1 | /* |
2 | * Copyright (c) 2015-2017, 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 Rose compile-time analysis for lookaround masks. |
31 | */ |
32 | #ifndef ROSE_ROSE_BUILD_LOOKAROUND_H |
33 | #define ROSE_ROSE_BUILD_LOOKAROUND_H |
34 | |
35 | #include "rose_graph.h" |
36 | #include "util/hash.h" |
37 | |
38 | #include <vector> |
39 | |
40 | /** \brief Max path number for multi-path lookaround. */ |
41 | #define MAX_LOOKAROUND_PATHS 8 |
42 | |
43 | namespace ue2 { |
44 | |
45 | class CharReach; |
46 | class RoseBuildImpl; |
47 | |
48 | /** \brief Lookaround entry prototype, describing the reachability at a given |
49 | * distance from the end of a role match. */ |
50 | struct LookEntry { |
51 | LookEntry() : offset(0) {} |
52 | LookEntry(s8 offset_in, const CharReach &reach_in) |
53 | : offset(offset_in), reach(reach_in) {} |
54 | s8 offset; //!< offset from role match location. |
55 | CharReach reach; //!< reachability at given offset. |
56 | |
57 | bool operator==(const LookEntry &other) const { |
58 | return offset == other.offset && reach == other.reach; |
59 | } |
60 | }; |
61 | |
62 | void findLookaroundMasks(const RoseBuildImpl &tbi, const RoseVertex v, |
63 | std::vector<LookEntry> &look_more); |
64 | |
65 | /** |
66 | * \brief If possible, render the prefix of the given vertex as a lookaround. |
67 | * |
68 | * Given a prefix, returns true (and fills the lookaround vector) if |
69 | * it can be satisfied with a lookaround alone. |
70 | */ |
71 | bool makeLeftfixLookaround(const RoseBuildImpl &build, const RoseVertex v, |
72 | std::vector<std::vector<LookEntry>> &lookaround); |
73 | |
74 | void mergeLookaround(std::vector<LookEntry> &lookaround, |
75 | const std::vector<LookEntry> &more_lookaround); |
76 | |
77 | } // namespace ue2 |
78 | |
79 | namespace std { |
80 | |
81 | template<> |
82 | struct hash<ue2::LookEntry> { |
83 | size_t operator()(const ue2::LookEntry &l) const { |
84 | return ue2::hash_all(l.offset, l.reach); |
85 | } |
86 | }; |
87 | |
88 | } // namespace std |
89 | |
90 | #endif // ROSE_ROSE_BUILD_LOOKAROUND_H |
91 | |