diff --git a/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaClass.kt b/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaClass.kt
index 388cc00589c..b6160395420 100644
--- a/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaClass.kt
+++ b/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaClass.kt
@@ -17,7 +17,6 @@ import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.builder.AbstractFirRegularClassBuilder
 import org.jetbrains.kotlin.fir.declarations.impl.FirDeclarationStatusImpl
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableClass
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.java.JavaTypeParameterStack
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
@@ -46,7 +45,7 @@ class FirJavaClass @FirImplementationDetail internal constructor(
     override val typeParameters: MutableList<FirTypeParameter>,
     internal val javaTypeParameterStack: JavaTypeParameterStack,
     internal val existingNestedClassifierNames: List<Name>
-) : FirPureAbstractElement(), FirRegularClass, FirModifiableClass<FirRegularClass> {
+) : FirRegularClass() {
     override val hasLazyNestedClassifiers: Boolean get() = true
 
     init {
diff --git a/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaConstructor.kt b/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaConstructor.kt
index 762228f546e..521509dfe33 100644
--- a/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaConstructor.kt
+++ b/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaConstructor.kt
@@ -38,7 +38,7 @@ class FirJavaConstructor @FirImplementationDetail constructor(
     override val annotations: MutableList<FirAnnotationCall>,
     override var status: FirDeclarationStatus,
     override var resolvePhase: FirResolvePhase,
-) : FirPureAbstractElement(), FirConstructor {
+) : FirConstructor() {
     override val receiverTypeRef: FirTypeRef? get() = null
 
     init {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/builder/FirAbstractAnnotatedElementBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/builder/FirAbstractAnnotatedElementBuilder.kt
deleted file mode 100644
index 969876dbe9b..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/builder/FirAbstractAnnotatedElementBuilder.kt
+++ /dev/null
@@ -1,42 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.builder
-
-import kotlin.contracts.*
-import org.jetbrains.kotlin.fir.FirAnnotationContainer
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-@FirBuilderDsl
-class FirAbstractAnnotatedElementBuilder {
-    var source: FirSourceElement? = null
-    val annotations: MutableList<FirAnnotationCall> = mutableListOf()
-
-    fun build(): FirAnnotationContainer {
-        return FirAbstractAnnotatedElement(
-            source,
-            annotations,
-        )
-    }
-
-}
-
-@UseExperimental(ExperimentalContracts::class)
-inline fun buildAbstractAnnotatedElement(init: FirAbstractAnnotatedElementBuilder.() -> Unit = {}): FirAnnotationContainer {
-    contract {
-        callsInPlace(init, kotlin.contracts.InvocationKind.EXACTLY_ONCE)
-    }
-    return FirAbstractAnnotatedElementBuilder().apply(init).build()
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousFunction.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousFunction.kt
index 82648ced8ea..5e84e7d9722 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousFunction.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousFunction.kt
@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.fir.declarations
 
 import org.jetbrains.kotlin.contracts.description.InvocationKind
 import org.jetbrains.kotlin.fir.FirLabel
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -23,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirAnonymousFunction : FirPureAbstractElement(), FirFunction<FirAnonymousFunction>, FirExpression {
+abstract class FirAnonymousFunction : FirFunction<FirAnonymousFunction>, FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousObject.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousObject.kt
index 2c0cc444192..7db8d7f62fb 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousObject.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirAnonymousObject.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.declarations
 
 import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -21,7 +20,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirAnonymousObject : FirPureAbstractElement(), FirClass<FirAnonymousObject>, FirExpression {
+abstract class FirAnonymousObject : FirClass<FirAnonymousObject>, FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirConstructor.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirConstructor.kt
index 531315baaea..b2807e95478 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirConstructor.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirConstructor.kt
@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -21,32 +22,32 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirConstructor : FirFunction<FirConstructor>, FirCallableMemberDeclaration<FirConstructor> {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override val resolvePhase: FirResolvePhase
-    override val returnTypeRef: FirTypeRef
-    override val receiverTypeRef: FirTypeRef?
-    override val typeParameters: List<FirTypeParameter>
-    override val controlFlowGraphReference: FirControlFlowGraphReference
-    override val valueParameters: List<FirValueParameter>
-    override val status: FirDeclarationStatus
-    override val containerSource: DeserializedContainerSource?
-    override val annotations: List<FirAnnotationCall>
-    override val symbol: FirConstructorSymbol
-    val delegatedConstructor: FirDelegatedConstructorCall?
-    override val body: FirBlock?
-    val isPrimary: Boolean
+abstract class FirConstructor : FirPureAbstractElement(), FirFunction<FirConstructor>, FirCallableMemberDeclaration<FirConstructor> {
+    abstract override val source: FirSourceElement?
+    abstract override val session: FirSession
+    abstract override val resolvePhase: FirResolvePhase
+    abstract override val returnTypeRef: FirTypeRef
+    abstract override val receiverTypeRef: FirTypeRef?
+    abstract override val typeParameters: List<FirTypeParameter>
+    abstract override val controlFlowGraphReference: FirControlFlowGraphReference
+    abstract override val valueParameters: List<FirValueParameter>
+    abstract override val status: FirDeclarationStatus
+    abstract override val containerSource: DeserializedContainerSource?
+    abstract override val annotations: List<FirAnnotationCall>
+    abstract override val symbol: FirConstructorSymbol
+    abstract val delegatedConstructor: FirDelegatedConstructorCall?
+    abstract override val body: FirBlock?
+    abstract val isPrimary: Boolean
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitConstructor(this, data)
 
-    override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirConstructor
+    abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirConstructor
 
-    override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirConstructor
+    abstract override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirConstructor
 
-    override fun <D> transformControlFlowGraphReference(transformer: FirTransformer<D>, data: D): FirConstructor
+    abstract override fun <D> transformControlFlowGraphReference(transformer: FirTransformer<D>, data: D): FirConstructor
 
-    override fun <D> transformValueParameters(transformer: FirTransformer<D>, data: D): FirConstructor
+    abstract override fun <D> transformValueParameters(transformer: FirTransformer<D>, data: D): FirConstructor
 
-    override fun <D> transformStatus(transformer: FirTransformer<D>, data: D): FirConstructor
+    abstract override fun <D> transformStatus(transformer: FirTransformer<D>, data: D): FirConstructor
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirEnumEntry.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirEnumEntry.kt
index fb6ad0b331c..a6e55ae3052 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirEnumEntry.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirEnumEntry.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -22,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirEnumEntry : FirPureAbstractElement(), FirVariable<FirEnumEntry>, FirCallableMemberDeclaration<FirEnumEntry> {
+abstract class FirEnumEntry : FirVariable<FirEnumEntry>(), FirCallableMemberDeclaration<FirEnumEntry> {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirField.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirField.kt
index 014dad06fa4..32adabc4104 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirField.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirField.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -22,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirField : FirPureAbstractElement(), FirVariable<FirField>, FirCallableMemberDeclaration<FirField> {
+abstract class FirField : FirVariable<FirField>(), FirCallableMemberDeclaration<FirField> {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirProperty.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirProperty.kt
index 3cb744aeee8..88ac26edc4b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirProperty.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirProperty.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -24,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirProperty : FirPureAbstractElement(), FirVariable<FirProperty>, FirTypeParametersOwner, FirCallableMemberDeclaration<FirProperty> {
+abstract class FirProperty : FirVariable<FirProperty>(), FirTypeParametersOwner, FirCallableMemberDeclaration<FirProperty> {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirRegularClass.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirRegularClass.kt
index a100723a0f1..ee23285fb3f 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirRegularClass.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirRegularClass.kt
@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations
 
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -20,25 +21,25 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirRegularClass : FirMemberDeclaration, FirTypeParametersOwner, FirClass<FirRegularClass> {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override val resolvePhase: FirResolvePhase
-    override val annotations: List<FirAnnotationCall>
-    override val typeParameters: List<FirTypeParameter>
-    override val status: FirDeclarationStatus
-    override val classKind: ClassKind
-    override val declarations: List<FirDeclaration>
-    override val scopeProvider: FirScopeProvider
-    val name: Name
-    override val symbol: FirRegularClassSymbol
-    val companionObject: FirRegularClass?
-    val hasLazyNestedClassifiers: Boolean
-    override val superTypeRefs: List<FirTypeRef>
+abstract class FirRegularClass : FirPureAbstractElement(), FirMemberDeclaration, FirTypeParametersOwner, FirClass<FirRegularClass> {
+    abstract override val source: FirSourceElement?
+    abstract override val session: FirSession
+    abstract override val resolvePhase: FirResolvePhase
+    abstract override val annotations: List<FirAnnotationCall>
+    abstract override val typeParameters: List<FirTypeParameter>
+    abstract override val status: FirDeclarationStatus
+    abstract override val classKind: ClassKind
+    abstract override val declarations: List<FirDeclaration>
+    abstract override val scopeProvider: FirScopeProvider
+    abstract val name: Name
+    abstract override val symbol: FirRegularClassSymbol
+    abstract val companionObject: FirRegularClass?
+    abstract val hasLazyNestedClassifiers: Boolean
+    abstract override val superTypeRefs: List<FirTypeRef>
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitRegularClass(this, data)
 
-    override fun replaceSuperTypeRefs(newSuperTypeRefs: List<FirTypeRef>)
+    abstract override fun replaceSuperTypeRefs(newSuperTypeRefs: List<FirTypeRef>)
 
