IR: introduce abstract class IrDeclarationBase

The main purpose of this class is to improve performance of IR visitors
and transformers. `IrElementVisitor.visitDeclaration` now takes
IrDeclarationBase as a parameter, and therefore the call to `accept`
there is now a virtual class call, instead of an interface call.

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/evaluate/IrConstTransformer.kt

@@ -5,15 +5,18 @@
 
 package org.jetbrains.kotlin.fir.backend.evaluate
 
+import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.declarations.IrAnnotationContainer
+import org.jetbrains.kotlin.ir.declarations.IrField
+import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
+import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
+import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.expressions.impl.IrVarargImpl
 import org.jetbrains.kotlin.ir.interpreter.EvaluationMode
 import org.jetbrains.kotlin.ir.interpreter.IrCompileTimeChecker
 import org.jetbrains.kotlin.ir.interpreter.IrInterpreter
 import org.jetbrains.kotlin.ir.interpreter.toIrConst
-import org.jetbrains.kotlin.ir.IrStatement
-import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
-import org.jetbrains.kotlin.ir.expressions.*
-import org.jetbrains.kotlin.ir.expressions.impl.IrVarargImpl
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 
@@ -51,7 +54,7 @@ class IrConstTransformer(irBuiltIns: IrBuiltIns) : IrElementTransformerVoid() {
         return declaration
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+    override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
         transformAnnotations(declaration)
         return super.visitDeclaration(declaration)
     }
@@ -98,4 +101,4 @@ class IrConstTransformer(irBuiltIns: IrBuiltIns) : IrElementTransformerVoid() {
         if (type.isArray()) return this.convertToConstIfPossible((type as IrSimpleType).arguments.single().typeOrNull!!)
         return this.value.toIrConst(type, this.startOffset, this.endOffset)
     }
-}
+}

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

@@ -312,7 +312,7 @@ class CheckIrElementVisitor(
         expression.symbol.ensureBound(expression)
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration) {
+    override fun visitDeclaration(declaration: IrDeclarationBase) {
         super.visitDeclaration(declaration)
 
         if (declaration is IrOverridableDeclaration<*>) {

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

@@ -98,7 +98,7 @@ object CheckDeclarationParentsVisitor : IrElementVisitor<Unit, IrDeclarationPare
         element.acceptChildren(this, element as? IrDeclarationParent ?: data)
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration, data: IrDeclarationParent?) {
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: IrDeclarationParent?) {
         checkParent(declaration, data)
         super.visitDeclaration(declaration, data)
     }

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

@@ -127,7 +127,7 @@ fun BodyLoweringPass.runOnFilePostfix(irFile: IrFile, withLocalDeclarations: Boo
                 element.acceptChildren(this, data)
             }
 
-            override fun visitDeclaration(declaration: IrDeclaration, data: IrDeclaration?) {
+            override fun visitDeclaration(declaration: IrDeclarationBase, data: IrDeclaration?) {
                 declaration.acceptChildren(this, declaration)
             }
 

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

@@ -78,7 +78,7 @@ private fun IrBody.move(
         return super.visitBlock(expression)
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+    override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
         if (declaration.parent == source)
             declaration.parent = target
         return super.visitDeclaration(declaration)

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

@@ -364,7 +364,7 @@ object SetDeclarationsParentVisitor : IrElementVisitor<Unit, IrDeclarationParent
         }
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration, data: IrDeclarationParent) {
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: IrDeclarationParent) {
         declaration.parent = data
         super.visitDeclaration(declaration, data)
     }

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

@@ -105,7 +105,7 @@ class InlineClassLowering(val context: CommonBackendContext) {
                                 return expression
                             }
 
-                            override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+                            override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
                                 declaration.transformChildrenVoid(this)
                                 if (declaration.parent == irConstructor)
                                     declaration.parent = staticMethod
@@ -142,7 +142,7 @@ class InlineClassLowering(val context: CommonBackendContext) {
                 statements.addAll((functionBody as IrBlockBody).statements)
 
                 transformChildrenVoid(object : IrElementTransformerVoid() {
-                    override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+                    override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
                         declaration.transformChildrenVoid(this)
                         if (declaration.parent == function)
                             declaration.parent = staticMethod

