[FIR] Add FirAbstractElement as base type for all fir node implementations

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaClass.kt

@@ -9,6 +9,7 @@ import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibility
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.impl.FirDeclarationStatusImpl
@@ -34,7 +35,7 @@ class FirJavaClass internal constructor(
     isTopLevel: Boolean,
     isStatic: Boolean,
     internal val javaTypeParameterStack: JavaTypeParameterStack
-) : FirRegularClass, FirModifiableClass {
+) : FirPureAbstractElement(), FirRegularClass, FirModifiableClass {
     override var status: FirDeclarationStatusImpl = FirDeclarationStatusImpl(visibility, modality)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaConstructor.kt

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibility
 import org.jetbrains.kotlin.fir.CONSTRUCTOR_NAME
 import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.impl.FirDeclarationStatusImpl
@@ -36,7 +37,7 @@ class FirJavaConstructor(
     override val isPrimary: Boolean,
     isInner: Boolean,
     override var returnTypeRef : FirTypeRef
-) : FirAbstractAnnotatedElement, FirConstructor {
+) : FirPureAbstractElement(), FirAbstractAnnotatedElement, FirConstructor {
     override val receiverTypeRef: FirTypeRef? get() = null
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()
     override val name: Name get() = CONSTRUCTOR_NAME

compiler/fir/java/src/org/jetbrains/kotlin/fir/java/declarations/FirJavaField.kt

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibility
 import org.jetbrains.kotlin.fir.FirAnnotationContainer
 import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.impl.FirDeclarationStatusImpl
@@ -36,7 +37,7 @@ class FirJavaField(
     override var returnTypeRef: FirTypeRef,
     override val isVar: Boolean,
     isStatic: Boolean
-) : FirAbstractAnnotatedElement, FirField {
+) : FirPureAbstractElement(), FirAbstractAnnotatedElement, FirField {
     init {
         symbol.bind(this)
     }

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/FirControlFlowGraphReferenceImpl.kt

@@ -7,12 +7,13 @@ package org.jetbrains.kotlin.fir.resolve.dfa
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
 import org.jetbrains.kotlin.fir.resolve.dfa.cfg.ControlFlowGraph
 import org.jetbrains.kotlin.fir.visitors.FirTransformer
 import org.jetbrains.kotlin.fir.visitors.FirVisitor
 
-class FirControlFlowGraphReferenceImpl(val controlFlowGraph: ControlFlowGraph) : FirControlFlowGraphReference {
+class FirControlFlowGraphReferenceImpl(val controlFlowGraph: ControlFlowGraph) : FirPureAbstractElement(), FirControlFlowGraphReference {
     override val psi: PsiElement? get() = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/FirPureAbstractElement.kt

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2010-2019 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
+
+import org.jetbrains.kotlin.fir.visitors.FirTransformer
+import org.jetbrains.kotlin.fir.visitors.FirVisitor
+
+abstract class FirPureAbstractElement : FirElement {
+    abstract override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D)
+
+    abstract override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirElement
+}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousFunctionImpl.kt

@@ -8,6 +8,7 @@ package org.jetbrains.kotlin.fir.declarations.impl
 import com.intellij.psi.PsiElement
 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.declarations.FirAnonymousFunction
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -34,7 +35,7 @@ class FirAnonymousFunctionImpl(
     override var returnTypeRef: FirTypeRef,
     override var receiverTypeRef: FirTypeRef?,
     override val symbol: FirAnonymousFunctionSymbol
-) : FirAnonymousFunction, FirModifiableFunction<FirAnonymousFunction>, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirAnonymousFunction, FirModifiableFunction<FirAnonymousFunction>, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.DECLARATIONS
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousInitializerImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirAnonymousInitializer
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -21,7 +22,7 @@ class FirAnonymousInitializerImpl(
     override val psi: PsiElement?,
     override val session: FirSession,
     override var body: FirBlock?
-) : FirAnonymousInitializer {
+) : FirPureAbstractElement(), FirAnonymousInitializer {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirAnonymousObjectImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirAnonymousObject
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
@@ -25,7 +26,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirAnonymousObjectImpl(
     override val psi: PsiElement?,
     override val session: FirSession
-) : FirAnonymousObject, FirModifiableClass, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirAnonymousObject, FirModifiableClass, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val classKind: ClassKind get() = ClassKind.OBJECT
     override val superTypeRefs: MutableList<FirTypeRef> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirClassImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
@@ -33,7 +34,7 @@ class FirClassImpl(
     override var status: FirDeclarationStatus,
     override val classKind: ClassKind,
     override val symbol: FirClassSymbol
-) : FirRegularClass, FirModifiableRegularClass, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirRegularClass, FirModifiableRegularClass, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirConstructorImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirConstructor
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
@@ -36,7 +37,7 @@ open class FirConstructorImpl(
     override var receiverTypeRef: FirTypeRef?,
     override var status: FirDeclarationStatus,
     override val symbol: FirConstructorSymbol
-) : FirConstructor, FirModifiableConstructor, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirConstructor, FirModifiableConstructor, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference()
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirDeclarationStatusImpl.kt