-    override fun <D> transformStatus(transformer: FirTransformer<D>, data: D): FirRegularClass
+    abstract override fun <D> transformStatus(transformer: FirTransformer<D>, data: D): FirRegularClass
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirSealedClass.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirSealedClass.kt
index 5d6975a84cb..c48f74aa786 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirSealedClass.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirSealedClass.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.declarations
 
 import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -22,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirSealedClass : FirPureAbstractElement(), FirRegularClass {
+abstract class FirSealedClass : FirRegularClass() {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirValueParameter.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirValueParameter.kt
index 8112f984fd5..96f14603dcd 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirValueParameter.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirValueParameter.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -21,7 +20,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirValueParameter : FirPureAbstractElement(), FirVariable<FirValueParameter> {
+abstract class FirValueParameter : FirVariable<FirValueParameter>() {
     abstract override val source: FirSourceElement?
     abstract override val session: FirSession
     abstract override val resolvePhase: FirResolvePhase
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirVariable.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirVariable.kt
index 44eb78b41d7..3eb30bc77fa 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirVariable.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/FirVariable.kt
@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -21,34 +22,34 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirVariable<F : FirVariable<F>> : FirCallableDeclaration<F>, FirDeclaration, FirStatement {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override val resolvePhase: FirResolvePhase
-    override val returnTypeRef: FirTypeRef
-    override val receiverTypeRef: FirTypeRef?
-    val name: Name
-    override val symbol: FirVariableSymbol<F>
-    val initializer: FirExpression?
-    val delegate: FirExpression?
-    val delegateFieldSymbol: FirDelegateFieldSymbol<F>?
-    val isVar: Boolean
-    val isVal: Boolean
-    val getter: FirPropertyAccessor?
-    val setter: FirPropertyAccessor?
-    override val annotations: List<FirAnnotationCall>
+abstract class FirVariable<F : FirVariable<F>> : FirPureAbstractElement(), FirCallableDeclaration<F>, FirDeclaration, FirStatement {
+    abstract override val source: FirSourceElement?
+    abstract override val session: FirSession
+    abstract override val resolvePhase: FirResolvePhase
+    abstract override val returnTypeRef: FirTypeRef
+    abstract override val receiverTypeRef: FirTypeRef?
+    abstract val name: Name
+    abstract override val symbol: FirVariableSymbol<F>
+    abstract val initializer: FirExpression?
+    abstract val delegate: FirExpression?
+    abstract val delegateFieldSymbol: FirDelegateFieldSymbol<F>?
+    abstract val isVar: Boolean
+    abstract val isVal: Boolean
+    abstract val getter: FirPropertyAccessor?
+    abstract val setter: FirPropertyAccessor?
+    abstract override val annotations: List<FirAnnotationCall>
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitVariable(this, data)
 
-    override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirVariable<F>
+    abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirVariable<F>
 
-    override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirVariable<F>
+    abstract override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirVariable<F>
 
-    fun <D> transformInitializer(transformer: FirTransformer<D>, data: D): FirVariable<F>
+    abstract fun <D> transformInitializer(transformer: FirTransformer<D>, data: D): FirVariable<F>
 
-    fun <D> transformGetter(transformer: FirTransformer<D>, data: D): FirVariable<F>
+    abstract fun <D> transformGetter(transformer: FirTransformer<D>, data: D): FirVariable<F>
 
-    fun <D> transformSetter(transformer: FirTransformer<D>, data: D): FirVariable<F>
+    abstract fun <D> transformSetter(transformer: FirTransformer<D>, data: D): FirVariable<F>
 
-    fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirVariable<F>
+    abstract fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirVariable<F>
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousFunctionBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousFunctionBuilder.kt
index 9e2b4148fd6..1ba61d629d8 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousFunctionBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousFunctionBuilder.kt
@@ -18,7 +18,6 @@ import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirFunctionBuilder
 import org.jetbrains.kotlin.fir.declarations.impl.FirAnonymousFunctionImpl
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableFunction
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousObjectBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousObjectBuilder.kt
index e0bce4a7f67..c69ca05da2b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousObjectBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirAnonymousObjectBuilder.kt
@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.fir.declarations.FirDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.builder.FirClassBuilder
 import org.jetbrains.kotlin.fir.declarations.impl.FirAnonymousObjectImpl
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableClass
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirClassImplBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirClassImplBuilder.kt
index 43c29ecb966..02e925affe8 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirClassImplBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirClassImplBuilder.kt
@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.fir.declarations.builder
 
 import kotlin.contracts.*
 import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
@@ -19,7 +18,6 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.builder.AbstractFirRegularClassBuilder
 import org.jetbrains.kotlin.fir.declarations.impl.FirClassImpl
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableRegularClass
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
 import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirConstructorBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirConstructorBuilder.kt
index 8aba5a4db80..871294c679b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirConstructorBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirConstructorBuilder.kt
@@ -17,7 +17,6 @@ import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirAbstractConstructorBuilder
 import org.jetbrains.kotlin.fir.declarations.impl.FirConstructorImpl
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableConstructor
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPrimaryConstructorBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPrimaryConstructorBuilder.kt
index f26505b5ed9..bfcc8ea695d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPrimaryConstructorBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPrimaryConstructorBuilder.kt
@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirAbstractConstructorBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableConstructor
 import org.jetbrains.kotlin.fir.declarations.impl.FirPrimaryConstructor
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyAccessorBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyAccessorBuilder.kt
index 01c47316c5c..c6157a3072f 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyAccessorBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyAccessorBuilder.kt
@@ -20,7 +20,6 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirFunctionBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableFunction
 import org.jetbrains.kotlin.fir.declarations.impl.FirPropertyAccessorImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyBuilder.kt
index 7c81d85704b..6c637ef203d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirPropertyBuilder.kt
@@ -16,8 +16,6 @@ import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirTypeParametersOwnerBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableVariable
 import org.jetbrains.kotlin.fir.declarations.impl.FirPropertyImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSealedClassBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSealedClassBuilder.kt
index 8d7d8ec7a42..6d86b9a3d88 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSealedClassBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSealedClassBuilder.kt
@@ -18,7 +18,6 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirSealedClass
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.builder.AbstractFirRegularClassBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableRegularClass
 import org.jetbrains.kotlin.fir.declarations.impl.FirSealedClassImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSimpleFunctionBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSimpleFunctionBuilder.kt
index 1933edd4a98..8affe2d52dd 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSimpleFunctionBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirSimpleFunctionBuilder.kt
@@ -20,8 +20,6 @@ import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirFunctionBuilder
 import org.jetbrains.kotlin.fir.declarations.builder.FirTypeParametersOwnerBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableFunction
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
 import org.jetbrains.kotlin.fir.declarations.impl.FirSimpleFunctionImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirTypeAliasBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirTypeAliasBuilder.kt
index 3e0380163ea..06853358c68 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirTypeAliasBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirTypeAliasBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeAlias
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.builder.FirTypeParametersOwnerBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
 import org.jetbrains.kotlin.fir.declarations.impl.FirTypeAliasImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.symbols.impl.FirTypeAliasSymbol
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirValueParameterBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirValueParameterBuilder.kt
index c2e22f36ce9..47830c2fca7 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirValueParameterBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/builder/FirValueParameterBuilder.kt
@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableVariable
 import org.jetbrains.kotlin.fir.declarations.impl.FirValueParameterImpl
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousFunctionImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousFunctionImpl.kt
index 148bad4889b..c90956a7925 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousFunctionImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousFunctionImpl.kt
@@ -13,7 +13,6 @@ import org.jetbrains.kotlin.fir.declarations.FirAnonymousFunction
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableFunction
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
@@ -41,7 +40,7 @@ internal class FirAnonymousFunctionImpl(
     override var label: FirLabel?,
     override var invocationKind: InvocationKind?,
     override val isLambda: Boolean,
-) : FirAnonymousFunction(), FirModifiableFunction<FirAnonymousFunction> {
+) : FirAnonymousFunction() {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.DECLARATIONS
 
     init {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousObjectImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousObjectImpl.kt
index de4c2833c5b..30338ea4355 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousObjectImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousObjectImpl.kt
@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.declarations.FirAnonymousObject
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableClass
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
 import org.jetbrains.kotlin.fir.symbols.impl.FirAnonymousObjectSymbol
@@ -34,7 +33,7 @@ internal class FirAnonymousObjectImpl(
     override val scopeProvider: FirScopeProvider,
     override var typeRef: FirTypeRef,
     override val symbol: FirAnonymousObjectSymbol,
-) : FirAnonymousObject(), FirModifiableClass<FirAnonymousObject> {
+) : FirAnonymousObject() {
     init {
         symbol.bind(this)
     }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirClassImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirClassImpl.kt
index 9d99b72093f..376367ae5e9 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirClassImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirClassImpl.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
@@ -14,7 +13,6 @@ import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirRegularClass
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableRegularClass
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
 import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
@@ -41,7 +39,7 @@ internal class FirClassImpl(
     override val symbol: FirRegularClassSymbol,
     override var companionObject: FirRegularClass?,
     override val superTypeRefs: MutableList<FirTypeRef>,
-) : FirPureAbstractElement(), FirRegularClass, FirModifiableRegularClass {
+) : FirRegularClass() {
     override val hasLazyNestedClassifiers: Boolean get() = false
 
