diff --git a/compiler/ir/serialization.common/src/KotlinIr.proto b/compiler/ir/serialization.common/src/KotlinIr.proto
index 6a1eeb434fa..436a06aa45c 100644
--- a/compiler/ir/serialization.common/src/KotlinIr.proto
+++ b/compiler/ir/serialization.common/src/KotlinIr.proto
@@ -76,7 +76,7 @@ message FileEntry {
 }
 
 message IrFile {
-  repeated UniqId declaration_id = 1;
+  repeated int64 declaration_id = 1;
   required FileEntry file_entry = 2;
   repeated int32 fq_name = 3;
   repeated IrConstructorCall annotation = 4;
@@ -105,14 +105,12 @@ enum IrSymbolKind {
 
 message IrSymbolData {
   required IrSymbolKind kind = 1;
-  required UniqId uniq_id = 2;
-  required UniqId top_level_uniq_id = 3;
-  repeated int32 fq_name = 4;
-  optional DescriptorReference descriptor_reference = 5;
-}
 
-message IrSymbolTable {
-  repeated IrSymbolData symbols = 1;
+  required int64 uniq_id_index = 4;
+  required int64 top_level_uniq_id_index = 5;
+
+  repeated int32 fq_name = 6;
+  optional DescriptorReference descriptor_reference = 7;
 }
 
 /* ------ IrTypes --------------------------------------------- */
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/DeclarationTable.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/DeclarationTable.kt
index 79aa1632be6..46f254db482 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/DeclarationTable.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/DeclarationTable.kt
@@ -37,8 +37,10 @@ abstract class GlobalDeclarationTable(private val mangler: KotlinMangler, privat
 
     protected open fun loadKnownBuiltins(builtIns: IrBuiltIns, startIndex: Long): Long {
         var index = startIndex
+        val mask = 1L shl 63
         builtIns.knownBuiltins.forEach {
-            table[it.owner] = UniqId(index++, false).also { id -> clashTracker.commit(it.owner, id) }
+            table[it.owner] = UniqId(index or mask).also { id -> clashTracker.commit(it.owner, id) }
+            index++
         }
         return index
     }
@@ -46,7 +48,7 @@ abstract class GlobalDeclarationTable(private val mangler: KotlinMangler, privat
     open fun computeUniqIdByDeclaration(declaration: IrDeclaration): UniqId {
         return table.getOrPut(declaration) {
             with(mangler) {
-                UniqId(declaration.hashedMangle, false).also { clashTracker.commit(declaration, it) }
+                UniqId(declaration.hashedMangle).also { clashTracker.commit(declaration, it) }
             }
         }
     }
@@ -71,7 +73,7 @@ class DeclarationTable(
 
     private fun computeUniqIdByDeclaration(declaration: IrDeclaration): UniqId {
         return if (declaration.isLocalDeclaration()) {
-            table.getOrPut(declaration) { UniqId(localIndex++, true) }
+            table.getOrPut(declaration) { UniqId(localIndex++) }
         } else globalDeclarationTable.computeUniqIdByDeclaration(declaration)
     }
 
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileSerializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileSerializer.kt
index 75e5ada1ede..962c1c0b311 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileSerializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileSerializer.kt
@@ -256,11 +256,12 @@ open class IrFileSerializer(
 
         val uniqId =
             declarationTable.uniqIdByDeclaration(declaration)
-        proto.setUniqId(protoUniqId(uniqId))
+        proto.uniqIdIndex = uniqId.index
 
         val topLevelUniqId =
             declarationTable.uniqIdByDeclaration((declaration).findTopLevelDeclaration())
-        proto.setTopLevelUniqId(protoUniqId(topLevelUniqId))
+
+        proto.topLevelUniqIdIndex = topLevelUniqId.index
 
         descriptorReferenceSerializer.serializeDescriptorReference(declaration)?.let {
             proto.setDescriptorReference(it)
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinIrLinker.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinIrLinker.kt
index c65241594f1..5ea635c2893 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinIrLinker.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinIrLinker.kt
@@ -289,8 +289,8 @@ abstract class KotlinIrLinker(
             }
 
             private fun deserializeIrSymbolData(proto: ProtoSymbolData): IrSymbol {
-                val key = proto.uniqId.uniqId()
-                val topLevelKey = proto.topLevelUniqId.uniqId()
+                val key = UniqId(proto.uniqIdIndex)
+                val topLevelKey = UniqId(proto.topLevelUniqIdIndex)
 
                 val topLevelDeserializationState = getStateForID(topLevelKey)
 
@@ -409,22 +409,23 @@ abstract class KotlinIrLinker(
             fileToDeserializerMap[file] = fileDeserializer
 
             fileProto.declarationIdList.forEach {
-                val uniqId = it.uniqId()
-                assert(uniqId.isPublic)
+                val uniqId = UniqId(it)
                 moduleReversedFileIndex.getOrPut(uniqId) { fileDeserializer }
             }
 
             val forceLoadedIds = deserializationStrategy.run {
                 when {
-                    theWholeWorld -> fileProto.declarationIdList
+                    theWholeWorld -> fileProto.declarationIdList.map { UniqId(it) }
                     explicitlyExported -> fileProto.explicitlyExportedToCompilerList.map {
-                        fileDeserializer.loadSymbolData(it).topLevelUniqId
+                        fileDeserializer.loadSymbolData(it).run {
+                            UniqId(topLevelUniqIdIndex)
+                        }
                     }
                     else -> emptyList()
                 }
             }
 
-            forceLoadedIds.forEach { moduleDeserializationState.addUniqID(it.uniqId().also { i -> assert(i.isPublic) }) }
+            forceLoadedIds.forEach { moduleDeserializationState.addUniqID(it.also { i -> assert(i.isPublic) }) }
 
             return file
         }
@@ -464,9 +465,10 @@ abstract class KotlinIrLinker(
 
     private fun loadKnownBuiltinSymbols(): Long {
         var currentIndex = firstKnownBuiltinsIndex
+        val mask = 1L shl 63
         val globalDeserializedSymbols = globalDeserializationState.deserializedSymbols
         builtIns.knownBuiltins.forEach {
-            globalDeserializedSymbols[UniqId(currentIndex, isLocal = false)] = it
+            globalDeserializedSymbols[UniqId(currentIndex or mask)] = it
             assert(symbolTable.referenceSimpleFunction(it.descriptor) == it)
             currentIndex++
         }
@@ -519,7 +521,7 @@ abstract class KotlinIrLinker(
 
         val descriptorUniqId = topLevelDescriptor.getUniqId()
             ?: error("Could not get descriptor uniq id for $topLevelDescriptor")
-        val topLevelKey = UniqId(descriptorUniqId, isLocal = false)
+        val topLevelKey = UniqId(descriptorUniqId)
 
         val moduleOfOrigin = topLevelDescriptor.module
 
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinMangler.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinMangler.kt
index 97f0d691d8c..0d970f38daf 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinMangler.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/KotlinMangler.kt
@@ -28,8 +28,11 @@ interface KotlinMangler {
     }
 }
 
+private const val PUBLIC_MANGLE_FLAG = 1L shl 63
+
 abstract class KotlinManglerImpl : KotlinMangler {
-    override val String.hashMangle get() = this.cityHash64()
+
+    override val String.hashMangle get() = (this.cityHash64() % PUBLIC_MANGLE_FLAG) or PUBLIC_MANGLE_FLAG
 
     private fun hashedMangleImpl(declaration: IrDeclaration): Long {
         return declaration.uniqSymbolName().hashMangle
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/UniqId.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/UniqId.kt
index 57c00303b48..2ac291c085c 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/UniqId.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/UniqId.kt
@@ -6,30 +6,19 @@
 package org.jetbrains.kotlin.backend.common.serialization
 