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

@@ -442,7 +442,7 @@ class LocalDeclarationsLowering(
                 return super.visitDeclarationReference(expression)
             }
 
-            override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+            override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
                 if (declaration is IrSymbolOwner && declaration in transformedDeclarations) {
                     TODO()
                 }

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

@@ -91,7 +91,7 @@ class SharedVariablesLowering(val context: BackendContext) : BodyLoweringPass {
                     }
                 }
 
-                override fun visitDeclaration(declaration: IrDeclaration, data: IrDeclarationParent?) {
+                override fun visitDeclaration(declaration: IrDeclarationBase, data: IrDeclarationParent?) {
                     super.visitDeclaration(declaration, declaration as? IrDeclarationParent ?: data)
                 }
 

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

@@ -24,10 +24,7 @@ import org.jetbrains.kotlin.ir.builders.IrBuilderWithScope
 import org.jetbrains.kotlin.ir.builders.createTmpVariable
 import org.jetbrains.kotlin.ir.builders.irCall
 import org.jetbrains.kotlin.ir.builders.irGet
-import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.IrFile
-import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
-import org.jetbrains.kotlin.ir.declarations.IrSymbolDeclaration
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrStringConcatenation
 import org.jetbrains.kotlin.ir.types.IrType
@@ -106,7 +103,7 @@ private class StringConcatenationTransformer(val lower: StringConcatenationLower
         }
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+    override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
         if (declaration !is IrSymbolDeclaration<*>) {
             return super.visitDeclaration(declaration)
         }
@@ -120,4 +117,4 @@ private class StringConcatenationTransformer(val lower: StringConcatenationLower
             return this@with
         }
     }
-}
+}

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/phaser/DumperVerifier.kt

@@ -70,7 +70,7 @@ fun dumpIrElement(actionState: ActionState, data: IrElement, context: Any?): Str
                 element.acceptChildrenVoid(this)
             }
 
-            override fun visitDeclaration(declaration: IrDeclaration) {
+            override fun visitDeclaration(declaration: IrDeclarationBase) {
                 if (declaration is IrDeclarationWithName && FqName(dumpOnlyFqName) == declaration.fqNameWhenAvailable) {
                     dumpText += declaration.dump()
                 } else {

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/Dce.kt

@@ -12,7 +12,10 @@ import org.jetbrains.kotlin.ir.backend.js.utils.*
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
-import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.types.classOrNull
+import org.jetbrains.kotlin.ir.types.classifierOrFail
+import org.jetbrains.kotlin.ir.types.classifierOrNull
+import org.jetbrains.kotlin.ir.types.getClass
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
@@ -184,7 +187,7 @@ fun usefulDeclarations(roots: Iterable<IrDeclaration>, context: JsIrBackendConte
                         // Skip
                     }
 
-                    override fun visitDeclaration(declaration: IrDeclaration) {
+                    override fun visitDeclaration(declaration: IrDeclarationBase) {
                         if (declaration !== it) declaration.enqueue(it, "roots' nested declaration")
 
                         super.visitDeclaration(declaration)
@@ -437,4 +440,4 @@ private fun Collection<IrClass>.filterDescendantsOf(bases: Collection<IrClass>):
     }
 
     return this.filter { overridesAnyBase(it) }
-}
+}

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/ES6AddInternalParametersToConstructorPhase.kt

@@ -88,7 +88,7 @@ class ES6AddInternalParametersToConstructorPhase(val context: JsIrBackendContext
         context.mapping.constructorToInitFunction[constructor] = initFunction
 
         initFunction.transformChildren(object : IrElementTransformerVoid() {
-            override fun visitDeclaration(declaration: IrDeclaration): IrStatement {
+            override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement {
                 declaration.parent = initFunction
                 return declaration
             }

