[Commonizer] Apply interner to avoid duplicated FqName objects

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/mergedtree/ir/CirAnnotation.kt

@@ -6,12 +6,13 @@
 package org.jetbrains.kotlin.descriptors.commonizer.mergedtree.ir
 
 import org.jetbrains.kotlin.descriptors.annotations.AnnotationDescriptor
+import org.jetbrains.kotlin.descriptors.commonizer.utils.intern
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.constants.*
 
 class CirAnnotation(original: AnnotationDescriptor) {
-    val fqName: FqName = original.fqName ?: error("Annotation with no FQ name: ${original::class.java}, $original")
+    val fqName: FqName = original.fqName?.intern() ?: error("Annotation with no FQ name: ${original::class.java}, $original")
     val allValueArguments: Map<Name, ConstantValue<*>> = original.allValueArguments
 
     init {

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/mergedtree/ir/CirClass.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.descriptors.commonizer.mergedtree.ir
 
 import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.commonizer.utils.intern
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
@@ -65,7 +66,7 @@ class CirClassImpl(original: ClassDescriptor) : CirClass {
     override val annotations = original.annotations.map(::CirAnnotation)
     override val name = original.name
     override val typeParameters = original.declaredTypeParameters.map(::CirTypeParameterImpl)
-    override val companion = original.companionObjectDescriptor?.fqNameSafe
+    override val companion = original.companionObjectDescriptor?.fqNameSafe?.intern()
     override val kind = original.kind
     override val modality = original.modality
     override val visibility = original.visibility

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/mergedtree/ir/CirType.kt

@@ -14,6 +14,7 @@ import org.jetbrains.kotlin.descriptors.commonizer.mergedtree.ir.CirSimpleTypeKi
 import org.jetbrains.kotlin.descriptors.commonizer.utils.declarationDescriptor
 import org.jetbrains.kotlin.descriptors.commonizer.utils.fqName
 import org.jetbrains.kotlin.descriptors.commonizer.utils.fqNameWithTypeParameters
+import org.jetbrains.kotlin.descriptors.commonizer.utils.intern
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.types.*
 
@@ -52,7 +53,7 @@ class CirSimpleType(original: SimpleType) : CirType() {
 
         annotations = abbreviation.annotations.map(::CirAnnotation)
         kind = CirSimpleTypeKind.determineKind(abbreviation.declarationDescriptor)
-        fqName = abbreviation.fqName
+        fqName = abbreviation.fqNameInterned
         arguments = abbreviation.arguments.map(::CirTypeProjection)
         isMarkedNullable = abbreviation.isMarkedNullable
         isDefinitelyNotNullType = abbreviation.isDefinitelyNotNullType
@@ -85,7 +86,7 @@ enum class CirSimpleTypeKind {
 }
 
 data class CirTypeConstructorId(val fqName: FqName, val numberOfTypeParameters: Int) {
-    constructor(type: SimpleType) : this(type.fqName, type.constructor.parameters.size)
+    constructor(type: SimpleType) : this(type.fqNameInterned, type.constructor.parameters.size)
 }
 
 class CirTypeProjection(original: TypeProjection) {

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/mergedtree/ir/nodeBuilders.kt

@@ -11,6 +11,7 @@ import org.jetbrains.kotlin.descriptors.commonizer.core.*
 import org.jetbrains.kotlin.descriptors.commonizer.mergedtree.ir.CirRootNode.ClassifiersCacheImpl
 import org.jetbrains.kotlin.descriptors.commonizer.utils.CommonizedGroup
 import org.jetbrains.kotlin.descriptors.commonizer.utils.firstNonNull
+import org.jetbrains.kotlin.descriptors.commonizer.utils.intern
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
@@ -100,7 +101,7 @@ internal fun buildClassNode(
     recursionMarker = CirClassRecursionMarker,
     nodeProducer = ::CirClassNode
 ).also { node ->
-    classes.firstNonNull().fqNameSafe.let { fqName ->
+    classes.firstNonNull().fqNameSafe.intern().let { fqName ->
         node.fqName = fqName
         cacheRW.classes.putSafe(fqName, node)
     }
@@ -132,7 +133,7 @@ internal fun buildTypeAliasNode(
     recursionMarker = CirClassRecursionMarker,
     nodeProducer = ::CirTypeAliasNode
 ).also { node ->
-    typeAliases.firstNonNull().fqNameSafe.let { fqName ->
+    typeAliases.firstNonNull().fqNameSafe.intern().let { fqName ->
         node.fqName = fqName
         cacheRW.typeAliases.putSafe(fqName, node)
     }

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/mergedtree/modules.kt

@@ -28,7 +28,7 @@ internal fun mergeModules(
 
     modules.forEachIndexed { index, module ->
         module?.collectNonEmptyPackageMemberScopes { packageFqName, memberScope ->
-            packageMemberScopesMap[packageFqName][index] = memberScope
+            packageMemberScopesMap[packageFqName.intern()][index] = memberScope
         }
     }
 

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/utils/NonThreadSafeInterner.kt

@@ -7,7 +7,7 @@ package org.jetbrains.kotlin.descriptors.commonizer.utils
 
 import java.util.WeakHashMap
 
-internal class Interner<T : Any> {
+internal class NonThreadSafeInterner<T : Any> {
     private val pool = WeakHashMap<T, T>()
 
     fun intern(value: T): T = pool.computeIfAbsent(value) { value }

native/commonizer/src/org/jetbrains/kotlin/descriptors/commonizer/utils/type.kt

@@ -17,8 +17,10 @@ import kotlin.collections.HashSet
 internal inline val KotlinType.declarationDescriptor: ClassifierDescriptor
     get() = (constructor.declarationDescriptor ?: error("No declaration descriptor found for $constructor"))
 
-internal inline val KotlinType.fqName: FqName
+internal inline val KotlinType.fqNameInterned: FqName
-    get() = declarationDescriptor.fqNameSafe
+    get() = declarationDescriptor.fqNameSafe.intern()
+
+internal fun FqName.intern(): FqName = fqNameInterner.intern(this)
 
 internal val KotlinType.fqNameWithTypeParameters: String
     get() {
@@ -27,7 +29,7 @@ internal val KotlinType.fqNameWithTypeParameters: String
     }
 
 private fun StringBuilder.buildFqNameWithTypeParameters(type: KotlinType, exploredTypeParameters: MutableSet<KotlinType>) {
-    append(type.fqName)
+    append(type.fqNameInterned)
 
     val typeParameterDescriptor = TypeUtils.getTypeParameterDescriptorOrNull(type)
     if (typeParameterDescriptor != null) {
@@ -70,4 +72,6 @@ private fun StringBuilder.buildFqNameWithTypeParameters(type: KotlinType, explor
 }
 
 // dedicated to hold unique entries of "fqNameWithTypeParameters"
-private val stringInterner = Interner<String>()
+private val stringInterner = NonThreadSafeInterner<String>()
+
+private val fqNameInterner = NonThreadSafeInterner<FqName>()

native/commonizer/tests/org/jetbrains/kotlin/descriptors/commonizer/utils/ComparingDeclarationsVisitor.kt

@@ -426,8 +426,8 @@ internal class ComparingDeclarationsVisitor(
             context.nextLevel("Unwrapped/unabbreviated type annotations")
         )
 
-        val expectedFqName = expectedUnwrapped.fqName
+        val expectedFqName = expectedUnwrapped.fqNameInterned
-        val actualFqName = actualUnwrapped.fqName
+        val actualFqName = actualUnwrapped.fqNameInterned
 
         context.assertEquals(expectedFqName, actualFqName, "type FQN")