clang-format: Store pointers to seen formatting states.

As the memory ownership is handled by the SpecificBumpPtrAllocator
anyway, there is no need to duplicate states when inserting them into
the Seen-set. This leads to an improvement of ~10% on the benchmark
formatting file.

No functional changes intended.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@209422 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 471af1d5393eeca13dedacdf72e77b52cc3c8366..2821e4aa2c1f949bf0e13e36422543729184ce14 100644 (file)
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -1005,6 +1005,12 @@ private:
     return Style.ColumnLimit - (InPPDirective ? 2 : 0);
   }
 
+  struct CompareLineStatePointers {
+    bool operator()(LineState *obj1, LineState *obj2) const {
+      return *obj1 < *obj2;
+    }
+  };
+
   /// \brief Analyze the entire solution space starting from \p InitialState.
   ///
   /// This implements a variant of Dijkstra's algorithm on the graph that spans
@@ -1014,7 +1020,7 @@ private:
   ///
   /// If \p DryRun is \c false, directly applies the changes.
   unsigned analyzeSolutionSpace(LineState &InitialState, bool DryRun = false) {
-    std::set<LineState> Seen;
+    std::set<LineState *, CompareLineStatePointers> Seen;
 
     // Increasing count of \c StateNode items we have created. This is used to
     // create a deterministic order independent of the container.
@@ -1044,7 +1050,7 @@ private:
       if (Count > 10000)
         Node->State.IgnoreStackForComparison = true;
 
-      if (!Seen.insert(Node->State).second)
+      if (!Seen.insert(&Node->State).second)
         // State already examined with lower penalty.
         continue;