[K/Wasm] Refactor the fix for the non-capturing lambda singletons

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsMapping.kt

@@ -26,7 +26,6 @@ class JsMapping : DefaultMapping() {
     val secondaryConstructorToFactory = DefaultDelegateFactory.newDeclarationToDeclarationMapping<IrConstructor, IrSimpleFunction>()
     val objectToGetInstanceFunction = DefaultDelegateFactory.newDeclarationToDeclarationMapping<IrClass, IrSimpleFunction>()
     val objectToInstanceField = DefaultDelegateFactory.newDeclarationToDeclarationMapping<IrClass, IrField>()
-    val functionToInstanceField = DefaultDelegateFactory.newDeclarationToDeclarationMapping<IrClass, IrField>()
     val classToSyntheticPrimaryConstructor = DefaultDelegateFactory.newDeclarationToDeclarationMapping<IrClass, IrConstructor>()
     val privateMemberToCorrespondingStatic = DefaultDelegateFactory.newDeclarationToDeclarationMapping<IrFunction, IrSimpleFunction>()
 

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/WasmLoweringPhases.kt

@@ -475,12 +475,6 @@ private val wasmVarargExpressionLoweringPhase = makeIrModulePhase(
     description = "Lower varargs"
 )
 
-private val fieldInitializersLoweringPhase = makeIrModulePhase(
-    ::FieldInitializersLowering,
-    name = "FieldInitializersLowering",
-    description = "Move field initializers to start function"
-)
-
 private val builtInsLoweringPhase0 = makeIrModulePhase(
     ::BuiltInsLowering,
     name = "BuiltInsLowering0",
@@ -505,7 +499,7 @@ private val objectDeclarationLoweringPhase = makeIrModulePhase(
     ::ObjectDeclarationLowering,
     name = "ObjectDeclarationLowering",
     description = "Create lazy object instance generator functions",
-    prerequisite = setOf(enumClassCreateInitializerLoweringPhase)
+    prerequisite = setOf(enumClassCreateInitializerLoweringPhase, staticCallableReferenceLoweringPhase)
 )
 
 private val objectUsageLoweringPhase = makeIrModulePhase(
@@ -606,6 +600,13 @@ private val inlineObjectsWithPureInitializationLoweringPhase = makeIrModulePhase
     prerequisite = setOf(purifyObjectInstanceGettersLoweringPhase)
 )
 
+private val fieldInitializersLoweringPhase = makeIrModulePhase(
+    ::FieldInitializersLowering,
+    name = "FieldInitializersLowering",
+    description = "Move field initializers to start function",
+    prerequisite = setOf(purifyObjectInstanceGettersLoweringPhase)
+)
+
 val constEvaluationPhase = makeIrModulePhase(
     { context ->
         val configuration = IrInterpreterConfiguration(

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/dce/WasmUsefulDeclarationProcessor.kt

@@ -7,7 +7,6 @@ package org.jetbrains.kotlin.backend.wasm.dce
 
 import org.jetbrains.kotlin.backend.wasm.WasmBackendContext
 import org.jetbrains.kotlin.backend.wasm.ir2wasm.*
-import org.jetbrains.kotlin.backend.wasm.lower.isFunctionReferenceInstanceField
 import org.jetbrains.kotlin.backend.wasm.utils.*
 import org.jetbrains.kotlin.ir.backend.js.dce.UsefulDeclarationProcessor
 import org.jetbrains.kotlin.ir.backend.js.utils.*
@@ -49,7 +48,7 @@ internal class WasmUsefulDeclarationProcessor(
         }
 
         override fun visitSetField(expression: IrSetField, data: IrDeclaration) {
-            if (!expression.symbol.owner.run { isObjectInstanceField() || isFunctionReferenceInstanceField() }) {
+            if (!expression.symbol.owner.isObjectInstanceField()) {
                 super.visitSetField(expression, data)
             }
         }
@@ -57,7 +56,7 @@ internal class WasmUsefulDeclarationProcessor(
         override fun visitGetField(expression: IrGetField, data: IrDeclaration) {
             val field = expression.symbol.owner
 
-            if (field.isObjectInstanceField() || field.isFunctionReferenceInstanceField()) {
+            if (field.isObjectInstanceField()) {
                 field.type.classOrFail.owner.primaryConstructor?.enqueue(field, "object lazy initialization")
             }
 

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/dce/WasmUselessDeclarationsRemover.kt

@@ -6,14 +6,11 @@
 package org.jetbrains.kotlin.backend.wasm.dce
 
 import org.jetbrains.kotlin.backend.wasm.WasmBackendContext
-import org.jetbrains.kotlin.backend.wasm.lower.isFunctionReferenceInstanceField
 import org.jetbrains.kotlin.ir.IrElement
 import org.jetbrains.kotlin.ir.backend.js.utils.isObjectInstanceField
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrBlockBody
 import org.jetbrains.kotlin.ir.expressions.IrSetField
-import org.jetbrains.kotlin.ir.types.classOrFail
-import org.jetbrains.kotlin.ir.util.primaryConstructor
 import org.jetbrains.kotlin.ir.util.transformFlat
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
@@ -57,7 +54,7 @@ class WasmUselessDeclarationsRemover(
 
     private fun IrSimpleFunction.removeUnusedObjectsInitializers() {
         (body as? IrBlockBody)?.statements?.removeIf {
-            it is IrSetField && it.symbol.owner.run { isObjectInstanceField() || isFunctionReferenceInstanceField() } && it.symbol.owner !in usefulDeclarations
+            it is IrSetField && it.symbol.owner.isObjectInstanceField() && it.symbol.owner !in usefulDeclarations
         }
     }
 }

