Optimize ir interpretation of Enum.name

There is no need to create honest object in case of such simple
calculation. Furthermore, it can be harmful if enum class has
non-constant initializer or property.

#KT-53480 Fixed

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

@@ -8133,6 +8133,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/constants/foldingBinaryOpsUnsignedConst.kt");
         }
 
+        @Test
+        @TestMetadata("kt53480.kt")
+        public void testKt53480() throws Exception {
+            runTest("compiler/testData/codegen/box/constants/kt53480.kt");
+        }
+
         @Test
         @TestMetadata("kt9532.kt")
         public void testKt9532() throws Exception {

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/InstructionsUnfolder.kt

@@ -90,7 +90,8 @@ private fun unfoldFunction(function: IrSimpleFunction, environment: IrInterprete
 
 private fun unfoldConstructor(constructor: IrConstructor, callStack: CallStack) {
     when (constructor.fqName) {
-        "kotlin.Enum.<init>", "kotlin.Throwable.<init>" -> {
+        "kotlin.Enum.<init>" -> return // all properties already initialized in `interpretEnumEntry`
+        "kotlin.Throwable.<init>" -> {
             val irClass = constructor.parentAsClass
             val receiverSymbol = irClass.thisReceiver!!.symbol
             val receiverState = callStack.loadState(receiverSymbol)
@@ -196,11 +197,15 @@ private fun unfoldEnumConstructorCall(element: IrEnumConstructorCall, environmen
 private fun unfoldInstanceInitializerCall(instanceInitializerCall: IrInstanceInitializerCall, callStack: CallStack) {
     val irClass = instanceInitializerCall.classSymbol.owner
     val toInitialize = irClass.declarations.filter { it is IrProperty || it is IrAnonymousInitializer }
+    val state = irClass.thisReceiver?.symbol?.let { callStack.loadState(it) } // try to avoid recalculation of properties
 
     toInitialize.reversed().forEach {
         when {
             it is IrAnonymousInitializer -> callStack.pushCompoundInstruction(it.body)
-            it is IrProperty && it.backingField?.initializer?.expression != null -> callStack.pushCompoundInstruction(it.backingField)
+
+            it is IrProperty && it.backingField?.initializer?.expression != null && state?.getField(it.symbol) == null -> {
+                callStack.pushCompoundInstruction(it.backingField)
+            }
         }
     }
 }
@@ -272,6 +277,14 @@ private fun unfoldGetEnumValue(expression: IrGetEnumValue, environment: IrInterp
     val callStack = environment.callStack
     environment.mapOfEnums[expression.symbol]?.let { return callStack.pushState(it) }
 
+    val frameOwner = callStack.currentFrameOwner
+    if (frameOwner is IrCall && frameOwner.dispatchReceiver is IrGetEnumValue && frameOwner.symbol.owner.name.asString() == "<get-name>") {
+        // this optimization allow us to avoid creation of enum object when we try to interpret simple `name` call; see KT-53480
+        val enumEntry = (frameOwner.dispatchReceiver as IrGetEnumValue).symbol.owner
+        callStack.pushState(enumEntry.toState(environment.irBuiltIns))
+        return
+    }
+
     callStack.pushSimpleInstruction(expression)
     val enumEntry = expression.symbol.owner
     val enumClass = enumEntry.symbol.owner.parentAsClass

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/IrInterpreter.kt

@@ -206,7 +206,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
         if (callStack.peekState() == null) callStack.pushState(getUnitState()) // implicit Unit result
     }
 
-    @Suppress("UNUSED_PARAMETER")
     private fun interpretConstructor(constructor: IrConstructor) {
         callStack.pushState(callStack.loadState(constructor.parentAsClass.thisReceiver!!.symbol))
         callStack.dropFrameAndCopyResult()
@@ -390,28 +389,14 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
 
     private fun interpretEnumEntry(enumEntry: IrEnumEntry) {
         callInterceptor.interceptEnumEntry(enumEntry) {
-            val enumClass = enumEntry.symbol.owner.parentAsClass
-            val enumEntries = enumClass.declarations.filterIsInstance<IrEnumEntry>()
+            val enumClassObject = enumEntry.toState(irBuiltIns)
+            environment.mapOfEnums[enumEntry.symbol] = enumClassObject
+
             val enumInitializer = enumEntry.initializerExpression?.expression
                 ?: throw InterpreterError("Initializer at enum entry ${enumEntry.fqName} is null")
             val enumConstructorCall = enumInitializer as? IrEnumConstructorCall
                 ?: (enumInitializer as IrBlock).statements.filterIsInstance<IrEnumConstructorCall>().single()
 
