diff --git a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt
index 1887cc5b8c2..0931b7c9bfc 100644
--- a/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt
+++ b/compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/ic/invalidation.kt
@@ -6,7 +6,8 @@
 package org.jetbrains.kotlin.ir.backend.js.ic
 
 import org.jetbrains.kotlin.backend.common.serialization.IdSignatureDeserializer
-import org.jetbrains.kotlin.backend.common.serialization.IrLibraryFile
+import org.jetbrains.kotlin.backend.common.serialization.IrLibraryBytesSource
+import org.jetbrains.kotlin.backend.common.serialization.IrLibraryFileFromBytes
 import org.jetbrains.kotlin.backend.common.serialization.codedInputStream
 import org.jetbrains.kotlin.backend.common.serialization.signature.IdSignatureDescriptor
 import org.jetbrains.kotlin.config.CompilerConfiguration
@@ -121,7 +122,7 @@ private fun KotlinLibrary.filesAndSigReaders(): List<Pair<String, IdSignatureDes
     for (i in 0 until fileSize) {
         val fileStream = file(i).codedInputStream
         val fileProto = ProtoFile.parseFrom(fileStream, extReg)
-        val sigReader = IdSignatureDeserializer(object : IrLibraryFile() {
+        val sigReader = IdSignatureDeserializer(IrLibraryFileFromBytes(object : IrLibraryBytesSource() {
             private fun err(): Nothing = error("Not supported")
             override fun irDeclaration(index: Int): ByteArray = err()
 
@@ -134,7 +135,7 @@ private fun KotlinLibrary.filesAndSigReaders(): List<Pair<String, IdSignatureDes
             override fun body(index: Int): ByteArray = err()
 
             override fun debugInfo(index: Int): ByteArray? = null
-        }, null)
+        }), null)
 
         result.add(fileProto.fileEntry.name to sigReader)
     }
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/BasicIrModuleDeserializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/BasicIrModuleDeserializer.kt
index 60b945d94ee..18ab4ea3d14 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/BasicIrModuleDeserializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/BasicIrModuleDeserializer.kt
@@ -104,7 +104,7 @@ abstract class BasicIrModuleDeserializer(
 
     private fun deserializeIrFile(fileProto: ProtoFile, fileIndex: Int, moduleDeserializer: IrModuleDeserializer, allowErrorNodes: Boolean): IrFile {
 
-        val fileReader = IrLibraryFileFromKlib(moduleDeserializer.klib, fileIndex)
+        val fileReader = IrLibraryFileFromBytes(IrKlibBytesSource(moduleDeserializer.klib, fileIndex))
         val file = fileReader.createFile(moduleFragment, fileProto)
         val fileStrategy = strategyResolver(file.fileEntry.name)
 
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IdSignatureDeserializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IdSignatureDeserializer.kt
index 7a0ea83646a..a19fa494a12 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IdSignatureDeserializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IdSignatureDeserializer.kt
@@ -8,8 +8,6 @@ package org.jetbrains.kotlin.backend.common.serialization
 import org.jetbrains.kotlin.ir.symbols.IrFileSymbol
 import org.jetbrains.kotlin.ir.util.IdSignature
 import org.jetbrains.kotlin.ir.util.IdSignature.FileSignature
-import org.jetbrains.kotlin.protobuf.CodedInputStream
-import org.jetbrains.kotlin.protobuf.ExtensionRegistryLite
 import org.jetbrains.kotlin.backend.common.serialization.proto.AccessorIdSignature as ProtoAccessorIdSignature
 import org.jetbrains.kotlin.backend.common.serialization.proto.CommonIdSignature as ProtoCommonIdSignature
 import org.jetbrains.kotlin.backend.common.serialization.proto.CompositeSignature as ProtoCompositeSignature
@@ -19,14 +17,12 @@ import org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature as Pr
 import org.jetbrains.kotlin.backend.common.serialization.proto.LocalSignature as ProtoLocalSignature
 import org.jetbrains.kotlin.backend.common.serialization.proto.LoweredIdSignature as ProtoLoweredIdSignature
 
-class IdSignatureDeserializer(private val fileReader: IrLibraryFile, fileSymbol: IrFileSymbol?) {
-
-    private fun readSignature(index: Int): CodedInputStream = fileReader.signature(index).codedInputStream
+class IdSignatureDeserializer(private val libraryFile: IrLibraryFile, fileSymbol: IrFileSymbol?) {
 
     private val fileSignature: FileSignature? = fileSymbol?.let { FileSignature(it) }
 
     private fun loadSignatureProto(index: Int): ProtoIdSignature {
-        return ProtoIdSignature.parseFrom(readSignature(index), extensionRegistryLite)
+        return libraryFile.signature(index)
     }
 
     private val signatureCache = HashMap<Int, IdSignature>()
@@ -39,8 +35,8 @@ class IdSignatureDeserializer(private val fileReader: IrLibraryFile, fileSymbol:
     }
 
     private fun deserializePublicIdSignature(proto: ProtoCommonIdSignature): IdSignature.CommonSignature {
-        val pkg = fileReader.deserializeFqName(proto.packageFqNameList)
-        val cls = fileReader.deserializeFqName(proto.declarationFqNameList)
+        val pkg = libraryFile.deserializeFqName(proto.packageFqNameList)
+        val cls = libraryFile.deserializeFqName(proto.declarationFqNameList)
         val memberId = if (proto.hasMemberUniqId()) proto.memberUniqId else null
 
         return IdSignature.CommonSignature(pkg, cls, memberId, proto.flags)
@@ -49,7 +45,7 @@ class IdSignatureDeserializer(private val fileReader: IrLibraryFile, fileSymbol:
     private fun deserializeAccessorIdSignature(proto: ProtoAccessorIdSignature): IdSignature.AccessorSignature {
         val propertySignature = deserializeIdSignature(proto.propertySignature)
         require(propertySignature is IdSignature.CommonSignature) { "For public accessor corresponding property supposed to be public as well" }
-        val name = fileReader.deserializeString(proto.name)
+        val name = libraryFile.string(proto.name)
         val hash = proto.accessorHashId
         val mask = proto.flags
 
@@ -78,9 +74,9 @@ class IdSignatureDeserializer(private val fileReader: IrLibraryFile, fileSymbol:
     }
 
     private fun deserializeLocalIdSignature(proto: ProtoLocalSignature): IdSignature.LocalSignature {
-        val localFqn = fileReader.deserializeFqName(proto.localFqNameList)
+        val localFqn = libraryFile.deserializeFqName(proto.localFqNameList)
         val localHash = if (proto.hasLocalHash()) proto.localHash else null
-        val description = if (proto.hasDebugInfo()) fileReader.deserializeDebugInfo(proto.debugInfo) else null
+        val description = if (proto.hasDebugInfo()) libraryFile.debugInfo(proto.debugInfo) else null
         return IdSignature.LocalSignature(localFqn, localHash, description)
     }
 
@@ -105,8 +101,4 @@ class IdSignatureDeserializer(private val fileReader: IrLibraryFile, fileSymbol:
     fun signatureToIndexMapping(): Map<IdSignature, Int> {
         return signatureCache.entries.associate { it.value to it.key }
     }
-
-    companion object {
-        private val extensionRegistryLite = ExtensionRegistryLite.newInstance()
-    }
 }
\ No newline at end of file
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrBodyDeserializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrBodyDeserializer.kt
index eab40901871..f3114be1d42 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrBodyDeserializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrBodyDeserializer.kt
@@ -78,7 +78,7 @@ class IrBodyDeserializer(
     private val builtIns: IrBuiltIns,
     private val allowErrorNodes: Boolean,
     private val irFactory: IrFactory,
-    private val fileReader: IrLibraryFile,
+    private val libraryFile: IrLibraryFile,
     private val declarationDeserializer: IrDeclarationDeserializer,
     private val statementOriginIndex: Map<String, IrStatementOrigin>,
     private val allowErrorStatementOrigins: Boolean, // TODO: support InlinerExpressionLocationHint
@@ -382,9 +382,9 @@ class IrBodyDeserializer(
         start: Int, end: Int, type: IrType
     ): IrErrorExpression {
         require(allowErrorNodes) {
-            "IrErrorExpression($start, $end, \"${fileReader.deserializeString(proto.description)}\") found but error code is not allowed"
+            "IrErrorExpression($start, $end, \"${libraryFile.string(proto.description)}\") found but error code is not allowed"
         }
-        return IrErrorExpressionImpl(start, end, type, fileReader.deserializeString(proto.description))
+        return IrErrorExpressionImpl(start, end, type, libraryFile.string(proto.description))
     }
 
     private fun deserializeErrorCallExpression(
@@ -392,9 +392,9 @@ class IrBodyDeserializer(
         start: Int, end: Int, type: IrType
     ): IrErrorCallExpression {
         require(allowErrorNodes) {
-            "IrErrorCallExpressionImpl($start, $end, \"${fileReader.deserializeString(proto.description)}\") found but error code is not allowed"
+            "IrErrorCallExpressionImpl($start, $end, \"${libraryFile.string(proto.description)}\") found but error code is not allowed"
         }
-        return IrErrorCallExpressionImpl(start, end, type, fileReader.deserializeString(proto.description)).apply {
+        return IrErrorCallExpressionImpl(start, end, type, libraryFile.string(proto.description)).apply {
             if (proto.hasReceiver()) {
                 explicitReceiver = deserializeExpression(proto.receiver)
             }
@@ -672,7 +672,7 @@ class IrBodyDeserializer(
     }
 
     private fun deserializeLoop(proto: ProtoLoop, loop: IrLoop): IrLoop {
-        val label = if (proto.hasLabel()) fileReader.deserializeString(proto.label) else null
+        val label = if (proto.hasLabel()) libraryFile.string(proto.label) else null
         val body = if (proto.hasBody()) deserializeExpression(proto.body) else null
         val condition = deserializeExpression(proto.condition)
 
