add a trivial line # cache to SourceMgr to make repeated queries to

FindLineNumber much faster when in sequence.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78693 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 1 deletions

diff --git a/include/llvm/Support/SourceMgr.h b/include/llvm/Support/SourceMgr.h
index 37cdc0a1f4..5b6f56b436 100644
--- a/include/llvm/Support/SourceMgr.h
+++ b/include/llvm/Support/SourceMgr.h
@@ -65,10 +65,14 @@ class SourceMgr {
   // include files in.
   std::vector<std::string> IncludeDirectories;
   
+  /// LineNoCache - This is a cache for line number queries, its implementation
+  /// is really private to SourceMgr.cpp.
+  mutable void *LineNoCache;
+  
   SourceMgr(const SourceMgr&);    // DO NOT IMPLEMENT
   void operator=(const SourceMgr&); // DO NOT IMPLEMENT
 public:
-  SourceMgr() {}
+  SourceMgr() : LineNoCache(0) {}
   ~SourceMgr();
   
   void setIncludeDirs(const std::vector<std::string> &Dirs) {