vectorscan/src/nfagraph/ng_misc_opt.h
2016-03-01 11:13:23 +11:00

78 lines
2.9 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 Miscellaneous optimisations.
*/
#ifndef NG_MISC_OPT_H
#define NG_MISC_OPT_H
#include <map>
#include <vector>
#include "ng_holder.h"
#include "som/som.h"
#include "util/depth.h"
namespace ue2 {
/** Small structure describing the bounds on a repeat. */
struct BoundedRepeatSummary {
BoundedRepeatSummary(void) : repeatMin(0), repeatMax(depth::infinity()) {}
BoundedRepeatSummary(const depth &min_in, const depth &max_in)
: repeatMin(min_in), repeatMax(max_in) {
assert(repeatMin <= repeatMax);
assert(repeatMax.is_reachable());
}
bool unbounded(void) const { return repeatMax.is_infinite(); }
depth repeatMin; //!< minimum repeat bound.
depth repeatMax; //!< maximum repeat bound.
};
/* returns true if anything changed */
bool improveGraph(NGHolder &g, som_type som);
/** Sometimes the reach of a vertex is greater than it needs to be to reduce
* stop chars for the benefit of the rest of our code base (accel, etc). In
* these circumstances, we can treat the reach as the smaller one as
* the graphs are equivalent. */
CharReach reduced_cr(NFAVertex v, const NGHolder &g,
const std::map<NFAVertex, BoundedRepeatSummary> &br_cyclic);
std::vector<CharReach> reduced_cr(const NGHolder &g,
const std::map<NFAVertex, BoundedRepeatSummary> &br_cyclic);
/** Remove cyclic stars connected to start */
bool mergeCyclicDotStars(NGHolder &g);
} // namespace ue2
#endif