-            val enumClassObject = Common(enumEntry.correspondingClass ?: enumClass)
-            environment.mapOfEnums[enumEntry.symbol] = enumClassObject
-
-            if (enumEntries.isNotEmpty()) {
-                // these fields will be evaluated during interpretation of constructor call
-                // but we need them right away to create correct call to Enum's constructor
-                val valueArguments = listOf(
-                    Primitive(enumEntry.name.asString(), irBuiltIns.stringType),
-                    Primitive(enumEntries.indexOf(enumEntry), irBuiltIns.intType)
-                )
-                irBuiltIns.enumClass.owner.declarations.filterIsInstance<IrProperty>().zip(valueArguments).forEach { (property, argument) ->
-                    enumClassObject.setField(property.symbol, argument)
-                }
-            }
-
             callStack.newSubFrame(enumEntry)
             callStack.pushCompoundInstruction(enumEntry) // not really a compound instruction
             callStack.pushCompoundInstruction(enumInitializer)

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/Utils.kt

@@ -9,6 +9,7 @@ import org.jetbrains.kotlin.builtins.PrimitiveType
 import org.jetbrains.kotlin.builtins.StandardNames
 import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.ir.IrBuiltIns
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
@@ -312,3 +313,21 @@ internal fun State.unsignedToString(): String {
         else -> (value as Number).toLong().toULong().toString()
     }
 }
+
+internal fun IrEnumEntry.toState(irBuiltIns: IrBuiltIns): Common {
+    val enumClass = this.symbol.owner.parentAsClass
+    val enumEntries = enumClass.declarations.filterIsInstance<IrEnumEntry>()
+    val enumClassObject = Common(this.correspondingClass ?: enumClass)
+
+    if (enumEntries.isNotEmpty()) {
+        val valueArguments = listOf(
+            Primitive(this.name.asString(), irBuiltIns.stringType),
+            Primitive(enumEntries.indexOf(this), irBuiltIns.intType)
+        )
+        irBuiltIns.enumClass.owner.declarations.filterIsInstance<IrProperty>().zip(valueArguments).forEach { (property, argument) ->
+            enumClassObject.setField(property.symbol, argument)
+        }
+    }
+
+    return enumClassObject
+}

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/intrinsics/IntrinsicEvaluator.kt

@@ -11,7 +11,6 @@ import org.jetbrains.kotlin.ir.interpreter.IrInterpreterEnvironment
 import org.jetbrains.kotlin.ir.interpreter.fqName
 
 internal object IntrinsicEvaluator {
-    @OptIn(ExperimentalStdlibApi::class)
     private val fqNameToHandler: Map<String, IntrinsicBase> = buildMap {
         listOf(
             EmptyArray, ArrayOf, ArrayOfNulls, ArrayConstructor, EnumValues, EnumValueOf,

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/intrinsics/IntrinsicImplementations.kt

@@ -7,9 +7,6 @@ package org.jetbrains.kotlin.ir.interpreter.intrinsics
 
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.interpreter.*
-import org.jetbrains.kotlin.ir.interpreter.createCall
-import org.jetbrains.kotlin.ir.interpreter.createGetValue
-import org.jetbrains.kotlin.ir.interpreter.toIrConst
 import org.jetbrains.kotlin.ir.interpreter.exceptions.handleUserException
 import org.jetbrains.kotlin.ir.interpreter.exceptions.stop
 import org.jetbrains.kotlin.ir.interpreter.exceptions.withExceptionHandler
@@ -30,7 +27,7 @@ internal sealed class IntrinsicBase {
         return listOf(customEvaluateInstruction(irFunction, environment))
     }
 
-    fun customEvaluateInstruction(irFunction: IrFunction, environment: IrInterpreterEnvironment): CustomInstruction {
+    private fun customEvaluateInstruction(irFunction: IrFunction, environment: IrInterpreterEnvironment): CustomInstruction {
         return CustomInstruction {
             withExceptionHandler(environment) { // Exception handling is used only for indent actions; TODO: drop later
                 evaluate(irFunction, environment)
@@ -140,7 +137,7 @@ internal object EnumValueOf : IntrinsicBase() {
 
     override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
         val enumEntry = getEnumEntryByName(irFunction, environment) ?: return emptyList()
-        return listOf(customEvaluateInstruction(irFunction, environment), SimpleInstruction(enumEntry))
+        return super.unwind(irFunction, environment) + SimpleInstruction(enumEntry)
     }
 
