JVM IR: remove obsolete hack in JvmMultifileClass facade generation

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

@@ -10,21 +10,9 @@ import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.util.DescriptorsRemapper
-import org.jetbrains.kotlin.ir.util.deepCopyWithSymbols
 import org.jetbrains.kotlin.ir.util.parentAsClass
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
-import org.jetbrains.kotlin.ir.visitors.acceptVoid
-
-/*
-    TODO: Does not preserve getter/setter descriptors as implementations of PropertyAccessorDescriptor.
-    This causes problems for KotlinTypeMapper.mapFunctionName (maybe other places as well)
- */
-
-inline fun <reified T : IrElement> T.deepCopyWithWrappedDescriptors(initialParent: IrDeclarationParent? = null): T =
-    deepCopyWithSymbols(initialParent, DescriptorsToIrRemapper).also {
-        it.acceptVoid(WrappedDescriptorPatcher)
-    }
 
 object DescriptorsToIrRemapper : DescriptorsRemapper {
     override fun remapDeclaredClass(descriptor: ClassDescriptor) =

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

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.backend.jvm.lower
 
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
-import org.jetbrains.kotlin.backend.common.deepCopyWithWrappedDescriptors
 import org.jetbrains.kotlin.backend.common.ir.createImplicitParameterDeclarationWithWrappedDescriptor
 import org.jetbrains.kotlin.backend.common.ir.passTypeArgumentsFrom
 import org.jetbrains.kotlin.backend.common.lower
@@ -22,9 +21,7 @@ import org.jetbrains.kotlin.backend.jvm.codegen.fileParent
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.descriptors.impl.EmptyPackageFragmentDescriptor
-import org.jetbrains.kotlin.ir.SourceManager
-import org.jetbrains.kotlin.ir.SourceRangeInfo
-import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
+import org.jetbrains.kotlin.ir.*
 import org.jetbrains.kotlin.ir.builders.declarations.buildClass
 import org.jetbrains.kotlin.ir.builders.irBlockBody
 import org.jetbrains.kotlin.ir.builders.irCall
@@ -42,8 +39,8 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
 import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
 import org.jetbrains.kotlin.ir.util.deepCopyWithSymbols
-import org.jetbrains.kotlin.ir.util.dump
 import org.jetbrains.kotlin.ir.util.transformFlat
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.resolve.jvm.JvmClassName
@@ -163,8 +160,7 @@ private fun IrFunction.createMultifileDelegateIfNeeded(context: JvmBackendContex
     // TODO: perform copy of the signature only, without body
     val function = deepCopyWithSymbols(facadeClass)
     function.body = context.createIrBuilder(symbol).irBlockBody {
-        val functionForCall = computeFunctionForCall()
-        +irReturn(irCall(functionForCall).also { call ->
+        +irReturn(irCall(this@createMultifileDelegateIfNeeded).also { call ->
             call.passTypeArgumentsFrom(function)
             function.extensionReceiverParameter?.let { parameter ->
                 call.extensionReceiver = irGet(parameter)
@@ -181,22 +177,6 @@ private fun IrFunction.createMultifileDelegateIfNeeded(context: JvmBackendContex
     return function
 }
 
-// This deep copy is needed while we still use KotlinTypeMapper to map signatures in method calls. Without it, KotlinTypeMapper takes
-// the descriptor and assumes that a call to that function must go through the public facade (see mapOwner call in mapToCallableMethod),
-// which results in endless recursion here. With this copy, we trick it into thinking that the function is actually a static function
-// in a class whose name is the name of the multi-file part, as opposed to being top level.
-private fun IrFunction.computeFunctionForCall(): IrFunction {
-    val property = (this as? IrSimpleFunction)?.correspondingPropertySymbol?.owner
-        ?: return deepCopyWithWrappedDescriptors(parent)
-
-    val propertyCopy = property.deepCopyWithWrappedDescriptors(property.parent)
-    return when (this) {
-        property.getter -> propertyCopy.getter!!
-        property.setter -> propertyCopy.setter!!
-        else -> error("Property accessor must be getter or setter: ${dump()}")
-    }
-}
-
 private class UpdateFieldCallSites(
     private val movedFields: Map<IrFieldSymbol, IrFieldSymbol>
 ) : FileLoweringPass, IrElementTransformerVoid() {
@@ -214,13 +194,21 @@ private class UpdateFieldCallSites(
 
 private class UpdateFunctionCallSites(
     private val functionDelegates: MutableMap<IrFunctionSymbol, IrFunctionSymbol>
-) : FileLoweringPass, IrElementTransformerVoid() {
+) : FileLoweringPass, IrElementTransformer<IrFunction?> {
     override fun lower(irFile: IrFile) {
-        irFile.transformChildrenVoid(this)
+        irFile.transformChildren(this, null)
     }
 
-    override fun visitCall(expression: IrCall): IrExpression {
-        val newFunction = functionDelegates[expression.symbol] ?: return super.visitCall(expression)
+    override fun visitFunction(declaration: IrFunction, data: IrFunction?): IrStatement =
+        super.visitFunction(declaration, declaration)
+
+    override fun visitCall(expression: IrCall, data: IrFunction?): IrElement {
+        if (data?.origin == JvmLoweredDeclarationOrigin.MULTIFILE_BRIDGE)
+            return super.visitCall(expression, data)
+
+        val newFunction = functionDelegates[expression.symbol]
+            ?: return super.visitCall(expression, data)
+
         return expression.run {
             // TODO: deduplicate this with ReplaceKFunctionInvokeWithFunctionInvoke
             IrCallImpl(startOffset, endOffset, type, newFunction).apply {

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

@@ -33,11 +33,8 @@ import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import java.util.*
 
-inline fun <reified T : IrElement> T.deepCopyWithSymbols(
-    initialParent: IrDeclarationParent? = null,
-    descriptorRemapper: DescriptorsRemapper = DescriptorsRemapper.Default
-): T {
-    val symbolRemapper = DeepCopySymbolRemapper(descriptorRemapper)
+inline fun <reified T : IrElement> T.deepCopyWithSymbols(initialParent: IrDeclarationParent? = null): T {
+    val symbolRemapper = DeepCopySymbolRemapper()
     acceptVoid(symbolRemapper)
     val typeRemapper = DeepCopyTypeRemapper(symbolRemapper)
     return transform(DeepCopyIrTreeWithSymbols(symbolRemapper, typeRemapper), null).patchDeclarationParents(initialParent) as T

compiler/testData/codegen/box/jvmName/multifileClassWithLocalGeneric.kt

@@ -1,6 +1,4 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
-
 // WITH_RUNTIME
 
 @file:JvmName("Test")