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
-import org.jetbrains.kotlin.descriptors.ModuleDescriptor
 import org.jetbrains.kotlin.library.metadata.KlibMetadataProtoBuf
 import org.jetbrains.kotlin.protobuf.GeneratedMessageLite
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.*
-import org.jetbrains.kotlin.backend.common.serialization.proto.UniqId as ProtoUniqId
 
 // This is an abstract uniqIdIndex any serialized IR declarations gets.
 // It is either isLocal and then just gets and ordinary number within its module.
 // Or is visible across modules and then gets a hash of mangled name as its index.
-data class UniqId(
-    val index: Long,
-    val isLocal: Boolean
-) {
-    val isPublic: Boolean get() = !isLocal
+
+inline class UniqId(val index: Long) {
+    val isPublic: Boolean get() = (index and (1L shl 63)) != 0L
+    val isLocal: Boolean get() = (index and (1L shl 63)) == 0L
 }
 
-fun protoUniqId(uniqId: UniqId): ProtoUniqId =
-    ProtoUniqId.newBuilder()
-        .setIndex(uniqId.index)
-        .setIsLocal(uniqId.isLocal)
-        .build()
-
-fun ProtoUniqId.uniqId(): UniqId = UniqId(this.index, this.isLocal)
-
 fun <T, M : GeneratedMessageLite.ExtendableMessage<M>> M.tryGetExtension(extension: GeneratedMessageLite.GeneratedExtension<M, T>) =
     if (this.hasExtension(extension)) this.getExtension<T>(extension) else null
 
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFile.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFile.java
index 2be23b1d9ae..3ec197db75b 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFile.java
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFile.java
@@ -184,37 +184,36 @@ public final class IrFile extends
 
   private int bitField0_;
   public static final int DECLARATION_ID_FIELD_NUMBER = 1;
-  private java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.UniqId> declarationId_;
+  private java.util.List<java.lang.Long> declarationId_;
   /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+   * <code>repeated int64 declaration_id = 1;</code>
+   *
+   * <pre>
+   *  repeated UniqId declaration_id = 1;
+   * </pre>
    */
-  public java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.UniqId> getDeclarationIdList() {
+  public java.util.List<java.lang.Long>
+      getDeclarationIdList() {
     return declarationId_;
   }
   /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-   */
-  public java.util.List<? extends org.jetbrains.kotlin.backend.common.serialization.proto.UniqIdOrBuilder> 
-      getDeclarationIdOrBuilderList() {
-    return declarationId_;
-  }
-  /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+   * <code>repeated int64 declaration_id = 1;</code>
+   *
+   * <pre>
+   *  repeated UniqId declaration_id = 1;
+   * </pre>
    */
   public int getDeclarationIdCount() {
     return declarationId_.size();
   }
   /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+   * <code>repeated int64 declaration_id = 1;</code>
+   *
+   * <pre>
+   *  repeated UniqId declaration_id = 1;
+   * </pre>
    */
-  public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getDeclarationId(int index) {
-    return declarationId_.get(index);
-  }
-  /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-   */
-  public org.jetbrains.kotlin.backend.common.serialization.proto.UniqIdOrBuilder getDeclarationIdOrBuilder(
-      int index) {
+  public long getDeclarationId(int index) {
     return declarationId_.get(index);
   }
 
@@ -647,128 +646,97 @@ public final class IrFile extends
     }
     private int bitField0_;
 
-    private java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.UniqId> declarationId_ =
-      java.util.Collections.emptyList();
+    private java.util.List<java.lang.Long> declarationId_ = java.util.Collections.emptyList();
     private void ensureDeclarationIdIsMutable() {
       if (!((bitField0_ & 0x00000001) == 0x00000001)) {
-        declarationId_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.common.serialization.proto.UniqId>(declarationId_);
+        declarationId_ = new java.util.ArrayList<java.lang.Long>(declarationId_);
         bitField0_ |= 0x00000001;
        }
     }
-
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
-    public java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.UniqId> getDeclarationIdList() {
+    public java.util.List<java.lang.Long>
+        getDeclarationIdList() {
       return java.util.Collections.unmodifiableList(declarationId_);
     }
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
     public int getDeclarationIdCount() {
       return declarationId_.size();
     }
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
-    public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getDeclarationId(int index) {
+    public long getDeclarationId(int index) {
       return declarationId_.get(index);
     }
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
     public Builder setDeclarationId(
-        int index, org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (value == null) {
-        throw new NullPointerException();
-      }
+        int index, long value) {
       ensureDeclarationIdIsMutable();
       declarationId_.set(index, value);
-
+      
       return this;
     }
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
-    public Builder setDeclarationId(
-        int index, org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder builderForValue) {
-      ensureDeclarationIdIsMutable();
-      declarationId_.set(index, builderForValue.build());
-
-      return this;
-    }
-    /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-     */
-    public Builder addDeclarationId(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (value == null) {
-        throw new NullPointerException();
-      }
+    public Builder addDeclarationId(long value) {
       ensureDeclarationIdIsMutable();
       declarationId_.add(value);
-
+      
       return this;
     }
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-     */
-    public Builder addDeclarationId(
-        int index, org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (value == null) {
-        throw new NullPointerException();
-      }
-      ensureDeclarationIdIsMutable();
-      declarationId_.add(index, value);
-
-      return this;
-    }
-    /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-     */
-    public Builder addDeclarationId(
-        org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder builderForValue) {
-      ensureDeclarationIdIsMutable();
-      declarationId_.add(builderForValue.build());
-
-      return this;
-    }
-    /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-     */
-    public Builder addDeclarationId(
-        int index, org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder builderForValue) {
-      ensureDeclarationIdIsMutable();
-      declarationId_.add(index, builderForValue.build());
-
-      return this;
-    }
-    /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
     public Builder addAllDeclarationId(
-        java.lang.Iterable<? extends org.jetbrains.kotlin.backend.common.serialization.proto.UniqId> values) {
+        java.lang.Iterable<? extends java.lang.Long> values) {
       ensureDeclarationIdIsMutable();
       org.jetbrains.kotlin.protobuf.AbstractMessageLite.Builder.addAll(
           values, declarationId_);
-
+      
       return this;
     }
     /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+     * <code>repeated int64 declaration_id = 1;</code>
+     *
+     * <pre>
+     *  repeated UniqId declaration_id = 1;
+     * </pre>
      */
     public Builder clearDeclarationId() {
       declarationId_ = java.util.Collections.emptyList();
       bitField0_ = (bitField0_ & ~0x00000001);
-
-      return this;
-    }
-    /**
-     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-     */
-    public Builder removeDeclarationId(int index) {
-      ensureDeclarationIdIsMutable();
-      declarationId_.remove(index);
-
+      
       return this;
     }
 
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFileOrBuilder.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFileOrBuilder.java
index d6a538629aa..af601b92293 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFileOrBuilder.java
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrFileOrBuilder.java
@@ -8,18 +8,29 @@ public interface IrFileOrBuilder extends
     org.jetbrains.kotlin.protobuf.MessageLiteOrBuilder {
 
   /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+   * <code>repeated int64 declaration_id = 1;</code>
+   *
+   * <pre>
+   *  repeated UniqId declaration_id = 1;
+   * </pre>
    */
-  java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.UniqId> 
-      getDeclarationIdList();
+  java.util.List<java.lang.Long> getDeclarationIdList();
   /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
-   */
-  org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getDeclarationId(int index);
-  /**
-   * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId declaration_id = 1;</code>
+   * <code>repeated int64 declaration_id = 1;</code>
+   *
+   * <pre>
+   *  repeated UniqId declaration_id = 1;
+   * </pre>
    */
   int getDeclarationIdCount();
+  /**
+   * <code>repeated int64 declaration_id = 1;</code>
+   *
+   * <pre>
+   *  repeated UniqId declaration_id = 1;
+   * </pre>
+   */
+  long getDeclarationId(int index);
 