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

@@ -8,19 +8,19 @@ package org.jetbrains.kotlin.ir.backend.js.lower
 import org.jetbrains.kotlin.backend.common.DeclarationTransformer
 import org.jetbrains.kotlin.backend.common.ir.addChild
 import org.jetbrains.kotlin.descriptors.PackageFragmentDescriptor
-import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.utils.getJsModule
 import org.jetbrains.kotlin.ir.backend.js.utils.getJsQualifier
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrFileImpl
 import org.jetbrains.kotlin.ir.symbols.IrFileSymbol
+import org.jetbrains.kotlin.ir.util.IdSignature
 import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
 import org.jetbrains.kotlin.ir.util.isEffectivelyExternal
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
-import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.name.FqName
 
 private val BODILESS_BUILTIN_CLASSES = listOf(
@@ -129,10 +129,10 @@ class MoveBodilessDeclarationsToSeparatePlaceLowering(private val context: JsIrB
                 element.acceptChildrenVoid(this)
             }
 
-            override fun visitDeclaration(declaration: IrDeclaration) {
+            override fun visitDeclaration(declaration: IrDeclarationBase) {
                 context.externalDeclarations.add(declaration)
                 super.visitDeclaration(declaration)
             }
         }, null)
     }
-}
+}

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

@@ -11,13 +11,15 @@ import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.ir.JsIrBuilder
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationParent
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrBranchImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrCatchImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrElseBranchImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrTryImpl
 import org.jetbrains.kotlin.ir.symbols.IrValueSymbol
-import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.types.IrDynamicType
+import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 
 /**
@@ -51,7 +53,7 @@ class MultipleCatchesLowering(private val context: JsIrBackendContext) : BodyLow
     override fun lower(irBody: IrBody, container: IrDeclaration) {
         irBody.transform(object : IrElementTransformer<IrDeclarationParent> {
 
-            override fun visitDeclaration(declaration: IrDeclaration, data: IrDeclarationParent): IrStatement {
+            override fun visitDeclaration(declaration: IrDeclarationBase, data: IrDeclarationParent): IrStatement {
                 val parent = (declaration as? IrDeclarationParent) ?: data
                 return super.visitDeclaration(declaration, parent)
             }
@@ -118,4 +120,4 @@ class MultipleCatchesLowering(private val context: JsIrBackendContext) : BodyLow
 
         }, container as? IrDeclarationParent ?: container.parent)
     }
-}
+}

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

@@ -8,6 +8,7 @@ package org.jetbrains.kotlin.ir.backend.js.lower
 import org.jetbrains.kotlin.backend.common.BodyLoweringPass
 import org.jetbrains.kotlin.backend.common.DeclarationTransformer
 import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.backend.js.JsCommonBackendContext
 import org.jetbrains.kotlin.ir.builders.declarations.addConstructor
 import org.jetbrains.kotlin.ir.declarations.*
@@ -67,7 +68,7 @@ class DelegateToSyntheticPrimaryConstructor(context: JsCommonBackendContext) : B
         if (container is IrConstructor && !container.isPrimary) {
             container.parentAsClass.syntheticPrimaryConstructor?.let { primary ->
                 val initializeTransformer = object : IrElementTransformerVoid() {
-                    override fun visitDeclaration(declaration: IrDeclaration) = declaration // optimize visiting
+                    override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement = declaration // optimize visiting
 
                     override fun visitInstanceInitializerCall(expression: IrInstanceInitializerCall) = expression.run {
                         IrDelegatingConstructorCallImpl(
@@ -83,4 +84,4 @@ class DelegateToSyntheticPrimaryConstructor(context: JsCommonBackendContext) : B
             }
         }
     }
-}
+}

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

@@ -14,6 +14,7 @@ import org.jetbrains.kotlin.ir.backend.js.utils.isPure
 import org.jetbrains.kotlin.ir.declarations.IrClass
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationParent
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrCompositeImpl
 import org.jetbrains.kotlin.ir.expressions.impl.IrTypeOperatorCallImpl
@@ -64,7 +65,7 @@ class TypeOperatorLowering(val context: JsIrBackendContext) : BodyLoweringPass {
 
     override fun lower(irBody: IrBody, container: IrDeclaration) {
         irBody.transformChildren(object : IrElementTransformer<IrDeclarationParent> {
-            override fun visitDeclaration(declaration: IrDeclaration, data: IrDeclarationParent) =
+            override fun visitDeclaration(declaration: IrDeclarationBase, data: IrDeclarationParent) =
                 super.visitDeclaration(declaration, declaration as? IrDeclarationParent ?: data)
 
             override fun visitTypeOperator(expression: IrTypeOperatorCall, data: IrDeclarationParent): IrExpression {
@@ -374,4 +375,4 @@ class TypeOperatorLowering(val context: JsIrBackendContext) : BodyLoweringPass {
             }
         }, container as? IrDeclarationParent ?: container.parent)
     }
-}
+}

