1 /* 2 * Copyright (c) 2015-2016, Intel Corporation 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * * Redistributions of source code must retain the above copyright notice, 8 * this list of conditions and the following disclaimer. 9 * * Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * * Neither the name of Intel Corporation nor the names of its contributors 13 * may be used to endorse or promote products derived from this software 14 * without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /** \file 30 * \brief Miscellaneous optimisations. 31 */ 32 33 #ifndef NG_MISC_OPT_H 34 #define NG_MISC_OPT_H 35 36 #include <map> 37 #include <vector> 38 39 #include "ng_holder.h" 40 #include "som/som.h" 41 #include "util/depth.h" 42 43 namespace ue2 { 44 45 /** Small structure describing the bounds on a repeat. */ 46 struct BoundedRepeatSummary { BoundedRepeatSummaryBoundedRepeatSummary47 BoundedRepeatSummary(void) : repeatMin(0), repeatMax(depth::infinity()) {} BoundedRepeatSummaryBoundedRepeatSummary48 BoundedRepeatSummary(const depth &min_in, const depth &max_in) 49 : repeatMin(min_in), repeatMax(max_in) { 50 assert(repeatMin <= repeatMax); 51 assert(repeatMax.is_reachable()); 52 } unboundedBoundedRepeatSummary53 bool unbounded(void) const { return repeatMax.is_infinite(); } 54 55 depth repeatMin; //!< minimum repeat bound. 56 depth repeatMax; //!< maximum repeat bound. 57 }; 58 59 /* returns true if anything changed */ 60 bool improveGraph(NGHolder &g, som_type som); 61 62 /** Sometimes the reach of a vertex is greater than it needs to be to reduce 63 * stop chars for the benefit of the rest of our code base (accel, etc). In 64 * these circumstances, we can treat the reach as the smaller one as 65 * the graphs are equivalent. */ 66 CharReach reduced_cr(NFAVertex v, const NGHolder &g, 67 const std::map<NFAVertex, BoundedRepeatSummary> &br_cyclic); 68 69 std::vector<CharReach> reduced_cr(const NGHolder &g, 70 const std::map<NFAVertex, BoundedRepeatSummary> &br_cyclic); 71 72 /** Remove cyclic stars connected to start */ 73 bool mergeCyclicDotStars(NGHolder &g); 74 75 /** 76 * Given a cyclic state 'c' with a broad reach and a later state 'v' that is 77 * only reachable if c is still on, then any edges to a successor of a direct 78 * successor of c with reach a superset of v are redundant. 79 */ 80 bool prunePathsRedundantWithSuccessorOfCyclics(NGHolder &h, som_type som); 81 82 } // namespace ue2 83 84 #endif 85