@@ -713,7 +713,7 @@ class IrBodyDeserializer(
             start,
             end,
             type,
-            fileReader.deserializeString(proto.memberName),
+            libraryFile.string(proto.memberName),
             deserializeExpression(proto.receiver)
         )
 
@@ -774,7 +774,7 @@ class IrBodyDeserializer(
         }
 
     private fun deserializeBreak(proto: ProtoBreak, start: Int, end: Int, type: IrType): IrBreak {
-        val label = if (proto.hasLabel()) fileReader.deserializeString(proto.label) else null
+        val label = if (proto.hasLabel()) libraryFile.string(proto.label) else null
         val loopId = proto.loopId
         val loop = deserializeLoopHeader(loopId) {
             if (allowErrorLoopIndices) {
@@ -790,7 +790,7 @@ class IrBodyDeserializer(
     }
 
     private fun deserializeContinue(proto: ProtoContinue, start: Int, end: Int, type: IrType): IrContinue {
-        val label = if (proto.hasLabel()) fileReader.deserializeString(proto.label) else null
+        val label = if (proto.hasLabel()) libraryFile.string(proto.label) else null
         val loopId = proto.loopId
         val loop = deserializeLoopHeader(loopId) {
             if (allowErrorLoopIndices) {
@@ -822,7 +822,7 @@ class IrBodyDeserializer(
             LONG
             -> IrConstImpl.long(start, end, type, proto.long)
             STRING
-            -> IrConstImpl.string(start, end, type, fileReader.deserializeString(proto.string))
+            -> IrConstImpl.string(start, end, type, libraryFile.string(proto.string))
             FLOAT_BITS
             -> IrConstImpl.float(start, end, type, Float.fromBits(proto.floatBits))
             DOUBLE_BITS
@@ -891,7 +891,7 @@ class IrBodyDeserializer(
     }
 
     fun deserializeIrStatementOrigin(protoName: Int): IrStatementOrigin {
-        return fileReader.deserializeString(protoName).let {
+        return libraryFile.string(protoName).let {
             val componentPrefix = "COMPONENT_"
             when {
                 it.startsWith(componentPrefix) -> {
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrDeclarationDeserializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrDeclarationDeserializer.kt
index 078cd80e769..e67e611bd8d 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrDeclarationDeserializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrDeclarationDeserializer.kt
@@ -27,8 +27,6 @@ import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.types.impl.*
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.name.Name
-import org.jetbrains.kotlin.protobuf.CodedInputStream
-import org.jetbrains.kotlin.protobuf.ExtensionRegistryLite
 import org.jetbrains.kotlin.types.Variance
 import kotlin.collections.set
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrAnonymousInit as ProtoAnonymousInit
@@ -61,7 +59,7 @@ class IrDeclarationDeserializer(
     builtIns: IrBuiltIns,
     private val symbolTable: SymbolTable,
     val irFactory: IrFactory,
-    private val fileReader: IrLibraryFile,
+    private val libraryFile: IrLibraryFile,
     private val parent: IrDeclarationParent,
     val allowErrorNodes: Boolean,
     private val deserializeInlineFunctions: Boolean,
@@ -81,7 +79,7 @@ class IrDeclarationDeserializer(
         builtIns,
         allowErrorNodes,
         irFactory,
-        fileReader,
+        libraryFile,
         this,
         statementOriginIndex + additionalStatementOriginIndex,
         allowErrorStatementOrigins,
@@ -89,17 +87,14 @@ class IrDeclarationDeserializer(
     )
 
     private fun deserializeName(index: Int): Name {
-        val name = fileReader.deserializeString(index)
+        val name = libraryFile.string(index)
         return Name.guessByFirstCharacter(name)
     }
 
     private val irTypeCache = mutableMapOf<Int, IrType>()
 
-    private fun readType(index: Int): CodedInputStream =
-        fileReader.type(index).codedInputStream
-
     private fun loadTypeProto(index: Int): ProtoType {
-        return ProtoType.parseFrom(readType(index), extensionRegistry)
+        return libraryFile.type(index)
     }
 
     fun deserializeNullableIrType(index: Int): IrType? = if (index == -1) null else deserializeIrType(index)
@@ -485,15 +480,12 @@ class IrDeclarationDeserializer(
         }
     }
 
-    private fun readBody(index: Int): CodedInputStream =
-        fileReader.body(index).codedInputStream
-
     private fun loadStatementBodyProto(index: Int): ProtoStatement {
-        return ProtoStatement.parseFrom(readBody(index), extensionRegistry)
+        return libraryFile.statementBody(index)
     }
 
     private fun loadExpressionBodyProto(index: Int): ProtoExpression {
-        return ProtoExpression.parseFrom(readBody(index), extensionRegistry)
+        return libraryFile.expressionBody(index)
     }
 
     fun deserializeExpressionBody(index: Int): IrExpressionBody? {
@@ -748,12 +740,10 @@ class IrDeclarationDeserializer(
         private val allKnownStatementOrigins = IrStatementOrigin::class.nestedClasses.toList()
         private val statementOriginIndex =
             allKnownStatementOrigins.mapNotNull { it.objectInstance as? IrStatementOriginImpl }.associateBy { it.debugName }
-
-        private val extensionRegistry = ExtensionRegistryLite.newInstance()
     }
 
     fun deserializeIrDeclarationOrigin(protoName: Int): IrDeclarationOriginImpl {
-        val originName = fileReader.deserializeString(protoName)
+        val originName = libraryFile.string(protoName)
         return declarationOriginIndex[originName] ?: object : IrDeclarationOriginImpl(originName) {}
     }
 
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileDeserializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileDeserializer.kt
index 11d5500fcd9..a602ba23966 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileDeserializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrFileDeserializer.kt
@@ -16,15 +16,18 @@ import org.jetbrains.kotlin.ir.util.NaiveSourceBasedFileEntryImpl
 import org.jetbrains.kotlin.library.IrLibrary
 import org.jetbrains.kotlin.library.encodings.WobblyTF8
 import org.jetbrains.kotlin.name.FqName
-import org.jetbrains.kotlin.protobuf.CodedInputStream
 import org.jetbrains.kotlin.protobuf.ExtensionRegistryLite
+import org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature as ProtoIdSignature
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrConstructorCall as ProtoConstructorCall
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrDeclaration as ProtoDeclaration
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrExpression as ProtoExpression
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrFile as ProtoFile
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrStatement as ProtoStatement
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrType as ProtoType
 
 class IrFileDeserializer(
     val file: IrFile,
-    private val fileReader: IrLibraryFile,
+    private val libraryFile: IrLibraryFile,
     fileProto: ProtoFile,
     val symbolDeserializer: IrSymbolDeserializer,
     val declarationDeserializer: IrDeclarationDeserializer,
@@ -39,12 +42,9 @@ class IrFileDeserializer(
         }
     }
 
