[JS IR BE] Support bridges for special methods

Mostly reused from JVM IR lowering.
Shared logic moved to common backend module.

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/SpecialBridgeMethods.kt

@@ -0,0 +1,88 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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.backend.common.lower
+
+import org.jetbrains.kotlin.backend.common.CommonBackendContext
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
+import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
+import org.jetbrains.kotlin.ir.expressions.IrConstKind
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
+import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
+import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
+import org.jetbrains.kotlin.ir.util.parentAsClass
+import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
+
+class SpecialBridgeMethods(val context: CommonBackendContext) {
+    private data class SpecialMethodDescription(val kotlinFqClassName: FqName?, val name: Name, val arity: Int)
+
+    private fun makeDescription(classFqName: String, funName: String, arity: Int) =
+        SpecialMethodDescription(
+            FqName(classFqName),
+            Name.identifier(funName),
+            arity
+        )
+
+    private fun IrSimpleFunction.toDescription() = SpecialMethodDescription(
+        parentAsClass.fqNameWhenAvailable,
+        name,
+        valueParameters.size
+    )
+
+    @Suppress("UNUSED_PARAMETER")
+    private fun constFalse(bridge: IrSimpleFunction) =
+        IrConstImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, context.irBuiltIns.booleanType, IrConstKind.Boolean, false)
+
+    @Suppress("UNUSED_PARAMETER")
+    private fun constNull(bridge: IrSimpleFunction) =
+        IrConstImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, context.irBuiltIns.anyNType, IrConstKind.Null, null)
+
+    @Suppress("UNUSED_PARAMETER")
+    private fun constMinusOne(bridge: IrSimpleFunction) =
+        IrConstImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, context.irBuiltIns.intType, IrConstKind.Int, -1)
+
+    private fun getSecondArg(bridge: IrSimpleFunction) =
+        IrGetValueImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, bridge.valueParameters[1].symbol)
+
+    private val SPECIAL_METHODS_WITH_DEFAULTS_MAP = mapOf<SpecialMethodDescription, (IrSimpleFunction) -> IrExpression>(
+        makeDescription("kotlin.collections.Collection", "contains", 1) to ::constFalse,
+        makeDescription("kotlin.collections.MutableCollection", "remove", 1) to ::constFalse,
+        makeDescription("kotlin.collections.Map", "containsKey", 1) to ::constFalse,
+        makeDescription("kotlin.collections.Map", "containsValue", 1) to ::constFalse,
+        makeDescription("kotlin.collections.MutableMap", "remove", 2) to ::constFalse,
+        makeDescription("kotlin.collections.Map", "getOrDefault", 1) to ::getSecondArg,
+        makeDescription("kotlin.collections.Map", "get", 1) to ::constNull,
+        makeDescription("kotlin.collections.MutableMap", "remove", 1) to ::constNull,
+        makeDescription("kotlin.collections.List", "indexOf", 1) to ::constMinusOne,
+        makeDescription("kotlin.collections.List", "lastIndexOf", 1) to ::constMinusOne
+    )
+
+    fun findSpecialWithOverride(irFunction: IrSimpleFunction): Pair<IrSimpleFunction, (IrSimpleFunction) -> IrExpression>? {
+        irFunction.allOverridden().forEach { overridden ->
+            val description = overridden.toDescription()
+            SPECIAL_METHODS_WITH_DEFAULTS_MAP[description]?.let {
+                return Pair(overridden, it)
+            }
+        }
+        return null
+    }
+}
+
+fun IrSimpleFunction.allOverridden(): Sequence<IrSimpleFunction> {
+    val visited = mutableSetOf<IrSimpleFunction>()
+
+    fun IrSimpleFunction.search(): Sequence<IrSimpleFunction> {
+        if (this in visited) return emptySequence()
+        return sequence {
+            yield(this@search)
+            visited.add(this@search)
+            overriddenSymbols.forEach { yieldAll(it.owner.search()) }
+        }
+    }
+
+    return search().drop(1) // First element is `this`
+}

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

@@ -7,14 +7,15 @@ package org.jetbrains.kotlin.ir.backend.js.lower
 
 import org.jetbrains.kotlin.backend.common.ClassLoweringPass
 import org.jetbrains.kotlin.backend.common.bridges.FunctionHandle
-import org.jetbrains.kotlin.backend.common.bridges.findInterfaceImplementation
 import org.jetbrains.kotlin.backend.common.bridges.generateBridges
 import org.jetbrains.kotlin.backend.common.ir.copyTo
 import org.jetbrains.kotlin.backend.common.ir.copyTypeParametersFrom
 import org.jetbrains.kotlin.backend.common.ir.isMethodOfAny
 import org.jetbrains.kotlin.backend.common.ir.isSuspend
+import org.jetbrains.kotlin.backend.common.lower.SpecialBridgeMethods
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
 import org.jetbrains.kotlin.backend.common.lower.irBlockBody
+import org.jetbrains.kotlin.backend.common.lower.irNot
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.ir.backend.js.JsIrBackendContext
 import org.jetbrains.kotlin.ir.backend.js.JsLoweredDeclarationOrigin
@@ -29,7 +30,6 @@ import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.types.classifierOrNull
 import org.jetbrains.kotlin.ir.types.isUnit
 import org.jetbrains.kotlin.ir.util.*
-import org.jetbrains.kotlin.resolve.DescriptorUtils
 
