[llvm] Remove unused local variables (NFC) (#167106)

Identified with bugprone-unused-local-non-trivial-variable.

Author: kazutakahirata

llvm/lib/CAS/UnifiedOnDiskCache.cpp

@@ -331,8 +331,6 @@ Expected<ValidationResult> UnifiedOnDiskCache::validateIfNeeded(
     if (Error E = getBootTime().moveInto(BootTime))
       return std::move(E);
 
-  std::string LogValidationError;
-
   if (ValidationBootTime == BootTime && !ForceValidation)
     return ValidationResult::Skipped;
 

llvm/lib/CodeGen/WindowsSecureHotPatching.cpp

@@ -461,8 +461,6 @@ static bool searchConstantExprForGlobalVariables(
     Value *V, SmallDenseMap<GlobalVariable *, Value *> &GVLoadMap,
     SmallVector<GlobalVariableUse> &GVUses) {
 
-  SmallVector<Value *, 8> ReplacedOperands;
-
   if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
     if (globalVariableNeedsRedirect(GV)) {
       GVLoadMap[GV] = nullptr;

llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp

@@ -1051,7 +1051,6 @@ bool LowOverheadLoop::ValidateLiveOuts() {
       // check where it gets its false lanes from, if any.
       int InactiveIdx = findVPTInactiveOperandIdx(*MI);
       if (InactiveIdx != -1) {
-        SmallPtrSet<MachineInstr *, 2> Defs;
         MachineInstr *FalseSrc = RDI.getUniqueReachingMIDef(
             MI, MI->getOperand(InactiveIdx).getReg());
         if (FalseSrc) {

llvm/lib/Transforms/IPO/SampleProfile.cpp

@@ -2293,7 +2293,6 @@ bool SampleProfileLoader::runOnFunction(Function &F,
   // count value.
   if (!F.getEntryCount())
     F.setEntryCount(ProfileCount(initialEntryCount, Function::PCT_Real));
-  std::unique_ptr<OptimizationRemarkEmitter> OwnedORE;
   auto &FAM = AM.getResult<FunctionAnalysisManagerModuleProxy>(*F.getParent())
                   .getManager();
   ORE = &FAM.getResult<OptimizationRemarkEmitterAnalysis>(F);

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -5368,7 +5368,6 @@ class BoUpSLP {
           Lane = P.first->ReorderIndices[Lane];
         assert(Lane < static_cast<int>(P.first->Scalars.size()) &&
                "Couldn't find extract lane");
-        SmallVector<unsigned> OpIndices;
         for (unsigned OpIdx :
              seq<unsigned>(::getNumberOfPotentiallyCommutativeOps(
                  P.first->getMainOp()))) {
@@ -8815,7 +8814,6 @@ void BoUpSLP::buildExternalUses(
     const ExtraValueToDebugLocsMap &ExternallyUsedValues) {
   const size_t NumVectScalars = ScalarToTreeEntries.size() + 1;
   DenseMap<Value *, unsigned> ScalarToExtUses;
-  SmallPtrSet<Value *, 4> ExternalUsers;
   // Collect the values that we need to extract from the tree.
   for (auto &TEPtr : VectorizableTree) {
     TreeEntry *Entry = TEPtr.get();