IR: do not use Ir*Impl elements where it's not necessary

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

@@ -122,7 +122,7 @@ inline fun IrProperty.addSetter(builder: IrFunctionBuilder.() -> Unit = {}): IrS
         }
     }
 
-fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null): IrFunctionImpl {
+fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null): IrSimpleFunction {
     val wrappedDescriptor = when (originalDescriptor) {
         is DescriptorWithContainerSource -> WrappedFunctionDescriptorWithContainerSource(originalDescriptor.containerSource)
         is PropertyGetterDescriptor -> WrappedPropertyGetterDescriptor(originalDescriptor.annotations, originalDescriptor.source)
@@ -141,7 +141,7 @@ fun IrFunctionBuilder.buildFun(originalDescriptor: FunctionDescriptor? = null):
     }
 }
 
-fun IrFunctionBuilder.buildConstructor(): IrConstructorImpl {
+fun IrFunctionBuilder.buildConstructor(): IrConstructor {
     val wrappedDescriptor = WrappedClassConstructorDescriptor()
     return IrConstructorImpl(
         startOffset, endOffset, origin,
@@ -159,19 +159,21 @@ fun IrFunctionBuilder.buildConstructor(): IrConstructorImpl {
  * potentially external function (e.g. in an IrCall) we have to ensure that we keep
  * information from the original descriptor so as not to break inlining.
  */
-inline fun buildFunWithDescriptorForInlining(originalDescriptor: FunctionDescriptor, builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
+inline fun buildFunWithDescriptorForInlining(
+    originalDescriptor: FunctionDescriptor, builder: IrFunctionBuilder.() -> Unit
+): IrSimpleFunction =
     IrFunctionBuilder().run {
         builder()
         buildFun(originalDescriptor)
     }
 
-inline fun buildFun(builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
+inline fun buildFun(builder: IrFunctionBuilder.() -> Unit): IrSimpleFunction =
     IrFunctionBuilder().run {
         builder()
         buildFun()
     }
 
-inline fun IrDeclarationContainer.addFunction(builder: IrFunctionBuilder.() -> Unit): IrFunctionImpl =
+inline fun IrDeclarationContainer.addFunction(builder: IrFunctionBuilder.() -> Unit): IrSimpleFunction =
     buildFun(builder).also { function ->
         declarations.add(function)
         function.parent = this@addFunction
@@ -201,13 +203,13 @@ fun IrDeclarationContainer.addFunction(
         }
     }
 
-inline fun buildConstructor(builder: IrFunctionBuilder.() -> Unit): IrConstructorImpl =
+inline fun buildConstructor(builder: IrFunctionBuilder.() -> Unit): IrConstructor =
     IrFunctionBuilder().run {
         builder()
         buildConstructor()
     }
 
-inline fun IrClass.addConstructor(builder: IrFunctionBuilder.() -> Unit = {}): IrConstructorImpl =
+inline fun IrClass.addConstructor(builder: IrFunctionBuilder.() -> Unit = {}): IrConstructor =
     buildConstructor {
         builder()
         returnType = defaultType

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/CreateScriptFunctionsPhase.kt

@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.ir.backend.js.lower
 
 import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
-import org.jetbrains.kotlin.backend.common.phaser.makeIrModulePhase
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.IrStatement
@@ -89,7 +88,7 @@ class CreateScriptFunctionsPhase(val context: CommonBackendContext) : FileLoweri
         return (irScript.statements.lastOrNull() as? IrExpression)?.type ?: context.irBuiltIns.unitType
     }
 
-    private fun createFunction(irScript: IrScript, name: String, returnType: IrType): IrFunctionImpl {
+    private fun createFunction(irScript: IrScript, name: String, returnType: IrType): IrSimpleFunction {
         val (startOffset, endOffset) = getFunctionBodyOffsets(irScript)
         val descriptor = WrappedSimpleFunctionDescriptor()
 

