[clang] [llvm] [ThinLTO] Support dead RTTI data elimination under -fno-split-lto-unit (PR #126336)

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git-clang-format --diff 4294fe173e9696a4c090857fa0766cd44c1964dc 83b532a3382a07e472558b8813d43a6f51801423 --extensions h,cpp -- clang/test/CodeGenCXX/typeid-type-test.cpp llvm/include/llvm/Support/LibCXXABI.h llvm/include/llvm/Transforms/IPO/DeadRTTIElimination.h llvm/lib/Support/LibCXXABI.cpp llvm/lib/Transforms/IPO/DeadRTTIElimination.cpp clang/lib/CodeGen/ItaniumCXXABI.cpp llvm/include/llvm/Analysis/TypeMetadataUtils.h llvm/include/llvm/AsmParser/LLParser.h llvm/include/llvm/AsmParser/LLToken.h llvm/include/llvm/Bitcode/LLVMBitCodes.h llvm/include/llvm/IR/ModuleSummaryIndex.h llvm/include/llvm/LTO/LTO.h llvm/lib/Analysis/ModuleSummaryAnalysis.cpp llvm/lib/Analysis/TypeMetadataUtils.cpp llvm/lib/AsmParser/LLLexer.cpp llvm/lib/AsmParser/LLParser.cpp llvm/lib/Bitcode/Reader/BitcodeReader.cpp llvm/lib/Bitcode/Writer/BitcodeWriter.cpp llvm/lib/IR/AsmWriter.cpp llvm/lib/LTO/LTO.cpp llvm/lib/LTO/LTOBackend.cpp
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diff --git a/llvm/include/llvm/LTO/LTO.h b/llvm/include/llvm/LTO/LTO.h
index 085e6eaddc..73b8974b35 100644
--- a/llvm/include/llvm/LTO/LTO.h
+++ b/llvm/include/llvm/LTO/LTO.h
@@ -529,7 +529,7 @@ private:
 
   Error checkPartiallySplit();
 
-  std::string & getTargetTriple() { return TargetTriple; }
+  std::string &getTargetTriple() { return TargetTriple; }
 
   void setTargetTriple(std::string TT) { TargetTriple = std::move(TT); }
 
diff --git a/llvm/include/llvm/Support/LibCXXABI.h b/llvm/include/llvm/Support/LibCXXABI.h
index 37f4b43f95..855aca5527 100644
--- a/llvm/include/llvm/Support/LibCXXABI.h
+++ b/llvm/include/llvm/Support/LibCXXABI.h
@@ -8,9 +8,9 @@ namespace llvm {
 
 class CXXABI {
 
-  virtual const char * getVTablePrefix() = 0;
-  virtual const char * getTypeNamePrefix() = 0;
-  virtual const char * getTypeInfoPrefix() = 0;
+  virtual const char *getVTablePrefix() = 0;
+  virtual const char *getTypeNamePrefix() = 0;
+  virtual const char *getTypeInfoPrefix() = 0;
 
 public:
   static std::unique_ptr<CXXABI> Create(Triple &TT);
@@ -32,9 +32,9 @@ public:
 
 class Itanium final : public CXXABI {
 
-  const char * getVTablePrefix() override { return "_ZTV"; }
-  const char * getTypeNamePrefix() override { return "_ZTS"; }
-  const char * getTypeInfoPrefix() override { return "_ZTI"; }
+  const char *getVTablePrefix() override { return "_ZTV"; }
+  const char *getTypeNamePrefix() override { return "_ZTS"; }
+  const char *getTypeInfoPrefix() override { return "_ZTI"; }
 
 public:
   virtual ~Itanium() {}
diff --git a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
index ec0aa81d05..a1778bf6e2 100644
--- a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
+++ b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
@@ -925,7 +925,8 @@ static bool hasNonVTableUsers(const User *U, CXXABI *ABI) {
   }
 
