IR: pull up common accept/transform implementations to interfaces

To avoid duplicating them among the main, persisting, lazy, and
fir2ir-lazy implementations.

Also reformat a bit, and avoid storing descriptor in a field in some
places.

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/lazy/Fir2IrLazyClass.kt

@@ -21,10 +21,6 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.lazy.lazyVar
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
-import org.jetbrains.kotlin.ir.util.transform
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class Fir2IrLazyClass(
@@ -192,19 +188,4 @@ class Fir2IrLazyClass(
             else -> false
         }
     }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitClass(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        thisReceiver?.accept(visitor, data)
-        typeParameters.forEach { it.accept(visitor, data) }
-        declarations.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        thisReceiver = thisReceiver?.transform(transformer, data)
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-        declarations.transform { it.transform(transformer, data) }
-    }
 }

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/lazy/Fir2IrLazyConstructor.kt

@@ -18,8 +18,6 @@ import org.jetbrains.kotlin.ir.declarations.lazy.lazyVar
 import org.jetbrains.kotlin.ir.expressions.IrBody
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.parentClassOrNull
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
@@ -114,24 +112,4 @@ class Fir2IrLazyConstructor(
     override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
         return visitor.visitConstructor(this, data)
     }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        typeParameters.forEach { it.accept(visitor, data) }
-
-        dispatchReceiverParameter?.accept(visitor, data)
-        extensionReceiverParameter?.accept(visitor, data)
-        valueParameters.forEach { it.accept(visitor, data) }
-
-        body?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-
-        dispatchReceiverParameter = dispatchReceiverParameter?.transform(transformer, data)
-        extensionReceiverParameter = extensionReceiverParameter?.transform(transformer, data)
-        valueParameters = valueParameters.transformIfNeeded(transformer, data)
-
-        body = body?.transform(transformer, data)
-    }
 }

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/lazy/Fir2IrLazyProperty.kt

@@ -21,8 +21,6 @@ import org.jetbrains.kotlin.ir.declarations.lazy.lazyVar
 import org.jetbrains.kotlin.ir.types.IrErrorType
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.isInterface
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class Fir2IrLazyProperty(
@@ -152,20 +150,4 @@ class Fir2IrLazyProperty(
     override var metadata: MetadataSource?
         get() = null
         set(_) = error("We should never need to store metadata of external declarations.")
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitProperty(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        backingField?.accept(visitor, data)
-        getter?.accept(visitor, data)
-        setter?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        backingField = backingField?.transform(transformer, data) as? IrField
-        getter = getter?.run { transform(transformer, data) as IrSimpleFunction }
-        setter = setter?.run { transform(transformer, data) as IrSimpleFunction }
-    }
 }

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/lazy/Fir2IrLazySimpleFunction.kt

@@ -21,9 +21,6 @@ import org.jetbrains.kotlin.ir.expressions.IrBody
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class Fir2IrLazySimpleFunction(
@@ -141,28 +138,4 @@ class Fir2IrLazySimpleFunction(
     override var metadata: MetadataSource?
         get() = null
         set(_) = error("We should never need to store metadata of external declarations.")
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitSimpleFunction(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        typeParameters.forEach { it.accept(visitor, data) }
-
-        dispatchReceiverParameter?.accept(visitor, data)
-        extensionReceiverParameter?.accept(visitor, data)
-        valueParameters.forEach { it.accept(visitor, data) }
-
-        body?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-
-        dispatchReceiverParameter = dispatchReceiverParameter?.transform(transformer, data)
-        extensionReceiverParameter = extensionReceiverParameter?.transform(transformer, data)
-        valueParameters = valueParameters.transformIfNeeded(transformer, data)
-
-        body = body?.transform(transformer, data)
-    }
 }

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

@@ -20,6 +20,8 @@ import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.expressions.IrBlockBody
 import org.jetbrains.kotlin.ir.symbols.IrAnonymousInitializerSymbol
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrAnonymousInitializer : IrSymbolDeclaration<IrAnonymousInitializerSymbol> {
     @ObsoleteDescriptorBasedAPI
@@ -27,5 +29,15 @@ interface IrAnonymousInitializer : IrSymbolDeclaration<IrAnonymousInitializerSym
     val isStatic: Boolean
 
     var body: IrBlockBody
-}
 
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitAnonymousInitializer(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        body.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        body = body.transform(transformer, data) as IrBlockBody
+    }
+}