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

@@ -31,7 +31,6 @@ import org.jetbrains.kotlin.ir.builders.IrBuilderWithScope
 import org.jetbrains.kotlin.ir.builders.irBlock
 import org.jetbrains.kotlin.ir.builders.irNull
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrFunctionReference
@@ -101,7 +100,7 @@ class JvmBackendContext(
     internal val multifileFacadeClassForPart = mutableMapOf<IrClass, IrClass>()
     internal val multifileFacadeMemberToPartMember = mutableMapOf<IrFunction, IrFunction>()
 
-    internal val hiddenConstructors = mutableMapOf<IrConstructor, IrConstructorImpl>()
+    internal val hiddenConstructors = mutableMapOf<IrConstructor, IrConstructor>()
 
     internal val collectionStubComputer = CollectionStubComputer(this)
 

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

@@ -24,7 +24,6 @@ import org.jetbrains.kotlin.ir.builders.declarations.addField
 import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
 import org.jetbrains.kotlin.ir.builders.declarations.buildConstructor
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrExpressionBodyImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
@@ -53,7 +52,7 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP
     }
 
     private inner class EnumClassTransformer(val irClass: IrClass) {
-        private val loweredEnumConstructors = hashMapOf<IrConstructorSymbol, IrConstructorImpl>()
+        private val loweredEnumConstructors = hashMapOf<IrConstructorSymbol, IrConstructor>()
         private val loweredEnumConstructorParameters = hashMapOf<IrValueParameterSymbol, IrValueParameter>()
         private val enumEntryOrdinals = TObjectIntHashMap<IrEnumEntry>()
         private val declarationToEnumEntry = mutableMapOf<IrDeclaration, IrEnumEntry>()

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

@@ -15,13 +15,11 @@ import org.jetbrains.kotlin.backend.jvm.ir.needsAccessor
 import org.jetbrains.kotlin.config.LanguageFeature
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.Modality
-import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrFieldAccessExpression
@@ -29,7 +27,10 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrBlockBodyImpl
 import org.jetbrains.kotlin.ir.types.classifierOrFail
 import org.jetbrains.kotlin.ir.types.makeNotNull
 import org.jetbrains.kotlin.ir.types.typeWith
-import org.jetbrains.kotlin.ir.util.*
+import org.jetbrains.kotlin.ir.util.coerceToUnit
+import org.jetbrains.kotlin.ir.util.render
+import org.jetbrains.kotlin.ir.util.resolveFakeOverride
+import org.jetbrains.kotlin.ir.util.transformDeclarationsFlat
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.name.Name
@@ -119,7 +120,7 @@ class JvmPropertiesLowering(private val backendContext: JvmBackendContext) : IrE
     private fun shouldSubstituteAccessorWithField(property: IrProperty, accessor: IrSimpleFunction?): Boolean =
         accessor != null && !property.needsAccessor(accessor)
 
-    private fun createSyntheticMethodForAnnotations(declaration: IrProperty): IrFunctionImpl =
+    private fun createSyntheticMethodForAnnotations(declaration: IrProperty): IrSimpleFunction =
         buildFun {
             origin = JvmLoweredDeclarationOrigin.SYNTHETIC_METHOD_FOR_PROPERTY_ANNOTATIONS
             name = Name.identifier(computeSyntheticMethodName(declaration))

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

@@ -26,7 +26,6 @@ import org.jetbrains.kotlin.ir.builders.declarations.addValueParameter
 import org.jetbrains.kotlin.ir.builders.declarations.buildConstructor
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrConstructorImpl
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.*
 import org.jetbrains.kotlin.ir.symbols.*
@@ -219,7 +218,7 @@ internal class SyntheticAccessorLowering(val context: JvmBackendContext) : IrEle
                         origin != JvmLoweredDeclarationOrigin.SYNTHETIC_ACCESSOR &&
                         origin != JvmLoweredDeclarationOrigin.SYNTHETIC_ACCESSOR_FOR_HIDDEN_CONSTRUCTOR)
 
