diff --git a/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/impl/KotlinStaticDeclarationProvider.kt b/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/impl/KotlinStaticDeclarationProvider.kt
index 54b6872715f..d3ff716822b 100644
--- a/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/impl/KotlinStaticDeclarationProvider.kt
+++ b/analysis/analysis-api-providers/src/org/jetbrains/kotlin/analysis/providers/impl/KotlinStaticDeclarationProvider.kt
@@ -17,10 +17,11 @@ import com.intellij.psi.PsiManager
 import com.intellij.psi.SingleRootFileViewProvider
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.stubs.StubElement
-import com.intellij.util.containers.CollectionFactory
+import com.intellij.util.containers.CollectionFactory.createConcurrentWeakValueMap
 import com.intellij.util.indexing.FileContent
 import com.intellij.util.indexing.FileContentImpl
 import com.intellij.util.io.URLUtil
+import java.util.concurrent.ConcurrentHashMap
 import org.jetbrains.kotlin.analysis.decompiler.psi.KotlinBuiltInDecompiler
 import org.jetbrains.kotlin.analysis.decompiler.stub.file.ClsKotlinBinaryClassCache
 import org.jetbrains.kotlin.analysis.decompiler.stub.file.KotlinClsStubBuilder
@@ -306,35 +307,30 @@ public class KotlinStaticDeclarationProviderFactory(
         val binaryClassCache = ClsKotlinBinaryClassCache.getInstance()
         for (root in additionalRoots) {
             KotlinFakeClsStubsCache.processAdditionalRoot(root) { additionalRoot ->
-                val stubs = mutableListOf<KotlinFileStubImpl>()
+                val stubs = hashMapOf<VirtualFile, KotlinFileStubImpl>()
                 VfsUtilCore.visitChildrenRecursively(additionalRoot, object : VirtualFileVisitor<Void>() {
                     override fun visitFile(file: VirtualFile): Boolean {
                         if (!file.isDirectory) {
                             val fileContent = FileContentImpl.createByFile(file)
-                            if (!binaryClassCache.isKotlinJvmCompiledFile(file, fileContent.content)) return true
-                            val stub: KotlinFileStubImpl = when {
-                                file.fileType == JavaClassFileType.INSTANCE -> {
-                                    if (!binaryClassCache.isKotlinJvmCompiledFile(file, fileContent.content)) return true
-                                    KotlinClsStubBuilder().buildFileStub(fileContent) as? KotlinFileStubImpl ?: return true
-                                }
-                                file.extension == BuiltInSerializerProtocol.BUILTINS_FILE_EXTENSION -> {
-                                    if (!builtins.add(file.name)) return true
-                                    builtInDecompiler.stubBuilder.buildFileStub(fileContent) as? KotlinFileStubImpl ?: return true
-                                }
-                                else -> return true
+                            if (binaryClassCache.isKotlinJvmCompiledFile(file, fileContent.content) &&
+                                file.fileType == JavaClassFileType.INSTANCE
+                            ) {
+                                (KotlinClsStubBuilder().buildFileStub(fileContent) as? KotlinFileStubImpl)?.let { stubs.put(file, it) }
                             }
-                            val fakeFile = object : KtFile(KtClassFileViewProvider(psiManager, fileContent.file), isCompiled = true) {
-                                override fun getStub() = stub
-                                override fun isPhysical() = false
-                            }
-                            stub.psi = fakeFile
-                            stubs.add(stub)
                         }
                         return true
                     }
                 })
                 stubs
-            }?.forEach { processStub(it) }
+            }?.forEach { entry ->
+                val stub = entry.value
+                val fakeFile = object : KtFile(KtClassFileViewProvider(psiManager, entry.key), isCompiled = true) {
+                    override fun getStub() = stub
+                    override fun isPhysical() = false
+                }
+                stub.psi = fakeFile
+                processStub(stub)
+            }
         }
 
         // Indexing user source files
@@ -354,10 +350,13 @@ public class KotlinStaticDeclarationProviderFactory(
  * Otherwise, each test would start indexing of stdlib from scratch,
  * and under the lock which makes tests extremely slow*/
 public class KotlinFakeClsStubsCache {
-    private val fakeFileClsStubs = CollectionFactory.createConcurrentWeakValueMap<String, List<KotlinFileStubImpl>>()
+    private val fakeFileClsStubs = ConcurrentHashMap<String, Map<VirtualFile, KotlinFileStubImpl>>()
 
     public companion object {
-        public fun processAdditionalRoot(root: VirtualFile, storage: (VirtualFile) -> List<KotlinFileStubImpl>): List<KotlinFileStubImpl>? {
+        public fun processAdditionalRoot(
+            root: VirtualFile,
+            storage: (VirtualFile) -> Map<VirtualFile, KotlinFileStubImpl>
+        ): Map<VirtualFile, KotlinFileStubImpl>? {
             val service = ApplicationManager.getApplication().getService(KotlinFakeClsStubsCache::class.java) ?: return null
             if (service.fakeFileClsStubs[root.path] == null) {
                 service.fakeFileClsStubs[root.path] = storage(root)