Refactor entire IrInterpreter to achieve better code quality

2021-03-17 19:59:53 +03:00
parent 3294af5e49
commit c8b268a789
20 changed files with 1459 additions and 1085 deletions
@@ -0,0 +1,436 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.ir.interpreter
+
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrConstructorCallImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrGetObjectValueImpl
+import org.jetbrains.kotlin.ir.interpreter.builtins.evaluateIntrinsicAnnotation
+import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterError
+import org.jetbrains.kotlin.ir.interpreter.stack.CallStack
+import org.jetbrains.kotlin.ir.interpreter.stack.Variable
+import org.jetbrains.kotlin.ir.interpreter.state.*
+import org.jetbrains.kotlin.ir.types.classOrNull
+import org.jetbrains.kotlin.ir.types.classifierOrNull
+import org.jetbrains.kotlin.ir.util.*
+import org.jetbrains.kotlin.ir.util.hasAnnotation
+
+internal fun unfoldInstruction(element: IrElement?, environment: IrInterpreterEnvironment) {
+    val callStack = environment.callStack
+    when (element) {
+        null -> return
+        is IrSimpleFunction -> unfoldFunction(element, environment)
+        is IrConstructor -> unfoldConstructor(element, callStack)
+        is IrCall -> unfoldCall(element, callStack)
+        is IrConstructorCall -> unfoldConstructorCall(element, callStack)
+        is IrEnumConstructorCall -> unfoldEnumConstructorCall(element, callStack)
+        is IrDelegatingConstructorCall -> unfoldDelegatingConstructorCall(element, callStack)
+        is IrInstanceInitializerCall -> unfoldInstanceInitializerCall(element, callStack)
+        is IrField -> unfoldField(element, callStack)
+        is IrBody -> unfoldBody(element, callStack)
+        is IrBlock -> unfoldBlock(element, callStack)
+        is IrReturn -> unfoldReturn(element, callStack)
+        is IrSetField -> unfoldSetField(element, callStack)
+        is IrGetField -> callStack.addInstruction(SimpleInstruction(element))
+        is IrGetValue -> unfoldGetValue(element, environment)
+        is IrGetObjectValue -> unfoldGetObjectValue(element, environment)
+        is IrGetEnumValue -> unfoldGetEnumValue(element, environment)
+        is IrEnumEntry -> unfoldEnumEntry(element, environment)
+        is IrConst<*> -> callStack.addInstruction(SimpleInstruction(element))
+        is IrVariable -> unfoldVariable(element, callStack)
+        is IrSetValue -> unfoldSetValue(element, callStack)
+        is IrTypeOperatorCall -> unfoldTypeOperatorCall(element, callStack)
+        is IrBranch -> unfoldBranch(element, callStack)
+        is IrWhileLoop -> unfoldWhileLoop(element, callStack)
+        is IrDoWhileLoop -> unfoldDoWhileLoop(element, callStack)
+        is IrWhen -> unfoldWhen(element, callStack)
+        is IrBreak -> unfoldBreak(element, callStack)
+        is IrContinue -> unfoldContinue(element, callStack)
+        is IrVararg -> unfoldVararg(element, callStack)
+        is IrSpreadElement -> callStack.addInstruction(CompoundInstruction(element.expression))
+        is IrTry -> unfoldTry(element, callStack)
+        is IrCatch -> unfoldCatch(element, callStack)
+        is IrThrow -> unfoldThrow(element, callStack)
+        is IrStringConcatenation -> unfoldStringConcatenation(element, environment)
+        is IrFunctionExpression -> callStack.addInstruction(SimpleInstruction(element))
+        is IrFunctionReference -> unfoldFunctionReference(element, callStack)
+        is IrPropertyReference -> unfoldPropertyReference(element, callStack)
+        is IrClassReference -> unfoldClassReference(element, callStack)
+        is IrComposite -> unfoldComposite(element, callStack)
+
+        else -> TODO("${element.javaClass} not supported")
+    }
+}
+
+private fun unfoldFunction(function: IrSimpleFunction, environment: IrInterpreterEnvironment) {
+    if (environment.callStack.getStackCount() >= IrInterpreterEnvironment.MAX_STACK)
+        return StackOverflowError().handleUserException(environment)
+    // SimpleInstruction with function is added in IrCall
+    // It will serve as endpoint for all possible calls, there we drop frame and copy result to new one
+    function.body?.let { environment.callStack.addInstruction(CompoundInstruction(it)) }
+        ?: throw InterpreterError("Ir function must be with body")
+}
+
+private fun unfoldConstructor(constructor: IrConstructor, callStack: CallStack) {
+    // SimpleInstruction with function is added in constructor call
+    // It will serve as endpoint for all possible constructor calls, there we drop frame and return object
+    callStack.addInstruction(CompoundInstruction(constructor.body!!))
+}
+
+private fun unfoldCall(call: IrCall, callStack: CallStack) {
+    val function = call.symbol.owner
+    // new sub frame is used to store value arguments, in case then they are used in default args evaluation
+    callStack.newSubFrame(call, listOf())
+    callStack.addInstruction(SimpleInstruction(call))
+    unfoldValueParameters(call, callStack)
+
+    // must save receivers in memory in case then they are used in default args evaluation
+    call.extensionReceiver?.let {
+        callStack.addInstruction(SimpleInstruction(function.extensionReceiverParameter!!))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+    call.dispatchReceiver?.let {
+        callStack.addInstruction(SimpleInstruction(function.dispatchReceiverParameter!!))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+}
+
+private fun unfoldConstructorCall(constructorCall: IrFunctionAccessExpression, callStack: CallStack) {
+    val constructor = constructorCall.symbol.owner
+    callStack.newSubFrame(constructorCall, listOf()) // used to store value arguments, in case then they are use as default args
+    // this variable is used to create object once
+    callStack.addVariable(Variable(constructorCall.getThisReceiver(), Common(constructor.parentAsClass)))
+    callStack.addInstruction(SimpleInstruction(constructorCall))
+    unfoldValueParameters(constructorCall, callStack)
+
+    constructorCall.dispatchReceiver?.let {
+        callStack.addInstruction(SimpleInstruction(constructor.dispatchReceiverParameter!!))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+}
+
+private fun unfoldEnumConstructorCall(enumConstructorCall: IrEnumConstructorCall, callStack: CallStack) {
+    callStack.newSubFrame(enumConstructorCall, listOf()) // used to store value arguments, in case then they are use as default args
+    callStack.addInstruction(SimpleInstruction(enumConstructorCall))
+    unfoldValueParameters(enumConstructorCall, callStack)
+}
+
+private fun unfoldDelegatingConstructorCall(delegatingConstructorCall: IrFunctionAccessExpression, callStack: CallStack) {
+    callStack.newSubFrame(delegatingConstructorCall, listOf()) // used to store value arguments, in case then they are use as default args
+    callStack.addInstruction(SimpleInstruction(delegatingConstructorCall))
+    unfoldValueParameters(delegatingConstructorCall, callStack)
+}
+
+private fun unfoldValueParameters(expression: IrFunctionAccessExpression, callStack: CallStack) {
+    fun IrValueParameter.getDefault(): IrExpressionBody? {
+        return defaultValue
+            ?: (this.parent as? IrSimpleFunction)?.overriddenSymbols
+                ?.map { it.owner.valueParameters[this.index].getDefault() }
+                ?.firstNotNullOfOrNull { it }
+    }
+
+    fun getDefaultForParameterAt(index: Int): IrExpression? {
+        return expression.symbol.owner.valueParameters[index].getDefault()?.expression
+    }
+
+    val irFunction = expression.symbol.owner
+    val valueParametersSymbols = irFunction.valueParameters.map { it.symbol }
+    val valueArguments = (0 until expression.valueArgumentsCount).map { expression.getValueArgument(it) }
+
+    for (i in valueParametersSymbols.indices.reversed()) {
+        callStack.addInstruction(SimpleInstruction(valueParametersSymbols[i].owner))
+        val arg = valueArguments[i] ?: getDefaultForParameterAt(i)
+        when {
+            arg != null -> callStack.addInstruction(CompoundInstruction(arg))
+            else ->
+                // case when value parameter is vararg and it is missing
+                expression.getVarargType(i)?.let {
+                    callStack.addInstruction(SimpleInstruction(IrConstImpl.constNull(UNDEFINED_OFFSET, UNDEFINED_OFFSET, it)))
+                }
+        }
+    }
+
+    // hack for extension receiver in lambda
+    if (expression.valueArgumentsCount != irFunction.valueParameters.size) {
+        val extensionReceiver = irFunction.getExtensionReceiver() ?: return
+        callStack.addInstruction(SimpleInstruction(extensionReceiver.owner))
+        valueArguments[0]?.let { callStack.addInstruction(CompoundInstruction(it)) }
+    }
+}
+
+private fun unfoldInstanceInitializerCall(instanceInitializerCall: IrInstanceInitializerCall, callStack: CallStack) {
+    val irClass = instanceInitializerCall.classSymbol.owner
+
+    // init blocks processing
+    val anonymousInitializer = irClass.declarations.filterIsInstance<IrAnonymousInitializer>().filter { !it.isStatic }
+    anonymousInitializer.reversed().forEach { callStack.addInstruction(CompoundInstruction(it.body)) }
+
+    // properties processing
+    val classProperties = irClass.declarations.filterIsInstance<IrProperty>()
+    classProperties.filter { it.backingField?.initializer?.expression != null }.reversed()
+        .forEach { callStack.addInstruction(CompoundInstruction(it.backingField)) }
+}
+
+private fun unfoldField(field: IrField, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(field))
+    callStack.addInstruction(CompoundInstruction(field.initializer?.expression))
+}
+
+private fun unfoldBody(body: IrBody, callStack: CallStack) {
+    unfoldStatements(body.statements, callStack)
+}
+
+private fun unfoldBlock(block: IrBlock, callStack: CallStack) {
+    callStack.newSubFrame(block, listOf())
+    callStack.addInstruction(SimpleInstruction(block))
+    unfoldStatements(block.statements, callStack)
+}
+
+private fun unfoldStatements(statements: List<IrStatement>, callStack: CallStack) {
+    for (i in statements.indices.reversed()) {
+        when (val statement = statements[i]) {
+            is IrClass -> if (!statement.isLocal) TODO("Only local classes are supported")
+            is IrFunction -> if (!statement.isLocal) TODO("Only local functions are supported")
+            else -> callStack.addInstruction(CompoundInstruction(statement))
+        }
+    }
+}
+
+private fun unfoldReturn(expression: IrReturn, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(expression)) //2
+    callStack.addInstruction(CompoundInstruction(expression.value)) //1
+}
+
+private fun unfoldSetField(expression: IrSetField, callStack: CallStack) {
+    // receiver is null, for example, for top level fields; cannot interpret set on top level var
+    if (expression.receiver.let { it == null || (it.type.classifierOrNull?.owner as? IrClass)?.isObject == true }) {
+        error("Cannot interpret set method on top level properties")
+    }
+
+    callStack.addInstruction(SimpleInstruction(expression))
+    callStack.addInstruction(CompoundInstruction(expression.value))
+}
+
+private fun unfoldGetValue(expression: IrGetValue, environment: IrInterpreterEnvironment) {
+    val expectedClass = expression.type.classOrNull?.owner
+    // used to evaluate constants inside object
+    if (expectedClass != null && expectedClass.isObject && expression.symbol.owner.origin == IrDeclarationOrigin.INSTANCE_RECEIVER) {
+        // TODO is this correct behaviour?
+        return unfoldGetObjectValue(IrGetObjectValueImpl(0, 0, expectedClass.defaultType, expectedClass.symbol), environment)
+    }
+    environment.callStack.pushState(environment.callStack.getVariable(expression.symbol).state)
+}
+
+private fun unfoldGetObjectValue(expression: IrGetObjectValue, environment: IrInterpreterEnvironment) {
+    val callStack = environment.callStack
+    val objectClass = expression.symbol.owner
+    environment.mapOfObjects[objectClass.symbol]?.let { return callStack.pushState(it) }
+
+    callStack.newSubFrame(expression, listOf(SimpleInstruction(expression)))
+    when {
+        !objectClass.hasAnnotation(evaluateIntrinsicAnnotation) -> {
+            val state = Common(objectClass)
+            environment.mapOfObjects[objectClass.symbol] = state  // must set object's state here to avoid cyclic evaluation
+            callStack.addVariable(Variable(objectClass.thisReceiver!!.symbol, state))
+
+            val constructor = objectClass.constructors.first()
+            val constructorCall = IrConstructorCallImpl.fromSymbolOwner(constructor.returnType, constructor.symbol)
+            callStack.addInstruction(CompoundInstruction(constructorCall))
+        }
+    }
+}
+
+private fun unfoldGetEnumValue(expression: IrGetEnumValue, environment: IrInterpreterEnvironment) {
+    val callStack = environment.callStack
+    environment.mapOfEnums[expression.symbol]?.let { return callStack.pushState(it) }
+
+    callStack.addInstruction(SimpleInstruction(expression))
+    val enumEntry = expression.symbol.owner
+    val enumClass = enumEntry.symbol.owner.parentAsClass
+    enumClass.declarations.filterIsInstance<IrEnumEntry>().forEach {
+        if (enumClass.hasAnnotation(evaluateIntrinsicAnnotation)) return@forEach callStack.addInstruction(SimpleInstruction(it))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+}
+
+private fun unfoldEnumEntry(enumEntry: IrEnumEntry, environment: IrInterpreterEnvironment) {
+    val enumClass = enumEntry.symbol.owner.parentAsClass
+    val enumEntries = enumClass.declarations.filterIsInstance<IrEnumEntry>()
+
+    val enumSuperCall = (enumClass.primaryConstructor?.body?.statements?.firstOrNull() as? IrEnumConstructorCall)
+    if (enumEntries.isNotEmpty() && enumSuperCall != null) {
