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

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

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")) {
if (IsX86 && Name.startswith("xop.vfrcz.sd") && F->arg_size() == 2) {
       F->setName(Name + ".old");
       NewFn = Intrinsic::getDeclaration(F->getParent(),
                                         Intrinsic::x86_xop_vfrcz_sd);
       return true;
     }
     if (IsX86 && (Name.startswith("avx512.mask.pslli.") ||
                   Name.startswith("avx512.mask.psrai.") ||
                   Name.startswith("avx512.mask.psrli."))) {
       F->setName("llvm.x86." + Name + ".old");
       Intrinsic::ID ShiftID;
       if (Name.slice(12, 16) == "psll")
         ShiftID = Name[18] == 'd' ? Intrinsic::x86_avx512_mask_psll_di_512
                                   : Intrinsic::x86_avx512_mask_psll_qi_512;
       else if (Name.slice(12, 16) == "psra")
         ShiftID = Name[18] == 'd' ? Intrinsic::x86_avx512_mask_psra_di_512
                                   : Intrinsic::x86_avx512_mask_psra_qi_512;
       else