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

@@ -23,6 +23,10 @@ import org.jetbrains.kotlin.descriptors.SourceElement
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.util.transform
+import org.jetbrains.kotlin.ir.util.transformIfNeeded
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrClass :
     IrSymbolDeclaration<IrClassSymbol>, IrDeclarationWithName, IrDeclarationWithVisibility,
@@ -46,6 +50,21 @@ interface IrClass :
     var superTypes: List<IrType>
 
     var thisReceiver: IrValueParameter?
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitClass(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        thisReceiver?.accept(visitor, data)
+        typeParameters.forEach { it.accept(visitor, data) }
+        declarations.forEach { it.accept(visitor, data) }
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        thisReceiver = thisReceiver?.transform(transformer, data)
+        typeParameters = typeParameters.transformIfNeeded(transformer, data)
+        declarations.transform { it.transform(transformer, data) }
+    }
 }
 
 fun IrClass.addMember(member: IrDeclaration) {

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

@@ -19,10 +19,14 @@ package org.jetbrains.kotlin.ir.declarations
 import org.jetbrains.kotlin.descriptors.ClassConstructorDescriptor
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrConstructor : IrFunction, IrSymbolDeclaration<IrConstructorSymbol> {
     @ObsoleteDescriptorBasedAPI
     override val descriptor: ClassConstructorDescriptor
 
     val isPrimary: Boolean
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitConstructor(this, data)
 }

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

@@ -20,6 +20,8 @@ import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrEnumEntrySymbol
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrEnumEntry : IrSymbolDeclaration<IrEnumEntrySymbol>, IrDeclarationWithName {
     @ObsoleteDescriptorBasedAPI
@@ -27,5 +29,17 @@ interface IrEnumEntry : IrSymbolDeclaration<IrEnumEntrySymbol>, IrDeclarationWit
 
     var correspondingClass: IrClass?
     var initializerExpression: IrExpressionBody?
-}
 
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitEnumEntry(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        initializerExpression?.accept(visitor, data)
+        correspondingClass?.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        initializerExpression = initializerExpression?.transform(transformer, data)
+        correspondingClass = correspondingClass?.transform(transformer, data) as? IrClass
+    }
+}

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

@@ -16,5 +16,18 @@
 
 package org.jetbrains.kotlin.ir.declarations
 
-interface IrErrorDeclaration : IrDeclaration
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
+interface IrErrorDeclaration : IrDeclaration {
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitErrorDeclaration(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        // no children
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        // no children
+    }
+}

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

@@ -11,6 +11,8 @@ import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrField :
     IrSymbolDeclaration<IrFieldSymbol>,
@@ -27,4 +29,15 @@ interface IrField :
     var initializer: IrExpressionBody?
 
     var correspondingPropertySymbol: IrPropertySymbol?
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitField(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        initializer?.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        initializer = initializer?.transform(transformer, data)
+    }
 }

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

@@ -23,6 +23,9 @@ import org.jetbrains.kotlin.ir.expressions.IrBody
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.util.transformIfNeeded
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrFunction :
     IrDeclarationWithName, IrDeclarationWithVisibility, IrTypeParametersContainer, IrSymbolOwner, IrDeclarationParent, IrReturnTarget,
@@ -43,6 +46,26 @@ interface IrFunction :
     var valueParameters: List<IrValueParameter>
 
     var body: IrBody?
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        typeParameters.forEach { it.accept(visitor, data) }
+
+        dispatchReceiverParameter?.accept(visitor, data)
+        extensionReceiverParameter?.accept(visitor, data)
+        valueParameters.forEach { it.accept(visitor, data) }
+
+        body?.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        typeParameters = typeParameters.transformIfNeeded(transformer, data)
+
+        dispatchReceiverParameter = dispatchReceiverParameter?.transform(transformer, data)
+        extensionReceiverParameter = extensionReceiverParameter?.transform(transformer, data)
+        valueParameters = valueParameters.transformIfNeeded(transformer, data)
+
+        body = body?.transform(transformer, data)
+    }
 }
 