+        val valueArguments = listOf(
+            enumEntry.name.asString().toIrConst(environment.irBuiltIns.stringType),
+            enumEntries.indexOf(enumEntry).toIrConst(environment.irBuiltIns.intType)
+        )
+        valueArguments.forEachIndexed { index, irConst -> enumSuperCall.putValueArgument(index, irConst) }
+    }
+
+    val enumConstructorCall = enumEntry.initializerExpression?.expression as? IrEnumConstructorCall
+        ?: throw InterpreterError("Initializer at enum entry ${enumEntry.fqNameWhenAvailable} is null")
+    val enumClassObject = Variable(enumConstructorCall.getThisReceiver(), Common(enumEntry.correspondingClass ?: enumClass))
+    environment.mapOfEnums[enumEntry.symbol] = enumClassObject.state as Complex
+
+    environment.callStack.newSubFrame(enumEntry, listOf(CompoundInstruction(enumConstructorCall), SimpleInstruction(enumEntry)))
+    environment.callStack.addVariable(enumClassObject)
+}
+
+private fun unfoldVariable(variable: IrVariable, callStack: CallStack) {
+    when (variable.initializer) {
+        null -> callStack.addVariable(Variable(variable.symbol))
+        else -> {
+            callStack.addInstruction(SimpleInstruction(variable))
+            callStack.addInstruction(CompoundInstruction(variable.initializer!!))
+        }
+    }
+}
+
+private fun unfoldSetValue(expression: IrSetValue, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(expression))
+    callStack.addInstruction(CompoundInstruction(expression.value))
+}
+
+private fun unfoldTypeOperatorCall(element: IrTypeOperatorCall, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(element))
+    callStack.addInstruction(CompoundInstruction(element.argument))
+}
+
+private fun unfoldBranch(branch: IrBranch, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(branch)) //2
+    callStack.addInstruction(CompoundInstruction(branch.condition)) //1
+}
+
+private fun unfoldWhileLoop(loop: IrWhileLoop, callStack: CallStack) {
+    callStack.newSubFrame(loop, listOf())
+    callStack.addInstruction(SimpleInstruction(loop))
+    callStack.addInstruction(CompoundInstruction(loop.condition))
+}
+
+private fun unfoldDoWhileLoop(loop: IrDoWhileLoop, callStack: CallStack) {
+    callStack.newSubFrame(loop, listOf())
+    callStack.addInstruction(SimpleInstruction(loop))
+    callStack.addInstruction(CompoundInstruction(loop.condition))
+    callStack.addInstruction(CompoundInstruction(loop.body))
+}
+
+private fun unfoldWhen(element: IrWhen, callStack: CallStack) {
+    // new sub frame to drop it after
+    callStack.newSubFrame(element, element.branches.map { CompoundInstruction(it) } + listOf(SimpleInstruction(element)))
+}
+
+private fun unfoldContinue(element: IrContinue, callStack: CallStack) {
+    callStack.unrollInstructionsForBreakContinue(element)
+}
+
+private fun unfoldBreak(element: IrBreak, callStack: CallStack) {
+    callStack.unrollInstructionsForBreakContinue(element)
+}
+
+private fun unfoldVararg(element: IrVararg, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(element))
+    element.elements.reversed().forEach { callStack.addInstruction(CompoundInstruction(it)) }
+}
+
+private fun unfoldTry(element: IrTry, callStack: CallStack) {
+    callStack.newSubFrame(element, listOf())
+    callStack.addInstruction(SimpleInstruction(element))
+    callStack.addInstruction(CompoundInstruction(element.tryResult))
+}
+
+private fun unfoldCatch(element: IrCatch, callStack: CallStack) {
+    val exceptionState = callStack.peekState() as? ExceptionState ?: return
+    if (exceptionState.isSubtypeOf(element.catchParameter.type)) {
+        callStack.popState()
+        val frameOwner = callStack.getCurrentFrameOwner() as IrTry
+        callStack.dropSubFrame() // drop other catch blocks
+        callStack.newSubFrame(element, listOf()) // new frame with IrTry instruction to interpret finally block at the end
+        callStack.addVariable(Variable(element.catchParameter.symbol, exceptionState))
+        callStack.addInstruction(SimpleInstruction(frameOwner))
+        callStack.addInstruction(CompoundInstruction(element.result))
+    }
+}
+
+private fun unfoldThrow(expression: IrThrow, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(expression))
+    callStack.addInstruction(CompoundInstruction(expression.value))
+}
+
+private fun unfoldStringConcatenation(expression: IrStringConcatenation, environment: IrInterpreterEnvironment) {
+    val callStack = environment.callStack
+    callStack.newSubFrame(expression, listOf())
+    callStack.addInstruction(SimpleInstruction(expression))
+
+    // this callback is used to check the need for an explicit toString call
+    val explicitToStringCheck = fun() {
+        when (val state = callStack.peekState()) {
+            is Common -> {
+                callStack.popState()
+                // TODO this check can be dropped after serialization introduction
+                // for now declarations in unsigned class don't have bodies and must be treated separately
+                if (state.irClass.defaultType.isUnsigned()) {
+                    val result = when (val value = (state.fields.single().state as Primitive<*>).value) {
+                        is Byte -> value.toUByte().toString()
+                        is Short -> value.toUShort().toString()
+                        is Int -> value.toUInt().toString()
+                        else -> (value as Number).toLong().toULong().toString()
+                    }
+                    return callStack.pushState(result.toState(environment.irBuiltIns.stringType))
+                }
+                val toStringFun = state.getToStringFunction()
+                val receiver = toStringFun.dispatchReceiverParameter!!
+                val toStringCall = IrCallImpl.fromSymbolOwner(0, 0, environment.irBuiltIns.stringType, toStringFun.symbol)
+                toStringCall.dispatchReceiver = IrConstImpl.constNull(0, 0, receiver.type) // just stub receiver
+
+                callStack.newSubFrame(toStringCall, listOf(SimpleInstruction(toStringCall)))
+                callStack.pushState(state)
+            }
+        }
+    }
+    expression.arguments.reversed().forEach {
+        callStack.addInstruction(CustomInstruction(explicitToStringCheck))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+}
+
+private fun unfoldComposite(element: IrComposite, callStack: CallStack) {
+    when (element.origin) {
+        IrStatementOrigin.DESTRUCTURING_DECLARATION -> element.statements.reversed()
+            .forEach { callStack.addInstruction(CompoundInstruction(it)) }
+        null -> element.statements.reversed()
+            .forEach { callStack.addInstruction(CompoundInstruction(it)) } // is null for body of do while loop
+        else -> TODO("${element.origin} not implemented")
+    }
+}
+
+private fun unfoldFunctionReference(reference: IrFunctionReference, callStack: CallStack) {
+    val function = reference.symbol.owner
+    callStack.newSubFrame(reference, listOf())
+    callStack.addInstruction(SimpleInstruction(reference))
+
+    reference.extensionReceiver?.let {
+        callStack.addInstruction(SimpleInstruction(function.extensionReceiverParameter!!))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+    reference.dispatchReceiver?.let {
+        callStack.addInstruction(SimpleInstruction(function.dispatchReceiverParameter!!))
+        callStack.addInstruction(CompoundInstruction(it))
+    }
+}
+
+private fun unfoldPropertyReference(propertyReference: IrPropertyReference, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(propertyReference))
+    callStack.addInstruction(CompoundInstruction(propertyReference.dispatchReceiver))
+}
+
+private fun unfoldClassReference(classReference: IrClassReference, callStack: CallStack) {
+    callStack.addInstruction(SimpleInstruction(classReference))
+}
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.ir.interpreter
+
+import org.jetbrains.kotlin.ir.declarations.IrClass
+import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.interpreter.stack.CallStack
+import org.jetbrains.kotlin.ir.interpreter.state.Complex
+import org.jetbrains.kotlin.ir.symbols.IrSymbol
+import org.jetbrains.kotlin.ir.util.isSubclassOf
+
+internal class IrInterpreterEnvironment(val irBuiltIns: IrBuiltIns, val callStack: CallStack) {
+    val irExceptions = mutableListOf<IrClass>()
+    var mapOfEnums = mutableMapOf<IrSymbol, Complex>()
+    var mapOfObjects = mutableMapOf<IrSymbol, Complex>()
+
+    private constructor(environment: IrInterpreterEnvironment) : this(environment.irBuiltIns, CallStack()) {
+        irExceptions.addAll(environment.irExceptions)
+        mapOfEnums = environment.mapOfEnums
+        mapOfObjects = environment.mapOfObjects
+    }
+
+    constructor(irModule: IrModuleFragment) : this(irModule.irBuiltins, CallStack()) {
+        irExceptions.addAll(
+            irModule.files
+                .flatMap { it.declarations }
+                .filterIsInstance<IrClass>()
+                .filter { it.isSubclassOf(irBuiltIns.throwableClass.owner) }
+        )
+    }
+
+    fun copyWithNewCallStack(): IrInterpreterEnvironment {
+        return IrInterpreterEnvironment(this)
+    }
+
+    companion object {
+        const val MAX_STACK = 10_000
+        const val MAX_COMMANDS = 1_000_000
+    }
+}
@@ -1,89 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.ir.interpreter
-
-import org.jetbrains.kotlin.ir.interpreter.stack.Stack
-import org.jetbrains.kotlin.ir.interpreter.state.Primitive
-import org.jetbrains.kotlin.ir.interpreter.state.isSubtypeOf
-import org.jetbrains.kotlin.ir.IrElement
-import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
-import org.jetbrains.kotlin.ir.expressions.*
-import org.jetbrains.kotlin.ir.interpreter.exceptions.throwAsUserException
-import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
-import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.types.classifierOrFail
-import org.jetbrains.kotlin.ir.types.classifierOrNull
-import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
-import org.jetbrains.kotlin.ir.util.render
-
-enum class ReturnLabel {
-    REGULAR, RETURN, BREAK_LOOP, BREAK_WHEN, CONTINUE, EXCEPTION
-}
-
-open class ExecutionResult(val returnLabel: ReturnLabel, private val owner: IrElement? = null) {
-    fun getNextLabel(irElement: IrElement, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        return when (returnLabel) {
-            ReturnLabel.RETURN -> when (irElement) {
-                is IrCall, is IrReturnableBlock, is IrSimpleFunction -> if (owner == irElement) Next else this
-                else -> this
-            }
-            ReturnLabel.BREAK_WHEN -> when (irElement) {
-                is IrWhen -> Next
-                else -> this
-            }
-            ReturnLabel.BREAK_LOOP -> when (irElement) {
-                is IrWhileLoop, is IrDoWhileLoop -> if (owner == irElement) Next else this
-                else -> this
-            }
-            ReturnLabel.CONTINUE -> when (irElement) {
-                is IrWhileLoop -> if (owner == irElement) irElement.interpret() else this
-                is IrDoWhileLoop -> {
-                    if (owner != irElement) return this
-                    error("Continue must be handled inside DoWhile interpreter function")
-                }
-                else -> this
-            }
-            ReturnLabel.EXCEPTION -> Exception
-            ReturnLabel.REGULAR -> Next
-        }
-    }
-
-    fun addOwnerInfo(owner: IrElement): ExecutionResult {
-        return ExecutionResult(returnLabel, owner)
-    }
-}
-
-inline fun ExecutionResult.check(
-    vararg toCheckLabel: ReturnLabel = arrayOf(ReturnLabel.REGULAR), returnBlock: (ExecutionResult) -> Unit
-): ExecutionResult {
-    if (this.returnLabel !in toCheckLabel) returnBlock(this)
-    return this
-}
-
-/**
- * This method is analog of `checkcast` jvm bytecode operation. Throw exception whenever actual type is not a subtype of expected.
- */
-internal fun ExecutionResult.implicitCastIfNeeded(expectedType: IrType, actualType: IrType, stack: Stack): ExecutionResult {
-    if (actualType.classifierOrNull !is IrTypeParameterSymbol) return this
-
-    if (expectedType.classifierOrFail is IrTypeParameterSymbol) return this
-
-    val actualState = stack.peekReturnValue()
-    if (actualState is Primitive<*> && actualState.value == null) return this // this is handled as NullPointerException
-
-    if (!actualState.isSubtypeOf(expectedType)) {
-        val convertibleClassName = stack.popReturnValue().irClass.fqNameWhenAvailable
-        ClassCastException("$convertibleClassName cannot be cast to ${expectedType.render()}").throwAsUserException()
-    }
-    return this
-}
-
-object Next : ExecutionResult(ReturnLabel.REGULAR)
-object Return : ExecutionResult(ReturnLabel.RETURN)
-object BreakLoop : ExecutionResult(ReturnLabel.BREAK_LOOP)
-object BreakWhen : ExecutionResult(ReturnLabel.BREAK_WHEN)
-object Continue : ExecutionResult(ReturnLabel.CONTINUE)
-object Exception : ExecutionResult(ReturnLabel.EXCEPTION)
@@ -13,12 +13,13 @@ import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrErrorExpressionImpl
 import org.jetbrains.kotlin.ir.interpreter.builtins.evaluateIntrinsicAnnotation
-import org.jetbrains.kotlin.ir.interpreter.exceptions.throwAsUserException
 import org.jetbrains.kotlin.ir.interpreter.stack.Variable
 import org.jetbrains.kotlin.ir.interpreter.state.*
 import org.jetbrains.kotlin.ir.interpreter.proxy.Proxy
 import org.jetbrains.kotlin.ir.interpreter.proxy.wrap
+import org.jetbrains.kotlin.ir.interpreter.state.reflection.KTypeState
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.types.impl.buildSimpleType
@@ -28,7 +29,6 @@ import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.util.capitalizeDecapitalize.capitalizeAsciiOnly
-import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 import java.lang.invoke.MethodType
 import kotlin.math.min

