IrTypes: migrate some code from backend.common

(cherry picked from commit 3788130)

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/CheckIrElementVisitor.kt

@@ -22,10 +22,11 @@ import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
+import org.jetbrains.kotlin.ir.types.makeNullable
+import org.jetbrains.kotlin.ir.types.toKotlinType
 import org.jetbrains.kotlin.ir.util.isAnnotationClass
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.typeUtil.makeNullable
 
 typealias ReportError = (element: IrElement, message: String) -> Unit
 
@@ -43,8 +44,9 @@ class CheckIrElementVisitor(val builtIns: KotlinBuiltIns, val reportError: Repor
     }
 
     private fun IrExpression.ensureTypeIs(expectedType: KotlinType) {
-        if (expectedType != type) {
-            reportError(this, "unexpected expression.type: expected $expectedType, got ${type}")
+        // TODO: compare IR types instead.
+        if (expectedType != type.toKotlinType()) {
+            reportError(this, "unexpected expression.type: expected $expectedType, got ${type.toKotlinType()}")
         }
     }
 
@@ -154,9 +156,9 @@ class CheckIrElementVisitor(val builtIns: KotlinBuiltIns, val reportError: Repor
             IrTypeOperator.IMPLICIT_CAST,
             IrTypeOperator.IMPLICIT_NOTNULL,
             IrTypeOperator.IMPLICIT_COERCION_TO_UNIT,
-            IrTypeOperator.IMPLICIT_INTEGER_COERCION -> typeOperand
+            IrTypeOperator.IMPLICIT_INTEGER_COERCION -> typeOperand.toKotlinType()
 
-            IrTypeOperator.SAFE_CAST -> typeOperand.makeNullable()
+            IrTypeOperator.SAFE_CAST -> typeOperand.makeNullable().toKotlinType()
 
             IrTypeOperator.INSTANCEOF, IrTypeOperator.NOT_INSTANCEOF -> builtIns.booleanType
         }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/DeepCopyIrTreeWithDeclarations.kt

@@ -21,6 +21,7 @@ import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.expressions.IrLoop
 import org.jetbrains.kotlin.ir.util.DeepCopySymbolRemapper
+import org.jetbrains.kotlin.ir.util.DeepCopyTypeRemapper
 import org.jetbrains.kotlin.ir.util.DescriptorsRemapper
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 
@@ -41,8 +42,10 @@ fun <T : IrElement> T.deepCopyWithVariables(): T {
     val symbolsRemapper = DeepCopySymbolRemapper(descriptorsRemapper)
     acceptVoid(symbolsRemapper)
 
+    val typesRemapper = DeepCopyTypeRemapper(symbolsRemapper)
+
     return this.transform(
-            object : DeepCopyIrTreeWithReturnableBlockSymbols(symbolsRemapper) {
+            object : DeepCopyIrTreeWithReturnableBlockSymbols(symbolsRemapper, typesRemapper) {
                 override fun getNonTransformedLoop(irLoop: IrLoop): IrLoop {
                     return irLoop
                 }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/DumpIrTreeWithDescriptorsVisitor.kt

@@ -5,6 +5,7 @@ import org.jetbrains.kotlin.descriptors.ReceiverParameterDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.util.render
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.renderer.*
 import org.jetbrains.kotlin.types.KotlinType
@@ -285,7 +286,7 @@ class DumpIrTreeWithDescriptorsVisitor(out: Appendable): IrElementVisitor<Unit,
         for (typeParameter in expression.descriptor.original.typeParameters) {
             val typeArgument = expression.getTypeArgument(typeParameter) ?: continue
             val renderedParameter = DescriptorRenderer.ONLY_NAMES_WITH_SHORT_TYPES.render(typeParameter)
-            val renderedType = DescriptorRenderer.ONLY_NAMES_WITH_SHORT_TYPES.renderType(typeArgument)
+            val renderedType = typeArgument.render()
             printer.println("$renderedParameter: $renderedType")
         }
     }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/IrCopy.kt

@@ -25,10 +25,12 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrReturnableBlockImpl
 import org.jetbrains.kotlin.ir.symbols.IrReturnableBlockSymbol
 import org.jetbrains.kotlin.ir.util.DeepCopyIrTreeWithSymbols
 import org.jetbrains.kotlin.ir.util.SymbolRemapper
+import org.jetbrains.kotlin.ir.util.TypeRemapper
 
 open class DeepCopyIrTreeWithReturnableBlockSymbols(
-        private val symbolRemapper: SymbolRemapper
-) : DeepCopyIrTreeWithSymbols(symbolRemapper) {
+    symbolRemapper: SymbolRemapper,
+    typeRemapper: TypeRemapper
+) : DeepCopyIrTreeWithSymbols(symbolRemapper, typeRemapper) {
 
     private inline fun <reified T : IrElement> T.transform() =
             transform(this@DeepCopyIrTreeWithReturnableBlockSymbols, null) as T

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/ir/IrUtils.kt

@@ -16,7 +16,6 @@
 
 package org.jetbrains.kotlin.backend.common.ir
 
-import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.DumpIrTreeWithDescriptorsVisitor
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.annotations.Annotations
@@ -26,14 +25,12 @@ import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrConstructor
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
-import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.expressions.impl.IrBlockBodyImpl
 import org.jetbrains.kotlin.ir.expressions.impl.*
-import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
 import org.jetbrains.kotlin.ir.util.DumpIrTreeVisitor
-import org.jetbrains.kotlin.ir.util.createParameterDeclarations
-import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.TypeProjectionImpl
-import org.jetbrains.kotlin.types.TypeSubstitutor
+import org.jetbrains.kotlin.ir.util.defaultType
 import java.io.StringWriter
 
 
@@ -77,75 +74,62 @@ fun FunctionDescriptor.createOverriddenDescriptor(owner: ClassDescriptor, final:
     }
 }
 
-fun ClassDescriptor.createSimpleDelegatingConstructorDescriptor(
-    superConstructorDescriptor: ClassConstructorDescriptor,
-    isPrimary: Boolean = false
-)
-        : ClassConstructorDescriptor {
-    val constructorDescriptor = ClassConstructorDescriptorImpl.createSynthesized(
-        /* containingDeclaration = */ this,
-        /* annotations           = */ Annotations.EMPTY,
-        /* isPrimary             = */ isPrimary,
-        /* source                = */ SourceElement.NO_SOURCE
-    )
-    val valueParameters = superConstructorDescriptor.valueParameters.map {
-        it.copy(constructorDescriptor, it.name, it.index)
-    }
-    constructorDescriptor.initialize(valueParameters, superConstructorDescriptor.visibility)
-    constructorDescriptor.returnType = superConstructorDescriptor.returnType
-    return constructorDescriptor
-}
-
 fun IrClass.addSimpleDelegatingConstructor(
-    superConstructorSymbol: IrConstructorSymbol,
-    constructorDescriptor: ClassConstructorDescriptor,
-    origin: IrDeclarationOrigin
-)
-        : IrConstructor {
+        superConstructor: IrConstructor,
+        irBuiltIns: IrBuiltIns,
+        origin: IrDeclarationOrigin,
+        isPrimary: Boolean = false
+): IrConstructor {
+    val superConstructorDescriptor = superConstructor.descriptor
+    val constructorDescriptor = ClassConstructorDescriptorImpl.createSynthesized(
+            /* containingDeclaration = */ this.descriptor,
+            /* annotations           = */ Annotations.EMPTY,
+            /* isPrimary             = */ isPrimary,
+            /* source                = */ SourceElement.NO_SOURCE
+    )
+    val valueParameters = superConstructor.valueParameters.map {
+        val descriptor = it.descriptor as ValueParameterDescriptor
+        val newDescriptor = descriptor.copy(constructorDescriptor, descriptor.name, descriptor.index)
+        IrValueParameterImpl(
+                startOffset,
+                endOffset,
+                IrDeclarationOrigin.DEFINED,
+                newDescriptor,
+                it.type,
+                it.varargElementType
+        )
+    }
+
+
+    constructorDescriptor.initialize(
+            valueParameters.map { it.descriptor as ValueParameterDescriptor },
+            superConstructorDescriptor.visibility
+    )
+    constructorDescriptor.returnType = superConstructorDescriptor.returnType
 
     return IrConstructorImpl(startOffset, endOffset, origin, constructorDescriptor).also { constructor ->
-        constructor.createParameterDeclarations()
+
+        assert(superConstructor.dispatchReceiverParameter == null) // Inner classes aren't supported.
+
+        constructor.valueParameters += valueParameters
+        constructor.returnType = this.defaultType
 
         constructor.body = IrBlockBodyImpl(
-            startOffset, endOffset,
-            listOf(
-                IrDelegatingConstructorCallImpl(
-                    startOffset, endOffset,
-                    superConstructorSymbol, superConstructorSymbol.descriptor
-                ).apply {
-                    constructor.valueParameters.forEachIndexed { idx, parameter ->
-                        putValueArgument(idx, IrGetValueImpl(startOffset, endOffset, parameter.symbol))
-                    }
-                },
-                IrInstanceInitializerCallImpl(startOffset, endOffset, this.symbol)
-            )
+                startOffset, endOffset,
+                listOf(
+                        IrDelegatingConstructorCallImpl(
+                                startOffset, endOffset, irBuiltIns.unitType,
+                                superConstructor.symbol, superConstructor.descriptor
+                        ).apply {
+                            constructor.valueParameters.forEachIndexed { idx, parameter ->
+                                putValueArgument(idx, IrGetValueImpl(startOffset, endOffset, parameter.type, parameter.symbol))
+                            }
+                        },
+                        IrInstanceInitializerCallImpl(startOffset, endOffset, this.symbol, irBuiltIns.unitType)
+                )
         )
 
         constructor.parent = this
         this.declarations.add(constructor)
     }
 }
-
-fun CommonBackendContext.createArrayOfExpression(
-    arrayElementType: KotlinType,
-    arrayElements: List<IrExpression>,
-    startOffset: Int, endOffset: Int
-): IrExpression {
-
-    val genericArrayOfFunSymbol = ir.symbols.arrayOf
-    val genericArrayOfFun = genericArrayOfFunSymbol.descriptor
-    val typeParameter0 = genericArrayOfFun.typeParameters[0]
-    val typeSubstitutor = TypeSubstitutor.create(mapOf(typeParameter0.typeConstructor to TypeProjectionImpl(arrayElementType)))
-    val substitutedArrayOfFun = genericArrayOfFun.substitute(typeSubstitutor)!!
-
-    val typeArguments = mapOf(typeParameter0 to arrayElementType)
-
-    val valueParameter0 = substitutedArrayOfFun.valueParameters[0]
-    val arg0VarargType = valueParameter0.type
-    val arg0VarargElementType = valueParameter0.varargElementType!!
-    val arg0 = IrVarargImpl(startOffset, endOffset, arg0VarargType, arg0VarargElementType, arrayElements)
-
-    return IrCallImpl(startOffset, endOffset, genericArrayOfFunSymbol, substitutedArrayOfFun, typeArguments).apply {
-        putValueArgument(0, arg0)
-    }
-}

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/DefaultArgumentStubGenerator.kt