 @ObsoleteDescriptorBasedAPI

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

@@ -20,6 +20,8 @@ import org.jetbrains.kotlin.descriptors.VariableDescriptorWithAccessors
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrLocalDelegatedPropertySymbol
 import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrLocalDelegatedProperty :
     IrDeclarationWithName,
@@ -36,4 +38,19 @@ interface IrLocalDelegatedProperty :
     var delegate: IrVariable
     var getter: IrFunction
     var setter: IrFunction?
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitLocalDelegatedProperty(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        delegate.accept(visitor, data)
+        getter.accept(visitor, data)
+        setter?.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        delegate = delegate.transform(transformer, data) as IrVariable
+        getter = getter.transform(transformer, data) as IrFunction
+        setter = setter?.transform(transformer, data) as? IrFunction
+    }
 }

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

@@ -19,6 +19,8 @@ package org.jetbrains.kotlin.ir.declarations
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrProperty : IrOverridableMember, IrMetadataSourceOwner {
     @ObsoleteDescriptorBasedAPI
@@ -36,4 +38,19 @@ interface IrProperty : IrOverridableMember, IrMetadataSourceOwner {
     var backingField: IrField?
     var getter: IrSimpleFunction?
     var setter: IrSimpleFunction?
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitProperty(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        backingField?.accept(visitor, data)
+        getter?.accept(visitor, data)
+        setter?.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        backingField = backingField?.transform(transformer, data) as? IrField
+        getter = getter?.run { transform(transformer, data) as IrSimpleFunction }
+        setter = setter?.run { transform(transformer, data) as IrSimpleFunction }
+    }
 }

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

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.ir.declarations
 
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrSimpleFunction :
     IrFunction,
@@ -22,6 +23,9 @@ interface IrSimpleFunction :
     val isInfix: Boolean
 
     var correspondingPropertySymbol: IrPropertySymbol?
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitSimpleFunction(this, data)
 }
 
 val IrFunction.isPropertyAccessor: Boolean

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

@@ -9,6 +9,9 @@ import org.jetbrains.kotlin.descriptors.TypeAliasDescriptor
 import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrTypeAliasSymbol
 import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.util.transformIfNeeded
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrTypeAlias :
     IrSymbolDeclaration<IrTypeAliasSymbol>,
@@ -21,4 +24,15 @@ interface IrTypeAlias :
 
     val isActual: Boolean
     val expandedType: IrType
-}
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitTypeAlias(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        typeParameters.forEach { it.accept(visitor, data) }
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        typeParameters = typeParameters.transformIfNeeded(transformer, data)
+    }
+}

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

@@ -21,6 +21,7 @@ import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.types.Variance
 
 interface IrTypeParameter : IrSymbolDeclaration<IrTypeParameterSymbol>, IrDeclarationWithName {
@@ -32,5 +33,17 @@ interface IrTypeParameter : IrSymbolDeclaration<IrTypeParameterSymbol>, IrDeclar
     val isReified: Boolean
     val superTypes: MutableList<IrType>
 
-    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrTypeParameter
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-}
+        visitor.visitTypeParameter(this, data)
+
+    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrTypeParameter =
+        transformer.visitTypeParameter(this, data) as IrTypeParameter
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        // no children
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        // no children
+    }
+}

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

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrValueParameterSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrValueParameter : IrValueDeclaration, IrSymbolDeclaration<IrValueParameterSymbol> {
     @ObsoleteDescriptorBasedAPI
@@ -34,5 +35,17 @@ interface IrValueParameter : IrValueDeclaration, IrSymbolDeclaration<IrValuePara
 
     var defaultValue: IrExpressionBody?
 
-    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrValueParameter
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-}
+        visitor.visitValueParameter(this, data)
+
+    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrValueParameter =
+        transformer.visitValueParameter(this, data) as IrValueParameter
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        defaultValue?.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        defaultValue = defaultValue?.transform(transformer, data)
+    }
+}

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

@@ -23,8 +23,6 @@ import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.AnonymousInitializerCarrier
 import org.jetbrains.kotlin.ir.expressions.IrBlockBody
 import org.jetbrains.kotlin.ir.symbols.IrAnonymousInitializerSymbol
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 class IrAnonymousInitializerImpl(
     startOffset: Int,
@@ -41,7 +39,8 @@ class IrAnonymousInitializerImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: ClassDescriptor get() = symbol.descriptor
+    override val descriptor: ClassDescriptor
+        get() = symbol.descriptor
 
     override var bodyField: IrBlockBody? = null
 
@@ -55,16 +54,4 @@ class IrAnonymousInitializerImpl(
                 setCarrier().bodyField = v
             }
         }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitAnonymousInitializer(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        body.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        body = body.transform(transformer, data) as IrBlockBody
-    }
 }