-    private fun handleHiddenConstructor(declaration: IrConstructor): IrConstructorImpl {
+    private fun handleHiddenConstructor(declaration: IrConstructor): IrConstructor {
         require(declaration.isOrShouldBeHidden, declaration::render)
         return context.hiddenConstructors.getOrPut(declaration) {
             declaration.makeConstructorAccessor(JvmLoweredDeclarationOrigin.SYNTHETIC_ACCESSOR_FOR_HIDDEN_CONSTRUCTOR).also { accessor ->
@@ -254,7 +253,7 @@ internal class SyntheticAccessorLowering(val context: JvmBackendContext) : IrEle
     private fun IrConstructor.makeConstructorAccessor(
         originForConstructorAccessor: IrDeclarationOrigin =
             JvmLoweredDeclarationOrigin.SYNTHETIC_ACCESSOR
-    ): IrConstructorImpl {
+    ): IrConstructor {
         val source = this
 
         return buildConstructor {

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

@@ -19,7 +19,6 @@ import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.builders.declarations.buildFunWithDescriptorForInlining
 import org.jetbrains.kotlin.ir.builders.declarations.buildProperty
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
@@ -184,7 +183,7 @@ class MemoizedInlineClassReplacements(private val mangleReturnTypes: Boolean) {
         function: IrFunction,
         replacementOrigin: IrDeclarationOrigin,
         noFakeOverride: Boolean = false,
-        body: IrFunctionImpl.() -> Unit
+        body: IrFunction.() -> Unit
     ) = buildFunWithDescriptorForInlining(function.descriptor) {
         updateFrom(function)
         if (function is IrConstructor) {

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/IrInterpreter.kt

@@ -5,6 +5,13 @@
 
 package org.jetbrains.kotlin.ir.interpreter
 
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.impl.IrConstructorCallImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrErrorExpressionImpl
 import org.jetbrains.kotlin.ir.interpreter.builtins.*
 import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterException
 import org.jetbrains.kotlin.ir.interpreter.exceptions.InterpreterMethodNotFoundException
@@ -13,15 +20,6 @@ import org.jetbrains.kotlin.ir.interpreter.intrinsics.IntrinsicEvaluator
 import org.jetbrains.kotlin.ir.interpreter.stack.StackImpl
 import org.jetbrains.kotlin.ir.interpreter.stack.Variable
 import org.jetbrains.kotlin.ir.interpreter.state.*
-import org.jetbrains.kotlin.ir.IrElement
-import org.jetbrains.kotlin.ir.IrStatement
-import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
-import org.jetbrains.kotlin.ir.declarations.lazy.IrLazyFunction
-import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
-import org.jetbrains.kotlin.ir.expressions.*
-import org.jetbrains.kotlin.ir.expressions.impl.IrConstructorCallImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrErrorExpressionImpl
 import org.jetbrains.kotlin.ir.symbols.IrSymbol
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.types.impl.originalKotlinType
@@ -100,8 +98,7 @@ class IrInterpreter(private val irBuiltIns: IrBuiltIns, private val bodyMap: Map
         try {
             incrementAndCheckCommands()
             val executionResult = when (this) {
-                is IrFunctionImpl -> interpretFunction(this)
+                is IrSimpleFunction -> interpretFunction(this)
-                is IrLazyFunction -> interpretFunction(this as IrSimpleFunction)
                 is IrCall -> interpretCall(this)
                 is IrConstructorCall -> interpretConstructorCall(this)
                 is IrEnumConstructorCall -> interpretEnumConstructorCall(this)

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/Label.kt

@@ -9,6 +9,7 @@ import org.jetbrains.kotlin.ir.interpreter.stack.Stack
 import org.jetbrains.kotlin.ir.interpreter.state.Primitive
 import org.jetbrains.kotlin.ir.interpreter.state.isSubtypeOf
 import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.declarations.lazy.IrLazyFunction
 import org.jetbrains.kotlin.ir.expressions.IrCall
@@ -30,7 +31,7 @@ open class ExecutionResult(val returnLabel: ReturnLabel, private val owner: IrEl
     fun getNextLabel(irElement: IrElement, interpret: IrElement.() -> ExecutionResult): ExecutionResult {
         return when (returnLabel) {
             ReturnLabel.RETURN -> when (irElement) {
-                is IrCall, is IrReturnableBlock, is IrFunctionImpl, is IrLazyFunction -> if (owner == irElement) Next else this
+                is IrCall, is IrReturnableBlock, is IrSimpleFunction -> if (owner == irElement) Next else this
                 else -> this
             }
             ReturnLabel.BREAK_WHEN -> when (irElement) {

