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mergepoints.h Go to the documentation of this file. // $Id: mergepoints.h,v 1.9 2003/08/07 23:14:26 pnav Exp $ // ---------------------------------------------------------------------- // // C-Breeze // C Compiler Framework // // Copyright (c) 2000 University of Texas at Austin // // Samuel Z. Guyer // Daniel A. Jimenez // Calvin Lin // // Permission is hereby granted, free of charge, to any person // obtaining a copy of this software and associated documentation // files (the "Software"), to deal in the Software without // restriction, including without limitation the rights to use, copy, // modify, merge, publish, distribute, sublicense, and/or sell copies // of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be // included in all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND // NONINFRINGEMENT. IN NO EVENT SHALL THE UNIVERSITY OF TEXAS AT // AUSTIN BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER // IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF // OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN // THE SOFTWARE. // // We acknowledge the C-to-C Translator from MIT Laboratory for // Computer Science for inspiring parts of the C-Breeze design. // // ---------------------------------------------------------------------- #ifndef CBZ_MERGEPOINTS_H #define CBZ_MERGEPOINTS_H #include "pointeroptions.h" #include "memoryblock.h" #include "proceduredb.h" // ------------------------------------------------------------ // mergePoints : Holds all the merge points for the system -- // essentially, all the phi functions. Each entry holds the list of // objects whose states should be merged at a particular point in the // program. // mergepoint_pair (df element, predecessors) : given a basic block, // we use the DFPreds class to find its dominance frontier. For each // element of the dominance frontier, we also return the list of basic // blocks that come immediately before that element. typedef pair< basicblockLocation *, basicblock_set > mergepoint_pair; typedef list< mergepoint_pair > mergepoint_list; typedef mergepoint_list::iterator mergepoint_list_p; // mergepoint_map : for each merge point, record the objects that need // to be merged there. typedef map< basicblockLocation *, memoryblock_set > mergepoint_map; typedef mergepoint_map::iterator mergepoint_map_p; class mergePoints : public mergepoint_map { private: procedureDB * Procedures; bool _debug; public: mergePoints(procedureDB * procedures, bool debug = false) : mergepoint_map(), Procedures(procedures), _debug(debug) {} // --- Given a list of definitions and their location, find the set // of merge points (dominance frontier) and record the objects at // those points. This is equivalent to the SSA process that adds phi // functions for a particular set of definitions. void add_merge_points(basicblockLocation * location_of_def, int last_stmt_num, const memoryblock_set & defs); // --- Find the dominance frontier for a particular program // point. We do this interprocedurally by searching up the call // stack until we find a suitable place for the merge. void find_merge_points(basicblockLocation * cur, mergepoint_list & merge_points); // --- Add a block to the list of blocks that need to be merged at // the given merge point. void add_block_to_merge_point(mergepoint_pair & merge_point, memoryBlock * block); // --- Lookup a merge point: given a particular basic block, see if // there are any objects to be merged at its entry. memoryblock_set * lookup_merge_point(basicblockLocation * where); // --- Print some statistics void stats(); }; #endif // CBZ_MERGEPOINTS_H

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