Use SmallVectorImpl& instead of SmallVector to avoid repeating small vector size.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186098 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 1d5e5fb..69beaaf 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -1380,7 +1380,7 @@
 ///
 static bool
 CollectAddOperandsWithScales(DenseMap<const SCEV *, APInt> &M,
-                             SmallVector<const SCEV *, 8> &NewOps,
+                             SmallVectorImpl<const SCEV *> &NewOps,
                              APInt &AccumulatedConstant,
                              const SCEV *const *Ops, size_t NumOperands,
                              const APInt &Scale,