Make SpillIs an optional pointer. Avoid creating a bunch of temporary SmallVectors.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127388 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/Spiller.cpp b/lib/CodeGen/Spiller.cpp
index fd38582..d9801a6 100644
--- a/lib/CodeGen/Spiller.cpp
+++ b/lib/CodeGen/Spiller.cpp
@@ -182,7 +182,7 @@
 
   void spill(LiveInterval *li,
              SmallVectorImpl<LiveInterval*> &newIntervals,
-             const SmallVectorImpl<LiveInterval*> &) {
+             const SmallVectorImpl<LiveInterval*>*) {
     // Ignore spillIs - we don't use it.
     trivialSpillEverywhere(li, newIntervals);
   }
@@ -212,7 +212,7 @@
   /// Falls back on LiveIntervals::addIntervalsForSpills.
   void spill(LiveInterval *li,
              SmallVectorImpl<LiveInterval*> &newIntervals,
-             const SmallVectorImpl<LiveInterval*> &spillIs) {
+             const SmallVectorImpl<LiveInterval*> *spillIs) {
     std::vector<LiveInterval*> added =
       lis->addIntervalsForSpills(*li, spillIs, loopInfo, *vrm);
     newIntervals.insert(newIntervals.end(), added.begin(), added.end());