   /**
    * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.FileEntry file_entry = 2;</code>
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolData.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolData.java
index 8a9cd078fab..d6a44b78439 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolData.java
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolData.java
@@ -65,33 +65,17 @@ public final class IrSymbolData extends
             }
             break;
           }
-          case 18: {
-            org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder subBuilder = null;
-            if (((bitField0_ & 0x00000002) == 0x00000002)) {
-              subBuilder = uniqId_.toBuilder();
-            }
-            uniqId_ = input.readMessage(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.PARSER, extensionRegistry);
-            if (subBuilder != null) {
-              subBuilder.mergeFrom(uniqId_);
-              uniqId_ = subBuilder.buildPartial();
-            }
-            bitField0_ |= 0x00000002;
-            break;
-          }
-          case 26: {
-            org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder subBuilder = null;
-            if (((bitField0_ & 0x00000004) == 0x00000004)) {
-              subBuilder = topLevelUniqId_.toBuilder();
-            }
-            topLevelUniqId_ = input.readMessage(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.PARSER, extensionRegistry);
-            if (subBuilder != null) {
-              subBuilder.mergeFrom(topLevelUniqId_);
-              topLevelUniqId_ = subBuilder.buildPartial();
-            }
-            bitField0_ |= 0x00000004;
-            break;
-          }
           case 32: {
+            bitField0_ |= 0x00000002;
+            uniqIdIndex_ = input.readInt64();
+            break;
+          }
+          case 40: {
+            bitField0_ |= 0x00000004;
+            topLevelUniqIdIndex_ = input.readInt64();
+            break;
+          }
+          case 48: {
             if (!((mutable_bitField0_ & 0x00000008) == 0x00000008)) {
               fqName_ = new java.util.ArrayList<java.lang.Integer>();
               mutable_bitField0_ |= 0x00000008;
@@ -99,7 +83,7 @@ public final class IrSymbolData extends
             fqName_.add(input.readInt32());
             break;
           }
-          case 34: {
+          case 50: {
             int length = input.readRawVarint32();
             int limit = input.pushLimit(length);
             if (!((mutable_bitField0_ & 0x00000008) == 0x00000008) && input.getBytesUntilLimit() > 0) {
@@ -112,7 +96,7 @@ public final class IrSymbolData extends
             input.popLimit(limit);
             break;
           }
-          case 42: {
+          case 58: {
             org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference.Builder subBuilder = null;
             if (((bitField0_ & 0x00000008) == 0x00000008)) {
               subBuilder = descriptorReference_.toBuilder();
@@ -177,76 +161,76 @@ public final class IrSymbolData extends
     return kind_;
   }
 
-  public static final int UNIQ_ID_FIELD_NUMBER = 2;
-  private org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniqId_;
+  public static final int UNIQ_ID_INDEX_FIELD_NUMBER = 4;
+  private long uniqIdIndex_;
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+   * <code>required int64 uniq_id_index = 4;</code>
    */
-  public boolean hasUniqId() {
+  public boolean hasUniqIdIndex() {
     return ((bitField0_ & 0x00000002) == 0x00000002);
   }
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+   * <code>required int64 uniq_id_index = 4;</code>
    */
-  public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getUniqId() {
-    return uniqId_;
+  public long getUniqIdIndex() {
+    return uniqIdIndex_;
   }
 
-  public static final int TOP_LEVEL_UNIQ_ID_FIELD_NUMBER = 3;
-  private org.jetbrains.kotlin.backend.common.serialization.proto.UniqId topLevelUniqId_;
+  public static final int TOP_LEVEL_UNIQ_ID_INDEX_FIELD_NUMBER = 5;
+  private long topLevelUniqIdIndex_;
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+   * <code>required int64 top_level_uniq_id_index = 5;</code>
+   *
+   * <pre>
+   *  required bool uniq_id_locality = 5;
+   * </pre>
    */
-  public boolean hasTopLevelUniqId() {
+  public boolean hasTopLevelUniqIdIndex() {
     return ((bitField0_ & 0x00000004) == 0x00000004);
   }
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+   * <code>required int64 top_level_uniq_id_index = 5;</code>
+   *
+   * <pre>
+   *  required bool uniq_id_locality = 5;
+   * </pre>
    */
-  public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getTopLevelUniqId() {
-    return topLevelUniqId_;
+  public long getTopLevelUniqIdIndex() {
+    return topLevelUniqIdIndex_;
   }
 
-  public static final int FQ_NAME_FIELD_NUMBER = 4;
+  public static final int FQ_NAME_FIELD_NUMBER = 6;
   private java.util.List<java.lang.Integer> fqName_;
   /**
-   * <code>repeated int32 fq_name = 4;</code>
+   * <code>repeated int32 fq_name = 6;</code>
    */
   public java.util.List<java.lang.Integer>
       getFqNameList() {
     return fqName_;
   }
   /**
-   * <code>repeated int32 fq_name = 4;</code>
+   * <code>repeated int32 fq_name = 6;</code>
    */
   public int getFqNameCount() {
     return fqName_.size();
   }
   /**
-   * <code>repeated int32 fq_name = 4;</code>
+   * <code>repeated int32 fq_name = 6;</code>
    */
   public int getFqName(int index) {
     return fqName_.get(index);
   }
 
-  public static final int DESCRIPTOR_REFERENCE_FIELD_NUMBER = 5;
+  public static final int DESCRIPTOR_REFERENCE_FIELD_NUMBER = 7;
   private org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptorReference_;
   /**
-   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-   *
-   * <pre>
-   *  optional FqName fqname = 4;
-   * </pre>
+   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
    */
   public boolean hasDescriptorReference() {
     return ((bitField0_ & 0x00000008) == 0x00000008);
   }
   /**
-   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-   *
-   * <pre>
-   *  optional FqName fqname = 4;
-   * </pre>
+   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
    */
   public org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference getDescriptorReference() {
     return descriptorReference_;
@@ -254,8 +238,8 @@ public final class IrSymbolData extends
 
