Fix for PR26690

I mistook BitVector::empty() to mean BitVector::count() == 0 and it does
not. Corrected the issue with the fix for PR26500.

llvm-svn: 261525

llvm/lib/Target/PowerPC/PPCFrameLowering.cpp

@@ -653,7 +653,7 @@ PPCFrameLowering::findScratchRegister(MachineBasicBlock *MBB,
 
   // Now that we've done our best to provide both registers, double check
   // whether we were unable to provide enough.
-  if (BV.empty() || (BV.count() < 2 && TwoUniqueRegsRequired))
+  if (BV.count() < TwoUniqueRegsRequired ? 2 : 1)
     return false;
 
   return true;