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

@@ -22,10 +22,6 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.ClassCarrier
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.util.transform
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 import java.util.*
 import kotlin.collections.ArrayList
@@ -57,7 +53,8 @@ class IrClassImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: ClassDescriptor get() = symbol.descriptor
+    override val descriptor: ClassDescriptor
+        get() = symbol.descriptor
 
     override var visibilityField: Visibility = visibility
 
@@ -144,19 +141,4 @@ class IrClassImpl(
                 setCarrier().attributeOwnerIdField = v
             }
         }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitClass(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        thisReceiver?.accept(visitor, data)
-        typeParameters.forEach { it.accept(visitor, data) }
-        declarations.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        thisReceiver = thisReceiver?.transform(transformer, data)
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-        declarations.transform { it.transform(transformer, data) }
-    }
 }

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

@@ -24,7 +24,6 @@ import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.ConstructorCarrier
 import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class IrConstructorImpl(
@@ -54,8 +53,6 @@ class IrConstructorImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: ClassConstructorDescriptor get() = symbol.descriptor
+    override val descriptor: ClassConstructorDescriptor
-
+        get() = symbol.descriptor
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitConstructor(this, data)
 }

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

@@ -24,8 +24,6 @@ import org.jetbrains.kotlin.ir.declarations.IrEnumEntry
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.EnumEntryCarrier
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrEnumEntrySymbol
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class IrEnumEntryImpl(
@@ -43,7 +41,8 @@ class IrEnumEntryImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: ClassDescriptor get() = symbol.descriptor
+    override val descriptor: ClassDescriptor
+        get() = symbol.descriptor
 
     override var correspondingClassField: IrClass? = null
 
@@ -67,18 +66,4 @@ class IrEnumEntryImpl(
                 setCarrier().initializerExpressionField = v
             }
         }
-
+}
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitEnumEntry(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        initializerExpression?.accept(visitor, data)
-        correspondingClass?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        initializerExpression = initializerExpression?.transform(transformer, data)
-        correspondingClass = correspondingClass?.transform(transformer, data) as? IrClass
-    }
-}

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

@@ -21,25 +21,10 @@ import org.jetbrains.kotlin.ir.ObsoleteDescriptorBasedAPI
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
 import org.jetbrains.kotlin.ir.declarations.IrErrorDeclaration
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.ErrorCarrier
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
 class IrErrorDeclarationImpl(
     startOffset: Int,
     endOffset: Int,
     override val descriptor: DeclarationDescriptor
-) : IrDeclarationBase<ErrorCarrier>(startOffset, endOffset, IrDeclarationOrigin.DEFINED), IrErrorDeclaration, ErrorCarrier {
+) : IrDeclarationBase<ErrorCarrier>(startOffset, endOffset, IrDeclarationOrigin.DEFINED), IrErrorDeclaration, ErrorCarrier
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitErrorDeclaration(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        // no children
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        // no children
-    }
-}

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

@@ -27,8 +27,6 @@ import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class IrFieldImpl(
@@ -51,7 +49,8 @@ class IrFieldImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: PropertyDescriptor = symbol.descriptor
+    override val descriptor: PropertyDescriptor
+        get() = symbol.descriptor
 
     override var initializerField: IrExpressionBody? = null
 
@@ -85,16 +84,4 @@ class IrFieldImpl(
                 setCarrier().metadataField = v
             }
         }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitField(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        initializer?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        initializer = initializer?.transform(transformer, data)
-    }
 }

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

@@ -22,9 +22,6 @@ import org.jetbrains.kotlin.ir.declarations.impl.carriers.FunctionBaseCarrier
 import org.jetbrains.kotlin.ir.expressions.IrBody
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.impl.IrUninitializedType
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 abstract class IrFunctionBase<T : FunctionBaseCarrier>(
@@ -51,6 +48,7 @@ abstract class IrFunctionBase<T : FunctionBaseCarrier>(
                 setCarrier().returnTypeFieldField = v
             }
         }
+
     @Suppress("DEPRECATION")
     final override var returnType: IrType
         get() = returnTypeField.let {
@@ -132,24 +130,4 @@ abstract class IrFunctionBase<T : FunctionBaseCarrier>(
                 setCarrier().visibilityField = v
             }
         }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        typeParameters.forEach { it.accept(visitor, data) }
-
-        dispatchReceiverParameter?.accept(visitor, data)
-        extensionReceiverParameter?.accept(visitor, data)
-        valueParameters.forEach { it.accept(visitor, data) }
-
-        body?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-
-        dispatchReceiverParameter = dispatchReceiverParameter?.transform(transformer, data)
-        extensionReceiverParameter = extensionReceiverParameter?.transform(transformer, data)
-        valueParameters = valueParameters.transformIfNeeded(transformer, data)
-
-        body = body?.transform(transformer, data)
-    }
 }