   private void initFields() {
     kind_ = org.jetbrains.kotlin.backend.common.serialization.proto.IrSymbolKind.FUNCTION_SYMBOL;
-    uniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
-    topLevelUniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
+    uniqIdIndex_ = 0L;
+    topLevelUniqIdIndex_ = 0L;
     fqName_ = java.util.Collections.emptyList();
     descriptorReference_ = org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference.getDefaultInstance();
   }
@@ -269,19 +253,11 @@ public final class IrSymbolData extends
       memoizedIsInitialized = 0;
       return false;
     }
-    if (!hasUniqId()) {
+    if (!hasUniqIdIndex()) {
       memoizedIsInitialized = 0;
       return false;
     }
-    if (!hasTopLevelUniqId()) {
-      memoizedIsInitialized = 0;
-      return false;
-    }
-    if (!getUniqId().isInitialized()) {
-      memoizedIsInitialized = 0;
-      return false;
-    }
-    if (!getTopLevelUniqId().isInitialized()) {
+    if (!hasTopLevelUniqIdIndex()) {
       memoizedIsInitialized = 0;
       return false;
     }
@@ -302,16 +278,16 @@ public final class IrSymbolData extends
       output.writeEnum(1, kind_.getNumber());
     }
     if (((bitField0_ & 0x00000002) == 0x00000002)) {
-      output.writeMessage(2, uniqId_);
+      output.writeInt64(4, uniqIdIndex_);
     }
     if (((bitField0_ & 0x00000004) == 0x00000004)) {
-      output.writeMessage(3, topLevelUniqId_);
+      output.writeInt64(5, topLevelUniqIdIndex_);
     }
     for (int i = 0; i < fqName_.size(); i++) {
-      output.writeInt32(4, fqName_.get(i));
+      output.writeInt32(6, fqName_.get(i));
     }
     if (((bitField0_ & 0x00000008) == 0x00000008)) {
-      output.writeMessage(5, descriptorReference_);
+      output.writeMessage(7, descriptorReference_);
     }
     output.writeRawBytes(unknownFields);
   }
@@ -328,11 +304,11 @@ public final class IrSymbolData extends
     }
     if (((bitField0_ & 0x00000002) == 0x00000002)) {
       size += org.jetbrains.kotlin.protobuf.CodedOutputStream
-        .computeMessageSize(2, uniqId_);
+        .computeInt64Size(4, uniqIdIndex_);
     }
     if (((bitField0_ & 0x00000004) == 0x00000004)) {
       size += org.jetbrains.kotlin.protobuf.CodedOutputStream
-        .computeMessageSize(3, topLevelUniqId_);
+        .computeInt64Size(5, topLevelUniqIdIndex_);
     }
     {
       int dataSize = 0;
@@ -345,7 +321,7 @@ public final class IrSymbolData extends
     }
     if (((bitField0_ & 0x00000008) == 0x00000008)) {
       size += org.jetbrains.kotlin.protobuf.CodedOutputStream
-        .computeMessageSize(5, descriptorReference_);
+        .computeMessageSize(7, descriptorReference_);
     }
     size += unknownFields.size();
     memoizedSerializedSize = size;
@@ -443,9 +419,9 @@ public final class IrSymbolData extends
       super.clear();
       kind_ = org.jetbrains.kotlin.backend.common.serialization.proto.IrSymbolKind.FUNCTION_SYMBOL;
       bitField0_ = (bitField0_ & ~0x00000001);
-      uniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
+      uniqIdIndex_ = 0L;
       bitField0_ = (bitField0_ & ~0x00000002);
-      topLevelUniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
+      topLevelUniqIdIndex_ = 0L;
       bitField0_ = (bitField0_ & ~0x00000004);
       fqName_ = java.util.Collections.emptyList();
       bitField0_ = (bitField0_ & ~0x00000008);
@@ -481,11 +457,11 @@ public final class IrSymbolData extends
       if (((from_bitField0_ & 0x00000002) == 0x00000002)) {
         to_bitField0_ |= 0x00000002;
       }
-      result.uniqId_ = uniqId_;
+      result.uniqIdIndex_ = uniqIdIndex_;
       if (((from_bitField0_ & 0x00000004) == 0x00000004)) {
         to_bitField0_ |= 0x00000004;
       }
-      result.topLevelUniqId_ = topLevelUniqId_;
+      result.topLevelUniqIdIndex_ = topLevelUniqIdIndex_;
       if (((bitField0_ & 0x00000008) == 0x00000008)) {
         fqName_ = java.util.Collections.unmodifiableList(fqName_);
         bitField0_ = (bitField0_ & ~0x00000008);
@@ -504,11 +480,11 @@ public final class IrSymbolData extends
       if (other.hasKind()) {
         setKind(other.getKind());
       }
-      if (other.hasUniqId()) {
-        mergeUniqId(other.getUniqId());
+      if (other.hasUniqIdIndex()) {
+        setUniqIdIndex(other.getUniqIdIndex());
       }
-      if (other.hasTopLevelUniqId()) {
-        mergeTopLevelUniqId(other.getTopLevelUniqId());
+      if (other.hasTopLevelUniqIdIndex()) {
+        setTopLevelUniqIdIndex(other.getTopLevelUniqIdIndex());
       }
       if (!other.fqName_.isEmpty()) {
         if (fqName_.isEmpty()) {
@@ -533,19 +509,11 @@ public final class IrSymbolData extends
         
         return false;
       }
-      if (!hasUniqId()) {
+      if (!hasUniqIdIndex()) {
         
         return false;
       }
-      if (!hasTopLevelUniqId()) {
-        
-        return false;
-      }
-      if (!getUniqId().isInitialized()) {
-        
-        return false;
-      }
-      if (!getTopLevelUniqId().isInitialized()) {
+      if (!hasTopLevelUniqIdIndex()) {
         
         return false;
       }
@@ -612,123 +580,83 @@ public final class IrSymbolData extends
       return this;
     }
 
-    private org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
+    private long uniqIdIndex_ ;
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+     * <code>required int64 uniq_id_index = 4;</code>
      */
-    public boolean hasUniqId() {
+    public boolean hasUniqIdIndex() {
       return ((bitField0_ & 0x00000002) == 0x00000002);
     }
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+     * <code>required int64 uniq_id_index = 4;</code>
      */
-    public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getUniqId() {
-      return uniqId_;
+    public long getUniqIdIndex() {
+      return uniqIdIndex_;
     }
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+     * <code>required int64 uniq_id_index = 4;</code>
      */
-    public Builder setUniqId(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (value == null) {
-        throw new NullPointerException();
-      }
-      uniqId_ = value;
-
+    public Builder setUniqIdIndex(long value) {
       bitField0_ |= 0x00000002;
+      uniqIdIndex_ = value;
+      
       return this;
     }
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+     * <code>required int64 uniq_id_index = 4;</code>
      */
-    public Builder setUniqId(
-        org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder builderForValue) {
-      uniqId_ = builderForValue.build();
-
-      bitField0_ |= 0x00000002;
-      return this;
-    }
-    /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
-     */
-    public Builder mergeUniqId(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (((bitField0_ & 0x00000002) == 0x00000002) &&
-          uniqId_ != org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance()) {
-        uniqId_ =
-          org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.newBuilder(uniqId_).mergeFrom(value).buildPartial();
-      } else {
-        uniqId_ = value;
-      }
-
-      bitField0_ |= 0x00000002;
-      return this;
-    }
-    /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
-     */
-    public Builder clearUniqId() {
-      uniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
-
+    public Builder clearUniqIdIndex() {
       bitField0_ = (bitField0_ & ~0x00000002);
+      uniqIdIndex_ = 0L;
+      
       return this;
     }
 
-    private org.jetbrains.kotlin.backend.common.serialization.proto.UniqId topLevelUniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
+    private long topLevelUniqIdIndex_ ;
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+     * <code>required int64 top_level_uniq_id_index = 5;</code>
+     *
+     * <pre>
+     *  required bool uniq_id_locality = 5;
+     * </pre>
      */
-    public boolean hasTopLevelUniqId() {
+    public boolean hasTopLevelUniqIdIndex() {
       return ((bitField0_ & 0x00000004) == 0x00000004);
     }
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+     * <code>required int64 top_level_uniq_id_index = 5;</code>
+     *
+     * <pre>
+     *  required bool uniq_id_locality = 5;
+     * </pre>
      */
-    public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getTopLevelUniqId() {
-      return topLevelUniqId_;
+    public long getTopLevelUniqIdIndex() {
+      return topLevelUniqIdIndex_;
     }
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+     * <code>required int64 top_level_uniq_id_index = 5;</code>
+     *
+     * <pre>
+     *  required bool uniq_id_locality = 5;
+     * </pre>
      */
-    public Builder setTopLevelUniqId(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (value == null) {
-        throw new NullPointerException();
-      }
-      topLevelUniqId_ = value;
-
+    public Builder setTopLevelUniqIdIndex(long value) {
       bitField0_ |= 0x00000004;
+      topLevelUniqIdIndex_ = value;
+      
       return this;
     }
     /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+     * <code>required int64 top_level_uniq_id_index = 5;</code>
+     *
+     * <pre>
+     *  required bool uniq_id_locality = 5;
+     * </pre>
      */
-    public Builder setTopLevelUniqId(
-        org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.Builder builderForValue) {
-      topLevelUniqId_ = builderForValue.build();
-
-      bitField0_ |= 0x00000004;
-      return this;
-    }
-    /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
-     */
-    public Builder mergeTopLevelUniqId(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId value) {
-      if (((bitField0_ & 0x00000004) == 0x00000004) &&
-          topLevelUniqId_ != org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance()) {
-        topLevelUniqId_ =
-          org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.newBuilder(topLevelUniqId_).mergeFrom(value).buildPartial();
-      } else {
-        topLevelUniqId_ = value;
-      }
-
-      bitField0_ |= 0x00000004;
-      return this;
-    }
-    /**
-     * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
-     */
-    public Builder clearTopLevelUniqId() {
-      topLevelUniqId_ = org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
-
+    public Builder clearTopLevelUniqIdIndex() {
       bitField0_ = (bitField0_ & ~0x00000004);
+      topLevelUniqIdIndex_ = 0L;
+      
       return this;
     }
 