@@ -53,6 +53,9 @@ internal fun State.toIrExpression(expression: IrExpression): IrExpression {
                type.isPrimitiveType() || type.isString() -> this.value.toIrConst(type, start, end)
                else -> expression // TODO support for arrays
            }
+        is ExceptionState -> {
+            IrErrorExpressionImpl(expression.startOffset, expression.endOffset, expression.type, "\n" + this.getFullDescription())
+        }
        is Complex -> {
            val stateType = this.irClass.defaultType
            when {
@@ -234,17 +237,51 @@ fun IrClass.internalName(): String {
    return internalName.toString()
 }

-inline fun withExceptionHandler(block: () -> Any?): Any? {
+internal inline fun withExceptionHandler(environment: IrInterpreterEnvironment, block: () -> Unit) {
    try {
-        return block()
+        block()
+        // check if during proxy interpretation was an exception
+        val possibleException = environment.callStack.peekState() as? ExceptionState
+        if (possibleException != null) environment.callStack.dropFramesUntilTryCatch()
    } catch (e: Throwable) {
-        e.throwAsUserException()
+        e.handleUserException(environment)
    }
 }

-internal fun IrFunction.getArgsForMethodInvocation(interpreter: IrInterpreter, methodType: MethodType, args: List<Variable>): List<Any?> {
+internal fun Throwable.handleUserException(environment: IrInterpreterEnvironment) {
+    val exceptionName = this::class.java.simpleName
+    val irExceptionClass = environment.irExceptions.firstOrNull { it.name.asString() == exceptionName }
+        ?: environment.irBuiltIns.throwableClass.owner
+    environment.callStack.pushState(ExceptionState(this, irExceptionClass, environment.callStack.getStackTrace()))
+    environment.callStack.dropFramesUntilTryCatch()
+}
+
+/**
+ * This method is analog of `checkcast` jvm bytecode operation. Throw exception whenever actual type is not a subtype of expected.
+ */
+internal fun IrFunction?.checkCast(environment: IrInterpreterEnvironment): Boolean {
+    this ?: return true
+    val actualType = this.returnType
+    if (actualType.classifierOrNull !is IrTypeParameterSymbol) return true
+
+    // TODO expectedType can be missing for functions called as proxy
+    val expectedType = (environment.callStack.getVariable(this.symbol).state as? KTypeState)?.irType ?: return true
+    if (expectedType.classifierOrFail is IrTypeParameterSymbol) return true
+
+    val actualState = environment.callStack.peekState() ?: return true
+    if (actualState is Primitive<*> && actualState.value == null) return true // this is handled in checkNullability
+
+    if (!actualState.isSubtypeOf(expectedType)) {
+        val convertibleClassName = environment.callStack.popState().irClass.fqNameWhenAvailable
+        ClassCastException("$convertibleClassName cannot be cast to ${expectedType.render()}").handleUserException(environment)
+        return false
+    }
+    return true
+}
+
+internal fun IrFunction.getArgsForMethodInvocation(interpreter: IrInterpreter, methodType: MethodType, args: List<State>): List<Any?> {
    val argsValues = args
-        .mapIndexed { index, variable -> variable.state.wrap(interpreter, methodType.parameterType(index)) }
+        .mapIndexed { index, state -> state.wrap(interpreter, methodType.parameterType(index)) }
        .toMutableList()

