NFC: Fix variable only used in asserts by propagating the value.

[saugustine]

Summary

This fixes builds with assertions disabled that would otherwise
fail with unused variable warnings

[saugustine]

Committed as r375148.

[Xiangling_L]

Thank you for your fix!

llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp

 }
 
 /// EmitInstruction -- Print out a single PowerPC MI in Darwin syntax to
 /// the current output stream.
 ///
 void PPCAsmPrinter::EmitInstruction(const MachineInstr *MI) {
   MCInst TmpInst;
   const bool IsDarwin = TM.getTargetTriple().isOSDarwin();
-  const bool IsPPC64 = Subtarget->isPPC64();
   const bool IsAIX = Subtarget->isAIXABI();
   const Module *M = MF->getFunction().getParent();
   PICLevel::Level PL = M->getPICLevel();
 
 #ifndef NDEBUG
   // Validate that SPE and FPU are mutually exclusive in codegen
   if (!MI->isInlineAsm()) {
     for (const MachineOperand &MO: MI->operands()) {
const MCSymbolRefExpr::VariantKind VK =
         IsAIX ? MCSymbolRefExpr::VK_None : MCSymbolRefExpr::VK_PPC_TOC;
     const MCExpr *Exp =
         MCSymbolRefExpr::create(TOCEntry, VK, OutContext);
     TmpInst.getOperand(1) = MCOperand::createExpr(Exp);
     EmitToStreamer(*OutStreamer, TmpInst);
     return;
   }
   case PPC::ADDIStocHA: {
-    assert((IsAIX && !IsPPC64 && TM.getCodeModel() == CodeModel::Large) &&
+    assert((IsAIX && !Subtarget->isPPC64() &&
+            TM.getCodeModel() == CodeModel::Large) &&
            "This pseudo should only be selected for 32-bit large code model on"
            " AIX.");
 
     // Transform %rd = ADDIStocHA %rA, @sym(%r2)
     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, IsDarwin);
 
     // Change the opcode to ADDIS.
     TmpInst.setOpcode(PPC::ADDIS);
case PPC::ADDIStocHA: {
     const MCExpr *Exp = MCSymbolRefExpr::create(TOCEntry,
                                                 MCSymbolRefExpr::VK_PPC_U,
                                                 OutContext);
     TmpInst.getOperand(2) = MCOperand::createExpr(Exp);
     EmitToStreamer(*OutStreamer, TmpInst);
     return;
   }
   case PPC::LWZtocL: {
-    assert(IsAIX && !IsPPC64 && TM.getCodeModel() == CodeModel::Large &&
+    assert(IsAIX && !Subtarget->isPPC64() &&
+           TM.getCodeModel() == CodeModel::Large &&
            "This pseudo should only be selected for 32-bit large code model on"
            " AIX.");
 
     // Transform %rd = LWZtocL @sym, %rs.
     LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, IsDarwin);
 
     // Change the opcode to lwz.
     TmpInst.setOpcode(PPC::LWZ);