+        } else if (isDefaultConstructor || isEnumEntry) {
+            null
+        } else {
+            realDeclaration
+        }
+
+        val uniqId = discoverableDescriptorsDeclaration?.let { declarationTable.uniqIdByDeclaration(it) }
+        uniqId?.let { declarationTable.descriptors.put(discoverableDescriptorsDeclaration.descriptor, it) }
+
+        val proto = IrKlibProtoBuf.DescriptorReference.newBuilder()
+            .setPackageFqName(packageFqName)
+            .setClassFqName(classFqName)
+            .setName(descriptor.name.toString())
+
+        if (uniqId != null) proto.setUniqId(protoUniqId(uniqId))
+
+        if (isFakeOverride) {
+            proto.setIsFakeOverride(true)
+        }
+
+        if (isBackingField) {
+            proto.setIsBackingField(true)
+        }
+
+        if (isAccessor) {
+            if (declaration.isGetter)
+                proto.setIsGetter(true)
+            else if (declaration.isSetter)
+                proto.setIsSetter(true)
+            else
+                error("A property accessor which is neither a getter, nor a setter: $descriptor")
+        } else if (isDefaultConstructor) {
+            proto.setIsDefaultConstructor(true)
+        } else if (isEnumEntry) {
+            proto.setIsEnumEntry(true)
+        } else if (isEnumSpecial) {
+            proto.setIsEnumSpecial(true)
+        }
+
+        return proto.build()
+    }
+}
+
+
@@ -0,0 +1,35 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.metadata.ProtoBuf
+import org.jetbrains.kotlin.metadata.ProtoBuf.QualifiedNameTable.QualifiedName
+import org.jetbrains.kotlin.metadata.deserialization.NameResolverImpl
+import org.jetbrains.kotlin.serialization.deserialization.getClassId
+
+// TODO Come up with a better file name.
+
+internal fun NameResolverImpl.getDescriptorByFqNameIndex(
+    module: ModuleDescriptor, 
+    nameTable: ProtoBuf.QualifiedNameTable, 
+    fqNameIndex: Int): DeclarationDescriptor {
+
+    if (fqNameIndex == -1) return module.getPackage(FqName.ROOT)
+    val packageName = this.getPackageFqName(fqNameIndex)
+    // TODO: Here we are using internals of NameresolverImpl. 
+    // Consider extending NameResolver.
+    val proto = nameTable.getQualifiedName(fqNameIndex)
+    when (proto.kind!!) {
+        QualifiedName.Kind.CLASS,
+        QualifiedName.Kind.LOCAL ->
+            return module.findClassAcrossModuleDependencies(this.getClassId(fqNameIndex))!!
+        QualifiedName.Kind.PACKAGE ->
+            return module.getPackage(FqName(packageName))
+    }
+}
+
@@ -0,0 +1,57 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.ir.backend.js.lower.serialization.metadata.JsKlibMetadataProtoBuf
+import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.serialization.deserialization.descriptors.*
+import org.jetbrains.kotlin.protobuf.GeneratedMessageLite
+
+// This is an abstract uniqIdIndex any serialized IR declarations gets.
+// It is either isLocal and then just gets and ordinary number within its module.
+// Or is visible across modules and then gets a hash of mangled name as its index.
+data class UniqId (
+    val index: Long,
+    val isLocal: Boolean
+)
+
+// isLocal=true in UniqId is good while we dealing with a single current module.
+// To disambiguate module local declarations of different modules we use UniqIdKey.
+// It has moduleDescriptor specified for isLocal=true uniqIds.
+data class UniqIdKey private constructor(val uniqId: UniqId, val moduleDescriptor: ModuleDescriptor?) {
+    constructor(moduleDescriptor: ModuleDescriptor?, uniqId: UniqId)
+            : this(uniqId, if (uniqId.isLocal) moduleDescriptor!! else null)
+}
+
+internal val IrDeclaration.uniqIdIndex: Long
+    get() = this.uniqSymbolName().hashCode().toLong()
+
+fun protoUniqId(uniqId: UniqId): IrKlibProtoBuf.UniqId =
+    IrKlibProtoBuf.UniqId.newBuilder()
+       .setIndex(uniqId.index)
+       .setIsLocal(uniqId.isLocal)
+       .build()
+
+fun IrKlibProtoBuf.UniqId.uniqId(): UniqId = UniqId(this.index, this.isLocal)
+fun IrKlibProtoBuf.UniqId.uniqIdKey(moduleDescriptor: ModuleDescriptor) =
+    UniqIdKey(moduleDescriptor, this.uniqId())
+
+fun <T, M:GeneratedMessageLite.ExtendableMessage<M>> M.tryGetExtension(extension: GeneratedMessageLite.GeneratedExtension<M, T>)
+        = if (this.hasExtension(extension)) this.getExtension<T>(extension) else null
+
+fun DeclarationDescriptor.getUniqId(): JsKlibMetadataProtoBuf.DescriptorUniqId? = when (this) {
+    is DeserializedClassDescriptor              -> this.classProto.tryGetExtension(JsKlibMetadataProtoBuf.classUniqId)
