[IR] Rename MFVC tests + Add test for get-field optimization

#KT-1179

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

@@ -50202,9 +50202,9 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
         }
 
         @Test
-        @TestMetadata("MfvcFieldInitializationOrder.kt")
+        @TestMetadata("mfvcFieldInitializationOrder.kt")
         public void testMfvcFieldInitializationOrder() throws Exception {
-            runTest("compiler/testData/codegen/box/valueClasses/MfvcFieldInitializationOrder.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
+            runTest("compiler/testData/codegen/box/valueClasses/mfvcFieldInitializationOrder.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
         }
 
         @Test

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

@@ -5796,15 +5796,15 @@ public class FirBytecodeTextTestGenerated extends AbstractFirBytecodeTextTest {
         }
 
         @Test
-        @TestMetadata("MFVCDeclaration.kt")
+        @TestMetadata("mfvcDeclaration.kt")
-        public void testMFVCDeclaration() throws Exception {
+        public void testMfvcDeclaration() throws Exception {
-            runTest("compiler/testData/codegen/bytecodeText/valueClasses/MFVCDeclaration.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
+            runTest("compiler/testData/codegen/bytecodeText/valueClasses/mfvcDeclaration.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
         }
 
         @Test
-        @TestMetadata("MFVCReassignments.kt")
+        @TestMetadata("mfvcReassignments.kt")
-        public void testMFVCReassignments() throws Exception {
+        public void testMfvcReassignments() throws Exception {
-            runTest("compiler/testData/codegen/bytecodeText/valueClasses/MFVCReassignments.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
+            runTest("compiler/testData/codegen/bytecodeText/valueClasses/mfvcReassignments.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
         }
 
         @Test

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

@@ -692,7 +692,7 @@ internal class BridgeLowering(val context: JvmBackendContext) : FileLoweringPass
                                 val instance = targetRemappedParameter.rootMfvcNode.createInstanceFromBox(
                                     this@irBlock,
                                     irCastIfNeeded(irGet(bridgeParameter), targetParameterType),
-                                    hasAccessToPrivateMembersOf(target, targetRemappedParameter.rootMfvcNode.mfvc)
+                                    getOptimizedPublicAccess(target, targetRemappedParameter.rootMfvcNode.mfvc)
                                 ) { error("Not applicable") }
                                 val newArguments = instance.makeFlattenedGetterExpressions()
                                 for (newArgument in newArguments) {

