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

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186274 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopDeletion.cpp b/lib/Transforms/Scalar/LoopDeletion.cpp
index 0a40600..9e39d2e 100644
--- a/lib/Transforms/Scalar/LoopDeletion.cpp
+++ b/lib/Transforms/Scalar/LoopDeletion.cpp
@@ -51,8 +51,8 @@
     }
 
   private:
-    bool isLoopDead(Loop *L, SmallVector<BasicBlock*, 4> &exitingBlocks,
-                    SmallVector<BasicBlock*, 4> &exitBlocks,
+    bool isLoopDead(Loop *L, SmallVectorImpl<BasicBlock *> &exitingBlocks,
+                    SmallVectorImpl<BasicBlock *> &exitBlocks,
                     bool &Changed, BasicBlock *Preheader);
 
   };
@@ -77,8 +77,8 @@
 /// checked for unique exit and exiting blocks, and that the code is in LCSSA
 /// form.
 bool LoopDeletion::isLoopDead(Loop *L,
-                              SmallVector<BasicBlock*, 4> &exitingBlocks,
-                              SmallVector<BasicBlock*, 4> &exitBlocks,
+                              SmallVectorImpl<BasicBlock *> &exitingBlocks,
+                              SmallVectorImpl<BasicBlock *> &exitBlocks,
                               bool &Changed, BasicBlock *Preheader) {
   BasicBlock *exitBlock = exitBlocks[0];