    // TODO if vararg isn't last parameter
@@ -1,19 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.ir.interpreter.exceptions
-
-/**
- * This class used to wrap 2 types of exceptions:
- * 1. exceptions from JVM such as: ArithmeticException, StackOverflowError and others
- * 2. exceptions defined by user
- */
-class UserException(val exception: Throwable) : InterpreterException() {
-    override fun fillInStackTrace(): Throwable = this
-}
-
-fun Throwable.throwAsUserException(): Nothing {
-    throw UserException(this)
-}
@@ -5,25 +5,24 @@

 package org.jetbrains.kotlin.ir.interpreter.intrinsics

-import org.jetbrains.kotlin.ir.interpreter.ExecutionResult
-import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterMethodNotFoundError
-import org.jetbrains.kotlin.ir.interpreter.stack.Stack
-import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.interpreter.Instruction
+import org.jetbrains.kotlin.ir.interpreter.IrInterpreterEnvironment
+import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterMethodNotFoundError

-internal class IntrinsicEvaluator {
-    fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
+internal object IntrinsicEvaluator {
+    fun unwindInstructions(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
        return when {
-            EmptyArray.equalTo(irFunction) -> EmptyArray.evaluate(irFunction, stack, interpret)
-            ArrayOf.equalTo(irFunction) -> ArrayOf.evaluate(irFunction, stack, interpret)
-            ArrayOfNulls.equalTo(irFunction) -> ArrayOfNulls.evaluate(irFunction, stack, interpret)
-            EnumValues.equalTo(irFunction) -> EnumValues.evaluate(irFunction, stack, interpret)
-            EnumValueOf.equalTo(irFunction) -> EnumValueOf.evaluate(irFunction, stack, interpret)
-            EnumHashCode.equalTo(irFunction) -> EnumHashCode.evaluate(irFunction, stack, interpret)
-            JsPrimitives.equalTo(irFunction) -> JsPrimitives.evaluate(irFunction, stack, interpret)
-            ArrayConstructor.equalTo(irFunction) -> ArrayConstructor.evaluate(irFunction, stack, interpret)
-            SourceLocation.equalTo(irFunction) -> SourceLocation.evaluate(irFunction, stack, interpret)
-            AssertIntrinsic.equalTo(irFunction) -> AssertIntrinsic.evaluate(irFunction, stack, interpret)
+            EmptyArray.equalTo(irFunction) -> EmptyArray.unwind(irFunction, environment)
+            ArrayOf.equalTo(irFunction) -> ArrayOf.unwind(irFunction, environment)
+            ArrayOfNulls.equalTo(irFunction) -> ArrayOfNulls.unwind(irFunction, environment)
+            EnumValues.equalTo(irFunction) -> EnumValues.unwind(irFunction, environment)
+            EnumValueOf.equalTo(irFunction) -> EnumValueOf.unwind(irFunction, environment)
+            EnumHashCode.equalTo(irFunction) -> EnumHashCode.unwind(irFunction, environment)
+            JsPrimitives.equalTo(irFunction) -> JsPrimitives.unwind(irFunction, environment)
+            ArrayConstructor.equalTo(irFunction) -> ArrayConstructor.unwind(irFunction, environment)
+            SourceLocation.equalTo(irFunction) -> SourceLocation.unwind(irFunction, environment)
+            AssertIntrinsic.equalTo(irFunction) -> AssertIntrinsic.unwind(irFunction, environment)
            else -> throw InterpreterMethodNotFoundError("Method ${irFunction.name} hasn't implemented")
        }
    }
@@ -5,15 +5,14 @@

 package org.jetbrains.kotlin.ir.interpreter.intrinsics

-import org.jetbrains.kotlin.ir.interpreter.*
-import org.jetbrains.kotlin.ir.interpreter.stack.Stack
-import org.jetbrains.kotlin.ir.interpreter.stack.Variable
-import org.jetbrains.kotlin.ir.interpreter.state.*
-import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrEnumEntry
 import org.jetbrains.kotlin.ir.declarations.IrFunction
-import org.jetbrains.kotlin.ir.interpreter.exceptions.throwAsUserException
+import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
+import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
+import org.jetbrains.kotlin.ir.interpreter.*
+import org.jetbrains.kotlin.ir.interpreter.state.*
 import org.jetbrains.kotlin.ir.interpreter.state.reflection.KFunctionState
 import org.jetbrains.kotlin.ir.interpreter.state.reflection.KTypeState
 import org.jetbrains.kotlin.ir.types.IrSimpleType
@@ -22,12 +21,20 @@ import org.jetbrains.kotlin.ir.types.impl.buildSimpleType
 import org.jetbrains.kotlin.ir.types.impl.makeTypeProjection
 import org.jetbrains.kotlin.ir.types.isArray
 import org.jetbrains.kotlin.ir.types.isCharArray
-import org.jetbrains.kotlin.ir.util.*
+import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
 import org.jetbrains.kotlin.types.Variance

 internal sealed class IntrinsicBase {
    abstract fun equalTo(irFunction: IrFunction): Boolean
-    abstract fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult
+    abstract fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment)
+    abstract fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction>
+
+    fun customEvaluateInstruction(irFunction: IrFunction, environment: IrInterpreterEnvironment): CustomInstruction {
+        return CustomInstruction {
+            evaluate(irFunction, environment)
+            environment.callStack.dropFrameAndCopyResult()
+        }
+    }
 }

 internal object EmptyArray : IntrinsicBase() {
@@ -36,13 +43,13 @@ internal object EmptyArray : IntrinsicBase() {
        return fqName in setOf("kotlin.emptyArray", "kotlin.ArrayIntrinsicsKt.emptyArray")
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val typeArgument = irFunction.typeParameters.map { stack.getVariable(it.symbol) }.single().state as KTypeState
-        val returnType = (irFunction.returnType as IrSimpleType).buildSimpleType {
-            arguments = listOf(makeTypeProjection(typeArgument.irType, Variance.INVARIANT))
-        }
-        stack.pushReturnValue(emptyArray<Any?>().toState(returnType))
-        return Next
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        return listOf(customEvaluateInstruction(irFunction, environment))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val returnType = environment.callStack.getVariable(irFunction.symbol).state as KTypeState
+        environment.callStack.pushState(emptyArray<Any?>().toState(returnType.irType))
    }
 }

@@ -52,10 +59,14 @@ internal object ArrayOf : IntrinsicBase() {
        return fqName == "kotlin.arrayOf"
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val elementsVariable = irFunction.valueParameters.single().symbol
-        stack.pushReturnValue(stack.getVariable(elementsVariable).state)
-        return Next
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        return listOf(customEvaluateInstruction(irFunction, environment))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val elementsSymbol = irFunction.valueParameters.single().symbol
+        val varargVariable = environment.callStack.getVariable(elementsSymbol).state
+        environment.callStack.pushState(varargVariable)
    }
 }

@@ -65,15 +76,19 @@ internal object ArrayOfNulls : IntrinsicBase() {
        return fqName == "kotlin.arrayOfNulls"
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val size = stack.getVariable(irFunction.valueParameters.first().symbol).state.asInt()
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        return listOf(customEvaluateInstruction(irFunction, environment))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val size = environment.callStack.getVariable(irFunction.valueParameters.first().symbol).state.asInt()
        val array = arrayOfNulls<Any?>(size)
-        val typeArgument = irFunction.typeParameters.map { stack.getVariable(it.symbol) }.single().state as KTypeState
+        val typeArgument = irFunction.typeParameters.map { environment.callStack.getVariable(it.symbol) }.single().state as KTypeState
        val returnType = (irFunction.returnType as IrSimpleType).buildSimpleType {
            arguments = listOf(makeTypeProjection(typeArgument.irType, Variance.INVARIANT))
        }
-        stack.pushReturnValue(array.toState(returnType))
-        return Next
+
+        environment.callStack.pushState(array.toState(returnType))
    }
 }

@@ -83,19 +98,28 @@ internal object EnumValues : IntrinsicBase() {
        return (fqName == "kotlin.enumValues" || fqName.endsWith(".values")) && irFunction.valueParameters.isEmpty()
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val enumClass = when (irFunction.fqNameWhenAvailable.toString()) {
+    private fun getEnumClass(irFunction: IrFunction, environment: IrInterpreterEnvironment): IrClass {
+        return when (irFunction.fqNameWhenAvailable.toString()) {
            "kotlin.enumValues" -> {
-                val kType = stack.getVariable(irFunction.typeParameters.first().symbol).state as KTypeState
+                val kType = environment.callStack.getVariable(irFunction.typeParameters.first().symbol).state as KTypeState
                kType.irType.classOrNull!!.owner
            }
            else -> irFunction.parent as IrClass
        }
+    }

+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        val enumClass = getEnumClass(irFunction, environment)
        val enumEntries = enumClass.declarations.filterIsInstance<IrEnumEntry>()
-            .map { entry -> entry.interpret().check { return it }.let { stack.popReturnValue() as Common } }
-        stack.pushReturnValue(enumEntries.toTypedArray().toState(irFunction.returnType))
-        return Next
+
+        return listOf(customEvaluateInstruction(irFunction, environment)) + enumEntries.reversed().map { CompoundInstruction(it) }
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val enumClass = getEnumClass(irFunction, environment)
+
+        val enumEntries = enumClass.declarations.filterIsInstance<IrEnumEntry>().map { environment.mapOfEnums[it.symbol] }
+        environment.callStack.pushState(enumEntries.toTypedArray().toState(irFunction.returnType))
    }
 }

@@ -105,20 +129,34 @@ internal object EnumValueOf : IntrinsicBase() {
        return (fqName == "kotlin.enumValueOf" || fqName.endsWith(".valueOf")) && irFunction.valueParameters.size == 1
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val enumClass = when (irFunction.fqNameWhenAvailable.toString()) {
+    private fun getEnumClass(irFunction: IrFunction, environment: IrInterpreterEnvironment): IrClass {
+        return when (irFunction.fqNameWhenAvailable.toString()) {
            "kotlin.enumValueOf" -> {
-                val kType = stack.getVariable(irFunction.typeParameters.first().symbol).state as KTypeState
+                val kType = environment.callStack.getVariable(irFunction.typeParameters.first().symbol).state as KTypeState
                kType.irType.classOrNull!!.owner
            }
            else -> irFunction.parent as IrClass
        }
-        val enumEntryName = stack.getVariable(irFunction.valueParameters.first().symbol).state.asString()
-        val enumEntry = enumClass.declarations.filterIsInstance<IrEnumEntry>().singleOrNull { it.name.asString() == enumEntryName }
-        enumEntry?.interpret()?.check { return it }
-            ?: IllegalArgumentException("No enum constant ${enumClass.fqNameWhenAvailable}.$enumEntryName").throwAsUserException()
+    }