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/utils/NameTables.kt

@@ -372,7 +372,7 @@ class NameTables(
             element.acceptChildrenVoid(this)
         }
 
-        override fun visitDeclaration(declaration: IrDeclaration) {
+        override fun visitDeclaration(declaration: IrDeclarationBase) {
             if (declaration is IrDeclarationWithName && declaration is IrSymbolOwner) {
                 table.declareFreshName(declaration, declaration.name.asString())
             }

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/utils/StableNamesCollector.kt

@@ -7,8 +7,8 @@ package org.jetbrains.kotlin.ir.backend.js.utils
 
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrConstructor
-import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationWithName
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.util.isEffectivelyExternal
 import org.jetbrains.kotlin.ir.util.isPropertyAccessor
@@ -30,7 +30,7 @@ class StableNamesCollector : IrElementVisitorVoid {
         element.acceptChildrenVoid(this)
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration) {
+    override fun visitDeclaration(declaration: IrDeclarationBase) {
         super.visitDeclaration(declaration)
 
         if (declaration !is IrDeclarationWithName)

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

@@ -86,7 +86,7 @@ class InventNamesForLocalClasses(private val context: JvmBackendContext) : FileL
             declaration.acceptChildren(this, data.makeLocal())
         }
 
-        override fun visitDeclaration(declaration: IrDeclaration, data: Data) {
+        override fun visitDeclaration(declaration: IrDeclarationBase, data: Data) {
             if (declaration !is IrDeclarationWithName) {
                 declaration.acceptChildren(this, data)
                 return

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

@@ -11,8 +11,8 @@ import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.IrStatement
-import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
@@ -43,7 +43,7 @@ private class JvmArgumentNullabilityAssertionsLowering(context: JvmBackendContex
     override fun visitElement(element: IrElement, data: AssertionScope): IrElement =
         super.visitElement(element, AssertionScope.Enabled)
 
-    override fun visitDeclaration(declaration: IrDeclaration, data: AssertionScope): IrStatement =
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: AssertionScope): IrStatement =
         super.visitDeclaration(declaration, AssertionScope.Enabled)
 
     override fun visitTypeOperator(expression: IrTypeOperatorCall, data: AssertionScope): IrExpression =

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/AnnotationGenerator.kt

@@ -6,10 +6,7 @@
 package org.jetbrains.kotlin.psi2ir.generators
 
 import org.jetbrains.kotlin.ir.IrElement
-import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
-import org.jetbrains.kotlin.ir.declarations.IrField
-import org.jetbrains.kotlin.ir.declarations.IrTypeParametersContainer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 
@@ -21,7 +18,7 @@ class AnnotationGenerator(context: GeneratorContext) : IrElementVisitorVoid {
         element.acceptChildrenVoid(this)
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration) {
+    override fun visitDeclaration(declaration: IrDeclarationBase) {
         if (declaration is IrTypeParametersContainer) {
             typeTranslator.enterScope(declaration)
         }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrAnonymousInitializer.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.ir.symbols.IrAnonymousInitializerSymbol
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
-abstract class IrAnonymousInitializer : IrSymbolDeclaration<IrAnonymousInitializerSymbol> {
+abstract class IrAnonymousInitializer : IrDeclarationBase(), IrSymbolDeclaration<IrAnonymousInitializerSymbol> {
     @ObsoleteDescriptorBasedAPI
     abstract override val descriptor: ClassDescriptor // TODO special descriptor for anonymous initializer blocks
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrClass.kt