@@ -8,6 +8,7 @@ package org.jetbrains.kotlin.fir.declarations.impl
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibility
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.impl.FirDeclarationStatusImpl.Modifier.*
 import org.jetbrains.kotlin.fir.visitors.FirTransformer
@@ -16,7 +17,7 @@ import org.jetbrains.kotlin.fir.visitors.FirVisitor
 open class FirDeclarationStatusImpl(
     override val visibility: Visibility,
     override val modality: Modality?
-) : FirDeclarationStatus {
+) : FirPureAbstractElement(), FirDeclarationStatus {
     override val psi: PsiElement? get() = null
     protected var flags: Int = 0
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirDefaultSetterValueParameter.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -29,7 +30,7 @@ class FirDefaultSetterValueParameter(
     override val session: FirSession,
     override var returnTypeRef: FirTypeRef,
     override val symbol: FirVariableSymbol<FirValueParameter>
-) : FirValueParameter, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirValueParameter, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override var receiverTypeRef: FirTypeRef? = null
     override val name: Name = Name.identifier("value")

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirEnumEntryImpl.kt

@@ -9,6 +9,7 @@ import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
@@ -35,7 +36,7 @@ class FirEnumEntryImpl(
     override val session: FirSession,
     override val name: Name,
     override val symbol: FirClassSymbol
-) : FirEnumEntry, FirModifiableClass, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirEnumEntry, FirModifiableClass, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirErrorFunctionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirErrorFunction
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -31,7 +32,7 @@ class FirErrorFunctionImpl(
     override val session: FirSession,
     override val reason: String,
     override val symbol: FirErrorFunctionSymbol
-) : FirErrorFunction, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirErrorFunction, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var returnTypeRef: FirTypeRef = FirErrorTypeRefImpl(null, reason)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirFileImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirFile
@@ -26,7 +27,7 @@ class FirFileImpl(
     override val session: FirSession,
     override val name: String,
     override val packageFqName: FqName
-) : FirFile, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirFile, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val imports: MutableList<FirImport> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirImportImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirImport
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
@@ -21,7 +22,7 @@ class FirImportImpl(
     override val importedFqName: FqName?,
     override val isAllUnder: Boolean,
     override val aliasName: Name?
-) : FirImport {
+) : FirPureAbstractElement(), FirImport {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirImportImpl {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyAccessorImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
@@ -34,7 +35,7 @@ open class FirPropertyAccessorImpl(
     override val symbol: FirPropertyAccessorSymbol,
     override val isGetter: Boolean,
     override var status: FirDeclarationStatus
-) : FirPropertyAccessor, FirModifiableFunction<FirPropertyAccessor>, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirPropertyAccessor, FirModifiableFunction<FirPropertyAccessor>, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override var receiverTypeRef: FirTypeRef? = null
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirPropertyImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirProperty
@@ -42,7 +43,7 @@ class FirPropertyImpl(
     override val symbol: FirPropertySymbol,
     override val isLocal: Boolean,
     override var status: FirDeclarationStatus
-) : FirProperty, FirModifiableVariable<FirProperty>, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirProperty, FirModifiableVariable<FirProperty>, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = if (isLocal) FirResolvePhase.DECLARATIONS else FirResolvePhase.RAW_FIR
     override val delegateFieldSymbol: FirDelegateFieldSymbol<FirProperty>? = delegate?.let { FirDelegateFieldSymbol(symbol.callableId) }
     override val isVal: Boolean get() = !isVar

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirResolvedImportImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirImport
 import org.jetbrains.kotlin.fir.declarations.FirResolvedImport
 import org.jetbrains.kotlin.name.ClassId
@@ -22,7 +23,7 @@ class FirResolvedImportImpl(
     override var delegate: FirImport,
     override val packageFqName: FqName,
     override val relativeClassName: FqName?
-) : FirResolvedImport {
+) : FirPureAbstractElement(), FirResolvedImport {
     override val psi: PsiElement? get() = delegate.psi
     override val importedFqName: FqName? get() = delegate.importedFqName
     override val isAllUnder: Boolean get() = delegate.isAllUnder

