Avoid Iterator allocation in Wasm Backend operations

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

@@ -17,6 +17,7 @@ import org.jetbrains.kotlin.ir.visitors.IrVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 import org.jetbrains.kotlin.js.config.JSConfigurationKeys
+import org.jetbrains.kotlin.utils.indexBasedForEach
 
 fun eliminateDeadDeclarations(modules: List<IrModuleFragment>, context: WasmBackendContext, dceDumpNameCache: DceDumpNameCache) {
     val printReachabilityInfo =
@@ -51,7 +52,7 @@ private fun buildRoots(modules: List<IrModuleFragment>, context: WasmBackendCont
     }
 
     modules.onAllFiles {
-        declarations.forEach { declaration ->
+        declarations.indexBasedForEach { declaration ->
             when (declaration) {
                 is IrFunction -> {
                     if (declaration.isExported()) {
@@ -106,8 +107,8 @@ private fun buildRoots(modules: List<IrModuleFragment>, context: WasmBackendCont
 }
 
 private inline fun List<IrModuleFragment>.onAllFiles(body: IrFile.() -> Unit) {
-    forEach { module ->
-        module.files.forEach { file ->
+    indexBasedForEach { module ->
+        module.files.indexBasedForEach { file ->
             file.body()
         }
     }

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

@@ -17,6 +17,7 @@ import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.util.erasedUpperBound
 import org.jetbrains.kotlin.utils.addToStdlib.firstIsInstanceOrNull
+import org.jetbrains.kotlin.utils.indexBasedForEach
 
 internal class WasmUsefulDeclarationProcessor(
     override val context: WasmBackendContext,
@@ -211,7 +212,7 @@ internal class WasmUsefulDeclarationProcessor(
         val isIntrinsic = irFunction.hasWasmNoOpCastAnnotation() || irFunction.getWasmOpAnnotation() != null
         if (isIntrinsic) return
 
-        irFunction.getEffectiveValueParameters().forEach { it.enqueueValueParameterType(irFunction) }
+        irFunction.getEffectiveValueParameters().indexBasedForEach { it.enqueueValueParameterType(irFunction) }
         irFunction.returnType.enqueueType(irFunction, "function return type")
 
         kotlinClosureToJsClosureConvertFunToKotlinClosureCallFun[irFunction.fileOrNull]?.get(irFunction)?.enqueue(
@@ -236,7 +237,7 @@ internal class WasmUsefulDeclarationProcessor(
 
         // Primitive constructors has no body, since that such constructors implicitly initialize all fields, so we have to preserve them
         if (irConstructor.hasWasmPrimitiveConstructorAnnotation()) {
-            constructedClass.declarations.forEach { declaration ->
+            constructedClass.declarations.indexBasedForEach { declaration ->
                 if (declaration is IrField) {
                     declaration.enqueue(constructedClass, "preserve all fields for primitive constructors")
                 }

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/export/ExportModelGenerator.kt

@@ -16,7 +16,6 @@ import org.jetbrains.kotlin.ir.backend.js.utils.typeScriptInnerClassReference
 import org.jetbrains.kotlin.ir.backend.js.utils.getFqNameWithJsNameWhenAvailable
 import org.jetbrains.kotlin.ir.backend.js.utils.isJsExport
 import org.jetbrains.kotlin.ir.backend.js.utils.realOverrideTarget
-import org.jetbrains.kotlin.ir.backend.js.utils.shouldGenerateObjectWithGetInstanceInEsModuleTypeScript
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrClassifierSymbol
@@ -30,6 +29,7 @@ import org.jetbrains.kotlin.name.parentOrNull
 import org.jetbrains.kotlin.serialization.js.ModuleKind
 import org.jetbrains.kotlin.utils.addToStdlib.runIf
 import org.jetbrains.kotlin.utils.memoryOptimizedFilter
+import org.jetbrains.kotlin.utils.indexBasedForEach
 import org.jetbrains.kotlin.utils.memoryOptimizedMap
 import org.jetbrains.kotlin.utils.memoryOptimizedMapNotNull
 
