Make early if conversion dependent upon the subtarget and add

a subtarget hook to enable. Unconditionally add to the pass pipeline
for targets that might want to use it. No functional change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@209340 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/PowerPC/PPCSubtarget.h

@@ -205,6 +205,8 @@ public:
                              TargetSubtargetInfo::AntiDepBreakMode& Mode,
                              RegClassVector& CriticalPathRCs) const override;
 
+  bool enableEarlyIfConversion() const override { return hasISEL(); }
+
   // Scheduling customization.
   bool enableMachineScheduler() const override;
   void overrideSchedPolicy(MachineSchedPolicy &Policy,