[MachineScheduler] Put SchedRegion in an anonymous namespace.

[bevinh]

Summary

It pollutes the global namespace otherwise.

[javed.absar]

lib/CodeGen/MachineScheduler.cpp

457

Please consider adding " // end anonymous namespace"
as is done with other such instances

[jonpa]

LGTM - thanks. /Jonas

lib/CodeGen/MachineScheduler.cpp

 static bool isSchedBoundary(MachineBasicBlock::iterator MI,
                             MachineBasicBlock *MBB,
                             MachineFunction *MF,
                             const TargetInstrInfo *TII) {
   return MI->isCall() || TII->isSchedulingBoundary(*MI, MBB, *MF);
 }
 
 /// A region of an MBB for scheduling.
+namespace {
 struct SchedRegion {
   /// RegionBegin is the first instruction in the scheduling region, and
   /// RegionEnd is either MBB->end() or the scheduling boundary after the
   /// last instruction in the scheduling region. These iterators cannot refer
   /// to instructions outside of the identified scheduling region because
   /// those may be reordered before scheduling this region.
   MachineBasicBlock::iterator RegionBegin;
   MachineBasicBlock::iterator RegionEnd;
   unsigned NumRegionInstrs;
   SchedRegion(MachineBasicBlock::iterator B, MachineBasicBlock::iterator E,
               unsigned N) :
     RegionBegin(B), RegionEnd(E), NumRegionInstrs(N) {}
 };
+}
 
 typedef SmallVector<SchedRegion, 16> MBBRegionsVector;
 static void
 getSchedRegions(MachineBasicBlock *MBB,
                 MBBRegionsVector &Regions,
                 bool RegionsTopDown) {
   MachineFunction *MF = MBB->getParent();
   const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();