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

@@ -131,7 +131,7 @@ private class JvmMultiFieldValueClassLowering(context: JvmBackendContext) : JvmV
             val typeArguments = makeTypeArgumentsFromField(expression)
             var instance: ReceiverBasedMfvcNodeInstance? = null
             return scope.irBlock {
-                instance = node.createInstanceFromBox(this, typeArguments, expression.receiver, true, ::variablesSaver)
+                instance = node.createInstanceFromBox(this, typeArguments, expression.receiver, AccessType.AlwaysPrivate, ::variablesSaver)
                 +instance!!.makeGetterExpression()
             }.also { expression2MfvcNodeInstanceAccessor[it] = MfvcNodeInstanceAccessor.Getter(instance!!) }
         }
@@ -144,7 +144,7 @@ private class JvmMultiFieldValueClassLowering(context: JvmBackendContext) : JvmV
             var instance: ReceiverBasedMfvcNodeInstance? = null
             var values: List<IrExpression>? = null
             return scope.irBlock {
-                instance = node.createInstanceFromBox(this, typeArguments, expression.receiver, true, ::variablesSaver)
+                instance = node.createInstanceFromBox(this, typeArguments, expression.receiver, AccessType.AlwaysPrivate, ::variablesSaver)
                 values = makeFlattenedExpressionsWithGivenSafety(node, safe, expression.value)
                 instance!!.addSetterStatements(this, values!!)
             }.also { expression2MfvcNodeInstanceAccessor[it] = MfvcNodeInstanceAccessor.Setter(instance!!, values!!) }
@@ -153,12 +153,19 @@ private class JvmMultiFieldValueClassLowering(context: JvmBackendContext) : JvmV
         fun makeReplacement(scope: IrBuilderWithScope, expression: IrCall): IrExpression? {
             val function = expression.symbol.owner
             val property = function.property?.takeIf { function.isGetter } ?: return null
-            expression.dispatchReceiver?.get(property.name)?.let { return it }
+            val dispatchReceiver = expression.dispatchReceiver
+            dispatchReceiver?.get(property.name)?.let { return it }
             val node = replacements.getMfvcPropertyNode(property) ?: return null
             val typeArguments = makeTypeArgumentsFromFunction(expression)
             var instance: ReceiverBasedMfvcNodeInstance? = null
             return scope.irBlock {
-                instance = node.createInstanceFromBox(this, typeArguments, expression.dispatchReceiver, false, ::variablesSaver)
+                // Optimization: pure function access to leaf can be replaced with field access if the field itself is accessible
+                val accessType = when {
+                    !node.hasPureUnboxMethod -> AccessType.AlwaysPublic
+                    dispatchReceiver == null -> AccessType.PrivateWhenNoBox
+                    else -> getOptimizedPublicAccess(dispatchReceiver.type.erasedUpperBound)
+                }
+                instance = node.createInstanceFromBox(this, typeArguments, dispatchReceiver, accessType, ::variablesSaver)
                 +instance!!.makeGetterExpression()
             }.also { expression2MfvcNodeInstanceAccessor[it] = MfvcNodeInstanceAccessor.Getter(instance!!) }
         }
@@ -502,7 +509,7 @@ private class JvmMultiFieldValueClassLowering(context: JvmBackendContext) : JvmV
                                     val receiver = sourceExplicitParameters[flattenedSourceIndex++]
                                     val rootNode = remappedTargetParameter.rootMfvcNode
                                     val instance = rootNode.createInstanceFromBox(
-                                        this@irBlock, irGet(receiver), hasAccessToPrivateMembersOf(rootNode.mfvc), ::variablesSaver
+                                        this@irBlock, irGet(receiver), getOptimizedPublicAccess(rootNode.mfvc), ::variablesSaver,
                                     )
                                     val flattenedExpressions = instance.makeFlattenedGetterExpressions()
                                     for (expression in flattenedExpressions) {
@@ -982,17 +989,14 @@ private class JvmMultiFieldValueClassLowering(context: JvmBackendContext) : JvmV
             }
         }
         val expressionInstance = flattenedExpressionInstance ?: rootNode.createInstanceFromBox(
-            this,
+            this, transformedExpression, getOptimizedPublicAccess(rootNode.mfvc), ::variablesSaver,
-            transformedExpression,
-            hasAccessToPrivateMembersOf(rootNode.mfvc),
-            ::variablesSaver,
         )
         require(expressionInstance.size == instance.size) { "Incompatible assignment sizes: ${expressionInstance.size}, ${instance.size}" }
         instance.addSetterStatements(this, expressionInstance.makeFlattenedGetterExpressions())
     }
 
-    private fun hasAccessToPrivateMembersOf(parent: IrClass): Boolean =
+    private fun getOptimizedPublicAccess(parent: IrClass): AccessType =
-        currentScope?.irElement?.let { hasAccessToPrivateMembersOf(it, parent) } == true
+        currentScope?.irElement?.let { getOptimizedPublicAccess(it, parent) } ?: AccessType.AlwaysPublic
 
     /**
      * Removes boxing when the result is not used
@@ -1123,7 +1127,7 @@ private fun IrStatement.containsUsagesOf(variablesSet: Set<IrVariable>): Boolean
 }
 
 /**
- * Adds declrations of the variables to the most narrow possible block or body.
+ * Adds declarations of the variables to the most narrow possible block or body.
  * It adds them before the first usage within the block and inlines initialization of them when possible.
  */
 fun IrBody.makeBodyWithAddedVariables(

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

@@ -33,7 +33,7 @@ sealed interface MfvcNode {
         scope: IrBlockBuilder,
         typeArguments: TypeArguments,
         receiver: IrExpression?,
-        isPrivateAccess: Boolean,
+        accessType: AccessType,
         saveVariable: (IrVariable) -> Unit,
     ): ReceiverBasedMfvcNodeInstance
 }
@@ -41,10 +41,10 @@ sealed interface MfvcNode {
 fun MfvcNode.createInstanceFromBox(
     scope: IrBlockBuilder,
     receiver: IrExpression,
-    isPrivateAccess: Boolean,
+    accessType: AccessType,
     saveVariable: (IrVariable) -> Unit
 ) =
-    createInstanceFromBox(scope, makeTypeArgumentsFromType(receiver.type as IrSimpleType), receiver, isPrivateAccess, saveVariable)
+    createInstanceFromBox(scope, makeTypeArgumentsFromType(receiver.type as IrSimpleType), receiver, accessType, saveVariable)
 