@@ -740,26 +668,26 @@ public final class IrSymbolData extends
        }
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public java.util.List<java.lang.Integer>
         getFqNameList() {
       return java.util.Collections.unmodifiableList(fqName_);
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public int getFqNameCount() {
       return fqName_.size();
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public int getFqName(int index) {
       return fqName_.get(index);
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public Builder setFqName(
         int index, int value) {
@@ -769,7 +697,7 @@ public final class IrSymbolData extends
       return this;
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public Builder addFqName(int value) {
       ensureFqNameIsMutable();
@@ -778,7 +706,7 @@ public final class IrSymbolData extends
       return this;
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public Builder addAllFqName(
         java.lang.Iterable<? extends java.lang.Integer> values) {
@@ -789,7 +717,7 @@ public final class IrSymbolData extends
       return this;
     }
     /**
-     * <code>repeated int32 fq_name = 4;</code>
+     * <code>repeated int32 fq_name = 6;</code>
      */
     public Builder clearFqName() {
       fqName_ = java.util.Collections.emptyList();
@@ -800,31 +728,19 @@ public final class IrSymbolData extends
 
     private org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptorReference_ = org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference.getDefaultInstance();
     /**
-     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-     *
-     * <pre>
-     *  optional FqName fqname = 4;
-     * </pre>
+     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
      */
     public boolean hasDescriptorReference() {
       return ((bitField0_ & 0x00000010) == 0x00000010);
     }
     /**
-     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-     *
-     * <pre>
-     *  optional FqName fqname = 4;
-     * </pre>
+     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
      */
     public org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference getDescriptorReference() {
       return descriptorReference_;
     }
     /**
-     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-     *
-     * <pre>
-     *  optional FqName fqname = 4;
-     * </pre>
+     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
      */
     public Builder setDescriptorReference(org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference value) {
       if (value == null) {
@@ -836,11 +752,7 @@ public final class IrSymbolData extends
       return this;
     }
     /**
-     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-     *
-     * <pre>
-     *  optional FqName fqname = 4;
-     * </pre>
+     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
      */
     public Builder setDescriptorReference(
         org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference.Builder builderForValue) {
@@ -850,11 +762,7 @@ public final class IrSymbolData extends
       return this;
     }
     /**
-     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-     *
-     * <pre>
-     *  optional FqName fqname = 4;
-     * </pre>
+     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
      */
     public Builder mergeDescriptorReference(org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference value) {
       if (((bitField0_ & 0x00000010) == 0x00000010) &&
@@ -869,11 +777,7 @@ public final class IrSymbolData extends
       return this;
     }
     /**
-     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-     *
-     * <pre>
-     *  optional FqName fqname = 4;
-     * </pre>
+     * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
      */
     public Builder clearDescriptorReference() {
       descriptorReference_ = org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference.getDefaultInstance();
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolDataOrBuilder.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolDataOrBuilder.java
index 42fda4b16d1..a925beecf3b 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolDataOrBuilder.java
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolDataOrBuilder.java
@@ -17,50 +17,50 @@ public interface IrSymbolDataOrBuilder extends
   org.jetbrains.kotlin.backend.common.serialization.proto.IrSymbolKind getKind();
 
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+   * <code>required int64 uniq_id_index = 4;</code>
    */
-  boolean hasUniqId();
+  boolean hasUniqIdIndex();
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId uniq_id = 2;</code>
+   * <code>required int64 uniq_id_index = 4;</code>
    */
-  org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getUniqId();
+  long getUniqIdIndex();
 
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+   * <code>required int64 top_level_uniq_id_index = 5;</code>
+   *
+   * <pre>
+   *  required bool uniq_id_locality = 5;
+   * </pre>
    */
-  boolean hasTopLevelUniqId();
+  boolean hasTopLevelUniqIdIndex();
   /**
-   * <code>required .org.jetbrains.kotlin.backend.common.serialization.proto.UniqId top_level_uniq_id = 3;</code>
+   * <code>required int64 top_level_uniq_id_index = 5;</code>
+   *
+   * <pre>
+   *  required bool uniq_id_locality = 5;
+   * </pre>
    */
-  org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getTopLevelUniqId();
+  long getTopLevelUniqIdIndex();
 
   /**
-   * <code>repeated int32 fq_name = 4;</code>
+   * <code>repeated int32 fq_name = 6;</code>
    */
   java.util.List<java.lang.Integer> getFqNameList();
   /**
-   * <code>repeated int32 fq_name = 4;</code>
+   * <code>repeated int32 fq_name = 6;</code>
    */
   int getFqNameCount();
   /**
-   * <code>repeated int32 fq_name = 4;</code>
+   * <code>repeated int32 fq_name = 6;</code>
    */
   int getFqName(int index);
 
   /**
-   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-   *
-   * <pre>
-   *  optional FqName fqname = 4;
-   * </pre>
+   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
    */
   boolean hasDescriptorReference();
   /**
-   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 5;</code>
-   *
-   * <pre>
-   *  optional FqName fqname = 4;
-   * </pre>
+   * <code>optional .org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference descriptor_reference = 7;</code>
    */
   org.jetbrains.kotlin.backend.common.serialization.proto.DescriptorReference getDescriptorReference();
 }
\ No newline at end of file
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolTable.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolTable.java
index 8c16b3e0d24..b1f3660c230 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolTable.java
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/IrSymbolTable.java
@@ -476,4 +476,4 @@ public final class IrSymbolTable extends
   }
 