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

@@ -18,7 +18,6 @@ import org.jetbrains.kotlin.ir.descriptors.WrappedSimpleFunctionDescriptor
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 abstract class IrFunctionCommonImpl(
@@ -53,6 +52,7 @@ abstract class IrFunctionCommonImpl(
             }
         }
 
+    @Suppress("LeakingThis")
     override var attributeOwnerIdField: IrAttributeContainer = this
 
     override var attributeOwnerId: IrAttributeContainer
@@ -72,9 +72,6 @@ abstract class IrFunctionCommonImpl(
                 setCarrier().correspondingPropertySymbolField = v
             }
         }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitSimpleFunction(this, data)
 }
 
 class IrFunctionImpl(
@@ -105,9 +102,6 @@ class IrFunctionImpl(
     init {
         symbol.bind(this)
     }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitSimpleFunction(this, data)
 }
 
 class IrFakeOverrideFunctionImpl(

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

@@ -22,8 +22,6 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.LocalDelegatedPropertyCarrier
 import org.jetbrains.kotlin.ir.symbols.IrLocalDelegatedPropertySymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 // TODO make not persistent
@@ -87,19 +85,4 @@ class IrLocalDelegatedPropertyImpl(
                 setCarrier().metadataField = v
             }
         }
-
+}
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitLocalDelegatedProperty(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        delegate.accept(visitor, data)
-        getter.accept(visitor, data)
-        setter?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        delegate = delegate.transform(transformer, data) as IrVariable
-        getter = getter.transform(transformer, data) as IrFunction
-        setter = setter?.transform(transformer, data) as? IrFunction
-    }
-}

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

@@ -24,8 +24,6 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.PropertyCarrier
 import org.jetbrains.kotlin.ir.descriptors.WrappedPropertyDescriptor
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 abstract class IrPropertyCommonImpl(
@@ -77,17 +75,6 @@ abstract class IrPropertyCommonImpl(
             }
         }
 
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitProperty(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        backingField?.accept(visitor, data)
-        getter?.accept(visitor, data)
-        setter?.accept(visitor, data)
-    }
-
     override var metadataField: MetadataSource? = null
 
     override var metadata: MetadataSource?
@@ -97,12 +84,6 @@ abstract class IrPropertyCommonImpl(
                 setCarrier().metadataField = v
             }
         }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        backingField = backingField?.transform(transformer, data) as? IrField
-        getter = getter?.run { transform(transformer, data) as IrSimpleFunction }
-        setter = setter?.run { transform(transformer, data) as IrSimpleFunction }
-    }
 }
 
 class IrPropertyImpl(
@@ -128,7 +109,8 @@ class IrPropertyImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: PropertyDescriptor = symbol.descriptor
+    override val descriptor: PropertyDescriptor
+        get() = symbol.descriptor
 }
 
 class IrFakeOverridePropertyImpl(

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

@@ -14,9 +14,6 @@ import org.jetbrains.kotlin.ir.declarations.IrTypeParameter
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.TypeAliasCarrier
 import org.jetbrains.kotlin.ir.symbols.IrTypeAliasSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class IrTypeAliasImpl(
@@ -50,15 +47,4 @@ class IrTypeAliasImpl(
                 setCarrier().typeParametersField = v
             }
         }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitTypeAlias(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        typeParameters.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-    }
 }

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

@@ -23,8 +23,6 @@ import org.jetbrains.kotlin.ir.declarations.IrTypeParameter
 import org.jetbrains.kotlin.ir.declarations.impl.carriers.TypeParameterCarrier
 import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.Variance
 import org.jetbrains.kotlin.utils.SmartList
@@ -48,21 +46,8 @@ class IrTypeParameterImpl(
     }
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: TypeParameterDescriptor get() = symbol.descriptor
+    override val descriptor: TypeParameterDescriptor
+        get() = symbol.descriptor
 
     override val superTypes: MutableList<IrType> = SmartList()
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitTypeParameter(this, data)
-
-    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrTypeParameter =
-        transformer.visitTypeParameter(this, data) as IrTypeParameter
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        // no children
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        // no children
-    }
 }