     init {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirConstructorImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirConstructorImpl.kt
index 766da44bc8b..4e842ebd80e 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirConstructorImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirConstructorImpl.kt
@@ -12,7 +12,6 @@ import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableConstructor
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
@@ -42,7 +41,7 @@ internal class FirConstructorImpl(
     override val symbol: FirConstructorSymbol,
     override var delegatedConstructor: FirDelegatedConstructorCall?,
     override var body: FirBlock?,
-) : FirConstructor, FirModifiableConstructor() {
+) : FirConstructor() {
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference
     override val isPrimary: Boolean get() = false
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableClass.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableClass.kt
deleted file mode 100644
index e1972318566..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableClass.kt
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.declarations.impl
-
-import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.declarations.FirClass
-import org.jetbrains.kotlin.fir.declarations.FirDeclaration
-import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
-import org.jetbrains.kotlin.fir.symbols.impl.FirClassSymbol
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirModifiableClass<F : FirClass<F>>  : FirClass<F> {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override var resolvePhase: FirResolvePhase
-    override val symbol: FirClassSymbol<F>
-    override val classKind: ClassKind
-    override val superTypeRefs: MutableList<FirTypeRef>
-    override val declarations: MutableList<FirDeclaration>
-    override val annotations: MutableList<FirAnnotationCall>
-    override val scopeProvider: FirScopeProvider
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirModifiableClass<F>
-
-    override fun replaceResolvePhase(newResolvePhase: FirResolvePhase)
-
-    override fun replaceSuperTypeRefs(newSuperTypeRefs: List<FirTypeRef>)
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableConstructor.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableConstructor.kt
deleted file mode 100644
index 5ef582fff52..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableConstructor.kt
+++ /dev/null
@@ -1,68 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.declarations.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.declarations.FirConstructor
-import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
-import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
-import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.expressions.FirBlock
-import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
-import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
-import org.jetbrains.kotlin.fir.references.impl.FirEmptyControlFlowGraphReference
-import org.jetbrains.kotlin.fir.symbols.impl.FirConstructorSymbol
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedContainerSource
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-abstract class FirModifiableConstructor : FirPureAbstractElement(), FirConstructor, FirModifiableTypeParametersOwner {
-    abstract override val source: FirSourceElement?
-    abstract override val session: FirSession
-    abstract override var resolvePhase: FirResolvePhase
-    abstract override var returnTypeRef: FirTypeRef
-    abstract override var receiverTypeRef: FirTypeRef?
-    abstract override val typeParameters: MutableList<FirTypeParameter>
-    abstract override var controlFlowGraphReference: FirControlFlowGraphReference
-    abstract override val valueParameters: MutableList<FirValueParameter>
-    abstract override var status: FirDeclarationStatus
-    abstract override val containerSource: DeserializedContainerSource?
-    abstract override val annotations: MutableList<FirAnnotationCall>
-    abstract override val symbol: FirConstructorSymbol
-    abstract override var delegatedConstructor: FirDelegatedConstructorCall?
-    abstract override var body: FirBlock?
-    abstract override val isPrimary: Boolean
-    abstract override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirModifiableConstructor
-
-    abstract override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirModifiableConstructor
-
-    abstract override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirModifiableConstructor
-
-    abstract override fun <D> transformControlFlowGraphReference(transformer: FirTransformer<D>, data: D): FirModifiableConstructor
-
-    abstract override fun <D> transformValueParameters(transformer: FirTransformer<D>, data: D): FirModifiableConstructor
-
-    abstract override fun <D> transformStatus(transformer: FirTransformer<D>, data: D): FirModifiableConstructor
-
-    abstract override fun replaceResolvePhase(newResolvePhase: FirResolvePhase)
-
-    abstract override fun replaceReturnTypeRef(newReturnTypeRef: FirTypeRef)
-
-    abstract override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?)
-
-    abstract override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableFunction.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableFunction.kt
deleted file mode 100644
index 5ac5631ee0b..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableFunction.kt
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.declarations.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.declarations.FirFunction
-import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
-import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.expressions.FirBlock
-import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
-import org.jetbrains.kotlin.fir.references.impl.FirEmptyControlFlowGraphReference
-import org.jetbrains.kotlin.fir.symbols.impl.FirFunctionSymbol
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirModifiableFunction<F : FirFunction<F>>  : FirFunction<F> {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override var resolvePhase: FirResolvePhase
-    override val annotations: MutableList<FirAnnotationCall>
-    override var returnTypeRef: FirTypeRef
-    override var receiverTypeRef: FirTypeRef?
-    override val typeParameters: MutableList<FirTypeParameter>
-    override var controlFlowGraphReference: FirControlFlowGraphReference
-    override val symbol: FirFunctionSymbol<F>
-    override val valueParameters: MutableList<FirValueParameter>
-    override var body: FirBlock?
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirModifiableFunction<F>
-
-    override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirModifiableFunction<F>
-
-    override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirModifiableFunction<F>
-
-    override fun <D> transformControlFlowGraphReference(transformer: FirTransformer<D>, data: D): FirModifiableFunction<F>
-
-    override fun <D> transformValueParameters(transformer: FirTransformer<D>, data: D): FirModifiableFunction<F>
-
-    override fun replaceResolvePhase(newResolvePhase: FirResolvePhase)
-
-    override fun replaceReturnTypeRef(newReturnTypeRef: FirTypeRef)
-
-    override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?)
-
-    override fun replaceValueParameters(newValueParameters: List<FirValueParameter>)
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableRegularClass.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableRegularClass.kt
deleted file mode 100644
index 02580ec9a62..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableRegularClass.kt
+++ /dev/null
@@ -1,53 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.declarations.impl
-
-import org.jetbrains.kotlin.descriptors.ClassKind
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.declarations.FirDeclaration
-import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
-import org.jetbrains.kotlin.fir.declarations.FirRegularClass
-import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
-import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableClass
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
-import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirModifiableRegularClass : FirRegularClass, FirModifiableClass<FirRegularClass>, FirModifiableTypeParametersOwner {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override var resolvePhase: FirResolvePhase
-    override val annotations: MutableList<FirAnnotationCall>
-    override val typeParameters: MutableList<FirTypeParameter>
-    override var status: FirDeclarationStatus
-    override val classKind: ClassKind
-    override val declarations: MutableList<FirDeclaration>
-    override val scopeProvider: FirScopeProvider
-    override val name: Name
-    override val symbol: FirRegularClassSymbol
-    override var companionObject: FirRegularClass?
-    override val hasLazyNestedClassifiers: Boolean
-    override val superTypeRefs: MutableList<FirTypeRef>
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirModifiableRegularClass
-
-    override fun <D> transformStatus(transformer: FirTransformer<D>, data: D): FirModifiableRegularClass
-
-    override fun replaceResolvePhase(newResolvePhase: FirResolvePhase)
-
-    override fun replaceSuperTypeRefs(newSuperTypeRefs: List<FirTypeRef>)
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableTypeParametersOwner.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableTypeParametersOwner.kt
deleted file mode 100644
index 4d01ec4a9fb..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableTypeParametersOwner.kt
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.declarations.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.FirTypeParametersOwner
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirModifiableTypeParametersOwner : FirTypeParametersOwner {
-    override val source: FirSourceElement?
-    override val typeParameters: MutableList<FirTypeParameter>
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirModifiableTypeParametersOwner
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableVariable.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableVariable.kt
deleted file mode 100644
index 9fb9d6de99e..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirModifiableVariable.kt
+++ /dev/null
@@ -1,62 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.declarations.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
-import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
-import org.jetbrains.kotlin.fir.declarations.FirVariable
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.symbols.impl.FirDelegateFieldSymbol
-import org.jetbrains.kotlin.fir.symbols.impl.FirVariableSymbol
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirModifiableVariable<F : FirVariable<F>>  : FirVariable<F> {
-    override val source: FirSourceElement?
-    override val session: FirSession
-    override var resolvePhase: FirResolvePhase
-    override var returnTypeRef: FirTypeRef
-    override var receiverTypeRef: FirTypeRef?
-    override val name: Name
-    override val symbol: FirVariableSymbol<F>
-    override var initializer: FirExpression?
-    override var delegate: FirExpression?
-    override val delegateFieldSymbol: FirDelegateFieldSymbol<F>?
-    override val isVar: Boolean
-    override val isVal: Boolean
-    override var getter: FirPropertyAccessor?
-    override var setter: FirPropertyAccessor?
-    override val annotations: MutableList<FirAnnotationCall>
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun <D> transformReturnTypeRef(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun <D> transformInitializer(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun <D> transformGetter(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun <D> transformSetter(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirModifiableVariable<F>
-
-    override fun replaceResolvePhase(newResolvePhase: FirResolvePhase)
-
-    override fun replaceReturnTypeRef(newReturnTypeRef: FirTypeRef)
-
-    override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?)
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPrimaryConstructor.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPrimaryConstructor.kt
index 295e6bd2eb6..b8da93ca375 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPrimaryConstructor.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPrimaryConstructor.kt
@@ -12,7 +12,6 @@ import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableConstructor
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
@@ -42,7 +41,7 @@ internal class FirPrimaryConstructor(
     override val symbol: FirConstructorSymbol,
     override var delegatedConstructor: FirDelegatedConstructorCall?,
     override var body: FirBlock?,
-) : FirConstructor, FirModifiableConstructor() {
+) : FirConstructor() {
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference
     override val isPrimary: Boolean get() = true
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt
index 10d5087d6db..753b00c2168 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt
@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableFunction
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
@@ -42,8 +41,8 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
     override val isGetter: Boolean,
     override var status: FirDeclarationStatus,
     override val annotations: MutableList<FirAnnotationCall>,
-) : FirPropertyAccessor(), FirModifiableFunction<FirPropertyAccessor> {
-    override var receiverTypeRef: FirTypeRef? = null
+) : FirPropertyAccessor() {
+    override val receiverTypeRef: FirTypeRef? get() = null
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference
     override var contractDescription: FirContractDescription = FirEmptyContractDescription
     override val isSetter: Boolean get() = !isGetter
@@ -54,7 +53,6 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         returnTypeRef.accept(visitor, data)
-        receiverTypeRef?.accept(visitor, data)
         typeParameters.forEach { it.accept(visitor, data) }
         controlFlowGraphReference.accept(visitor, data)
         valueParameters.forEach { it.accept(visitor, data) }
@@ -66,7 +64,6 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirPropertyAccessorImpl {
         transformReturnTypeRef(transformer, data)
-        transformReceiverTypeRef(transformer, data)
         typeParameters.transformInplace(transformer, data)
         transformControlFlowGraphReference(transformer, data)
         transformValueParameters(transformer, data)
@@ -83,7 +80,6 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
     }
 
     override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirPropertyAccessorImpl {
-        receiverTypeRef = receiverTypeRef?.transformSingle(transformer, data)
         return this
     }
 
@@ -115,9 +111,7 @@ open class FirPropertyAccessorImpl @FirImplementationDetail constructor(
         returnTypeRef = newReturnTypeRef
     }
 