-        return Next
+    private fun getEnumEntryByName(irFunction: IrFunction, environment: IrInterpreterEnvironment): IrEnumEntry? {
+        val enumClass = getEnumClass(irFunction, environment)
+        val enumEntryName = environment.callStack.getVariable(irFunction.valueParameters.first().symbol).state.asString()
+        val enumEntry = enumClass.declarations.filterIsInstance<IrEnumEntry>().singleOrNull { it.name.asString() == enumEntryName }
+        if (enumEntry == null) {
+            IllegalArgumentException("No enum constant ${enumClass.fqNameWhenAvailable}.$enumEntryName").handleUserException(environment)
+        }
+        return enumEntry
+    }
+
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        val enumEntry = getEnumEntryByName(irFunction, environment) ?: return emptyList()
+        return listOf(customEvaluateInstruction(irFunction, environment), CompoundInstruction(enumEntry))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val enumEntry = getEnumEntryByName(irFunction, environment)!!
+        environment.callStack.pushState(environment.mapOfEnums[enumEntry.symbol]!!)
    }
 }

@@ -128,10 +166,13 @@ internal object EnumHashCode : IntrinsicBase() {
        return fqName == "kotlin.Enum.hashCode"
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val hashCode = stack.getAll().single().state.hashCode()
-        stack.pushReturnValue(hashCode.toState(irFunction.returnType))
-        return Next
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        return listOf(customEvaluateInstruction(irFunction, environment))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val hashCode = environment.callStack.getVariable(irFunction.dispatchReceiverParameter!!.symbol).state.hashCode()
+        environment.callStack.pushState(hashCode.toState(irFunction.returnType))
    }
 }

@@ -141,19 +182,22 @@ internal object JsPrimitives : IntrinsicBase() {
        return fqName == "kotlin.Long.<init>" || fqName == "kotlin.Char.<init>"
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        return listOf(customEvaluateInstruction(irFunction, environment))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
        when (irFunction.fqNameWhenAvailable.toString()) {
            "kotlin.Long.<init>" -> {
-                val low = stack.getVariable(irFunction.valueParameters[0].symbol).state.asInt()
-                val high = stack.getVariable(irFunction.valueParameters[1].symbol).state.asInt()
-                stack.pushReturnValue((high.toLong().shl(32) + low).toState(irFunction.returnType))
+                val low = environment.callStack.getVariable(irFunction.valueParameters[0].symbol).state.asInt()
+                val high = environment.callStack.getVariable(irFunction.valueParameters[1].symbol).state.asInt()
+                environment.callStack.pushState((high.toLong().shl(32) + low).toState(irFunction.returnType))
            }
            "kotlin.Char.<init>" -> {
-                val value = stack.getVariable(irFunction.valueParameters[0].symbol).state.asInt()
-                stack.pushReturnValue(value.toChar().toState(irFunction.returnType))
+                val value = environment.callStack.getVariable(irFunction.valueParameters[0].symbol).state.asInt()
+                environment.callStack.pushState(value.toChar().toState(irFunction.returnType))
            }
        }
-        return Next
    }
 }

@@ -163,24 +207,36 @@ internal object ArrayConstructor : IntrinsicBase() {
        return fqName.matches("kotlin\\.(Byte|Char|Short|Int|Long|Float|Double|Boolean|)Array\\.<init>".toRegex())
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        if (irFunction.valueParameters.size == 1) return listOf(customEvaluateInstruction(irFunction, environment))
+        val instructions = mutableListOf<Instruction>(customEvaluateInstruction(irFunction, environment))
+
        val sizeDescriptor = irFunction.valueParameters[0].symbol
-        val size = stack.getVariable(sizeDescriptor).state.asInt()
+        val size = environment.callStack.getVariable(sizeDescriptor).state.asInt()
+
+        val initDescriptor = irFunction.valueParameters[1].symbol
+        val initLambda = environment.callStack.getVariable(initDescriptor).state as KFunctionState
+        environment.callStack.loadUpValues(initLambda)
+        val function = initLambda.irFunction as IrSimpleFunction
+        val index = initLambda.irFunction.valueParameters.single()
+        for (i in 0 until size) {
+            val call = IrCallImpl.fromSymbolOwner(0, 0, function.returnType, function.symbol)
+            call.putValueArgument(0, IrConstImpl.int(0, 0, index.type, i))
+            instructions += CompoundInstruction(call)
+        }
+
+        return instructions
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val sizeDescriptor = irFunction.valueParameters[0].symbol
+        val size = environment.callStack.getVariable(sizeDescriptor).state.asInt()
        val arrayValue = MutableList<Any?>(size) { if (irFunction.returnType.isCharArray()) 0.toChar() else 0 }

        if (irFunction.valueParameters.size == 2) {
-            val initDescriptor = irFunction.valueParameters[1].symbol
-            val initLambda = stack.getVariable(initDescriptor).state as KFunctionState
-            val index = initLambda.irFunction.valueParameters.single()
-            val nonLocalDeclarations = initLambda.extractNonLocalDeclarations()
            for (i in 0 until size) {
-                val indexVar = listOf(Variable(index.symbol, i.toState(index.type)))
-                // TODO throw exception if label != RETURN
-                stack.newFrame(
-                    asSubFrame = initLambda.irFunction.isLocal || initLambda.irFunction.isInline,
-                    initPool = nonLocalDeclarations + indexVar
-                ) { initLambda.irFunction.body!!.interpret() }.check(ReturnLabel.RETURN) { return it }
-                arrayValue[i] = stack.popReturnValue().let {
+                arrayValue[i] = environment.callStack.popState().let {
+                    // TODO wrap
                    when (it) {
                        is Wrapper -> it.value
                        is Primitive<*> -> if (it.type.isArray() || it.type.isPrimitiveArray()) it else it.value
@@ -190,8 +246,8 @@ internal object ArrayConstructor : IntrinsicBase() {
            }
        }

-        stack.pushReturnValue(arrayValue.toPrimitiveStateArray(irFunction.parentAsClass.defaultType))
-        return Next
+        val type = environment.callStack.getVariable(irFunction.symbol).state as KTypeState
+        environment.callStack.pushState(arrayValue.toPrimitiveStateArray(type.irType))
    }
 }

@@ -201,9 +257,12 @@ internal object SourceLocation : IntrinsicBase() {
        return fqName == "kotlin.experimental.sourceLocation" || fqName == "kotlin.experimental.SourceLocationKt.sourceLocation"
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        stack.pushReturnValue(stack.getCurrentStackInfo().toState(irFunction.returnType))
-        return Next
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        return listOf(customEvaluateInstruction(irFunction, environment))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        environment.callStack.pushState(environment.callStack.getFileAndPositionInfo().toState(irFunction.returnType))
    }
 }

@@ -213,17 +272,22 @@ internal object AssertIntrinsic : IntrinsicBase() {
        return fqName == "kotlin.PreconditionsKt.assert"
    }

-    override fun evaluate(irFunction: IrFunction, stack: Stack, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
-        val value = stack.getVariable(irFunction.valueParameters.first().symbol).state.asBoolean()
+    override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
+        if (irFunction.valueParameters.size == 1) return listOf(customEvaluateInstruction(irFunction, environment))
+
+        val messageLambda = environment.callStack.getVariable(irFunction.valueParameters.last().symbol).state as KFunctionState
+        val function = messageLambda.irFunction as IrSimpleFunction
+        val call = IrCallImpl.fromSymbolOwner(0, 0, function.returnType, function.symbol)
+
+        return listOf(customEvaluateInstruction(irFunction, environment), CompoundInstruction(call))
+    }
+
+    override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
+        val value = environment.callStack.getVariable(irFunction.valueParameters.first().symbol).state.asBoolean()
+        if (value) return
        when (irFunction.valueParameters.size) {
-            1 -> if (!value) AssertionError("Assertion failed").throwAsUserException()
-            2 -> if (!value) {
-                val messageLambda = stack.getVariable(irFunction.valueParameters.last().symbol).state as KFunctionState
-                stack.newFrame(asSubFrame = true) { messageLambda.irFunction.body!!.interpret() }
-                    .check(ReturnLabel.RETURN) { return it }
-                AssertionError(stack.popReturnValue().asString()).throwAsUserException()
-            }
+            1 -> AssertionError("Assertion failed").handleUserException(environment)
+            2 -> AssertionError(environment.callStack.popState().asString()).handleUserException(environment)
        }
-        return Next
    }
 }
@@ -33,7 +33,7 @@ internal class CommonProxy private constructor(
        equalsFun.getDispatchReceiver()!!.let { valueArguments.add(Variable(it, state)) }
        valueArguments.add(Variable(equalsFun.valueParameters.single().symbol, other.state))

