[Analysis, CodeGen, DebugInfo] Use StringRef::operator== instead of StringRef::equals (NFC) (#91304)

I'm planning to remove StringRef::equals in favor of
StringRef::operator==.

- StringRef::operator==/!= outnumber StringRef::equals by a factor of
  53 under llvm/ in terms of their usage.

- The elimination of StringRef::equals brings StringRef closer to
  std::string_view, which has operator== but not equals.

- S == "foo" is more readable than S.equals("foo"), especially for
  !Long.Expression.equals("str") vs Long.Expression != "str".

Author: kazutakahirata

llvm/lib/Analysis/BlockFrequencyInfo.cpp

@@ -188,12 +188,11 @@ void BlockFrequencyInfo::calculate(const Function &F,
     BFI.reset(new ImplType);
   BFI->calculate(F, BPI, LI);
   if (ViewBlockFreqPropagationDAG != GVDT_None &&
-      (ViewBlockFreqFuncName.empty() ||
-       F.getName().equals(ViewBlockFreqFuncName))) {
+      (ViewBlockFreqFuncName.empty() || F.getName() == ViewBlockFreqFuncName)) {
     view();
   }
   if (PrintBFI &&
-      (PrintBFIFuncName.empty() || F.getName().equals(PrintBFIFuncName))) {
+      (PrintBFIFuncName.empty() || F.getName() == PrintBFIFuncName)) {
     print(dbgs());
   }
 }

llvm/lib/Analysis/BranchProbabilityInfo.cpp

@@ -1273,9 +1273,8 @@ void BranchProbabilityInfo::calculate(const Function &F, const LoopInfo &LoopI,
   EstimatedBlockWeight.clear();
   SccI.reset();
 
-  if (PrintBranchProb &&
-      (PrintBranchProbFuncName.empty() ||
-       F.getName().equals(PrintBranchProbFuncName))) {
+  if (PrintBranchProb && (PrintBranchProbFuncName.empty() ||
+                          F.getName() == PrintBranchProbFuncName)) {
     print(dbgs());
   }
 }

llvm/lib/Analysis/LoopInfo.cpp

@@ -1032,7 +1032,7 @@ MDNode *llvm::findOptionMDForLoopID(MDNode *LoopID, StringRef Name) {
     if (!S)
       continue;
     // Return the operand node if MDString holds expected metadata.
-    if (Name.equals(S->getString()))
+    if (Name == S->getString())
       return MD;
   }
 

llvm/lib/Analysis/MemoryProfileInfo.cpp

@@ -86,9 +86,9 @@ AllocationType llvm::memprof::getMIBAllocType(const MDNode *MIB) {
   // types that can be applied based on the allocation profile data.
   auto *MDS = dyn_cast<MDString>(MIB->getOperand(1));
   assert(MDS);
-  if (MDS->getString().equals("cold")) {
+  if (MDS->getString() == "cold") {
     return AllocationType::Cold;
-  } else if (MDS->getString().equals("hot")) {
+  } else if (MDS->getString() == "hot") {
     return AllocationType::Hot;
   }
   return AllocationType::NotCold;

llvm/lib/CodeGen/MIRSampleProfile.cpp

@@ -372,7 +372,7 @@ bool MIRProfileLoaderPass::runOnMachineFunction(MachineFunction &MF) {
   MF.RenumberBlocks();
   if (ViewBFIBefore && ViewBlockLayoutWithBFI != GVDT_None &&
       (ViewBlockFreqFuncName.empty() ||
-       MF.getFunction().getName().equals(ViewBlockFreqFuncName))) {
+       MF.getFunction().getName() == ViewBlockFreqFuncName)) {
     MBFI->view("MIR_Prof_loader_b." + MF.getName(), false);
   }
 
