Generate reference to existing class for builtin function references

Instead of non-existing `kotlin.KotlinPackage`, which led to
NoClassDefFoundError as soon as reflection tried to call getOwner on a
builtin callable reference, use a reference to a new physical class
`kotlin.jvm.internal.Intrinsics$Kotlin`. This will allow to support
KT-17151.

Note that for API version less than 1.4, this will still lead to
NoClassDefFoundError, but this is not worse than the current situation
where it happens anyway.

compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.kt

@@ -1313,7 +1313,7 @@ class KotlinTypeMapper @JvmOverloads constructor(
             return JvmClassName.byClassId(ownerClassId).internalName
         }
 
-        private val FAKE_CLASS_ID_FOR_BUILTINS = ClassId.topLevel(FqName("kotlin.KotlinPackage"))
+        private val FAKE_CLASS_ID_FOR_BUILTINS = ClassId(FqName("kotlin.jvm.internal"), FqName("Intrinsics.Kotlin"), false)
 
         private fun getPackageMemberContainingClassesInfo(descriptor: DescriptorWithContainerSource): ContainingClassesInfo? {
             val containingDeclaration = descriptor.containingDeclaration

compiler/fir/fir2ir/tests/org/jetbrains/kotlin/codegen/ir/FirBlackBoxCodegenTestGenerated.java

@@ -1963,6 +1963,11 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), null, TargetBackend.JVM_IR, true);
         }
 
+        @TestMetadata("builtinFunctionReferenceOwner.kt")
+        public void testBuiltinFunctionReferenceOwner() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/builtinFunctionReferenceOwner.kt");
+        }
+
         @TestMetadata("classesAreSynthetic.kt")
         public void testClassesAreSynthetic() throws Exception {
             runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmSymbols.kt

@@ -19,9 +19,10 @@ import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.Visibilities
 import org.jetbrains.kotlin.descriptors.impl.EmptyPackageFragmentDescriptor
 import org.jetbrains.kotlin.ir.builders.declarations.*
-import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.declarations.IrClass
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
+import org.jetbrains.kotlin.ir.declarations.IrPackageFragment
 import org.jetbrains.kotlin.ir.declarations.impl.IrExternalPackageFragmentImpl
-import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.symbols.*
 import org.jetbrains.kotlin.ir.symbols.impl.IrExternalPackageFragmentSymbolImpl
 import org.jetbrains.kotlin.ir.types.*
@@ -134,6 +135,13 @@ class JvmSymbols(
             addValueParameter("object", irBuiltIns.anyNType)
         }
         klass.addFunction("throwNpe", irBuiltIns.unitType, isStatic = true)
+
+        klass.declarations.add(buildClass {
+            name = Name.identifier("Kotlin")
+        }.apply {
+            parent = klass
+            createImplicitParameterDeclarationWithWrappedDescriptor()
+        })
     }
 
     val checkExpressionValueIsNotNull: IrSimpleFunctionSymbol =
@@ -154,6 +162,9 @@ class JvmSymbols(
     val intrinsicStringPlus: IrFunctionSymbol =
         intrinsicsClass.functions.single { it.owner.name.asString() == "stringPlus" }
 
+    val intrinsicsKotlinClass: IrClassSymbol =
+        (intrinsicsClass.owner.declarations.single { it is IrClass && it.name.asString() == "Kotlin" } as IrClass).symbol
+
     override val stringBuilder: IrClassSymbol = createClass(FqName("java.lang.StringBuilder")) { klass ->
         klass.addConstructor()
         klass.addFunction("toString", irBuiltIns.stringType).apply {