-        return with(interpreter) { equalsFun.interpret(valueArguments) } as Boolean
+        return with(interpreter) { equalsFun.proxyInterpret(valueArguments) } as Boolean
    }

    override fun hashCode(): Int {
@@ -42,7 +42,7 @@ internal class CommonProxy private constructor(
        if (hashCodeFun.isFakeOverriddenFromAny() || calledFromBuiltIns) return System.identityHashCode(state)

        hashCodeFun.getDispatchReceiver()!!.let { valueArguments.add(Variable(it, state)) }
-        return with(interpreter) { hashCodeFun.interpret(valueArguments) } as Int
+        return with(interpreter) { hashCodeFun.proxyInterpret(valueArguments) } as Int
    }

    override fun toString(): String {
@@ -53,7 +53,7 @@ internal class CommonProxy private constructor(
        }

        toStringFun.getDispatchReceiver()!!.let { valueArguments.add(Variable(it, state)) }
-        return with(interpreter) { toStringFun.interpret(valueArguments) } as String
+        return with(interpreter) { toStringFun.proxyInterpret(valueArguments) } as String
    }

    companion object {
@@ -79,7 +79,7 @@ internal class CommonProxy private constructor(
                        valueArguments += Variable(irFunction.getDispatchReceiver()!!, commonProxy.state)
                        valueArguments += irFunction.valueParameters
                            .mapIndexed { index, parameter -> Variable(parameter.symbol, args[index].toState(parameter.type)) }
-                        with(interpreter) { irFunction.interpret(valueArguments, method.returnType) }
+                        with(interpreter) { irFunction.proxyInterpret(valueArguments, method.returnType) }
                    }
                }
            }
@@ -48,7 +48,7 @@ internal class KFunctionProxy(
        val extensionReceiver = state.irFunction.extensionReceiverParameter?.let { Variable(it.symbol, args[index++].toState(it.type)) }
        val valueArguments = listOfNotNull(dispatchReceiver, extensionReceiver) +
                state.irFunction.valueParameters.map { parameter -> Variable(parameter.symbol, args[index++].toState(parameter.type)) }
-        return with(interpreter) { state.irFunction.interpret(valueArguments) }
+        return with(interpreter) { state.irFunction.proxyInterpret(valueArguments) }
    }

    override fun callBy(args: Map<KParameter, Any?>): Any? {
@@ -6,8 +6,6 @@
 package org.jetbrains.kotlin.ir.interpreter.proxy.reflection

 import org.jetbrains.kotlin.ir.interpreter.IrInterpreter
-import org.jetbrains.kotlin.ir.interpreter.proxy.Proxy
-import org.jetbrains.kotlin.ir.interpreter.proxy.wrap
 import org.jetbrains.kotlin.ir.interpreter.stack.Variable
 import org.jetbrains.kotlin.ir.interpreter.state.reflection.KPropertyState
 import org.jetbrains.kotlin.ir.interpreter.toState
@@ -24,7 +22,7 @@ internal open class KProperty1Proxy(
                checkArguments(1, args.size)
                val receiverParameter = getter.dispatchReceiverParameter ?: getter.extensionReceiverParameter
                val receiver = Variable(receiverParameter!!.symbol, args[0].toState(receiverParameter.type))
-                return with(this@KProperty1Proxy.interpreter) { getter.interpret(listOf(receiver)) }
+                return with(this@KProperty1Proxy.interpreter) { getter.proxyInterpret(listOf(receiver)) }
            }

            override fun callBy(args: Map<KParameter, Any?>): Any? {
@@ -54,7 +52,7 @@ internal class KMutableProperty1Proxy(
                val receiver = Variable(receiverParameter!!.symbol, args[0].toState(receiverParameter.type))
                val valueParameter = setter.valueParameters.single()
                val value = Variable(valueParameter.symbol, args[1].toState(valueParameter.type))
-                with(this@KMutableProperty1Proxy.interpreter) { setter.interpret(listOf(receiver, value)) }
+                with(this@KMutableProperty1Proxy.interpreter) { setter.proxyInterpret(listOf(receiver, value)) }
            }

            override fun callBy(args: Map<KParameter, Any?>) {
@@ -14,15 +14,15 @@ import kotlin.reflect.*
 internal open class KProperty2Proxy(
    override val state: KPropertyState, override val interpreter: IrInterpreter
 ) : AbstractKPropertyProxy(state, interpreter), KProperty2<Any?, Any?, Any?> {
-    override val getter: KProperty2.Getter<Any?, Any?, Any?> =
-        object : Getter(state.property.getter!!), KProperty2.Getter<Any?, Any?, Any?> {
+    override val getter: KProperty2.Getter<Any?, Any?, Any?>
+        get() = object : Getter(state.property.getter!!), KProperty2.Getter<Any?, Any?, Any?> {
            override fun invoke(p1: Any?, p2: Any?): Any? = call(p1, p2)

            override fun call(vararg args: Any?): Any? {
                checkArguments(2, args.size)
                val dispatch = Variable(getter.dispatchReceiverParameter!!.symbol, args[0].toState(getter.dispatchReceiverParameter!!.type))
                val extension = Variable(getter.extensionReceiverParameter!!.symbol, args[1].toState(getter.extensionReceiverParameter!!.type))
-                return with(this@KProperty2Proxy.interpreter) { getter.interpret(listOf(dispatch, extension)) }
+                return with(this@KProperty2Proxy.interpreter) { getter.proxyInterpret(listOf(dispatch, extension)) }
            }

            override fun callBy(args: Map<KParameter, Any?>): Any? {
@@ -0,0 +1,201 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.ir.interpreter.stack
+
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.interpreter.CompoundInstruction
+import org.jetbrains.kotlin.ir.interpreter.Instruction
+import org.jetbrains.kotlin.ir.interpreter.SimpleInstruction
+import org.jetbrains.kotlin.ir.interpreter.state.State
+import org.jetbrains.kotlin.ir.interpreter.state.StateWithClosure
+import org.jetbrains.kotlin.ir.symbols.IrSymbol
+import org.jetbrains.kotlin.ir.util.fileOrNull
+
+internal class CallStack {
+    private val frames = mutableListOf<Frame>()
+    private fun getCurrentFrame() = frames.last()
+    internal fun getCurrentFrameOwner() = frames.last().currentSubFrameOwner
+
+    fun newFrame(frameOwner: IrElement, instructions: List<Instruction>, irFile: IrFile? = null) {
+        val newFrame = SubFrame(instructions.toMutableList(), frameOwner)
+        frames.add(Frame(newFrame, irFile))
+    }
+
+    fun newFrame(frameOwner: IrFunction, instructions: List<Instruction>) {
+        val newFrame = SubFrame(instructions.toMutableList(), frameOwner)
+        frames.add(Frame(newFrame, frameOwner.fileOrNull))
+    }
+
+    fun newSubFrame(frameOwner: IrElement, instructions: List<Instruction>) {
+        val newFrame = SubFrame(instructions.toMutableList(), frameOwner)
+        getCurrentFrame().addSubFrame(newFrame)
+    }
+
+    fun dropFrame() {
+        frames.removeLast()
+    }
+
+    fun dropFrameAndCopyResult() {
+        val result = peekState() ?: return dropFrame()
+        popState()
+        dropFrame()
+        pushState(result)
+    }
+
+    fun dropSubFrame() {
+        getCurrentFrame().removeSubFrame()
+    }
+
+    fun returnFromFrameWithResult(irReturn: IrReturn) {
+        val result = popState()
+        var frameOwner = getCurrentFrameOwner()
+        while (frameOwner != irReturn.returnTargetSymbol.owner) {
+            when (frameOwner) {
+                is IrTry -> {
+                    dropSubFrame()
+                    pushState(result)
+                    addInstruction(SimpleInstruction(irReturn))
+                    addInstruction(CompoundInstruction(frameOwner.finallyExpression))
+                    return
+                }
+                is IrCatch -> {
+                    val tryBlock = getCurrentFrame().dropInstructions()!!.element as IrTry// last instruction in `catch` block is `try`
+                    dropSubFrame()
+                    pushState(result)
+                    addInstruction(SimpleInstruction(irReturn))
+                    addInstruction(CompoundInstruction(tryBlock.finallyExpression))
+                    return
+                }
+                else -> {
+                    dropSubFrame()
+                    if (getCurrentFrame().hasNoSubFrames() && frameOwner != irReturn.returnTargetSymbol.owner) dropFrame()
+                    frameOwner = getCurrentFrameOwner()
+                }
+            }
+        }
+
+        dropFrame()
+        // check that last frame is not a function itself; use case for proxyInterpret
+        if (frames.size == 0) newFrame(irReturn, emptyList()) // just stub frame
+        pushState(result)
+    }
+
+    fun unrollInstructionsForBreakContinue(breakOrContinue: IrBreakContinue) {
+        var frameOwner = getCurrentFrameOwner()
+        while (frameOwner != breakOrContinue.loop) {
+            when (frameOwner) {
+                is IrTry -> {
+                    getCurrentFrame().removeSubFrameWithoutDataPropagation()
+                    addInstruction(CompoundInstruction(breakOrContinue))
+                    newSubFrame(frameOwner, listOf(SimpleInstruction(frameOwner))) // will be deleted when interpret 'try'
+                    return
+                }
+                is IrCatch -> {
+                    val tryInstruction = getCurrentFrame().dropInstructions()!! // last instruction in `catch` block is `try`
+                    getCurrentFrame().removeSubFrameWithoutDataPropagation()
+                    addInstruction(CompoundInstruction(breakOrContinue))
+                    newSubFrame(tryInstruction.element!!, listOf(tryInstruction))  // will be deleted when interpret 'try'
+                    return
+                }
+                else -> {
+                    getCurrentFrame().removeSubFrameWithoutDataPropagation()
+                    frameOwner = getCurrentFrameOwner()
+                }
+            }
+        }
+
+        when (breakOrContinue) {
+            is IrBreak -> getCurrentFrame().removeSubFrameWithoutDataPropagation() // drop loop
+            else -> if (breakOrContinue.loop is IrDoWhileLoop) {
+                addInstruction(SimpleInstruction(breakOrContinue.loop))
+                addInstruction(CompoundInstruction(breakOrContinue.loop.condition))
+            } else {
+                addInstruction(CompoundInstruction(breakOrContinue.loop))
+            }
+        }
+    }
+
+    fun dropFramesUntilTryCatch() {
+        val exception = popState()
+        var frameOwner = getCurrentFrameOwner()
+        while (frames.isNotEmpty()) {
+            val frame = getCurrentFrame()
+            while (!frame.hasNoSubFrames()) {
+                frameOwner = frame.currentSubFrameOwner
+                when (frameOwner) {
+                    is IrTry -> {
+                        dropSubFrame()  // drop all instructions that left
+                        newSubFrame(frameOwner, listOf())
+                        addInstruction(SimpleInstruction(frameOwner)) // to evaluate finally at the end
+                        frameOwner.catches.reversed().forEach { addInstruction(CompoundInstruction(it)) }
+                        pushState(exception)
+                        return
+                    }
+                    is IrCatch -> {
+                        // in case of exception in catch, drop everything except of last `try` instruction
+                        addInstruction(frame.dropInstructions()!!)
+                        pushState(exception)
+                        return
+                    }
+                    else -> frame.removeSubFrameWithoutDataPropagation()
+                }
+            }
+            dropFrame()
+        }
+
+        if (frames.size == 0) newFrame(frameOwner, emptyList()) // just stub frame
+        pushState(exception)
+    }
+
+    fun hasNoInstructions() = frames.isEmpty() || (frames.size == 1 && frames.first().hasNoInstructions())
+
+    fun addInstruction(instruction: Instruction) {
+        getCurrentFrame().addInstruction(instruction)
+    }
+
+    fun popInstruction(): Instruction {
+        return getCurrentFrame().popInstruction()
+    }
+
+    fun pushState(state: State) {
+        getCurrentFrame().pushState(state)
+    }
+
+    fun popState(): State = getCurrentFrame().popState()
+    fun peekState(): State? = getCurrentFrame().peekState()
+
+    fun addVariable(variable: Variable) {
+        getCurrentFrame().addVariable(variable)
+    }
+
+    fun getVariable(symbol: IrSymbol): Variable = getCurrentFrame().getVariable(symbol)
+
+    fun storeUpValues(state: StateWithClosure) {
+        // TODO save only necessary declarations
+        state.upValues.addAll(getCurrentFrame().getAll().toMutableList())
+    }
+
+    fun loadUpValues(state: StateWithClosure) {
+        state.upValues.forEach { addVariable(it) }
+    }
+
+    fun copyUpValuesFromPreviousFrame() {
+        frames[frames.size - 2].getAll().forEach { addVariable(it) }
+    }
+
+    fun getStackTrace(): List<String> {
+        return frames.map { it.toString() }.filter { it != Frame.NOT_DEFINED }
+    }
+
+    fun getFileAndPositionInfo(): String {
+        return frames[frames.size - 2].getFileAndPositionInfo()
+    }
+
+    fun getStackCount(): Int = frames.size
+}
@@ -1,80 +1,143 @@
 /*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
 * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
 */