+    is DeserializedSimpleFunctionDescriptor     -> this.proto.tryGetExtension(JsKlibMetadataProtoBuf.functionUniqId)
+    is DeserializedPropertyDescriptor           -> this.proto.tryGetExtension(JsKlibMetadataProtoBuf.propertyUniqId)
+    is DeserializedClassConstructorDescriptor   -> this.proto.tryGetExtension(JsKlibMetadataProtoBuf.constructorUniqId)
+    else -> null
+}
+
+fun newDescriptorUniqId(index: Long): JsKlibMetadataProtoBuf.DescriptorUniqId =
+    JsKlibMetadataProtoBuf.DescriptorUniqId.newBuilder().setIndex(index).build()
+
+val UniqId.declarationFileName: String get() = "$index${if (isLocal) "L" else "G"}.kjd"
@@ -0,0 +1,71 @@
+/*
+ * 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.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir
+
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+
+// This is a little extension over what's used in real mangling
+// since some declarations never appear in the bitcode symbols.
+
+internal fun IrDeclaration.uniqSymbolName(): String = when (this) {
+    is IrFunction
+    -> this.uniqFunctionName
+    is IrProperty
+    -> this.symbolName
+    is IrClass
+    -> this.typeInfoSymbolName
+    is IrField
+    -> this.symbolName
+    is IrEnumEntry
+    -> this.symbolName
+    else -> error("Unexpected exported declaration: $this")
+}
+
+private val IrDeclarationParent.fqNameUnique: FqName
+    get() = when(this) {
+        is IrPackageFragment -> this.fqName
+        is IrDeclaration -> this.parent.fqNameUnique.child(this.uniqName)
+        else -> error(this)
+    }
+
+private val IrDeclaration.uniqName: Name
+    get() = when (this) {
+        is IrSimpleFunction -> Name.special("<${this.uniqFunctionName}>")
+        else -> this.name
+    }
+
+private val IrProperty.symbolName: String
+    get() {
+        val extensionReceiver: String = getter!!.extensionReceiverParameter ?. extensionReceiverNamePart ?: ""
+
+        val containingDeclarationPart = parent.fqNameSafe.let {
+            if (it.isRoot) "" else "$it."
+        }
+        return "kprop:$containingDeclarationPart$extensionReceiver$name"
+    }
+
+private val IrEnumEntry.symbolName: String
+    get() {
+        val containingDeclarationPart = parent.fqNameSafe.let {
+            if (it.isRoot) "" else "$it."
+        }
+        return "kenumentry:$containingDeclarationPart$name"
+    }
+
+// This is basicly the same as .symbolName, but disambiguates external functions with the same C name.
+// In addition functions appearing in fq sequence appear as <full signature>.
+private val IrFunction.uniqFunctionName: String
+    get() {
+        val parent = this.parent
+
+        val containingDeclarationPart = parent.fqNameUnique.let {
+            if (it.isRoot) "" else "$it."
+        }
+
+        return "kfun:$containingDeclarationPart#$functionName"
+    }
@@ -0,0 +1,606 @@
+syntax = "proto2";
+package org.jetbrains.kotlin.ir.backend.js.lower.serialization.ir;
+
+option java_outer_classname = "IrKlibProtoBuf";
+option optimize_for = LITE_RUNTIME;
+
+message DescriptorReference {
+  required string package_fq_name = 1;
+  required string class_fq_name = 2;
+  required string name = 3;
+  optional UniqId uniq_id = 4;
+  optional bool is_getter = 5 [default = false];
+  optional bool is_setter = 6 [default = false];
+  optional bool is_backing_field = 7 [default = false];
+  optional bool is_fake_override = 8 [default = false];
+  optional bool is_default_constructor = 9 [default = false];
+  optional bool is_enum_entry = 10 [default = false];
+  optional bool is_enum_special = 11 [default = false];
+}
+
+message UniqId {
+  required uint64 index = 1;
+  required bool isLocal = 2;
+}
+
+message Coordinates {
+  required int32 start_offset = 1;
+  required int32 end_offset = 2;
+}
+
+/* ------ Top Level---------------------------------------------- */
+
+message IrDeclarationContainer {
+  repeated IrDeclaration declaration = 1;
+}
+
+message FileEntry { // TODO: extend me.
+                    required string name = 1;
+}
+
+message IrFile {
+  repeated UniqId declaration_id = 1;
+  required FileEntry file_entry = 2;
+  // TODO: we need a better string management. See metadata serialization as an example.
+  required string fq_name = 3;
+}
+
+message IrModule {
+  required string name = 1;
+  repeated IrFile file = 2;
+  required IrSymbolTable symbol_table = 3;
+  required IrTypeTable type_table = 4;
+}
+
+/* ------ IrSymbols --------------------------------------------- */
+
+enum IrSymbolKind {
+  FUNCTION_SYMBOL = 1;
+  CONSTRUCTOR_SYMBOL = 2;
+  ENUM_ENTRY_SYMBOL = 3;