@@ -29,7 +29,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 abstract class IrClass :
-    IrSymbolDeclaration<IrClassSymbol>, IrDeclarationWithName, IrDeclarationWithVisibility,
+    IrDeclarationBase(), IrSymbolDeclaration<IrClassSymbol>, IrDeclarationWithName, IrDeclarationWithVisibility,
     IrDeclarationContainer, IrTypeParametersContainer, IrAttributeContainer, IrMetadataSourceOwner {
 
     @ObsoleteDescriptorBasedAPI

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrDeclaration.kt

@@ -43,7 +43,9 @@ interface IrDeclaration : IrStatement, IrMutableAnnotationContainer {
     var parent: IrDeclarationParent
 
     val factory: IrFactory
+}
 
+abstract class IrDeclarationBase : IrDeclaration {
     override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrStatement =
         accept(transformer, data) as IrStatement
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrEnumEntry.kt

@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.ir.symbols.IrEnumEntrySymbol
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
-abstract class IrEnumEntry : IrSymbolDeclaration<IrEnumEntrySymbol>, IrDeclarationWithName {
+abstract class IrEnumEntry : IrDeclarationBase(), IrSymbolDeclaration<IrEnumEntrySymbol>, IrDeclarationWithName {
     @ObsoleteDescriptorBasedAPI
     abstract override val descriptor: ClassDescriptor
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrErrorDeclaration.kt

@@ -19,7 +19,7 @@ package org.jetbrains.kotlin.ir.declarations
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
-abstract class IrErrorDeclaration : IrDeclaration {
+abstract class IrErrorDeclaration : IrDeclarationBase() {
     override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
         visitor.visitErrorDeclaration(this, data)
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrField.kt

@@ -15,6 +15,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 abstract class IrField :
+    IrDeclarationBase(),
     IrSymbolDeclaration<IrFieldSymbol>,
     IrDeclarationWithName, IrDeclarationWithVisibility, IrDeclarationParent, IrMetadataSourceOwner {
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrFunction.kt

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 abstract class IrFunction :
+    IrDeclarationBase(),
     IrDeclarationWithName, IrDeclarationWithVisibility, IrTypeParametersContainer, IrSymbolOwner, IrDeclarationParent, IrReturnTarget,
     IrMetadataSourceOwner {
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrLocalDelegatedProperty.kt

@@ -24,6 +24,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 abstract class IrLocalDelegatedProperty :
+    IrDeclarationBase(),
     IrDeclarationWithName,
     IrSymbolOwner,
     IrMetadataSourceOwner {

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrProperty.kt

@@ -22,7 +22,7 @@ import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
-abstract class IrProperty : IrOverridableMember, IrMetadataSourceOwner {
+abstract class IrProperty : IrDeclarationBase(), IrOverridableMember, IrMetadataSourceOwner {
     @ObsoleteDescriptorBasedAPI
     abstract override val descriptor: PropertyDescriptor
     abstract override val symbol: IrPropertySymbol

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrScript.kt

@@ -10,7 +10,8 @@ import org.jetbrains.kotlin.ir.symbols.IrScriptSymbol
 
 //TODO: make IrScript as IrPackageFragment, because script is used as a file, not as a class
 //NOTE: declarations and statements stored separately
-abstract class IrScript : IrSymbolDeclaration<IrScriptSymbol>, IrDeclarationContainer, IrDeclarationWithName, IrDeclarationParent {
+abstract class IrScript :
+    IrDeclarationBase(), IrSymbolDeclaration<IrScriptSymbol>, IrDeclarationContainer, IrDeclarationWithName, IrDeclarationParent {
     abstract val statements: MutableList<IrStatement>
 
     // NOTE: is the result of the FE conversion, because there script interpreted as a class and has receiver

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrTypeAlias.kt

@@ -14,6 +14,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 abstract class IrTypeAlias :
+    IrDeclarationBase(),
     IrSymbolDeclaration<IrTypeAliasSymbol>,
     IrDeclarationWithName,
     IrDeclarationWithVisibility,

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrTypeParameter.kt

@@ -24,7 +24,7 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.types.Variance
 
-abstract class IrTypeParameter : IrSymbolDeclaration<IrTypeParameterSymbol>, IrDeclarationWithName {
+abstract class IrTypeParameter : IrDeclarationBase(), IrSymbolDeclaration<IrTypeParameterSymbol>, IrDeclarationWithName {
     @ObsoleteDescriptorBasedAPI
     abstract override val descriptor: TypeParameterDescriptor
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/IrValueDeclaration.kt