@@ -60,18 +60,18 @@ class ExportModelGenerator(val context: WasmBackendContext) {
         val declarationVisitor = object : IrVisitorVoid() {
             override fun visitFunction(declaration: IrFunction) {
                 visitType(declaration.returnType)
-                declaration.typeParameters.forEach(::visitTypeParameter)
-                declaration.parameters.forEach {
+                declaration.typeParameters.indexBasedForEach(::visitTypeParameter)
+                declaration.parameters.indexBasedForEach {
                     if (it.kind != IrParameterKind.DispatchReceiver) {
                         visitValueParameter(it)
                     }
                 }
             }
 
             override fun visitClass(declaration: IrClass) {
-                declaration.superTypes.forEach(::visitType)
-                declaration.typeParameters.forEach(::visitTypeParameter)
-                declaration.declarations.forEach { it.acceptVoid(this) }
+                declaration.superTypes.indexBasedForEach(::visitType)
+                declaration.typeParameters.indexBasedForEach(::visitTypeParameter)
+                declaration.declarations.indexBasedForEach { it.acceptVoid(this) }
             }
 
             override fun visitProperty(declaration: IrProperty) {
@@ -88,7 +88,7 @@ class ExportModelGenerator(val context: WasmBackendContext) {
             }
 
             override fun visitTypeParameter(declaration: IrTypeParameter) {
-                declaration.superTypes.forEach(::visitType)
+                declaration.superTypes.indexBasedForEach(::visitType)
             }
 
             private fun visitType(type: IrType) {
@@ -98,7 +98,7 @@ class ExportModelGenerator(val context: WasmBackendContext) {
                 if (!klass.isExternal || klass in excludedFromExport || klass in declarationsToExport) return
                 queue.add(klass)
                 declarationsToExport.add(klass)
-                type.arguments.forEach { it.typeOrNull?.let(::visitType) }
+                type.arguments.indexBasedForEach { it.typeOrNull?.let(::visitType) }
             }
         }
 

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt

@@ -27,6 +27,8 @@ import org.jetbrains.kotlin.ir.util.isNullable
 import org.jetbrains.kotlin.ir.util.isSubtypeOfClass
 import org.jetbrains.kotlin.ir.visitors.IrVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
+import org.jetbrains.kotlin.utils.indexBasedForEach
+import org.jetbrains.kotlin.utils.indexBasedForEachIndexed
 import org.jetbrains.kotlin.wasm.config.WasmConfigurationKeys
 import org.jetbrains.kotlin.wasm.ir.*
 import org.jetbrains.kotlin.wasm.ir.source.location.SourceLocation
@@ -120,7 +122,7 @@ class BodyGenerator(
     }
 
     private fun tryGenerateVarargArray(irVararg: IrVararg, wasmArrayType: WasmImmediate.GcType) {
-        irVararg.elements.forEach {
+        irVararg.elements.indexBasedForEach {
             check(it is IrExpression)
             generateExpression(it)
         }
@@ -331,7 +333,7 @@ class BodyGenerator(
     private fun buildFinallyBody(catchBlock: IrCatch) {
         val composite = catchBlock.result as IrComposite
         assert(composite.statements.last().isSimpleRethrowing(catchBlock)) { "Last throw is not rethrowing" }
-        composite.statements.dropLast(1).forEach(::generateStatement)
+        composite.statements.dropLast(1).indexBasedForEach(::generateStatement)
     }
 
     private fun buildCatchBlockBody(catchBlock: IrCatch) {
@@ -686,7 +688,7 @@ class BodyGenerator(
             body.buildIf("this_init")
             generateAnyParameters(parentClass.symbol, location)
             val irFields: List<IrField> = parentClass.allFields(backendContext.irBuiltIns)
-            irFields.forEachIndexed { index, field ->
+            irFields.indexBasedForEachIndexed { index, field ->
                 if (index > 0) {
                     generateDefaultInitializerForType(wasmModuleTypeTransformer.transformType(field.type), body)
                 }
@@ -1216,7 +1218,7 @@ class BodyGenerator(
     }
 
     override fun visitBlockBody(body: IrBlockBody) {
-        body.statements.forEach(::generateStatement)
+        body.statements.indexBasedForEach(::generateStatement)
         this.body.buildNop(body.getSourceEndLocation())
     }
 