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/lower/FieldInitializersLowering.kt

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.backend.common.lower.at
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
 import org.jetbrains.kotlin.backend.wasm.WasmBackendContext
 import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.backend.js.utils.isObjectInstanceField
 import org.jetbrains.kotlin.ir.builders.irSetField
 import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.declarations.IrFile
@@ -55,9 +56,11 @@ class FieldInitializersLowering(val context: WasmBackendContext) : FileLoweringP
                 }
 
                 val initializerStatement = builder.at(initValue).irSetField(null, declaration, initValue)
+                val statements = startFunctionBody.statements
 
-                when (declaration.fqNameWhenAvailable) {
+                when {
-                    stringPoolFqName -> startFunctionBody.statements.add(0, initializerStatement)
+                    declaration.fqNameWhenAvailable == stringPoolFqName -> statements.add(0, initializerStatement)
+                    declaration.isObjectInstanceField() -> statements.add(if (statements.size >= 1) 1 else 0, initializerStatement)
                     else -> startFunctionBody.statements.add(initializerStatement)
                 }
 

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/lower/WasmStaticCallableReferenceLowering.kt

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.backend.common.getOrPut
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
 import org.jetbrains.kotlin.backend.wasm.WasmBackendContext
 import org.jetbrains.kotlin.backend.wasm.lower.WasmPropertyReferenceLowering.Companion.DECLARATION_ORIGIN_KPROPERTIES_FOR_DELEGATION
+import org.jetbrains.kotlin.descriptors.ClassKind
 import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
 import org.jetbrains.kotlin.ir.IrStatement
 import org.jetbrains.kotlin.ir.backend.js.lower.CallableReferenceLowering.Companion.FUNCTION_REFERENCE_IMPL
@@ -21,6 +22,7 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.IrConstructorCall
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.impl.IrGetFieldImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrGetObjectValueImpl
 import org.jetbrains.kotlin.ir.types.makeNullable
 import org.jetbrains.kotlin.ir.util.constructedClass
 import org.jetbrains.kotlin.ir.util.defaultType
@@ -31,20 +33,11 @@ import org.jetbrains.kotlin.name.Name
 
 class WasmStaticCallableReferenceLowering(val context: WasmBackendContext) : FileLoweringPass {
     override fun lower(irFile: IrFile) {
-        val irFields = mutableSetOf<IrField>()
-        val firstKProperty = irFile.declarations.indexOfFirst { it.origin == DECLARATION_ORIGIN_KPROPERTIES_FOR_DELEGATION }
-
         irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
             override fun visitClass(declaration: IrClass): IrStatement {
                 declaration.transformChildrenVoid()
                 if (declaration.isSyntheticSingleton) {
-                    val functionReferenceField = declaration.getOrCreateInstanceField().apply {
+                    declaration.kind = ClassKind.OBJECT
-                        parent = irFile
-                        initializer = context.createIrBuilder(symbol).run {
-                            irExprBody(irCall(declaration.primaryConstructor!!))
-                        }
-                    }
-                    irFields.add(functionReferenceField)
                 }
                 return declaration
             }
@@ -54,39 +47,10 @@ class WasmStaticCallableReferenceLowering(val context: WasmBackendContext) : Fil
                 if (!constructedClass.isSyntheticSingleton)
                     return super.visitConstructorCall(expression)
 
-                val instanceField = constructedClass.getOrCreateInstanceField()
+                return IrGetObjectValueImpl(expression.startOffset, expression.endOffset, expression.type, constructedClass.symbol)
-                return IrGetFieldImpl(expression.startOffset, expression.endOffset, instanceField.symbol, expression.type)
             }
         })
-
-        // Should be placed before KProperty initializations
-        if (firstKProperty != -1) {
-            irFile.declarations.addAll(firstKProperty, irFields)
-        } else {
-            irFile.declarations.addAll(irFields)
-        }
     }
-
-
-    private fun IrClass.getOrCreateInstanceField(): IrField = context.mapping.functionToInstanceField.getOrPut(this) {
-        val klass = this
-        context.irFactory.buildField {
-            name = Name.identifier(klass.name.asString() + "_instance")
-            type = klass.defaultType.makeNullable()
-            isStatic = true
-            isFinal = true
-            origin = FUNCTION_REFERENCE_SINGLETON_FIELD
-            visibility = DescriptorVisibilities.PRIVATE
-        }.apply {
-            initializer = null
-        }
-    }
-}
-
-val FUNCTION_REFERENCE_SINGLETON_FIELD by IrDeclarationOriginImpl
-
-fun IrField.isFunctionReferenceInstanceField(): Boolean {
-    return origin == FUNCTION_REFERENCE_SINGLETON_FIELD
 }
 