 // Constructs bridges for inherited generic functions
 //
@@ -52,6 +52,8 @@ import org.jetbrains.kotlin.resolve.DescriptorUtils
 //
 class BridgesConstruction(val context: JsIrBackendContext) : ClassLoweringPass {
 
+    private val specialBridgeMethods = SpecialBridgeMethods(context)
+
     override fun lower(irClass: IrClass) {
         irClass.declarations
             .asSequence()
@@ -66,6 +68,11 @@ class BridgesConstruction(val context: JsIrBackendContext) : ClassLoweringPass {
         if (function.isMethodOfAny())
             return
 
+        val (specialOverride: IrSimpleFunction?, specialOverrideValueGenerator) =
+            specialBridgeMethods.findSpecialWithOverride(function) ?: Pair(null, null)
+
+        val specialOverrideSignature = specialOverride?.let { FunctionAndSignature(it) }
+
         val bridgesToGenerate = generateBridges(
             function = IrBasedFunctionHandle(function),
             signature = { FunctionAndSignature(it.function) }
@@ -85,7 +92,16 @@ class BridgesConstruction(val context: JsIrBackendContext) : ClassLoweringPass {
                 continue
             }
 
-            irClass.declarations.add(createBridge(function, from.function, to.function))
+            val bridge: IrDeclaration = when {
+                specialOverrideSignature == from ->
+                    createBridge(function, from.function, to.function, specialOverrideValueGenerator)
+
+                else ->
+                    createBridge(function, from.function, to.function, null)
+            }
+
+
+            irClass.declarations.add(bridge)
         }
     }
 
@@ -95,7 +111,8 @@ class BridgesConstruction(val context: JsIrBackendContext) : ClassLoweringPass {
     private fun createBridge(
         function: IrSimpleFunction,
         bridge: IrSimpleFunction,
-        delegateTo: IrSimpleFunction
+        delegateTo: IrSimpleFunction,
+        defaultValueGenerator: ((IrSimpleFunction) -> IrExpression)?
     ): IrFunction {
 
         val origin =
@@ -130,6 +147,16 @@ class BridgesConstruction(val context: JsIrBackendContext) : ClassLoweringPass {
         }
 
         context.createIrBuilder(irFunction.symbol).irBlockBody(irFunction) {
+            if (defaultValueGenerator != null) {
+                irFunction.valueParameters.forEach {
+                    +irIfThen(
+                        context.irBuiltIns.unitType,
+                        irNot(irIs(irGet(it), delegateTo.valueParameters[it.index].type)),
+                        irReturn(defaultValueGenerator(irFunction))
+                    )
+                }
+            }
+
             val call = irCall(delegateTo.symbol)
             call.dispatchReceiver = irGet(irFunction.dispatchReceiverParameter!!)
             irFunction.extensionReceiverParameter?.let {

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/irCodegenUtils.kt

@@ -7,8 +7,8 @@ package org.jetbrains.kotlin.backend.jvm.codegen
 
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.backend.common.ir.ir2string
+import org.jetbrains.kotlin.backend.common.lower.allOverridden
 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
-import org.jetbrains.kotlin.backend.jvm.lower.allOverridden
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.builtins.jvm.JavaToKotlinClassMap
 import org.jetbrains.kotlin.codegen.*

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

@@ -6,6 +6,8 @@
 package org.jetbrains.kotlin.backend.jvm.lower
 
 import org.jetbrains.kotlin.backend.common.ClassLoweringPass
+import org.jetbrains.kotlin.backend.common.lower.SpecialBridgeMethods
+import org.jetbrains.kotlin.backend.common.lower.allOverridden
 import org.jetbrains.kotlin.backend.common.bridges.FunctionHandle
 import org.jetbrains.kotlin.backend.common.bridges.findAllReachableDeclarations
 import org.jetbrains.kotlin.backend.common.bridges.findConcreteSuperDeclaration
@@ -25,12 +27,9 @@ import org.jetbrains.kotlin.ir.builders.*
 import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.declarations.impl.IrFunctionImpl
 import org.jetbrains.kotlin.ir.declarations.impl.IrValueParameterImpl
-import org.jetbrains.kotlin.ir.expressions.IrConstKind
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
 import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrGetValueImpl
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrTypeParameterSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrSimpleFunctionSymbolImpl
@@ -45,7 +44,6 @@ import org.jetbrains.kotlin.ir.util.defaultType
 import org.jetbrains.kotlin.ir.util.fqNameWhenAvailable
 import org.jetbrains.kotlin.ir.util.isInterface
 import org.jetbrains.kotlin.ir.util.parentAsClass
-import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 import org.jetbrains.org.objectweb.asm.commons.Method
@@ -62,6 +60,8 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass
 