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirSealedClassImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclaration
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
@@ -35,7 +36,7 @@ class FirSealedClassImpl(
     override var status: FirDeclarationStatus,
     override val classKind: ClassKind,
     override val symbol: FirClassSymbol
-) : FirSealedClass, FirModifiableRegularClass, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirSealedClass, FirModifiableRegularClass, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirSimpleFunctionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -36,7 +37,7 @@ open class FirSimpleFunctionImpl(
     override val name: Name,
     override var status: FirDeclarationStatus,
     override val symbol: FirFunctionSymbol<FirSimpleFunction>
-) : FirSimpleFunction, FirModifiableFunction<FirSimpleFunction>, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirSimpleFunction, FirModifiableFunction<FirSimpleFunction>, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override var controlFlowGraphReference: FirControlFlowGraphReference = FirEmptyControlFlowGraphReference()
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirTypeAliasImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirDeclarationStatus
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -31,7 +32,7 @@ class FirTypeAliasImpl(
     override var status: FirDeclarationStatus,
     override val symbol: FirTypeAliasSymbol,
     override var expandedTypeRef: FirTypeRef
-) : FirTypeAlias, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirTypeAlias, FirModifiableTypeParametersOwner, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val typeParameters: MutableList<FirTypeParameter> = mutableListOf()
     override var supertypesComputationStatus: SupertypesComputationStatus = SupertypesComputationStatus.NOT_COMPUTED

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirTypeParameterImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.declarations.FirTypeParameter
@@ -29,7 +30,7 @@ class FirTypeParameterImpl(
     override val symbol: FirTypeParameterSymbol,
     override val variance: Variance,
     override val isReified: Boolean
-) : FirTypeParameter, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirTypeParameter, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override val bounds: MutableList<FirTypeRef> = mutableListOf()
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/impl/FirValueParameterImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.declarations.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
@@ -34,7 +35,7 @@ open class FirValueParameterImpl(
     override val isCrossinline: Boolean,
     override val isNoinline: Boolean,
     override val isVararg: Boolean
-) : FirValueParameter, FirModifiableVariable<FirValueParameter>, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirValueParameter, FirModifiableVariable<FirValueParameter>, FirAbstractAnnotatedElement {
     override var resolvePhase: FirResolvePhase = FirResolvePhase.RAW_FIR
     override var receiverTypeRef: FirTypeRef? = null
     override var initializer: FirExpression? = null

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirAnnotationCallImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationUseSiteTarget
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -22,7 +23,7 @@ class FirAnnotationCallImpl(
     override val psi: PsiElement?,
     override val useSiteTarget: AnnotationUseSiteTarget?,
     override var annotationTypeRef: FirTypeRef
-) : FirAnnotationCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirAnnotationCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override val typeRef: FirTypeRef get() = annotationTypeRef
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val arguments: MutableList<FirExpression> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirArrayOfCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirArrayOfCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirArrayOfCallImpl(
     override val psi: PsiElement?
-) : FirArrayOfCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirArrayOfCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val arguments: MutableList<FirExpression> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirArraySetCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirArraySetCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -23,7 +24,7 @@ class FirArraySetCallImpl(
     override val psi: PsiElement?,
     override var rValue: FirExpression,
     override val operation: FirOperation
-) : FirArraySetCall, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirArraySetCall, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var safe: Boolean = false
     override var explicitReceiver: FirExpression? = null

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirBinaryLogicExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBinaryLogicExpression
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -25,7 +26,7 @@ class FirBinaryLogicExpressionImpl(
     override var leftOperand: FirExpression,
     override var rightOperand: FirExpression,
     override val kind: LogicOperationKind
-) : FirBinaryLogicExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirBinaryLogicExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirBlockImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirStatement
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirBlockImpl(
     override val psi: PsiElement?
-) : FirBlock, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirBlock, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val statements: MutableList<FirStatement> = mutableListOf()
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirBreakExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBreakExpression
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirBreakExpressionImpl(
     override val psi: PsiElement?
-) : FirBreakExpression, FirAbstractLoopJump, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirBreakExpression, FirAbstractLoopJump, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitNothingTypeRef(psi)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override lateinit var target: FirTarget<FirLoop>

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirCallableReferenceAccessImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirCallableReferenceAccess
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirCallableReferenceAccessImpl(
     override val psi: PsiElement?
-) : FirCallableReferenceAccess, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirCallableReferenceAccess, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var safe: Boolean = false

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirCatchImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirCatch
@@ -20,7 +21,7 @@ class FirCatchImpl(
     override val psi: PsiElement?,
     override var parameter: FirValueParameter,
     override var block: FirBlock
-) : FirCatch {
+) : FirPureAbstractElement(), FirCatch {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         parameter.accept(visitor, data)
         block.accept(visitor, data)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirClassReferenceExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirClassReferenceExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirClassReferenceExpressionImpl(
     override val psi: PsiElement?,
     override var classTypeRef: FirTypeRef
-) : FirClassReferenceExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirClassReferenceExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirComponentCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirComponentCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -27,7 +28,7 @@ class FirComponentCallImpl(
     override val psi: PsiElement?,
     override var explicitReceiver: FirExpression,
     override val componentIndex: Int
-) : FirComponentCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirComponentCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val safe: Boolean get() = false