 val IrClass.isSyntheticSingleton: Boolean

compiler/testData/debug/stepping/anonymousFunction.kt

@@ -25,7 +25,7 @@ fun box() {
 
 // EXPECTATIONS WASM
 // test.kt:1 $box
-// test.kt:7 $box (9, 4)
+// test.kt:7 $box
 // test.kt:4 $eval (27, 30)
 // test.kt:8 $box$lambda.invoke (9, 9, 9, 9)
 // String.kt:141 $kotlin.stringLiteral (17, 28, 17)

compiler/testData/debug/stepping/dataClass.kt

@@ -248,7 +248,7 @@ fun box() {
 // Number2String.kt:61 $kotlin.wasm.internal.utoa32 (28, 14)
 // Number2String.kt:63 $kotlin.wasm.internal.utoa32 (18, 23, 35, 4)
 // Number2String.kt:69 $kotlin.wasm.internal.utoaDecSimple (11, 23, 11, 11, 4)
-// Assertions.kt:14 $kotlin.assert (11, 18, 4, 11, 18, 4, 11, 18, 4, 11, 18, 4)
+// Assertions.kt:14 $kotlin.assert (11, 4, 11, 4, 11, 4, 11, 4)
 // Assertions.kt:21 $kotlin.assert (9, 8, 9, 8, 9, 8, 9, 8)
 // Assertions.kt:25 $kotlin.assert (1, 1, 1, 1)
 // Assertions.kt:15 $kotlin.assert (1, 1, 1, 1)

compiler/testData/debug/stepping/functionCallWithLambdaParam.kt

@@ -45,10 +45,10 @@ fun foo(f: () -> Unit) {
 
 // EXPECTATIONS WASM
 // test.kt:1 $box
-// test.kt:5 $box (8, 4)
+// test.kt:5 $box
 // test.kt:15 $foo (4, 4)
 // test.kt:6 $box$lambda.invoke (20, 12, 21)
 // test.kt:16 $foo (1, 1)
-// test.kt:9 $box (10, 4)
+// test.kt:9 $box
 // test.kt:10 $box$lambda.invoke (16, 8, 17)
 // test.kt:12 $box

compiler/testData/debug/stepping/kt42208.kt

@@ -27,7 +27,6 @@ inline fun foo() = {
 // EXPECTATIONS WASM
 // test.kt:1 $box
 // test.kt:6 $box (4, 4)
-// test1.kt:10 $box
 // test1.kt:11 $box
 // test.kt:8 $box$lambda.invoke
 // test.kt:7 $box

compiler/testData/debug/stepping/kt42208b.kt

@@ -30,7 +30,6 @@ inline fun foo() = {
 // EXPECTATIONS WASM
 // test.kt:1 $box
 // test.kt:6 $box
-// test1.kt:11 $box
 // test1.kt:12 $box
 // test.kt:7 $box
 // test.kt:9 $box$lambda.invoke

compiler/testData/debug/stepping/kt42208c.kt

@@ -52,7 +52,6 @@ fun baz(v:(() -> Unit)) {
 // EXPECTATIONS WASM
 // test.kt:1 $box
 // test.kt:6 $box (8, 4)
-// test1.kt:12 $box (19, 19)
 // test1.kt:13 $box (1, 1)
 // test3.kt:16 $baz (4, 4)
 // test.kt:10 $box$lambda.invoke

compiler/testData/debug/stepping/namedCallableReference.kt

@@ -35,7 +35,7 @@ fun g() {}
 // EXPECTATIONS WASM
 // test.kt:1 $box
 // test.kt:4 $box (12, 4)
-// test.kt:5 $box (6, 4)
+// test.kt:5 $box
 // test.kt:9 $f
 // test.kt:12 $g
 // test.kt:10 $f

compiler/testData/debug/stepping/variablesWithoutInitializer.kt

@@ -68,7 +68,7 @@ fun box() {
 // Number2String.kt:61 $kotlin.wasm.internal.utoa32 (28, 14)
 // Number2String.kt:63 $kotlin.wasm.internal.utoa32 (18, 23, 35, 4)
 // Number2String.kt:69 $kotlin.wasm.internal.utoaDecSimple (11, 23, 11, 11, 4)
-// Assertions.kt:14 $kotlin.assert (11, 18, 4, 11, 18, 4, 11, 18, 4, 11, 18, 4, 11, 18, 4)
+// Assertions.kt:14 $kotlin.assert (11, 4, 11, 4, 11, 4, 11, 4, 11, 4)
 // Assertions.kt:21 $kotlin.assert (9, 8, 9, 8, 9, 8, 9, 8, 9, 8)
 // Assertions.kt:25 $kotlin.assert (1, 1, 1, 1, 1)
 // Assertions.kt:15 $kotlin.assert (1, 1, 1, 1, 1)