     override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {
@@ -158,7 +155,7 @@ internal object EnumIntrinsics : IntrinsicBase() {
 
     fun canHandleFunctionWithName(fqName: String, origin: IrDeclarationOrigin): Boolean {
         if (origin == IrDeclarationOrigin.ENUM_CLASS_SPECIAL_MEMBER) return true
-        return fqName.startsWith("kotlin.Enum.")
+        return fqName.startsWith("kotlin.Enum.") && fqName != "kotlin.Enum.<init>"
     }
 
     override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
@@ -229,9 +226,9 @@ internal object ArrayConstructor : IntrinsicBase() {
     }
 
     override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
-        if (irFunction.valueParameters.size == 1) return listOf(customEvaluateInstruction(irFunction, environment))
+        if (irFunction.valueParameters.size == 1) return super.unwind(irFunction, environment)
         val callStack = environment.callStack
-        val instructions = mutableListOf<Instruction>(customEvaluateInstruction(irFunction, environment))
+        val instructions = super.unwind(irFunction, environment).toMutableList()
 
         val sizeSymbol = irFunction.valueParameters[0].symbol
         val size = callStack.loadState(sizeSymbol).asInt()
@@ -298,14 +295,14 @@ internal object AssertIntrinsic : IntrinsicBase() {
     }
 
     override fun unwind(irFunction: IrFunction, environment: IrInterpreterEnvironment): List<Instruction> {
-        if (irFunction.valueParameters.size == 1) return listOf(customEvaluateInstruction(irFunction, environment))
+        if (irFunction.valueParameters.size == 1) return super.unwind(irFunction, environment)
 
         val lambdaParameter = irFunction.valueParameters.last()
         val lambdaState = environment.callStack.loadState(lambdaParameter.symbol) as KFunctionState
         val call = (lambdaState.invokeSymbol.owner as IrSimpleFunction).createCall()
         call.dispatchReceiver = lambdaParameter.createGetValue()
 
-        return listOf(customEvaluateInstruction(irFunction, environment), CompoundInstruction(call))
+        return super.unwind(irFunction, environment) + CompoundInstruction(call)
     }
 
     override fun evaluate(irFunction: IrFunction, environment: IrInterpreterEnvironment) {

compiler/testData/codegen/box/constants/kt53480.kt

@@ -0,0 +1,15 @@
+// TARGET_BACKEND: JVM_IR
+// FILE: J.java
+public class J {
+    public static int f() { return 0; }
+}
+
+// FILE: Main.kt
+enum class A {
+    OK;
+    val x = J.f()
+}
+
+fun box(): String {
+    return A.OK.name
+}

compiler/testData/ir/interpreter/kt53480.kt

@@ -0,0 +1,12 @@
+// FILE: J.java
+public class J {
+    public static int f() { return 0; }
+}
+
+// FILE: Main.kt
+enum class A {
+    E;
+    val x = J.f()
+}
+
+const val name = A.E.name

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

@@ -8133,6 +8133,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/constants/foldingBinaryOpsUnsignedConst.kt");
         }
 
+        @Test
+        @TestMetadata("kt53480.kt")
+        public void testKt53480() throws Exception {
+            runTest("compiler/testData/codegen/box/constants/kt53480.kt");
+        }
+
         @Test
         @TestMetadata("kt9532.kt")
         public void testKt9532() throws Exception {

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ir/interpreter/IrInterpreterAfterFir2IrTestGenerated.java

@@ -205,6 +205,12 @@ public class IrInterpreterAfterFir2IrTestGenerated extends AbstractIrInterpreter
         runTest("compiler/testData/ir/interpreter/interfaceDefault.kt");
     }
 
+    @Test
+    @TestMetadata("kt53480.kt")
+    public void testKt53480() throws Exception {
+        runTest("compiler/testData/ir/interpreter/kt53480.kt");
+    }
+
     @Test
     @TestMetadata("lambda.kt")
     public void testLambda() throws Exception {

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/ir/interpreter/IrInterpreterAfterPsi2IrTestGenerated.java

@@ -205,6 +205,12 @@ public class IrInterpreterAfterPsi2IrTestGenerated extends AbstractIrInterpreter
         runTest("compiler/testData/ir/interpreter/interfaceDefault.kt");
     }
 
+    @Test
+    @TestMetadata("kt53480.kt")
+    public void testKt53480() throws Exception {
+        runTest("compiler/testData/ir/interpreter/kt53480.kt");
+    }
+
     @Test
     @TestMetadata("lambda.kt")
     public void testLambda() throws Exception {