-    override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?) {
-        receiverTypeRef = newReceiverTypeRef
-    }
+    override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?) {}
 
     override fun replaceValueParameters(newValueParameters: List<FirValueParameter>) {
         valueParameters.clear()
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyImpl.kt
index 218dfa41f5d..2b0e69235ff 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyImpl.kt
@@ -12,8 +12,6 @@ import org.jetbrains.kotlin.fir.declarations.FirProperty
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableVariable
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
@@ -50,7 +48,7 @@ internal class FirPropertyImpl(
     override val isLocal: Boolean,
     override val typeParameters: MutableList<FirTypeParameter>,
     override var status: FirDeclarationStatus,
-) : FirProperty(), FirModifiableVariable<FirProperty>, FirModifiableTypeParametersOwner {
+) : FirProperty() {
     override val isVal: Boolean get() = !isVar
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference
     override val backingFieldSymbol: FirBackingFieldSymbol = FirBackingFieldSymbol(symbol.callableId)
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSealedClassImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSealedClassImpl.kt
index f5384509b5f..8c5e8cb9deb 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSealedClassImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSealedClassImpl.kt
@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.fir.declarations.FirRegularClass
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirSealedClass
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableRegularClass
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.scopes.FirScopeProvider
 import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
@@ -43,7 +42,7 @@ internal class FirSealedClassImpl(
     override var companionObject: FirRegularClass?,
     override val superTypeRefs: MutableList<FirTypeRef>,
     override val inheritors: MutableList<ClassId>,
-) : FirSealedClass(), FirModifiableRegularClass {
+) : FirSealedClass() {
     override val hasLazyNestedClassifiers: Boolean get() = false
 
     init {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSimpleFunctionImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSimpleFunctionImpl.kt
index adec56ea4c3..f24eb25536d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSimpleFunctionImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirSimpleFunctionImpl.kt
@@ -15,8 +15,6 @@ import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableFunction
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
@@ -46,7 +44,7 @@ open class FirSimpleFunctionImpl @FirImplementationDetail constructor(
     override val name: Name,
     override val symbol: FirFunctionSymbol<FirSimpleFunction>,
     override val annotations: MutableList<FirAnnotationCall>,
-) : FirSimpleFunction(), FirModifiableFunction<FirSimpleFunction>, FirModifiableTypeParametersOwner {
+) : FirSimpleFunction() {
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference
     override var contractDescription: FirContractDescription = FirEmptyContractDescription
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirTypeAliasImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirTypeAliasImpl.kt
index 7116ebb0c10..e27a2d28426 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirTypeAliasImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirTypeAliasImpl.kt
@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeAlias
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableTypeParametersOwner
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.symbols.impl.FirTypeAliasSymbol
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -33,7 +32,7 @@ internal class FirTypeAliasImpl(
     override val symbol: FirTypeAliasSymbol,
     override var expandedTypeRef: FirTypeRef,
     override val annotations: MutableList<FirAnnotationCall>,
-) : FirTypeAlias(), FirModifiableTypeParametersOwner {
+) : FirTypeAlias() {
     init {
         symbol.bind(this)
     }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirValueParameterImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirValueParameterImpl.kt
index 48036136afa..e725d86e230 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirValueParameterImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/declarations/impl/FirValueParameterImpl.kt
@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableVariable
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.symbols.impl.FirDelegateFieldSymbol
@@ -37,15 +36,15 @@ open class FirValueParameterImpl @FirImplementationDetail constructor(
     override val isCrossinline: Boolean,
     override val isNoinline: Boolean,
     override val isVararg: Boolean,
-) : FirValueParameter(), FirModifiableVariable<FirValueParameter> {
-    override var receiverTypeRef: FirTypeRef? = null
-    override var initializer: FirExpression? = null
-    override var delegate: FirExpression? = null
+) : FirValueParameter() {
+    override val receiverTypeRef: FirTypeRef? get() = null
+    override val initializer: FirExpression? get() = null
+    override val delegate: FirExpression? get() = null
     override val delegateFieldSymbol: FirDelegateFieldSymbol<FirValueParameter>? get() = null
     override val isVar: Boolean get() = false
     override val isVal: Boolean get() = true
-    override var getter: FirPropertyAccessor? = null
-    override var setter: FirPropertyAccessor? = null
+    override val getter: FirPropertyAccessor? get() = null
+    override val setter: FirPropertyAccessor? get() = null
 
     init {
         symbol.bind(this)
@@ -54,21 +53,12 @@ open class FirValueParameterImpl @FirImplementationDetail constructor(
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         returnTypeRef.accept(visitor, data)
-        receiverTypeRef?.accept(visitor, data)
-        initializer?.accept(visitor, data)
-        delegate?.accept(visitor, data)
-        getter?.accept(visitor, data)
-        setter?.accept(visitor, data)
         annotations.forEach { it.accept(visitor, data) }
         defaultValue?.accept(visitor, data)
     }
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirValueParameterImpl {
         transformReturnTypeRef(transformer, data)
-        transformReceiverTypeRef(transformer, data)
-        transformInitializer(transformer, data)
-        transformGetter(transformer, data)
-        transformSetter(transformer, data)
         transformOtherChildren(transformer, data)
         return this
     }
@@ -79,27 +69,22 @@ open class FirValueParameterImpl @FirImplementationDetail constructor(
     }
 
     override fun <D> transformReceiverTypeRef(transformer: FirTransformer<D>, data: D): FirValueParameterImpl {
-        receiverTypeRef = receiverTypeRef?.transformSingle(transformer, data)
         return this
     }
 
     override fun <D> transformInitializer(transformer: FirTransformer<D>, data: D): FirValueParameterImpl {
-        initializer = initializer?.transformSingle(transformer, data)
         return this
     }
 
     override fun <D> transformGetter(transformer: FirTransformer<D>, data: D): FirValueParameterImpl {
-        getter = getter?.transformSingle(transformer, data)
         return this
     }
 
     override fun <D> transformSetter(transformer: FirTransformer<D>, data: D): FirValueParameterImpl {
-        setter = setter?.transformSingle(transformer, data)
         return this
     }
 
     override fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirValueParameterImpl {
-        delegate = delegate?.transformSingle(transformer, data)
         annotations.transformInplace(transformer, data)
         defaultValue = defaultValue?.transformSingle(transformer, data)
         return this
@@ -113,7 +98,5 @@ open class FirValueParameterImpl @FirImplementationDetail constructor(
         returnTypeRef = newReturnTypeRef
     }
 
-    override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?) {
-        receiverTypeRef = newReceiverTypeRef
-    }
+    override fun replaceReceiverTypeRef(newReceiverTypeRef: FirTypeRef?) {}
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirAnnotationCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirAnnotationCall.kt
index 62e8b8046b8..cbeb9762c22 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirAnnotationCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirAnnotationCall.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions
 
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationUseSiteTarget
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirAnnotationCall : FirPureAbstractElement(), FirExpression, FirCall {
+abstract class FirAnnotationCall : FirExpression(), FirCall {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirArrayOfCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirArrayOfCall.kt
index ccedf4438df..bb4182e3be6 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirArrayOfCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirArrayOfCall.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirArrayOfCall : FirPureAbstractElement(), FirExpression, FirCall {
+abstract class FirArrayOfCall : FirExpression(), FirCall {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBinaryLogicExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBinaryLogicExpression.kt
index ff2c52a97ae..53603fa3628 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBinaryLogicExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBinaryLogicExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirBinaryLogicExpression : FirPureAbstractElement(), FirExpression {
+abstract class FirBinaryLogicExpression : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBlock.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBlock.kt
index 623e5cd4218..382a0a6b0ab 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBlock.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBlock.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirBlock : FirPureAbstractElement(), FirExpression {
+abstract class FirBlock : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val annotations: List<FirAnnotationCall>
     abstract val statements: List<FirStatement>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBreakExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBreakExpression.kt
index 995201a04a3..fcb56148912 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBreakExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirBreakExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirBreakExpression : FirPureAbstractElement(), FirLoopJump {
+abstract class FirBreakExpression : FirLoopJump() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirCheckNotNullCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirCheckNotNullCall.kt
index 9748bbfc0e3..cdcc0e088e8 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirCheckNotNullCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirCheckNotNullCall.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirCheckNotNullCall : FirPureAbstractElement(), FirExpression, FirCall, FirResolvable {
+abstract class FirCheckNotNullCall : FirExpression(), FirCall, FirResolvable {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirClassReferenceExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirClassReferenceExpression.kt
index d6d616b0b16..4e97ce734fa 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirClassReferenceExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirClassReferenceExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirClassReferenceExpression : FirPureAbstractElement(), FirExpression {
+abstract class FirClassReferenceExpression : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirConstExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirConstExpression.kt
index be90ab457c1..0653219070c 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirConstExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirConstExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirConstExpression<T> : FirPureAbstractElement(), FirExpression {
+abstract class FirConstExpression<T> : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirContinueExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirContinueExpression.kt
index 4236dcd36ec..c12145ebc61 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirContinueExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirContinueExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirContinueExpression : FirPureAbstractElement(), FirLoopJump {
+abstract class FirContinueExpression : FirLoopJump() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirDoWhileLoop.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirDoWhileLoop.kt
index 98a59c2eb00..d755c96f2fe 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirDoWhileLoop.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirDoWhileLoop.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions
 
 import org.jetbrains.kotlin.fir.FirLabel
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirDoWhileLoop : FirPureAbstractElement(), FirLoop {
+abstract class FirDoWhileLoop : FirLoop() {
     abstract override val source: FirSourceElement?
     abstract override val annotations: List<FirAnnotationCall>
     abstract override val block: FirBlock
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorExpression.kt
index 1d41498ff31..d15ebb2d6c0 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.diagnostics.FirDiagnostic
 import org.jetbrains.kotlin.fir.diagnostics.FirDiagnosticHolder
@@ -17,7 +16,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirErrorExpression : FirPureAbstractElement(), FirExpression, FirDiagnosticHolder {
+abstract class FirErrorExpression : FirExpression(), FirDiagnosticHolder {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorLoop.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorLoop.kt
index 9ac1733d26a..e82e54ec0e9 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorLoop.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirErrorLoop.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions
 
 import org.jetbrains.kotlin.fir.FirLabel
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.diagnostics.FirDiagnostic
 import org.jetbrains.kotlin.fir.diagnostics.FirDiagnosticHolder
@@ -17,7 +16,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirErrorLoop : FirPureAbstractElement(), FirLoop, FirDiagnosticHolder {
+abstract class FirErrorLoop : FirLoop(), FirDiagnosticHolder {
     abstract override val source: FirSourceElement?
     abstract override val annotations: List<FirAnnotationCall>
     abstract override val block: FirBlock
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirExpression.kt
index 148bb37b4d1..8d3b4ccbea6 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirExpression.kt
@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -14,12 +15,12 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirExpression : FirStatement {
-    override val source: FirSourceElement?
-    val typeRef: FirTypeRef
-    override val annotations: List<FirAnnotationCall>
+abstract class FirExpression : FirPureAbstractElement(), FirStatement {
+    abstract override val source: FirSourceElement?
+    abstract val typeRef: FirTypeRef
+    abstract override val annotations: List<FirAnnotationCall>
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitExpression(this, data)
 