@@ -21,7 +21,6 @@ import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.DeclarationContainerLoweringPass
 import org.jetbrains.kotlin.backend.common.descriptors.synthesizedName
 import org.jetbrains.kotlin.backend.common.ir.ir2string
-import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.descriptors.annotations.Annotations
 import org.jetbrains.kotlin.descriptors.impl.ClassConstructorDescriptorImpl
@@ -33,8 +32,8 @@ import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
 import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrVariableImpl
-import org.jetbrains.kotlin.ir.descriptors.IrTemporaryVariableDescriptorImpl
+import org.jetbrains.kotlin.ir.declarations.impl.IrTypeParameterImpl
+import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
@@ -42,18 +41,13 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrDelegatingConstructorCallImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetObjectValueImpl
 import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
-import org.jetbrains.kotlin.ir.symbols.IrValueSymbol
-import org.jetbrains.kotlin.ir.symbols.IrVariableSymbol
-import org.jetbrains.kotlin.ir.symbols.impl.IrVariableSymbolImpl
+import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.calls.components.hasDefaultValue
 import org.jetbrains.kotlin.resolve.calls.components.isVararg
-import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
-import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.typeUtil.builtIns
 
 open class DefaultArgumentStubGenerator constructor(val context: CommonBackendContext, private val skipInlineMethods: Boolean = true) :
     DeclarationContainerLoweringPass {
@@ -82,34 +76,31 @@ open class DefaultArgumentStubGenerator constructor(val context: CommonBackendCo
         log { "detected ${functionDescriptor.name.asString()} has got #${bodies.size} default expressions" }
         functionDescriptor.overriddenDescriptors.forEach { context.log { "DEFAULT-REPLACER: $it" } }
         if (bodies.isNotEmpty()) {
-            val newIrFunction = functionDescriptor.generateDefaultsFunction(context)
+            val newIrFunction = irFunction.generateDefaultsFunction(context)
             newIrFunction.parent = irFunction.parent
             val descriptor = newIrFunction.descriptor
             log { "$functionDescriptor -> $descriptor" }
             val builder = context.createIrBuilder(newIrFunction.symbol)
             newIrFunction.body = builder.irBlockBody(newIrFunction) {
-                val params = mutableListOf<IrVariableSymbol>()
-                val variables = mutableMapOf<ValueDescriptor, IrValueSymbol>()
+                val params = mutableListOf<IrVariable>()
+                val variables = mutableMapOf<ValueDescriptor, IrValueDeclaration>()
 
                 irFunction.dispatchReceiverParameter?.let {
-                    variables[it.descriptor] = newIrFunction.dispatchReceiverParameter!!.symbol
+                    variables[it.descriptor] = newIrFunction.dispatchReceiverParameter!!
                 }
 
                 if (descriptor.extensionReceiverParameter != null) {
                     variables[functionDescriptor.extensionReceiverParameter!!] =
-                            newIrFunction.extensionReceiverParameter!!.symbol
+                            newIrFunction.extensionReceiverParameter!!
                 }
 
                 for (valueParameter in functionDescriptor.valueParameters) {
-                    val parameterSymbol = newIrFunction.valueParameters[valueParameter.index].symbol
-                    val temporaryVariableSymbol =
-                        IrVariableSymbolImpl(scope.createTemporaryVariableDescriptor(parameterSymbol.descriptor))
-                    params.add(temporaryVariableSymbol)
-                    variables.put(valueParameter, temporaryVariableSymbol)
-                    if (valueParameter.hasDefaultValue()) {
-                        val kIntAnd = symbols.intAnd
+                    val parameter = newIrFunction.valueParameters[valueParameter.index]
+
+                    val argument = if (valueParameter.hasDefaultValue()) {
+                        val kIntAnd = symbols.intAnd.owner
                         val condition = irNotEquals(irCall(kIntAnd).apply {
-                            dispatchReceiver = irGet(maskParameterSymbol(newIrFunction, valueParameter.index / 32))
+                            dispatchReceiver = irGet(maskParameter(newIrFunction, valueParameter.index / 32))
                             putValueArgument(0, irInt(1 shl (valueParameter.index % 32)))
                         }, irInt(0))
                         val expressionBody = getDefaultParameterExpressionBody(irFunction, valueParameter)
@@ -122,41 +113,40 @@ open class DefaultArgumentStubGenerator constructor(val context: CommonBackendCo
                                 return irGet(valueSymbol)
                             }
                         })
-                        val variableInitialization = irIfThenElse(
-                            type = temporaryVariableSymbol.descriptor.type,
+                        irIfThenElse(
+                            type = parameter.type,
                             condition = condition,
                             thenPart = expressionBody.expression,
-                            elsePart = irGet(parameterSymbol)
-                        )
-                        +scope.createTemporaryVariable(
-                            symbol = temporaryVariableSymbol,
-                            initializer = variableInitialization
+                            elsePart = irGet(parameter)
                         )
+
                         /* Mapping calculated values with its origin variables. */
                     } else {
-                        +scope.createTemporaryVariable(
-                            symbol = temporaryVariableSymbol,
-                            initializer = irGet(parameterSymbol)
-                        )
+                        irGet(parameter)
                     }
+                    val temporaryVariable = irTemporary(argument, nameHint = parameter.name.asString())
+
+                    params.add(temporaryVariable)
+                    variables.put(valueParameter, temporaryVariable)
                 }
                 if (irFunction is IrConstructor) {
                     +IrDelegatingConstructorCallImpl(
                         startOffset = irFunction.startOffset,
                         endOffset = irFunction.endOffset,
+                        type = context.irBuiltIns.unitType,
                         symbol = irFunction.symbol, descriptor = irFunction.symbol.descriptor
                     ).apply {
                         params.forEachIndexed { i, variable ->
                             putValueArgument(i, irGet(variable))
                         }
                         if (functionDescriptor.dispatchReceiverParameter != null) {
-                            dispatchReceiver = irGet(newIrFunction.dispatchReceiverParameter!!.symbol)
+                            dispatchReceiver = irGet(newIrFunction.dispatchReceiverParameter!!)
                         }
                     }
                 } else {
-                    +irReturn(irCall(irFunction.symbol).apply {
+                    +irReturn(irCall(irFunction).apply {
                         if (functionDescriptor.dispatchReceiverParameter != null) {
-                            dispatchReceiver = irGet(newIrFunction.dispatchReceiverParameter!!.symbol)
+                            dispatchReceiver = irGet(newIrFunction.dispatchReceiverParameter!!)
                         }
                         if (functionDescriptor.extensionReceiverParameter != null) {
                             extensionReceiver = irGet(variables[functionDescriptor.extensionReceiverParameter!!]!!)
@@ -181,50 +171,29 @@ open class DefaultArgumentStubGenerator constructor(val context: CommonBackendCo
     private fun log(msg: () -> String) = context.log { "DEFAULT-REPLACER: ${msg()}" }
 }
 
-private fun Scope.createTemporaryVariableDescriptor(parameterDescriptor: ParameterDescriptor?): VariableDescriptor =
-    IrTemporaryVariableDescriptorImpl(
-        containingDeclaration = this.scopeOwner,
-        name = parameterDescriptor!!.name.asString().synthesizedName,
-        outType = parameterDescriptor.type,
-        isMutable = false
-    )
-
-private fun Scope.createTemporaryVariable(symbol: IrVariableSymbol, initializer: IrExpression) =
-    IrVariableImpl(
-        startOffset = initializer.startOffset,
-        endOffset = initializer.endOffset,
-        origin = IrDeclarationOrigin.IR_TEMPORARY_VARIABLE,
-        symbol = symbol
-    ).apply {
-
-        this.initializer = initializer
-    }
-
 private fun getDefaultParameterExpressionBody(irFunction: IrFunction, valueParameter: ValueParameterDescriptor): IrExpressionBody {
     return irFunction.getDefault(valueParameter) ?: TODO("FIXME!!!")
 }
 
 private fun maskParameterDescriptor(function: IrFunction, number: Int) =
-    maskParameterSymbol(function, number).descriptor as ValueParameterDescriptor
+    maskParameter(function, number).descriptor as ValueParameterDescriptor
 
-private fun maskParameterSymbol(function: IrFunction, number: Int) =
-    function.valueParameters.single { it.descriptor.name == parameterMaskName(number) }.symbol
+private fun maskParameter(function: IrFunction, number: Int) =
+    function.valueParameters.single { it.descriptor.name == parameterMaskName(number) }
 
 private fun markerParameterDescriptor(descriptor: FunctionDescriptor) =
     descriptor.valueParameters.single { it.name == kConstructorMarkerName }
 
-private fun nullConst(expression: IrElement, type: KotlinType): IrExpression? {
-    when {
-        KotlinBuiltIns.isFloat(type) -> return IrConstImpl.float(expression.startOffset, expression.endOffset, type, 0.0F)
-        KotlinBuiltIns.isDouble(type) -> return IrConstImpl.double(expression.startOffset, expression.endOffset, type, 0.0)
-        KotlinBuiltIns.isBoolean(type) -> return IrConstImpl.boolean(expression.startOffset, expression.endOffset, type, false)
-        KotlinBuiltIns.isByte(type) -> return IrConstImpl.byte(expression.startOffset, expression.endOffset, type, 0)
-        KotlinBuiltIns.isChar(type) -> return IrConstImpl.char(expression.startOffset, expression.endOffset, type, 0.toChar())
-        KotlinBuiltIns.isShort(type) -> return IrConstImpl.short(expression.startOffset, expression.endOffset, type, 0)
-        KotlinBuiltIns.isInt(type) -> return IrConstImpl.int(expression.startOffset, expression.endOffset, type, 0)
-        KotlinBuiltIns.isLong(type) -> return IrConstImpl.long(expression.startOffset, expression.endOffset, type, 0)
-        else -> return IrConstImpl.constNull(expression.startOffset, expression.endOffset, type.builtIns.nullableNothingType)
-    }
+private fun nullConst(expression: IrElement, type: IrType, context: CommonBackendContext) = when {
+    type.isFloat() -> IrConstImpl.float(expression.startOffset, expression.endOffset, type, 0.0F)
+    type.isDouble() -> IrConstImpl.double(expression.startOffset, expression.endOffset, type, 0.0)
+    type.isBoolean() -> IrConstImpl.boolean(expression.startOffset, expression.endOffset, type, false)
+    type.isByte() -> IrConstImpl.byte(expression.startOffset, expression.endOffset, type, 0)
+    type.isChar() -> IrConstImpl.char(expression.startOffset, expression.endOffset, type, 0.toChar())
+    type.isShort() -> IrConstImpl.short(expression.startOffset, expression.endOffset, type, 0)
+    type.isInt() -> IrConstImpl.int(expression.startOffset, expression.endOffset, type, 0)
+    type.isLong() -> IrConstImpl.long(expression.startOffset, expression.endOffset, type, 0)
+    else -> IrConstImpl.constNull(expression.startOffset, expression.endOffset, context.irBuiltIns.nothingNType)
 }
 
 class DefaultParameterInjector constructor(val context: CommonBackendContext, private val skipInline: Boolean = true) : BodyLoweringPass {
@@ -240,10 +209,12 @@ class DefaultParameterInjector constructor(val context: CommonBackendContext, pr
                 if (argumentsCount == descriptor.valueParameters.size)
                     return expression
                 val (symbolForCall, params) = parametersForCall(expression)
+                symbolForCall as IrConstructorSymbol
                 return IrDelegatingConstructorCallImpl(
                     startOffset = expression.startOffset,
                     endOffset = expression.endOffset,
-                    symbol = symbolForCall as IrConstructorSymbol,
+                    type = context.irBuiltIns.unitType,
+                    symbol = symbolForCall,
                     descriptor = symbolForCall.descriptor
                 )
                     .apply {
@@ -273,13 +244,14 @@ class DefaultParameterInjector constructor(val context: CommonBackendContext, pr
                 return IrCallImpl(
                     startOffset = expression.startOffset,
                     endOffset = expression.endOffset,
+                    type = symbol.owner.returnType,
                     symbol = symbol,
                     descriptor = descriptor,
-                    typeArguments = expression.descriptor.typeParameters.map {
-                        it to (expression.getTypeArgument(it) ?: it.defaultType)
-                    }.toMap()
+                    typeArgumentsCount = expression.typeArgumentsCount
                 )
                     .apply {
+                        this.copyTypeArgumentsFrom(expression)
+
                         params.forEach {
                             log { "call::params@${it.first.index}/${it.first.name.asString()}: ${ir2string(it.second)}" }
                             putValueArgument(it.first.index, it.second)
@@ -310,8 +282,7 @@ class DefaultParameterInjector constructor(val context: CommonBackendContext, pr
             private fun parametersForCall(expression: IrFunctionAccessExpression): Pair<IrFunctionSymbol, List<Pair<ValueParameterDescriptor, IrExpression?>>> {
                 val descriptor = expression.descriptor
                 val keyFunction = expression.symbol.owner.findSuperMethodWithDefaultArguments()!!
-                val keyDescriptor = keyFunction.descriptor
-                val realFunction = keyDescriptor.generateDefaultsFunction(context)
+                val realFunction = keyFunction.generateDefaultsFunction(context)
                 realFunction.parent = keyFunction.parent
                 val realDescriptor = realFunction.descriptor
 
