Fix no-assert ununsed variable.

[rdhindsa]

Summary

These variables are unused in the no-assert build.

[MaskRay]

This fixes -Wunused-variable warnings in -DLLVM_ENABLE_ASSERTIONS=off builds. This can be submitted without review.

I think if you mention the original differential (Dxxxxx), the author may be notified when you push the commit. The Phabricator UI will also connect your commit with the original differential.

[fhahn]

LGTM thanks, in case you are waiting for approval in Phabricator. But as mentioned earlier, there's no need for patches like this to go through review.

llvm/lib/Analysis/LoopInfo.cpp

369

FWIW if Latch is not used elsewhere, it would be easier to just call getLoopLatch in the assert, rather than adding an unused variable to the scope.

[MaskRay]

@rdhindsa is waiting for the git commit permission. In the meantime, rG25e21a09b3f6 was committed to fix the -Wunused-variable problems.

llvm/lib/Analysis/LoopInfo.cpp

   return SE.isLoopInvariant(IndDesc.getStep(), this);
 }
 
 BranchInst *Loop::getLoopGuardBranch() const {
   if (!isLoopSimplifyForm())
     return nullptr;
 
   BasicBlock *Preheader = getLoopPreheader();
   BasicBlock *Latch = getLoopLatch();
+  (void)Latch;
   assert(Preheader && Latch &&
          "Expecting a loop with valid preheader and latch");
 
   // Loop should be in rotate form.
   if (!isRotated())
     return nullptr;
 
   // Disallow loops with more than one unique exit block, as we do not verify

llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp

         };
     forAllMIsUntilDef(*I, RegToRename, TRI, LdStLimit, UpdateMIs);
 
     // Make sure the register used for renaming is not used between the paired
     // instructions. That would trash the content before the new paired
     // instruction.
     for (auto &MI :
          iterator_range<MachineInstrBundleIterator<llvm::MachineInstr>>(
-             std::next(I), std::next(Paired)))
+             std::next(I), std::next(Paired))){
+      (void)MI;
       assert(all_of(MI.operands(),
                     [this, &RenameReg](const MachineOperand &MOP) {
                       return !MOP.isReg() || MOP.isDebug() ||
                              !TRI->regsOverlap(MOP.getReg(), *RenameReg);
                     }) &&
              "Rename register used between paired instruction, trashing the "
              "content");
+    }
   }
 
   // Insert our new paired instruction after whichever of the paired
   // instructions MergeForward indicates.
   MachineBasicBlock::iterator InsertionPoint = MergeForward ? Paired : I;
   // Also based on MergeForward is from where we copy the base register operand
   // so we get the flags compatible with the input code.
   const MachineOperand &BaseRegOp =