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirConstExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirConstExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -23,7 +24,7 @@ class FirConstExpressionImpl<T> (
     override val psi: PsiElement?,
     override val kind: IrConstKind<T>,
     override val value: T
-) : FirConstExpression<T>, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirConstExpression<T>, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirContinueExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirContinueExpression
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirContinueExpressionImpl(
     override val psi: PsiElement?
-) : FirContinueExpression, FirAbstractLoopJump, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirContinueExpression, FirAbstractLoopJump, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitNothingTypeRef(psi)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override lateinit var target: FirTarget<FirLoop>

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirDelegatedConstructorCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirDelegatedConstructorCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -25,7 +26,7 @@ class FirDelegatedConstructorCallImpl(
     override val psi: PsiElement?,
     override var constructedTypeRef: FirTypeRef,
     override val isThis: Boolean
-) : FirDelegatedConstructorCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirDelegatedConstructorCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val arguments: MutableList<FirExpression> = mutableListOf()
     override val isSuper: Boolean get() = !isThis

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirDoWhileLoopImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirLabel
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirDoWhileLoop
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirDoWhileLoopImpl(
     override val psi: PsiElement?,
     override var condition: FirExpression
-) : FirDoWhileLoop, FirAbstractLoop, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirDoWhileLoop, FirAbstractLoop, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override lateinit var block: FirBlock
     override var label: FirLabel? = null

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirElseIfTrueCondition.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -20,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirElseIfTrueCondition(
     override val psi: PsiElement?
-) : FirExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitBooleanTypeRef(psi)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirEmptyExpressionBlock.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirStatement
@@ -19,7 +20,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-class FirEmptyExpressionBlock : FirBlock, FirAbstractAnnotatedElement {
+class FirEmptyExpressionBlock : FirPureAbstractElement(), FirBlock, FirAbstractAnnotatedElement {
     override val psi: PsiElement? = null
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val statements: MutableList<FirStatement> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirErrorExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirErrorExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirErrorExpressionImpl(
     override val psi: PsiElement?,
     override val reason: String
-) : FirErrorExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirErrorExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirErrorLoop.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirLabel
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirErrorLoop(
     override val psi: PsiElement?
-) : FirLoop, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirLoop, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var block: FirBlock = FirEmptyExpressionBlock()
     override var condition: FirExpression = FirErrorExpressionImpl(psi, "error loop")

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirExpressionStub.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -20,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirExpressionStub(
     override val psi: PsiElement?
-) : FirExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirExpressionWithSmartcastImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.*
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.references.FirReference
@@ -20,7 +21,7 @@ class FirExpressionWithSmartcastImpl(
     override var originalExpression: FirQualifiedAccessExpression,
     override val typeRef: FirTypeRef,
     override val typesFromSmartcast: Collection<ConeKotlinType>
-) : FirExpressionWithSmartcast {
+) : FirPureAbstractElement(), FirExpressionWithSmartcast {
     init {
         assert(originalExpression.typeRef is FirResolvedTypeRef)
     }

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirFunctionCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirFunctionCall
@@ -23,7 +24,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirFunctionCallImpl(
     override val psi: PsiElement?
-) : FirFunctionCall, FirModifiableQualifiedAccess, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirFunctionCall, FirModifiableQualifiedAccess, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var safe: Boolean = false

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirGetClassCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirGetClassCall
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirGetClassCallImpl(
     override val psi: PsiElement?
-) : FirGetClassCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirGetClassCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val arguments: MutableList<FirExpression> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirLambdaArgumentExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirLambdaArgumentExpression
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirLambdaArgumentExpressionImpl(
     override val psi: PsiElement?,
     override var expression: FirExpression
-) : FirLambdaArgumentExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirLambdaArgumentExpression, FirAbstractAnnotatedElement {
     override val typeRef: FirTypeRef get() = expression.typeRef
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val isSpread: Boolean get() = false

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirNamedArgumentExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirNamedArgumentExpression
@@ -24,7 +25,7 @@ class FirNamedArgumentExpressionImpl(
     override var expression: FirExpression,
     override val isSpread: Boolean,
     override val name: Name
-) : FirNamedArgumentExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirNamedArgumentExpression, FirAbstractAnnotatedElement {
     override val typeRef: FirTypeRef get() = expression.typeRef
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirNoReceiverExpression.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -13,7 +14,7 @@ import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.*
 
-object FirNoReceiverExpression : FirExpression {
+object FirNoReceiverExpression : FirPureAbstractElement(), FirExpression {
     override val psi: PsiElement? = null
     override val typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: List<FirAnnotationCall> get() = emptyList()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirOperatorCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirOperation
@@ -24,7 +25,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirOperatorCallImpl(
     override val psi: PsiElement?,
     override val operation: FirOperation
-) : FirOperatorCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirOperatorCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = if (operation in FirOperation.BOOLEANS) {
         FirImplicitBooleanTypeRef(null)
     } else {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirQualifiedAccessExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccessExpression
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirQualifiedAccessExpressionImpl(
     override val psi: PsiElement?
-) : FirQualifiedAccessExpression, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirQualifiedAccessExpression, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var safe: Boolean = false