+  FIELD_SYMBOL = 4;
+  VALUE_PARAMETER_SYMBOL = 5;
+  RETURNABLE_BLOCK_SYMBOL = 6;
+  CLASS_SYMBOL = 7;
+  TYPE_PARAMETER_SYMBOL = 8;
+  VARIABLE_SYMBOL = 9;
+  ANONYMOUS_INIT_SYMBOL = 10;
+
+  STANDALONE_FIELD_SYMBOL = 11; // For fields without properties. WrappedFieldDescriptor, rather than WrappedPropertyDescriptor.
+  RECEIVER_PARAMETER_SYMBOL = 12; // ReceiverParameterDescriptor rather than ValueParameterDescriptor.
+}
+
+message IrSymbolData {
+  required IrSymbolKind kind = 1;
+  required UniqId uniq_id = 2;
+  required UniqId top_level_uniq_id = 3;
+  optional string fqname = 4;
+  optional DescriptorReference descriptor_reference = 5;
+}
+
+message IrSymbol {
+  required int32 index = 1;
+}
+
+message IrSymbolTable {
+  repeated IrSymbolData symbols = 1;
+}
+
+/* ------ IrTypes --------------------------------------------- */
+
+enum IrTypeVariance { // Should we import metadata variance, or better stay separate?
+                      IN = 0;
+                      OUT = 1;
+                      INV = 2;
+}
+
+message Annotations {
+  repeated IrCall annotation = 1;
+}
+
+message TypeArguments {
+  repeated IrTypeIndex type_argument = 1;
+}
+
+message IrStarProjection {
+  optional bool void = 1;
+}
+
+message IrTypeProjection {
+  required IrTypeVariance variance = 1;
+  required IrTypeIndex type = 2;
+}
+
+message IrTypeArgument {
+  oneof kind {
+    IrStarProjection star = 1;
+    IrTypeProjection type = 2;
+  }
+}
+
+message IrSimpleType {
+  required Annotations annotations = 1;
+  required IrSymbol classifier = 2;
+  required bool has_question_mark = 3;
+  repeated IrTypeArgument argument = 4;
+}
+
+message IrDynamicType {
+  required Annotations annotations = 1;
+}
+
+message IrErrorType {
+  required Annotations annotations = 1;
+}
+
+message IrType {
+  oneof kind {
+    IrSimpleType simple = 1;
+    IrDynamicType dynamic = 2;
+    IrErrorType error = 3;
+  }
+}
+
+message IrTypeTable {
+  repeated IrType types = 1;
+}
+
+message IrTypeIndex {
+  required int32 index = 1;
+}
+
+/* ------ IrExpressions --------------------------------------------- */
+
+message IrBreak {
+  required int32 loop_id = 1;
+  optional string label = 2;
+}
+
+message IrBlock {
+  required bool is_lambda_origin = 1;
+  repeated IrStatement statement = 2;
+}
+
+message MemberAccessCommon {
+  optional IrExpression dispatch_receiver = 1;
+  optional IrExpression extension_receiver = 2;
+  repeated NullableIrExpression value_argument = 3;
+  required TypeArguments type_arguments = 4;
+}
+
+message IrCall {
+  enum Primitive {
+    NOT_PRIMITIVE = 1;
+    NULLARY = 2;
+    UNARY = 3;
+    BINARY = 4;
+  }
+  required Primitive kind = 1;
+  required IrSymbol symbol = 2;
+  required MemberAccessCommon member_access = 3;
+  optional IrSymbol super = 4;
+}
+
+message IrFunctionReference {
+  required IrSymbol symbol = 1;
+  optional string origin = 2;
+  required MemberAccessCommon member_access = 3;
+}
+
+
+message IrPropertyReference {
+  optional IrSymbol field = 1;
+  optional IrSymbol getter = 2;
+  optional IrSymbol setter = 3;
+  optional string origin = 4;
+  required MemberAccessCommon member_access = 5;
+}
+
+message IrComposite {
+  repeated IrStatement statement = 1;
+}
+
+message IrClassReference {
+  required IrSymbol class_symbol = 1;
+  required IrTypeIndex class_type = 2;
+}
+
+message IrConst {
+  oneof value {
+    bool null = 1;
+    bool boolean = 2;
+    int32 char = 3;
+    int32 byte = 4;
+    int32 short = 5;
+    int32 int = 6;
+    int64 long = 7;
+    float float = 8;
+    double double = 9;
+    string string = 10;
+  }
+}
+
+message IrContinue {
+  required int32 loop_id = 1;
+  optional string label = 2;
+}
+
+message IrDelegatingConstructorCall {
+  required IrSymbol symbol = 1;
+  required MemberAccessCommon member_access = 2;
+}
+
+message IrDoWhile {
+  required Loop loop = 1;
+}
+
+message IrEnumConstructorCall {
+  required IrSymbol symbol = 1;
+  required MemberAccessCommon member_access = 2;
+}
+
+message IrGetClass {
+  required IrExpression argument = 1;
+}
+
+message IrGetEnumValue {
+  required IrSymbol symbol = 2;
+}
+
+message FieldAccessCommon {
+  required IrSymbol symbol = 1;
+  optional IrSymbol super = 2;
+  optional IrExpression receiver = 3;
+}
+
+message IrGetField {
+  required FieldAccessCommon field_access = 1;
+}
+
+message IrGetValue {
+  required IrSymbol symbol = 1;
+}
+
+message IrGetObject {
+  required IrSymbol symbol = 1;
+}
+
+message IrInstanceInitializerCall {
+  required IrSymbol symbol = 1;
+}
+
+message Loop {
+  required int32 loop_id = 1;