@@ -325,15 +296,18 @@ class DefaultParameterInjector constructor(val context: CommonBackendContext, pr
                         maskValues[maskIndex] = maskValues[maskIndex] or (1 shl (i % 32))
                     }
                     val valueParameterDescriptor = realDescriptor.valueParameters[i]
-                    val defaultValueArgument =
-                        if (valueParameterDescriptor.isVararg) null else nullConst(expression, valueParameterDescriptor.type)
+                    val defaultValueArgument = if (valueParameterDescriptor.isVararg) {
+                        null
+                    } else {
+                        nullConst(expression, realFunction.valueParameters[i].type, context)
+                    }
                     valueParameterDescriptor to (valueArgument ?: defaultValueArgument)
                 })
                 maskValues.forEachIndexed { i, maskValue ->
                     params += maskParameterDescriptor(realFunction, i) to IrConstImpl.int(
                         startOffset = irBody.startOffset,
                         endOffset = irBody.endOffset,
-                        type = descriptor.builtIns.intType,
+                        type = context.irBuiltIns.intType,
                         value = maskValue
                     )
                 }
@@ -347,7 +321,7 @@ class DefaultParameterInjector constructor(val context: CommonBackendContext, pr
                     )
                 } else if (context.ir.shouldGenerateHandlerParameterForDefaultBodyFun()) {
                     params += realDescriptor.valueParameters.last() to
-                            IrConstImpl.constNull(irBody.startOffset, irBody.endOffset, context.builtIns.any.defaultType)
+                            IrConstImpl.constNull(irBody.startOffset, irBody.endOffset, context.irBuiltIns.anyType)
                 }
                 params.forEach {
                     log { "descriptor::${realDescriptor.name.asString()}#${it.first.index}: ${it.first.name.asString()}" }
@@ -366,7 +340,7 @@ class DefaultParameterInjector constructor(val context: CommonBackendContext, pr
 private fun CallableMemberDescriptor.needsDefaultArgumentsLowering(skipInlineMethods: Boolean) =
     valueParameters.any { it.hasDefaultValue() } && !(this is FunctionDescriptor && isInline && skipInlineMethods)
 
-private fun FunctionDescriptor.generateDefaultsFunction(context: CommonBackendContext): IrFunction {
+private fun IrFunction.generateDefaultsFunction(context: CommonBackendContext): IrFunction = with(this.descriptor) {
     return context.ir.defaultParameterDeclarationsCache.getOrPut(this) {
         val descriptor = when (this) {
             is ClassConstructorDescriptor ->
@@ -389,8 +363,10 @@ private fun FunctionDescriptor.generateDefaultsFunction(context: CommonBackendCo
             }
         }
 
+        val function = this@generateDefaultsFunction
+
         val syntheticParameters = MutableList((valueParameters.size + 31) / 32) { i ->
-            valueParameter(descriptor, valueParameters.size + i, parameterMaskName(i), descriptor.builtIns.intType)
+            valueParameter(descriptor, valueParameters.size + i, parameterMaskName(i), context.irBuiltIns.intType)
         }
         if (this is ClassConstructorDescriptor) {
             syntheticParameters += valueParameter(
@@ -402,10 +378,29 @@ private fun FunctionDescriptor.generateDefaultsFunction(context: CommonBackendCo
             syntheticParameters += valueParameter(
                 descriptor, syntheticParameters.last().index + 1,
                 "handler".synthesizedName,
-                context.ir.symbols.any.owner.defaultType
+                context.irBuiltIns.anyType
             )
         }
 
+        val newValueParameters = function.valueParameters.map {
+            val parameterDescriptor = ValueParameterDescriptorImpl(
+                containingDeclaration = descriptor,
+                original = null, /* ValueParameterDescriptorImpl::copy do not save original. */
+                index = it.index,
+                annotations = it.descriptor.annotations,
+                name = it.name,
+                outType = it.descriptor.type,
+                declaresDefaultValue = false,
+                isCrossinline = it.isCrossinline,
+                isNoinline = it.isNoinline,
+                varargElementType = (it.descriptor as ValueParameterDescriptor).varargElementType,
+                source = it.descriptor.source
+            )
+
+            it.copy(parameterDescriptor)
+
+        } + syntheticParameters
+
         descriptor.initialize(
             /* receiverParameterType         = */ extensionReceiverParameter?.type,
             /* dispatchReceiverParameter     = */ dispatchReceiverParameter,
@@ -425,24 +420,11 @@ private fun FunctionDescriptor.generateDefaultsFunction(context: CommonBackendCo
                     setInitialized()
                 }
             },
-            /* unsubstitutedValueParameters  = */ valueParameters.map {
-                ValueParameterDescriptorImpl(
-                    containingDeclaration = descriptor,
-                    original = null, /* ValueParameterDescriptorImpl::copy do not save original. */
-                    index = it.index,
-                    annotations = it.annotations,
-                    name = it.name,
-                    outType = it.type,
-                    declaresDefaultValue = false,
-                    isCrossinline = it.isCrossinline,
-                    isNoinline = it.isNoinline,
-                    varargElementType = it.varargElementType,
-                    source = it.source
-                )
-            } + syntheticParameters,
+            /* unsubstitutedValueParameters  = */ newValueParameters.map { it.descriptor as ValueParameterDescriptor },
             /* unsubstitutedReturnType       = */ returnType,
             /* modality                      = */ Modality.FINAL,
-            /* visibility                    = */ this.visibility)
+            /* visibility                    = */ this.visibility
+        )
         descriptor.isSuspend = this.isSuspend
         context.log { "adds to cache[$this] = $descriptor" }
 
@@ -463,7 +445,29 @@ private fun FunctionDescriptor.generateDefaultsFunction(context: CommonBackendCo
             )
         }
 
-        result.createParameterDeclarations()
+        result.returnType = function.returnType
+
+        function.typeParameters.mapTo(result.typeParameters) {
+            assert(function.descriptor.typeParameters[it.index] == it.descriptor)
+            IrTypeParameterImpl(
+                startOffset, endOffset, origin, descriptor.typeParameters[it.index]
+            ).apply { this.superTypes += it.superTypes }
+        }
+        result.parent = function.parent
+        result.createDispatchReceiverParameter()
+
+        function.extensionReceiverParameter?.let {
+            result.extensionReceiverParameter = IrValueParameterImpl(
+                it.startOffset,
+                it.endOffset,
+                it.origin,
+                descriptor.extensionReceiverParameter!!,
+                it.type,
+                it.varargElementType
+            ).apply { parent = result }
+        }
+
+        result.valueParameters += newValueParameters.also { it.forEach { it.parent = result } }
 
         result
     }
@@ -472,20 +476,28 @@ private fun FunctionDescriptor.generateDefaultsFunction(context: CommonBackendCo
 object DECLARATION_ORIGIN_FUNCTION_FOR_DEFAULT_PARAMETER :
     IrDeclarationOriginImpl("DEFAULT_PARAMETER_EXTENT")
 
-private fun valueParameter(descriptor: FunctionDescriptor, index: Int, name: Name, type: KotlinType): ValueParameterDescriptor {
-    return ValueParameterDescriptorImpl(
+private fun IrFunction.valueParameter(descriptor: FunctionDescriptor, index: Int, name: Name, type: IrType): IrValueParameter {
+    val parameterDescriptor = ValueParameterDescriptorImpl(
         containingDeclaration = descriptor,
         original = null,
         index = index,
         annotations = Annotations.EMPTY,
         name = name,
-        outType = type,
+        outType = type.toKotlinType(),
         declaresDefaultValue = false,
         isCrossinline = false,
         isNoinline = false,
         varargElementType = null,
         source = SourceElement.NO_SOURCE
     )
+    return IrValueParameterImpl(
+        startOffset,
+        endOffset,
+        IrDeclarationOrigin.DEFINED,
+        parameterDescriptor,
+        type,
+        null
+    )
 }
 
 internal val kConstructorMarkerName = "marker".synthesizedName

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/InitializersLowering.kt

@@ -68,7 +68,7 @@ class InitializersLowering(
                 if (declaration.descriptor.dispatchReceiverParameter != null) // TODO isStaticField
                     IrGetValueImpl(
                         irFieldInitializer.startOffset, irFieldInitializer.endOffset,
-                        irClass.thisReceiver!!.symbol
+                        irClass.thisReceiver!!.type, irClass.thisReceiver!!.symbol
                     )
                 else null
             val irSetField = IrSetFieldImpl(
@@ -76,6 +76,7 @@ class InitializersLowering(
                 declaration.symbol,
                 receiver,
                 irFieldInitializer,
+                context.irBuiltIns.unitType,
                 null, null
             )
 
@@ -93,7 +94,7 @@ class InitializersLowering(
         fun transformInstanceInitializerCallsInConstructors(irClass: IrClass) {
             irClass.transformChildrenVoid(object : IrElementTransformerVoid() {
                 override fun visitInstanceInitializerCall(expression: IrInstanceInitializerCall): IrExpression {
-                    return IrBlockImpl(irClass.startOffset, irClass.endOffset, context.builtIns.unitType, null,
+                    return IrBlockImpl(irClass.startOffset, irClass.endOffset, context.irBuiltIns.unitType, null,
                                        instanceInitializerStatements.map { it.copy(irClass) })
                 }
             })

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/IrBuildUtils.kt

@@ -16,26 +16,8 @@
 
 package org.jetbrains.kotlin.backend.common.lower
 
-import org.jetbrains.kotlin.backend.common.BackendContext
-import org.jetbrains.kotlin.descriptors.*
-import org.jetbrains.kotlin.descriptors.annotations.Annotations
-import org.jetbrains.kotlin.descriptors.impl.PropertyDescriptorImpl
-import org.jetbrains.kotlin.descriptors.impl.PropertyGetterDescriptorImpl
-import org.jetbrains.kotlin.descriptors.impl.PropertySetterDescriptorImpl
-import org.jetbrains.kotlin.descriptors.impl.ValueParameterDescriptorImpl
-import org.jetbrains.kotlin.ir.builders.*
-import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFieldImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrPropertyImpl
-import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
-import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
+import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
-import org.jetbrains.kotlin.ir.symbols.impl.IrFieldSymbolImpl
-import org.jetbrains.kotlin.ir.symbols.impl.IrSimpleFunctionSymbolImpl
-import org.jetbrains.kotlin.ir.util.createParameterDeclarations
-import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.types.KotlinType
 
