Move setName after accessing Name.

[ioeric]

Summary

lib/IR/AutoUpgrade.cpp:348 and lib/IR/AutoUpgrade.cpp:350 upset sanitizer.

[bkramer]

lib/IR/AutoUpgrade.cpp

351 ↗

(On Diff #63236)

Can we just move the setName call below the accesses to Name? I think that would be simpler and avoids the string copy.

[ioeric]

• Move setName after accessing Name

llvm/trunk/lib/IR/AutoUpgrade.cpp

static bool UpgradeX86IntrinsicsWith8BitMask(Function *F, Intrinsic::ID IID,
   NewFn = Intrinsic::getDeclaration(F->getParent(), IID);
   return true;
 }
 
 static bool UpgradeIntrinsicFunction1(Function *F, Function *&NewFn) {
   assert(F && "Illegal to upgrade a non-existent Function.");
 
   // Quickly eliminate it, if it's not a candidate.
-  StringRef Name = F->getName();
+  // Make a copy of the name so that we don't need to worry about the life-time
+  // of StringRef.
+  std::string NameStr = F->getName().str();
+  StringRef Name = NameStr;
   if (Name.size() <= 8 || !Name.startswith("llvm."))
     return false;
   Name = Name.substr(5); // Strip off "llvm."
 
   switch (Name[0]) {
   default: break;
   case 'a': {
     if (Name.startswith("arm.neon.vclz")) {