+  required IrExpression condition = 2;
+  optional string label = 3;
+  optional IrExpression body = 4;
+}
+
+message IrReturn {
+  required IrSymbol return_target = 1;
+  required IrExpression value = 2;
+}
+
+message IrSetField {
+  required FieldAccessCommon field_access = 1;
+  required IrExpression value = 2;
+}
+
+message IrSetVariable {
+  required IrSymbol symbol = 1;
+  required IrExpression value = 2;
+}
+
+message IrSpreadElement {
+  required IrExpression expression = 1;
+  required Coordinates coordinates = 2;
+}
+
+message IrStringConcat {
+  repeated IrExpression argument = 1;
+}
+
+message IrThrow {
+  required IrExpression value = 1;
+}
+
+message IrTry {
+  required IrExpression result = 1;
+  repeated IrStatement catch = 2;
+  optional IrExpression finally = 3;
+}
+
+message IrTypeOp {
+  required IrTypeOperator operator = 1;
+  required IrTypeIndex operand = 2;
+  required IrExpression argument = 3;
+}
+
+message IrVararg {
+  required IrTypeIndex element_type = 1;
+  repeated IrVarargElement element = 2;
+}
+
+message IrVarargElement {
+  oneof vararg_element {
+    IrExpression expression = 1;
+    IrSpreadElement spread_element = 2;
+  }
+}
+
+message IrWhen {
+  repeated IrStatement branch = 1;
+}
+
+message IrWhile {
+  required Loop loop = 1;
+}
+
+// TODO: we need an extension mechanism to accomodate new
+// IR operators in upcoming releases.
+message IrOperation {
+  oneof operation {
+    IrBlock block = 1;
+    IrBreak break = 2;
+    IrCall call = 3;
+    IrClassReference class_reference = 4;
+    IrComposite composite = 5;
+    IrConst const = 6;
+    IrContinue continue = 7;
+    IrDelegatingConstructorCall delegating_constructor_call = 8;
+    IrDoWhile do_while = 9;
+    IrEnumConstructorCall enum_constructor_call = 10;
+    IrFunctionReference function_reference = 11;
+    IrGetClass get_class = 12;
+    IrGetEnumValue get_enum_value = 13;
+    IrGetField get_field = 14;
+    IrGetObject get_object = 15;
+    IrGetValue get_value = 16;
+    IrInstanceInitializerCall instance_initializer_call = 17;
+    IrPropertyReference property_reference = 18;
+    IrReturn return = 19;
+    IrSetField set_field = 20;
+    IrSetVariable set_variable = 21;
+    IrStringConcat string_concat = 22;
+    IrThrow throw = 23;
+    IrTry try = 24;
+    IrTypeOp type_op = 25;
+    IrVararg vararg = 26;
+    IrWhen when = 27;
+    IrWhile while = 28;
+  }
+}
+
+enum IrTypeOperator {
+  CAST = 1;
+  IMPLICIT_CAST = 2;
+  IMPLICIT_NOTNULL = 3;
+  IMPLICIT_COERCION_TO_UNIT = 4;
+  IMPLICIT_INTEGER_COERCION = 5;
+  SAFE_CAST = 6;
+  INSTANCEOF = 7;
+  NOT_INSTANCEOF = 8;
+  SAM_CONVERSION = 9;
+}
+
+
+message IrExpression {
+  required IrOperation operation = 1;
+  required IrTypeIndex type = 2;
+  required Coordinates coordinates = 3;
+}
+
+message NullableIrExpression {
+  optional IrExpression expression = 1;
+}
+
+/* ------ Declarations --------------------------------------------- */
+
+message IrTypeAlias {
+  // Nothing for now.
+}
+
+message IrFunction {
+  required IrSymbol symbol = 1;
+  required IrFunctionBase base = 2;
+  required ModalityKind modality = 3;
+  required bool is_tailrec = 4;
+  required bool is_suspend = 5;
+  repeated IrSymbol overridden = 6;
+  //optional UniqId corresponding_property = 7;
+}
+
+message IrFunctionBase {
+  required string name = 1;
+  required string visibility = 2;
+  required bool is_inline = 3;
+  required bool is_external = 4;
+  required IrTypeParameterContainer type_parameters = 5;
+  optional IrDeclaration dispatch_receiver = 6;
+  optional IrDeclaration extension_receiver = 7;
+  repeated IrDeclaration value_parameter = 8;
+  optional IrStatement body = 9;
+  required IrTypeIndex return_type = 10;
+}
+
+message IrConstructor {
+  required IrSymbol symbol = 1;
+  required IrFunctionBase base = 2;
+  required bool is_primary = 3;
+
+}
+
+message IrField {
+  required IrSymbol symbol = 1;
+  optional IrExpression initializer = 2;
+  required string name = 3;
+  required string visibility = 4;
+  required bool is_final = 5;
+  required bool is_external = 6;
+  required bool is_static = 7;
+  required IrTypeIndex type = 8;
+}
+
+message IrProperty {
+  optional DescriptorReference descriptor = 1; // IrProperty doesn't have a symbol at all. Preserve this rudiment for now.
+  required string name = 2;
+  required string visibility = 3;
+  required ModalityKind modality = 4;
+  required bool is_var = 5;
+  required bool is_const = 6;
+  required bool is_lateinit = 7;
+  required bool is_delegated = 8;
+  required bool is_external = 9;
