Fix unused variables in release build

[samtebbs]

Thank you @goncharov and @kadircet

llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp

for (auto &Block : LoLoop.getVPTBlocks()) {
     } else if (Insts.front()->getOpcode() == ARM::MVE_VPST) {
       // If this block starts with a VPST then attempt to merge it with the
       // preceeding un-merged VCMP into a VPT. This VCMP comes from a VPT
       // block that no longer exists
       MachineInstr *VPST = Insts.front();
       auto Next = ++MachineBasicBlock::iterator(VPST);
       assert(getVPTInstrPredicate(*Next) != ARMVCC::None &&
              "The instruction after a VPST must be predicated");
-
+      (void)Next;
       MachineInstr *VprDef = RDA->getUniqueReachingMIDef(VPST, ARM::VPR);
       if (VprDef && VCMPOpcodeToVPT(VprDef->getOpcode()) &&
           !LoLoop.ToRemove.contains(VprDef)) {
         MachineInstr *VCMP = VprDef;
         // The VCMP and VPST can only be merged if the VCMP's operands will have
         // the same values at the VPST
         if (RDA->hasSameReachingDef(VCMP, VPST, VCMP->getOperand(1).getReg()) &&
             RDA->hasSameReachingDef(VCMP, VPST, VCMP->getOperand(2).getReg())) {
-          bool IntermediateInstrsUseVPR =
-              std::any_of(++MachineBasicBlock::iterator(VCMP),
-                          MachineBasicBlock::iterator(VPST), hasVPRUse);
           // If the instruction after the VCMP is predicated then a different
           // code path is expected to have merged the VCMP and VPST already.
           // This assertion protects against changes to that behaviour
-          assert(!IntermediateInstrsUseVPR &&
+          assert(!std::any_of(++MachineBasicBlock::iterator(VCMP),
+                              MachineBasicBlock::iterator(VPST), hasVPRUse) &&
                  "Instructions between the VCMP and VPST are not expected to "
                  "be predicated");
           ReplaceVCMPWithVPT(VCMP, VPST);
           LLVM_DEBUG(dbgs() << "ARM Loops: Removing VPST: " << *VPST);
           LoLoop.ToRemove.insert(VPST);
         }
       }
     }