JVM_IR: do not inline reads of constructor arguments into accessors

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java

@@ -13316,6 +13316,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @Test
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @Test
         @TestMetadata("delegateToGenericJavaProperty.kt")
         public void testDelegateToGenericJavaProperty() throws Exception {

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

@@ -59,7 +59,7 @@ val IrDeclaration.parentsWithSelf: Sequence<IrDeclarationParent>
     get() = generateSequence(this as? IrDeclarationParent) { (it as? IrDeclaration)?.parent }
 
 val IrDeclaration.parents: Sequence<IrDeclarationParent>
-    get() = parentsWithSelf.drop(1)
+    get() = generateSequence(parent) { (it as? IrDeclaration)?.parent }
 
 object BOUND_VALUE_PARAMETER : IrDeclarationOriginImpl("BOUND_VALUE_PARAMETER")
 

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

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.backend.jvm.lower
 
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
+import org.jetbrains.kotlin.backend.common.lower.parents
 import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.backend.jvm.codegen.fileParent
@@ -85,14 +86,16 @@ private class PropertyReferenceDelegationTransformer(val context: JvmBackendCont
     private val IrStatement.isStdlibCall: Boolean
         get() = this is IrCall && symbol.owner.getPackageFragment()?.fqName == StandardNames.BUILT_INS_PACKAGE_FQ_NAME
 
-    // Constants, object accesses, reads of immutable variables, and reads of immutable properties in the same file
+    // Some receivers don't need to be stored in fields and can be reevaluated every time an accessor is called:
-    // don't need to be cached in a field; reads of mutable properties have to be as we should ignore further assignments
+    private fun IrExpression.canInline(visibleScopes: Set<IrDeclarationParent>): Boolean = when (this) {
-    // to those, and immutable properties in other files might become mutable without breaking ABI.
+        // Reads of immutable variables are stable, but value parameters of the constructor are not in scope:
-    private fun IrExpression.canInline(currentFile: IrFile): Boolean = when (this) {
+        is IrGetValue -> symbol.owner.let { !(it is IrVariable && it.isVar) && it.parent in visibleScopes }
-        is IrGetValue -> !symbol.owner.let { it is IrVariable && it.isVar }
+        // Reads of final fields of stable values are stable, but fields in other files can become non-final:
-        is IrGetField -> symbol.owner.let { it.isFinal && it.fileParent == currentFile } && receiver?.canInline(currentFile) != false
+        is IrGetField -> symbol.owner.let { it.isFinal && it.fileParent in visibleScopes } && receiver?.canInline(visibleScopes) != false
-        is IrCall -> symbol.owner.let { it.isFinalDefaultValGetter && it.fileParent == currentFile } &&
+        // Same applies to reads of properties with default getters, but non-final properties may be overridden by `var`s:
-                dispatchReceiver?.canInline(currentFile) != false && extensionReceiver?.canInline(currentFile) != false
+        is IrCall -> symbol.owner.let { it.isFinalDefaultValGetter && it.fileParent in visibleScopes } &&
+                dispatchReceiver?.canInline(visibleScopes) != false && extensionReceiver?.canInline(visibleScopes) != false
+        // Constants and singleton object accesses are always stable:
         else -> isTrivial()
     }
 
@@ -134,7 +137,7 @@ private class PropertyReferenceDelegationTransformer(val context: JvmBackendCont
 
         val receiver = (delegate.dispatchReceiver ?: delegate.extensionReceiver)
             ?.transform(this@PropertyReferenceDelegationTransformer, null)
-        backingField = receiver?.takeIf { !it.canInline(fileParent) }?.let {
+        backingField = receiver?.takeIf { !it.canInline(parents.toSet()) }?.let {
             context.irFactory.buildField {
                 updateFrom(oldField)
                 name = Name.identifier("${this@transform.name}\$receiver")

compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt

@@ -0,0 +1,8 @@
+// WITH_RUNTIME
+class C(val x: String)
+
+class D(c: C) {
+    val x by c::x
+}
+
+fun box(): String = D(C("OK")).x

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BlackBoxCodegenTestGenerated.java

@@ -13256,6 +13256,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @Test
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @Test
         @TestMetadata("delegateToGenericJavaProperty.kt")
         public void testDelegateToGenericJavaProperty() throws Exception {

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java

@@ -13316,6 +13316,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @Test
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @Test
         @TestMetadata("delegateToGenericJavaProperty.kt")
         public void testDelegateToGenericJavaProperty() throws Exception {

compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -10775,6 +10775,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @TestMetadata("delegateToGenericJavaProperty.kt")
         public void testDelegateToGenericJavaProperty() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToGenericJavaProperty.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/es6/semantics/IrJsCodegenBoxES6TestGenerated.java

@@ -9584,6 +9584,11 @@ public class IrJsCodegenBoxES6TestGenerated extends AbstractIrJsCodegenBoxES6Tes
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @TestMetadata("delegateToOpenProperty.kt")
         public void testDelegateToOpenProperty() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToOpenProperty.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/semantics/IrJsCodegenBoxTestGenerated.java

@@ -8990,6 +8990,11 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @TestMetadata("delegateToOpenProperty.kt")
         public void testDelegateToOpenProperty() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToOpenProperty.kt");

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/semantics/JsCodegenBoxTestGenerated.java

@@ -8990,6 +8990,11 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToAnotherWithSideEffects.kt");
         }
 
+        @TestMetadata("delegateToConstructorParameter.kt")
+        public void testDelegateToConstructorParameter() throws Exception {
+            runTest("compiler/testData/codegen/box/delegatedProperty/delegateToConstructorParameter.kt");
+        }
+
         @TestMetadata("delegateToOpenProperty.kt")
         public void testDelegateToOpenProperty() throws Exception {
             runTest("compiler/testData/codegen/box/delegatedProperty/delegateToOpenProperty.kt");