 abstract class SymbolWithIrBuilder<out S: IrSymbol, out D: IrDeclaration> {
 
@@ -62,155 +44,3 @@ abstract class SymbolWithIrBuilder<out S: IrSymbol, out D: IrDeclaration> {
             return builtIr
         }
 }
-
-fun BackendContext.createPropertyGetterBuilder(startOffset: Int, endOffset: Int, origin: IrDeclarationOrigin,
-                                               fieldSymbol: IrFieldSymbol, type: KotlinType)
-        = object: SymbolWithIrBuilder<IrSimpleFunctionSymbol, IrSimpleFunction>() {
-
-    override fun buildSymbol() = IrSimpleFunctionSymbolImpl(
-            PropertyGetterDescriptorImpl(
-                    /* correspondingProperty = */ fieldSymbol.descriptor,
-                    /* annotations           = */ Annotations.EMPTY,
-                    /* modality              = */ Modality.FINAL,
-                    /* visibility            = */ Visibilities.PRIVATE,
-                    /* isDefault             = */ false,
-                    /* isExternal            = */ false,
-                    /* isInline              = */ false,
-                    /* kind                  = */ CallableMemberDescriptor.Kind.DECLARATION,
-                    /* original              = */ null,
-                    /* source                = */ SourceElement.NO_SOURCE
-            )
-    )
-
-    override fun doInitialize() {
-        val descriptor = symbol.descriptor as PropertyGetterDescriptorImpl
-        descriptor.apply {
-            initialize(type)
-        }
-    }
-
-    override fun buildIr() = IrFunctionImpl(
-            startOffset = startOffset,
-            endOffset   = endOffset,
-            origin      = origin,
-            symbol      = symbol).apply {
-
-        createParameterDeclarations()
-
-        body = createIrBuilder(this.symbol, startOffset, endOffset).irBlockBody {
-            +irReturn(irGetField(irGet(this@apply.dispatchReceiverParameter!!.symbol), fieldSymbol))
-        }
-    }
-}
-
-private fun BackendContext.createPropertySetterBuilder(startOffset: Int, endOffset: Int, origin: IrDeclarationOrigin,
-                                                       fieldSymbol: IrFieldSymbol, type: KotlinType)
-        = object: SymbolWithIrBuilder<IrSimpleFunctionSymbol, IrSimpleFunction>() {
-
-    override fun buildSymbol() = IrSimpleFunctionSymbolImpl(
-            PropertySetterDescriptorImpl(
-                    /* correspondingProperty = */ fieldSymbol.descriptor,
-                    /* annotations           = */ Annotations.EMPTY,
-                    /* modality              = */ Modality.FINAL,
-                    /* visibility            = */ Visibilities.PRIVATE,
-                    /* isDefault             = */ false,
-                    /* isExternal            = */ false,
-                    /* isInline              = */ false,
-                    /* kind                  = */ CallableMemberDescriptor.Kind.DECLARATION,
-                    /* original              = */ null,
-                    /* source                = */ SourceElement.NO_SOURCE
-            )
-    )
-
-    lateinit var valueParameterDescriptor: ValueParameterDescriptor
-
-    override fun doInitialize() {
-        val descriptor = symbol.descriptor as PropertySetterDescriptorImpl
-        descriptor.apply {
-            valueParameterDescriptor = ValueParameterDescriptorImpl(
-                    containingDeclaration = this,
-                    original              = null,
-                    index                 = 0,
-                    annotations           = Annotations.EMPTY,
-                    name                  = Name.identifier("value"),
-                    outType               = type,
-                    declaresDefaultValue  = false,
-                    isCrossinline         = false,
-                    isNoinline            = false,
-                    varargElementType     = null,
-                    source                = SourceElement.NO_SOURCE
-            )
-
-            initialize(valueParameterDescriptor)
-        }
-    }
-
-    override fun buildIr() = IrFunctionImpl(
-            startOffset = startOffset,
-            endOffset   = endOffset,
-            origin      = origin,
-            symbol      = symbol).apply {
-
-        createParameterDeclarations()
-
-        body = createIrBuilder(this.symbol, startOffset, endOffset).irBlockBody {
-            +irSetField(irGet(this@apply.dispatchReceiverParameter!!.symbol), fieldSymbol, irGet(this@apply.valueParameters.single().symbol))
-        }
-    }
-}
-
-fun BackendContext.createPropertyWithBackingFieldBuilder(startOffset: Int, endOffset: Int, origin: IrDeclarationOrigin,
-                                                         owner: ClassDescriptor, name: Name, type: KotlinType, isMutable: Boolean)
-        = object: SymbolWithIrBuilder<IrFieldSymbol, IrProperty>() {
-
-    private lateinit var getterBuilder: SymbolWithIrBuilder<IrSimpleFunctionSymbol, IrSimpleFunction>
-    private var setterBuilder: SymbolWithIrBuilder<IrSimpleFunctionSymbol, IrSimpleFunction>? = null
-
-    override fun buildSymbol() = IrFieldSymbolImpl(
-            PropertyDescriptorImpl.create(
-                    /* containingDeclaration = */ owner,
-                    /* annotations           = */ Annotations.EMPTY,
-                    /* modality              = */ Modality.FINAL,
-                    /* visibility            = */ Visibilities.PRIVATE,
-                    /* isVar                 = */ isMutable,
-                    /* name                  = */ name,
-                    /* kind                  = */ CallableMemberDescriptor.Kind.DECLARATION,
-                    /* source                = */ SourceElement.NO_SOURCE,
-                    /* lateInit              = */ false,
-                    /* isConst               = */ false,
-                    /* isExpect              = */ false,
-                    /* isActual                = */ false,
-                    /* isExternal            = */ false,
-                    /* isDelegated           = */ false
-            )
-    )
-
-    override fun doInitialize() {
-        val descriptor = symbol.descriptor as PropertyDescriptorImpl
-        getterBuilder = createPropertyGetterBuilder(startOffset, endOffset, origin, symbol, type).apply { initialize() }
-        if (isMutable)
-            setterBuilder = createPropertySetterBuilder(startOffset, endOffset, origin, symbol, type).apply { initialize() }
-        descriptor.initialize(
-                /* getter = */ getterBuilder.symbol.descriptor as PropertyGetterDescriptorImpl,
-                /* setter = */ setterBuilder?.symbol?.descriptor as? PropertySetterDescriptorImpl)
-        val receiverType: KotlinType? = null
-        descriptor.setType(type, emptyList(), owner.thisAsReceiverParameter, receiverType)
-    }
-
-    override fun buildIr(): IrProperty {
-        val backingField = IrFieldImpl(
-                startOffset = startOffset,
-                endOffset   = endOffset,
-                origin      = origin,
-                symbol      = symbol)
-        return IrPropertyImpl(
-                startOffset  = startOffset,
-                endOffset    = endOffset,
-                origin       = origin,
-                isDelegated  = false,
-                descriptor   = symbol.descriptor,
-                backingField = backingField,
-                getter       = getterBuilder.ir,
-                setter       = setterBuilder?.ir)
-    }
-}

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/KCallableNamePropertyLowering.kt

@@ -58,7 +58,7 @@ private class KCallableNamePropertyTransformer(val lower: KCallableNamePropertyL
 
         return lower.context.createIrBuilder(expression.symbol, expression.startOffset, expression.endOffset).run {
 
-            IrCompositeImpl(startOffset, endOffset, context.builtIns.stringType).apply {
+            IrCompositeImpl(startOffset, endOffset, context.irBuiltIns.stringType).apply {
                 receiver?.let {
                     //put receiver for bound callable reference
                     statements.add(it)
@@ -68,7 +68,7 @@ private class KCallableNamePropertyTransformer(val lower: KCallableNamePropertyL
                     IrConstImpl.string(
                         expression.startOffset,
                         expression.endOffset,
-                        context.builtIns.stringType,
+                        context.irBuiltIns.stringType,
                         callableReference.descriptor.name.asString()
                     )
                 )

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LateinitLowering.kt

@@ -27,6 +27,8 @@ import org.jetbrains.kotlin.ir.expressions.IrBlock
 import org.jetbrains.kotlin.ir.expressions.impl.IrBlockImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.types.isPrimitiveType
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.types.KotlinType
@@ -45,20 +47,20 @@ class LateinitLowering(
 
             private fun transformGetter(backingField: IrField, getter: IrFunction) {
                 val type = backingField.type
-                assert(!KotlinBuiltIns.isPrimitiveType(type)) { "'lateinit' modifier is not allowed on primitive types" }
+                assert(!type.isPrimitiveType()) { "'lateinit' modifier is not allowed on primitive types" }
                 val startOffset = getter.startOffset
                 val endOffset = getter.endOffset
                 val irBuilder = context.createIrBuilder(getter.symbol, startOffset, endOffset)
                 irBuilder.run {
                     val block = irBlock(type)
                     val resultVar = scope.createTemporaryVariable(
-                        irGetField(getter.dispatchReceiverParameter?.let { irGet(it.symbol) }, backingField.symbol)
+                        irGetField(getter.dispatchReceiverParameter?.let { irGet(it) }, backingField)
                     )
                     block.statements.add(resultVar)
                     val throwIfNull = irIfThenElse(
-                        context.builtIns.nothingType,
-                        irNotEquals(irGet(resultVar.symbol), irNull()),
-                        irReturn(irGet(resultVar.symbol)),
+                        context.irBuiltIns.nothingType,
+                        irNotEquals(irGet(resultVar), irNull()),
+                        irReturn(irGet(resultVar)),
                         throwUninitializedPropertyAccessException(backingField)
                     )
                     block.statements.add(throwIfNull)
@@ -76,15 +78,15 @@ class LateinitLowering(
                     IrConstImpl.string(
                         UNDEFINED_OFFSET,
                         UNDEFINED_OFFSET,
-                        context.builtIns.stringType,
+                        context.irBuiltIns.stringType,
                         backingField.name.asString()
                     )
                 )
             }
         }
 
-    private val throwErrorFunction = context.ir.symbols.ThrowUninitializedPropertyAccessException
+    private val throwErrorFunction = context.ir.symbols.ThrowUninitializedPropertyAccessException.owner
 
-    private fun IrBuilderWithScope.irBlock(type: KotlinType): IrBlock = IrBlockImpl(startOffset, endOffset, type)
+    private fun IrBuilderWithScope.irBlock(type: IrType): IrBlock = IrBlockImpl(startOffset, endOffset, type)
 
 }

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalDeclarationsLowering.kt

@@ -34,7 +34,6 @@ import org.jetbrains.kotlin.ir.visitors.*
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.descriptorUtil.parents
 import org.jetbrains.kotlin.resolve.descriptorUtil.parentsWithSelf
-import org.jetbrains.kotlin.types.KotlinType
 import java.util.*
 
 interface LocalNameProvider {
@@ -98,12 +97,12 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
         abstract val transformedDescriptor: FunctionDescriptor
         abstract val transformedDeclaration: IrFunction
 
-        val capturedValueToParameter: MutableMap<ValueDescriptor, IrValueParameterSymbol> = HashMap()
+        val capturedValueToParameter: MutableMap<ValueDescriptor, IrValueParameter> = HashMap()
 
         override fun irGet(startOffset: Int, endOffset: Int, descriptor: ValueDescriptor): IrExpression? {
-            val newSymbol = capturedValueToParameter[descriptor] ?: return null
+            val parameter = capturedValueToParameter[descriptor] ?: return null
 
-            return IrGetValueImpl(startOffset, endOffset, newSymbol)
+            return IrGetValueImpl(startOffset, endOffset, parameter.type, parameter.symbol)
         }
     }
 
@@ -141,9 +140,10 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
         override fun irGet(startOffset: Int, endOffset: Int, descriptor: ValueDescriptor): IrExpression? {
             val field = capturedValueToField[descriptor] ?: return null
 
+            val receiver = declaration.thisReceiver!!
             return IrGetFieldImpl(
-                startOffset, endOffset, field.symbol,
-                receiver = IrGetValueImpl(startOffset, endOffset, declaration.thisReceiver!!.symbol)
+                startOffset, endOffset, field.symbol, field.type,
+                receiver = IrGetValueImpl(startOffset, endOffset, receiver.type, receiver.symbol)
             )
         }
 
@@ -155,9 +155,10 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
         override fun irGet(startOffset: Int, endOffset: Int, descriptor: ValueDescriptor): IrExpression? {
             val field = classContext.capturedValueToField[descriptor] ?: return null
 
+            val receiver = member.dispatchReceiverParameter!!
             return IrGetFieldImpl(
-                startOffset, endOffset, field.symbol,
-                receiver = IrGetValueImpl(startOffset, endOffset, member.dispatchReceiverParameter!!.symbol)
+                startOffset, endOffset, field.symbol, field.type,
+                receiver = IrGetValueImpl(startOffset, endOffset, receiver.type, receiver.symbol)
             )
         }
 
@@ -168,12 +169,12 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
         val localClasses: MutableMap<ClassDescriptor, LocalClassContext> = LinkedHashMap()
         val localClassConstructors: MutableMap<ClassConstructorDescriptor, LocalClassConstructorContext> = LinkedHashMap()
 
-        val transformedDeclarations = mutableMapOf<DeclarationDescriptor, IrSymbol>()
+        val transformedDeclarations = mutableMapOf<DeclarationDescriptor, IrDeclaration>()
 
-        val FunctionDescriptor.transformed: IrFunctionSymbol?
-            get() = transformedDeclarations[this] as IrFunctionSymbol?
+        val FunctionDescriptor.transformed: IrFunction?
+            get() = transformedDeclarations[this] as IrFunction?
 