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirResolvedQualifierImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirResolvedQualifier
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -24,7 +25,7 @@ class FirResolvedQualifierImpl(
     override val psi: PsiElement?,
     override var packageFqName: FqName,
     override var relativeClassFqName: FqName?
-) : FirResolvedQualifier, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirResolvedQualifier, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val classId: ClassId? get() = relativeClassFqName?.let {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirReturnExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirTarget
 import org.jetbrains.kotlin.fir.declarations.FirFunction
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
@@ -24,7 +25,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirReturnExpressionImpl(
     override val psi: PsiElement?,
     override var result: FirExpression
-) : FirReturnExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirReturnExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitNothingTypeRef(psi)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override lateinit var target: FirTarget<FirFunction<*>>

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirSingleExpressionBlock.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirStatement
@@ -19,7 +20,7 @@ import org.jetbrains.kotlin.fir.visitors.transformSingle
 
 class FirSingleExpressionBlock(
     var statement: FirStatement
-) : FirBlock, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirBlock, FirAbstractAnnotatedElement {
     override val psi: PsiElement? get() = statement.psi
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val statements: List<FirStatement> get() = listOf(statement)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirSpreadArgumentExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirSpreadArgumentExpression
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirSpreadArgumentExpressionImpl(
     override val psi: PsiElement?,
     override var expression: FirExpression
-) : FirSpreadArgumentExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirSpreadArgumentExpression, FirAbstractAnnotatedElement {
     override val typeRef: FirTypeRef get() = expression.typeRef
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val isSpread: Boolean get() = true

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirStringConcatenationCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirStringConcatenationCall
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirStringConcatenationCallImpl(
     override val psi: PsiElement?
-) : FirStringConcatenationCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirStringConcatenationCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val arguments: MutableList<FirExpression> = mutableListOf()
     override var typeRef: FirTypeRef = FirImplicitStringTypeRef(psi)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirThisReceiverExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirThisReceiverExpression
@@ -23,7 +24,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirThisReceiverExpressionImpl(
     override val psi: PsiElement?,
     override var calleeReference: FirThisReference
-) : FirThisReceiverExpression, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirThisReceiverExpression, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var safe: Boolean = false

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirThrowExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirThrowExpression
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirThrowExpressionImpl(
     override val psi: PsiElement?,
     override var exception: FirExpression
-) : FirThrowExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirThrowExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitNothingTypeRef(psi)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirTryExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirCatch
@@ -26,7 +27,7 @@ class FirTryExpressionImpl(
     override val psi: PsiElement?,
     override var tryBlock: FirBlock,
     override var finallyBlock: FirBlock?
-) : FirTryExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirTryExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var calleeReference: FirReference = FirStubReference()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirTypeOperatorCallImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirOperation
@@ -24,7 +25,7 @@ class FirTypeOperatorCallImpl(
     override val psi: PsiElement?,
     override val operation: FirOperation,
     override var conversionTypeRef: FirTypeRef
-) : FirTypeOperatorCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirTypeOperatorCall, FirCallWithArgumentList, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val arguments: MutableList<FirExpression> = mutableListOf()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirUnitExpression.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -20,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirUnitExpression(
     override val psi: PsiElement?
-) : FirExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitUnitTypeRef(psi)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirVariableAssignmentImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirOperation
@@ -24,7 +25,7 @@ class FirVariableAssignmentImpl(
     override var safe: Boolean,
     override var rValue: FirExpression,
     override var operation: FirOperation
-) : FirVariableAssignment, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirVariableAssignment, FirModifiableQualifiedAccess, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var explicitReceiver: FirExpression? = null
     override var dispatchReceiver: FirExpression = FirNoReceiverExpression

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirWhenBranchImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirWhenBranch
@@ -20,7 +21,7 @@ class FirWhenBranchImpl(
     override val psi: PsiElement?,
     override var condition: FirExpression,
     override var result: FirBlock
-) : FirWhenBranch {
+) : FirPureAbstractElement(), FirWhenBranch {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         condition.accept(visitor, data)
         result.accept(visitor, data)

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirWhenExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirVariable
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -27,7 +28,7 @@ class FirWhenExpressionImpl(
     override val psi: PsiElement?,
     override var subject: FirExpression?,
     override var subjectVariable: FirVariable<*>?
-) : FirWhenExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirWhenExpression, FirAbstractAnnotatedElement {
     override var typeRef: FirTypeRef = FirImplicitTypeRefImpl(null)
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var calleeReference: FirReference = FirStubReference()

