[FIR2IR] Add primitive signature composer & use it for external classes

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrClassifierStorage.kt

@@ -354,6 +354,14 @@ class Fir2IrClassifierStorage(
         if (firClass is FirAnonymousObject || firClass is FirRegularClass && firClass.visibility == Visibilities.LOCAL) {
             return createIrClass(firClass).symbol
         }
+        val signature = signatureComposer.composeSignature(firClass)
+        symbolTable.referenceClassIfAny(signature)?.let { irClassSymbol ->
+            val irClass = irClassSymbol.owner
+            classCache[firClass as FirRegularClass] = irClass
+            processClassHeader(firClass, irClass)
+            declarationStorage.preCacheBuiltinClassMembers(firClass, irClass)
+            return irClassSymbol
+        }
         // TODO: remove all this code and change to unbound symbol creation
         val classId = firClassSymbol.classId
         val parentId = classId.outerClassId

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrComponents.kt

@@ -18,4 +18,5 @@ interface Fir2IrComponents {
     val classifierStorage: Fir2IrClassifierStorage
     val declarationStorage: Fir2IrDeclarationStorage
     val typeConverter: Fir2IrTypeConverter
+    val signatureComposer: Fir2IrSignatureComposer
 }

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrComponentsStorage.kt

@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.fir.backend
 
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.resolve.ScopeSession
+import org.jetbrains.kotlin.fir.signaturer.FirBasedSignatureComposer
 import org.jetbrains.kotlin.ir.descriptors.IrBuiltIns
 import org.jetbrains.kotlin.ir.util.SymbolTable
 
@@ -19,4 +20,6 @@ class Fir2IrComponentsStorage(
     override lateinit var classifierStorage: Fir2IrClassifierStorage
     override lateinit var declarationStorage: Fir2IrDeclarationStorage
     override lateinit var typeConverter: Fir2IrTypeConverter
+
+    override val signatureComposer = FirBasedSignatureComposer()
 }

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrSignatureComposer.kt

@@ -0,0 +1,13 @@
+/*
+ * Copyright 2010-2020 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.fir.backend
+
+import org.jetbrains.kotlin.fir.declarations.FirDeclaration
+import org.jetbrains.kotlin.ir.util.IdSignature
+
+interface Fir2IrSignatureComposer {
+    fun composeSignature(declaration: FirDeclaration): IdSignature
+}

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/signaturer/FirBasedSignatureComposer.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2010-2020 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.fir.signaturer
+
+import org.jetbrains.kotlin.descriptors.Visibilities
+import org.jetbrains.kotlin.fir.FirElement
+import org.jetbrains.kotlin.fir.backend.Fir2IrSignatureComposer
+import org.jetbrains.kotlin.fir.declarations.*
+import org.jetbrains.kotlin.fir.render
+import org.jetbrains.kotlin.fir.visitors.FirVisitorVoid
+import org.jetbrains.kotlin.ir.util.IdSignature
+
+class FirBasedSignatureComposer : Fir2IrSignatureComposer {
+
+    class SignatureBuilder : FirVisitorVoid() {
+        var hashId: Long? = null
+        var mask = 0L
+
+        private fun setExpected(f: Boolean) {
+            mask = mask or IdSignature.Flags.IS_EXPECT.encode(f)
+        }
+
+        override fun visitElement(element: FirElement) {
+            TODO("Not yet implemented")
+        }
+
+        override fun visitRegularClass(regularClass: FirRegularClass) {
+            setExpected(regularClass.isExpect)
+            //platformSpecificClass(descriptor)
+        }
+    }
+
+    override fun composeSignature(declaration: FirDeclaration): IdSignature {
+        val builder = SignatureBuilder()
+        declaration.accept(builder)
+        if (declaration is FirRegularClass && declaration.visibility != Visibilities.LOCAL) {
+            val classId = declaration.classId
+            return IdSignature.PublicSignature(classId.packageFqName, classId.relativeClassName, builder.hashId, builder.mask)
+        }
+        throw AssertionError("Unsupported FIR declaration in signature composer: ${declaration.render()}")
+    }
+}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/SymbolTable.kt

@@ -421,6 +421,9 @@ open class SymbolTable(
     override fun referenceClass(descriptor: ClassDescriptor) =
         classSymbolTable.referenced(descriptor) { createClassSymbol(descriptor) }
 
+    fun referenceClassIfAny(sig: IdSignature): IrClassSymbol? =
+        classSymbolTable.get(sig)
+
     override fun referenceClassFromLinker(descriptor: ClassDescriptor, sig: IdSignature): IrClassSymbol =
         classSymbolTable.run {
             if (sig.isPublic) referenced(sig) { IrClassPublicSymbolImpl(descriptor, sig) }

compiler/testData/codegen/box/builtinStubMethods/Collection.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // TARGET_BACKEND: JVM
 
 class MyCollection<T>: Collection<T> {

compiler/testData/codegen/box/builtinStubMethods/immutableRemove.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // SKIP_JDK6
 // TARGET_BACKEND: JVM
 // FULL_JDK

compiler/testData/codegen/box/builtinStubMethods/nonTrivialSubstitution.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // TARGET_BACKEND: JVM
 
 class MyCollection<T> : Collection<List<Iterator<T>>> {

compiler/testData/codegen/box/collections/removeClash.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 class Queue<T>(override val size: Int) : Collection<T> {
     override fun contains(element: T): Boolean = TODO()
 

compiler/testData/codegen/box/collections/toArrayInJavaClass.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // TARGET_BACKEND: JVM
 
 // WITH_RUNTIME

compiler/testData/codegen/box/inlineClasses/callSpeciallyOverriddenPropertyOfInlineClass.kt

@@ -1,5 +1,4 @@
 // !LANGUAGE: +InlineClasses
-// IGNORE_BACKEND_FIR: JVM_IR
 // TARGET_BACKEND: JVM
 
 inline class UInt(val x: Int)

compiler/testData/codegen/box/specialBuiltins/redundantStubForSize.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 open class A1 {
     open val size: Int = 56
 }

compiler/testData/codegen/box/toArray/incorrectToArrayDetection.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // SKIP_JDK6
 // TARGET_BACKEND: JVM
 // FULL_JDK

compiler/testData/codegen/box/toArray/toArrayAlreadyPresent.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // TARGET_BACKEND: JVM
 
 // WITH_RUNTIME

compiler/testData/ir/irText/classes/dataClassesGeneric.fir.txt

@@ -175,7 +175,7 @@ FILE fqName:<root> fileName:/dataClassesGeneric.kt
       $this: VALUE_PARAMETER GENERATED_DATA_CLASS_MEMBER name:<this> type:<root>.Test2<T of <root>.Test2>
       BLOCK_BODY
         RETURN type=kotlin.Nothing from='public open fun hashCode (): kotlin.Int declared in <root>.Test2'
-          CALL 'public open fun hashCode (): kotlin.Int declared in kotlin.Any' type=kotlin.Int origin=null
+          CALL 'public open fun hashCode (): kotlin.Int [fake_override] declared in kotlin.Number' type=kotlin.Int origin=null
             $this: GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:x type:T of <root>.Test2 visibility:private [final]' type=T of <root>.Test2 origin=null
               receiver: GET_VAR '<this>: <root>.Test2<T of <root>.Test2> declared in <root>.Test2.hashCode' type=<root>.Test2<T of <root>.Test2> origin=null
     FUN GENERATED_DATA_CLASS_MEMBER name:toString visibility:public modality:OPEN <> ($this:<root>.Test2<T of <root>.Test2>) returnType:kotlin.String