[JS IR BE] Implement primitive companion object

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

@@ -11,6 +11,7 @@ import org.jetbrains.kotlin.backend.common.descriptors.KnownPackageFragmentDescr
 import org.jetbrains.kotlin.backend.common.ir.Ir
 import org.jetbrains.kotlin.backend.common.ir.Symbols
 import org.jetbrains.kotlin.backend.js.JsDescriptorsFactory
+import org.jetbrains.kotlin.builtins.PrimitiveType
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
@@ -107,6 +108,18 @@ class JsIrBackendContext(
         (0..22).map { symbolTable.referenceClass(reflectionTypes.getKFunction(it)) }
     }
 
+    val primitiveCompanionObjects = PrimitiveType.NUMBER_TYPES
+        .filter { it.name != "LONG" && it.name != "CHAR" } // skip due to they have own explicit companions
+        .map {
+            it.typeName to symbolTable.lazyWrapper.referenceClass(
+                getClass(
+                    internalPackageName
+                        .child(Name.identifier("internal"))
+                        .child(Name.identifier("${it.typeName.identifier}CompanionObject"))
+                )
+            )
+        }.toMap()
+
     val suspendFunctions = (0..22).map { symbolTable.referenceClass(builtIns.getSuspendFunction(it)) }
 
     val dynamicType = IrDynamicTypeImpl(createDynamicType(builtIns), emptyList(), Variance.INVARIANT)

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

@@ -116,6 +116,7 @@ private fun JsIrBackendContext.lower(moduleFragment: IrModuleFragment) {
     moduleFragment.files.forEach(clble.getClosureBuilder())
     moduleFragment.files.forEach(clble.getReferenceReplacer())
     moduleFragment.files.forEach(ClassReferenceLowering(this)::lower)
+    moduleFragment.files.forEach(PrimitiveCompanionLowering(this)::lower)
     moduleFragment.files.forEach(IntrinsicifyCallsLowering(this)::lower)
 }
 

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/PrimitiveCompanionLowering.kt

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.ir.backend.js.lower
+
+import org.jetbrains.kotlin.backend.common.FileLoweringPass
+import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
+import org.jetbrains.kotlin.ir.declarations.IrClass
+import org.jetbrains.kotlin.ir.declarations.IrFile
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.IrGetObjectValue
+import org.jetbrains.kotlin.ir.expressions.impl.IrGetObjectValueImpl
+import org.jetbrains.kotlin.ir.types.isPrimitiveType
+import org.jetbrains.kotlin.ir.util.defaultType
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
+import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
+
+class PrimitiveCompanionLowering(val context: JsIrBackendContext) : FileLoweringPass {
+    override fun lower(irFile: IrFile) {
+        irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
+            override fun visitGetObjectValue(expression: IrGetObjectValue): IrExpression {
+                val symbol = expression.symbol
+                if (!symbol.isBound) return expression
+                val declaration = symbol.owner
+                if (!declaration.isCompanion) return expression
+                val parent = declaration.parent as IrClass
+                if (!parent.defaultType.isPrimitiveType()) return expression
+                val actualCompanion = context.primitiveCompanionObjects[parent.name] ?: return expression
+                return expression.run { IrGetObjectValueImpl(startOffset, endOffset, actualCompanion.owner.defaultType, actualCompanion) }
+            }
+        })
+    }
+}

js/js.tests/test/org/jetbrains/kotlin/js/test/BasicIrBoxTest.kt

@@ -24,6 +24,8 @@ private val runtimeSources = listOfKtFilesFrom(
     "libraries/stdlib/js/src/kotlin/reflect",
     "libraries/stdlib/js/src/kotlin/annotationsJVM.kt",
 
+    "libraries/stdlib/js/runtime/primitiveCompanionObjects.kt",
+
     "libraries/stdlib/src/kotlin/internal",
     "libraries/stdlib/src/kotlin/util/Standard.kt",
     "core/builtins/native/kotlin/Annotation.kt",