vectorscan/src/nfagraph/ng_limex.h
2015-10-20 09:13:35 +11:00

139 lines
5.1 KiB
C++

/*
* Copyright (c) 2015, 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 Limex NFA construction code.
*/
#ifndef NG_LIMEX_H
#define NG_LIMEX_H
#include "ue2common.h"
#include "som/som.h"
#include "util/alloc.h"
#include <map>
#include <memory>
#include <vector>
struct NFA;
namespace ue2 {
class CharReach;
class NG;
class NGHolder;
class ReportManager;
struct CompileContext;
/** \brief Determine if the given graph is implementable as an NFA.
*
* Returns zero if the NFA is not implementable (usually because it has too
* many states for any of our models). Otherwise returns the number of states.
*
* ReportManager is used by NFA_SUFFIX and NFA_OUTFIX only. NFA_PREFIX and
* NFA_INFIX use unmanaged rose-local reports.
*/
u32 isImplementableNFA(const NGHolder &g, const ReportManager *rm,
const CompileContext &cc);
/** \brief Late-stage graph reductions.
*
* This will call \ref removeRedundancy and apply its changes to the given
* holder only if it is implementable afterwards. */
void reduceImplementableGraph(NGHolder &g, som_type som, const ReportManager *rm,
const CompileContext &cc);
/**
* \brief For a given graph, count the number of accel states it will have in
* an implementation.
*
* \return the number of accel states, or NFA_MAX_ACCEL_STATES + 1 if an
* implementation would not be constructible.
*/
u32 countAccelStates(const NGHolder &g, const ReportManager *rm,
const CompileContext &cc);
/** \brief Construct an NFA from the given NFAGraph.
*
* Returns zero if the NFA is not implementable (usually because it has too
* many states for any of our models). Otherwise returns the number of states.
*
* ReportManager is used by NFA_SUFFIX and NFA_OUTFIX only. NFA_PREFIX and
* NFA_INFIX use unmanaged rose-local reports.
*
* Note: this variant of the function allows a model to be specified with the
* \a hint parameter.
*/
aligned_unique_ptr<NFA>
constructNFA(const NGHolder &g, const ReportManager *rm,
const std::map<u32, u32> &fixed_depth_tops,
const std::map<u32, std::vector<std::vector<CharReach>>> &triggers,
bool compress_state, const CompileContext &cc);
/** \brief Build a reverse NFA from the graph given, which should have already
* been reversed.
*
* Used for reverse NFAs used in SOM mode.
*/
aligned_unique_ptr<NFA> constructReversedNFA(const NGHolder &h,
const CompileContext &cc);
#ifndef RELEASE_BUILD
/** \brief Construct an NFA (with model type hint) from the given NFAGraph.
*
* Returns zero if the NFA is not implementable (usually because it has too
* many states for any of our models). Otherwise returns the number of states.
*
* ReportManager is used by NFA_SUFFIX and NFA_OUTFIX only. NFA_PREFIX and
* NFA_INFIX use unmanaged rose-local reports.
*
* Note: this variant of the function allows a model to be specified with the
* \a hint parameter.
*/
aligned_unique_ptr<NFA>
constructNFA(const NGHolder &g, const ReportManager *rm,
const std::map<u32, u32> &fixed_depth_tops,
const std::map<u32, std::vector<std::vector<CharReach>>> &triggers,
bool compress_state, u32 hint, const CompileContext &cc);
/** \brief Build a reverse NFA (with model type hint) from the graph given,
* which should have already been reversed.
*
* Used for reverse NFAs used in SOM mode.
*/
aligned_unique_ptr<NFA> constructReversedNFA(const NGHolder &h, u32 hint,
const CompileContext &cc);
#endif // RELEASE_BUILD
} // namespace ue2
#endif // NG_METEOR_H