 fun MfvcNode.createInstanceFromValueDeclarationsAndBoxType(
     scope: IrBuilderWithScope, type: IrSimpleType, name: Name, saveVariable: (IrVariable) -> Unit,
@@ -314,10 +314,10 @@ class LeafMfvcNode(
         scope: IrBlockBuilder,
         typeArguments: TypeArguments,
         receiver: IrExpression?,
-        isPrivateAccess: Boolean,
+        accessType: AccessType,
         saveVariable: (IrVariable) -> Unit,
     ) = ReceiverBasedMfvcNodeInstance(
-        scope, this, typeArguments, receiver, field?.let(::listOf), unboxMethod, isPrivateAccess, saveVariable
+        scope, this, typeArguments, receiver, field?.let(::listOf), unboxMethod, accessType, saveVariable
     )
 
     override fun toString(): String = "$fullFieldName: ${type.render()}"
@@ -364,10 +364,10 @@ class IntermediateMfvcNode(
         scope: IrBlockBuilder,
         typeArguments: TypeArguments,
         receiver: IrExpression?,
-        isPrivateAccess: Boolean,
+        accessType: AccessType,
         saveVariable: (IrVariable) -> Unit,
     ) = ReceiverBasedMfvcNodeInstance(
-        scope, this, typeArguments, receiver, fields, unboxMethod, isPrivateAccess, saveVariable
+        scope, this, typeArguments, receiver, fields, unboxMethod, accessType, saveVariable
     )
 
     override fun toString(): String =
@@ -460,9 +460,9 @@ class RootMfvcNode internal constructor(
         scope: IrBlockBuilder,
         typeArguments: TypeArguments,
         receiver: IrExpression?,
-        isPrivateAccess: Boolean,
+        accessType: AccessType,
         saveVariable: (IrVariable) -> Unit,
-    ) = ReceiverBasedMfvcNodeInstance(scope, this, typeArguments, receiver, fields, null, isPrivateAccess, saveVariable)
+    ) = ReceiverBasedMfvcNodeInstance(scope, this, typeArguments, receiver, fields, null, accessType, saveVariable)
 
     override fun toString(): String =
         "${type.render()}\n${subnodes.joinToString("\n").prependIndent("    ")}"

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

@@ -471,16 +471,17 @@ private fun getOverriddenNode(replacements: MemoizedMultiFieldValueClassReplacem
         .firstOrNull { !it.owner.isFakeOverride }
         ?.let { replacements.getMfvcPropertyNode(it.owner.correspondingPropertySymbol!!.owner) }
 
-fun hasAccessToPrivateMembersOf(currentElement: IrElement?, parent: IrClass): Boolean {
+fun getOptimizedPublicAccess(currentElement: IrElement?, parent: IrClass): AccessType {
-    val declaration = currentElement as? IrDeclaration ?: return false
+    val declaration = currentElement as? IrDeclaration ?: return AccessType.AlwaysPublic
     for (cur in declaration.parents.filterIsInstance<IrClass>()) {
         return when {
-            cur == parent -> true
+            cur == parent -> AccessType.PrivateWhenNoBox
             cur.isInner -> continue
-            else -> false
+            cur.isCompanion -> continue
+            else -> AccessType.AlwaysPublic
         }
     }
-    return false
+    return AccessType.AlwaysPublic
 }
 
 private fun IrProperty.getterIfDeclared(parent: IrDeclarationContainer): IrSimpleFunction? = getter?.takeIf { it in parent.declarations }

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

@@ -142,6 +142,8 @@ fun IrExpression?.isRepeatableSetter(): Boolean = when (this) {
 
 fun IrExpression?.isRepeatableAccessor(): Boolean = isRepeatableGetter() || isRepeatableSetter()
 