 package org.jetbrains.kotlin.ir.interpreter.stack

-import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterEmptyReturnStackError
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.interpreter.Instruction
+import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterError
 import org.jetbrains.kotlin.ir.interpreter.state.State
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
-import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
+import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
+import org.jetbrains.kotlin.util.capitalizeDecapitalize.capitalizeAsciiOnly
+import org.jetbrains.kotlin.utils.addToStdlib.firstNotNullResult

-internal interface Frame {
-    fun addVar(variable: Variable)
-    fun addAll(variables: List<Variable>)
-    fun getVariable(symbol: IrSymbol): Variable?
-    fun getAll(): List<Variable>
-    fun contains(symbol: IrSymbol): Boolean
-    fun pushReturnValue(state: State)
-    fun pushReturnValue(frame: Frame) // TODO rename to getReturnValueFrom
-    fun peekReturnValue(): State
-    fun popReturnValue(): State
-    fun hasReturnValue(): Boolean
+internal class Frame(subFrame: SubFrame, val irFile: IrFile? = null) {
+    private val innerStack = mutableListOf(subFrame)
+    private var currentInstruction: Instruction? = null
+    val currentSubFrameOwner: IrElement
+        get() = getCurrentFrame().owner
+
+    companion object {
+        const val NOT_DEFINED = "Not defined"
+    }
+
+    private fun getCurrentFrame() = innerStack.last()
+
+    fun addSubFrame(frame: SubFrame) {
+        innerStack.add(frame)
+    }
+
+    fun removeSubFrame() {
+        getCurrentFrame().peekState()?.let { if (innerStack.size > 1) innerStack[innerStack.size - 2].pushState(it) }
+        removeSubFrameWithoutDataPropagation()
+    }
+
+    fun removeSubFrameWithoutDataPropagation() {
+        innerStack.removeLast()
+    }
+
+    fun hasNoSubFrames() = innerStack.isEmpty()
+    fun hasNoInstructions() = hasNoSubFrames() || (innerStack.size == 1 && innerStack.first().isEmpty())
+
+    fun addInstruction(instruction: Instruction) {
+        getCurrentFrame().pushInstruction(instruction)
+    }
+
+    fun popInstruction(): Instruction {
+        return getCurrentFrame().popInstruction().apply { currentInstruction = this }
+    }
+
+    fun dropInstructions() = getCurrentFrame().dropInstructions()
+
+    fun pushState(state: State) {
+        getCurrentFrame().pushState(state)
+    }
+
+    fun popState(): State = getCurrentFrame().popState()
+    fun peekState(): State? = getCurrentFrame().peekState()
+
+    fun addVariable(variable: Variable) {
+        getCurrentFrame().addVariable(variable)
+    }
+
+    fun getVariable(symbol: IrSymbol): Variable {
+        return innerStack.firstNotNullResult { it.getVariable(symbol) }
+            ?: throw InterpreterError("$symbol not found") // TODO better message
+    }
+
+    fun getAll(): List<Variable> = innerStack.flatMap { it.getAll() }
+
+    private fun getLineNumberForCurrentInstruction(): String {
+        irFile ?: return ""
+        val frameOwner = currentInstruction?.element
+        return when {
+            frameOwner is IrExpression || (frameOwner is IrDeclaration && frameOwner.origin == IrDeclarationOrigin.DEFINED) ->
+                ":${irFile.fileEntry.getLineNumber(frameOwner.startOffset) + 1}"
+            else -> ""
+        }
+    }
+
+    fun getFileAndPositionInfo(): String {
+        irFile ?: return NOT_DEFINED
+        val lineNum = getLineNumberForCurrentInstruction()
+        return "${irFile.name}$lineNum"
+    }
+
+    override fun toString(): String {
+        irFile ?: return NOT_DEFINED
+        val fileNameCapitalized = irFile.name.replace(".kt", "Kt").capitalizeAsciiOnly()
+        val entryPoint = innerStack.firstOrNull { it.owner is IrFunction }?.owner as? IrFunction
+        val lineNum = getLineNumberForCurrentInstruction()
+
+        return "at $fileNameCapitalized.${entryPoint?.fqNameWhenAvailable ?: "<clinit>"}(${irFile.name}$lineNum)"
+    }
 }

-// TODO replace exceptions with InterpreterException
-internal class InterpreterFrame(
-    private val pool: MutableList<Variable> = mutableListOf(),
-    private val typeArguments: List<Variable> = listOf()
-) : Frame {
-    private val returnStack: MutableList<State> = mutableListOf()
+internal class SubFrame(private val instructions: MutableList<Instruction>, val owner: IrElement) {
+    private val memory = mutableListOf<Variable>()
+    private val dataStack = DataStack()

-    override fun addVar(variable: Variable) {
-        pool.add(variable)
+    fun isEmpty() = instructions.isEmpty()
+
+    fun pushInstruction(instruction: Instruction) {
+        instructions.add(0, instruction)
    }

-    override fun addAll(variables: List<Variable>) {
-        pool.addAll(variables)
+    fun popInstruction(): Instruction {
+        return instructions.removeFirst()
    }

-    override fun getVariable(symbol: IrSymbol): Variable? {
-        return (if (symbol is IrTypeParameterSymbol) typeArguments else pool).firstOrNull { it.symbol == symbol }
+    fun dropInstructions() = instructions.lastOrNull()?.apply { instructions.clear() }
+
+    fun pushState(state: State) {
+        dataStack.push(state)
    }

-    override fun getAll(): List<Variable> {
-        return pool
+    fun popState(): State = dataStack.pop()
+    fun peekState(): State? = if (!dataStack.isEmpty()) dataStack.peek() else null
+
+    fun addVariable(variable: Variable) {
+        memory += variable
    }