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirWhenSubjectExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.FirWhenSubject
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirWhenSubjectExpression
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirWhenSubjectExpressionImpl(
     override val psi: PsiElement?,
     override val whenSubject: FirWhenSubject
-) : FirWhenSubjectExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirWhenSubjectExpression, FirAbstractAnnotatedElement {
     override val typeRef: FirTypeRef get() = whenSubject.whenExpression.subject!!.typeRef
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirWhileLoopImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirLabel
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirBlock
 import org.jetbrains.kotlin.fir.expressions.FirExpression
@@ -22,7 +23,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirWhileLoopImpl(
     override val psi: PsiElement?,
     override var condition: FirExpression
-) : FirWhileLoop, FirAbstractLoop, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirWhileLoop, FirAbstractLoop, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override var label: FirLabel? = null
     override lateinit var block: FirBlock

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/impl/FirWrappedDelegateExpressionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.expressions.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.expressions.FirWrappedDelegateExpression
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirWrappedDelegateExpressionImpl(
     override val psi: PsiElement?,
     override var expression: FirExpression
-) : FirWrappedDelegateExpression, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirWrappedDelegateExpression, FirAbstractAnnotatedElement {
     override val typeRef: FirTypeRef get() = expression.typeRef
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override lateinit var delegateProvider: FirExpression

compiler/fir/tree/src/org/jetbrains/kotlin/fir/impl/FirLabelImpl.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirLabel
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.visitors.*
 
 /*
@@ -17,7 +18,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirLabelImpl(
     override val psi: PsiElement?,
     override val name: String
-) : FirLabel {
+) : FirPureAbstractElement(), FirLabel {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirLabelImpl {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirBackingFieldReferenceImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirBackingFieldReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirBackingFieldSymbol
@@ -21,7 +22,7 @@ class FirBackingFieldReferenceImpl(
     override val psi: PsiElement?,
     override val candidateSymbol: AbstractFirBasedSymbol<*>?,
     override val resolvedSymbol: FirBackingFieldSymbol
-) : FirBackingFieldReference {
+) : FirPureAbstractElement(), FirBackingFieldReference {
     override val name: Name get() = Name.identifier("\$field")
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirDelegateFieldReferenceImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirDelegateFieldReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirDelegateFieldSymbol
@@ -21,7 +22,7 @@ class FirDelegateFieldReferenceImpl(
     override val psi: PsiElement?,
     override val candidateSymbol: AbstractFirBasedSymbol<*>?,
     override val resolvedSymbol: FirDelegateFieldSymbol<*>
-) : FirDelegateFieldReference {
+) : FirPureAbstractElement(), FirDelegateFieldReference {
     override val name: Name get() = Name.identifier("\$delegate")
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirEmptyControlFlowGraphReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirControlFlowGraphReference
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -14,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-class FirEmptyControlFlowGraphReference : FirControlFlowGraphReference {
+class FirEmptyControlFlowGraphReference : FirPureAbstractElement(), FirControlFlowGraphReference {
     override val psi: PsiElement? = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirErrorNamedReferenceImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirErrorNamedReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.name.Name
@@ -19,7 +20,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirErrorNamedReferenceImpl(
     override val psi: PsiElement?,
     override val errorReason: String
-) : FirErrorNamedReference {
+) : FirPureAbstractElement(), FirErrorNamedReference {
     override val name: Name = Name.special("<$errorReason>")
     override val candidateSymbol: AbstractFirBasedSymbol<*>? get() = null
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirExplicitSuperReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirSuperReference
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -18,7 +19,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirExplicitSuperReference(
     override val psi: PsiElement?,
     override var superTypeRef: FirTypeRef
-) : FirSuperReference {
+) : FirPureAbstractElement(), FirSuperReference {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         superTypeRef.accept(visitor, data)
     }

