Optimize string usage in the lexer

This speeds up the parsing stage >2x, mostly by minimizing string
construction and comparison where char comparison will do.

1 files changed, 6 insertions, 5 deletions

diff --git a/parse.h b/parse.h
index 59046bf3..4cc4f7b2 100644
--- a/parse.h
+++ b/parse.h
@@ -15,6 +15,7 @@
 #include <fstream>
 #include <iostream>
 #include <vector>
+#include <set>
 #include <stdexcept>
 #include <stdint.h>
 
@@ -78,19 +79,19 @@ public:
   void set_current_file (stapfile* f);
 
 private:
-  int input_get ();
-  void input_put (int);
+  inline int input_get ();
+  inline int input_peek (unsigned n=0);
   void input_put (const std::string&);
-  int input_peek (unsigned n=0);
-  std::istream& input;
   std::string input_name;
   std::string input_contents;
-  int input_pointer; // index into input_contents
+  const char *input_pointer; // index into input_contents
+  const char *input_end;
   unsigned cursor_suspend_count;
   unsigned cursor_line;
   unsigned cursor_column;
   systemtap_session& session;
   stapfile* current_file;
+  static std::set<std::string> keywords;
 };
 
 struct probe;