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 { |
47 | BoundedRepeatSummary(void) : repeatMin(0), repeatMax(depth::infinity()) {} |
48 | 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 | } |
53 | 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 | |