Use SmallVectorImpl::iterator/const_iterator instead of SmallVector to avoid specifying the vector size.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185509 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LexicalScopes.cpp b/lib/CodeGen/LexicalScopes.cpp
index 6ea0aa4..f7ba125 100644
--- a/lib/CodeGen/LexicalScopes.cpp
+++ b/lib/CodeGen/LexicalScopes.cpp
@@ -220,7 +220,7 @@
     LexicalScope *WS = WorkStack.back();
     const SmallVectorImpl<LexicalScope *> &Children = WS->getChildren();
     bool visitedChildren = false;
-    for (SmallVector<LexicalScope *, 4>::const_iterator SI = Children.begin(),
+    for (SmallVectorImpl<LexicalScope *>::const_iterator SI = Children.begin(),
            SE = Children.end(); SI != SE; ++SI) {
       LexicalScope *ChildScope = *SI;
       if (!ChildScope->getDFSOut()) {
@@ -280,7 +280,7 @@
   }
 
   SmallVectorImpl<InsnRange> &InsnRanges = Scope->getRanges();
-  for (SmallVector<InsnRange, 4>::iterator I = InsnRanges.begin(),
+  for (SmallVectorImpl<InsnRange>::iterator I = InsnRanges.begin(),
          E = InsnRanges.end(); I != E; ++I) {
     InsnRange &R = *I;
     MBBs.insert(R.first->getParent());