+  optional IrField backing_field = 10;
+  optional IrFunction getter = 11;
+  optional IrFunction setter = 12;
+}
+
+message IrVariable {
+  required string name = 1;
+  required IrSymbol symbol = 2;
+  required IrTypeIndex type = 3;
+  required bool is_var = 4;
+  required bool is_const = 5;
+  required bool is_lateinit = 6;
+  optional IrExpression initializer = 7;
+}
+
+enum ClassKind {
+  CLASS = 1;
+  INTERFACE = 2;
+  ENUM_CLASS = 3;
+  ENUM_ENTRY = 4;
+  ANNOTATION_CLASS = 5;
+  OBJECT = 6;
+}
+
+enum ModalityKind { // It is ModalityKind to not clash with Modality in descriptor metadata.
+                    FINAL_MODALITY = 1;
+                    SEALED_MODALITY = 2;
+                    OPEN_MODALITY = 3;
+                    ABSTRACT_MODALITY = 4;
+}
+
+message IrValueParameter {
+  required IrSymbol symbol = 1;
+  required string name = 2;
+  required int32 index = 3;
+  required IrTypeIndex type = 4;
+  optional IrTypeIndex vararg_element_type = 5;
+  required bool is_crossinline = 6;
+  required bool is_noinline = 7;
+  optional IrExpression default_value = 8;
+}
+
+message IrTypeParameter {
+  required IrSymbol symbol = 1;
+  required string name = 2;
+  required int32 index = 3;
+  required IrTypeVariance variance = 4;
+  repeated IrTypeIndex super_type = 5;
+  required bool is_reified = 6;
+}
+
+message IrTypeParameterContainer {
+  repeated IrDeclaration type_parameter = 1;
+}
+
+message IrClass {
+  required IrSymbol symbol = 1;
+  required string name = 2;
+  required ClassKind kind = 3;
+  required string visibility = 4;
+  required ModalityKind modality = 5;
+  // TODO: consider using flags for the booleans.
+  required bool is_companion = 6;
+  required bool is_inner = 7;
+  required bool is_data = 8;
+  required bool is_external = 9;
+  required bool is_inline = 10;
+  optional IrDeclaration this_receiver = 11;
+  required IrTypeParameterContainer type_parameters = 12;
+  required IrDeclarationContainer declaration_container = 13;
+  repeated IrTypeIndex super_type = 14;
+}
+
+message IrEnumEntry {
+  required IrSymbol symbol = 1;
+  optional IrExpression initializer = 2;
+  optional IrDeclaration corresponding_class = 3;
+  required string name = 4;
+}
+
+message IrAnonymousInit {
+  required IrSymbol symbol = 1;
+  required IrStatement body = 2;
+}
+
+// TODO: we need an extension mechanism to accomodate new
+// IR operators in upcoming releases.
+message IrDeclarator {
+  oneof declarator {
+    IrAnonymousInit ir_anonymous_init = 1;
+    IrClass ir_class = 2;
+    IrConstructor ir_constructor = 3;
+    IrEnumEntry ir_enum_entry = 4;
+    IrField ir_field = 5;
+    IrFunction ir_function = 6;
+    IrProperty ir_property = 7;
+    IrTypeAlias ir_type_alias = 8;
+    IrTypeParameter ir_type_parameter = 9;
+    IrVariable ir_variable = 10;
+    IrValueParameter ir_value_parameter = 11;
+  }
+}
+
+message IrDeclarationOrigin {
+  required string name = 1;
+}
+
+message IrDeclaration {
+  required IrDeclarationOrigin origin = 1;
+  required Coordinates coordinates = 2;
+  required Annotations annotations = 3;
+  required IrDeclarator declarator = 4;
+  //repeated IrDeclaration nested = 5;
+  required string file_name = 5; // TODO: files should be communicated some other way, I suppose.
+}
+
+/* ------- IrStatements --------------------------------------------- */
+
+message IrBranch {
+  required IrExpression condition = 1;
+  required IrExpression result = 2;
+}
+
+message IrBlockBody {
+  repeated IrStatement statement = 1;
+}
+
+message IrCatch {
+  required IrDeclaration catch_parameter = 1;
+  required IrExpression result = 2;
+}
+
+enum IrSyntheticBodyKind {
+  ENUM_VALUES = 1;
+  ENUM_VALUEOF = 2;
+}
+
+message IrSyntheticBody {
+  required IrSyntheticBodyKind kind = 1;
+}
+
+// Let's try to map IrElement as well as IrStatement to IrStatement.
+message IrStatement {
+  required Coordinates coordinates = 1;
+  oneof statement {
+    IrDeclaration declaration = 2;
+    IrExpression expression = 3;
+    IrBlockBody block_body = 4;
+    IrBranch branch = 5;
+    IrCatch catch = 6;
+    IrSyntheticBody synthetic_body = 7;
+  }
+}
@@ -64,7 +64,7 @@ fun createJsKlibMetadataPackageFragmentProvider(
        emptyList(),
        notFoundClasses,
        ContractDeserializerImpl(configuration, storageManager),
-        platformDependentDeclarationFilter = PlatformDependentDeclarationFilter.NoPlatformDependent,
+        platformDependentDeclarationFilter = PlatformDependentDeclarationFilter.All,
        extensionRegistryLite = JsKlibMetadataSerializerProtocol.extensionRegistry
    )