   // @@protoc_insertion_point(class_scope:org.jetbrains.kotlin.backend.common.serialization.proto.IrSymbolTable)
-}
+}
\ No newline at end of file
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/UniqId.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/UniqId.java
deleted file mode 100644
index 7e2847045b7..00000000000
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/UniqId.java
+++ /dev/null
@@ -1,428 +0,0 @@
-// Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: compiler/ir/serialization.common/src/KotlinIr.proto
-
-package org.jetbrains.kotlin.backend.common.serialization.proto;
-
-/**
- * Protobuf type {@code org.jetbrains.kotlin.backend.common.serialization.proto.UniqId}
- */
-public final class UniqId extends
-    org.jetbrains.kotlin.protobuf.GeneratedMessageLite implements
-    // @@protoc_insertion_point(message_implements:org.jetbrains.kotlin.backend.common.serialization.proto.UniqId)
-    UniqIdOrBuilder {
-  // Use UniqId.newBuilder() to construct.
-  private UniqId(org.jetbrains.kotlin.protobuf.GeneratedMessageLite.Builder builder) {
-    super(builder);
-    this.unknownFields = builder.getUnknownFields();
-  }
-  private UniqId(boolean noInit) { this.unknownFields = org.jetbrains.kotlin.protobuf.ByteString.EMPTY;}
-
-  private static final UniqId defaultInstance;
-  public static UniqId getDefaultInstance() {
-    return defaultInstance;
-  }
-
-  public UniqId getDefaultInstanceForType() {
-    return defaultInstance;
-  }
-
-  private final org.jetbrains.kotlin.protobuf.ByteString unknownFields;
-  private UniqId(
-      org.jetbrains.kotlin.protobuf.CodedInputStream input,
-      org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-      throws org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException {
-    initFields();
-    int mutable_bitField0_ = 0;
-    org.jetbrains.kotlin.protobuf.ByteString.Output unknownFieldsOutput =
-        org.jetbrains.kotlin.protobuf.ByteString.newOutput();
-    org.jetbrains.kotlin.protobuf.CodedOutputStream unknownFieldsCodedOutput =
-        org.jetbrains.kotlin.protobuf.CodedOutputStream.newInstance(
-            unknownFieldsOutput);
-    try {
-      boolean done = false;
-      while (!done) {
-        int tag = input.readTag();
-        switch (tag) {
-          case 0:
-            done = true;
-            break;
-          default: {
-            if (!parseUnknownField(input, unknownFieldsCodedOutput,
-                                   extensionRegistry, tag)) {
-              done = true;
-            }
-            break;
-          }
-          case 8: {
-            bitField0_ |= 0x00000001;
-            index_ = input.readUInt64();
-            break;
-          }
-          case 16: {
-            bitField0_ |= 0x00000002;
-            isLocal_ = input.readBool();
-            break;
-          }
-        }
-      }
-    } catch (org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException e) {
-      throw e.setUnfinishedMessage(this);
-    } catch (java.io.IOException e) {
-      throw new org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException(
-          e.getMessage()).setUnfinishedMessage(this);
-    } finally {
-      try {
-        unknownFieldsCodedOutput.flush();
-      } catch (java.io.IOException e) {
-      // Should not happen
-      } finally {
-        unknownFields = unknownFieldsOutput.toByteString();
-      }
-      makeExtensionsImmutable();
-    }
-  }
-  public static org.jetbrains.kotlin.protobuf.Parser<UniqId> PARSER =
-      new org.jetbrains.kotlin.protobuf.AbstractParser<UniqId>() {
-    public UniqId parsePartialFrom(
-        org.jetbrains.kotlin.protobuf.CodedInputStream input,
-        org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-        throws org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException {
-      return new UniqId(input, extensionRegistry);
-    }
-  };
-
-  @java.lang.Override
-  public org.jetbrains.kotlin.protobuf.Parser<UniqId> getParserForType() {
-    return PARSER;
-  }
-
-  private int bitField0_;
-  public static final int INDEX_FIELD_NUMBER = 1;
-  private long index_;
-  /**
-   * <code>required uint64 index = 1;</code>
-   */
-  public boolean hasIndex() {
-    return ((bitField0_ & 0x00000001) == 0x00000001);
-  }
-  /**
-   * <code>required uint64 index = 1;</code>
-   */
-  public long getIndex() {
-    return index_;
-  }
-
-  public static final int ISLOCAL_FIELD_NUMBER = 2;
-  private boolean isLocal_;
-  /**
-   * <code>required bool isLocal = 2;</code>
-   */
-  public boolean hasIsLocal() {
-    return ((bitField0_ & 0x00000002) == 0x00000002);
-  }
-  /**
-   * <code>required bool isLocal = 2;</code>
-   */
-  public boolean getIsLocal() {
-    return isLocal_;
-  }
-
-  private void initFields() {
-    index_ = 0L;
-    isLocal_ = false;
-  }
-  private byte memoizedIsInitialized = -1;
-  public final boolean isInitialized() {
-    byte isInitialized = memoizedIsInitialized;
-    if (isInitialized == 1) return true;
-    if (isInitialized == 0) return false;
-
-    if (!hasIndex()) {
-      memoizedIsInitialized = 0;
-      return false;
-    }
-    if (!hasIsLocal()) {
-      memoizedIsInitialized = 0;
-      return false;
-    }
-    memoizedIsInitialized = 1;
-    return true;
-  }
-
-  public void writeTo(org.jetbrains.kotlin.protobuf.CodedOutputStream output)
-                      throws java.io.IOException {
-    getSerializedSize();
-    if (((bitField0_ & 0x00000001) == 0x00000001)) {
-      output.writeUInt64(1, index_);
-    }
-    if (((bitField0_ & 0x00000002) == 0x00000002)) {
-      output.writeBool(2, isLocal_);
-    }
-    output.writeRawBytes(unknownFields);
-  }
-
-  private int memoizedSerializedSize = -1;
-  public int getSerializedSize() {
-    int size = memoizedSerializedSize;
-    if (size != -1) return size;
-
-    size = 0;
-    if (((bitField0_ & 0x00000001) == 0x00000001)) {
-      size += org.jetbrains.kotlin.protobuf.CodedOutputStream
-        .computeUInt64Size(1, index_);
-    }
-    if (((bitField0_ & 0x00000002) == 0x00000002)) {
-      size += org.jetbrains.kotlin.protobuf.CodedOutputStream
-        .computeBoolSize(2, isLocal_);
-    }
-    size += unknownFields.size();
-    memoizedSerializedSize = size;
-    return size;
-  }
-
-  private static final long serialVersionUID = 0L;
-  @java.lang.Override
-  protected java.lang.Object writeReplace()
-      throws java.io.ObjectStreamException {
-    return super.writeReplace();
-  }
-
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(
-      org.jetbrains.kotlin.protobuf.ByteString data)
-      throws org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException {
-    return PARSER.parseFrom(data);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(
-      org.jetbrains.kotlin.protobuf.ByteString data,
-      org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-      throws org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException {
-    return PARSER.parseFrom(data, extensionRegistry);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(byte[] data)
-      throws org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException {
-    return PARSER.parseFrom(data);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(
-      byte[] data,
-      org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-      throws org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException {
-    return PARSER.parseFrom(data, extensionRegistry);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(java.io.InputStream input)
-      throws java.io.IOException {
-    return PARSER.parseFrom(input);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(
-      java.io.InputStream input,
-      org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-      throws java.io.IOException {
-    return PARSER.parseFrom(input, extensionRegistry);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseDelimitedFrom(java.io.InputStream input)
-      throws java.io.IOException {
-    return PARSER.parseDelimitedFrom(input);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseDelimitedFrom(
