1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
/*
* Copyright (c) 2015-2017, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Intel Corporation nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/** \file
* \brief Shared build code for DFAs (McClellan, Haig).
*/
#ifndef NG_MCCLELLAN_INTERNAL_H
#define NG_MCCLELLAN_INTERNAL_H
#include "ue2common.h"
#include "nfa/mcclellancompile.h"
#include "nfagraph/ng_holder.h"
#include "util/charreach.h"
#include "util/graph_range.h"
#include "util/flat_containers.h"
#include <boost/dynamic_bitset.hpp>
#include <map>
#include <vector>
namespace ue2 {
struct raw_dfa;
/** Fills alpha, unalpha and returns alphabet size. */
u16 buildAlphabetFromEquivSets(const std::vector<CharReach> &esets,
std::array<u16, ALPHABET_SIZE> &alpha,
std::array<u16, ALPHABET_SIZE> &unalpha);
/** \brief Calculates an alphabet remapping based on the symbols which the
* graph discriminates on. Throws in some special DFA symbols as well. */
void calculateAlphabet(const NGHolder &g, std::array<u16, ALPHABET_SIZE> &alpha,
std::array<u16, ALPHABET_SIZE> &unalpha, u16 *alphasize);
void getFullTransitionFromState(const raw_dfa &n, u16 state,
u16 *out_table);
/** produce a map of states on which it is valid to receive tops */
void markToppableStarts(const NGHolder &g, const flat_set<NFAVertex> &unused,
bool single_trigger,
const std::vector<std::vector<CharReach>> &triggers,
boost::dynamic_bitset<> *out);
/**
* \brief Returns a set of start vertices that will not participate in an
* implementation of this graph. These are either starts with no successors or
* starts which are redundant with startDs.
*/
flat_set<NFAVertex> getRedundantStarts(const NGHolder &g);
template<typename autom>
void transition_graph(autom &nfa, const std::vector<NFAVertex> &vByStateId,
const typename autom::StateSet &in,
typename autom::StateSet *next) {
typedef typename autom::StateSet StateSet;
const NGHolder &graph = nfa.graph;
const auto &unused = nfa.unused;
const auto &alpha = nfa.alpha;
const StateSet &squash = nfa.squash;
const std::map<u32, StateSet> &squash_mask = nfa.squash_mask;
const std::vector<CharReach> &cr_by_index = nfa.cr_by_index;
for (symbol_t s = 0; s < nfa.alphasize; s++) {
next[s].reset();
}
/* generate top transitions, false -> top = selfloop */
bool top_allowed = is_triggered(graph);
StateSet succ = nfa.dead;
for (size_t i = in.find_first(); i != in.npos; i = in.find_next(i)) {
NFAVertex u = vByStateId[i];
for (const auto &v : adjacent_vertices_range(u, graph)) {
if (contains(unused, v)) {
continue;
}
succ.set(graph[v].index);
}
if (top_allowed && !nfa.toppable.test(i)) {
/* we don't need to generate a top at this location as we are in
* an nfa state which cannot be on when a trigger arrives. */
top_allowed = false;
}
}
StateSet active_squash = succ & squash;
if (active_squash.any()) {
for (size_t j = active_squash.find_first(); j != active_squash.npos;
j = active_squash.find_next(j)) {
succ &= squash_mask.find(j)->second;
}
}
for (size_t j = succ.find_first(); j != succ.npos; j = succ.find_next(j)) {
const CharReach &cr = cr_by_index[j];
for (size_t s = cr.find_first(); s != cr.npos; s = cr.find_next(s)) {
next[s].set(j); /* already alpha'ed */
}
}
next[alpha[TOP]] = in;
if (top_allowed) {
/* we don't add in the anchored starts as the only case as the only
* time it is appropriate is if no characters have been consumed.*/
next[alpha[TOP]] |= nfa.initDS;
active_squash = next[alpha[TOP]] & squash;
if (active_squash.any()) {
for (size_t j = active_squash.find_first(); j != active_squash.npos;
j = active_squash.find_next(j)) {
next[alpha[TOP]] &= squash_mask.find(j)->second;
}
}
}
}
} // namespace ue2
#endif
|