-        val oldParameterToNew: MutableMap<ParameterDescriptor, IrValueParameterSymbol> = HashMap()
+        val oldParameterToNew: MutableMap<ParameterDescriptor, IrValueParameter> = HashMap()
         val newParameterToOld: MutableMap<ParameterDescriptor, ParameterDescriptor> = HashMap()
         val newParameterToCaptured: MutableMap<ValueParameterDescriptor, IrValueSymbol> = HashMap()
 
@@ -200,7 +201,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
 
                         original.descriptor.valueParameters.filter { it.declaresDefaultValue() }.forEach { argument ->
                             val body = original.getDefault(argument)!!
-                            oldParameterToNew[argument]!!.owner.defaultValue = body
+                            oldParameterToNew[argument]!!.defaultValue = body
                         }
                     }
                 }
@@ -218,7 +219,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             override fun visitClass(declaration: IrClass): IrStatement {
                 if (declaration.descriptor in localClasses) {
                     // Replace local class definition with an empty composite.
-                    return IrCompositeImpl(declaration.startOffset, declaration.endOffset, context.builtIns.unitType)
+                    return IrCompositeImpl(declaration.startOffset, declaration.endOffset, context.irBuiltIns.unitType)
                 } else {
                     return super.visitClass(declaration)
                 }
@@ -227,7 +228,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             override fun visitFunction(declaration: IrFunction): IrStatement {
                 if (declaration.descriptor in localFunctions) {
                     // Replace local function definition with an empty composite.
-                    return IrCompositeImpl(declaration.startOffset, declaration.endOffset, context.builtIns.unitType)
+                    return IrCompositeImpl(declaration.startOffset, declaration.endOffset, context.irBuiltIns.unitType)
                 } else {
                     if (localContext is LocalClassContext && declaration.parent == localContext.declaration) {
                         return declaration.apply {
@@ -250,7 +251,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
 
                         declaration.descriptor.valueParameters.filter { it.declaresDefaultValue() }.forEach { argument ->
                             val body = declaration.getDefault(argument)!!
-                            oldParameterToNew[argument]!!.owner.defaultValue = body
+                            oldParameterToNew[argument]!!.defaultValue = body
                         }
                     }
                 } else {
@@ -266,7 +267,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 }
 
                 oldParameterToNew[descriptor]?.let {
-                    return IrGetValueImpl(expression.startOffset, expression.endOffset, it)
+                    return IrGetValueImpl(expression.startOffset, expression.endOffset, it.type, it.symbol)
                 }
 
                 return expression
@@ -287,14 +288,17 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 expression.transformChildrenVoid(this)
 
                 val oldCallee = expression.descriptor.original
-                val newCallee = transformedDeclarations[oldCallee] as IrConstructorSymbol? ?: return expression
+                val newCallee = transformedDeclarations[oldCallee] as IrConstructor? ?: return expression
 
                 return IrDelegatingConstructorCallImpl(
                     expression.startOffset, expression.endOffset,
-                    newCallee,
-                    newCallee.descriptor,
-                    remapTypeArguments(expression, newCallee.descriptor)
-                ).fillArguments(expression)
+                    context.irBuiltIns.unitType,
+                    newCallee.symbol,
+                    newCallee.descriptor
+                ).also {
+                    it.fillArguments(expression)
+                    it.copyTypeArgumentsFrom(expression)
+                }
             }
 
             private fun <T : IrMemberAccessExpression> T.fillArguments(oldExpression: IrMemberAccessExpression): T {
@@ -310,16 +314,17 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                             newParameterToCaptured[newValueParameterDescriptor]
                                     ?: throw AssertionError("Non-mapped parameter $newValueParameterDescriptor")
 
+                        val capturedValue = capturedValueSymbol.owner
+
                         val capturedValueDescriptor = capturedValueSymbol.descriptor
                         localContext?.irGet(
                             oldExpression.startOffset, oldExpression.endOffset,
                             capturedValueDescriptor
-                        ) ?:
-                        // Captured value is directly available for the caller.
-                        IrGetValueImpl(
-                            oldExpression.startOffset, oldExpression.endOffset,
-                            oldParameterToNew[capturedValueDescriptor] ?: capturedValueSymbol
-                        )
+                        ) ?: run {
+                            // Captured value is directly available for the caller.
+                            val value = oldParameterToNew[capturedValueDescriptor] ?: capturedValue
+                            IrGetValueImpl(oldExpression.startOffset, oldExpression.endOffset, value.type, value.symbol)
+                        }
                     }
 
                 }
@@ -339,11 +344,14 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 val newCallableReference = IrFunctionReferenceImpl(
                     expression.startOffset, expression.endOffset,
                     expression.type, // TODO functional type for transformed descriptor
-                    newCallee,
+                    newCallee.symbol,
                     newCallee.descriptor,
-                    remapTypeArguments(expression, newCallee.descriptor),
+                    expression.typeArgumentsCount,
                     expression.origin
-                ).fillArguments(expression)
+                ).also {
+                    it.fillArguments(expression)
+                    it.copyTypeArgumentsFrom(expression)
+                }
 
                 return newCallableReference
             }
@@ -354,7 +362,11 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 val oldReturnTarget = expression.returnTarget
                 val newReturnTarget = oldReturnTarget.transformed ?: return expression
 
-                return IrReturnImpl(expression.startOffset, expression.endOffset, newReturnTarget, expression.value)
+                return IrReturnImpl(
+                    expression.startOffset, expression.endOffset,
+                    context.irBuiltIns.nothingType,
+                    newReturnTarget.symbol, expression.value
+                )
             }
 
             override fun visitDeclarationReference(expression: IrDeclarationReference): IrExpression {
@@ -398,8 +410,10 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                         0,
                         IrSetFieldImpl(
                             startOffset, endOffset, field.symbol,
-                            IrGetValueImpl(startOffset, endOffset, irClass.thisReceiver!!.symbol),
-                            capturedValueExpression, STATEMENT_ORIGIN_INITIALIZER_OF_FIELD_FOR_CAPTURED_VALUE
+                            IrGetValueImpl(startOffset, endOffset, irClass.thisReceiver!!.type, irClass.thisReceiver!!.symbol),
+                            capturedValueExpression,
+                            context.irBuiltIns.unitType,
+                            STATEMENT_ORIGIN_INITIALIZER_OF_FIELD_FOR_CAPTURED_VALUE
                         )
                     )
                 }
@@ -422,31 +436,19 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             rewriteFunctionBody(memberDeclaration, null)
         }
 
-        private fun createNewCall(oldCall: IrCall, newCallee: IrFunctionSymbol) =
+        private fun createNewCall(oldCall: IrCall, newCallee: IrFunction) =
             if (oldCall is IrCallWithShallowCopy)
-                oldCall.shallowCopy(oldCall.origin, newCallee, oldCall.superQualifierSymbol)
+                oldCall.shallowCopy(oldCall.origin, newCallee.symbol, oldCall.superQualifierSymbol)
             else
                 IrCallImpl(
                     oldCall.startOffset, oldCall.endOffset,
-                    newCallee,
+                    newCallee.returnType,
+                    newCallee.symbol,
                     newCallee.descriptor,
-                    remapTypeArguments(oldCall, newCallee.descriptor),
                     oldCall.origin, oldCall.superQualifierSymbol
-                )
-
-        private fun remapTypeArguments(
-            oldExpression: IrMemberAccessExpression,
-            newCallee: CallableDescriptor
-        ): Map<TypeParameterDescriptor, KotlinType>? {
-            val oldCallee = oldExpression.descriptor.original
-
-            return if (oldCallee.typeParameters.isEmpty())
-                null
-            else oldCallee.typeParameters.associateBy(
-                { newCallee.typeParameters[it.index] },
-                { oldExpression.getTypeArgumentOrDefault(it) }
-            )
-        }
+                ).also {
+                    it.copyTypeArgumentsFrom(oldCall)
+                }
 
         private fun transformDescriptors() {
             localFunctions.values.forEach {
@@ -519,7 +521,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 oldDescriptor.extensionReceiverParameter?.type,
                 newDispatchReceiverParameter,
                 newTypeParameters,
-                newValueParameters,
+                newValueParameters.map { it.descriptor as ValueParameterDescriptor },
                 oldDescriptor.returnType,
                 Modality.FINAL,
                 Visibilities.PRIVATE
@@ -533,9 +535,26 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 IrFunctionImpl(startOffset, endOffset, origin, newDescriptor)
             }.apply {
                 parent = memberDeclaration.parent
-                createParameterDeclarations()
+                returnType = localFunctionContext.declaration.returnType
+
+                localFunctionContext.declaration.typeParameters.mapTo(this.typeParameters) {
+                    IrTypeParameterImpl(it.startOffset, it.endOffset, it.origin, it.descriptor)
+                        .apply { superTypes += it.superTypes }
+                }
+
+                localFunctionContext.declaration.extensionReceiverParameter?.let {
+                    this.extensionReceiverParameter = IrValueParameterImpl(
+                        it.startOffset,
+                        it.endOffset,
+                        it.origin,
+                        descriptor.extensionReceiverParameter!!,
+                        it.type,
+                        null
+                    )
+                }
+                this.valueParameters += newValueParameters
                 recordTransformedValueParameters(localFunctionContext)
-                transformedDeclarations[oldDescriptor] = this.symbol
+                transformedDeclarations[oldDescriptor] = this
             }
         }
 
@@ -543,7 +562,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             localContext: LocalContextWithClosureAsParameters,
             capturedValues: List<IrValueSymbol>
         )
-                : List<ValueParameterDescriptor> {
+                : List<IrValueParameter> {
 
             val oldDescriptor = localContext.descriptor
             val newDescriptor = localContext.transformedDescriptor
@@ -551,17 +570,23 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             val closureParametersCount = capturedValues.size
             val newValueParametersCount = closureParametersCount + oldDescriptor.valueParameters.size
 
-            val newValueParameters = ArrayList<ValueParameterDescriptor>(newValueParametersCount).apply {
+            val newValueParameters = ArrayList<IrValueParameter>(newValueParametersCount).apply {
                 capturedValues.mapIndexedTo(this) { i, capturedValue ->
-                    createUnsubstitutedCapturedValueParameter(newDescriptor, capturedValue.descriptor, i).apply {
+                    val parameterDescriptor = createUnsubstitutedCapturedValueParameter(newDescriptor, capturedValue.descriptor, i).apply {
                         newParameterToCaptured[this] = capturedValue
                     }
+                    capturedValue.owner.copy(parameterDescriptor)
                 }
 
-                oldDescriptor.valueParameters.mapIndexedTo(this) { i, oldValueParameterDescriptor ->
-                    createUnsubstitutedParameter(newDescriptor, oldValueParameterDescriptor, closureParametersCount + i).apply {
-                        newParameterToOld.putAbsentOrSame(this, oldValueParameterDescriptor)
+                localContext.declaration.valueParameters.mapIndexedTo(this) { i, oldValueParameter ->
+                    val parameterDescriptor = createUnsubstitutedParameter(
+                        newDescriptor,
+                        oldValueParameter.descriptor as ValueParameterDescriptor,
+                        closureParametersCount + i
+                    ).apply {
+                        newParameterToOld.putAbsentOrSame(this, oldValueParameter.descriptor)
                     }
+                    oldValueParameter.copy(parameterDescriptor)
                 }
             }
             return newValueParameters
@@ -572,14 +597,14 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             valueParameters.forEach {
                 val capturedValue = newParameterToCaptured[it.descriptor]
                 if (capturedValue != null) {
-                    localContext.capturedValueToParameter[capturedValue.descriptor] = it.symbol
+                    localContext.capturedValueToParameter[capturedValue.descriptor] = it
                 }
             }
 
             (listOfNotNull(dispatchReceiverParameter, extensionReceiverParameter) + valueParameters).forEach {
                 val oldParameter = newParameterToOld[it.descriptor]
                 if (oldParameter != null) {
-                    oldParameterToNew.putAbsentOrSame(oldParameter, it.symbol)
+                    oldParameterToNew.putAbsentOrSame(oldParameter, it)
                 }
             }
 
@@ -603,7 +628,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             val newValueParameters = createTransformedValueParameters(constructorContext, capturedValues)
 
             newDescriptor.initialize(
-                newValueParameters,
+                newValueParameters.map { it.descriptor as ValueParameterDescriptor },
                 Visibilities.PRIVATE,
                 newTypeParameters
             )
@@ -618,12 +643,23 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
             }
 
             constructorContext.transformedDeclaration = with(constructorContext.declaration) {
-                IrConstructorImpl(startOffset, endOffset, origin, newDescriptor)
+                IrConstructorImpl(startOffset, endOffset, origin, newDescriptor).also { it.returnType = returnType }
             }.apply {
                 parent = constructorContext.declaration.parent
-                createParameterDeclarations()
+                constructorContext.declaration.dispatchReceiverParameter?.let {
+                    this.dispatchReceiverParameter = IrValueParameterImpl(
+                        it.startOffset,
+                        it.endOffset,
+                        it.origin,
+                        descriptor.dispatchReceiverParameter!!,
+                        it.type,
+                        null
+                    )
+                }
+
+                this.valueParameters += newValueParameters
                 recordTransformedValueParameters(constructorContext)
-                transformedDeclarations[oldDescriptor] = this.symbol
+                transformedDeclarations[oldDescriptor] = this
             }
         }
 
@@ -662,7 +698,7 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
                 localClassContext.capturedValueToField[capturedValue.descriptor] = IrFieldImpl(
                     localClassContext.declaration.startOffset, localClassContext.declaration.endOffset,
                     DECLARATION_ORIGIN_FIELD_FOR_CAPTURED_VALUE,
-                    fieldDescriptor
+                    fieldDescriptor, capturedValue.owner.type
                 ).apply {
                     parent = localClassContext.declaration
                 }
@@ -775,4 +811,13 @@ class LocalDeclarationsLowering(val context: BackendContext, val localNameProvid
         }
     }
 