@@ -1244,7 +1246,7 @@ class BodyGenerator(
 
     private fun processContainerExpression(expression: IrContainerExpression) {
         val statements = expression.statements
-        statements.forEachIndexed { i, statement ->
+        statements.indexBasedForEachIndexed { i, statement ->
             if (i != statements.lastIndex) {
                 generateStatement(statement)
             } else {

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/ConstantData.kt

@@ -5,6 +5,8 @@
 
 package org.jetbrains.kotlin.backend.wasm.ir2wasm
 
+import org.jetbrains.kotlin.utils.indexBasedForEach
+import org.jetbrains.kotlin.utils.indexBasedForEachIndexed
 import org.jetbrains.kotlin.wasm.ir.WasmSymbol
 
 // Representation of constant data in Wasm memory
@@ -87,7 +89,7 @@ class ConstantDataCharArray(val value: List<WasmSymbol<Char>>, val fitsLatin1: B
 
     override fun toBytes(): ByteArray {
         return ByteArray(value.size * bytesPerChar).apply {
-            value.forEachIndexed { index, symbol -> symbol.owner.toLittleEndianBytes(this, index * bytesPerChar, fitsLatin1) }
+            value.indexBasedForEachIndexed { index, symbol -> symbol.owner.toLittleEndianBytes(this, index * bytesPerChar, fitsLatin1) }
         }
     }
 
@@ -105,7 +107,7 @@ class ConstantDataCharArray(val value: List<WasmSymbol<Char>>, val fitsLatin1: B
 class ConstantDataStruct(val elements: List<ConstantDataElement>) : ConstantDataElement() {
     override fun toBytes(): ByteArray {
         return buildList {
-            elements.forEach {
+            elements.indexBasedForEach {
                 for (byte in it.toBytes()) {
                     add(byte)
                 }

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/DeclarationGenerator.kt

@@ -26,6 +26,7 @@ import org.jetbrains.kotlin.ir.util.erasedUpperBound
 import org.jetbrains.kotlin.ir.visitors.IrVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 import org.jetbrains.kotlin.name.parentOrNull
+import org.jetbrains.kotlin.utils.indexBasedForEachIndexed
 import org.jetbrains.kotlin.wasm.ir.*
 import org.jetbrains.kotlin.wasm.ir.source.location.SourceLocation
 
@@ -324,7 +325,7 @@ class DeclarationGenerator(
         val initVTableGlobal = buildWasmExpression {
             val location = SourceLocation.NoLocation("Create instance of vtable struct")
             buildSpecialITableInit(metadata, this, location)
-            metadata.virtualMethods.forEachIndexed { i, method ->
+            metadata.virtualMethods.indexBasedForEachIndexed { i, method ->
                 if (method.function.modality != Modality.ABSTRACT) {
                     buildInstr(WasmOp.REF_FUNC, location, WasmImmediate.FuncIdx(wasmFileCodegenContext.referenceFunction(method.function.symbol)))
                 } else {

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/RecursiveTypesUtils.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.backend.wasm.ir2wasm
 
 import org.jetbrains.kotlin.backend.common.serialization.Hash128Bits
 import org.jetbrains.kotlin.backend.wasm.utils.StronglyConnectedComponents
+import org.jetbrains.kotlin.utils.indexBasedForEach
 import org.jetbrains.kotlin.utils.yieldIfNotNull
 import org.jetbrains.kotlin.wasm.ir.*
 
@@ -56,11 +57,11 @@ private fun wasmTypeDeclarationOrderKey(declaration: WasmTypeDeclaration): Int {
 
 fun createRecursiveTypeGroups(types: List<WasmTypeDeclaration>): List<RecursiveTypeGroup> {
     val componentFinder = StronglyConnectedComponents(::dependencyTypes)
-    types.forEach(componentFinder::visit)
+    types.indexBasedForEach(componentFinder::visit)
 
     val components = componentFinder.findComponents()
 
-    components.forEach { component ->
+    components.indexBasedForEach { component ->
         component.sortBy(::wasmTypeDeclarationOrderKey)
     }