@@ -382,7 +382,7 @@ bool MIRProfileLoaderPass::runOnMachineFunction(MachineFunction &MF) {
 
   if (ViewBFIAfter && ViewBlockLayoutWithBFI != GVDT_None &&
       (ViewBlockFreqFuncName.empty() ||
-       MF.getFunction().getName().equals(ViewBlockFreqFuncName))) {
+       MF.getFunction().getName() == ViewBlockFreqFuncName)) {
     MBFI->view("MIR_prof_loader_a." + MF.getName(), false);
   }
 

llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp

@@ -198,12 +198,11 @@ void MachineBlockFrequencyInfo::calculate(
     MBFI.reset(new ImplType);
   MBFI->calculate(F, MBPI, MLI);
   if (ViewMachineBlockFreqPropagationDAG != GVDT_None &&
-      (ViewBlockFreqFuncName.empty() ||
-       F.getName().equals(ViewBlockFreqFuncName))) {
+      (ViewBlockFreqFuncName.empty() || F.getName() == ViewBlockFreqFuncName)) {
     view("MachineBlockFrequencyDAGS." + F.getName());
   }
   if (PrintMachineBlockFreq &&
-      (PrintBFIFuncName.empty() || F.getName().equals(PrintBFIFuncName))) {
+      (PrintBFIFuncName.empty() || F.getName() == PrintBFIFuncName)) {
     MBFI->print(dbgs());
   }
 }

llvm/lib/CodeGen/MachineBlockPlacement.cpp

@@ -3500,7 +3500,7 @@ bool MachineBlockPlacement::runOnMachineFunction(MachineFunction &MF) {
   }
   if (ViewBlockLayoutWithBFI != GVDT_None &&
       (ViewBlockFreqFuncName.empty() ||
-       F->getFunction().getName().equals(ViewBlockFreqFuncName))) {
+       F->getFunction().getName() == ViewBlockFreqFuncName)) {
     if (RenumberBlocksBeforeView)
       MF.RenumberBlocks();
     MBFI->view("MBP." + MF.getName(), false);

llvm/lib/CodeGen/TargetLoweringBase.cpp

@@ -2249,7 +2249,7 @@ static int getOpEnabled(bool IsSqrt, EVT VT, StringRef Override) {
     if (IsDisabled)
       RecipType = RecipType.substr(1);
 
-    if (RecipType.equals(VTName) || RecipType.equals(VTNameNoSize))
+    if (RecipType == VTName || RecipType == VTNameNoSize)
       return IsDisabled ? TargetLoweringBase::ReciprocalEstimate::Disabled
                         : TargetLoweringBase::ReciprocalEstimate::Enabled;
   }
@@ -2299,7 +2299,7 @@ static int getOpRefinementSteps(bool IsSqrt, EVT VT, StringRef Override) {
       continue;
 
     RecipType = RecipType.substr(0, RefPos);
-    if (RecipType.equals(VTName) || RecipType.equals(VTNameNoSize))
+    if (RecipType == VTName || RecipType == VTNameNoSize)
       return RefSteps;
   }
 

llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp

@@ -1036,7 +1036,7 @@ MCSection *TargetLoweringObjectFileELF::getSectionForMachineBasicBlock(
   // name, or a unique ID for the section.
   SmallString<128> Name;
   StringRef FunctionSectionName = MBB.getParent()->getSection()->getName();
-  if (FunctionSectionName.equals(".text") ||
+  if (FunctionSectionName == ".text" ||
       FunctionSectionName.starts_with(".text.")) {
     // Function is in a regular .text section.
     StringRef FunctionName = MBB.getParent()->getName();

llvm/lib/DebugInfo/LogicalView/Core/LVOptions.cpp

@@ -512,7 +512,7 @@ bool LVPatterns::matchPattern(StringRef Input, const LVMatchInfo &MatchInfo) {
   for (const LVMatch &Match : MatchInfo) {
     switch (Match.Mode) {
     case LVMatchMode::Match:
-      Matched = Input.equals(Match.Pattern);
+      Matched = Input == Match.Pattern;
       break;
     case LVMatchMode::NoCase:
       Matched = Input.equals_insensitive(Match.Pattern);