-}
+}
+
+private fun IrValueDeclaration.copy(newDescriptor: ParameterDescriptor): IrValueParameter = IrValueParameterImpl(
+    startOffset,
+    endOffset,
+    IrDeclarationOrigin.DEFINED,
+    newDescriptor,
+    type,
+    (this as? IrValueParameter)?.varargElementType
+)

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LowerUtils.kt

@@ -30,6 +30,7 @@ import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
+import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
@@ -60,7 +61,7 @@ abstract class AbstractVariableRemapper : IrElementTransformerVoid() {
 
     override fun visitGetValue(expression: IrGetValue): IrExpression =
         remapVariable(expression.descriptor)?.let {
-            IrGetValueImpl(expression.startOffset, expression.endOffset, it.symbol, expression.origin)
+            IrGetValueImpl(expression.startOffset, expression.endOffset, it.type, it.symbol, expression.origin)
         } ?: expression
 }
 
@@ -84,7 +85,7 @@ fun <T : IrBuilder> T.at(element: IrElement) = this.at(element.startOffset, elem
  */
 inline fun IrGeneratorWithScope.irBlock(
     expression: IrExpression, origin: IrStatementOrigin? = null,
-    resultType: KotlinType? = expression.type,
+    resultType: IrType? = expression.type,
     body: IrBlockBuilder.() -> Unit
 ) =
     this.irBlock(expression.startOffset, expression.endOffset, origin, resultType, body)
@@ -93,13 +94,15 @@ inline fun IrGeneratorWithScope.irBlockBody(irElement: IrElement, body: IrBlockB
     this.irBlockBody(irElement.startOffset, irElement.endOffset, body)
 
 fun IrBuilderWithScope.irIfThen(condition: IrExpression, thenPart: IrExpression) =
-    IrIfThenElseImpl(startOffset, endOffset, context.builtIns.unitType, condition, thenPart, null)
+    IrIfThenElseImpl(startOffset, endOffset, context.irBuiltIns.unitType).apply {
+        branches += IrBranchImpl(condition, thenPart)
+    }
 
 fun IrBuilderWithScope.irNot(arg: IrExpression) =
     primitiveOp1(startOffset, endOffset, context.irBuiltIns.booleanNotSymbol, IrStatementOrigin.EXCL, arg)
 
 fun IrBuilderWithScope.irThrow(arg: IrExpression) =
-    IrThrowImpl(startOffset, endOffset, context.builtIns.nothingType, arg)
+    IrThrowImpl(startOffset, endOffset, context.irBuiltIns.nothingType, arg)
 
 fun IrBuilderWithScope.irCatch(catchParameter: IrVariable) =
     IrCatchImpl(
@@ -107,21 +110,12 @@ fun IrBuilderWithScope.irCatch(catchParameter: IrVariable) =
         catchParameter
     )
 
-fun IrBuilderWithScope.irCast(arg: IrExpression, type: KotlinType, typeOperand: KotlinType) =
-    IrTypeOperatorCallImpl(startOffset, endOffset, type, IrTypeOperator.CAST, typeOperand, arg)
-
 fun IrBuilderWithScope.irImplicitCoercionToUnit(arg: IrExpression) =
     IrTypeOperatorCallImpl(
-        startOffset, endOffset, context.builtIns.unitType,
-        IrTypeOperator.IMPLICIT_COERCION_TO_UNIT, context.builtIns.unitType, arg
+        startOffset, endOffset, context.irBuiltIns.unitType,
+        IrTypeOperator.IMPLICIT_COERCION_TO_UNIT, context.irBuiltIns.unitType, context.irBuiltIns.unitClass, arg
     )
 
-fun IrBuilderWithScope.irGetField(receiver: IrExpression, symbol: IrFieldSymbol) =
-    IrGetFieldImpl(startOffset, endOffset, symbol, receiver)
-
-fun IrBuilderWithScope.irSetField(receiver: IrExpression, symbol: IrFieldSymbol, value: IrExpression) =
-    IrSetFieldImpl(startOffset, endOffset, symbol, receiver, value)
-
 open class IrBuildingTransformer(private val context: BackendContext) : IrElementTransformerVoid() {
     private var currentBuilder: IrBuilderWithScope? = null
 

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/StringConcatenationLowering.kt

@@ -27,10 +27,12 @@ import org.jetbrains.kotlin.ir.builders.irGet
 import org.jetbrains.kotlin.ir.builders.irTemporary
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.declarations.IrSymbolDeclaration
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrStringConcatenation
-import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
+import org.jetbrains.kotlin.ir.types.isNullableAny
+import org.jetbrains.kotlin.ir.types.toKotlinType
 import org.jetbrains.kotlin.ir.util.constructors
 import org.jetbrains.kotlin.ir.util.functions
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
@@ -60,33 +62,33 @@ private class StringConcatenationTransformer(val lower: StringConcatenationLower
     private val nameToString = Name.identifier("toString")
     private val nameAppend = Name.identifier("append")
 
-    private val stringBuilder = context.ir.symbols.stringBuilder
+    private val stringBuilder = context.ir.symbols.stringBuilder.owner
 
     //TODO: calculate and pass string length to the constructor.
     private val constructor = stringBuilder.constructors.single {
-        it.owner.valueParameters.size == 0
+        it.valueParameters.size == 0
     }
 
     private val toStringFunction = stringBuilder.functions.single {
-        it.owner.valueParameters.size == 0 && it.descriptor.name == nameToString
+        it.valueParameters.size == 0 && it.name == nameToString
     }
     private val defaultAppendFunction = stringBuilder.functions.single {
         it.descriptor.name == nameAppend &&
-                it.owner.valueParameters.size == 1 &&
-                it.owner.valueParameters.single().type == builtIns.nullableAnyType
+                it.valueParameters.size == 1 &&
+                it.valueParameters.single().type.isNullableAny()
     }
 
 
-    private val appendFunctions: Map<KotlinType, IrFunctionSymbol?> =
+    private val appendFunctions: Map<KotlinType, IrSimpleFunction?> =
         typesWithSpecialAppendFunction.map { type ->
             type to stringBuilder.functions.toList().atMostOne {
                 it.descriptor.name == nameAppend &&
-                        it.owner.valueParameters.size == 1 &&
-                        it.owner.valueParameters.single().type == type
+                        it.valueParameters.size == 1 &&
+                        it.valueParameters.single().type.toKotlinType() == type
             }
         }.toMap()
 
-    private fun typeToAppendFunction(type: KotlinType): IrFunctionSymbol {
+    private fun typeToAppendFunction(type: KotlinType): IrSimpleFunction {
         return appendFunctions[type] ?: defaultAppendFunction
     }
 
@@ -96,9 +98,9 @@ private class StringConcatenationTransformer(val lower: StringConcatenationLower
         expression.transformChildrenVoid(this)
         val blockBuilder = buildersStack.last()
         return blockBuilder.irBlock(expression) {
-            val stringBuilderImpl = irTemporary(irCall(constructor)).symbol
+            val stringBuilderImpl = irTemporary(irCall(constructor))
             expression.arguments.forEach { arg ->
-                val appendFunction = typeToAppendFunction(arg.type)
+                val appendFunction = typeToAppendFunction(arg.type.toKotlinType())
                 +irCall(appendFunction).apply {
                     dispatchReceiver = irGet(stringBuilderImpl)
                     putValueArgument(0, arg)

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/TailrecLowering.kt

@@ -18,14 +18,12 @@ package org.jetbrains.kotlin.backend.common.lower
 
 import org.jetbrains.kotlin.backend.common.*
 import org.jetbrains.kotlin.ir.builders.*
-import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
 import org.jetbrains.kotlin.ir.symbols.IrValueParameterSymbol
-import org.jetbrains.kotlin.ir.symbols.IrValueSymbol
-import org.jetbrains.kotlin.ir.symbols.IrVariableSymbol
 import org.jetbrains.kotlin.ir.util.explicitParameters
-import org.jetbrains.kotlin.ir.util.getArgumentsWithSymbols
+import org.jetbrains.kotlin.ir.util.getArgumentsWithIr
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 
@@ -55,7 +53,7 @@ private fun lowerTailRecursionCalls(context: BackendContext, irFunction: IrFunct
     irFunction.body = builder.irBlockBody {
         // Define variables containing current values of parameters:
         val parameterToVariable = parameters.associate {
-            it to irTemporaryVar(irGet(it), nameHint = it.suggestVariableName()).symbol
+            it to irTemporaryVar(irGet(it), nameHint = it.symbol.suggestVariableName())
         }
         // (these variables are to be updated on any tail call).
 
@@ -63,11 +61,11 @@ private fun lowerTailRecursionCalls(context: BackendContext, irFunction: IrFunct
             val loop = this
             condition = irTrue()
 
-            body = irBlock(startOffset, endOffset, resultType = context.builtIns.unitType) {
+            body = irBlock(startOffset, endOffset, resultType = context.irBuiltIns.unitType) {
                 // Read variables containing current values of parameters:
                 val parameterToNew = parameters.associate {
                     val variable = parameterToVariable[it]!!
-                    it to irTemporary(irGet(variable), nameHint = it.suggestVariableName()).symbol
+                    it to irTemporary(irGet(variable), nameHint = it.symbol.suggestVariableName())
                 }
 
                 val transformer = BodyTransformer(
@@ -89,8 +87,8 @@ private class BodyTransformer(
     val builder: IrBuilderWithScope,
     val irFunction: IrFunction,
     val loop: IrLoop,
-    val parameterToNew: Map<IrValueParameterSymbol, IrValueSymbol>,
-    val parameterToVariable: Map<IrValueParameterSymbol, IrVariableSymbol>,
+    val parameterToNew: Map<IrValueParameter, IrValueDeclaration>,
+    val parameterToVariable: Map<IrValueParameter, IrVariable>,
     val tailRecursionCalls: Set<IrCall>
 ) : IrElementTransformerVoid() {
 
@@ -98,7 +96,7 @@ private class BodyTransformer(
 
     override fun visitGetValue(expression: IrGetValue): IrExpression {
         expression.transformChildrenVoid(this)
-        val value = parameterToNew[expression.symbol] ?: return expression
+        val value = parameterToNew[expression.symbol.owner] ?: return expression
         return builder.at(expression).irGet(value)
     }
 
@@ -113,7 +111,7 @@ private class BodyTransformer(
 
     private fun IrBuilderWithScope.genTailCall(expression: IrCall) = this.irBlock(expression) {
         // Get all specified arguments:
-        val parameterToArgument = expression.getArgumentsWithSymbols().map { (parameter, argument) ->
+        val parameterToArgument = expression.getArgumentsWithIr().map { (parameter, argument) ->
             parameter to argument
         }
 
@@ -122,7 +120,7 @@ private class BodyTransformer(
             at(argument)
             // Note that argument can use values of parameters, so it is important that
             // references to parameters are mapped using `parameterToNew`, not `parameterToVariable`.
-            +irSetVar(parameterToVariable[parameter]!!, argument)
+            +irSetVar(parameterToVariable[parameter]!!.symbol, argument)
         }
 
         val specifiedParameters = parameterToArgument.map { (parameter, _) -> parameter }.toSet()
@@ -130,7 +128,7 @@ private class BodyTransformer(
         // For each unspecified argument set the corresponding variable to default:
         parameters.filter { it !in specifiedParameters }.forEach { parameter ->
 
-            val originalDefaultValue = parameter.owner.defaultValue?.expression ?: throw Error("no argument specified for $parameter")
+            val originalDefaultValue = parameter.defaultValue?.expression ?: throw Error("no argument specified for $parameter")
 
             // Copy default value, mapping parameters to variables containing freshly computed arguments:
             val defaultValue = originalDefaultValue
@@ -140,15 +138,15 @@ private class BodyTransformer(
                     override fun visitGetValue(expression: IrGetValue): IrExpression {
                         expression.transformChildrenVoid(this)
 
-                        val variableSymbol = parameterToVariable[expression.symbol] ?: return expression
+                        val variable = parameterToVariable[expression.symbol.owner] ?: return expression
                         return IrGetValueImpl(
-                            expression.startOffset, expression.endOffset,
-                            variableSymbol, expression.origin
+                            expression.startOffset, expression.endOffset, variable.type,
+                            variable.symbol, expression.origin
                         )
                     }
                 }, data = null)
 
-            +irSetVar(parameterToVariable[parameter]!!, defaultValue)
+            +irSetVar(parameterToVariable[parameter]!!.symbol, defaultValue)
         }
 
         // Jump to the entry:

