Revert "[NFCI][Globals] In GlobalObjects::setSectionPrefix, do conditional up…"

This reverts commit 027bccc.

Author: mingmingl-llvm

llvm/include/llvm/IR/GlobalObject.h

@@ -121,10 +121,8 @@ class GlobalObject : public GlobalValue {
   /// appropriate default object file section.
   LLVM_ABI void setSection(StringRef S);
 
-  /// If existing prefix is different from \p Prefix, set it to \p Prefix. If \p
-  /// Prefix is empty, the set clears the existing metadata. Returns true if
-  /// section prefix changed and false otherwise.
-  LLVM_ABI bool setSectionPrefix(StringRef Prefix);
+  /// Set the section prefix for this global object.
+  LLVM_ABI void setSectionPrefix(StringRef Prefix);
 
   /// Get the section prefix for this global object.
   LLVM_ABI std::optional<StringRef> getSectionPrefix() const;

llvm/lib/CodeGen/CodeGenPrepare.cpp

@@ -583,23 +583,23 @@ bool CodeGenPrepare::_run(Function &F) {
   // if requested.
   if (BBSectionsGuidedSectionPrefix && BBSectionsProfileReader &&
       BBSectionsProfileReader->isFunctionHot(F.getName())) {
-    EverMadeChange |= F.setSectionPrefix("hot");
+    F.setSectionPrefix("hot");
   } else if (ProfileGuidedSectionPrefix) {
     // The hot attribute overwrites profile count based hotness while profile
     // counts based hotness overwrite the cold attribute.
     // This is a conservative behabvior.
     if (F.hasFnAttribute(Attribute::Hot) ||
         PSI->isFunctionHotInCallGraph(&F, *BFI))
-      EverMadeChange |= F.setSectionPrefix("hot");
+      F.setSectionPrefix("hot");
     // If PSI shows this function is not hot, we will placed the function
     // into unlikely section if (1) PSI shows this is a cold function, or
     // (2) the function has a attribute of cold.
     else if (PSI->isFunctionColdInCallGraph(&F, *BFI) ||
              F.hasFnAttribute(Attribute::Cold))
-      EverMadeChange |= F.setSectionPrefix("unlikely");
+      F.setSectionPrefix("unlikely");
     else if (ProfileUnknownInSpecialSection && PSI->hasPartialSampleProfile() &&
              PSI->isFunctionHotnessUnknown(F))
-      EverMadeChange |= F.setSectionPrefix("unknown");
+      F.setSectionPrefix("unknown");
   }
 
   /// This optimization identifies DIV instructions that can be

llvm/lib/CodeGen/StaticDataAnnotator.cpp

@@ -91,7 +91,8 @@ bool StaticDataAnnotator::runOnModule(Module &M) {
     if (SectionPrefix.empty())
       continue;
 
-    Changed |= GV.setSectionPrefix(SectionPrefix);
+    GV.setSectionPrefix(SectionPrefix);
+    Changed = true;
   }
 
   return Changed;

llvm/lib/IR/Globals.cpp

@@ -288,22 +288,10 @@ void GlobalObject::setSection(StringRef S) {
   setGlobalObjectFlag(HasSectionHashEntryBit, !S.empty());
 }
 
-bool GlobalObject::setSectionPrefix(StringRef Prefix) {
-  StringRef ExistingPrefix;
-  if (std::optional<StringRef> MaybePrefix = getSectionPrefix())
-    ExistingPrefix = *MaybePrefix;
-
-  if (ExistingPrefix == Prefix)
-    return false;
-
-  if (Prefix.empty()) {
-    setMetadata(LLVMContext::MD_section_prefix, nullptr);
-    return true;
-  }
+void GlobalObject::setSectionPrefix(StringRef Prefix) {
   MDBuilder MDB(getContext());
   setMetadata(LLVMContext::MD_section_prefix,
               MDB.createGlobalObjectSectionPrefix(Prefix));
-  return true;
 }
 
 std::optional<StringRef> GlobalObject::getSectionPrefix() const {

llvm/lib/Transforms/Instrumentation/MemProfUse.cpp

@@ -848,12 +848,13 @@ bool MemProfUsePass::annotateGlobalVariables(
     // So we just print out the static data section prefix in LLVM_DEBUG.
     if (Record && Record->AccessCount > 0) {
       ++NumOfMemProfHotGlobalVars;
-      Changed |= GVar.setSectionPrefix("hot");
+      GVar.setSectionPrefix("hot");
+      Changed = true;
       LLVM_DEBUG(dbgs() << "Global variable " << Name
                         << " is annotated as hot\n");
     } else if (DataAccessProf->isKnownColdSymbol(Name)) {
       ++NumOfMemProfColdGlobalVars;
-      Changed |= GVar.setSectionPrefix("unlikely");
+      GVar.setSectionPrefix("unlikely");
       Changed = true;
       LLVM_DEBUG(dbgs() << "Global variable " << Name
                         << " is annotated as unlikely\n");

llvm/unittests/IR/CMakeLists.txt

@@ -28,7 +28,6 @@ add_llvm_unittest(IRTests
   DominatorTreeBatchUpdatesTest.cpp
   DroppedVariableStatsIRTest.cpp
   FunctionTest.cpp
-  GlobalObjectTest.cpp
   PassBuilderCallbacksTest.cpp
   IRBuilderTest.cpp
   InstructionsTest.cpp