K2: link via signatures if -Xlink-via-signatures is set

Related to KT-53505

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/FirKotlinToJvmBytecodeCompiler.kt

@@ -46,7 +46,6 @@ import org.jetbrains.kotlin.fir.pipeline.convertToIr
 import org.jetbrains.kotlin.fir.pipeline.runCheckers
 import org.jetbrains.kotlin.fir.pipeline.runResolution
 import org.jetbrains.kotlin.fir.resolve.ScopeSession
-import org.jetbrains.kotlin.fir.session.FirSessionFactory
 import org.jetbrains.kotlin.fir.session.FirSessionFactory.createSessionWithDependencies
 import org.jetbrains.kotlin.fir.session.IncrementalCompilationContext
 import org.jetbrains.kotlin.fir.session.environment.AbstractProjectEnvironment
@@ -186,7 +185,10 @@ object FirKotlinToJvmBytecodeCompiler {
         performanceManager?.notifyIRTranslationStarted()
 
         val fir2IrExtensions = JvmFir2IrExtensions(moduleConfiguration, JvmIrDeserializerImpl(), JvmIrMangler)
-        val fir2IrResult = firResult.session.convertToIr(firResult.scopeSession, firResult.fir, fir2IrExtensions, irGenerationExtensions)
+        val linkViaSignatures = moduleConfiguration.getBoolean(JVMConfigurationKeys.LINK_VIA_SIGNATURES)
+        val fir2IrResult = firResult.session.convertToIr(
+            firResult.scopeSession, firResult.fir, fir2IrExtensions, irGenerationExtensions, linkViaSignatures
+        )
 
         performanceManager?.notifyIRTranslationFinished()
 

compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/pipeline/compilerPipeline.kt

@@ -192,10 +192,13 @@ fun convertAnalyzedFirToIr(
 
     // fir2ir
     val irGenerationExtensions =
-        (environment.projectEnvironment as? VfsBasedProjectEnvironment)?.project?.let { IrGenerationExtension.getInstances(it) }
+        (environment.projectEnvironment as? VfsBasedProjectEnvironment)?.project?.let {
+            IrGenerationExtension.getInstances(it)
+        } ?: emptyList()
+    val linkViaSignatures = input.configuration.getBoolean(JVMConfigurationKeys.LINK_VIA_SIGNATURES)
     val (irModuleFragment, components) =
         analysisResults.session.convertToIr(
-            analysisResults.scopeSession, analysisResults.fir, extensions, irGenerationExtensions ?: emptyList()
+            analysisResults.scopeSession, analysisResults.fir, extensions, irGenerationExtensions, linkViaSignatures
         )
 
     return ModuleCompilerIrBackendInput(

compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/pipeline/convertToIr.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.fir.pipeline
 
 import org.jetbrains.kotlin.backend.common.extensions.IrGenerationExtension
+import org.jetbrains.kotlin.backend.jvm.serialization.JvmIdSignatureDescriptor
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.backend.Fir2IrConverter
 import org.jetbrains.kotlin.fir.backend.Fir2IrExtensions
@@ -19,6 +20,7 @@ import org.jetbrains.kotlin.fir.moduleData
 import org.jetbrains.kotlin.fir.resolve.ScopeSession
 import org.jetbrains.kotlin.fir.resolve.providers.firProvider
 import org.jetbrains.kotlin.fir.resolve.providers.impl.FirProviderImpl
+import org.jetbrains.kotlin.ir.backend.jvm.serialization.JvmDescriptorMangler
 import org.jetbrains.kotlin.ir.backend.jvm.serialization.JvmIrMangler
 import org.jetbrains.kotlin.ir.declarations.impl.IrFactoryImpl
 
@@ -26,19 +28,32 @@ fun FirSession.convertToIr(
     scopeSession: ScopeSession,
     firFiles: List<FirFile>,
     fir2IrExtensions: Fir2IrExtensions,
-    irGeneratorExtensions: Collection<IrGenerationExtension>
+    irGeneratorExtensions: Collection<IrGenerationExtension>,
+    linkViaSignatures: Boolean
 ): Fir2IrResult {
     val commonFirFiles = moduleData.dependsOnDependencies
         .map { it.session }
         .filter { it.kind == FirSession.Kind.Source }
         .flatMap { (it.firProvider as FirProviderImpl).getAllFirFiles() }
 