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/VarargLowering.kt

@@ -32,14 +32,10 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrVarargImpl
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
-import org.jetbrains.kotlin.ir.symbols.IrVariableSymbol
-import org.jetbrains.kotlin.ir.util.constructors
-import org.jetbrains.kotlin.ir.util.defaultType
-import org.jetbrains.kotlin.ir.util.functions
-import org.jetbrains.kotlin.ir.util.getPropertyGetter
+import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
-import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.util.OperatorNameConventions
 
 
@@ -68,20 +64,25 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
         element?.transformChildrenVoid(object: IrElementTransformerVoid() {
             val transformer = this
 
-            private fun replaceEmptyParameterWithEmptyArray(expression: IrMemberAccessExpression) {
+            private fun replaceEmptyParameterWithEmptyArray(expression: IrFunctionAccessExpression) {
                 log { "call of: ${expression.descriptor}" }
                 context.createIrBuilder(owner, expression.startOffset, expression.endOffset).apply {
                     expression.descriptor.valueParameters.forEach {
                         log { "varargElementType: ${it.varargElementType} expr: ${ir2string(expression.getValueArgument(it))}" }
                     }
-                    expression.descriptor.valueParameters.filter { it.varargElementType != null && expression.getValueArgument(it) == null }.forEach {
-                        expression.putValueArgument(it.index,
-                                IrVarargImpl(startOffset       = startOffset,
-                                             endOffset         = endOffset,
-                                             type              = it.type,
-                                             varargElementType = it.varargElementType!!)
-                        )
-                    }
+                    expression.symbol.owner.valueParameters
+                        .filter { it.varargElementType != null && expression.getValueArgument(it.index) == null }
+                        .forEach {
+                            expression.putValueArgument(
+                                it.index,
+                                IrVarargImpl(
+                                    startOffset = startOffset,
+                                    endOffset = endOffset,
+                                    type = it.type,
+                                    varargElementType = it.varargElementType!!
+                                )
+                            )
+                        }
                 }
                 expression.transformChildrenVoid(this)
             }
@@ -99,28 +100,27 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
             override fun visitVararg(expression: IrVararg): IrExpression {
                 expression.transformChildrenVoid(transformer)
                 val hasSpreadElement = hasSpreadElement(expression)
-                if (!hasSpreadElement && expression.elements.all { it is IrConst<*> && KotlinBuiltIns.isString(it.type) }) {
+                if (!hasSpreadElement && expression.elements.all { it is IrConst<*> && it.type.isString() }) {
                     log { "skipped vararg expression because it's string array literal" }
                     return expression
                 }
                 val irBuilder = context.createIrBuilder(owner, expression.startOffset, expression.endOffset)
                 irBuilder.run {
                     val type = expression.varargElementType
-                    log { "$expression: array type:$type, is array of primitives ${!KotlinBuiltIns.isArray(expression.type)}" }
+                    log { "$expression: array type:$type, is array of primitives ${!expression.type.isArray()}" }
                     val arrayHandle = arrayType(expression.type)
-                    val arrayConstructor = arrayHandle.arraySymbol.constructors.find { it.owner.valueParameters.size == 1 }!!
-                    val block = irBlock(arrayHandle.arraySymbol.owner.defaultType)
-                    val arrayConstructorCall = if (arrayConstructor.owner.typeParameters.isEmpty()) {
-                        irCall(arrayConstructor)
-                    } else {
-                        irCall(arrayConstructor, listOf(type))
-                    }
+                    val arrayConstructor = arrayHandle.arraySymbol.owner.constructors.find { it.valueParameters.size == 1 }!!
+                    val block = irBlock(expression.type)
+                    val arrayConstructorCall = irCall(arrayConstructor)
 
+                    if (arrayConstructor.typeParameters.isNotEmpty()) {
+                        arrayConstructorCall.putTypeArgument(0, expression.varargElementType)
+                    }
 
                     val vars = expression.elements.map {
                         val initVar = scope.createTemporaryVariable(
-                                (it as? IrSpreadElement)?.expression ?: it as IrExpression,
-                                "elem".synthesizedString, true)
+                            (it as? IrSpreadElement)?.expression ?: it as IrExpression,
+                            "elem".synthesizedString, true)
                         block.statements.add(initVar)
                         it to initVar
                     }.toMap()
@@ -138,32 +138,31 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
                             log { "element:$i> ${ir2string(element)}" }
                             val dst = vars[element]!!
                             if (element !is IrSpreadElement) {
-                                val setArrayElementCall = irCall(arrayHandle.setMethodSymbol)
-                                setArrayElementCall.dispatchReceiver = irGet(arrayTmpVariable.symbol)
-                                setArrayElementCall.putValueArgument(0, if (hasSpreadElement) irGet(indexTmpVariable.symbol) else irConstInt(i))
-                                setArrayElementCall.putValueArgument(1, irGet(dst.symbol))
+                                val setArrayElementCall = irCall(arrayHandle.setMethodSymbol.owner)
+                                setArrayElementCall.dispatchReceiver = irGet(arrayTmpVariable)
+                                setArrayElementCall.putValueArgument(0, if (hasSpreadElement) irGet(indexTmpVariable) else irConstInt(i))
+                                setArrayElementCall.putValueArgument(1, irGet(dst))
                                 block.statements.add(setArrayElementCall)
                                 if (hasSpreadElement) {
-                                    block.statements.add(incrementVariable(indexTmpVariable.symbol, kIntOne))
+                                    block.statements.add(incrementVariable(indexTmpVariable, kIntOne))
                                 }
                             } else {
-                                val arraySizeVariable = scope.createTemporaryVariable(irArraySize(arrayHandle, irGet(dst.symbol)), "length".synthesizedString)
+                                val arraySizeVariable = scope.createTemporaryVariable(irArraySize(arrayHandle, irGet(dst)), "length".synthesizedString)
                                 block.statements.add(arraySizeVariable)
-                                val copyCall = irCall(arrayHandle.copyRangeToSymbol).apply {
-                                    extensionReceiver = irGet(dst.symbol)
-                                    putValueArgument(0, irGet(arrayTmpVariable.symbol))  /* destination */
+                                val copyCall = irCall(arrayHandle.copyRangeToSymbol.owner).apply {
+                                    extensionReceiver = irGet(dst)
+                                    putValueArgument(0, irGet(arrayTmpVariable))  /* destination */
                                     putValueArgument(1, kIntZero)                            /* fromIndex */
-                                    putValueArgument(2, irGet(arraySizeVariable.symbol)) /* toIndex */
-                                    putValueArgument(3, irGet(indexTmpVariable.symbol))  /* destinationIndex */
+                                    putValueArgument(2, irGet(arraySizeVariable)) /* toIndex */
+                                    putValueArgument(3, irGet(indexTmpVariable))  /* destinationIndex */
                                 }
                                 block.statements.add(copyCall)
-                                block.statements.add(incrementVariable(indexTmpVariable.symbol,
-                                        irGet(arraySizeVariable.symbol)))
+                                block.statements.add(incrementVariable(indexTmpVariable, irGet(arraySizeVariable)))
                                 log { "element:$i:spread element> ${ir2string(element.expression)}" }
                             }
                         }
                     }
-                    block.statements.add(irGet(arrayTmpVariable.symbol))
+                    block.statements.add(irGet(arrayTmpVariable))
                     return block
                 }
             }
@@ -171,24 +170,21 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
     }
 
     private val symbols = context.ir.symbols
-    private val intPlusInt = symbols.intPlusInt
+    private val intPlusInt = symbols.intPlusInt.owner
 
-    private fun arrayType(type: KotlinType): ArrayHandle = when {
-        KotlinBuiltIns.isPrimitiveArray(type) -> {
-            val primitiveType = KotlinBuiltIns.getPrimitiveArrayType(type.constructor.declarationDescriptor!!)
-            when (primitiveType) {
-                PrimitiveType.BYTE    -> kByteArrayHandler
-                PrimitiveType.SHORT   -> kShortArrayHandler
-                PrimitiveType.CHAR    -> kCharArrayHandler
-                PrimitiveType.INT     -> kIntArrayHandler
-                PrimitiveType.LONG    -> kLongArrayHandler
-                PrimitiveType.FLOAT   -> kFloatArrayHandler
-                PrimitiveType.DOUBLE  -> kDoubleArrayHandler
-                PrimitiveType.BOOLEAN -> kBooleanArrayHandler
-                else                  -> TODO("unsupported type: $primitiveType")
-            }
+    private fun arrayType(type: IrType): ArrayHandle {
+        val primitiveType = KotlinBuiltIns.getPrimitiveArrayType(type.classifierOrFail.descriptor)
+        return when (primitiveType) {
+            PrimitiveType.BYTE    -> kByteArrayHandler
+            PrimitiveType.SHORT   -> kShortArrayHandler
+            PrimitiveType.CHAR    -> kCharArrayHandler
+            PrimitiveType.INT     -> kIntArrayHandler
+            PrimitiveType.LONG    -> kLongArrayHandler
+            PrimitiveType.FLOAT   -> kFloatArrayHandler
+            PrimitiveType.DOUBLE  -> kDoubleArrayHandler
+            PrimitiveType.BOOLEAN -> kBooleanArrayHandler
+            else                  -> kArrayHandler
         }
-        else -> kArrayHandler
     }
 
     private fun IrBuilderWithScope.intPlus() = irCall(intPlusInt)
@@ -199,9 +195,9 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
         }
     }
 
-    private fun IrBuilderWithScope.incrementVariable(symbol: IrVariableSymbol, value: IrExpression): IrExpression {
-        return irSetVar(symbol, intPlus().apply {
-            dispatchReceiver = irGet(symbol)
+    private fun IrBuilderWithScope.incrementVariable(variable: IrVariable, value: IrExpression): IrExpression {
+        return irSetVar(variable.symbol, intPlus().apply {
+            dispatchReceiver = irGet(variable)
             putValueArgument(0, value)
         })
     }
@@ -212,14 +208,14 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
             val notSpreadElementCount = expression.elements.filter { it !is IrSpreadElement}.size
             val initialValue = irConstInt(notSpreadElementCount) as IrExpression
             return vars.filter{it.key is IrSpreadElement}.toList().fold( initial = initialValue) { result, it ->
-                val arraySize = irArraySize(arrayHandle, irGet(it.second.symbol))
+                val arraySize = irArraySize(arrayHandle, irGet(it.second))
                 increment(result, arraySize)
             }
         }
     }
 
     private fun IrBuilderWithScope.irArraySize(arrayHandle: ArrayHandle, expression: IrExpression): IrExpression {
-        val arraySize = irCall(arrayHandle.sizeGetterSymbol).apply {
+        val arraySize = irCall(arrayHandle.sizeGetterSymbol.owner).apply {
             dispatchReceiver = expression
         }
         return arraySize
@@ -256,7 +252,8 @@ class VarargInjectionLowering constructor(val context: CommonBackendContext): De
 
 }
 
-private fun IrBuilderWithScope.irConstInt(value: Int): IrConst<Int> = IrConstImpl.int(startOffset, endOffset, context.builtIns.intType, value)
-private fun IrBuilderWithScope.irBlock(type: KotlinType): IrBlock = IrBlockImpl(startOffset, endOffset, type)
+private fun IrBuilderWithScope.irConstInt(value: Int): IrConst<Int> =
+    IrConstImpl.int(startOffset, endOffset, context.irBuiltIns.intType, value)
+private fun IrBuilderWithScope.irBlock(type: IrType): IrBlock = IrBlockImpl(startOffset, endOffset, type)
 private val IrBuilderWithScope.kIntZero get() = irConstInt(0)
 private val IrBuilderWithScope.kIntOne get() = irConstInt(1)

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

@@ -16,17 +16,11 @@
 
 package org.jetbrains.kotlin.ir.builders
 
-import org.jetbrains.kotlin.backend.common.descriptors.substitute
-import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
-import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrLoop
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
 import org.jetbrains.kotlin.ir.expressions.impl.*
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
-import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
-import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
-import org.jetbrains.kotlin.ir.util.defaultType
-import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
 
 fun IrBuilderWithScope.irWhile(origin: IrStatementOrigin? = null) =
     IrWhileLoopImpl(startOffset, endOffset, context.irBuiltIns.unitType, origin)
@@ -37,18 +31,5 @@ fun IrBuilderWithScope.irBreak(loop: IrLoop) =
 fun IrBuilderWithScope.irContinue(loop: IrLoop) =
     IrContinueImpl(startOffset, endOffset, context.irBuiltIns.nothingType, loop)
 