@@ -10,7 +10,7 @@ import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrValueSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 
-abstract class IrValueDeclaration : IrDeclarationWithName, IrSymbolOwner {
+abstract class IrValueDeclaration : IrDeclarationBase(), IrDeclarationWithName, IrSymbolOwner {
     @ObsoleteDescriptorBasedAPI
     abstract override val descriptor: ValueDescriptor
 

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

@@ -109,7 +109,7 @@ open class DeepCopyIrTreeWithSymbols(
             declaration.transformDeclarationsTo(this)
         }
 
-    override fun visitDeclaration(declaration: IrDeclaration): IrStatement =
+    override fun visitDeclaration(declaration: IrDeclarationBase): IrStatement =
         throw IllegalArgumentException("Unsupported declaration type: $declaration")
 
     override fun visitScript(declaration: IrScript): IrStatement {

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

@@ -9,7 +9,7 @@ import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationParent
 import org.jetbrains.kotlin.ir.declarations.IrPackageFragment
-import org.jetbrains.kotlin.ir.declarations.IrProperty
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
@@ -39,7 +39,7 @@ class PatchDeclarationParentsVisitor() : IrElementVisitorVoid {
         declarationParentsStack.pop()
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration) {
+    override fun visitDeclaration(declaration: IrDeclarationBase) {
         patchParent(declaration)
 
         if (declaration is IrDeclarationParent) {
@@ -56,4 +56,4 @@ class PatchDeclarationParentsVisitor() : IrElementVisitorVoid {
     private fun patchParent(declaration: IrDeclaration) {
         declaration.parent = declarationParentsStack.peekFirst()
     }
-}
+}

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

@@ -19,8 +19,8 @@ package org.jetbrains.kotlin.ir.util
 import com.intellij.openapi.util.text.StringUtil
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.ReceiverParameterDescriptor
-import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.symbols.IrClassifierSymbol
@@ -340,7 +340,7 @@ class RenderIrElementVisitor(private val normalizeNames: Boolean = false) : IrEl
     override fun visitElement(element: IrElement, data: Nothing?): String =
         "?ELEMENT? ${element::class.java.simpleName} $element"
 
-    override fun visitDeclaration(declaration: IrDeclaration, data: Nothing?): String =
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: Nothing?): String =
         "?DECLARATION? ${declaration::class.java.simpleName} $declaration"
 
     override fun visitModuleFragment(declaration: IrModuleFragment, data: Nothing?): String =

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementTransformer.kt

@@ -34,7 +34,7 @@ interface IrElementTransformer<in D> : IrElementVisitor<IrElement, D> {
     override fun visitExternalPackageFragment(declaration: IrExternalPackageFragment, data: D): IrExternalPackageFragment =
         declaration.also { it.transformChildren(this, data) }
 
-    override fun visitDeclaration(declaration: IrDeclaration, data: D): IrStatement =
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: D): IrStatement =
         declaration.also { it.transformChildren(this, data) }
 
     override fun visitScript(declaration: IrScript, data: D) = visitDeclaration(declaration, data)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementTransformerVoid.kt

@@ -43,8 +43,8 @@ abstract class IrElementTransformerVoid : IrElementTransformer<Nothing?> {
     final override fun visitExternalPackageFragment(declaration: IrExternalPackageFragment, data: Nothing?): IrExternalPackageFragment =
         visitExternalPackageFragment(declaration)
 
-    open fun visitDeclaration(declaration: IrDeclaration): IrStatement = declaration.transformChildren()
+    open fun visitDeclaration(declaration: IrDeclarationBase): IrStatement = declaration.transformChildren()
-    final override fun visitDeclaration(declaration: IrDeclaration, data: Nothing?): IrStatement = visitDeclaration(declaration)
+    final override fun visitDeclaration(declaration: IrDeclarationBase, data: Nothing?): IrStatement = visitDeclaration(declaration)
 
     open fun visitScript(declaration: IrScript) = visitDeclaration(declaration)
     final override fun visitScript(declaration: IrScript, data: Nothing?) = visitScript(declaration)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementVisitor.kt

