Enable ODR uniquing of DITypes in more places

[tejohnson]

Summary

This is a follow-on to apply Duncan's new DIType ODR uniquing from
r266549 and r266713 in more places.

Enable enableDebugTypeODRUniquing() for ThinLTO backends invoked via
libLTO, similar to the way r266549 enabled this for ThinLTO backend
threads launched from gold-plugin.

Also enable enableDebugTypeODRUniquing in opt, similar to the way
r266549 enabled this for llvm-link (on by default, can be disabled with
new -disable-debug-info-type-map option), since we may perform ThinLTO
importing from opt.

[mehdi_amini]

lib/LTO/ThinLTOCodeGenerator.cpp

524 ↗

(On Diff #54197)

This is the "CodeGen only" loop, won't import anything I don't think it matters here, but see below.

577–578 ↗

(On Diff #54197)

Here instead?

[tejohnson]

lib/LTO/ThinLTOCodeGenerator.cpp

577–578 ↗

(On Diff #54197)

Ack, yes, it should be here. Will move down here and retest before committing.

llvm/trunk/lib/LTO/ThinLTOCodeGenerator.cpp

void ThinLTOCodeGenerator::run() {
   // Parallel optimizer + codegen
   {
     ThreadPool Pool(ThreadCount);
     int count = 0;
     for (auto &ModuleBuffer : Modules) {
       Pool.async([&](int count) {
         LLVMContext Context;
         Context.setDiscardValueNames(LTODiscardValueNames);
+        Context.enableDebugTypeODRUniquing();
         auto ModuleIdentifier = ModuleBuffer.getBufferIdentifier();
 
         DenseMap<GlobalValue::GUID, GlobalValue::LinkageTypes> ResolvedODR;
         ResolveODR(*Index, ModuleToDefinedGVSummaries[ModuleIdentifier],
                    ModuleIdentifier, ResolvedODR);
 
         // Parse module now
         auto TheModule = loadModuleFromBuffer(ModuleBuffer, Context, false);

llvm/trunk/tools/opt/opt.cpp

 
 static cl::opt<bool>
 NoVerify("disable-verify", cl::desc("Do not run the verifier"), cl::Hidden);
 
 static cl::opt<bool>
 VerifyEach("verify-each", cl::desc("Verify after each transform"));
 
 static cl::opt<bool>
+    DisableDITypeMap("disable-debug-info-type-map",
+                     cl::desc("Don't use a uniquing type map for debug info"));
+
+static cl::opt<bool>
 StripDebug("strip-debug",
            cl::desc("Strip debugger symbol info from translation unit"));
 
 static cl::opt<bool>
 DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
 
 static cl::opt<bool>
 DisableOptimizations("disable-opt",
#endif
   if (AnalyzeOnly && NoOutput) {
     errs() << argv[0] << ": analyze mode conflicts with no-output mode.\n";
     return 1;
   }
 
   SMDiagnostic Err;
 
   Context.setDiscardValueNames(DiscardValueNames);
+  if (!DisableDITypeMap)
+    Context.enableDebugTypeODRUniquing();
 
   // Load the input module...
   std::unique_ptr<Module> M = parseIRFile(InputFilename, Err, Context);
 
   if (!M) {
     Err.print(argv[0], errs());
     return 1;
   }