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/CalcSpillWeights.cpp b/lib/CodeGen/CalcSpillWeights.cpp
index 76bb3d1..5637f4e 100644
--- a/lib/CodeGen/CalcSpillWeights.cpp
+++ b/lib/CodeGen/CalcSpillWeights.cpp
@@ -166,8 +166,7 @@
   // FIXME: this gets much more complicated once we support non-trivial
   // re-materialization.
   bool isLoad = false;
-  SmallVector<LiveInterval*, 4> spillIs;
-  if (lis_.isReMaterializable(li, spillIs, isLoad)) {
+  if (lis_.isReMaterializable(li, 0, isLoad)) {
     if (isLoad)
       totalWeight *= 0.9F;
     else