     private val typeMapper = state.typeMapper
 
+    private val specialBridgeMethods = SpecialBridgeMethods(context)
+
     override fun lower(irClass: IrClass) {
         // TODO: Bridges should be generated for @JvmDefaults, so the interface check is too optimistic.
         if (irClass.isInterface || irClass.origin == JvmLoweredDeclarationOrigin.DEFAULT_IMPLS) {
@@ -91,7 +91,7 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass
         val ourMethodName = ourSignature.name
 
         val (specialOverride, specialOverrideValueGenerator) =
-            findSpecialWithOverride(irFunction) ?: Pair(null, null)
+            specialBridgeMethods.findSpecialWithOverride(irFunction) ?: Pair(null, null)
         val specialOverrideSignature = specialOverride?.getJvmSignature()
 
 
@@ -389,46 +389,7 @@ private class BridgeLowering(val context: JvmBackendContext) : ClassLoweringPass
         }
     }
 
-    private data class SpecialMethodDescription(val kotlinFqClassName: FqName?, val name: Name, val arity: Int)
 
-    private fun makeDescription(classFqName: String, funName: String, arity: Int) = SpecialMethodDescription(FqName(classFqName), Name.identifier(funName), arity)
-
-    private fun IrSimpleFunction.toDescription() = SpecialMethodDescription(parentAsClass.fqNameWhenAvailable, name, valueParameters.size)
-
-    private fun constFalse(bridge: IrSimpleFunction) =
-        IrConstImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, context.irBuiltIns.booleanType, IrConstKind.Boolean, false)
-
-    private fun constNull(bridge: IrSimpleFunction) =
-        IrConstImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, context.irBuiltIns.anyNType, IrConstKind.Null, null)
-
-    private fun constMinusOne(bridge: IrSimpleFunction) =
-        IrConstImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, context.irBuiltIns.intType, IrConstKind.Int, -1)
-
-    private fun getSecondArg(bridge: IrSimpleFunction) =
-        IrGetValueImpl(UNDEFINED_OFFSET, UNDEFINED_OFFSET, bridge.valueParameters[1].symbol)
-
-    private val SPECIAL_METHODS_WITH_DEFAULTS_MAP = mapOf<SpecialMethodDescription, (IrSimpleFunction) -> IrExpression>(
-        makeDescription("kotlin.collections.Collection", "contains", 1) to ::constFalse,
-        makeDescription("kotlin.collections.MutableCollection", "remove", 1) to ::constFalse,
-        makeDescription("kotlin.collections.Map", "containsKey", 1) to ::constFalse,
-        makeDescription("kotlin.collections.Map", "containsValue", 1) to ::constFalse,
-        makeDescription("kotlin.collections.MutableMap", "remove", 2) to ::constFalse,
-        makeDescription("kotlin.collections.Map", "getOrDefault", 1) to ::getSecondArg,
-        makeDescription("kotlin.collections.Map", "get", 1) to ::constNull,
-        makeDescription("kotlin.collections.MutableMap", "remove", 1) to ::constNull,
-        makeDescription("kotlin.collections.List", "indexOf", 1) to ::constMinusOne,
-        makeDescription("kotlin.collections.List", "lastIndexOf", 1) to ::constMinusOne
-    )
-
-    private fun findSpecialWithOverride(irFunction: IrSimpleFunction): Pair<IrSimpleFunction, (IrSimpleFunction) -> IrExpression>? {
-        irFunction.allOverridden().forEach { overridden ->
-            val description = overridden.toDescription()
-            SPECIAL_METHODS_WITH_DEFAULTS_MAP[description]?.let {
-                return Pair(overridden, it)
-            }
-        }
-        return null
-    }
 
     private inner class FunctionHandleForIrFunction(val irFunction: IrSimpleFunction) : FunctionHandle {
         override val isDeclaration get() = irFunction.origin != IrDeclarationOrigin.FAKE_OVERRIDE
@@ -464,20 +425,6 @@ private data class SignatureWithSource(val signature: Method, val source: IrSimp
     }
 }
 
-fun IrSimpleFunction.allOverridden(): Sequence<IrSimpleFunction> {
-    val visited = mutableSetOf<IrSimpleFunction>()
-
-    fun IrSimpleFunction.search(): Sequence<IrSimpleFunction> {
-        if (this in visited) return emptySequence()
-        return sequence {
-            yield(this@search)
-            visited.add(this@search)
-            overriddenSymbols.forEach { yieldAll(it.owner.search()) }
-        }
-    }
-
-    return search().drop(1) // First element is `this`
-}
 
 fun IrSimpleFunction.overriddenInClasses(): Sequence<IrSimpleFunction> =
     allOverridden().filter { !(it.parent.safeAs<IrClass>()?.isInterface ?: true) }