-fun IrBuilderWithScope.irTrue() = IrConstImpl.boolean(startOffset, endOffset, context.irBuiltIns.booleanType, true)
-
-fun IrBuilderWithScope.irFalse() = IrConstImpl.boolean(startOffset, endOffset, context.irBuiltIns.booleanType, false)
-
-fun IrBuilderWithScope.irCall(symbol: IrFunctionSymbol, typeArguments: Map<TypeParameterDescriptor, KotlinType>) =
-    IrCallImpl(this.startOffset, this.endOffset, symbol, symbol.descriptor.substitute(typeArguments), typeArguments)
-
-fun IrBuilderWithScope.irCall(symbol: IrFunctionSymbol, typeArguments: List<KotlinType>) =
-    irCall(symbol, symbol.descriptor.typeParameters.zip(typeArguments).toMap())
-
 fun IrBuilderWithScope.irGetObject(classSymbol: IrClassSymbol) =
-    IrGetObjectValueImpl(startOffset, endOffset, classSymbol.owner.defaultType, classSymbol)
-
-fun IrBuilderWithScope.irGetField(receiver: IrExpression?, symbol: IrFieldSymbol) =
-    IrGetFieldImpl(startOffset, endOffset, symbol, receiver)
+    IrGetObjectValueImpl(startOffset, endOffset, IrSimpleTypeImpl(classSymbol, false, emptyList(), emptyList()), classSymbol)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/builders/ExpressionHelpers.kt

@@ -9,6 +9,9 @@ import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.descriptors.VariableDescriptor
 import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.declarations.IrField
+import org.jetbrains.kotlin.ir.declarations.IrFunction
+import org.jetbrains.kotlin.ir.declarations.IrValueDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrVariable
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
@@ -128,9 +131,14 @@ fun IrBuilderWithScope.irIfThenReturnFalse(condition: IrExpression) =
 fun IrBuilderWithScope.irGet(type: IrType, variable: IrValueSymbol) =
     IrGetValueImpl(startOffset, endOffset, type, variable)
 
+fun IrBuilderWithScope.irGet(variable: IrValueDeclaration) = irGet(variable.type, variable.symbol)
+
 fun IrBuilderWithScope.irSetVar(variable: IrVariableSymbol, value: IrExpression) =
     IrSetVariableImpl(startOffset, endOffset, context.irBuiltIns.unitType, variable, value, IrStatementOrigin.EQ)
 
+fun IrBuilderWithScope.irGetField(receiver: IrExpression?, field: IrField) =
+    IrGetFieldImpl(startOffset, endOffset, field.symbol, field.type, receiver)
+
 fun IrBuilderWithScope.irEqeqeq(arg1: IrExpression, arg2: IrExpression) =
     context.eqeqeq(startOffset, endOffset, arg1, arg2)
 
@@ -169,6 +177,9 @@ fun IrBuilderWithScope.irCall(callee: IrFunctionSymbol, type: IrType): IrCall =
 fun IrBuilderWithScope.irCall(callee: IrFunctionSymbol, descriptor: FunctionDescriptor, type: IrType): IrCall =
     IrCallImpl(startOffset, endOffset, type, callee, descriptor)
 
+fun IrBuilderWithScope.irCall(callee: IrFunction): IrCall =
+    irCall(callee.symbol, callee.descriptor, callee.returnType)
+
 
 fun IrBuilderWithScope.irCallOp(
     callee: IrFunctionSymbol,

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/builders/Scope.kt

@@ -31,6 +31,7 @@ import org.jetbrains.kotlin.ir.symbols.impl.IrClassSymbolImpl
 import org.jetbrains.kotlin.ir.symbols.impl.IrFieldSymbolImpl
 import org.jetbrains.kotlin.ir.symbols.impl.createFunctionSymbol
 import org.jetbrains.kotlin.ir.types.impl.originalKotlinType
+import org.jetbrains.kotlin.ir.types.toKotlinType
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.KotlinType
 
@@ -61,7 +62,7 @@ class Scope(val scopeOwnerSymbol: IrSymbol) {
         isMutable: Boolean = false,
         origin: IrDeclarationOrigin = IrDeclarationOrigin.IR_TEMPORARY_VARIABLE
     ): IrVariable {
-        val originalKotlinType = irExpression.type.originalKotlinType ?: throw AssertionError("No originalKotlinType for $irExpression")
+        val originalKotlinType = irExpression.type.originalKotlinType ?: irExpression.type.toKotlinType()
         return IrVariableImpl(
             irExpression.startOffset, irExpression.endOffset, origin,
             createDescriptorForTemporaryVariable(

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypePredicates.kt

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2010-2018 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.types
+
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
+import org.jetbrains.kotlin.name.FqNameUnsafe
+import org.jetbrains.kotlin.resolve.DescriptorUtils.getFqName
+
+private fun IrType.isBuiltInClassType(descriptorPredicate: (ClassDescriptor) -> Boolean, hasQuestionMark: Boolean): Boolean {
+    if (this !is IrSimpleType) return false
+    if (this.hasQuestionMark != hasQuestionMark) return false
+    val classSymbol = this.classifier as? IrClassSymbol ?: return false
+    return descriptorPredicate(classSymbol.descriptor)
+}
+
+private fun IrType.isNotNullClassType(fqName: FqNameUnsafe) = isClassType(fqName, hasQuestionMark = false)
+private fun IrType.isNullableClassType(fqName: FqNameUnsafe) = isClassType(fqName, hasQuestionMark = true)
+
+private fun IrType.isClassType(fqName: FqNameUnsafe, hasQuestionMark: Boolean): Boolean {
+    if (this !is IrSimpleType) return false
+    if (this.hasQuestionMark != hasQuestionMark) return false
+    val classSymbol = this.classifier as? IrClassSymbol ?: return false
+    return classFqNameEquals(classSymbol.descriptor, fqName)
+}
+
+private fun classFqNameEquals(descriptor: ClassDescriptor, fqName: FqNameUnsafe): Boolean =
+    descriptor.name == fqName.shortName() && fqName == getFqName(descriptor)
+
+fun IrType.isNullableAny(): Boolean = isBuiltInClassType(KotlinBuiltIns::isAny, hasQuestionMark = true)
+
+fun IrType.isString(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES.string)
+fun IrType.isArray(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES.array)
+fun IrType.isNothing(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES.nothing)
+fun IrType.isPrimitiveType(): Boolean =
+    isBuiltInClassType(KotlinBuiltIns::isPrimitiveClass, hasQuestionMark = false)
+
+fun IrType.isNullablePrimitiveType(): Boolean =
+    isBuiltInClassType(KotlinBuiltIns::isPrimitiveClass, hasQuestionMark = true)
+
+fun IrType.isUnit() = isNotNullClassType(KotlinBuiltIns.FQ_NAMES.unit)
+fun IrType.isNullableUnit() = isNullableClassType(KotlinBuiltIns.FQ_NAMES.unit)
+fun IrType.isUnitOrNullableUnit() = this.isUnit() || this.isNullableUnit()
+
+fun IrType.isBoolean(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._boolean)
+fun IrType.isChar(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._char)
+fun IrType.isByte(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._byte)
+fun IrType.isShort(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._short)
+fun IrType.isInt(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._int)
+fun IrType.isLong(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._long)
+fun IrType.isFloat(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._float)
+fun IrType.isDouble(): Boolean = isNotNullClassType(KotlinBuiltIns.FQ_NAMES._double)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypes.kt

@@ -5,10 +5,11 @@
 
 package org.jetbrains.kotlin.ir.types
 
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.ir.symbols.IrClassifierSymbol
 import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
 import org.jetbrains.kotlin.ir.types.impl.originalKotlinType
-import org.jetbrains.kotlin.types.Variance
+import org.jetbrains.kotlin.types.*
 import org.jetbrains.kotlin.utils.addToStdlib.cast
 import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 
@@ -52,4 +53,20 @@ fun IrType.makeNullable() =
             Variance.INVARIANT
         )
     else
-        this
+        this
+
+fun IrType.toKotlinType(): KotlinType = when (this) {
+    is IrSimpleType -> {
+        val classifier = this.classifier.descriptor
+        val arguments = this.arguments.mapIndexed { index, it ->
+            when (it) {
+                is IrTypeProjection -> TypeProjectionImpl(it.variance, it.type.toKotlinType())
+                is IrStarProjection -> StarProjectionImpl((classifier as ClassDescriptor).declaredTypeParameters[index])
+                else -> error(it)
+            }
+        }
+
+        classifier.defaultType.replace(newArguments = arguments).makeNullableAsSpecified(this.hasQuestionMark)
+    }
+    else -> TODO(this.toString())
+}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/IrUtils.kt

@@ -18,6 +18,7 @@ import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.symbols.IrValueParameterSymbol
+import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.psi.psiUtil.endOffset
 import org.jetbrains.kotlin.psi.psiUtil.startOffset
@@ -79,6 +80,36 @@ fun IrFunctionAccessExpression.getArgumentsWithSymbols(): List<Pair<IrValueParam
     return res
 }
 
+/**
+ * Binds the arguments explicitly represented in the IR to the parameters of the accessed function.
+ * The arguments are to be evaluated in the same order as they appear in the resulting list.
+ */
+fun IrMemberAccessExpression.getArgumentsWithIr(): List<Pair<IrValueParameter, IrExpression>> {
+    val res = mutableListOf<Pair<IrValueParameter, IrExpression>>()
+    val irFunction = when (this) {
+        is IrFunctionAccessExpression -> this.symbol.owner
+        is IrFunctionReference -> this.symbol.owner
+        else -> error(this)
+    }
+
+    dispatchReceiver?.let {
+        res += (irFunction.dispatchReceiverParameter!! to it)
+    }
+
+    extensionReceiver?.let {
+        res += (irFunction.extensionReceiverParameter!! to it)
+    }
+
+    irFunction.valueParameters.forEachIndexed { index, it ->
+        val arg = getValueArgument(index)
+        if (arg != null) {
+            res += (it to arg)
+        }
+    }
+
+    return res
+}
+
 /**
  * Sets arguments that are specified by given mapping of parameters.
  */
@@ -203,14 +234,20 @@ val DeclarationDescriptorWithSource.endOffsetOrUndefined: Int get() = endOffset
 val IrClassSymbol.functions: Sequence<IrSimpleFunctionSymbol>
     get() = this.owner.declarations.asSequence().filterIsInstance<IrSimpleFunction>().map { it.symbol }
 
+val IrClass.functions: Sequence<IrSimpleFunction>
+    get() = this.declarations.asSequence().filterIsInstance<IrSimpleFunction>()
+
 val IrClassSymbol.constructors: Sequence<IrConstructorSymbol>
     get() = this.owner.declarations.asSequence().filterIsInstance<IrConstructor>().map { it.symbol }
 
-val IrFunction.explicitParameters: List<IrValueParameterSymbol>
-    get() = (listOfNotNull(dispatchReceiverParameter, extensionReceiverParameter) + valueParameters).map { it.symbol }
+val IrClass.constructors: Sequence<IrConstructor>
+    get() = this.declarations.asSequence().filterIsInstance<IrConstructor>()
 
-val IrClass.defaultType: KotlinType
-    get() = this.descriptor.defaultType
+val IrFunction.explicitParameters: List<IrValueParameter>
+    get() = (listOfNotNull(dispatchReceiverParameter, extensionReceiverParameter) + valueParameters)
+
+val IrClass.defaultType: IrType
+    get() = this.thisReceiver!!.type
 
 val IrSimpleFunction.isReal: Boolean get() = descriptor.kind.isReal
 
@@ -263,3 +300,31 @@ fun IrAnnotationContainer.hasAnnotation(name: FqName) =
     annotations.any {
         it.symbol.owner.parentAsClass.descriptor.fqNameSafe == name
     }
+
+fun IrValueParameter.copy(newDescriptor: ParameterDescriptor): IrValueParameter {
+    assert(this.descriptor.type == newDescriptor.type)
+
+    return IrValueParameterImpl(
+        startOffset,
+        endOffset,
+        IrDeclarationOrigin.DEFINED,
+        newDescriptor,
+        type,
+        varargElementType
+    )
+}
+
+fun IrFunction.createDispatchReceiverParameter() {
+    assert(this.dispatchReceiverParameter == null)
+
+    val descriptor = this.descriptor.dispatchReceiverParameter ?: return
+
+    this.dispatchReceiverParameter = IrValueParameterImpl(
+        startOffset,
+        endOffset,
+        IrDeclarationOrigin.DEFINED,
+        descriptor,
+        this.parentAsClass.defaultType,
+        null
+    ).also { it.parent = this }
+}