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirExplicitThisReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirThisReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.fir.visitors.*
@@ -18,7 +19,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirExplicitThisReference(
     override val psi: PsiElement?,
     override val labelName: String?
-) : FirThisReference {
+) : FirPureAbstractElement(), FirThisReference {
     override var boundSymbol: AbstractFirBasedSymbol<*>? = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirImplicitThisReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirThisReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.fir.visitors.*
@@ -17,7 +18,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirImplicitThisReference(
     override val boundSymbol: AbstractFirBasedSymbol<*>?
-) : FirThisReference {
+) : FirPureAbstractElement(), FirThisReference {
     override val psi: PsiElement? = null
     override val labelName: String? get() = null
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirPropertyFromParameterCallableReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirResolvedCallableReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.name.Name
@@ -20,7 +21,7 @@ class FirPropertyFromParameterCallableReference(
     override val psi: PsiElement?,
     override val name: Name,
     override val resolvedSymbol: AbstractFirBasedSymbol<*>
-) : FirResolvedCallableReference {
+) : FirPureAbstractElement(), FirResolvedCallableReference {
     override val candidateSymbol: AbstractFirBasedSymbol<*>? get() = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirResolvedCallableReferenceImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirResolvedCallableReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.name.Name
@@ -20,7 +21,7 @@ class FirResolvedCallableReferenceImpl(
     override val psi: PsiElement?,
     override val name: Name,
     override val resolvedSymbol: AbstractFirBasedSymbol<*>
-) : FirResolvedCallableReference {
+) : FirPureAbstractElement(), FirResolvedCallableReference {
     override val candidateSymbol: AbstractFirBasedSymbol<*>? get() = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirSimpleNamedReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirNamedReference
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.name.Name
@@ -20,7 +21,7 @@ open class FirSimpleNamedReference(
     override val psi: PsiElement?,
     override val name: Name,
     override val candidateSymbol: AbstractFirBasedSymbol<*>?
-) : FirNamedReference {
+) : FirPureAbstractElement(), FirNamedReference {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirSimpleNamedReference {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/references/impl/FirStubReference.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.references.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.references.FirReference
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -14,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-class FirStubReference : FirReference {
+class FirStubReference : FirPureAbstractElement(), FirReference {
     override val psi: PsiElement? get() = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirComputingImplicitTypeRef.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.types.FirImplicitTypeRef
@@ -16,7 +17,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-object FirComputingImplicitTypeRef : FirImplicitTypeRef, FirAbstractAnnotatedElement {
+object FirComputingImplicitTypeRef : FirPureAbstractElement(), FirImplicitTypeRef, FirAbstractAnnotatedElement {
     override val psi: PsiElement? get() = null
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirDelegatedTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.expressions.FirExpression
 import org.jetbrains.kotlin.fir.types.FirDelegatedTypeRef
@@ -20,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirDelegatedTypeRefImpl(
     override var delegate: FirExpression?,
     override var typeRef: FirTypeRef
-) : FirDelegatedTypeRef {
+) : FirPureAbstractElement(), FirDelegatedTypeRef {
     override val psi: PsiElement? get() = typeRef.psi
     override val annotations: List<FirAnnotationCall> get() = typeRef.annotations
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirDynamicTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.types.FirDynamicTypeRef
@@ -19,7 +20,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirDynamicTypeRefImpl(
     override val psi: PsiElement?,
     override val isMarkedNullable: Boolean
-) : FirDynamicTypeRef, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirDynamicTypeRef, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirErrorTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.types.ConeClassErrorType
@@ -21,7 +22,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirErrorTypeRefImpl(
     override val psi: PsiElement?,
     override val reason: String
-) : FirErrorTypeRef, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirErrorTypeRef, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val type: ConeKotlinType = ConeClassErrorType(reason)
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirFunctionTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -23,7 +24,7 @@ class FirFunctionTypeRefImpl(
     override val isMarkedNullable: Boolean,
     override var receiverTypeRef: FirTypeRef?,
     override var returnTypeRef: FirTypeRef
-) : FirFunctionTypeRef, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirFunctionTypeRef, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val valueParameters: MutableList<FirValueParameter> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirImplicitBuiltinTypeRef.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.symbols.StandardClassIds
 import org.jetbrains.kotlin.fir.symbols.impl.ConeClassLikeLookupTagImpl
@@ -22,7 +23,7 @@ sealed class FirImplicitBuiltinTypeRef(
     val id: ClassId,
     typeArguments: Array<out ConeKotlinTypeProjection> = emptyArray(),
     isNullable: Boolean = false
-) : FirResolvedTypeRef {
+) : FirPureAbstractElement(), FirResolvedTypeRef {
     override val annotations: List<FirAnnotationCall>
         get() = emptyList()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirImplicitTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.types.FirImplicitTypeRef
 import org.jetbrains.kotlin.fir.visitors.*
@@ -17,7 +18,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirImplicitTypeRefImpl(
     override val psi: PsiElement?
-) : FirImplicitTypeRef {
+) : FirPureAbstractElement(), FirImplicitTypeRef {
     override val annotations: List<FirAnnotationCall> get() = emptyList()
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirResolvedFunctionTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.declarations.FirValueParameter
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
@@ -25,7 +26,7 @@ class FirResolvedFunctionTypeRefImpl(
     override val isMarkedNullable: Boolean,
     override var receiverTypeRef: FirTypeRef?,
     override var returnTypeRef: FirTypeRef
-) : FirResolvedFunctionTypeRef, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirResolvedFunctionTypeRef, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
     override val valueParameters: MutableList<FirValueParameter> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirResolvedTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.types.ConeKotlinType
@@ -20,7 +21,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 class FirResolvedTypeRefImpl(
     override val psi: PsiElement?,
     override val type: ConeKotlinType
-) : FirResolvedTypeRef, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirResolvedTypeRef, FirAbstractAnnotatedElement {
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirStarProjectionImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.types.FirStarProjection
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -16,7 +17,7 @@ import org.jetbrains.kotlin.fir.visitors.*
 
 class FirStarProjectionImpl(
     override val psi: PsiElement?
-) : FirStarProjection {
+) : FirPureAbstractElement(), FirStarProjection {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}
 
     override fun <D> transformChildren(transformer: FirTransformer<D>, data: D): FirStarProjectionImpl {