@@ -5,6 +5,7 @@

 package org.jetbrains.kotlin.ir.backend.js.transformers.irToJs

+import org.jetbrains.kotlin.backend.common.ir.isElseBranch
 import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.lower.coroutines.COROUTINE_SWITCH
 import org.jetbrains.kotlin.ir.backend.js.utils.JsGenerationContext
@@ -99,7 +100,7 @@ class IrElementToJsStatementTransformer : BaseIrElementToJsNodeTransformer<JsSta
        var expr: IrExpression? = null
        val cases = expression.branches.map {
            val body = it.result
-            val id = if (it is IrElseBranch) null else {
+            val id = if (isElseBranch(it)) null else {
                val call = it.condition as IrCall
                expr = call.getValueArgument(0) as IrExpression
                call.getValueArgument(1)
@@ -102,8 +102,10 @@ class JsClassGenerator(private val irClass: IrClass, val context: JsGenerationCo
    private fun generateThrowableProperties(): List<JsStatement> {
        val functions = irClass.declarations.filterIsInstance<IrSimpleFunction>()

-        val messageGetter = functions.single { it.name == Name.special("<get-message>") }
-        val causeGetter = functions.single { it.name == Name.special("<get-cause>") }
+
+        // TODO: Fix `Name.special` deserialization
+        val messageGetter = functions.single { it.name.asString() == "<get-message>" }
+        val causeGetter = functions.single { it.name.asString() == "<get-cause>" }

        val msgProperty = defineProperty(classPrototypeRef, "message", getter = buildGetterFunction(messageGetter))

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.ir.backend.js.transformers.irToJs

 import org.jetbrains.kotlin.backend.common.descriptors.isSuspend
+import org.jetbrains.kotlin.backend.common.ir.isElseBranch
 import org.jetbrains.kotlin.ir.backend.js.utils.JsGenerationContext
 import org.jetbrains.kotlin.ir.backend.js.utils.Namer
 import org.jetbrains.kotlin.ir.declarations.IrFunction
@@ -24,7 +25,7 @@ fun <T : JsNode, D : JsGenerationContext> IrWhen.toJsNode(
 ): T? =
    branches.foldRight<IrBranch, T?>(null) { br, n ->
        val body = br.result.accept(tr, data)
-        if (br is IrElseBranch) body
+        if (isElseBranch(br)) body
        else {
            val condition = br.condition.accept(IrElementToJsExpressionTransformer(), data)
            node(condition, body, n)
@@ -99,4 +99,6 @@ object Namer {

    val THIS_SPECIAL_NAME = "<this>"
    val SET_SPECIAL_NAME = "<set-?>"
+
+    val DYNAMIC_FILE_NAME = "<dynamicDeclarations>"
 }
@@ -64,6 +64,7 @@ abstract class IrLazyDeclarationBase(
            }
            is ClassDescriptor -> stubGenerator.generateClassStub(containingDeclaration)
            is FunctionDescriptor -> stubGenerator.generateFunctionStub(containingDeclaration)
+            is PropertyDescriptor -> stubGenerator.generateFunctionStub(containingDeclaration.run { getter ?: setter!! })
            else -> throw AssertionError("Package or class expected: $containingDeclaration; for $currentDescriptor")
        }
    }
@@ -15,6 +15,12 @@ import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
+import org.jetbrains.kotlin.ir.types.IrSimpleType
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
+import org.jetbrains.kotlin.ir.types.IrSimpleType
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
 import org.jetbrains.kotlin.ir.types.withHasQuestionMark
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.SymbolTable
@@ -72,68 +78,97 @@ class IrBuiltIns(
    private fun List<SimpleType>.defineComparisonOperatorForEachType(name: String) =
        associate { it to defineComparisonOperator(name, it) }