   // The virtual table type is either a struct of arrays. For example:
-  // @vtable = constant { [3 x ptr] } { [3 x ptr] [ ptr null, ptr @rtti, ptr @vf] }
+  // @vtable = constant { [3 x ptr] } { [3 x ptr] [ ptr null, ptr @rtti, ptr
+  // @vf] }
   //
   // In this case, the user of @rtti is an anonymous ConstantArray.
   // Therefore, if the user of the type information is anonymous,
@@ -959,8 +960,7 @@ static void analyzeRTTIVars(ModuleSummaryIndex &Index, const Module &M) {
       continue;
 
     if (hasNonVTableUsers(&GV, ABI.get())) {
-      std::string TypeName =
-          ABI->getTypeNameFromTypeInfo(GV.getName());
+      std::string TypeName = ABI->getTypeNameFromTypeInfo(GV.getName());
       const GlobalVariable *TypeNameGV = M.getNamedGlobal(TypeName);
       if (TypeNameGV)
         Index.addTypeIdAccessed(TypeNameGV->getName());
diff --git a/llvm/lib/LTO/LTO.cpp b/llvm/lib/LTO/LTO.cpp
index 49a0c31af5..a4c07acf96 100644
--- a/llvm/lib/LTO/LTO.cpp
+++ b/llvm/lib/LTO/LTO.cpp
@@ -53,9 +53,9 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetOptions.h"
 #include "llvm/Transforms/IPO.h"
+#include "llvm/Transforms/IPO/DeadRTTIElimination.h"
 #include "llvm/Transforms/IPO/MemProfContextDisambiguation.h"
 #include "llvm/Transforms/IPO/WholeProgramDevirt.h"
-#include "llvm/Transforms/IPO/DeadRTTIElimination.h"
 #include "llvm/Transforms/Utils/FunctionImportUtils.h"
 #include "llvm/Transforms/Utils/SplitModule.h"
 
@@ -1931,7 +1931,6 @@ Error LTO::runThinLTO(
     computeDeadSymbolsWithConstProp(ThinLTO.CombinedIndex, GUIDPreservedSymbols,
                                     IsPrevailing, Conf.OptLevel > 0);
 
-
   if (Conf.CombinedIndexHook &&
       !Conf.CombinedIndexHook(ThinLTO.CombinedIndex, GUIDPreservedSymbols))
     return Error::success();
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
index d0566f0d00..c094d1f166 100644
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -581,8 +581,8 @@ static void dropDeadSymbols(Module &Mod, const GVSummaryMapTy &DefinedGlobals,
   // themselves when possible.
   for (GlobalValue *GV : DeadGVs) {
     GV->removeDeadConstantUsers();
-    if (ABI && (ABI->isTypeInfo(GV->getName()) ||
-                            ABI->isTypeName(GV->getName()))) {
+    if (ABI &&
+        (ABI->isTypeInfo(GV->getName()) || ABI->isTypeName(GV->getName()))) {
       GV->replaceAllUsesWith(
           ConstantPointerNull::get(PointerType::get(Mod.getContext(), 0)));
       GV->eraseFromParent();
diff --git a/llvm/lib/Transforms/IPO/DeadRTTIElimination.cpp b/llvm/lib/Transforms/IPO/DeadRTTIElimination.cpp
index bef2f52cd4..4566973f2e 100644
--- a/llvm/lib/Transforms/IPO/DeadRTTIElimination.cpp
+++ b/llvm/lib/Transforms/IPO/DeadRTTIElimination.cpp
@@ -29,8 +29,7 @@ void DeadRTTIElimIndex::run() {
 
   for (auto &VI : ExportSummary) {
     StringRef GVSName = VI.second.U.Name;
-    if (!ABI->isVTable(GVSName) ||
-        TypeIdSlotMayLiveVTables.contains(GVSName) ||
+    if (!ABI->isVTable(GVSName) || TypeIdSlotMayLiveVTables.contains(GVSName) ||
         VI.second.SummaryList.empty())
       continue;
 

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https://github.com/llvm/llvm-project/pull/126336