-    private fun readDeclaration(index: Int): CodedInputStream =
-        fileReader.irDeclaration(index).codedInputStream
-
     private fun loadTopLevelDeclarationProto(idSig: IdSignature): ProtoDeclaration {
         val idSigIndex = reversedSignatureIndex[idSig] ?: error("Not found Idx for $idSig")
-        return ProtoDeclaration.parseFrom(readDeclaration(idSigIndex), ExtensionRegistryLite.newInstance())
+        return libraryFile.declaration(idSigIndex)
     }
 
     fun deserializeFileImplicitDataIfFirstUse() {
@@ -58,7 +58,7 @@ class IrFileDeserializer(
 class FileDeserializationState(
     val linker: KotlinIrLinker,
     file: IrFile,
-    fileReader: IrLibraryFile,
+    fileReader: IrLibraryFileFromBytes,
     fileProto: ProtoFile,
     deserializeBodies: Boolean,
     allowErrorNodes: Boolean,
@@ -139,6 +139,16 @@ class FileDeserializationState(
 }
 
 abstract class IrLibraryFile {
+    abstract fun declaration(index: Int): ProtoDeclaration
+    abstract fun type(index: Int): ProtoType
+    abstract fun signature(index: Int): ProtoIdSignature
+    abstract fun string(index: Int): String
+    abstract fun expressionBody(index: Int): ProtoExpression
+    abstract fun statementBody(index: Int): ProtoStatement
+    abstract fun debugInfo(index: Int): String?
+}
+
+abstract class IrLibraryBytesSource {
     abstract fun irDeclaration(index: Int): ByteArray
     abstract fun type(index: Int): ByteArray
     abstract fun signature(index: Int): ByteArray
@@ -147,7 +157,32 @@ abstract class IrLibraryFile {
     abstract fun debugInfo(index: Int): ByteArray?
 }
 
-class IrLibraryFileFromKlib(private val klib: IrLibrary, private val fileIndex: Int) : IrLibraryFile() {
+class IrLibraryFileFromBytes(private val bytesSource: IrLibraryBytesSource) : IrLibraryFile() {
+
+    override fun declaration(index: Int): ProtoDeclaration =
+        ProtoDeclaration.parseFrom(bytesSource.irDeclaration(index).codedInputStream, extensionRegistryLite)
+
+    override fun type(index: Int): ProtoType = ProtoType.parseFrom(bytesSource.type(index).codedInputStream, extensionRegistryLite)
+
+    override fun signature(index: Int): ProtoIdSignature =
+        ProtoIdSignature.parseFrom(bytesSource.signature(index).codedInputStream, extensionRegistryLite)
+
+    override fun string(index: Int): String = WobblyTF8.decode(bytesSource.string(index))
+
+    override fun expressionBody(index: Int): ProtoExpression =
+        ProtoExpression.parseFrom(bytesSource.body(index).codedInputStream, extensionRegistryLite)
+
+    override fun statementBody(index: Int): ProtoStatement =
+        ProtoStatement.parseFrom(bytesSource.body(index).codedInputStream, extensionRegistryLite)
+
+    override fun debugInfo(index: Int): String? = bytesSource.debugInfo(index)?.let { WobblyTF8.decode(it) }
+
+    companion object {
+        val extensionRegistryLite: ExtensionRegistryLite = ExtensionRegistryLite.newInstance()
+    }
+}
+
+class IrKlibBytesSource(private val klib: IrLibrary, private val fileIndex: Int) : IrLibraryBytesSource() {
     override fun irDeclaration(index: Int): ByteArray = klib.irDeclaration(index, fileIndex)
     override fun type(index: Int): ByteArray = klib.type(index, fileIndex)
     override fun signature(index: Int): ByteArray = klib.signature(index, fileIndex)
@@ -156,11 +191,8 @@ class IrLibraryFileFromKlib(private val klib: IrLibrary, private val fileIndex:
     override fun debugInfo(index: Int): ByteArray? = klib.debugInfo(index, fileIndex)
 }
 
-internal fun IrLibraryFile.deserializeString(index: Int): String = WobblyTF8.decode(string(index))
-internal fun IrLibraryFile.deserializeDebugInfo(index: Int): String? = debugInfo(index)?.let { WobblyTF8.decode(it) }
-
 internal fun IrLibraryFile.deserializeFqName(fqn: List<Int>): String =
-    fqn.joinToString(".", transform = ::deserializeString)
+    fqn.joinToString(".", transform = ::string)
 
 fun IrLibraryFile.createFile(module: IrModuleFragment, fileProto: ProtoFile): IrFile {
     val fileName = fileProto.fileEntry.name
diff --git a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrSymbolDeserializer.kt b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrSymbolDeserializer.kt
index 31995ad7524..95b7beeeec4 100644
--- a/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrSymbolDeserializer.kt
+++ b/compiler/ir/serialization.common/src/org/jetbrains/kotlin/backend/common/serialization/IrSymbolDeserializer.kt
@@ -20,7 +20,7 @@ import org.jetbrains.kotlin.ir.util.ReferenceSymbolTable
 
 class IrSymbolDeserializer(
     val symbolTable: ReferenceSymbolTable,
-    val fileReader: IrLibraryFile,
+    val libraryFile: IrLibraryFile,
     val fileSymbol: IrFileSymbol,
     val actuals: List<Actual>,
     val enqueueLocalTopLevelDeclaration: (IdSignature) -> Unit,
@@ -103,7 +103,7 @@ class IrSymbolDeserializer(
         }
     }
 
-    val signatureDeserializer = IdSignatureDeserializer(fileReader, fileSymbol)
+    val signatureDeserializer = IdSignatureDeserializer(libraryFile, fileSymbol)
 
     fun deserializeIdSignature(index: Int): IdSignature {
         return signatureDeserializer.deserializeIdSignature(index)
diff --git a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcFileDeserializer.kt b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcFileDeserializer.kt
index 8a03f988ef5..4da7f83382b 100644
--- a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcFileDeserializer.kt
+++ b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcFileDeserializer.kt
@@ -23,13 +23,12 @@ import org.jetbrains.kotlin.library.impl.DeclarationIrTableMemoryReader
 import org.jetbrains.kotlin.library.impl.IrArrayMemoryReader
 import org.jetbrains.kotlin.library.impl.IrLongArrayMemoryReader
 import org.jetbrains.kotlin.protobuf.ExtensionRegistryLite
-import org.jetbrains.kotlin.backend.common.serialization.proto.IrDeclaration as ProtoIrDeclaration
 import org.jetbrains.kotlin.backend.common.serialization.proto.IrFile as ProtoIrFile
 
 class IcFileDeserializer(
     val linker: JsIrLinker,
     private val file: IrFile,
-    originalFileReader: IrLibraryFile,
+    originalFileReader: IrLibraryFileFromBytes,
     fileProto: ProtoIrFile,
     deserializeBodies: Boolean,
     allowErrorNodes: Boolean,
@@ -115,7 +114,7 @@ class IcFileDeserializer(
 
     // IC data processing starts here
 
-    private val icFileReader = FileReaderFromSerializedIrFile(icFileData.file)
+    private val icFileReader = IrLibraryFileFromBytes(FileReaderFromSerializedIrFile(icFileData.file))
 
     val symbolDeserializer = IrSymbolDeserializer(
         linker.symbolTable,
@@ -195,8 +194,7 @@ class IcFileDeserializer(
         cachedDeclaration(idSig)?.let { return it }
 
         val idSigIndex = reversedSignatureIndex[idSig] ?: return null
-        val declarationStream = icFileReader.irDeclaration(idSigIndex).codedInputStream
-        val declarationProto = ProtoIrDeclaration.parseFrom(declarationStream, extensionRegistryLite)
+        val declarationProto = icFileReader.declaration(idSigIndex)
         return declarationDeserializer.deserializeDeclaration(declarationProto)
     }
 
@@ -221,8 +219,7 @@ class IcFileDeserializer(
         }
 
         reversedSignatureIndex[maybeTopLevel]?.let { idSigIndex ->
-            val declarationStream = icFileReader.irDeclaration(idSigIndex).codedInputStream
-            val declarationProto = ProtoIrDeclaration.parseFrom(declarationStream, extensionRegistryLite)
+            val declarationProto = icFileReader.declaration(idSigIndex)
             return declarationDeserializer.deserializeDeclaration(declarationProto)
         }
 
@@ -250,9 +247,7 @@ class IcFileDeserializer(
     }
 }
 
-private val extensionRegistryLite = ExtensionRegistryLite.newInstance()
-
-private class FileReaderFromSerializedIrFile(val irFile: SerializedIrFile) : IrLibraryFile() {
+private class FileReaderFromSerializedIrFile(val irFile: SerializedIrFile) : IrLibraryBytesSource() {
     private val declarationReader = DeclarationIrTableMemoryReader(irFile.declarations)
     private val typeReader = IrArrayMemoryReader(irFile.types)
     private val signatureReader = IrArrayMemoryReader(irFile.signatures)
diff --git a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcModuleDeserializer.kt b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcModuleDeserializer.kt
index f467cf44a07..75dea07d9c6 100644
--- a/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcModuleDeserializer.kt
+++ b/compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcModuleDeserializer.kt
@@ -127,7 +127,7 @@ class IcModuleDeserializer(
         allowErrorNodes: Boolean
     ): IrFile {
 
