Change 'TypeCache' from being an std::map to a llvm::DenseMap.  This reduces codegen time
on one .i file from 403.gcc by 0.5%.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@99823 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGDebugInfo.h b/lib/CodeGen/CGDebugInfo.h
index 47a4620..3a9a4cc 100644
--- a/lib/CodeGen/CGDebugInfo.h
+++ b/lib/CodeGen/CGDebugInfo.h
@@ -53,7 +53,7 @@
   
   /// TypeCache - Cache of previously constructed Types.
   // FIXME: Eliminate this map.  Be careful of iterator invalidation.
-  std::map<void *, llvm::WeakVH> TypeCache;
+  llvm::DenseMap<void *, llvm::WeakVH> TypeCache;
 
   bool BlockLiteralGenericSet;
   llvm::DIType BlockLiteralGeneric;