[FIR] Introduce isRealOwnerOf utility function

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

@@ -446,33 +446,33 @@ fun FirTypeScope.processOverriddenFunctionsFromSuperClasses(
     functionSymbol: FirNamedFunctionSymbol,
     containingClass: FirClass,
     processor: (FirNamedFunctionSymbol) -> ProcessorAction
-): ProcessorAction =
-    processDirectOverriddenFunctionsWithBaseScope(functionSymbol) { overridden, _ ->
-        val unwrapped = if (overridden.fir.isSubstitutionOverride &&
-            overridden.dispatchReceiverClassLookupTagOrNull() == containingClass.symbol.toLookupTag()
-        )
+): ProcessorAction {
+    val ownerTag = containingClass.symbol.toLookupTag()
+    return processDirectOverriddenFunctionsWithBaseScope(functionSymbol) { overridden, _ ->
+        val unwrapped = if (overridden.fir.isSubstitutionOverride && ownerTag.isRealOwnerOf(overridden))
             overridden.originalForSubstitutionOverride!!
         else
             overridden
 
         processor(unwrapped)
     }
+}
 
 fun FirTypeScope.processOverriddenPropertiesFromSuperClasses(
     propertySymbol: FirPropertySymbol,
     containingClass: FirClass,
     processor: (FirPropertySymbol) -> ProcessorAction
-): ProcessorAction =
-    processDirectOverriddenPropertiesWithBaseScope(propertySymbol) { overridden, _ ->
-        val unwrapped = if (overridden.fir.isSubstitutionOverride &&
-            overridden.dispatchReceiverClassLookupTagOrNull() == containingClass.symbol.toLookupTag()
-        )
+): ProcessorAction {
+    val ownerTag = containingClass.symbol.toLookupTag()
+    return processDirectOverriddenPropertiesWithBaseScope(propertySymbol) { overridden, _ ->
+        val unwrapped = if (overridden.fir.isSubstitutionOverride && ownerTag.isRealOwnerOf(overridden))
             overridden.originalForSubstitutionOverride!!
         else
             overridden
 
         processor(unwrapped)
     }
+}
 
 context(Fir2IrComponents)
 internal fun FirProperty.processOverriddenPropertySymbols(

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/generators/FakeOverrideGenerator.kt

@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.fir.backend.*
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.utils.*
 import org.jetbrains.kotlin.fir.resolve.defaultType
+import org.jetbrains.kotlin.fir.resolve.isRealOwnerOf
 import org.jetbrains.kotlin.fir.resolve.toSymbol
 import org.jetbrains.kotlin.fir.scopes.*
 import org.jetbrains.kotlin.fir.scopes.impl.FirFakeOverrideGenerator
@@ -212,7 +213,7 @@ class FakeOverrideGenerator(
     }
 
     private fun FirCallableSymbol<*>.shouldHaveComputedBaseSymbolsForClass(classLookupTag: ConeClassLikeLookupTag): Boolean =
-        fir.origin.fromSupertypes && dispatchReceiverClassLookupTagOrNull() == classLookupTag
+        fir.origin.fromSupertypes && classLookupTag.isRealOwnerOf(this)
 
     @Suppress("IncorrectFormatting")
     private inline fun <
@@ -383,7 +384,7 @@ class FakeOverrideGenerator(
 
         return scope.directOverridden(symbol).map {
             // Unwrapping should happen only for fake overrides members from the same class, not from supertypes
-            if (it.fir.isSubstitutionOverride && it.dispatchReceiverClassLookupTagOrNull() == containingClass)
+            if (it.fir.isSubstitutionOverride && containingClass.isRealOwnerOf(it))
                 it.originalForSubstitutionOverride!!
             else
                 it

compiler/fir/java/src/org/jetbrains/kotlin/fir/scopes/jvm/JvmMappedScope.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.utils.classId
 import org.jetbrains.kotlin.fir.declarations.utils.isFinal
 import org.jetbrains.kotlin.fir.resolve.defaultType
+import org.jetbrains.kotlin.fir.resolve.isRealOwnerOf
 import org.jetbrains.kotlin.fir.resolve.lookupSuperTypes
 import org.jetbrains.kotlin.fir.resolve.providers.symbolProvider
 import org.jetbrains.kotlin.fir.resolve.substitution.ConeSubstitutor
@@ -186,7 +187,7 @@ class JvmMappedScope(
         it.origin == FirDeclarationOrigin.Library
 