-        val fileReader = IrLibraryFileFromKlib(moduleDeserializer.klib, fileIndex)
+        val fileReader = IrLibraryFileFromBytes(IrKlibBytesSource(moduleDeserializer.klib, fileIndex))
         val file = fileReader.createFile(moduleFragment, fileProto)
         val fileStrategy = strategyResolver(file.fileEntry.name)
 
diff --git a/compiler/ir/serialization.jvm/src/JvmIr.proto b/compiler/ir/serialization.jvm/src/JvmIr.proto
index 49adcb4d012..0ada03f7d3f 100644
--- a/compiler/ir/serialization.jvm/src/JvmIr.proto
+++ b/compiler/ir/serialization.jvm/src/JvmIr.proto
@@ -16,11 +16,11 @@ message XStatementOrExpression {
 
 message AuxTables {
   // TODO: optimize the representation.
-  repeated bytes type = 1;
-  repeated bytes signature = 2;
-  repeated bytes string = 3;
-  repeated bytes body = 4;
-  repeated bytes debug_info = 5;
+  repeated common.serialization.proto.IrType type = 1;
+  repeated common.serialization.proto.IdSignature signature = 2;
+  repeated string string = 3;
+  repeated XStatementOrExpression body = 4;
+  repeated string debug_info = 5;
 }
 
 message JvmIrFile {
diff --git a/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/JvmIrSerializerSession.kt b/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/JvmIrSerializerSession.kt
index abc47026354..bb45883736c 100644
--- a/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/JvmIrSerializerSession.kt
+++ b/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/JvmIrSerializerSession.kt
@@ -54,11 +54,16 @@ class JvmIrSerializerSession(
 
     private fun serializeAuxTables(): JvmIr.AuxTables {
         val proto = JvmIr.AuxTables.newBuilder()
-        protoTypeArray.forEach { proto.addType(it.toByteString()) }
-        protoIdSignatureArray.forEach { proto.addSignature(it.toByteString()) }
-        protoStringArray.forEach { proto.addString(ByteString.copyFromUtf8(it)) }
-        protoBodyArray.forEach { proto.addBody(ByteString.copyFrom(it.toByteArray())) }
-        protoDebugInfoArray.forEach { proto.addDebugInfo(ByteString.copyFromUtf8(it)) }
+        protoTypeArray.forEach(proto::addType)
+        protoIdSignatureArray.forEach(proto::addSignature)
+        protoStringArray.forEach(proto::addString)
+        protoBodyArray.forEach { proto.addBody(it.toProto()) }
+        protoDebugInfoArray.forEach(proto::addDebugInfo)
         return proto.build()
     }
+
+    fun XStatementOrExpression.toProto(): JvmIr.XStatementOrExpression = when (this) {
+        is XStatementOrExpression.XStatement -> JvmIr.XStatementOrExpression.newBuilder().setStatement(toProtoStatement()).build()
+        is XStatementOrExpression.XExpression -> JvmIr.XStatementOrExpression.newBuilder().setExpression(toProtoExpression()).build()
+    }
 }
\ No newline at end of file
diff --git a/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/deserializeLazyDeclarations.kt b/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/deserializeLazyDeclarations.kt
index bc21d47a0a7..a238140a3f2 100644
--- a/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/deserializeLazyDeclarations.kt
+++ b/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/deserializeLazyDeclarations.kt
@@ -29,7 +29,11 @@ import org.jetbrains.kotlin.ir.types.IrTypeSystemContext
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitorVoid
 import org.jetbrains.kotlin.ir.visitors.acceptChildrenVoid
-import org.jetbrains.kotlin.protobuf.ByteString
+import org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature as ProtoIdSignature
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrDeclaration as ProtoDeclaration
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrExpression as ProtoExpression
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrStatement as ProtoStatement
+import org.jetbrains.kotlin.backend.common.serialization.proto.IrType as ProtoType
 
 fun deserializeClassFromByteArray(
     byteArray: ByteArray,
@@ -40,7 +44,7 @@ fun deserializeClassFromByteArray(
 ) {
     val irBuiltIns = stubGenerator.irBuiltIns
     val symbolTable = stubGenerator.symbolTable
-    val irProto = JvmIr.JvmIrClass.parseFrom(byteArray)
+    val irProto = JvmIr.JvmIrClass.parseFrom(byteArray.codedInputStream)
     val irLibraryFile = IrLibraryFileFromAnnotation(
         irProto.auxTables.typeList,
         irProto.auxTables.signatureList,
@@ -98,7 +102,7 @@ fun deserializeIrFileFromByteArray(
 ) {
     val irBuiltIns = stubGenerator.irBuiltIns
     val symbolTable = stubGenerator.symbolTable
-    val irProto = JvmIr.JvmIrFile.parseFrom(byteArray)
+    val irProto = JvmIr.JvmIrFile.parseFrom(byteArray.codedInputStream)
     val irLibraryFile = IrLibraryFileFromAnnotation(
         irProto.auxTables.typeList,
         irProto.auxTables.signatureList,
@@ -151,21 +155,26 @@ fun deserializeIrFileFromByteArray(
 }
 
 private class IrLibraryFileFromAnnotation(
-    private val types: List<ByteString>,
-    private val signatures: List<ByteString>,
-    private val strings: List<ByteString>,
-    private val bodies: List<ByteString>,
-    private val debugInfo: List<ByteString>
+    private val types: List<ProtoType>,
+    private val signatures: List<ProtoIdSignature>,
+    private val strings: List<String>,
+    private val bodies: List<JvmIr.XStatementOrExpression>,
+    private val debugInfo: List<String>
 ) : IrLibraryFile() {
-    override fun irDeclaration(index: Int): ByteArray {
+    override fun declaration(index: Int): ProtoDeclaration {
         error("This method is never supposed to be called")
     }
 
-    override fun type(index: Int): ByteArray = types[index].toByteArray()
-    override fun signature(index: Int): ByteArray = signatures[index].toByteArray()
-    override fun string(index: Int): ByteArray = strings[index].toByteArray()
-    override fun body(index: Int): ByteArray = bodies[index].toByteArray()
-    override fun debugInfo(index: Int): ByteArray = debugInfo[index].toByteArray()
+    override fun type(index: Int): ProtoType = types[index]
+    override fun signature(index: Int): ProtoIdSignature = signatures[index]
+    override fun string(index: Int): String = strings[index]
+    override fun debugInfo(index: Int): String = debugInfo[index]
+
+    override fun expressionBody(index: Int): ProtoExpression =
+        bodies[index].also { require(it.hasExpression()) }.expression
+
+    override fun statementBody(index: Int): ProtoStatement =
+        bodies[index].also { require(it.hasStatement()) }.statement
 }
 
 private fun referencePublicSymbol(
diff --git a/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/proto/JvmIr.java b/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/proto/JvmIr.java
index 290a6954fb3..d35d74cef56 100644
--- a/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/proto/JvmIr.java
+++ b/compiler/ir/serialization.jvm/src/org/jetbrains/kotlin/backend/jvm/serialization/proto/JvmIr.java
@@ -598,81 +598,96 @@ public final class JvmIr {
       org.jetbrains.kotlin.protobuf.MessageLiteOrBuilder {
 
     /**
-     * <code>repeated bytes type = 1;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
      *
      * <pre>
      * TODO: optimize the representation.
      * </pre>
      */
-    java.util.List<org.jetbrains.kotlin.protobuf.ByteString> getTypeList();
+    java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IrType> 
+        getTypeList();
     /**
-     * <code>repeated bytes type = 1;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+     *
+     * <pre>
+     * TODO: optimize the representation.
+     * </pre>
+     */
+    org.jetbrains.kotlin.backend.common.serialization.proto.IrType getType(int index);
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
      *
      * <pre>
      * TODO: optimize the representation.
      * </pre>
      */
     int getTypeCount();
-    /**
-     * <code>repeated bytes type = 1;</code>
-     *
-     * <pre>
-     * TODO: optimize the representation.
-     * </pre>
-     */
-    org.jetbrains.kotlin.protobuf.ByteString getType(int index);
 
     /**
-     * <code>repeated bytes signature = 2;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
      */
-    java.util.List<org.jetbrains.kotlin.protobuf.ByteString> getSignatureList();
+    java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature> 
+        getSignatureList();
     /**
-     * <code>repeated bytes signature = 2;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+     */
+    org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature getSignature(int index);
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
      */
     int getSignatureCount();
-    /**
-     * <code>repeated bytes signature = 2;</code>
-     */
-    org.jetbrains.kotlin.protobuf.ByteString getSignature(int index);
 