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

@@ -370,9 +370,15 @@ internal class CallableReferenceLowering(private val context: JvmBackendContext)
             kClassToJavaClass(kClassReference(classType), context)
 
         internal fun IrBuilderWithScope.calculateOwner(irContainer: IrDeclarationParent, context: JvmBackendContext): IrExpression {
-            // For built-in members (i.e. top level `toString`) we don't know any meaningful container, so we're generating Any.
-            // The non-IR backend generates equally meaningless "kotlin/KotlinPackage" in this case (see KT-17151).
-            val kClass = kClassReference((irContainer as? IrClass)?.defaultType ?: context.irBuiltIns.anyNType)
+            val classType =
+                if (irContainer is IrClass) irContainer.defaultType
+                else {
+                    // For built-in members (i.e. top level `toString`) we generate reference to an internal class for an owner.
+                    // This allows kotlin-reflect to understand that this is a built-in intrinsic which has no real declaration,
+                    // and construct a special KCallable object.
+                    context.ir.symbols.intrinsicsKotlinClass.defaultType
+                }
+            val kClass = kClassReference(classType)
 
             if ((irContainer as? IrClass)?.isFileClass != true && irContainer !is IrPackageFragment)
                 return kClass

compiler/testData/codegen/box/callableReference/builtinFunctionReferenceOwner.kt

@@ -0,0 +1,12 @@
+// TARGET_BACKEND: JVM
+// IGNORE_BACKEND_FIR: JVM_IR
+// WITH_RUNTIME
+
+fun box(): String {
+    val f = Any?::toString
+
+    val owner = (f as kotlin.jvm.internal.CallableReference).owner as kotlin.jvm.internal.PackageReference
+    if (owner.jClass.name != "kotlin.jvm.internal.Intrinsics\$Kotlin") return "Fail: $owner"
+
+    return "OK"
+}

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -1983,6 +1983,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), null, TargetBackend.JVM, true);
         }
 
+        @TestMetadata("builtinFunctionReferenceOwner.kt")
+        public void testBuiltinFunctionReferenceOwner() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/builtinFunctionReferenceOwner.kt");
+        }
+
         @TestMetadata("classesAreSynthetic.kt")
         public void testClassesAreSynthetic() throws Exception {
             runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");

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

@@ -1983,6 +1983,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), null, TargetBackend.JVM, true);
         }
 
+        @TestMetadata("builtinFunctionReferenceOwner.kt")
+        public void testBuiltinFunctionReferenceOwner() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/builtinFunctionReferenceOwner.kt");
+        }
+
         @TestMetadata("classesAreSynthetic.kt")
         public void testClassesAreSynthetic() throws Exception {
             runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");

compiler/tests/org/jetbrains/kotlin/codegen/ir/IrBlackBoxCodegenTestGenerated.java

@@ -1963,6 +1963,11 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/codegen/box/callableReference"), Pattern.compile("^(.+)\\.kt$"), null, TargetBackend.JVM_IR, true);
         }
 
+        @TestMetadata("builtinFunctionReferenceOwner.kt")
+        public void testBuiltinFunctionReferenceOwner() throws Exception {
+            runTest("compiler/testData/codegen/box/callableReference/builtinFunctionReferenceOwner.kt");
+        }
+
         @TestMetadata("classesAreSynthetic.kt")
         public void testClassesAreSynthetic() throws Exception {
             runTest("compiler/testData/codegen/box/callableReference/classesAreSynthetic.kt");

libraries/stdlib/jvm/runtime/kotlin/jvm/internal/Intrinsics.java

@@ -266,4 +266,11 @@ public class Intrinsics {
         throwable.setStackTrace(newStackTrace);
         return throwable;
     }
+
+    // Stub class which is used as an owner of callable references for built-ins declared in package "kotlin".
+    @SinceKotlin(version = "1.4")
+    public static class Kotlin {
+        private Kotlin() {
+        }
+    }
 }

libraries/tools/binary-compatibility-validator/reference-public-api/kotlin-stdlib-runtime-merged.txt

@@ -3437,6 +3437,9 @@ public class kotlin/jvm/internal/Intrinsics {
 	public static fun throwUninitializedPropertyAccessException (Ljava/lang/String;)V
 }
 
+public class kotlin/jvm/internal/Intrinsics$Kotlin {
+}
+
 public abstract class kotlin/jvm/internal/Lambda : java/io/Serializable, kotlin/jvm/internal/FunctionBase {
 	public fun <init> (I)V
 	public fun getArity ()I