[DviceSanitizer][Coverity] Fix auto-copy issues (#17794)

Fix Coverity reported auto-copy issues.

Author: yingcong-wu

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

@@ -4459,7 +4459,7 @@ void FunctionStackPoisoner::processStaticAllocas() {
     AI->replaceAllUsesWith(NewAllocaPtr);
   }
 
-  auto TargetTriple = Triple(F.getParent()->getTargetTriple());
+  const auto &TargetTriple = Triple(F.getParent()->getTargetTriple());
 
   // The left-most redzone has enough space for at least 4 pointers.
   Value *BasePlus0 = IRB.CreateIntToPtr(LocalStackBase, IntptrPtrTy);

llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp

@@ -783,7 +783,7 @@ class MemorySanitizerOnSpirv {
 public:
   MemorySanitizerOnSpirv(Module &M)
       : M(M), C(M.getContext()), DL(M.getDataLayout()) {
-    auto TargetTriple = Triple(M.getTargetTriple());
+    const auto &TargetTriple = Triple(M.getTargetTriple());
     IsSPIRV = TargetTriple.isSPIROrSPIRV();
 
     IntptrTy = DL.getIntPtrType(C);
@@ -1250,7 +1250,7 @@ PreservedAnalyses MemorySanitizerPass::run(Module &M,
   if (checkIfAlreadyInstrumented(M, "nosanitize_memory"))
     return PreservedAnalyses::all();
   bool Modified = false;
-  auto TargetTriple = Triple(M.getTargetTriple());
+  const auto &TargetTriple = Triple(M.getTargetTriple());
 
   if (!Options.Kernel && !TargetTriple.isSPIROrSPIRV()) {
     insertModuleCtor(M);