-    fun replaceTypeRef(newTypeRef: FirTypeRef)
+    abstract fun replaceTypeRef(newTypeRef: FirTypeRef)
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirGetClassCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirGetClassCall.kt
index 7fde3dc3160..8308074b720 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirGetClassCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirGetClassCall.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirGetClassCall : FirPureAbstractElement(), FirExpression, FirCall {
+abstract class FirGetClassCall : FirExpression(), FirCall {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirJump.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirJump.kt
index 0c385f4b870..f5735434123 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirJump.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirJump.kt
@@ -16,11 +16,11 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirJump<E : FirTargetElement> : FirExpression {
-    override val source: FirSourceElement?
-    override val typeRef: FirTypeRef
-    override val annotations: List<FirAnnotationCall>
-    val target: FirTarget<E>
+abstract class FirJump<E : FirTargetElement> : FirExpression() {
+    abstract override val source: FirSourceElement?
+    abstract override val typeRef: FirTypeRef
+    abstract override val annotations: List<FirAnnotationCall>
+    abstract val target: FirTarget<E>
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitJump(this, data)
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoop.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoop.kt
index 42962ad4607..8da4a727860 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoop.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoop.kt
@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.expressions
 
 import org.jetbrains.kotlin.fir.FirAnnotationContainer
 import org.jetbrains.kotlin.fir.FirLabel
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.FirTargetElement
 import org.jetbrains.kotlin.fir.visitors.*
@@ -16,18 +17,18 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirLoop : FirStatement, FirTargetElement, FirAnnotationContainer {
-    override val source: FirSourceElement?
-    override val annotations: List<FirAnnotationCall>
-    val block: FirBlock
-    val condition: FirExpression
-    val label: FirLabel?
+abstract class FirLoop : FirPureAbstractElement(), FirStatement, FirTargetElement, FirAnnotationContainer {
+    abstract override val source: FirSourceElement?
+    abstract override val annotations: List<FirAnnotationCall>
+    abstract val block: FirBlock
+    abstract val condition: FirExpression
+    abstract val label: FirLabel?
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitLoop(this, data)
 
-    fun <D> transformBlock(transformer: FirTransformer<D>, data: D): FirLoop
+    abstract fun <D> transformBlock(transformer: FirTransformer<D>, data: D): FirLoop
 
-    fun <D> transformCondition(transformer: FirTransformer<D>, data: D): FirLoop
+    abstract fun <D> transformCondition(transformer: FirTransformer<D>, data: D): FirLoop
 
-    fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirLoop
+    abstract fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirLoop
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoopJump.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoopJump.kt
index f32fc76d3e6..742ff9e6da4 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoopJump.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirLoopJump.kt
@@ -15,11 +15,11 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-interface FirLoopJump : FirJump<FirLoop> {
-    override val source: FirSourceElement?
-    override val typeRef: FirTypeRef
-    override val annotations: List<FirAnnotationCall>
-    override val target: FirTarget<FirLoop>
+abstract class FirLoopJump : FirJump<FirLoop>() {
+    abstract override val source: FirSourceElement?
+    abstract override val typeRef: FirTypeRef
+    abstract override val annotations: List<FirAnnotationCall>
+    abstract override val target: FirTarget<FirLoop>
 
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R = visitor.visitLoopJump(this, data)
 }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirOperatorCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirOperatorCall.kt
index e7067f48bb8..f9d5a7edef4 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirOperatorCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirOperatorCall.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirOperatorCall : FirPureAbstractElement(), FirExpression, FirCall {
+abstract class FirOperatorCall : FirExpression(), FirCall {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirQualifiedAccessExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirQualifiedAccessExpression.kt
index d7539260bcc..5fb21f7cf84 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirQualifiedAccessExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirQualifiedAccessExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.types.FirTypeProjection
@@ -17,7 +16,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirQualifiedAccessExpression : FirPureAbstractElement(), FirExpression, FirQualifiedAccess {
+abstract class FirQualifiedAccessExpression : FirExpression(), FirQualifiedAccess {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedQualifier.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedQualifier.kt
index ef2a64a3441..2bbab14167c 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedQualifier.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedQualifier.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeProjection
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -18,7 +17,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirResolvedQualifier : FirPureAbstractElement(), FirExpression {
+abstract class FirResolvedQualifier : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedReifiedParameterReference.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedReifiedParameterReference.kt
index a33d818a3c7..e4881cc7e88 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedReifiedParameterReference.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirResolvedReifiedParameterReference.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.symbols.impl.FirTypeParameterSymbol
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirResolvedReifiedParameterReference : FirPureAbstractElement(), FirExpression {
+abstract class FirResolvedReifiedParameterReference : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirReturnExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirReturnExpression.kt
index a9f7d17fb88..4c58f6b737f 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirReturnExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirReturnExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.declarations.FirFunction
@@ -17,7 +16,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirReturnExpression : FirPureAbstractElement(), FirJump<FirFunction<*>> {
+abstract class FirReturnExpression : FirJump<FirFunction<*>>() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirStringConcatenationCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirStringConcatenationCall.kt
index efb08e68dde..ff41083226b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirStringConcatenationCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirStringConcatenationCall.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirStringConcatenationCall : FirPureAbstractElement(), FirCall, FirExpression {
+abstract class FirStringConcatenationCall : FirCall, FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val annotations: List<FirAnnotationCall>
     abstract override val arguments: List<FirExpression>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirThrowExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirThrowExpression.kt
index 80bac6c3c15..c5bcc1c9299 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirThrowExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirThrowExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirThrowExpression : FirPureAbstractElement(), FirExpression {
+abstract class FirThrowExpression : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTryExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTryExpression.kt
index 5a7094d267e..c7b3962683d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTryExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTryExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirTryExpression : FirPureAbstractElement(), FirExpression, FirResolvable {
+abstract class FirTryExpression : FirExpression(), FirResolvable {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTypeOperatorCall.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTypeOperatorCall.kt
index ed573a75552..ff5f5646481 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTypeOperatorCall.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirTypeOperatorCall.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirTypeOperatorCall : FirPureAbstractElement(), FirExpression, FirCall {
+abstract class FirTypeOperatorCall : FirExpression(), FirCall {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirVarargArgumentsExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirVarargArgumentsExpression.kt
index a10d992154a..317aef50a1b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirVarargArgumentsExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirVarargArgumentsExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirVarargArgumentsExpression : FirPureAbstractElement(), FirExpression {
+abstract class FirVarargArgumentsExpression : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenExpression.kt
index d292b896865..3895a4a19dd 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.declarations.FirVariable
 import org.jetbrains.kotlin.fir.references.FirReference
@@ -17,7 +16,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirWhenExpression : FirPureAbstractElement(), FirExpression, FirResolvable {
+abstract class FirWhenExpression : FirExpression(), FirResolvable {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenSubjectExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenSubjectExpression.kt
index 1adea858cba..58a039866e5 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenSubjectExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhenSubjectExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.FirWhenSubject
 import org.jetbrains.kotlin.fir.types.FirTypeRef
@@ -16,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirWhenSubjectExpression : FirPureAbstractElement(), FirExpression {
+abstract class FirWhenSubjectExpression : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhileLoop.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhileLoop.kt
index 7c33932019c..0a363206c87 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhileLoop.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWhileLoop.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions
 