     /**
-     * <code>repeated bytes string = 3;</code>
+     * <code>repeated string string = 3;</code>
      */
-    java.util.List<org.jetbrains.kotlin.protobuf.ByteString> getStringList();
+    org.jetbrains.kotlin.protobuf.ProtocolStringList
+        getStringList();
     /**
-     * <code>repeated bytes string = 3;</code>
+     * <code>repeated string string = 3;</code>
      */
     int getStringCount();
     /**
-     * <code>repeated bytes string = 3;</code>
+     * <code>repeated string string = 3;</code>
      */
-    org.jetbrains.kotlin.protobuf.ByteString getString(int index);
+    java.lang.String getString(int index);
+    /**
+     * <code>repeated string string = 3;</code>
+     */
+    org.jetbrains.kotlin.protobuf.ByteString
+        getStringBytes(int index);
 
     /**
-     * <code>repeated bytes body = 4;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
      */
-    java.util.List<org.jetbrains.kotlin.protobuf.ByteString> getBodyList();
+    java.util.List<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression> 
+        getBodyList();
     /**
-     * <code>repeated bytes body = 4;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+     */
+    org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression getBody(int index);
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
      */
     int getBodyCount();
-    /**
-     * <code>repeated bytes body = 4;</code>
-     */
-    org.jetbrains.kotlin.protobuf.ByteString getBody(int index);
 
     /**
-     * <code>repeated bytes debug_info = 5;</code>
+     * <code>repeated string debug_info = 5;</code>
      */
-    java.util.List<org.jetbrains.kotlin.protobuf.ByteString> getDebugInfoList();
+    org.jetbrains.kotlin.protobuf.ProtocolStringList
+        getDebugInfoList();
     /**
-     * <code>repeated bytes debug_info = 5;</code>
+     * <code>repeated string debug_info = 5;</code>
      */
     int getDebugInfoCount();
     /**
-     * <code>repeated bytes debug_info = 5;</code>
+     * <code>repeated string debug_info = 5;</code>
      */
-    org.jetbrains.kotlin.protobuf.ByteString getDebugInfo(int index);
+    java.lang.String getDebugInfo(int index);
+    /**
+     * <code>repeated string debug_info = 5;</code>
+     */
+    org.jetbrains.kotlin.protobuf.ByteString
+        getDebugInfoBytes(int index);
   }
   /**
    * Protobuf type {@code org.jetbrains.kotlin.backend.jvm.serialization.proto.AuxTables}
@@ -726,42 +741,44 @@ public final class JvmIr {
             }
             case 10: {
               if (!((mutable_bitField0_ & 0x00000001) == 0x00000001)) {
-                type_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>();
+                type_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.common.serialization.proto.IrType>();
                 mutable_bitField0_ |= 0x00000001;
               }
-              type_.add(input.readBytes());
+              type_.add(input.readMessage(org.jetbrains.kotlin.backend.common.serialization.proto.IrType.PARSER, extensionRegistry));
               break;
             }
             case 18: {
               if (!((mutable_bitField0_ & 0x00000002) == 0x00000002)) {
-                signature_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>();
+                signature_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature>();
                 mutable_bitField0_ |= 0x00000002;
               }
-              signature_.add(input.readBytes());
+              signature_.add(input.readMessage(org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature.PARSER, extensionRegistry));
               break;
             }
             case 26: {
+              org.jetbrains.kotlin.protobuf.ByteString bs = input.readBytes();
               if (!((mutable_bitField0_ & 0x00000004) == 0x00000004)) {
-                string_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>();
+                string_ = new org.jetbrains.kotlin.protobuf.LazyStringArrayList();
                 mutable_bitField0_ |= 0x00000004;
               }
-              string_.add(input.readBytes());
+              string_.add(bs);
               break;
             }
             case 34: {
               if (!((mutable_bitField0_ & 0x00000008) == 0x00000008)) {
-                body_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>();
+                body_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression>();
                 mutable_bitField0_ |= 0x00000008;
               }
-              body_.add(input.readBytes());
+              body_.add(input.readMessage(org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression.PARSER, extensionRegistry));
               break;
             }
             case 42: {
+              org.jetbrains.kotlin.protobuf.ByteString bs = input.readBytes();
               if (!((mutable_bitField0_ & 0x00000010) == 0x00000010)) {
-                debugInfo_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>();
+                debugInfo_ = new org.jetbrains.kotlin.protobuf.LazyStringArrayList();
                 mutable_bitField0_ |= 0x00000010;
               }
-              debugInfo_.add(input.readBytes());
+              debugInfo_.add(bs);
               break;
             }
           }
@@ -779,13 +796,13 @@ public final class JvmIr {
           signature_ = java.util.Collections.unmodifiableList(signature_);
         }
         if (((mutable_bitField0_ & 0x00000004) == 0x00000004)) {
-          string_ = java.util.Collections.unmodifiableList(string_);
+          string_ = string_.getUnmodifiableView();
         }
         if (((mutable_bitField0_ & 0x00000008) == 0x00000008)) {
           body_ = java.util.Collections.unmodifiableList(body_);
         }
         if (((mutable_bitField0_ & 0x00000010) == 0x00000010)) {
-          debugInfo_ = java.util.Collections.unmodifiableList(debugInfo_);
+          debugInfo_ = debugInfo_.getUnmodifiableView();
         }
         try {
           unknownFieldsCodedOutput.flush();
@@ -813,20 +830,30 @@ public final class JvmIr {
     }
 
     public static final int TYPE_FIELD_NUMBER = 1;
-    private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> type_;
+    private java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IrType> type_;
     /**
-     * <code>repeated bytes type = 1;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
      *
      * <pre>
      * TODO: optimize the representation.
      * </pre>
      */
-    public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
-        getTypeList() {
+    public java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IrType> getTypeList() {
       return type_;
     }
     /**
-     * <code>repeated bytes type = 1;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+     *
+     * <pre>
+     * TODO: optimize the representation.
+     * </pre>
+     */
+    public java.util.List<? extends org.jetbrains.kotlin.backend.common.serialization.proto.IrTypeOrBuilder> 
+        getTypeOrBuilderList() {
+      return type_;
+    }
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
      *
      * <pre>
      * TODO: optimize the representation.
@@ -836,110 +863,161 @@ public final class JvmIr {
       return type_.size();
     }
     /**
-     * <code>repeated bytes type = 1;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
      *
      * <pre>
      * TODO: optimize the representation.
      * </pre>
      */
-    public org.jetbrains.kotlin.protobuf.ByteString getType(int index) {
+    public org.jetbrains.kotlin.backend.common.serialization.proto.IrType getType(int index) {
+      return type_.get(index);
+    }
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+     *
+     * <pre>
+     * TODO: optimize the representation.
+     * </pre>
+     */
+    public org.jetbrains.kotlin.backend.common.serialization.proto.IrTypeOrBuilder getTypeOrBuilder(
+        int index) {
       return type_.get(index);
     }
 
     public static final int SIGNATURE_FIELD_NUMBER = 2;
-    private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> signature_;
+    private java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature> signature_;
     /**
-     * <code>repeated bytes signature = 2;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
      */
-    public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
-        getSignatureList() {
+    public java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature> getSignatureList() {
       return signature_;
     }
     /**
-     * <code>repeated bytes signature = 2;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+     */
+    public java.util.List<? extends org.jetbrains.kotlin.backend.common.serialization.proto.IdSignatureOrBuilder> 
+        getSignatureOrBuilderList() {
+      return signature_;
+    }
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
      */
     public int getSignatureCount() {
       return signature_.size();
     }
     /**
-     * <code>repeated bytes signature = 2;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
      */
-    public org.jetbrains.kotlin.protobuf.ByteString getSignature(int index) {
+    public org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature getSignature(int index) {
+      return signature_.get(index);
+    }
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+     */
+    public org.jetbrains.kotlin.backend.common.serialization.proto.IdSignatureOrBuilder getSignatureOrBuilder(
+        int index) {
       return signature_.get(index);
     }
 
     public static final int STRING_FIELD_NUMBER = 3;
-    private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> string_;
+    private org.jetbrains.kotlin.protobuf.LazyStringList string_;
     /**
-     * <code>repeated bytes string = 3;</code>
+     * <code>repeated string string = 3;</code>
      */
-    public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
+    public org.jetbrains.kotlin.protobuf.ProtocolStringList
         getStringList() {
       return string_;
     }
     /**
-     * <code>repeated bytes string = 3;</code>
+     * <code>repeated string string = 3;</code>
      */
     public int getStringCount() {
       return string_.size();
     }
     /**
-     * <code>repeated bytes string = 3;</code>
+     * <code>repeated string string = 3;</code>
      */
-    public org.jetbrains.kotlin.protobuf.ByteString getString(int index) {
+    public java.lang.String getString(int index) {
       return string_.get(index);
     }
+    /**
+     * <code>repeated string string = 3;</code>
+     */
+    public org.jetbrains.kotlin.protobuf.ByteString
+        getStringBytes(int index) {
+      return string_.getByteString(index);
+    }
 