+    private class IrTypeMapper(val type: () -> IrType, val nType: () -> IrType)
+
+    private fun buildNullableType(irType: IrType) = with(irType as IrSimpleType) {
+        IrSimpleTypeImpl(classifier, true, arguments, annotations)
+    }
+
+    private val primitiveTypesLazyMapping = mapOf<ClassifierDescriptor, IrTypeMapper>(
+        builtIns.any to IrTypeMapper({ anyType }, { anyNType }),
+        builtIns.boolean to IrTypeMapper({ booleanType }, { buildNullableType(booleanType) }),
+        builtIns.char to IrTypeMapper({ charType }, { buildNullableType(charType) }),
+        builtIns.number to IrTypeMapper({ numberType }, { buildNullableType(numberType) }),
+        builtIns.byte to IrTypeMapper({ byteType }, { buildNullableType(byteType) }),
+        builtIns.short to IrTypeMapper({ shortType }, { buildNullableType(shortType) }),
+        builtIns.int to IrTypeMapper({ intType }, { buildNullableType(intType) }),
+        builtIns.long to IrTypeMapper({ longType }, { buildNullableType(longType) }),
+        builtIns.float to IrTypeMapper({ floatType }, { buildNullableType(floatType) }),
+        builtIns.double to IrTypeMapper({ doubleType }, { buildNullableType(doubleType) }),
+        builtIns.nothing to IrTypeMapper({ nothingType }, { nothingNType }),
+        builtIns.unit to IrTypeMapper({ unitType }, { buildNullableType(unitType) }),
+        builtIns.string to IrTypeMapper({ stringType }, { buildNullableType(stringType) }),
+        builtIns.throwable to IrTypeMapper({ throwableType }, { buildNullableType(throwableType) })
+//        builtIns.array to { arrayClass.owner.defaultType }
+    )
+
+    fun getPrimitiveTypeOrNullByDescriptor(descriptor: ClassifierDescriptor, isNullable: Boolean) =
+        primitiveTypesLazyMapping[descriptor]?.let {
+            if (isNullable) it.nType() else it.type()
+        } as IrSimpleType?
+
    val any = builtIns.anyType
    val anyN = builtIns.nullableAnyType
-    val anyType = any.toIrType()
-    val anyClass = builtIns.any.toIrSymbol()
-    val anyNType = anyType.withHasQuestionMark(true)
+    val anyType by lazy { any.toIrType() }
+    val anyClass by lazy { builtIns.any.toIrSymbol() }
+    val anyNType by lazy { anyType.withHasQuestionMark(true) }

    val bool = builtIns.booleanType
-    val booleanType = bool.toIrType()
-    val booleanClass = builtIns.boolean.toIrSymbol()
+    val booleanType by lazy { bool.toIrType() }
+    val booleanClass by lazy { builtIns.boolean.toIrSymbol() }

    val char = builtIns.charType
-    val charType = char.toIrType()
-    val charClass = builtIns.char.toIrSymbol()
+    val charType by lazy { char.toIrType() }
+    val charClass by lazy { builtIns.char.toIrSymbol() }

    val number = builtIns.number.defaultType
-    val numberType = number.toIrType()
-    val numberClass = builtIns.number.toIrSymbol()
+    val numberType by lazy { number.toIrType() }
+    val numberClass by lazy { builtIns.number.toIrSymbol() }

    val byte = builtIns.byteType
-    val byteType = byte.toIrType()
-    val byteClass = builtIns.byte.toIrSymbol()
+    val byteType by lazy { byte.toIrType() }
+    val byteClass by lazy { builtIns.byte.toIrSymbol() }

    val short = builtIns.shortType
-    val shortType = short.toIrType()
-    val shortClass = builtIns.short.toIrSymbol()
+    val shortType by lazy { short.toIrType() }
+    val shortClass by lazy { builtIns.short.toIrSymbol() }

    val int = builtIns.intType
-    val intType = int.toIrType()
-    val intClass = builtIns.int.toIrSymbol()
+    val intType by lazy { int.toIrType() }
+    val intClass by lazy { builtIns.int.toIrSymbol() }

    val long = builtIns.longType
-    val longType = long.toIrType()
-    val longClass = builtIns.long.toIrSymbol()
+    val longType by lazy { long.toIrType() }
+    val longClass by lazy { builtIns.long.toIrSymbol() }

    val float = builtIns.floatType
-    val floatType = float.toIrType()
-    val floatClass = builtIns.float.toIrSymbol()
+    val floatType by lazy { float.toIrType() }
+    val floatClass by lazy { builtIns.float.toIrSymbol() }

    val double = builtIns.doubleType
-    val doubleType = double.toIrType()
-    val doubleClass = builtIns.double.toIrSymbol()
+    val doubleType by lazy { double.toIrType() }
+    val doubleClass by lazy { builtIns.double.toIrSymbol() }

    val nothing = builtIns.nothingType
    val nothingN = builtIns.nullableNothingType
-    val nothingType = nothing.toIrType()
-    val nothingClass = builtIns.nothing.toIrSymbol()
-    val nothingNType = nothingType.withHasQuestionMark(true)
+    val nothingType by lazy { nothing.toIrType() }
+    val nothingClass by lazy { builtIns.nothing.toIrSymbol() }
+    val nothingNType by lazy { nothingType.withHasQuestionMark(true) }

    val unit = builtIns.unitType
-    val unitType = unit.toIrType()
-    val unitClass = builtIns.unit.toIrSymbol()
+    val unitType by lazy { unit.toIrType() }
+    val unitClass by lazy { builtIns.unit.toIrSymbol() }

    val string = builtIns.stringType
-    val stringType = string.toIrType()
-    val stringClass = builtIns.string.toIrSymbol()
+    val stringType by lazy { string.toIrType() }
+    val stringClass by lazy { builtIns.string.toIrSymbol() }