     private fun FirNamedFunctionSymbol.isDeclaredInMappedJavaClass(): Boolean {
-        return !fir.isSubstitutionOrIntersectionOverride && fir.dispatchReceiverClassLookupTagOrNull() == firJavaClass.symbol.toLookupTag()
+        return !fir.isSubstitutionOrIntersectionOverride && firJavaClass.symbol.toLookupTag().isRealOwnerOf(fir.symbol)
     }
 
     private fun getJdkMethodStatus(jvmDescriptor: String): JDKMemberStatus {

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ResolveUtils.kt

@@ -30,6 +30,7 @@ import org.jetbrains.kotlin.fir.scopes.FirTypeScope
 import org.jetbrains.kotlin.fir.scopes.ProcessorAction
 import org.jetbrains.kotlin.fir.scopes.impl.importedFromObjectOrStaticData
 import org.jetbrains.kotlin.fir.scopes.processOverriddenFunctions
+import org.jetbrains.kotlin.fir.symbols.ConeClassLikeLookupTag
 import org.jetbrains.kotlin.fir.symbols.FirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.symbols.lazyResolveToPhase
@@ -628,4 +629,7 @@ fun FirNamedReferenceWithCandidate.toErrorReference(diagnostic: ConeDiagnostic):
 }
 
 val FirTypeParameterSymbol.defaultType: ConeTypeParameterType
-    get() = ConeTypeParameterTypeImpl(toLookupTag(), isNullable = false)
+    get() = ConeTypeParameterTypeImpl(toLookupTag(), isNullable = false)
+
+fun ConeClassLikeLookupTag.isRealOwnerOf(declarationSymbol: FirCallableSymbol<*>): Boolean =
+    this == declarationSymbol.dispatchReceiverClassLookupTagOrNull()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/FirDataFlowAnalyzer.kt

@@ -567,11 +567,11 @@ abstract class FirDataFlowAnalyzer(
         //     return true
         // }
 
+        val ownerTag = this.toLookupTag()
         return this.unsubstitutedScope(
             session, components.scopeSession, withForcedTypeCalculator = false, memberRequiredPhase = FirResolvePhase.STATUS
         ).getFunctions(OperatorNameConventions.EQUALS).any {
-            !it.isSubstitutionOrIntersectionOverride && it.fir.isEquals(session) &&
-                    it.dispatchReceiverClassLookupTagOrNull() == this.toLookupTag()
+            !it.isSubstitutionOrIntersectionOverride && it.fir.isEquals(session) && ownerTag.isRealOwnerOf(it)
         }
     }
 

plugins/kotlinx-serialization/kotlinx-serialization.k2/src/org/jetbrains/kotlinx/serialization/compiler/fir/checkers/FirSerializationPluginClassChecker.kt

@@ -18,11 +18,11 @@ import org.jetbrains.kotlin.fir.analysis.checkers.toRegularClassSymbol
 import org.jetbrains.kotlin.fir.declarations.*
 import org.jetbrains.kotlin.fir.declarations.annotationPlatformSupport
 import org.jetbrains.kotlin.fir.declarations.utils.*
-import org.jetbrains.kotlin.fir.dispatchReceiverClassLookupTagOrNull
 import org.jetbrains.kotlin.fir.expressions.*
 import org.jetbrains.kotlin.fir.moduleData
 import org.jetbrains.kotlin.fir.resolve.defaultType
 import org.jetbrains.kotlin.fir.resolve.fullyExpandedType
+import org.jetbrains.kotlin.fir.resolve.isRealOwnerOf
 import org.jetbrains.kotlin.fir.symbols.impl.*
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.name.ClassId
@@ -453,9 +453,10 @@ object FirSerializationPluginClassChecker : FirClassChecker() {
         properties: List<FirSerializableProperty>,
         reporter: DiagnosticReporter
     ) {
+        val classLookupTag = classSymbol.toLookupTag()
         for (property in properties) {
             // Don't report anything on properties from supertypes
-            if (property.propertySymbol.dispatchReceiverClassLookupTagOrNull() != classSymbol.toLookupTag()) continue
+            if (!classLookupTag.isRealOwnerOf(property.propertySymbol)) continue
             val customSerializerType = property.serializableWith
             val serializerSymbol = customSerializerType?.toRegularClassSymbol(session)
             val propertySymbol = property.propertySymbol