-      java.io.InputStream input,
-      org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-      throws java.io.IOException {
-    return PARSER.parseDelimitedFrom(input, extensionRegistry);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(
-      org.jetbrains.kotlin.protobuf.CodedInputStream input)
-      throws java.io.IOException {
-    return PARSER.parseFrom(input);
-  }
-  public static org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parseFrom(
-      org.jetbrains.kotlin.protobuf.CodedInputStream input,
-      org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-      throws java.io.IOException {
-    return PARSER.parseFrom(input, extensionRegistry);
-  }
-
-  public static Builder newBuilder() { return Builder.create(); }
-  public Builder newBuilderForType() { return newBuilder(); }
-  public static Builder newBuilder(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId prototype) {
-    return newBuilder().mergeFrom(prototype);
-  }
-  public Builder toBuilder() { return newBuilder(this); }
-
-  /**
-   * Protobuf type {@code org.jetbrains.kotlin.backend.common.serialization.proto.UniqId}
-   */
-  public static final class Builder extends
-      org.jetbrains.kotlin.protobuf.GeneratedMessageLite.Builder<
-        org.jetbrains.kotlin.backend.common.serialization.proto.UniqId, Builder>
-      implements
-      // @@protoc_insertion_point(builder_implements:org.jetbrains.kotlin.backend.common.serialization.proto.UniqId)
-      org.jetbrains.kotlin.backend.common.serialization.proto.UniqIdOrBuilder {
-    // Construct using org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.newBuilder()
-    private Builder() {
-      maybeForceBuilderInitialization();
-    }
-
-    private void maybeForceBuilderInitialization() {
-    }
-    private static Builder create() {
-      return new Builder();
-    }
-
-    public Builder clear() {
-      super.clear();
-      index_ = 0L;
-      bitField0_ = (bitField0_ & ~0x00000001);
-      isLocal_ = false;
-      bitField0_ = (bitField0_ & ~0x00000002);
-      return this;
-    }
-
-    public Builder clone() {
-      return create().mergeFrom(buildPartial());
-    }
-
-    public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId getDefaultInstanceForType() {
-      return org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance();
-    }
-
-    public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId build() {
-      org.jetbrains.kotlin.backend.common.serialization.proto.UniqId result = buildPartial();
-      if (!result.isInitialized()) {
-        throw newUninitializedMessageException(result);
-      }
-      return result;
-    }
-
-    public org.jetbrains.kotlin.backend.common.serialization.proto.UniqId buildPartial() {
-      org.jetbrains.kotlin.backend.common.serialization.proto.UniqId result = new org.jetbrains.kotlin.backend.common.serialization.proto.UniqId(this);
-      int from_bitField0_ = bitField0_;
-      int to_bitField0_ = 0;
-      if (((from_bitField0_ & 0x00000001) == 0x00000001)) {
-        to_bitField0_ |= 0x00000001;
-      }
-      result.index_ = index_;
-      if (((from_bitField0_ & 0x00000002) == 0x00000002)) {
-        to_bitField0_ |= 0x00000002;
-      }
-      result.isLocal_ = isLocal_;
-      result.bitField0_ = to_bitField0_;
-      return result;
-    }
-
-    public Builder mergeFrom(org.jetbrains.kotlin.backend.common.serialization.proto.UniqId other) {
-      if (other == org.jetbrains.kotlin.backend.common.serialization.proto.UniqId.getDefaultInstance()) return this;
-      if (other.hasIndex()) {
-        setIndex(other.getIndex());
-      }
-      if (other.hasIsLocal()) {
-        setIsLocal(other.getIsLocal());
-      }
-      setUnknownFields(
-          getUnknownFields().concat(other.unknownFields));
-      return this;
-    }
-
-    public final boolean isInitialized() {
-      if (!hasIndex()) {
-        
-        return false;
-      }
-      if (!hasIsLocal()) {
-        
-        return false;
-      }
-      return true;
-    }
-
-    public Builder mergeFrom(
-        org.jetbrains.kotlin.protobuf.CodedInputStream input,
-        org.jetbrains.kotlin.protobuf.ExtensionRegistryLite extensionRegistry)
-        throws java.io.IOException {
-      org.jetbrains.kotlin.backend.common.serialization.proto.UniqId parsedMessage = null;
-      try {
-        parsedMessage = PARSER.parsePartialFrom(input, extensionRegistry);
-      } catch (org.jetbrains.kotlin.protobuf.InvalidProtocolBufferException e) {
-        parsedMessage = (org.jetbrains.kotlin.backend.common.serialization.proto.UniqId) e.getUnfinishedMessage();
-        throw e;
-      } finally {
-        if (parsedMessage != null) {
-          mergeFrom(parsedMessage);
-        }
-      }
-      return this;
-    }
-    private int bitField0_;
-
-    private long index_ ;
-    /**
-     * <code>required uint64 index = 1;</code>
-     */
-    public boolean hasIndex() {
-      return ((bitField0_ & 0x00000001) == 0x00000001);
-    }
-    /**
-     * <code>required uint64 index = 1;</code>
-     */
-    public long getIndex() {
-      return index_;
-    }
-    /**
-     * <code>required uint64 index = 1;</code>
-     */
-    public Builder setIndex(long value) {
-      bitField0_ |= 0x00000001;
-      index_ = value;
-      
-      return this;
-    }
-    /**
-     * <code>required uint64 index = 1;</code>
-     */
-    public Builder clearIndex() {
-      bitField0_ = (bitField0_ & ~0x00000001);
-      index_ = 0L;
-      
-      return this;
-    }
-
-    private boolean isLocal_ ;
-    /**
-     * <code>required bool isLocal = 2;</code>
-     */
-    public boolean hasIsLocal() {
-      return ((bitField0_ & 0x00000002) == 0x00000002);
-    }
-    /**
-     * <code>required bool isLocal = 2;</code>
-     */
-    public boolean getIsLocal() {
-      return isLocal_;
-    }
-    /**
-     * <code>required bool isLocal = 2;</code>
-     */
-    public Builder setIsLocal(boolean value) {
-      bitField0_ |= 0x00000002;
-      isLocal_ = value;
-      
-      return this;
-    }
-    /**
-     * <code>required bool isLocal = 2;</code>
-     */
-    public Builder clearIsLocal() {
-      bitField0_ = (bitField0_ & ~0x00000002);
-      isLocal_ = false;
-      
-      return this;
-    }
-
-    // @@protoc_insertion_point(builder_scope:org.jetbrains.kotlin.backend.common.serialization.proto.UniqId)
-  }
-
-  static {
-    defaultInstance = new UniqId(true);
-    defaultInstance.initFields();
-  }
-
-  // @@protoc_insertion_point(class_scope:org.jetbrains.kotlin.backend.common.serialization.proto.UniqId)
-}
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/UniqIdOrBuilder.java b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/UniqIdOrBuilder.java
deleted file mode 100644
index fa19da8dc32..00000000000
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/proto/UniqIdOrBuilder.java
+++ /dev/null
@@ -1,27 +0,0 @@
-// Generated by the protocol buffer compiler.  DO NOT EDIT!
-// source: compiler/ir/serialization.common/src/KotlinIr.proto
-
-package org.jetbrains.kotlin.backend.common.serialization.proto;
-
-public interface UniqIdOrBuilder extends
-    // @@protoc_insertion_point(interface_extends:org.jetbrains.kotlin.backend.common.serialization.proto.UniqId)
-    org.jetbrains.kotlin.protobuf.MessageLiteOrBuilder {
-
-  /**
-   * <code>required uint64 index = 1;</code>
-   */
-  boolean hasIndex();
-  /**
-   * <code>required uint64 index = 1;</code>
-   */
-  long getIndex();
-
-  /**
-   * <code>required bool isLocal = 2;</code>
-   */
-  boolean hasIsLocal();
-  /**
-   * <code>required bool isLocal = 2;</code>
-   */
-  boolean getIsLocal();
-}
\ No newline at end of file
diff --git a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsIrLinker.kt b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsIrLinker.kt
index 8e1961361e1..0850c8a890c 100644
--- a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsIrLinker.kt
+++ b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsIrLinker.kt
@@ -29,7 +29,7 @@ class JsIrLinker(
         JsDescriptorReferenceDeserializer(currentModule, mangler, builtIns)
 