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

@@ -24,8 +24,6 @@ import org.jetbrains.kotlin.ir.declarations.impl.carriers.ValueParameterCarrier
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrValueParameterSymbol
 import org.jetbrains.kotlin.ir.types.IrType
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 class IrValueParameterImpl(
@@ -45,7 +43,8 @@ class IrValueParameterImpl(
     ValueParameterCarrier {
 
     @ObsoleteDescriptorBasedAPI
-    override val descriptor: ParameterDescriptor = symbol.descriptor
+    override val descriptor: ParameterDescriptor
+        get() = symbol.descriptor
 
     init {
         symbol.bind(this)
@@ -63,18 +62,4 @@ class IrValueParameterImpl(
                 setCarrier().defaultValueField = v
             }
         }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitValueParameter(this, data)
-
-    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrValueParameter =
-        transformer.visitValueParameter(this, data) as IrValueParameter
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        defaultValue?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        defaultValue = defaultValue?.transform(transformer, data)
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyClass.kt

@@ -12,10 +12,6 @@ import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.util.transform
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.metadata.ProtoBuf
 import org.jetbrains.kotlin.metadata.deserialization.NameResolver
 import org.jetbrains.kotlin.name.Name
@@ -94,19 +90,4 @@ class IrLazyClass(
     override var metadata: MetadataSource?
         get() = null
         set(_) = error("We should never need to store metadata of external declarations.")
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitClass(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        thisReceiver?.accept(visitor, data)
-        typeParameters.forEach { it.accept(visitor, data) }
-        declarations.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        thisReceiver = thisReceiver?.transform(transformer, data)
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-        declarations.transform { it.transform(transformer, data) }
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyConstructor.kt

@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.ir.symbols.IrConstructorSymbol
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
 import org.jetbrains.kotlin.ir.util.withScope
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
@@ -56,7 +55,4 @@ class IrLazyConstructor(
     init {
         symbol.bind(this)
     }
-
+}
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitConstructor(this, data)
-}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyEnumEntryImpl.kt

@@ -25,8 +25,6 @@ import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrEnumEntrySymbol
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
@@ -50,18 +48,4 @@ class IrLazyEnumEntryImpl(
     override var correspondingClass: IrClass? = null
 
     override var initializerExpression: IrExpressionBody? = null
-
+}
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitEnumEntry(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        initializerExpression?.accept(visitor, data)
-        correspondingClass?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        initializerExpression = initializerExpression?.transform(transformer, data)
-        correspondingClass = correspondingClass?.transform(transformer, data) as? IrClass
-    }
-}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyField.kt

@@ -19,8 +19,6 @@ import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
@@ -69,16 +67,4 @@ class IrLazyField(
     override var metadata: MetadataSource?
         get() = null
         set(_) = error("We should never need to store metadata of external declarations.")
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitField(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        initializer?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        initializer = initializer?.transform(transformer, data)
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyFunction.kt

@@ -15,7 +15,6 @@ import org.jetbrains.kotlin.ir.symbols.IrSimpleFunctionSymbol
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
 import org.jetbrains.kotlin.ir.util.withScope
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.descriptorUtil.propertyIfAccessor
 
@@ -73,7 +72,4 @@ class IrLazyFunction(
     init {
         symbol.bind(this)
     }
-
+}
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitSimpleFunction(this, data)
-}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyFunctionBase.kt

@@ -15,9 +15,6 @@ import org.jetbrains.kotlin.ir.expressions.IrBody
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
@@ -70,24 +67,4 @@ abstract class IrLazyFunctionBase(
     override var metadata: MetadataSource?
         get() = null
         set(_) = error("We should never need to store metadata of external declarations.")
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        typeParameters.forEach { it.accept(visitor, data) }
-
-        dispatchReceiverParameter?.accept(visitor, data)
-        extensionReceiverParameter?.accept(visitor, data)
-        valueParameters.forEach { it.accept(visitor, data) }
-
-        body?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-
-        dispatchReceiverParameter = dispatchReceiverParameter?.transform(transformer, data)
-        extensionReceiverParameter = extensionReceiverParameter?.transform(transformer, data)
-        valueParameters = valueParameters.transformIfNeeded(transformer, data)
-
-        body = body?.transform(transformer, data)
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyProperty.kt