 import org.jetbrains.kotlin.fir.FirLabel
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirWhileLoop : FirPureAbstractElement(), FirLoop {
+abstract class FirWhileLoop : FirLoop() {
     abstract override val source: FirSourceElement?
     abstract override val annotations: List<FirAnnotationCall>
     abstract override val label: FirLabel?
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWrappedExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWrappedExpression.kt
index c0c6a870487..7f1310f444e 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWrappedExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/FirWrappedExpression.kt
@@ -5,7 +5,6 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -15,7 +14,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-abstract class FirWrappedExpression : FirPureAbstractElement(), FirExpression {
+abstract class FirWrappedExpression : FirExpression() {
     abstract override val source: FirSourceElement?
     abstract override val typeRef: FirTypeRef
     abstract override val annotations: List<FirAnnotationCall>
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirAnnotationCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirAnnotationCallBuilder.kt
index 59025e57be0..507be340165 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirAnnotationCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirAnnotationCallBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
 import org.jetbrains.kotlin.fir.expressions.impl.FirAnnotationCallImpl
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirArrayOfCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirArrayOfCallBuilder.kt
index 730e0149b90..5300f9be9b5 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirArrayOfCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirArrayOfCallBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
 import org.jetbrains.kotlin.fir.expressions.impl.FirArrayOfCallImpl
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.*
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirBreakExpressionBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirBreakExpressionBuilder.kt
index 0641285e79d..a79baf2cbae 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirBreakExpressionBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirBreakExpressionBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirBreakExpression
 import org.jetbrains.kotlin.fir.expressions.FirLoop
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirLoopJumpBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoopJump
 import org.jetbrains.kotlin.fir.expressions.impl.FirBreakExpressionImpl
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitNothingTypeRef
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirComponentCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirComponentCallBuilder.kt
index c8e398b46b7..ae330702eac 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirComponentCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirComponentCallBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirComponentCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirComponentCallImpl
 import org.jetbrains.kotlin.fir.expressions.impl.FirNoReceiverExpression
 import org.jetbrains.kotlin.fir.references.FirNamedReference
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirContinueExpressionBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirContinueExpressionBuilder.kt
index fd5aeb06ac1..92b9afdfaf1 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirContinueExpressionBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirContinueExpressionBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirContinueExpression
 import org.jetbrains.kotlin.fir.expressions.FirLoop
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirLoopJumpBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoopJump
 import org.jetbrains.kotlin.fir.expressions.impl.FirContinueExpressionImpl
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitNothingTypeRef
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDelegatedConstructorCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDelegatedConstructorCallBuilder.kt
index 7e5934287ab..cb74a6e1a7d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDelegatedConstructorCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDelegatedConstructorCallBuilder.kt
@@ -13,7 +13,6 @@ import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirDelegatedConstructorCallImpl
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.references.impl.FirExplicitSuperReference
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDoWhileLoopBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDoWhileLoopBuilder.kt
index 7e87ff50d76..be3f31f9220 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDoWhileLoopBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirDoWhileLoopBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirDoWhileLoop
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.builder.FirLoopBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoop
 import org.jetbrains.kotlin.fir.expressions.impl.FirDoWhileLoopImpl
 import org.jetbrains.kotlin.fir.visitors.*
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirElseIfTrueConditionBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirElseIfTrueConditionBuilder.kt
index 084fe6dccce..84f2922b23d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirElseIfTrueConditionBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirElseIfTrueConditionBuilder.kt
@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.fir.expressions.builder
 
 import kotlin.contracts.*
 import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
 import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirExpressionStubBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirExpressionStubBuilder.kt
index 2df239a50db..5f94f9103d6 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirExpressionStubBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirExpressionStubBuilder.kt
@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.fir.expressions.builder
 
 import kotlin.contracts.*
 import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
 import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirFunctionCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirFunctionCallBuilder.kt
index 3409b11808d..39bc922b23b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirFunctionCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirFunctionCallBuilder.kt
@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirQualifiedAccessBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirFunctionCallImpl
 import org.jetbrains.kotlin.fir.expressions.impl.FirModifiableQualifiedAccess
 import org.jetbrains.kotlin.fir.expressions.impl.FirNoReceiverExpression
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirGetClassCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirGetClassCallBuilder.kt
index 2a0fea3e96d..aec52fd0140 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirGetClassCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirGetClassCallBuilder.kt
@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirGetClassCall
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirGetClassCallImpl
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirOperatorCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirOperatorCallBuilder.kt
index fdc1d1bb69f..de8dc9ab53b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirOperatorCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirOperatorCallBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirOperation
 import org.jetbrains.kotlin.fir.expressions.FirOperatorCall
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirOperatorCallImpl
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitBooleanTypeRef
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirStringConcatenationCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirStringConcatenationCallBuilder.kt
index b0528369ed0..ddd0a0cccef 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirStringConcatenationCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirStringConcatenationCallBuilder.kt
@@ -14,7 +14,6 @@ import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirStringConcatenationCall
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirStringConcatenationCallImpl
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitStringTypeRef
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirTypeOperatorCallBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirTypeOperatorCallBuilder.kt
index 91ed11d52f3..3942a5576c9 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirTypeOperatorCallBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirTypeOperatorCallBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirOperation
 import org.jetbrains.kotlin.fir.expressions.FirTypeOperatorCall
 import org.jetbrains.kotlin.fir.expressions.builder.FirCallBuilder
 import org.jetbrains.kotlin.fir.expressions.builder.FirExpressionBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirTypeOperatorCallImpl
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirUnitExpressionBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirUnitExpressionBuilder.kt
index 760c0f3ea21..2ad314d06e7 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirUnitExpressionBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirUnitExpressionBuilder.kt
@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.fir.expressions.builder
 
 import kotlin.contracts.*
 import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.builder.FirAnnotationContainerBuilder
 import org.jetbrains.kotlin.fir.builder.FirBuilderDsl
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirWhileLoopBuilder.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirWhileLoopBuilder.kt
index 669b9fb4010..8b49cbd6b0f 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirWhileLoopBuilder.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/builder/FirWhileLoopBuilder.kt
@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirWhileLoop
 import org.jetbrains.kotlin.fir.expressions.builder.FirLoopBuilder
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoop
 import org.jetbrains.kotlin.fir.expressions.impl.FirWhileLoopImpl
 import org.jetbrains.kotlin.fir.visitors.*
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractLoop.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractLoop.kt
deleted file mode 100644
index 8efafc20bd9..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractLoop.kt
+++ /dev/null
@@ -1,35 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.expressions.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirLabel
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.expressions.FirBlock
-import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.expressions.FirLoop
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirAbstractLoop : FirLoop {
-    override val source: FirSourceElement?
-    override val annotations: MutableList<FirAnnotationCall>
-    override var block: FirBlock
-    override var condition: FirExpression
-    override var label: FirLabel?
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirAbstractLoop
-
-    override fun <D> transformBlock(transformer: FirTransformer<D>, data: D): FirAbstractLoop
-
-    override fun <D> transformCondition(transformer: FirTransformer<D>, data: D): FirAbstractLoop
-
-    override fun <D> transformOtherChildren(transformer: FirTransformer<D>, data: D): FirAbstractLoop
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractLoopJump.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractLoopJump.kt
deleted file mode 100644
index e9042fc3648..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAbstractLoopJump.kt
+++ /dev/null
@@ -1,31 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.expressions.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.FirTarget
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.expressions.FirLoop
-import org.jetbrains.kotlin.fir.expressions.FirLoopJump
-import org.jetbrains.kotlin.fir.types.FirTypeRef
-import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirAbstractLoopJump : FirLoopJump {
-    override val source: FirSourceElement?
-    override var typeRef: FirTypeRef
-    override val annotations: MutableList<FirAnnotationCall>
-    override val target: FirTarget<FirLoop>
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirAbstractLoopJump
-
-    override fun replaceTypeRef(newTypeRef: FirTypeRef)
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAnnotationCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAnnotationCallImpl.kt
index fc2247d9bcd..e9f13ffaa98 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAnnotationCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirAnnotationCallImpl.kt
@@ -9,7 +9,6 @@ import org.jetbrains.kotlin.descriptors.annotations.AnnotationUseSiteTarget
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -24,7 +23,7 @@ internal class FirAnnotationCallImpl(
     override val arguments: MutableList<FirExpression>,
     override val useSiteTarget: AnnotationUseSiteTarget?,
     override var annotationTypeRef: FirTypeRef,
-) : FirAnnotationCall(), FirCallWithArgumentList {
+) : FirAnnotationCall() {
     override val typeRef: FirTypeRef get() = annotationTypeRef
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirArrayOfCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirArrayOfCallImpl.kt
index b7fcf66e947..3e6dfea666b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirArrayOfCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirArrayOfCallImpl.kt
@@ -9,7 +9,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirArrayOfCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.*
@@ -23,7 +22,7 @@ internal class FirArrayOfCallImpl(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
     override val arguments: MutableList<FirExpression>,
-) : FirArrayOfCall(), FirCallWithArgumentList {
+) : FirArrayOfCall() {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirBreakExpressionImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirBreakExpressionImpl.kt
index d73ebfb0bb5..4572bdbb34f 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirBreakExpressionImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirBreakExpressionImpl.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBreakExpression
 import org.jetbrains.kotlin.fir.expressions.FirLoop
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoopJump
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitNothingTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -24,7 +23,7 @@ internal class FirBreakExpressionImpl(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
     override val target: FirTarget<FirLoop>,
-) : FirBreakExpression(), FirAbstractLoopJump {
+) : FirBreakExpression() {
     override var typeRef: FirTypeRef = FirImplicitNothingTypeRef(source)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirCallWithArgumentList.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirCallWithArgumentList.kt
deleted file mode 100644
index 99daeaa6183..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirCallWithArgumentList.kt
+++ /dev/null
@@ -1,27 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.expressions.impl
-
-import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.expressions.FirCall
-import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-interface FirCallWithArgumentList : FirCall {
-    override val source: FirSourceElement?
-    override val annotations: MutableList<FirAnnotationCall>
-    override val arguments: MutableList<FirExpression>
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirCallWithArgumentList
-
-    override fun <D> transformArguments(transformer: FirTransformer<D>, data: D): FirCallWithArgumentList
-}
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirComponentCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirComponentCallImpl.kt
index 25e38ca368a..1284934fa7d 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirComponentCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirComponentCallImpl.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirComponentCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirNoReceiverExpression
 import org.jetbrains.kotlin.fir.references.FirNamedReference
 import org.jetbrains.kotlin.fir.references.impl.FirSimpleNamedReference
@@ -33,7 +32,7 @@ internal class FirComponentCallImpl(
     override val arguments: MutableList<FirExpression>,
     override var explicitReceiver: FirExpression,
     override val componentIndex: Int,
-) : FirComponentCall(), FirCallWithArgumentList {
+) : FirComponentCall() {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val safe: Boolean get() = false
     override val dispatchReceiver: FirExpression get() = FirNoReceiverExpression
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirContinueExpressionImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirContinueExpressionImpl.kt
index 86e0c62a289..d2eef1329f5 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirContinueExpressionImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirContinueExpressionImpl.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirContinueExpression
 import org.jetbrains.kotlin.fir.expressions.FirLoop
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoopJump
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitNothingTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -24,7 +23,7 @@ internal class FirContinueExpressionImpl(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
     override val target: FirTarget<FirLoop>,
-) : FirContinueExpression(), FirAbstractLoopJump {
+) : FirContinueExpression() {
     override var typeRef: FirTypeRef = FirImplicitNothingTypeRef(source)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDelegatedConstructorCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDelegatedConstructorCallImpl.kt
index 51f14c2698d..e52ff9f4156 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDelegatedConstructorCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDelegatedConstructorCallImpl.kt
@@ -9,7 +9,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.references.impl.FirExplicitSuperReference
 import org.jetbrains.kotlin.fir.references.impl.FirExplicitThisReference
@@ -27,7 +26,7 @@ internal class FirDelegatedConstructorCallImpl(
     override val arguments: MutableList<FirExpression>,
     override var constructedTypeRef: FirTypeRef,
     override val isThis: Boolean,
-) : FirDelegatedConstructorCall(), FirCallWithArgumentList {
+) : FirDelegatedConstructorCall() {
     override var calleeReference: FirReference = if (isThis) FirExplicitThisReference(source, null) else FirExplicitSuperReference(source, constructedTypeRef)
     override val isSuper: Boolean get() = !isThis
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDoWhileLoopImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDoWhileLoopImpl.kt
index fb11ef744a7..725f8820087 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDoWhileLoopImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirDoWhileLoopImpl.kt
@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirDoWhileLoop
 import org.jetbrains.kotlin.fir.expressions.FirExpression
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoop
 import org.jetbrains.kotlin.fir.visitors.*
 