+enum class AccessType { AlwaysPublic, PrivateWhenNoBox, AlwaysPrivate }
+
 class ReceiverBasedMfvcNodeInstance(
     override val scope: IrBlockBuilder,
     override val node: MfvcNode,
@@ -149,7 +151,7 @@ class ReceiverBasedMfvcNodeInstance(
     receiver: IrExpression?,
     val fields: List<IrField>?,
     val unboxMethod: IrSimpleFunction?,
-    val isPrivateAccess: Boolean,
+    val accessType: AccessType,
     private val saveVariable: (IrVariable) -> Unit,
 ) : MfvcNodeInstance {
     override val type: IrSimpleType = makeTypeFromMfvcNodeAndTypeArguments(node, typeArguments)
@@ -169,7 +171,9 @@ class ReceiverBasedMfvcNodeInstance(
     override fun makeFlattenedGetterExpressions(): List<IrExpression> = when (node) {
         is LeafMfvcNode -> listOf(makeGetterExpression())
         is MfvcNodeWithSubnodes -> when {
-            node is IntermediateMfvcNode && isPrivateAccess && fields != null -> fields.map { scope.irGetField(makeReceiverCopy(), it) }
+            node is IntermediateMfvcNode && canUsePrivateAccessFor(node) && fields != null ->
+                fields.map { scope.irGetField(makeReceiverCopy(), it) }
+
             node is IntermediateMfvcNode && !node.hasPureUnboxMethod -> {
                 val value = makeGetterExpression()
                 val asVariable = scope.savableStandaloneVariableWithSetter(
@@ -180,7 +184,7 @@ class ReceiverBasedMfvcNodeInstance(
                 )
                 val root = node.rootNode
                 val variableInstance =
-                    root.createInstanceFromBox(scope, typeArguments, scope.irGet(asVariable), isPrivateAccess = false, saveVariable)
+                    root.createInstanceFromBox(scope, typeArguments, scope.irGet(asVariable), accessType, saveVariable)
                 variableInstance.makeFlattenedGetterExpressions()
             }
 
@@ -190,8 +194,8 @@ class ReceiverBasedMfvcNodeInstance(
 
     override fun makeGetterExpression(): IrExpression = with(scope) {
         when {
-            node is LeafMfvcNode && isPrivateAccess && fields != null -> irGetField(makeReceiverCopy(), fields.single())
+            node is LeafMfvcNode && canUsePrivateAccessFor(node) && fields != null -> irGetField(makeReceiverCopy(), fields.single())
-            node is IntermediateMfvcNode && isPrivateAccess && fields != null -> node.makeBoxedExpression(
+            node is IntermediateMfvcNode && accessType == AccessType.AlwaysPrivate && fields != null -> node.makeBoxedExpression(
                 this, typeArguments, fields.map { irGetField(makeReceiverCopy(), it) }
             )
             unboxMethod != null -> irCall(unboxMethod).apply {
@@ -210,9 +214,12 @@ class ReceiverBasedMfvcNodeInstance(
         }
     }
 
+    private fun canUsePrivateAccessFor(node: NameableMfvcNode) =
+        node.hasPureUnboxMethod && accessType == AccessType.PrivateWhenNoBox || accessType == AccessType.AlwaysPrivate
+
     override fun get(name: Name): ReceiverBasedMfvcNodeInstance? {
         val (newNode, _) = node.getSubnodeAndIndices(name) ?: return null
-        return newNode.createInstanceFromBox(scope, typeArguments, makeReceiverCopy(), isPrivateAccess, saveVariable)
+        return newNode.createInstanceFromBox(scope, typeArguments, makeReceiverCopy(), accessType, saveVariable)
     }
 
     override fun makeStatements(values: List<IrExpression>): List<IrStatement> {

compiler/testData/codegen/box/valueClasses/mfvcFieldInitializationOrder.txt

@@ -1,6 +1,6 @@
 @kotlin.Metadata
 public final class A {
-    // source: 'MfvcFieldInitializationOrder.kt'
+    // source: 'mfvcFieldInitializationOrder.kt'
     private field x-0: double
     private field x-1: double
     public method <init>(p0: double, p1: double): void
@@ -12,7 +12,7 @@ public final class A {
 
