[code generation] added double-buffering

include/codegen/buffer_info.h

@@ -0,0 +1,34 @@
+#ifndef TDL_INCLUDE_CODEGEN_BUFFER_INFO_PASS_H
+#define TDL_INCLUDE_CODEGEN_BUFFER_INFO_PASS_H
+
+#include <set>
+#include <map>
+
+namespace tdl {
+
+namespace ir {
+  class module;
+  class value;
+}
+
+namespace codegen{
+
+class buffer_info_pass {
+public:
+  void run(ir::module &mod);
+  // queries
+  bool is_double(ir::value *x);
+  bool is_shared(ir::value *x);
+  ir::value *get_reference(ir::value *x);
+
+private:
+  std::set<ir::value*> shared_;
+  std::set<ir::value*> double_;
+  std::map<ir::value*, ir::value*> refs_;
+};
+
+
+}
+}
+
+#endif