-    override fun contains(symbol: IrSymbol): Boolean {
-        return (typeArguments + pool).any { it.symbol == symbol }
-    }
-
-    override fun pushReturnValue(state: State) {
-        returnStack += state
-    }
-
-    override fun pushReturnValue(frame: Frame) {
-        if (frame.hasReturnValue()) this.pushReturnValue(frame.popReturnValue())
-    }
-
-    override fun hasReturnValue(): Boolean {
-        return returnStack.isNotEmpty()
-    }
-
-    override fun peekReturnValue(): State {
-        if (returnStack.isNotEmpty()) {
-            return returnStack.last()
-        }
-        throw InterpreterEmptyReturnStackError()
-    }
-
-    override fun popReturnValue(): State {
-        if (returnStack.isNotEmpty()) {
-            val item = returnStack.last()
-            returnStack.removeAt(returnStack.size - 1)
-            return item
-        }
-        throw InterpreterEmptyReturnStackError()
-    }
+    fun getVariable(symbol: IrSymbol): Variable? = memory.firstOrNull { it.symbol == symbol }
+    fun getAll(): List<Variable> = memory
 }
+
+private class DataStack {
+    private val stack = mutableListOf<State>()
+
+    fun isEmpty() = stack.isEmpty()
+
+    fun push(state: State) {
+        stack.add(state)
+    }
+
+    fun pop(): State = stack.removeLast()
+    fun peek(): State = stack.last()
+}
@@ -1,188 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.ir.interpreter.stack
-
-import org.jetbrains.kotlin.ir.declarations.IrFile
-import org.jetbrains.kotlin.ir.declarations.IrFunction
-import org.jetbrains.kotlin.ir.declarations.name
-import org.jetbrains.kotlin.ir.interpreter.ExecutionResult
-import org.jetbrains.kotlin.ir.interpreter.state.State
-import org.jetbrains.kotlin.ir.expressions.IrExpression
-import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterError
-import org.jetbrains.kotlin.ir.symbols.IrSymbol
-import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
-import org.jetbrains.kotlin.ir.util.fileOrNull
-import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
-import org.jetbrains.kotlin.ir.util.isLocal
-
-internal interface Stack {
-    fun newFrame(asSubFrame: Boolean = false, initPool: List<Variable> = listOf(), block: () -> ExecutionResult): ExecutionResult
-    fun newFrame(irFunction: IrFunction, initPool: List<Variable> = listOf(), block: () -> ExecutionResult): ExecutionResult
-    fun newFrame(irFile: IrFile?, initPool: List<Variable> = listOf(), block: () -> ExecutionResult): ExecutionResult
-
-    fun fixCallEntryPoint(irExpression: IrExpression)
-    fun getStackTrace(): List<String>
-    fun getCurrentStackInfo(): String
-    fun getStackCount(): Int
-
-    fun clean(rootFile: IrFile?)
-    fun addVar(variable: Variable)
-    fun addAll(variables: List<Variable>)
-    fun getVariable(symbol: IrSymbol): Variable
-    fun getAll(): List<Variable>
-
-    fun contains(symbol: IrSymbol): Boolean
-    fun hasReturnValue(): Boolean
-    fun pushReturnValue(state: State)
-    fun popReturnValue(): State
-    fun peekReturnValue(): State
-}
-
-internal class StackImpl : Stack {
-    private val frameList = mutableListOf<FrameContainer>()
-    private fun getCurrentFrame() = frameList.last()
-    private var stackCount = 0
-
-    private fun addNewFrame(asSubFrame: Boolean, initPool: List<Variable>, irFunction: IrFunction? = null, irFile: IrFile? = null) {
-        val typeArgumentsPool = initPool.filter { it.symbol is IrTypeParameterSymbol }
-        val valueArguments = initPool.filter { it.symbol !is IrTypeParameterSymbol }
-        val newFrame = InterpreterFrame(valueArguments.toMutableList(), typeArgumentsPool)
-        when {
-            asSubFrame -> getCurrentFrame().addSubFrame(newFrame)
-            else -> frameList.add(FrameContainer(irFile, irFunction, newFrame))
-        }
-    }
-
-    private fun withStackIncrement(asSubFrame: Boolean, block: () -> ExecutionResult): ExecutionResult {
-        return try {
-            stackCount++
-            block()
-        } finally {
-            stackCount--
-            if (asSubFrame) getCurrentFrame().removeSubFrame() else removeLastFrame()
-        }
-    }
-
-    override fun newFrame(asSubFrame: Boolean, initPool: List<Variable>, block: () -> ExecutionResult): ExecutionResult {
-        addNewFrame(asSubFrame, initPool, null, null)
-        return withStackIncrement(asSubFrame, block)
-    }
-
-    override fun newFrame(irFunction: IrFunction, initPool: List<Variable>, block: () -> ExecutionResult): ExecutionResult {
-        val asSubFrame = irFunction.isInline || irFunction.isLocal
-        addNewFrame(asSubFrame, initPool, irFunction, irFunction.fileOrNull)
-        return withStackIncrement(asSubFrame, block)
-    }
-
-    override fun newFrame(irFile: IrFile?, initPool: List<Variable>, block: () -> ExecutionResult): ExecutionResult {
-        addNewFrame(false, initPool, null, irFile)
-        return withStackIncrement(false, block)
-    }
-
-    private fun removeLastFrame() {
-        if (frameList.size > 1 && getCurrentFrame().hasReturnValue()) frameList[frameList.lastIndex - 1].pushReturnValue(getCurrentFrame())
-        frameList.removeAt(frameList.lastIndex)
-    }
-
-    override fun fixCallEntryPoint(irExpression: IrExpression) {
-        val fileEntry = getCurrentFrame().irFile?.fileEntry ?: return
-        val lineNum = fileEntry.getLineNumber(irExpression.startOffset) + 1
-        getCurrentFrame().lineNumber = lineNum
-    }
-
-    override fun getStackTrace(): List<String> {
-        // TODO implement some sort of cache
-        return frameList.map { it.toString() }
-    }
-
-    override fun getCurrentStackInfo(): String {
-        val frame = getCurrentFrame()
-        frame.irFile ?: return "Not defined"
-        val lineNum = if (frame.lineNumber != -1) ":${frame.lineNumber}" else ""
-        return "${frame.irFile.name}$lineNum"
-    }
-
-    override fun getStackCount(): Int = stackCount
-
-    override fun clean(rootFile: IrFile?) {
-        stackCount = 0
-        frameList.clear()
-        frameList.add(FrameContainer(rootFile))
-    }
-
-    override fun addVar(variable: Variable) {
-        getCurrentFrame().addVar(variable)
-    }
-
-    override fun addAll(variables: List<Variable>) {
-        getCurrentFrame().addAll(variables)
-    }
-
-    override fun getVariable(symbol: IrSymbol): Variable {
-        return getCurrentFrame().getVariable(symbol)
-    }
-
-    override fun getAll(): List<Variable> {
-        return getCurrentFrame().getAll()
-    }
-
-    override fun contains(symbol: IrSymbol): Boolean {
-        return getCurrentFrame().contains(symbol)
-    }
-
-    override fun hasReturnValue(): Boolean {
-        return getCurrentFrame().hasReturnValue()
-    }
-
-    override fun pushReturnValue(state: State) {
-        getCurrentFrame().pushReturnValue(state)
-    }
-
-    override fun popReturnValue(): State {
-        return getCurrentFrame().popReturnValue()
-    }
-
-    override fun peekReturnValue(): State {
-        return getCurrentFrame().peekReturnValue()
-    }
-}
-
-private class FrameContainer(val irFile: IrFile? = null, private val entryPoint: IrFunction? = null, current: Frame = InterpreterFrame()) {
-    var lineNumber: Int = -1
-    private val innerStack = mutableListOf(current)
-    private fun getTopFrame() = innerStack.first()
-
-    fun addSubFrame(frame: Frame) {
-        innerStack.add(0, frame)
-    }
-
-    fun removeSubFrame() {
-        if (getTopFrame().hasReturnValue() && innerStack.size > 1) innerStack[1].pushReturnValue(getTopFrame())
-        innerStack.removeAt(0)
-    }
-
-    fun addVar(variable: Variable) = getTopFrame().addVar(variable)
-    fun addAll(variables: List<Variable>) = getTopFrame().addAll(variables)
-    fun getAll() = innerStack.flatMap { it.getAll() }
-    fun getVariable(symbol: IrSymbol): Variable {
-        return innerStack.firstNotNullOfOrNull { it.getVariable(symbol) }
-            ?: throw InterpreterError("$symbol not found") // TODO better message
-    }
-
-    fun contains(symbol: IrSymbol) = innerStack.any { it.contains(symbol) }
-    fun hasReturnValue() = getTopFrame().hasReturnValue()
-    fun pushReturnValue(container: FrameContainer) = getTopFrame().pushReturnValue(container.getTopFrame())
-    fun pushReturnValue(state: State) = getTopFrame().pushReturnValue(state)
-    fun popReturnValue() = getTopFrame().popReturnValue()
-    fun peekReturnValue() = getTopFrame().peekReturnValue()
-
-    override fun toString(): String {
-        irFile ?: return "Not defined"
-        val fileNameCapitalized = irFile.name.replace(".kt", "Kt").capitalize()
-        val lineNum = if (lineNumber != -1) ":$lineNumber" else ""
-        return "at $fileNameCapitalized.${entryPoint?.fqNameWhenAvailable ?: "<clinit>"}(${irFile.name}$lineNum)"
-    }
-}
@@ -12,7 +12,8 @@ import org.jetbrains.kotlin.ir.interpreter.stack.Variable
 import org.jetbrains.kotlin.ir.util.fqNameForIrSerialization
 import org.jetbrains.kotlin.ir.util.nameForIrSerialization

-internal class Common private constructor(override val irClass: IrClass, override val fields: MutableList<Variable>) : Complex {
+internal class Common private constructor(override val irClass: IrClass, override val fields: MutableList<Variable>) : Complex, StateWithClosure {
+    override val upValues: MutableList<Variable> = mutableListOf()
    override var superWrapperClass: Wrapper? = null
    override var outerClass: Variable? = null

@@ -17,8 +17,8 @@ import kotlin.math.min

 internal class ExceptionState private constructor(
    override val irClass: IrClass, override val fields: MutableList<Variable>, stackTrace: List<String>
-) : Complex, Throwable() {
-
+) : Complex, StateWithClosure, Throwable() {
+    override val upValues: MutableList<Variable> = mutableListOf()
    override var superWrapperClass: Wrapper? = null
    override var outerClass: Variable? = null

@@ -9,7 +9,8 @@ import org.jetbrains.kotlin.ir.interpreter.stack.Variable
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.expressions.IrCall
-import org.jetbrains.kotlin.ir.interpreter.exceptions.throwAsUserException
+import org.jetbrains.kotlin.ir.interpreter.IrInterpreterEnvironment
+import org.jetbrains.kotlin.ir.interpreter.handleUserException
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.defaultType
@@ -64,11 +65,12 @@ internal fun State.isSubtypeOf(other: IrType): Boolean {
 * This method used to check if for not null parameter there was passed null argument.
 */
 internal fun State.checkNullability(
-    irType: IrType?, throwException: () -> Nothing = { NullPointerException().throwAsUserException() }
-): State {
+    irType: IrType?, environment: IrInterpreterEnvironment, exceptionToThrow: () -> Throwable = { NullPointerException() }
+): State? {
    if (irType !is IrSimpleType) return this
    if (this.isNull() && !irType.isNullable()) {
-        throwException()
+        exceptionToThrow().handleUserException(environment)
+        return null
    }
    return this
 }
@@ -0,0 +1,12 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.ir.interpreter.state
+
+import org.jetbrains.kotlin.ir.interpreter.stack.Variable
+
+internal interface StateWithClosure {
+    val upValues: MutableList<Variable>
+}
@@ -7,25 +7,23 @@ package org.jetbrains.kotlin.ir.interpreter.state.reflection

 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrFunction
-import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.descriptors.IrAbstractFunctionFactory
 import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrFunctionReference
 import org.jetbrains.kotlin.ir.interpreter.IrInterpreter
-import org.jetbrains.kotlin.ir.interpreter.getLastOverridden
 import org.jetbrains.kotlin.ir.interpreter.proxy.reflection.KParameterProxy
 import org.jetbrains.kotlin.ir.interpreter.proxy.reflection.KTypeParameterProxy
 import org.jetbrains.kotlin.ir.interpreter.proxy.reflection.KTypeProxy
 import org.jetbrains.kotlin.ir.interpreter.stack.Variable
+import org.jetbrains.kotlin.ir.interpreter.state.StateWithClosure
 import org.jetbrains.kotlin.ir.types.classOrNull
-import org.jetbrains.kotlin.ir.util.nameForIrSerialization
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.utils.addToStdlib.cast
 import kotlin.reflect.KParameter
 import kotlin.reflect.KType
 import kotlin.reflect.KTypeParameter

-internal class KFunctionState(val irFunction: IrFunction, override val irClass: IrClass) : ReflectionState() {
+internal class KFunctionState(val irFunction: IrFunction, override val irClass: IrClass) : ReflectionState(), StateWithClosure {
+    override val upValues: MutableList<Variable> = mutableListOf()
    override val fields: MutableList<Variable> = mutableListOf()
    private var _parameters: List<KParameter>? = null
    private var _returnType: KType? = null