Use unique_ptr

[jgalenson]

Summary

Is this the best way to create the MCInstrAnalysis? Is there some way of reusing an existing one?

[pcc]

LGTM

I think this is the way that you are supposed to do it. It's the way that we're doing it elsewhere.
http://llvm-cs.pcc.me.uk/?q=createMCInstrAnalysis

[jgalenson]

In D51230#1212854, @pcc wrote:

LGTM

I think this is the way that you are supposed to do it. It's the way that we're doing it elsewhere.
http://llvm-cs.pcc.me.uk/?q=createMCInstrAnalysis

Yeah, that's why I added this. I was just wondering if there was some better way.

Thanks. I'll commit it now.

[vitalybuka]

Also https://reviews.llvm.org/rL340654

[jgalenson]

Thanks.

lib/Object/ELFObjectFile.cpp

case Triple::x86_64:
       JumpSlotReloc = ELF::R_X86_64_JUMP_SLOT;
       break;
     case Triple::aarch64:
       JumpSlotReloc = ELF::R_AARCH64_JUMP_SLOT;
       break;
     default:
       return {};
   }
-  const auto *MIA = T->createMCInstrAnalysis(T->createMCInstrInfo());
+  std::unique_ptr<const MCInstrAnalysis> MIA(
+      T->createMCInstrAnalysis(T->createMCInstrInfo()));
   if (!MIA)
     return {};
   Optional<SectionRef> Plt = None, RelaPlt = None, GotPlt = None;
   for (const SectionRef &Section : sections()) {
     StringRef Name;
     if (Section.getName(Name))
       continue;
     if (Name == ".plt")