JVM_IR: KT-40330 Unify field names for captured 'this' with JVM

NB some cases such as captured extension receiver for an extension lambda are not supported yet; to be discussed, to what extent should we actually follow JVM code shape here.
2020-08-18 15:26:36 +03:00
parent 24bfc155af
commit 8f0aecce58
16 changed files with 371 additions and 22 deletions
@@ -6,7 +6,7 @@
 package org.jetbrains.kotlin.backend.common.lower

 import org.jetbrains.kotlin.backend.common.*
-import org.jetbrains.kotlin.backend.common.descriptors.synthesizedName
+import org.jetbrains.kotlin.backend.common.descriptors.synthesizedString
 import org.jetbrains.kotlin.backend.common.ir.*
 import org.jetbrains.kotlin.descriptors.Modality
 import org.jetbrains.kotlin.descriptors.ReceiverParameterDescriptor
@@ -31,11 +31,13 @@ import org.jetbrains.kotlin.ir.types.impl.makeTypeProjection
 import org.jetbrains.kotlin.ir.util.constructedClass
 import org.jetbrains.kotlin.ir.util.file
 import org.jetbrains.kotlin.ir.util.parentAsClass
+import org.jetbrains.kotlin.ir.util.render
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
 import org.jetbrains.kotlin.ir.visitors.acceptVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.utils.addToStdlib.safeAs

 interface LocalNameProvider {
    fun localName(declaration: IrDeclarationWithName): String =
@@ -637,7 +639,7 @@ class LocalDeclarationsLowering(
            oldDeclaration: IrFunction,
            newDeclaration: IrFunction
        ) = ArrayList<IrValueParameter>(capturedValues.size + oldDeclaration.valueParameters.size).apply {
-            val generatedNames = mutableSetOf<Name>()
+            val generatedNames = mutableSetOf<String>()
            capturedValues.mapIndexedTo(this) { i, capturedValue ->
                val p = capturedValue.owner
                buildValueParameter(newDeclaration) {
@@ -743,7 +745,7 @@ class LocalDeclarationsLowering(

        private fun createFieldsForCapturedValues(localClassContext: LocalClassContext) {
            val classDeclaration = localClassContext.declaration
-            val generatedNames = mutableSetOf<Name>()
+            val generatedNames = mutableSetOf<String>()
            localClassContext.closure.capturedValues.forEach { capturedValue ->

                val owner = capturedValue.owner
@@ -772,18 +774,64 @@ class LocalDeclarationsLowering(
        private fun Name.stripSpecialMarkers(): String =
            if (isSpecial) asString().substring(1, asString().length - 1) else asString()

-        private fun suggestNameForCapturedValue(declaration: IrValueDeclaration, existing: MutableSet<Name>): Name {
+        private fun suggestNameForCapturedValue(declaration: IrValueDeclaration, usedNames: MutableSet<String>): Name {
+            if (declaration is IrValueParameter && declaration.name.asString() == "<this>") {
+                if (declaration.isDispatchReceiver()) {
+                    return findFirstUnusedName("this\$0", usedNames) {
+                        "this\$$it"
+                    }
+                } else if (declaration.isExtensionReceiver()) {
+                    val parentNameSuffix = declaration.parentNameSuffixForExtensionReceiver
+                    return findFirstUnusedName("\$this_$parentNameSuffix", usedNames) {
+                        "\$this_$parentNameSuffix\$$it"
+                    }
+                }
+                // TODO captured extension receivers of extension lambdas?
+            }
            val base = if (declaration.name.isSpecial)
                declaration.name.stripSpecialMarkers()
            else
                declaration.name.asString()
-            var chosen = base.synthesizedName
-            var suffix = 0
-            while (!existing.add(chosen))
-                chosen = "$base$${++suffix}".synthesizedName
-            return chosen
+            return findFirstUnusedName(base.synthesizedString, usedNames) {
+                "$base$$it".synthesizedString
+            }
        }

+        private inline fun findFirstUnusedName(initialName: String, usedNames: MutableSet<String>, nextName: (Int) -> String): Name {
+            var chosen = initialName
+            var suffix = 0
+            while (!usedNames.add(chosen))
+                chosen = nextName(++suffix)
+            return Name.identifier(chosen)
+        }
+
+        private fun IrValueParameter.isDispatchReceiver(): Boolean =
+            when (val parent = this.parent) {
+                is IrFunction ->
+                    parent.dispatchReceiverParameter == this
+                is IrClass ->
+                    parent.thisReceiver == this
+                else ->
+                    false
+            }
+
+        private fun IrValueParameter.isExtensionReceiver(): Boolean {
+            val parentFun = parent as? IrFunction ?: return false
+            return parentFun.extensionReceiverParameter == this
+        }
+
+        private val IrValueParameter.parentNameSuffixForExtensionReceiver: String
+            get() {
+                val parentFun = parent as? IrSimpleFunction
+                    ?: throw AssertionError("Extension receiver parent is not a simple function: ${parent.render()}")
+                val correspondingProperty = parentFun.safeAs<IrSimpleFunction>()?.correspondingPropertySymbol?.owner
+                return when {
+                    correspondingProperty != null ->
+                        correspondingProperty.name.stripSpecialMarkers()
+                    else ->
+                        parentFun.name.stripSpecialMarkers()
+                }
+            }

        private fun collectClosureForLocalDeclarations() {
            //TODO: maybe use for granular declarations