     public static final int BODY_FIELD_NUMBER = 4;
-    private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> body_;
+    private java.util.List<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression> body_;
     /**
-     * <code>repeated bytes body = 4;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
      */
-    public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
-        getBodyList() {
+    public java.util.List<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression> getBodyList() {
       return body_;
     }
     /**
-     * <code>repeated bytes body = 4;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+     */
+    public java.util.List<? extends org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpressionOrBuilder> 
+        getBodyOrBuilderList() {
+      return body_;
+    }
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
      */
     public int getBodyCount() {
       return body_.size();
     }
     /**
-     * <code>repeated bytes body = 4;</code>
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
      */
-    public org.jetbrains.kotlin.protobuf.ByteString getBody(int index) {
+    public org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression getBody(int index) {
+      return body_.get(index);
+    }
+    /**
+     * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+     */
+    public org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpressionOrBuilder getBodyOrBuilder(
+        int index) {
       return body_.get(index);
     }
 
     public static final int DEBUG_INFO_FIELD_NUMBER = 5;
-    private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> debugInfo_;
+    private org.jetbrains.kotlin.protobuf.LazyStringList debugInfo_;
     /**
-     * <code>repeated bytes debug_info = 5;</code>
+     * <code>repeated string debug_info = 5;</code>
      */
-    public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
+    public org.jetbrains.kotlin.protobuf.ProtocolStringList
         getDebugInfoList() {
       return debugInfo_;
     }
     /**
-     * <code>repeated bytes debug_info = 5;</code>
+     * <code>repeated string debug_info = 5;</code>
      */
     public int getDebugInfoCount() {
       return debugInfo_.size();
     }
     /**
-     * <code>repeated bytes debug_info = 5;</code>
+     * <code>repeated string debug_info = 5;</code>
      */
-    public org.jetbrains.kotlin.protobuf.ByteString getDebugInfo(int index) {
+    public java.lang.String getDebugInfo(int index) {
       return debugInfo_.get(index);
     }
+    /**
+     * <code>repeated string debug_info = 5;</code>
+     */
+    public org.jetbrains.kotlin.protobuf.ByteString
+        getDebugInfoBytes(int index) {
+      return debugInfo_.getByteString(index);
+    }
 
     private void initFields() {
       type_ = java.util.Collections.emptyList();
       signature_ = java.util.Collections.emptyList();
-      string_ = java.util.Collections.emptyList();
+      string_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
       body_ = java.util.Collections.emptyList();
-      debugInfo_ = java.util.Collections.emptyList();
+      debugInfo_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
     }
     private byte memoizedIsInitialized = -1;
     public final boolean isInitialized() {
@@ -947,6 +1025,24 @@ public final class JvmIr {
       if (isInitialized == 1) return true;
       if (isInitialized == 0) return false;
 
+      for (int i = 0; i < getTypeCount(); i++) {
+        if (!getType(i).isInitialized()) {
+          memoizedIsInitialized = 0;
+          return false;
+        }
+      }
+      for (int i = 0; i < getSignatureCount(); i++) {
+        if (!getSignature(i).isInitialized()) {
+          memoizedIsInitialized = 0;
+          return false;
+        }
+      }
+      for (int i = 0; i < getBodyCount(); i++) {
+        if (!getBody(i).isInitialized()) {
+          memoizedIsInitialized = 0;
+          return false;
+        }
+      }
       memoizedIsInitialized = 1;
       return true;
     }
@@ -955,19 +1051,19 @@ public final class JvmIr {
                         throws java.io.IOException {
       getSerializedSize();
       for (int i = 0; i < type_.size(); i++) {
-        output.writeBytes(1, type_.get(i));
+        output.writeMessage(1, type_.get(i));
       }
       for (int i = 0; i < signature_.size(); i++) {
-        output.writeBytes(2, signature_.get(i));
+        output.writeMessage(2, signature_.get(i));
       }
       for (int i = 0; i < string_.size(); i++) {
-        output.writeBytes(3, string_.get(i));
+        output.writeBytes(3, string_.getByteString(i));
       }
       for (int i = 0; i < body_.size(); i++) {
-        output.writeBytes(4, body_.get(i));
+        output.writeMessage(4, body_.get(i));
       }
       for (int i = 0; i < debugInfo_.size(); i++) {
-        output.writeBytes(5, debugInfo_.get(i));
+        output.writeBytes(5, debugInfo_.getByteString(i));
       }
       output.writeRawBytes(unknownFields);
     }
@@ -978,47 +1074,32 @@ public final class JvmIr {
       if (size != -1) return size;
 
       size = 0;
-      {
-        int dataSize = 0;
-        for (int i = 0; i < type_.size(); i++) {
-          dataSize += org.jetbrains.kotlin.protobuf.CodedOutputStream
-            .computeBytesSizeNoTag(type_.get(i));
-        }
-        size += dataSize;
-        size += 1 * getTypeList().size();
+      for (int i = 0; i < type_.size(); i++) {
+        size += org.jetbrains.kotlin.protobuf.CodedOutputStream
+          .computeMessageSize(1, type_.get(i));
       }
-      {
-        int dataSize = 0;
-        for (int i = 0; i < signature_.size(); i++) {
-          dataSize += org.jetbrains.kotlin.protobuf.CodedOutputStream
-            .computeBytesSizeNoTag(signature_.get(i));
-        }
-        size += dataSize;
-        size += 1 * getSignatureList().size();
+      for (int i = 0; i < signature_.size(); i++) {
+        size += org.jetbrains.kotlin.protobuf.CodedOutputStream
+          .computeMessageSize(2, signature_.get(i));
       }
       {
         int dataSize = 0;
         for (int i = 0; i < string_.size(); i++) {
           dataSize += org.jetbrains.kotlin.protobuf.CodedOutputStream
-            .computeBytesSizeNoTag(string_.get(i));
+            .computeBytesSizeNoTag(string_.getByteString(i));
         }
         size += dataSize;
         size += 1 * getStringList().size();
       }
-      {
-        int dataSize = 0;
-        for (int i = 0; i < body_.size(); i++) {
-          dataSize += org.jetbrains.kotlin.protobuf.CodedOutputStream
-            .computeBytesSizeNoTag(body_.get(i));
-        }
-        size += dataSize;
-        size += 1 * getBodyList().size();
+      for (int i = 0; i < body_.size(); i++) {
+        size += org.jetbrains.kotlin.protobuf.CodedOutputStream
+          .computeMessageSize(4, body_.get(i));
       }
       {
         int dataSize = 0;
         for (int i = 0; i < debugInfo_.size(); i++) {
           dataSize += org.jetbrains.kotlin.protobuf.CodedOutputStream
-            .computeBytesSizeNoTag(debugInfo_.get(i));
+            .computeBytesSizeNoTag(debugInfo_.getByteString(i));
         }
         size += dataSize;
         size += 1 * getDebugInfoList().size();
@@ -1121,11 +1202,11 @@ public final class JvmIr {
         bitField0_ = (bitField0_ & ~0x00000001);
         signature_ = java.util.Collections.emptyList();
         bitField0_ = (bitField0_ & ~0x00000002);
-        string_ = java.util.Collections.emptyList();
+        string_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
         bitField0_ = (bitField0_ & ~0x00000004);
         body_ = java.util.Collections.emptyList();
         bitField0_ = (bitField0_ & ~0x00000008);
-        debugInfo_ = java.util.Collections.emptyList();
+        debugInfo_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
         bitField0_ = (bitField0_ & ~0x00000010);
         return this;
       }
@@ -1160,7 +1241,7 @@ public final class JvmIr {
         }
         result.signature_ = signature_;
         if (((bitField0_ & 0x00000004) == 0x00000004)) {
-          string_ = java.util.Collections.unmodifiableList(string_);
+          string_ = string_.getUnmodifiableView();
           bitField0_ = (bitField0_ & ~0x00000004);
         }
         result.string_ = string_;
@@ -1170,7 +1251,7 @@ public final class JvmIr {
         }
         result.body_ = body_;
         if (((bitField0_ & 0x00000010) == 0x00000010)) {
-          debugInfo_ = java.util.Collections.unmodifiableList(debugInfo_);
+          debugInfo_ = debugInfo_.getUnmodifiableView();
           bitField0_ = (bitField0_ & ~0x00000010);
         }
         result.debugInfo_ = debugInfo_;
@@ -1235,6 +1316,24 @@ public final class JvmIr {
       }
 
       public final boolean isInitialized() {
+        for (int i = 0; i < getTypeCount(); i++) {
+          if (!getType(i).isInitialized()) {
+            
+            return false;
+          }
+        }
+        for (int i = 0; i < getSignatureCount(); i++) {
+          if (!getSignature(i).isInitialized()) {
+            
+            return false;
+          }
+        }
+        for (int i = 0; i < getBodyCount(); i++) {
+          if (!getBody(i).isInitialized()) {
+            
+            return false;
+          }
+        }
         return true;
       }
 