 @kotlin.Metadata
 public final class B {
-    // source: 'MfvcFieldInitializationOrder.kt'
+    // source: 'mfvcFieldInitializationOrder.kt'
     private field a-0: double
     private field a-1: double
     private final field b-0: double
@@ -35,7 +35,7 @@ public final class B {
 @kotlin.jvm.JvmInline
 @kotlin.Metadata
 public final class DPoint {
-    // source: 'MfvcFieldInitializationOrder.kt'
+    // source: 'mfvcFieldInitializationOrder.kt'
     private final field field-0: double
     private final field field-1: double
     private synthetic method <init>(p0: double, p1: double): void
@@ -56,6 +56,6 @@ public final class DPoint {
 
 @kotlin.Metadata
 public final class MfvcFieldInitializationOrderKt {
-    // source: 'MfvcFieldInitializationOrder.kt'
+    // source: 'mfvcFieldInitializationOrder.kt'
     public final static @org.jetbrains.annotations.NotNull method box(): java.lang.String
 }

compiler/testData/codegen/bytecodeText/valueClasses/mfvcDeclaration.kt

@@ -22,6 +22,14 @@ value class D(val x: C) {
     }
 }
 
+class Regular(private val x: D) {
+    fun privateAccess() {
+        listOf(x.x.x)
+        listOf(x.x)
+        listOf(x)
+    }
+}
+
 fun functionWithoutBoxes(x: D, y: D) {
     var z: D = x
     val t: D = D(C(1, B(3U), "4"))
@@ -61,7 +69,8 @@ fun functionWithoutBoxes(x: D, y: D) {
 // 1 private final Ljava/lang/String; field-2\n
 // 1 INVOKESPECIAL C.<init> \(IILjava/lang/String;\)V
 // 1 INVOKESPECIAL D.<init> \(IILjava/lang/String;\)V
-// 1 INVOKESTATIC D.box-impl \(IILjava/lang/String;\)LD;
+// 2 INVOKESTATIC D.box-impl \(IILjava/lang/String;\)LD;
-// 2 INVOKESTATIC C.box-impl \(IILjava/lang/String;\)LC;
+// 3 INVOKESTATIC C.box-impl \(IILjava/lang/String;\)LC;
 // 1 public final static functionWithoutBoxes-GPBa7dw\(IILjava/lang/String;IILjava/lang/String;\)V
 // 0 functionWithoutBoxes.*(\n {3}.*)*(\n {4}(NEW [ABCD]|.*(box|[ABCD]\.<init>|LA;|LB;|LC;|LD;)))
+// 1 privateAccess.*(\n   .+)*(\n    GETFIELD Regular\.x-0-0 : I)(\n   .+)*(\n    INVOKEVIRTUAL Regular\.getX-0 \(\)LC;)(\n   .+)*(\n    INVOKESPECIAL Regular\.getX \(\)LD;)

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

@@ -50202,9 +50202,9 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
         }
 
         @Test
-        @TestMetadata("MfvcFieldInitializationOrder.kt")
+        @TestMetadata("mfvcFieldInitializationOrder.kt")
         public void testMfvcFieldInitializationOrder() throws Exception {
-            runTest("compiler/testData/codegen/box/valueClasses/MfvcFieldInitializationOrder.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
+            runTest("compiler/testData/codegen/box/valueClasses/mfvcFieldInitializationOrder.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
         }
 
         @Test

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

@@ -5796,15 +5796,15 @@ public class IrBytecodeTextTestGenerated extends AbstractIrBytecodeTextTest {
         }
 
         @Test
-        @TestMetadata("MFVCDeclaration.kt")
+        @TestMetadata("mfvcDeclaration.kt")
-        public void testMFVCDeclaration() throws Exception {
+        public void testMfvcDeclaration() throws Exception {
-            runTest("compiler/testData/codegen/bytecodeText/valueClasses/MFVCDeclaration.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
+            runTest("compiler/testData/codegen/bytecodeText/valueClasses/mfvcDeclaration.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
         }
 
         @Test
-        @TestMetadata("MFVCReassignments.kt")
+        @TestMetadata("mfvcReassignments.kt")
-        public void testMFVCReassignments() throws Exception {
+        public void testMfvcReassignments() throws Exception {
-            runTest("compiler/testData/codegen/bytecodeText/valueClasses/MFVCReassignments.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
+            runTest("compiler/testData/codegen/bytecodeText/valueClasses/mfvcReassignments.kt", TransformersFunctions.getReplaceOptionalJvmInlineAnnotationWithReal());
         }
 
         @Test