@@ -13,8 +13,6 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.symbols.IrPropertySymbol
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.hasBackingField
@@ -73,19 +71,4 @@ class IrLazyProperty(
     override var metadata: MetadataSource?
         get() = null
         set(_) = error("We should never need to store metadata of external declarations.")
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitProperty(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        backingField?.accept(visitor, data)
-        getter?.accept(visitor, data)
-        setter?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        backingField = backingField?.transform(transformer, data) as? IrField
-        getter = getter?.run { transform(transformer, data) as IrSimpleFunction }
-        setter = setter?.run { transform(transformer, data) as IrSimpleFunction }
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyTypeAlias.kt

@@ -16,9 +16,6 @@ import org.jetbrains.kotlin.ir.symbols.IrTypeAliasSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.util.transformIfNeeded
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 
 @OptIn(ObsoleteDescriptorBasedAPI::class)
@@ -54,15 +51,4 @@ class IrLazyTypeAlias(
             }
         }
     }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitTypeAlias(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        typeParameters.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        typeParameters = typeParameters.transformIfNeeded(transformer, data)
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/declarations/lazy/IrLazyTypeParameter.kt

@@ -15,8 +15,6 @@ import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
 import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.DeclarationStubGenerator
 import org.jetbrains.kotlin.ir.util.TypeTranslator
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.Variance
 
@@ -49,18 +47,4 @@ class IrLazyTypeParameter(
             }
         }
     }
-
+}
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitTypeParameter(this, data)
-
-    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrTypeParameter =
-        transformer.visitTypeParameter(this, data) as IrTypeParameter
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        // no children
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        // no children
-    }
-}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/IrBody.kt

@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.ir.expressions
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrFactory
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 interface IrBody : IrElement {
     override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrBody =
@@ -30,12 +31,36 @@ interface IrExpressionBody : IrBody {
 
     var expression: IrExpression
 
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitExpressionBody(this, data)
+
     override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrExpressionBody =
         accept(transformer, data) as IrExpressionBody
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        expression.accept(visitor, data)
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        expression = expression.transform(transformer, data)
+    }
 }
 
 interface IrBlockBody : IrBody, IrStatementContainer {
     val factory: IrFactory
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+        visitor.visitBlockBody(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        statements.forEach { it.accept(visitor, data) }
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        statements.forEachIndexed { i, irStatement ->
+            statements[i] = irStatement.transform(transformer, data)
+        }
+    }
 }
 
 interface IrSyntheticBody : IrBody {

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/impl/IrBlockBodyImpl.kt

@@ -21,8 +21,6 @@ import org.jetbrains.kotlin.ir.declarations.IrFactory
 import org.jetbrains.kotlin.ir.declarations.impl.IrBodyBase
 import org.jetbrains.kotlin.ir.declarations.impl.IrFactoryImpl
 import org.jetbrains.kotlin.ir.expressions.IrBlockBody
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 class IrBlockBodyImpl(
     startOffset: Int,
@@ -43,18 +41,4 @@ class IrBlockBodyImpl(
 
     override val factory: IrFactory
         get() = IrFactoryImpl
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
-        return visitor.visitBlockBody(this, data)
-    }
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        statements.forEach { it.accept(visitor, data) }
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        statements.forEachIndexed { i, irStatement ->
-            statements[i] = irStatement.transform(transformer, data)
-        }
-    }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/impl/IrExpressionBodyImpl.kt

@@ -21,8 +21,6 @@ import org.jetbrains.kotlin.ir.declarations.impl.IrBodyBase
 import org.jetbrains.kotlin.ir.declarations.impl.IrFactoryImpl
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 
 class IrExpressionBodyImpl private constructor(
     startOffset: Int,
@@ -38,7 +36,7 @@ class IrExpressionBodyImpl private constructor(
     constructor(startOffset: Int, endOffset: Int, expression: IrExpression) : this(startOffset, endOffset, expression, null)
 
     constructor(startOffset: Int, endOffset: Int, initializer: IrExpressionBody.() -> Unit) :
-        this(startOffset, endOffset, null, initializer)
+            this(startOffset, endOffset, null, initializer)
 
     override var expression: IrExpression
         get() = checkEnabled { expressionField!! }
@@ -48,15 +46,4 @@ class IrExpressionBodyImpl private constructor(
 
     override val factory: IrFactory
         get() = IrFactoryImpl
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-        visitor.visitExpressionBody(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        expression.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        expression = expression.transform(transformer, data)
-    }
 }