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/state/Wrapper.kt

@@ -5,18 +5,18 @@
 
 package org.jetbrains.kotlin.ir.interpreter.state
 
-import org.jetbrains.kotlin.ir.interpreter.builtins.evaluateIntrinsicAnnotation
-import org.jetbrains.kotlin.ir.interpreter.*
-import org.jetbrains.kotlin.ir.interpreter.getEvaluateIntrinsicValue
-import org.jetbrains.kotlin.ir.interpreter.getPrimitiveClass
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.declarations.IrFunction
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
+import org.jetbrains.kotlin.ir.interpreter.*
+import org.jetbrains.kotlin.ir.interpreter.builtins.evaluateIntrinsicAnnotation
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.types.*
-import org.jetbrains.kotlin.ir.util.*
+import org.jetbrains.kotlin.ir.util.defaultType
+import org.jetbrains.kotlin.ir.util.fqNameForIrSerialization
+import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
+import org.jetbrains.kotlin.ir.util.parentAsClass
 import java.lang.invoke.MethodHandle
 import java.lang.invoke.MethodHandles
 import java.lang.invoke.MethodType
@@ -144,7 +144,7 @@ internal class Wrapper(val value: Any, override val irClass: IrClass) : Complex(
 
         private fun IrFunction.getOriginalOverriddenSymbols(): MutableList<IrFunctionSymbol> {
             val overriddenSymbols = mutableListOf<IrFunctionSymbol>()
-            if (this is IrFunctionImpl) {
+            if (this is IrSimpleFunction) {
                 val pool = this.overriddenSymbols.toMutableList()
                 val iterator = pool.listIterator()
                 for (symbol in iterator) {

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/impl/IrExternalPackageFragmentImpl.kt

@@ -19,8 +19,8 @@ package org.jetbrains.kotlin.ir.declarations.impl
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
 import org.jetbrains.kotlin.descriptors.impl.EmptyPackageFragmentDescriptor
-import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.IrElementBase
+import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrExternalPackageFragment
@@ -29,6 +29,7 @@ import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedContainerSource
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedMemberDescriptor
 
 class IrExternalPackageFragmentImpl(
@@ -42,12 +43,14 @@ class IrExternalPackageFragmentImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val packageFragmentDescriptor: PackageFragmentDescriptor get() = symbol.descriptor
+    override val packageFragmentDescriptor: PackageFragmentDescriptor
+        get() = symbol.descriptor
 
     override val declarations: MutableList<IrDeclaration> = ArrayList()
 
     @OptIn(ObsoleteDescriptorBasedAPI::class)
-    override val containerSource get() = (symbol.descriptor as? DeserializedMemberDescriptor)?.containerSource
+    override val containerSource: DeserializedContainerSource?
+        get() = (symbol.descriptor as? DeserializedMemberDescriptor)?.containerSource
 
     override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
         visitor.visitExternalPackageFragment(this, data)
@@ -63,12 +66,9 @@ class IrExternalPackageFragmentImpl(
     }
 
     companion object {
-        fun createEmptyExternalPackageFragment(
+        fun createEmptyExternalPackageFragment(module: ModuleDescriptor, fqName: FqName): IrExternalPackageFragment =
-            module: ModuleDescriptor,
-            fqName: FqName
-        ): IrExternalPackageFragmentImpl =
             IrExternalPackageFragmentImpl(
                 IrExternalPackageFragmentSymbolImpl(EmptyPackageFragmentDescriptor(module, fqName)), fqName
             )
     }
-}
+}