@@ -1257,26 +1356,27 @@ public final class JvmIr {
       }
       private int bitField0_;
 
-      private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> type_ = java.util.Collections.emptyList();
+      private java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IrType> type_ =
+        java.util.Collections.emptyList();
       private void ensureTypeIsMutable() {
         if (!((bitField0_ & 0x00000001) == 0x00000001)) {
-          type_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>(type_);
+          type_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.common.serialization.proto.IrType>(type_);
           bitField0_ |= 0x00000001;
          }
       }
+
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
        * </pre>
        */
-      public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
-          getTypeList() {
+      public java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IrType> getTypeList() {
         return java.util.Collections.unmodifiableList(type_);
       }
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
@@ -1286,65 +1386,124 @@ public final class JvmIr {
         return type_.size();
       }
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
        * </pre>
        */
-      public org.jetbrains.kotlin.protobuf.ByteString getType(int index) {
+      public org.jetbrains.kotlin.backend.common.serialization.proto.IrType getType(int index) {
         return type_.get(index);
       }
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
        * </pre>
        */
       public Builder setType(
-          int index, org.jetbrains.kotlin.protobuf.ByteString value) {
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IrType value) {
         if (value == null) {
-    throw new NullPointerException();
-  }
-  ensureTypeIsMutable();
+          throw new NullPointerException();
+        }
+        ensureTypeIsMutable();
         type_.set(index, value);
-        
+
         return this;
       }
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
        * </pre>
        */
-      public Builder addType(org.jetbrains.kotlin.protobuf.ByteString value) {
-        if (value == null) {
-    throw new NullPointerException();
-  }
-  ensureTypeIsMutable();
-        type_.add(value);
-        
+      public Builder setType(
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IrType.Builder builderForValue) {
+        ensureTypeIsMutable();
+        type_.set(index, builderForValue.build());
+
         return this;
       }
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+       *
+       * <pre>
+       * TODO: optimize the representation.
+       * </pre>
+       */
+      public Builder addType(org.jetbrains.kotlin.backend.common.serialization.proto.IrType value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        ensureTypeIsMutable();
+        type_.add(value);
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+       *
+       * <pre>
+       * TODO: optimize the representation.
+       * </pre>
+       */
+      public Builder addType(
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IrType value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        ensureTypeIsMutable();
+        type_.add(index, value);
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+       *
+       * <pre>
+       * TODO: optimize the representation.
+       * </pre>
+       */
+      public Builder addType(
+          org.jetbrains.kotlin.backend.common.serialization.proto.IrType.Builder builderForValue) {
+        ensureTypeIsMutable();
+        type_.add(builderForValue.build());
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+       *
+       * <pre>
+       * TODO: optimize the representation.
+       * </pre>
+       */
+      public Builder addType(
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IrType.Builder builderForValue) {
+        ensureTypeIsMutable();
+        type_.add(index, builderForValue.build());
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
        * </pre>
        */
       public Builder addAllType(
-          java.lang.Iterable<? extends org.jetbrains.kotlin.protobuf.ByteString> values) {
+          java.lang.Iterable<? extends org.jetbrains.kotlin.backend.common.serialization.proto.IrType> values) {
         ensureTypeIsMutable();
         org.jetbrains.kotlin.protobuf.AbstractMessageLite.Builder.addAll(
             values, type_);
-        
+
         return this;
       }
       /**
-       * <code>repeated bytes type = 1;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
        *
        * <pre>
        * TODO: optimize the representation.
@@ -1353,113 +1512,186 @@ public final class JvmIr {
       public Builder clearType() {
         type_ = java.util.Collections.emptyList();
         bitField0_ = (bitField0_ & ~0x00000001);
-        
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IrType type = 1;</code>
+       *
+       * <pre>
+       * TODO: optimize the representation.
+       * </pre>
+       */
+      public Builder removeType(int index) {
+        ensureTypeIsMutable();
+        type_.remove(index);
+
         return this;
       }
 
-      private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> signature_ = java.util.Collections.emptyList();
+      private java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature> signature_ =
+        java.util.Collections.emptyList();
       private void ensureSignatureIsMutable() {
         if (!((bitField0_ & 0x00000002) == 0x00000002)) {
-          signature_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>(signature_);
+          signature_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature>(signature_);
           bitField0_ |= 0x00000002;
          }
       }
+
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
-      public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
-          getSignatureList() {
+      public java.util.List<org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature> getSignatureList() {
         return java.util.Collections.unmodifiableList(signature_);
       }
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
       public int getSignatureCount() {
         return signature_.size();
       }
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
-      public org.jetbrains.kotlin.protobuf.ByteString getSignature(int index) {
+      public org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature getSignature(int index) {
         return signature_.get(index);
       }
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
       public Builder setSignature(
-          int index, org.jetbrains.kotlin.protobuf.ByteString value) {
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature value) {
         if (value == null) {
-    throw new NullPointerException();
-  }
-  ensureSignatureIsMutable();
+          throw new NullPointerException();
+        }
+        ensureSignatureIsMutable();
         signature_.set(index, value);
-        
+
         return this;
       }
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
-      public Builder addSignature(org.jetbrains.kotlin.protobuf.ByteString value) {
-        if (value == null) {
-    throw new NullPointerException();
-  }
-  ensureSignatureIsMutable();
-        signature_.add(value);
-        
+      public Builder setSignature(
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature.Builder builderForValue) {
+        ensureSignatureIsMutable();
+        signature_.set(index, builderForValue.build());
+
         return this;
       }
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+       */
+      public Builder addSignature(org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        ensureSignatureIsMutable();
+        signature_.add(value);
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+       */
+      public Builder addSignature(
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        ensureSignatureIsMutable();
+        signature_.add(index, value);
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+       */
+      public Builder addSignature(
+          org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature.Builder builderForValue) {
+        ensureSignatureIsMutable();
+        signature_.add(builderForValue.build());
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+       */
+      public Builder addSignature(
+          int index, org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature.Builder builderForValue) {
+        ensureSignatureIsMutable();
+        signature_.add(index, builderForValue.build());
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
       public Builder addAllSignature(
-          java.lang.Iterable<? extends org.jetbrains.kotlin.protobuf.ByteString> values) {
+          java.lang.Iterable<? extends org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature> values) {
         ensureSignatureIsMutable();
         org.jetbrains.kotlin.protobuf.AbstractMessageLite.Builder.addAll(
             values, signature_);
-        
+
         return this;
       }
       /**
-       * <code>repeated bytes signature = 2;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
        */
       public Builder clearSignature() {
         signature_ = java.util.Collections.emptyList();
         bitField0_ = (bitField0_ & ~0x00000002);
-        
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.common.serialization.proto.IdSignature signature = 2;</code>
+       */
+      public Builder removeSignature(int index) {
+        ensureSignatureIsMutable();
+        signature_.remove(index);
+
         return this;
       }
 
-      private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> string_ = java.util.Collections.emptyList();
+      private org.jetbrains.kotlin.protobuf.LazyStringList string_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
       private void ensureStringIsMutable() {
         if (!((bitField0_ & 0x00000004) == 0x00000004)) {
-          string_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>(string_);
+          string_ = new org.jetbrains.kotlin.protobuf.LazyStringArrayList(string_);
           bitField0_ |= 0x00000004;
          }
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
        */
-      public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
+      public org.jetbrains.kotlin.protobuf.ProtocolStringList
           getStringList() {
-        return java.util.Collections.unmodifiableList(string_);
+        return string_.getUnmodifiableView();
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
        */
       public int getStringCount() {
         return string_.size();
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
        */
-      public org.jetbrains.kotlin.protobuf.ByteString getString(int index) {
+      public java.lang.String getString(int index) {
         return string_.get(index);
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
+       */
+      public org.jetbrains.kotlin.protobuf.ByteString
+          getStringBytes(int index) {
+        return string_.getByteString(index);
+      }
+      /**
+       * <code>repeated string string = 3;</code>
        */
       public Builder setString(
-          int index, org.jetbrains.kotlin.protobuf.ByteString value) {
+          int index, java.lang.String value) {
         if (value == null) {
     throw new NullPointerException();
   }
@@ -1469,9 +1701,10 @@ public final class JvmIr {
         return this;
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
        */
-      public Builder addString(org.jetbrains.kotlin.protobuf.ByteString value) {
+      public Builder addString(
+          java.lang.String value) {
         if (value == null) {
     throw new NullPointerException();
   }
@@ -1481,10 +1714,10 @@ public final class JvmIr {
         return this;
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
        */
       public Builder addAllString(
-          java.lang.Iterable<? extends org.jetbrains.kotlin.protobuf.ByteString> values) {
+          java.lang.Iterable<java.lang.String> values) {
         ensureStringIsMutable();
         org.jetbrains.kotlin.protobuf.AbstractMessageLite.Builder.addAll(
             values, string_);
@@ -1492,118 +1725,191 @@ public final class JvmIr {
         return this;
       }
       /**
-       * <code>repeated bytes string = 3;</code>
+       * <code>repeated string string = 3;</code>
        */
       public Builder clearString() {
-        string_ = java.util.Collections.emptyList();
+        string_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
         bitField0_ = (bitField0_ & ~0x00000004);
         
         return this;
       }
+      /**
+       * <code>repeated string string = 3;</code>
+       */
+      public Builder addStringBytes(
+          org.jetbrains.kotlin.protobuf.ByteString value) {
+        if (value == null) {
+    throw new NullPointerException();
+  }
+  ensureStringIsMutable();
+        string_.add(value);
+        
+        return this;
+      }
 