 /*
@@ -25,7 +24,7 @@ internal class FirDoWhileLoopImpl(
     override var block: FirBlock,
     override var condition: FirExpression,
     override var label: FirLabel?,
-) : FirDoWhileLoop(), FirAbstractLoop {
+) : FirDoWhileLoop() {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         annotations.forEach { it.accept(visitor, data) }
         block.accept(visitor, data)
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirElseIfTrueCondition.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirElseIfTrueCondition.kt
index 19bf7961ad2..a58bc331f5b 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirElseIfTrueCondition.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirElseIfTrueCondition.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -22,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirElseIfTrueCondition @FirImplementationDetail constructor(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
-) : FirPureAbstractElement(), FirExpression {
+) : FirExpression() {
     override var typeRef: FirTypeRef = FirImplicitBooleanTypeRef(source)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirExpressionStub.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirExpressionStub.kt
index c98c2ffac8a..ab8b0456278 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirExpressionStub.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirExpressionStub.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -22,7 +21,7 @@ class FirExpressionStub @FirImplementationDetail constructor(
     override val source: FirSourceElement?,
     override var typeRef: FirTypeRef,
     override val annotations: MutableList<FirAnnotationCall>,
-) : FirPureAbstractElement(), FirExpression {
+) : FirExpression() {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         typeRef.accept(visitor, data)
         annotations.forEach { it.accept(visitor, data) }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirFunctionCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirFunctionCallImpl.kt
index 522eb599f16..f675348147a 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirFunctionCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirFunctionCallImpl.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.expressions.impl.FirModifiableQualifiedAccess
 import org.jetbrains.kotlin.fir.references.FirNamedReference
 import org.jetbrains.kotlin.fir.types.FirTypeProjection
@@ -33,7 +32,7 @@ open class FirFunctionCallImpl @FirImplementationDetail constructor(
     override var extensionReceiver: FirExpression,
     override val arguments: MutableList<FirExpression>,
     override var calleeReference: FirNamedReference,
-) : FirFunctionCall(), FirModifiableQualifiedAccess, FirCallWithArgumentList {
+) : FirFunctionCall(), FirModifiableQualifiedAccess {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         typeRef.accept(visitor, data)
         annotations.forEach { it.accept(visitor, data) }
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirGetClassCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirGetClassCallImpl.kt
index 09aebbe3fd7..b433d2740f7 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirGetClassCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirGetClassCallImpl.kt
@@ -9,7 +9,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirGetClassCall
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.*
@@ -23,7 +22,7 @@ internal class FirGetClassCallImpl(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
     override val arguments: MutableList<FirExpression>,
-) : FirGetClassCall(), FirCallWithArgumentList {
+) : FirGetClassCall() {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val argument: FirExpression get() = arguments.first()
 
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirOperatorCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirOperatorCallImpl.kt
index ea62008cbd8..2f99d9aaeae 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirOperatorCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirOperatorCallImpl.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirOperation
 import org.jetbrains.kotlin.fir.expressions.FirOperatorCall
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitBooleanTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
@@ -26,7 +25,7 @@ internal class FirOperatorCallImpl(
     override val annotations: MutableList<FirAnnotationCall>,
     override val arguments: MutableList<FirExpression>,
     override val operation: FirOperation,
-) : FirOperatorCall(), FirCallWithArgumentList {
+) : FirOperatorCall() {
     override var typeRef: FirTypeRef = if (operation in FirOperation.BOOLEANS) {
         FirImplicitBooleanTypeRef(null)
     } else {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirStringConcatenationCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirStringConcatenationCallImpl.kt
index 2e7e0d32fd2..ea980cf387a 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirStringConcatenationCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirStringConcatenationCallImpl.kt
@@ -9,7 +9,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirStringConcatenationCall
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitStringTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -23,7 +22,7 @@ internal class FirStringConcatenationCallImpl(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
     override val arguments: MutableList<FirExpression>,
-) : FirStringConcatenationCall(), FirCallWithArgumentList {
+) : FirStringConcatenationCall() {
     override var typeRef: FirTypeRef = FirImplicitStringTypeRef(source)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirTypeOperatorCallImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirTypeOperatorCallImpl.kt
index da278308736..c655877f9b8 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirTypeOperatorCallImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirTypeOperatorCallImpl.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirOperation
 import org.jetbrains.kotlin.fir.expressions.FirTypeOperatorCall
-import org.jetbrains.kotlin.fir.expressions.impl.FirCallWithArgumentList
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.*
@@ -26,7 +25,7 @@ internal class FirTypeOperatorCallImpl(
     override val arguments: MutableList<FirExpression>,
     override val operation: FirOperation,
     override var conversionTypeRef: FirTypeRef,
-) : FirTypeOperatorCall(), FirCallWithArgumentList {
+) : FirTypeOperatorCall() {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirUnitExpression.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirUnitExpression.kt
index d71a2eff714..9d3c57f6275 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirUnitExpression.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirUnitExpression.kt
@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import org.jetbrains.kotlin.fir.FirImplementationDetail
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -22,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirUnitExpression @FirImplementationDetail constructor(
     override val source: FirSourceElement?,
     override val annotations: MutableList<FirAnnotationCall>,
-) : FirPureAbstractElement(), FirExpression {
+) : FirExpression() {
     override var typeRef: FirTypeRef = FirImplicitUnitTypeRef(source)
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirWhileLoopImpl.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirWhileLoopImpl.kt
index a573b3e14b2..03ddfcb555f 100644
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirWhileLoopImpl.kt
+++ b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/expressions/impl/FirWhileLoopImpl.kt
@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirWhileLoop
-import org.jetbrains.kotlin.fir.expressions.impl.FirAbstractLoop
 import org.jetbrains.kotlin.fir.visitors.*
 
 /*
@@ -25,7 +24,7 @@ internal class FirWhileLoopImpl(
     override var label: FirLabel?,
     override var condition: FirExpression,
     override var block: FirBlock,
-) : FirWhileLoop(), FirAbstractLoop {
+) : FirWhileLoop() {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         annotations.forEach { it.accept(visitor, data) }
         label?.accept(visitor, data)
diff --git a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/impl/FirAbstractAnnotatedElement.kt b/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/impl/FirAbstractAnnotatedElement.kt
deleted file mode 100644
index 81a7a8f72ef..00000000000
--- a/compiler/fir/tree/gen/org/jetbrains/kotlin/fir/impl/FirAbstractAnnotatedElement.kt
+++ /dev/null
@@ -1,31 +0,0 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.impl
-
-import org.jetbrains.kotlin.fir.FirAnnotationContainer
-import org.jetbrains.kotlin.fir.FirPureAbstractElement
-import org.jetbrains.kotlin.fir.FirSourceElement
-import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
-import org.jetbrains.kotlin.fir.visitors.*
-
-/*
- * This file was generated automatically
- * DO NOT MODIFY IT MANUALLY
- */
-
-internal class FirAbstractAnnotatedElement(
-    override val source: FirSourceElement?,
-    override val annotations: MutableList<FirAnnotationCall>,
-) : FirPureAbstractElement(), FirAnnotationContainer {
-    override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
-        annotations.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirAbstractAnnotatedElement {
-        annotations.transformInplace(transformer, data)
-        return this
-    }
-}
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationUtil.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationUtil.kt
index e5cd79ec4e0..4cbbad7d366 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationUtil.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirDeclarationUtil.kt
@@ -8,11 +8,8 @@ package org.jetbrains.kotlin.fir.declarations
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.fir.declarations.builder.AbstractFirRegularClassBuilder
 import org.jetbrains.kotlin.fir.declarations.builder.FirTypeParameterBuilder
-import org.jetbrains.kotlin.fir.declarations.impl.FirModifiableRegularClass
-import org.jetbrains.kotlin.fir.declarations.impl.FirTypeParameterImpl
 import org.jetbrains.kotlin.fir.symbols.impl.FirAnonymousObjectSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirClassSymbol
-import org.jetbrains.kotlin.fir.symbols.impl.FirPropertySymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
 import org.jetbrains.kotlin.fir.types.ConeClassLikeType
 import org.jetbrains.kotlin.fir.types.coneTypeSafe
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirNoReceiverExpression.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirNoReceiverExpression.kt
index a414c337ad8..20bc10ae3de 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirNoReceiverExpression.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirNoReceiverExpression.kt
@@ -14,7 +14,7 @@ import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.FirTransformer
 import org.jetbrains.kotlin.fir.visitors.FirVisitor
 