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirTypePlaceholderProjection.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.types.FirTypeProjection
 import org.jetbrains.kotlin.fir.visitors.*
 
@@ -14,7 +15,7 @@ import org.jetbrains.kotlin.fir.visitors.*
  * DO NOT MODIFY IT MANUALLY
  */
 
-object FirTypePlaceholderProjection : FirTypeProjection {
+object FirTypePlaceholderProjection : FirPureAbstractElement(), FirTypeProjection {
     override val psi: PsiElement? = null
 
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {}

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirTypeProjectionWithVarianceImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.types.FirTypeProjectionWithVariance
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.types.Variance
@@ -20,7 +21,7 @@ class FirTypeProjectionWithVarianceImpl(
     override val psi: PsiElement?,
     override var typeRef: FirTypeRef,
     override val variance: Variance
-) : FirTypeProjectionWithVariance {
+) : FirPureAbstractElement(), FirTypeProjectionWithVariance {
     override fun <R, D> acceptChildren(visitor: FirVisitor<R, D>, data: D) {
         typeRef.accept(visitor, data)
     }

compiler/fir/tree/src/org/jetbrains/kotlin/fir/types/impl/FirUserTypeRefImpl.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.types.impl
 
 import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationCall
 import org.jetbrains.kotlin.fir.impl.FirAbstractAnnotatedElement
 import org.jetbrains.kotlin.fir.types.FirQualifierPart
@@ -18,7 +19,7 @@ import org.jetbrains.kotlin.fir.visitors.transformInplace
 open class FirUserTypeRefImpl(
     override val psi: PsiElement?,
     override val isMarkedNullable: Boolean
-) : FirUserTypeRef, FirAbstractAnnotatedElement {
+) : FirPureAbstractElement(), FirUserTypeRef, FirAbstractAnnotatedElement {
     override val qualifier: MutableList<FirQualifierPart> = mutableListOf()
     override val annotations: MutableList<FirAnnotationCall> = mutableListOf()
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/visitors/FirTransformerUtil.kt

@@ -6,15 +6,16 @@
 package org.jetbrains.kotlin.fir.visitors
 
 import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.FirPureAbstractElement
 
 fun <T : FirElement, D> T.transformSingle(transformer: FirTransformer<D>, data: D): T {
-    return transform<T, D>(transformer, data).single
+    return (this as FirPureAbstractElement).transform<T, D>(transformer, data).single
 }
 
 fun <T : FirElement, D> MutableList<T>.transformInplace(transformer: FirTransformer<D>, data: D) {
     val iterator = this.listIterator()
     while (iterator.hasNext()) {
-        val next = iterator.next()
+        val next = iterator.next() as FirPureAbstractElement
         val result = next.transform<T, D>(transformer, data)
         if (result.isSingle) {
             iterator.set(result.single)

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/Printer.kt

@@ -169,7 +169,8 @@ fun Implementation.generateCode(generationPath: String) {
 
 fun Implementation.collectImports(): List<String> {
     return element.collectImportsInternal(
-        listOf(element.fullQualifiedName) + usedTypes.mapNotNull { it.fullQualifiedName } + parents.mapNotNull { it.fullQualifiedName },
+        listOf(element.fullQualifiedName) + usedTypes.mapNotNull { it.fullQualifiedName } + parents.mapNotNull { it.fullQualifiedName }
+                + listOfNotNull(pureAbstractElementType.fullQualifiedName?.takeIf { kind != Implementation.Kind.Interface }),
         isImpl = true
     )
 }
@@ -272,7 +273,11 @@ fun PrintWriter.printImplementation(implementation: Implementation) {
             print(")")
         }
 
-        print(" : ${element.typeWithArguments}")
+        print(" : ")
+        if (!isInterface) {
+            print("${pureAbstractElementType.type}(), ")
+        }
+        print(element.typeWithArguments)
         parents.forEach {
             print(", ${it.typeWithArguments}")
         }

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/Types.kt

@@ -59,4 +59,6 @@ val compositeTransformResultType = type("fir.visitors", "CompositeTransformResul
 val abstractFirBasedSymbolType = type("fir.symbols", "AbstractFirBasedSymbol")
 val backingFieldSymbolType = type("fir.symbols.impl", "FirBackingFieldSymbol")
 val delegateFieldSymbolType = type("fir.symbols.impl", "FirDelegateFieldSymbol")
-val classSymbolType = type("fir.symbols.impl", "FirClassSymbol")
+val classSymbolType = type("fir.symbols.impl", "FirClassSymbol")
+
+val pureAbstractElementType = generatedType("FirPureAbstractElement")