Merge pull request swiftlang#29742 from CodaFi/leaving-the-nest

Always write out nested types tables

Author: CodaFi

include/swift/Frontend/FrontendOptions.h

@@ -177,11 +177,6 @@ class FrontendOptions {
   /// entity.
   bool ProfileEntities = false;
 
-  /// If true, serialization encodes an extra lookup table for use in module-
-  /// merging when emitting partial modules (the per-file modules in a non-WMO
-  /// build).
-  bool EnableSerializationNestedTypeLookupTable = true;
-
   /// Indicates whether or not an import statement can pick up a Swift source
   /// file (as opposed to a module file).
   bool EnableSourceImport = false;

include/swift/Option/FrontendOptions.td

@@ -182,10 +182,6 @@ def autolink_library : Separate<["-"], "autolink-library">,
 def disable_typo_correction : Flag<["-"], "disable-typo-correction">,
   HelpText<"Disable typo correction">;
 
-def disable_serialization_nested_type_lookup_table :
-  Flag<["-"], "disable-serialization-nested-type-lookup-table">,
-  HelpText<"Force module merging to use regular lookups to find nested types">;
-
 } // end let Flags = [FrontendOption, NoDriverOption]
 
 def debug_crash_Group : OptionGroup<"<automatic crashing options>">;

include/swift/Serialization/SerializationOptions.h

@@ -128,7 +128,6 @@ namespace swift {
     ArrayRef<FileDependency> Dependencies;
 
     bool AutolinkForceLoad = false;
-    bool EnableNestedTypeLookupTable = false;
     bool SerializeAllSIL = false;
     bool SerializeOptionsForDebugging = false;
     bool IsSIB = false;

lib/Frontend/ArgsToFrontendOptionsConverter.cpp

@@ -174,8 +174,6 @@ bool ArgsToFrontendOptionsConverter::convert(
 
   Opts.EnableSourceImport |= Args.hasArg(OPT_enable_source_import);
   Opts.ImportUnderlyingModule |= Args.hasArg(OPT_import_underlying_module);
-  Opts.EnableSerializationNestedTypeLookupTable &=
-      !Args.hasArg(OPT_disable_serialization_nested_type_lookup_table);
 
   computeImportObjCHeaderOptions();
   computeImplicitImportModuleNames();

lib/Frontend/Frontend.cpp

@@ -154,8 +154,6 @@ SerializationOptions CompilerInvocation::computeSerializationOptions(
     serializationOpts.ImportedHeader = opts.ImplicitObjCHeaderPath;
   serializationOpts.ModuleLinkName = opts.ModuleLinkName;
   serializationOpts.ExtraClangOptions = getClangImporterOptions().ExtraArgs;
-  serializationOpts.EnableNestedTypeLookupTable =
-      opts.EnableSerializationNestedTypeLookupTable;
   if (!getIRGenOptions().ForceLoadSymbolName.empty())
     serializationOpts.AutolinkForceLoad = true;
 

lib/Frontend/ModuleInterfaceBuilder.cpp

@@ -347,8 +347,6 @@ bool ModuleInterfaceBuilder::buildSwiftModuleInternal(
     // optimization pipeline.
     SerializationOptions SerializationOpts;
     std::string OutPathStr = OutPath;
-    SerializationOpts.EnableNestedTypeLookupTable
-        = FEOpts.EnableSerializationNestedTypeLookupTable;
     SerializationOpts.OutputPath = OutPathStr.c_str();
     SerializationOpts.ModuleLinkName = FEOpts.ModuleLinkName;
     SerializationOpts.AutolinkForceLoad =

lib/Serialization/Deserialization.cpp

@@ -1465,10 +1465,6 @@ ModuleFile::resolveCrossReference(ModuleID MID, uint32_t pathLen) {
         Identifier memberName = getIdentifier(IID);
         pathTrace.addValue(memberName);
 