-object FirNoReceiverExpression : FirPureAbstractElement(), FirExpression {
+object FirNoReceiverExpression : FirExpression() {
     override val source: FirSourceElement? = null
     override val typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: List<FirAnnotationCall> get() = emptyList()
diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirSingleExpressionBlock.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirSingleExpressionBlock.kt
index c00b90929c9..76a6dcca08b 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirSingleExpressionBlock.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirSingleExpressionBlock.kt
@@ -10,7 +10,6 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirStatement
-import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.FirTransformer
diff --git a/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/ImplementationConfigurator.kt b/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/ImplementationConfigurator.kt
index 02131b5257b..222ffa1d7d8 100644
--- a/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/ImplementationConfigurator.kt
+++ b/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/ImplementationConfigurator.kt
@@ -12,8 +12,6 @@ import org.jetbrains.kotlin.fir.tree.generator.model.Implementation.Kind.OpenCla
 import org.jetbrains.kotlin.fir.tree.generator.util.traverseParents
 
 object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator() {
-    private lateinit var abstractAnnotatedElement: Implementation
-
     fun configureImplementations() {
         configure()
         generateDefaultImplementations(FirTreeBuilder)
@@ -21,18 +19,7 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
     }
 
     private fun configure() = with(FirTreeBuilder) {
-        val callWithArgumentList = impl(call, "FirCallWithArgumentList")
-
-        abstractAnnotatedElement = impl(annotationContainer, "FirAbstractAnnotatedElement")
-
-        val modifiableTypeParametersOwner = impl(typeParametersOwner, "FirModifiableTypeParametersOwner")
-
-        val modifiableConstructor = impl(constructor, "FirModifiableConstructor") {
-            parents += modifiableTypeParametersOwner
-        }
-
         impl(constructor) {
-            parents += modifiableConstructor
             defaultFalse("isPrimary", withGetter = true)
             default("typeParameters") {
                 needAcceptAndTransform = false
@@ -40,8 +27,6 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         }
 
         impl(constructor, "FirPrimaryConstructor") {
-            parents += modifiableConstructor
-
             defaultTrue("isPrimary", withGetter = true)
             default("typeParameters") {
                 needAcceptAndTransform = false
@@ -52,15 +37,7 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         noImpl(declarationStatus)
         noImpl(resolvedDeclarationStatus)
 
-        val modifiableClass = impl(klass, "FirModifiableClass")
-
-        val modifiableRegularClass = impl(regularClass, "FirModifiableRegularClass") {
-            parents += modifiableClass.withArg(regularClass)
-            parents += modifiableTypeParametersOwner
-        }
-
         val regularClassConfig: ImplementationContext.() -> Unit = {
-            parents += modifiableRegularClass
             defaultFalse("hasLazyNestedClassifiers", withGetter = true)
         }
 
@@ -68,13 +45,9 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
 
         impl(sealedClass, config = regularClassConfig)
 
-        impl(anonymousObject) {
-            parents += modifiableClass.withArg(anonymousObject)
-        }
+        impl(anonymousObject)
 
-        impl(typeAlias) {
-            parents += modifiableTypeParametersOwner
-        }
+        impl(typeAlias)
 
         impl(import)
 
@@ -103,16 +76,13 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         }
 
         impl(annotationCall) {
-            parents += callWithArgumentList
             default("typeRef") {
                 value = "annotationTypeRef"
                 withGetter = true
             }
         }
 
-        impl(arrayOfCall) {
-            parents += callWithArgumentList
-        }
+        impl(arrayOfCall)
 
         val modifiableQualifiedAccess = impl(qualifiedAccessWithoutCallee, "FirModifiableQualifiedAccess") {
             isMutable("safe")
@@ -135,7 +105,6 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         }
 
         impl(componentCall) {
-            parents += callWithArgumentList // modifiableQualifiedAccess
             default("safe") {
                 value = "false"
                 withGetter = true
@@ -151,18 +120,11 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             optInToInternals()
         }
 
-        val abstractLoop = impl(loop, "FirAbstractLoop")
+        impl(whileLoop)
 
-        impl(whileLoop) {
-            parents += abstractLoop
-        }
-
-        impl(doWhileLoop) {
-            parents += abstractLoop
-        }
+        impl(doWhileLoop)
 
         impl(delegatedConstructorCall) {
-            parents += callWithArgumentList
             default(
                 "calleeReference",
                 "if (isThis) FirExplicitThisReference(source, null) else FirExplicitSuperReference(source, constructedTypeRef)"
@@ -174,7 +136,7 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             useTypes(explicitThisReferenceType, explicitSuperReferenceType)
         }
 
-        val elseIfTrueCondition = impl(expression, "FirElseIfTrueCondition") {
+        impl(expression, "FirElseIfTrueCondition") {
             default("typeRef", "FirImplicitBooleanTypeRef(source)")
             useTypes(implicitBooleanTypeRefType)
             publicImplementation()
@@ -201,7 +163,6 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
 
         impl(functionCall) {
             parents += modifiableQualifiedAccess
-            parents += callWithArgumentList
             kind = OpenClass
         }
 
@@ -213,18 +174,13 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         noImpl(expressionWithSmartcast)
 
         impl(getClassCall) {
-            parents += callWithArgumentList
             default("argument") {
                 value = "arguments.first()"
                 withGetter = true
             }
         }
 
-        val modifiableVariable = impl(variable, "FirModifiableVariable")
-
         impl(property) {
-            parents += modifiableVariable.withArg(property)
-            parents += modifiableTypeParametersOwner
             default("isVal") {
                 value = "!isVar"
                 withGetter = true
@@ -276,7 +232,6 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         }
 
         impl(operatorCall) {
-            parents += callWithArgumentList
             default("typeRef", """
                 |if (operation in FirOperation.BOOLEANS) {
                 |        FirImplicitBooleanTypeRef(null)
@@ -288,9 +243,7 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             useTypes(implicitTypeRefType, implicitBooleanTypeRefType)
         }
 
-        impl(typeOperatorCall) {
-            parents += callWithArgumentList
-        }
+        impl(typeOperatorCall)
 
         impl(resolvedQualifier) {
             isMutable("packageFqName", "relativeClassFqName", "safe")
@@ -312,7 +265,6 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         }
 
         impl(stringConcatenationCall) {
-            parents += callWithArgumentList
             default("typeRef", "FirImplicitStringTypeRef(source)")
             useTypes(implicitStringTypeRefType)
         }
@@ -346,15 +298,11 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             }
         }
 
-        val modifiableFunction = impl(function, "FirModifiableFunction")
-
         impl(anonymousFunction) {
-            parents += modifiableFunction.withArg(anonymousFunction)
             default("resolvePhase", "FirResolvePhase.DECLARATIONS")
         }
 
         impl(propertyAccessor) {
-            parents += modifiableFunction.withArg(propertyAccessor)
             default("receiverTypeRef") {
                 value = "null"
                 withGetter = true
@@ -493,23 +441,18 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
             noSource()
         }
 
-        val abstractLoopJump = impl(loopJump, "FirAbstractLoopJump") {}
-
         impl(breakExpression) {
-            parents += abstractLoopJump
             default("typeRef", "FirImplicitNothingTypeRef(source)")
             useTypes(implicitNothingTypeRefType)
         }
 
         impl(continueExpression) {
-            parents += abstractLoopJump
             default("typeRef", "FirImplicitNothingTypeRef(source)")
             useTypes(implicitNothingTypeRefType)
         }
 
         impl(valueParameter) {
             kind = OpenClass
-            parents += modifiableVariable.withArg(valueParameter)
             defaultTrue("isVal", withGetter = true)
             defaultFalse("isVar", withGetter = true)
             defaultNull("getter", "setter", "initializer", "delegate", "receiverTypeRef", "delegateFieldSymbol", withGetter = true)
@@ -521,8 +464,6 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
 
         impl(simpleFunction) {
             kind = OpenClass
-            parents += modifiableFunction.withArg(simpleFunction)
-            parents += modifiableTypeParametersOwner
             default("contractDescription", "FirEmptyContractDescription")
             useTypes(emptyContractDescriptionType)
         }
diff --git a/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/Main.kt b/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/Main.kt
index b7ce3d4a393..922cf17a26d 100644
--- a/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/Main.kt
+++ b/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/Main.kt
@@ -11,9 +11,8 @@ import java.io.File
 
 
 fun main(args: Array<String>) {
-//    val generationPath = args.firstOrNull()?.let { File(it) }
-//        ?: File("/home/demiurg/Programming/kotlin/kotlin/compiler/fir/tree/gen").absoluteFile
-    val generationPath = File("/home/demiurg/Programming/kotlin/kotlin/compiler/fir/tree/gen").absoluteFile
+    val generationPath = args.firstOrNull()?.let { File(it) }
+        ?: File("compiler/fir/tree/gen").absoluteFile
 
     NodeConfigurator.configureFields()
     detectBaseTransformerTypes(FirTreeBuilder)
@@ -25,5 +24,3 @@ fun main(args: Array<String>) {
 //    printFieldUsageTable(FirTreeBuilder)
 //    printHierarchyGraph(FirTreeBuilder)
 }
-
-// FirTreeBuilder.constExpression.fields.first()
\ No newline at end of file
diff --git a/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/util/HierachyGraphGenerator.kt b/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/util/HierachyGraphGenerator.kt
index 81753b0f889..30d44bdd0cd 100644
--- a/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/util/HierachyGraphGenerator.kt
+++ b/compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/util/HierachyGraphGenerator.kt
@@ -15,7 +15,7 @@ fun printHierarchyGraph(builder: AbstractFirTreeBuilder) {
         else -> "red"
     }
 
-    val elements = builder.elements + builder.elements.flatMap { it.allParents }
+    val elements = builder.elements
 
     data class Edge(val from: String, val to: String) {
         override fun toString(): String {
@@ -23,6 +23,10 @@ fun printHierarchyGraph(builder: AbstractFirTreeBuilder) {
         }
     }
 
+    val (interfaces, classes) = elements.partition { it.kind == Implementation.Kind.Interface }
+    println("Interfaces: ${interfaces.size}")
+    println("Classes: ${classes.size}")
+
     File("FirTree.dot").printWriter().use { printer ->
         with(printer) {
             println("digraph FirTree {")