     override fun reader(moduleDescriptor: ModuleDescriptor, fileIndex: Int, uniqId: UniqId) =
-        moduleDescriptor.kotlinLibrary.irDeclaration(uniqId.index, uniqId.isLocal, fileIndex)
+        moduleDescriptor.kotlinLibrary.irDeclaration(uniqId.index, fileIndex)
 
     override fun readSymbol(moduleDescriptor: ModuleDescriptor, fileIndex: Int, symbolIndex: Int) =
         moduleDescriptor.kotlinLibrary.symbol(symbolIndex, fileIndex)
diff --git a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsMangler.kt b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsMangler.kt
index e4d2f69cb7f..d15df74e794 100644
--- a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsMangler.kt
+++ b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsMangler.kt
@@ -11,10 +11,6 @@ import org.jetbrains.kotlin.ir.types.IrType
 import org.jetbrains.kotlin.ir.util.isInlined
 
 object JsMangler : KotlinManglerImpl() {
-    private const val MOD_VALUE = PUBLIC_LOCAL_UNIQ_ID_EDGE
-
-    override val String.hashMangle: Long get() = cityHash64() % MOD_VALUE
-
     override val IrType.isInlined: Boolean
         get() = this.isInlined()
 }
diff --git a/compiler/util-klib/src/org/jetbrains/kotlin/library/KotlinLibrary.kt b/compiler/util-klib/src/org/jetbrains/kotlin/library/KotlinLibrary.kt
index fd80b0f5e35..4c14ececa39 100644
--- a/compiler/util-klib/src/org/jetbrains/kotlin/library/KotlinLibrary.kt
+++ b/compiler/util-klib/src/org/jetbrains/kotlin/library/KotlinLibrary.kt
@@ -35,7 +35,7 @@ interface MetadataLibrary {
 
 interface IrLibrary {
     val dataFlowGraph: ByteArray?
-    fun irDeclaration(index: Long, isLocal: Boolean, fileIndex: Int): ByteArray
+    fun irDeclaration(index: Long, fileIndex: Int): ByteArray
     fun symbol(index: Int, fileIndex: Int): ByteArray
     fun type(index: Int, fileIndex: Int): ByteArray
     fun string(index: Int, fileIndex: Int): ByteArray
diff --git a/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileReaders.kt b/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileReaders.kt
index a7aaa6a2257..441859f58b1 100644
--- a/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileReaders.kt
+++ b/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileReaders.kt
@@ -169,7 +169,7 @@ abstract class IrTableReader<K>(file: File, keyReader: ByteBuffer.() -> K) {
 
 class IndexIrTableReader(file: File) : IrTableReader<Long>(file, { long })
 
-data class DeclarationId(val id: Long, val isLocal: Boolean)
+data class DeclarationId(val id: Long)
 
-class DeclarationIrTableReader(file: File) : IrTableReader<DeclarationId>(file, { DeclarationId(long, int != 0) })
-class DeclarationIrMultiTableReader(file: File) : IrMultiTableReader<DeclarationId>(file, { DeclarationId(long, int != 0) })
\ No newline at end of file
+class DeclarationIrTableReader(file: File) : IrTableReader<DeclarationId>(file, { DeclarationId(long) })
+class DeclarationIrMultiTableReader(file: File) : IrMultiTableReader<DeclarationId>(file, { DeclarationId(long) })
\ No newline at end of file
diff --git a/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileWriters.kt b/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileWriters.kt
index 75818bf65fb..15a3a49e665 100644
--- a/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileWriters.kt
+++ b/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/IrFileWriters.kt
@@ -76,7 +76,7 @@ class IrTableWriter(private val data: List<Pair<Long, ByteArray>>) : IrFileWrite
     override fun writeData(dataOutput: DataOutput) {
         dataOutput.writeInt(data.size)
 
-        var dataOffset = 4 + data.size * (8 + 4 + 4)
+        var dataOffset = Int.SIZE_BYTES + data.size * (Long.SIZE_BYTES + 2 * Int.SIZE_BYTES)
 
         data.forEach {
             dataOutput.writeLong(it.first)
@@ -91,8 +91,8 @@ class IrTableWriter(private val data: List<Pair<Long, ByteArray>>) : IrFileWrite
 
 class IrDeclarationWriter(private val declarations: List<SerializedDeclaration>) : IrFileWriter() {
 
-    private val SINGLE_INDEX_RECORD_SIZE = 20  // sizeof(Long) + 3 * sizeof(Int).
-    private val INDEX_HEADER_SIZE = 4  // sizeof(Int).
+    private val SINGLE_INDEX_RECORD_SIZE = Long.SIZE_BYTES + 2 * Int.SIZE_BYTES
+    private val INDEX_HEADER_SIZE = Int.SIZE_BYTES
 
     override fun writeData(dataOutput: DataOutput) {
         dataOutput.writeInt(declarations.size)
@@ -101,7 +101,6 @@ class IrDeclarationWriter(private val declarations: List<SerializedDeclaration>)
 
         for (d in declarations) {
             dataOutput.writeLong(d.id)
-            dataOutput.writeInt(d.local)
             dataOutput.writeInt(dataOffset)
             dataOutput.writeInt(d.size)
             dataOffset += d.size
@@ -116,8 +115,8 @@ class IrDeclarationWriter(private val declarations: List<SerializedDeclaration>)
 
 class IrMemoryDeclarationWriter(private val declarations: List<SerializedDeclaration>) : IrMemoryWriter() {
 
-    private val SINGLE_INDEX_RECORD_SIZE = 20  // sizeof(Long) + 3 * sizeof(Int).
-    private val INDEX_HEADER_SIZE = 4  // sizeof(Int).
+    private val SINGLE_INDEX_RECORD_SIZE = Long.SIZE_BYTES + 2 * Int.SIZE_BYTES
+    private val INDEX_HEADER_SIZE = Int.SIZE_BYTES
 
     override fun writeData(dataOutput: DataOutput) {
         dataOutput.writeInt(declarations.size)
@@ -126,7 +125,6 @@ class IrMemoryDeclarationWriter(private val declarations: List<SerializedDeclara
 
         for (d in declarations) {
             dataOutput.writeLong(d.id)
-            dataOutput.writeInt(d.local)
             dataOutput.writeInt(dataOffset)
             dataOutput.writeInt(d.size)
             dataOffset += d.size
diff --git a/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/KotlinLibraryImpl.kt b/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/KotlinLibraryImpl.kt
index 00abe1a594d..6a366219f33 100644
--- a/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/KotlinLibraryImpl.kt
+++ b/compiler/util-klib/src/org/jetbrains/kotlin/library/impl/KotlinLibraryImpl.kt
@@ -84,7 +84,7 @@ abstract class IrLibraryImpl(
 class IrMonoliticLibraryImpl(_access: IrLibraryAccess<IrKotlinLibraryLayout>) : IrLibraryImpl(_access) {
     override fun fileCount(): Int = files.entryCount()
 
-    override fun irDeclaration(index: Long, isLocal: Boolean, fileIndex: Int) = loadIrDeclaration(index, isLocal, fileIndex)
+    override fun irDeclaration(index: Long, fileIndex: Int) = loadIrDeclaration(index, fileIndex)
 
     override fun symbol(index: Int, fileIndex: Int) = symbols.tableItemBytes(fileIndex, index)
 
@@ -96,8 +96,8 @@ class IrMonoliticLibraryImpl(_access: IrLibraryAccess<IrKotlinLibraryLayout>) :
 
     override fun file(index: Int) = files.tableItemBytes(index)
 
-    private fun loadIrDeclaration(index: Long, isLocal: Boolean, fileIndex: Int) =
-        combinedDeclarations.tableItemBytes(fileIndex, DeclarationId(index, isLocal))
+    private fun loadIrDeclaration(index: Long, fileIndex: Int) =
+        combinedDeclarations.tableItemBytes(fileIndex, DeclarationId(index))
 
     private val combinedDeclarations: DeclarationIrMultiTableReader by lazy {
         DeclarationIrMultiTableReader(access.realFiles {
@@ -145,14 +145,14 @@ class IrPerFileLibraryImpl(_access: IrLibraryAccess<IrKotlinLibraryLayout>) : Ir
     }
 
     private val fileToDeclarationMap = mutableMapOf<Int, DeclarationIrTableReader>()
-    override fun irDeclaration(index: Long, isLocal: Boolean, fileIndex: Int): ByteArray {
+    override fun irDeclaration(index: Long, fileIndex: Int): ByteArray {
         val dataReader = fileToDeclarationMap.getOrPut(fileIndex) {
             val fileDirectory = directories[fileIndex]
             DeclarationIrTableReader(access.realFiles {
                 it.irDeclarations(fileDirectory)
             })
         }
-        return dataReader.tableItemBytes(DeclarationId(index, isLocal))
+        return dataReader.tableItemBytes(DeclarationId(index))
     }
 
     private val fileToSymbolMap = mutableMapOf<Int, IrArrayReader>()