@@ -28,7 +28,7 @@ interface IrElementVisitor<out R, in D> {
     fun visitExternalPackageFragment(declaration: IrExternalPackageFragment, data: D) = visitPackageFragment(declaration, data)
     fun visitScript(declaration: IrScript, data: D) = visitDeclaration(declaration, data)
 
-    fun visitDeclaration(declaration: IrDeclaration, data: D) = visitElement(declaration, data)
+    fun visitDeclaration(declaration: IrDeclarationBase, data: D) = visitElement(declaration, data)
     fun visitClass(declaration: IrClass, data: D) = visitDeclaration(declaration, data)
     fun visitFunction(declaration: IrFunction, data: D) = visitDeclaration(declaration, data)
     fun visitSimpleFunction(declaration: IrSimpleFunction, data: D) = visitFunction(declaration, data)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementVisitorVoid.kt

@@ -37,8 +37,8 @@ interface IrElementVisitorVoid : IrElementVisitor<Unit, Nothing?> {
     fun visitFile(declaration: IrFile) = visitPackageFragment(declaration)
     override fun visitFile(declaration: IrFile, data: Nothing?) = visitFile(declaration)
 
-    fun visitDeclaration(declaration: IrDeclaration) = visitElement(declaration)
+    fun visitDeclaration(declaration: IrDeclarationBase) = visitElement(declaration)
-    override fun visitDeclaration(declaration: IrDeclaration, data: Nothing?) = visitDeclaration(declaration)
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: Nothing?) = visitDeclaration(declaration)
 
     fun visitClass(declaration: IrClass) = visitDeclaration(declaration)
     override fun visitClass(declaration: IrClass, data: Nothing?) = visitClass(declaration)

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

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.backend.common.serialization.mangle
 
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationBase
 import org.jetbrains.kotlin.ir.util.KotlinMangler
 import org.jetbrains.kotlin.ir.util.render
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
@@ -47,8 +48,7 @@ class ManglerChecker(vararg _manglers: KotlinMangler<IrDeclaration>) : IrElement
         return r
     }
 
-    override fun visitDeclaration(declaration: IrDeclaration) {
+    override fun visitDeclaration(declaration: IrDeclarationBase) {
-
         val exported = manglers.checkAllEqual(false, { isExportCheck(declaration) }) { m1, r1, m2, r2 ->
             error("${declaration.render()}\n ${m1.manglerName}: $r1\n ${m2.manglerName}: $r2\n")
         }
@@ -69,4 +69,4 @@ class ManglerChecker(vararg _manglers: KotlinMangler<IrDeclaration>) : IrElement
 
         declaration.acceptChildrenVoid(this)
     }
-}
+}

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

@@ -39,7 +39,7 @@ abstract class IrExportCheckerVisitor : IrElementVisitor<Boolean, Nothing?>, Kot
 
     override fun visitElement(element: IrElement, data: Nothing?): Boolean = error("Should bot reach here ${element.render()}")
 
-    override fun visitDeclaration(declaration: IrDeclaration, data: Nothing?) = declaration.run { isExported(annotations, null) }
+    override fun visitDeclaration(declaration: IrDeclarationBase, data: Nothing?) = declaration.run { isExported(annotations, null) }
 
     override fun visitAnonymousInitializer(declaration: IrAnonymousInitializer, data: Nothing?) = false
     override fun visitValueParameter(declaration: IrValueParameter, data: Nothing?) = false

compiler/tests-common/tests/org/jetbrains/kotlin/ir/AbstractIrTextTestCase.kt

@@ -181,7 +181,7 @@ abstract class AbstractIrTextTestCase : AbstractIrGeneratorTestCase() {
         }
 
         @OptIn(ObsoleteDescriptorBasedAPI::class)
-        override fun visitDeclaration(declaration: IrDeclaration) {
+        override fun visitDeclaration(declaration: IrDeclarationBase) {
             if (declaration is IrSymbolOwner) {
                 declaration.symbol.checkBinding("decl", declaration)