[IR, Native] Refactoring: Introduce KonanUnlinkedDeclarationsSupport

^KT-50775

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/PsiToIr.kt

@@ -106,6 +106,8 @@ internal fun Context.psiToIr(
                         config.resolve.includedLibraries.map { it.uniqueName }
                 ).associateWith { friendModules }
 
+        val unlinkedDeclarationsSupport = KonanUnlinkedDeclarationsSupport(generatorContext.irBuiltIns, allowUnboundSymbols)
+
         KonanIrLinker(
                 currentModule = moduleDescriptor,
                 translationPluginContext = translationContext,
@@ -119,8 +121,8 @@ internal fun Context.psiToIr(
                 exportedDependencies = exportedDependencies,
                 cachedLibraries = config.cachedLibraries,
                 lazyIrForCaches = config.lazyIrForCaches,
-                userVisibleIrModulesSupport = config.userVisibleIrModulesSupport,
-                allowUnboundSymbols = allowUnboundSymbols
+                unlinkedDeclarationsSupport = unlinkedDeclarationsSupport,
+                userVisibleIrModulesSupport = config.userVisibleIrModulesSupport
         ).also { linker ->
 
             // context.config.librariesWithDependencies could change at each iteration.

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/KonanIrlinker.kt

@@ -25,6 +25,7 @@ import org.jetbrains.kotlin.backend.common.serialization.encodings.BinaryNameAnd
 import org.jetbrains.kotlin.backend.common.serialization.encodings.BinarySymbolData
 import org.jetbrains.kotlin.backend.common.serialization.encodings.FunctionFlags
 import org.jetbrains.kotlin.backend.common.serialization.linkerissues.UserVisibleIrModulesSupport
+import org.jetbrains.kotlin.backend.common.serialization.unlinked.UnlinkedDeclarationsSupport
 import org.jetbrains.kotlin.backend.konan.*
 import org.jetbrains.kotlin.backend.konan.descriptors.ClassLayoutBuilder
 import org.jetbrains.kotlin.backend.konan.descriptors.findPackage
@@ -321,8 +322,8 @@ internal class KonanIrLinker(
         exportedDependencies: List<ModuleDescriptor>,
         private val cachedLibraries: CachedLibraries,
         private val lazyIrForCaches: Boolean,
-        override val userVisibleIrModulesSupport: UserVisibleIrModulesSupport,
-        allowUnboundSymbols: Boolean // TODO
+        override val unlinkedDeclarationsSupport: UnlinkedDeclarationsSupport,
+        override val userVisibleIrModulesSupport: UserVisibleIrModulesSupport
 ) : KotlinIrLinker(currentModule, messageLogger, builtIns, symbolTable, exportedDependencies) {
 
     companion object {

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/KonanUnlinkedDeclarationsSupport.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2010-2022 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.konan.serialization
+
+import org.jetbrains.kotlin.backend.common.serialization.unlinked.UnlinkedDeclarationsSupport
+import org.jetbrains.kotlin.backend.common.serialization.unlinked.UnlinkedDeclarationsSupport.UnlinkedMarkerTypeHandler
+import org.jetbrains.kotlin.ir.IrBuiltIns
+import org.jetbrains.kotlin.ir.types.IrErrorType
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.types.impl.IrSimpleTypeImpl
+
+/**
+ * Kotlin/Native backend does not support [IrErrorType].
+ * So, let's use a special instance of nullable [kotlin.Any] as a marker-type instead.
+ */
+class KonanUnlinkedDeclarationsSupport(irBuiltIns: IrBuiltIns, override val allowUnboundSymbols: Boolean) : UnlinkedDeclarationsSupport {
+    private val handler = object : UnlinkedMarkerTypeHandler {
+        override val unlinkedMarkerType = IrSimpleTypeImpl(
+                classifier = irBuiltIns.anyClass,
+                hasQuestionMark = true,
+                arguments = emptyList(),
+                annotations = emptyList()
+        )
+
+        override fun IrType.isUnlinkedMarkerType(): Boolean = this === unlinkedMarkerType
+    }
+
+    override fun <T : Any> whenUnboundSymbolsAllowed(action: (UnlinkedMarkerTypeHandler) -> T): T? =
+            if (allowUnboundSymbols) action(handler) else null
+}