-    val collectionClass = builtIns.collection.toIrSymbol()
+    val collectionClass by lazy { builtIns.collection.toIrSymbol() }

-    val arrayClass = builtIns.array.toIrSymbol()
+    val arrayClass by lazy { builtIns.array.toIrSymbol() }

-    val throwableType = builtIns.throwable.defaultType.toIrType()
-    val throwableClass = builtIns.throwable.toIrSymbol()
+    val throwableType by lazy { builtIns.throwable.defaultType.toIrType() }
+    val throwableClass by lazy { builtIns.throwable.toIrSymbol() }

    val kCallableClass = builtIns.getBuiltInClassByFqName(KotlinBuiltIns.FQ_NAMES.kCallable.toSafe()).toIrSymbol()
    val kPropertyClass = builtIns.getBuiltInClassByFqName(KotlinBuiltIns.FQ_NAMES.kPropertyFqName.toSafe()).toIrSymbol()
@@ -5,9 +5,11 @@

 package org.jetbrains.kotlin.ir.types

+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ClassifierDescriptor
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
+import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrTypeParameter
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
@@ -68,6 +70,8 @@ fun IrType.makeNullable(addKotlinType:Boolean = true) =
    else
        this

+var irTypeKotlinBuiltIns: KotlinBuiltIns? = null
+
 fun IrType.toKotlinType(): KotlinType {
    originalKotlinType?.let {
        return it
@@ -75,6 +79,7 @@ fun IrType.toKotlinType(): KotlinType {

    return when (this) {
        is IrSimpleType -> makeKotlinType(classifier, arguments, hasQuestionMark)
+        is IrDynamicType -> createDynamicType(irTypeKotlinBuiltIns!!)
        else -> TODO(toString())
    }
 }
@@ -21,16 +21,21 @@ import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
+import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.declarations.impl.IrPropertyImpl
 import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.declarations.lazy.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrErrorExpressionImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
+import org.jetbrains.kotlin.ir.symbols.impl.IrValueParameterSymbolImpl
+import org.jetbrains.kotlin.ir.types.impl.IrDynamicTypeImpl
 import org.jetbrains.kotlin.load.java.descriptors.JavaCallableMemberDescriptor
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.hasBackingField
 import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.Variance
+import org.jetbrains.kotlin.types.isDynamic

 class DeclarationStubGenerator(
    moduleDescriptor: ModuleDescriptor,
@@ -58,7 +58,8 @@ val PROTO_PATHS: List<ProtoPath> = listOf(
        ProtoPath("core/metadata.jvm/src/jvm_metadata.proto"),
        ProtoPath("core/metadata.jvm/src/jvm_module.proto"),
        ProtoPath("build-common/src/java_descriptors.proto"),
-        ProtoPath("compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/metadata/js.proto")
+//        ProtoPath("compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/metadata/js.proto"),
+        ProtoPath("compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/ir.proto")
 )

 private val EXT_OPTIONS_PROTO_PATH = ProtoPath("core/metadata/src/ext_options.proto")
@@ -15,6 +15,7 @@ import org.jetbrains.kotlin.config.*
 import org.jetbrains.kotlin.ir.backend.js.compile
 import org.jetbrains.kotlin.js.test.JsIrTestRuntime
 import org.jetbrains.kotlin.psi.KtFile
+import org.jetbrains.kotlin.test.KotlinTestUtils
 import java.io.File

 fun buildConfiguration(environment: KotlinCoreEnvironment): CompilerConfiguration {
@@ -38,6 +39,8 @@ fun buildConfiguration(environment: KotlinCoreEnvironment): CompilerConfiguratio

 private val stdKlibFile = File("js/js.translator/testData/out/klibs/stdlib.klib")

+private val resultJs = "js/js.translator/testData/out/klibs/result.js"
+
 fun main() {

    val environment = KotlinCoreEnvironment.createForTests(Disposable { }, CompilerConfiguration(), EnvironmentConfigFiles.JS_CONFIG_FILES)
@@ -53,7 +56,7 @@ fun main() {

    val result = compile(
        environment.project,
-        JsIrTestRuntime.FULL.sources.map(::createPsiFile),
+        (JsIrTestRuntime.FULL.sources).map(::createPsiFile),
        buildConfiguration(environment),
        null,
        true,
@@ -61,5 +64,7 @@ fun main() {
        emptyList()
    )

-    TODO("Write library into $stdKlibFile")
+    File(resultJs).writeText(result.generatedCode)
+
+//    TODO("Write library into $stdKlibFile")
 }