-        llvm::PrettyStackTraceString message{
-          "If you're seeing a crash here, try passing "
-            "-Xfrontend -disable-serialization-nested-type-lookup-table"};
-
         auto *baseType = cast<NominalTypeDecl>(values.front());
         ModuleDecl *extensionModule = M;
         if (!extensionModule)

lib/Serialization/Serialization.cpp

@@ -4832,8 +4832,7 @@ static void collectInterestingNestedDeclarations(
   }
 }
 
-void Serializer::writeAST(ModuleOrSourceFile DC,
-                          bool enableNestedTypeLookupTable) {
+void Serializer::writeAST(ModuleOrSourceFile DC) {
   DeclTable topLevelDecls, operatorDecls, operatorMethodDecls;
   DeclTable precedenceGroupDecls;
   ObjCMethodTable objcMethods;
@@ -4984,8 +4983,7 @@ void Serializer::writeAST(ModuleOrSourceFile DC,
     index_block::ObjCMethodTableLayout ObjCMethodTable(Out);
     writeObjCMethodTable(ObjCMethodTable, objcMethods);
 
-    if (enableNestedTypeLookupTable &&
-        !nestedTypeDecls.empty()) {
+    if (!nestedTypeDecls.empty()) {
       index_block::NestedTypeDeclsLayout NestedTypeDeclsTable(Out);
       writeNestedTypeDeclsTable(NestedTypeDeclsTable, nestedTypeDecls);
     }
@@ -5041,7 +5039,7 @@ void Serializer::writeToStream(raw_ostream &os, ModuleOrSourceFile DC,
     S.writeHeader(options);
     S.writeInputBlock(options);
     S.writeSIL(SILMod, options.SerializeAllSIL);
-    S.writeAST(DC, options.EnableNestedTypeLookupTable);
+    S.writeAST(DC);
   }
 
   S.writeToStream(os);

lib/Serialization/Serialization.h

@@ -370,8 +370,7 @@ class Serializer : public SerializerBase {
   void writeSIL(const SILModule *M, bool serializeAllSIL);
 
   /// Top-level entry point for serializing a module.
-  void writeAST(ModuleOrSourceFile DC,
-                bool enableNestedTypeLookupTable);
+  void writeAST(ModuleOrSourceFile DC);
 
   using SerializerBase::SerializerBase;
   using SerializerBase::writeToStream;

test/Serialization/multi-file-nested-type-simple.swift

@@ -7,17 +7,9 @@
 // Switch the order of the files.
 // RUN: %target-swift-frontend -emit-module -module-name Multi %t/multi-file-2.swiftmodule %t/multi-file.swiftmodule -o %t -print-stats 2>&1 | %FileCheck %s
 
-// RUN: %target-swift-frontend -emit-module -module-name Multi -o %t/multi-file.swiftmodule -primary-file %s %S/Inputs/multi-file-nested-types.swift -disable-serialization-nested-type-lookup-table
-// RUN: %target-swift-frontend -emit-module -module-name Multi -o %t/multi-file-2.swiftmodule %s -primary-file %S/Inputs/multi-file-nested-types.swift -disable-serialization-nested-type-lookup-table
-
-// RUN: %target-swift-frontend -emit-module -module-name Multi %t/multi-file.swiftmodule %t/multi-file-2.swiftmodule -o %t -print-stats 2>&1 | %FileCheck -check-prefix=DISABLED %s
-// RUN: %target-swift-frontend -emit-module -module-name Multi %t/multi-file-2.swiftmodule %t/multi-file.swiftmodule -o %t -print-stats 2>&1 | %FileCheck -check-prefix=DISABLED %s
-
 // REQUIRES: asserts
 
 // CHECK: 4 Serialization - # of nested types resolved without full lookup
-// DISABLED: Statistics
-// DISABLED-NOT: nested types resolved without full lookup
 
 public func useTypes(
   _: Outer.Inner,