-      private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> body_ = java.util.Collections.emptyList();
+      private java.util.List<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression> body_ =
+        java.util.Collections.emptyList();
       private void ensureBodyIsMutable() {
         if (!((bitField0_ & 0x00000008) == 0x00000008)) {
-          body_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>(body_);
+          body_ = new java.util.ArrayList<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression>(body_);
           bitField0_ |= 0x00000008;
          }
       }
+
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
-      public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
-          getBodyList() {
+      public java.util.List<org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression> getBodyList() {
         return java.util.Collections.unmodifiableList(body_);
       }
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
       public int getBodyCount() {
         return body_.size();
       }
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
-      public org.jetbrains.kotlin.protobuf.ByteString getBody(int index) {
+      public org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression getBody(int index) {
         return body_.get(index);
       }
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
       public Builder setBody(
-          int index, org.jetbrains.kotlin.protobuf.ByteString value) {
+          int index, org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression value) {
         if (value == null) {
-    throw new NullPointerException();
-  }
-  ensureBodyIsMutable();
+          throw new NullPointerException();
+        }
+        ensureBodyIsMutable();
         body_.set(index, value);
-        
+
         return this;
       }
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
-      public Builder addBody(org.jetbrains.kotlin.protobuf.ByteString value) {
-        if (value == null) {
-    throw new NullPointerException();
-  }
-  ensureBodyIsMutable();
-        body_.add(value);
-        
+      public Builder setBody(
+          int index, org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression.Builder builderForValue) {
+        ensureBodyIsMutable();
+        body_.set(index, builderForValue.build());
+
         return this;
       }
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+       */
+      public Builder addBody(org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        ensureBodyIsMutable();
+        body_.add(value);
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+       */
+      public Builder addBody(
+          int index, org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression value) {
+        if (value == null) {
+          throw new NullPointerException();
+        }
+        ensureBodyIsMutable();
+        body_.add(index, value);
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+       */
+      public Builder addBody(
+          org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression.Builder builderForValue) {
+        ensureBodyIsMutable();
+        body_.add(builderForValue.build());
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+       */
+      public Builder addBody(
+          int index, org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression.Builder builderForValue) {
+        ensureBodyIsMutable();
+        body_.add(index, builderForValue.build());
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
       public Builder addAllBody(
-          java.lang.Iterable<? extends org.jetbrains.kotlin.protobuf.ByteString> values) {
+          java.lang.Iterable<? extends org.jetbrains.kotlin.backend.jvm.serialization.proto.JvmIr.XStatementOrExpression> values) {
         ensureBodyIsMutable();
         org.jetbrains.kotlin.protobuf.AbstractMessageLite.Builder.addAll(
             values, body_);
-        
+
         return this;
       }
       /**
-       * <code>repeated bytes body = 4;</code>
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
        */
       public Builder clearBody() {
         body_ = java.util.Collections.emptyList();
         bitField0_ = (bitField0_ & ~0x00000008);
-        
+
+        return this;
+      }
+      /**
+       * <code>repeated .org.jetbrains.kotlin.backend.jvm.serialization.proto.XStatementOrExpression body = 4;</code>
+       */
+      public Builder removeBody(int index) {
+        ensureBodyIsMutable();
+        body_.remove(index);
+
         return this;
       }
 
-      private java.util.List<org.jetbrains.kotlin.protobuf.ByteString> debugInfo_ = java.util.Collections.emptyList();
+      private org.jetbrains.kotlin.protobuf.LazyStringList debugInfo_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
       private void ensureDebugInfoIsMutable() {
         if (!((bitField0_ & 0x00000010) == 0x00000010)) {
-          debugInfo_ = new java.util.ArrayList<org.jetbrains.kotlin.protobuf.ByteString>(debugInfo_);
+          debugInfo_ = new org.jetbrains.kotlin.protobuf.LazyStringArrayList(debugInfo_);
           bitField0_ |= 0x00000010;
          }
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
        */
-      public java.util.List<org.jetbrains.kotlin.protobuf.ByteString>
+      public org.jetbrains.kotlin.protobuf.ProtocolStringList
           getDebugInfoList() {
-        return java.util.Collections.unmodifiableList(debugInfo_);
+        return debugInfo_.getUnmodifiableView();
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
        */
       public int getDebugInfoCount() {
         return debugInfo_.size();
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
        */
-      public org.jetbrains.kotlin.protobuf.ByteString getDebugInfo(int index) {
+      public java.lang.String getDebugInfo(int index) {
         return debugInfo_.get(index);
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
+       */
+      public org.jetbrains.kotlin.protobuf.ByteString
+          getDebugInfoBytes(int index) {
+        return debugInfo_.getByteString(index);
+      }
+      /**
+       * <code>repeated string debug_info = 5;</code>
        */
       public Builder setDebugInfo(
-          int index, org.jetbrains.kotlin.protobuf.ByteString value) {
+          int index, java.lang.String value) {
         if (value == null) {
     throw new NullPointerException();
   }
@@ -1613,9 +1919,10 @@ public final class JvmIr {
         return this;
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
        */
-      public Builder addDebugInfo(org.jetbrains.kotlin.protobuf.ByteString value) {
+      public Builder addDebugInfo(
+          java.lang.String value) {
         if (value == null) {
     throw new NullPointerException();
   }
@@ -1625,10 +1932,10 @@ public final class JvmIr {
         return this;
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
        */
       public Builder addAllDebugInfo(
-          java.lang.Iterable<? extends org.jetbrains.kotlin.protobuf.ByteString> values) {
+          java.lang.Iterable<java.lang.String> values) {
         ensureDebugInfoIsMutable();
         org.jetbrains.kotlin.protobuf.AbstractMessageLite.Builder.addAll(
             values, debugInfo_);
@@ -1636,14 +1943,27 @@ public final class JvmIr {
         return this;
       }
       /**
-       * <code>repeated bytes debug_info = 5;</code>
+       * <code>repeated string debug_info = 5;</code>
        */
       public Builder clearDebugInfo() {
-        debugInfo_ = java.util.Collections.emptyList();
+        debugInfo_ = org.jetbrains.kotlin.protobuf.LazyStringArrayList.EMPTY;
         bitField0_ = (bitField0_ & ~0x00000010);
         
         return this;
       }
+      /**
+       * <code>repeated string debug_info = 5;</code>
+       */
+      public Builder addDebugInfoBytes(
+          org.jetbrains.kotlin.protobuf.ByteString value) {
+        if (value == null) {
+    throw new NullPointerException();
+  }
+  ensureDebugInfoIsMutable();
+        debugInfo_.add(value);
+        
+        return this;
+      }
 
       // @@protoc_insertion_point(builder_scope:org.jetbrains.kotlin.backend.jvm.serialization.proto.AuxTables)
     }
@@ -1988,6 +2308,10 @@ public final class JvmIr {
           return false;
         }
       }
+      if (!getAuxTables().isInitialized()) {
+        memoizedIsInitialized = 0;
+        return false;
+      }
       memoizedIsInitialized = 1;
       return true;
     }
@@ -2242,6 +2566,10 @@ public final class JvmIr {
             return false;
           }
         }
+        if (!getAuxTables().isInitialized()) {
+          
+          return false;
+        }
         return true;
       }
 
@@ -2835,6 +3163,10 @@ public final class JvmIr {
         memoizedIsInitialized = 0;
         return false;
       }
+      if (!getAuxTables().isInitialized()) {
+        memoizedIsInitialized = 0;
+        return false;
+      }
       memoizedIsInitialized = 1;
       return true;
     }
@@ -3024,6 +3356,10 @@ public final class JvmIr {
           
           return false;
         }
+        if (!getAuxTables().isInitialized()) {
+          
+          return false;
+        }
         return true;
       }