-    return Fir2IrConverter.createModuleFragmentWithoutSignatures(
-        this, scopeSession, firFiles + commonFirFiles,
-        languageVersionSettings, fir2IrExtensions,
-        FirJvmKotlinMangler(this),
-        JvmIrMangler, IrFactoryImpl, FirJvmVisibilityConverter,
-        Fir2IrJvmSpecialAnnotationSymbolProvider(),
-        irGeneratorExtensions
-    )
+    if (linkViaSignatures) {
+        val signaturer = JvmIdSignatureDescriptor(mangler = JvmDescriptorMangler(mainDetector = null))
+        return Fir2IrConverter.createModuleFragmentWithSignaturesIfNeeded(
+            this, scopeSession, firFiles + commonFirFiles,
+            languageVersionSettings, signaturer, fir2IrExtensions,
+            FirJvmKotlinMangler(this),
+            JvmIrMangler, IrFactoryImpl, FirJvmVisibilityConverter,
+            Fir2IrJvmSpecialAnnotationSymbolProvider(),
+            irGeneratorExtensions, true
+        )
+    } else {
+        return Fir2IrConverter.createModuleFragmentWithoutSignatures(
+            this, scopeSession, firFiles + commonFirFiles,
+            languageVersionSettings, fir2IrExtensions,
+            FirJvmKotlinMangler(this),
+            JvmIrMangler, IrFactoryImpl, FirJvmVisibilityConverter,
+            Fir2IrJvmSpecialAnnotationSymbolProvider(),
+            irGeneratorExtensions
+        )
+    }
 }

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java

@@ -18073,6 +18073,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/fir/KotlinDocumentationProvider.kt");
         }
 
+        @Test
+        @TestMetadata("linkViaSignatures.kt")
+        public void testLinkViaSignatures() throws Exception {
+            runTest("compiler/testData/codegen/box/fir/linkViaSignatures.kt");
+        }
+
         @Test
         @TestMetadata("LookupTags.kt")
         public void testLookupTags() throws Exception {

compiler/test-infrastructure/tests/org/jetbrains/kotlin/test/directives/LanguageSettingsDirectives.kt

@@ -76,6 +76,7 @@ object LanguageSettingsDirectives : SimpleDirectivesContainer() {
     val USE_TYPE_TABLE by directive("Use type table in metadata serialization")
     val NO_NEW_JAVA_ANNOTATION_TARGETS by directive("Do not generate Java annotation targets TYPE_USE/TYPE_PARAMETER for Kotlin annotation classes with Kotlin targets TYPE/TYPE_PARAMETER")
     val OLD_INNER_CLASSES_LOGIC by directive("Use old logic for generation of InnerClasses attributes")
+    val LINK_VIA_SIGNATURES by directive("Use linkage via signatures instead of descriptors / FIR")
 
     // --------------------- Utils ---------------------
 

compiler/testData/codegen/box/fir/linkViaSignatures.kt

@@ -0,0 +1,26 @@
+// WITH_STDLIB
+// TARGET_BACKEND: JVM_IR
+// LINK_VIA_SIGNATURES
+
+class Class
+interface Interface
+sealed class Sealed<T>
+enum class E { ENTRY }
+
+fun function(s: String): Array<Int> {
+    fun Boolean.local() {}
+    return arrayOf(s.length)
+}
+typealias S = String
+var property: S? = "OK"
+
+fun box(): String {
+    val c = Class()
+    val o = object : Interface {}
+    if (property != "OK") return property!!
+    if (E.ENTRY.ordinal != 0) return E.ENTRY.ordinal.toString()
+    val result = function("AlphaBeta")
+    if (result.size != 1) return result.size.toString()
+    if (result[0] != 9) return result[0].toString()
+    return "OK"
+}

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java

@@ -18073,6 +18073,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/fir/KotlinDocumentationProvider.kt");
         }
 
+        @Test
+        @TestMetadata("linkViaSignatures.kt")
+        public void testLinkViaSignatures() throws Exception {
+            runTest("compiler/testData/codegen/box/fir/linkViaSignatures.kt");
+        }
+
         @Test
         @TestMetadata("LookupTags.kt")
         public void testLookupTags() throws Exception {

compiler/tests-common-new/tests/org/jetbrains/kotlin/test/services/configuration/JvmEnvironmentConfigurator.kt

@@ -48,6 +48,7 @@ import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.NO_OPTIMI
 import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.NO_UNIFIED_NULL_CHECKS
 import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.PARAMETERS_METADATA
 import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.JDK_RELEASE
+import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.LINK_VIA_SIGNATURES
 import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.NO_NEW_JAVA_ANNOTATION_TARGETS
 import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.OLD_INNER_CLASSES_LOGIC
 import org.jetbrains.kotlin.test.directives.LanguageSettingsDirectives.USE_TYPE_TABLE
@@ -177,6 +178,7 @@ class JvmEnvironmentConfigurator(testServices: TestServices) : EnvironmentConfig
         register(ENABLE_DEBUG_MODE, JVMConfigurationKeys.ENABLE_DEBUG_MODE)
         register(NO_NEW_JAVA_ANNOTATION_TARGETS, JVMConfigurationKeys.NO_NEW_JAVA_ANNOTATION_TARGETS)
         register(OLD_INNER_CLASSES_LOGIC, JVMConfigurationKeys.OLD_INNER_CLASSES_LOGIC)
+        register(LINK_VIA_SIGNATURES, JVMConfigurationKeys.LINK_VIA_SIGNATURES)
     }
 
     override fun configureCompilerConfiguration(configuration: CompilerConfiguration, module: TestModule) {