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

@@ -6,9 +6,9 @@
 package org.jetbrains.kotlin.ir.util
 
 import org.jetbrains.kotlin.descriptors.ScriptDescriptor
-import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.*
 import org.jetbrains.kotlin.ir.expressions.*
@@ -307,7 +307,7 @@ open class DeepCopyIrTreeWithSymbols(
             declaration.superTypes.mapTo(superTypes) { it.remapType() }
         }
 
-    private fun copyTypeParameter(declaration: IrTypeParameter) =
+    private fun copyTypeParameter(declaration: IrTypeParameter): IrTypeParameter =
         IrTypeParameterImpl(
             declaration.startOffset, declaration.endOffset,
             mapDeclarationOrigin(declaration.origin),

compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileDeserializer.kt

@@ -997,7 +997,7 @@ abstract class IrFileDeserializer(
         return result
     }
 
-    private fun deserializeIrValueParameter(proto: ProtoValueParameter, index: Int) =
+    private fun deserializeIrValueParameter(proto: ProtoValueParameter, index: Int): IrValueParameter =
         withDeserializedIrDeclarationBase(proto.base) { symbol, _, startOffset, endOffset, origin, fcode ->
             val flags = ValueParameterFlags.decode(fcode)
             val nameAndType = BinaryNameAndType.decode(proto.nameType)
@@ -1019,7 +1019,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrClass(proto: ProtoClass) =
+    private fun deserializeIrClass(proto: ProtoClass): IrClass =
         withDeserializedIrDeclarationBase(proto.base) { symbol, signature, startOffset, endOffset, origin, fcode ->
             val flags = ClassFlags.decode(fcode)
 
@@ -1054,7 +1054,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrTypeAlias(proto: ProtoTypeAlias) =
+    private fun deserializeIrTypeAlias(proto: ProtoTypeAlias): IrTypeAlias =
         withDeserializedIrDeclarationBase(proto.base) { symbol, uniqId, startOffset, endOffset, origin, fcode ->
             symbolTable.declareTypeAliasFromLinker((symbol as IrTypeAliasSymbol).descriptor, uniqId) {
                 val flags = TypeAliasFlags.decode(fcode)
@@ -1113,7 +1113,7 @@ abstract class IrFileDeserializer(
     private inline fun <T : IrFunction> withDeserializedIrFunctionBase(
         proto: ProtoFunctionBase,
         block: (IrFunctionSymbol, IdSignature, Int, Int, IrDeclarationOrigin, Long) -> T
-    ) = withDeserializedIrDeclarationBase(proto.base) { symbol, idSig, startOffset, endOffset, origin, fcode ->
+    ): T = withDeserializedIrDeclarationBase(proto.base) { symbol, idSig, startOffset, endOffset, origin, fcode ->
         symbolTable.withScope(symbol.descriptor) {
             block(symbol as IrFunctionSymbol, idSig, startOffset, endOffset, origin, fcode).usingParent {
                 withInlineGuard {
@@ -1163,7 +1163,7 @@ abstract class IrFileDeserializer(
         }
     }
 
