Add 'parent' to IrDeclaration, initialize it with a hack (for migration)

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/Psi2IrTranslator.kt

@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.psi2ir
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
+import org.jetbrains.kotlin.ir.util.patchDeclarationParents
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi2ir.generators.GeneratorContext
 import org.jetbrains.kotlin.psi2ir.generators.ModuleGenerator
@@ -55,5 +56,7 @@ class Psi2IrTranslator(val configuration: Psi2IrConfiguration = Psi2IrConfigurat
         insertImplicitCasts(context.builtIns, irElement)
 
         postprocessingSteps.forEach { it.postprocess(context, irElement) }
+
+        irElement.patchDeclarationParents()
     }
 }

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

@@ -31,6 +31,8 @@ interface IrDeclaration : IrStatement {
     val declarationKind: IrDeclarationKind
     val origin: IrDeclarationOrigin
 
+    val parent: IrDeclarationParent
+
     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/IrDeclarationContainer.kt

@@ -16,6 +16,8 @@
 
 package org.jetbrains.kotlin.ir.declarations
 
-interface IrDeclarationContainer {
+interface IrDeclarationParent
+
+interface IrDeclarationContainer : IrDeclarationParent {
     val declarations: MutableList<IrDeclaration>
 }

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

@@ -24,7 +24,7 @@ import org.jetbrains.kotlin.ir.expressions.IrExpressionBody
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.types.KotlinType
 
-interface IrFunction : IrDeclaration, IrTypeParametersContainer, IrSymbolOwner {
+interface IrFunction : IrDeclaration, IrTypeParametersContainer, IrSymbolOwner, IrDeclarationParent {
     override val descriptor: FunctionDescriptor
     override val symbol: IrFunctionSymbol
 

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

@@ -19,9 +19,14 @@ package org.jetbrains.kotlin.ir.declarations.impl
 import org.jetbrains.kotlin.ir.IrElementBase
 import org.jetbrains.kotlin.ir.declarations.IrDeclaration
 import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationParent
 
 abstract class IrDeclarationBase(
     startOffset: Int,
     endOffset: Int,
     override val origin: IrDeclarationOrigin
-) : IrElementBase(startOffset, endOffset), IrDeclaration
+) : IrElementBase(startOffset, endOffset),
+    IrDeclaration {
+
+    override lateinit var parent: IrDeclarationParent
+}

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

@@ -31,8 +31,8 @@ import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.types.KotlinType
 import java.util.*
 
-inline fun <reified T : IrElement> T.deepCopyOld() =
-    transform(DeepCopyIrTree(), null) as T
+inline fun <reified T : IrElement> T.deepCopyOld(): T =
+    transform(DeepCopyIrTree(), null).patchDeclarationParents() as T
 
 @Deprecated("Creates unbound symbols")
 open class DeepCopyIrTree : IrElementTransformerVoid() {

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

@@ -32,7 +32,7 @@ import java.util.*
 inline fun <reified T : IrElement> T.deepCopyWithSymbols(): T {
     val remapper = DeepCopySymbolsRemapper()
     acceptVoid(remapper)
-    return transform(DeepCopyIrTreeWithSymbols(remapper), null) as T
+    return transform(DeepCopyIrTreeWithSymbols(remapper), null).patchDeclarationParents() as T
 }
 
 

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

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.ir.util
+
+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.impl.IrDeclarationBase
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
+import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
+import org.jetbrains.kotlin.ir.visitors.acceptVoid
+import java.util.*
+
+fun <T : IrElement> T.patchDeclarationParents() =
+    apply {
+        acceptVoid(PatchDeclarationParentsVisitor())
+    }
+
+class PatchDeclarationParentsVisitor : IrElementVisitorVoid {
+
+    private val declarationParentsStack = ArrayDeque<IrDeclarationParent>()
+
+    override fun visitElement(element: IrElement) {
+        element.acceptChildrenVoid(this)
+    }
+
+    override fun visitPackageFragment(declaration: IrPackageFragment) {
+        declarationParentsStack.push(declaration)
+        super.visitPackageFragment(declaration)
+        declarationParentsStack.pop()
+    }
+
+    override fun visitDeclaration(declaration: IrDeclaration) {
+        patchParent(declaration)
+
+        if (declaration is IrDeclarationParent) {
+            declarationParentsStack.push(declaration)
+        }
+
+        super.visitDeclaration(declaration)
+
+        if (declaration is IrDeclarationParent) {
+            declarationParentsStack.pop()
+        }
+    }
+
+    private fun patchParent(declaration: IrDeclaration) {
+        (declaration as IrDeclarationBase).parent = declarationParentsStack.peekFirst()
+    }
+}