-    private fun deserializeIrVariable(proto: ProtoVariable) =
+    private fun deserializeIrVariable(proto: ProtoVariable): IrVariable =
         withDeserializedIrDeclarationBase(proto.base) { symbol, _, startOffset, endOffset, origin, fcode ->
             val flags = LocalVariableFlags.decode(fcode)
             val nameType = BinaryNameAndType.decode(proto.nameType)
@@ -1197,7 +1197,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrAnonymousInit(proto: ProtoAnonymousInit) =
+    private fun deserializeIrAnonymousInit(proto: ProtoAnonymousInit): IrAnonymousInitializer =
         withDeserializedIrDeclarationBase(proto.base) { symbol, _, startOffset, endOffset, origin, _ ->
             IrAnonymousInitializerImpl(startOffset, endOffset, origin, symbol as IrAnonymousInitializerSymbol).apply {
 //                body = deserializeBlockBody(proto.body.blockBody, startOffset, endOffset)
@@ -1207,7 +1207,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrConstructor(proto: ProtoConstructor) =
+    private fun deserializeIrConstructor(proto: ProtoConstructor): IrConstructor =
         withDeserializedIrFunctionBase(proto.base) { symbol, idSig, startOffset, endOffset, origin, fcode ->
             val flags = FunctionFlags.decode(fcode)
             val nameType = BinaryNameAndType.decode(proto.base.nameType)
@@ -1228,7 +1228,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrField(proto: ProtoField) =
+    private fun deserializeIrField(proto: ProtoField): IrField =
         withDeserializedIrDeclarationBase(proto.base) { symbol, uniqId, startOffset, endOffset, origin, fcode ->
             val nameType = BinaryNameAndType.decode(proto.nameType)
             val type = deserializeIrType(nameType.typeIndex)
@@ -1252,7 +1252,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrLocalDelegatedProperty(proto: ProtoLocalDelegatedProperty) =
+    private fun deserializeIrLocalDelegatedProperty(proto: ProtoLocalDelegatedProperty): IrLocalDelegatedProperty =
         withDeserializedIrDeclarationBase(proto.base) { symbol, _, startOffset, endOffset, origin, fcode ->
             val flags = LocalVariableFlags.decode(fcode)
             val nameAndType = BinaryNameAndType.decode(proto.nameType)
@@ -1272,7 +1272,7 @@ abstract class IrFileDeserializer(
             }
         }
 
-    private fun deserializeIrProperty(proto: ProtoProperty) =
+    private fun deserializeIrProperty(proto: ProtoProperty): IrProperty =
         withDeserializedIrDeclarationBase(proto.base) { symbol, uniqId, startOffset, endOffset, origin, fcode ->
             val flags = PropertyFlags.decode(fcode)
             symbolTable.declarePropertyFromLinker((symbol as IrPropertySymbol).descriptor, uniqId) {
@@ -1391,8 +1391,8 @@ abstract class IrFileDeserializer(
         }
     }
 
-    fun deserializeDeclaration(proto: ProtoDeclaration, parent: IrDeclarationParent) =
+    fun deserializeDeclaration(proto: ProtoDeclaration, parent: IrDeclarationParent): IrDeclaration =
         usingParent(parent) {
             deserializeDeclaration(proto)
         }
-}
+}

plugins/android-extensions/android-extensions-compiler/src/org/jetbrains/kotlin/android/synthetic/codegen/AndroidIrExtension.kt

@@ -18,14 +18,13 @@ import org.jetbrains.kotlin.backend.common.ir.createImplicitParameterDeclaration
 import org.jetbrains.kotlin.backend.common.lower.DeclarationIrBuilder
 import org.jetbrains.kotlin.backend.common.lower.irBlock
 import org.jetbrains.kotlin.descriptors.*
-import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.builders.declarations.*
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrTypeOperator
@@ -75,7 +74,7 @@ private class AndroidIrTransformer(val extension: AndroidIrExtension, val plugin
             }
         }
 
-    private fun createMethod(fqName: FqName, type: IrType, inInterface: Boolean = false, f: IrFunctionImpl.() -> Unit = {}) =
+    private fun createMethod(fqName: FqName, type: IrType, inInterface: Boolean = false, f: IrFunction.() -> Unit = {}) =
         cachedMethods.getOrPut(fqName) {
             val parent = createClass(fqName.parent(), inInterface)
             parent.addFunction {

plugins/kotlin-serialization/kotlin-serialization-compiler/src/org/jetbrains/kotlinx/serialization/compiler/backend/ir/GeneratorHelpers.kt

@@ -381,7 +381,7 @@ interface IrBuilderExtension {
         copyTypeParameters: Boolean = true
     ) {
         val function = this
-        fun irValueParameter(descriptor: ParameterDescriptor): IrValueParameterImpl = with(descriptor) {
+        fun irValueParameter(descriptor: ParameterDescriptor): IrValueParameter = with(descriptor) {
             IrValueParameterImpl(
                 function.startOffset, function.endOffset, SERIALIZABLE_PLUGIN_ORIGIN, IrValueParameterSymbolImpl(this),
                 name, indexOrMinusOne, type.toIrType(), varargElementType?.toIrType(), isCrossinline, isNoinline