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GCC Code Coverage Report

Directory:	.		Exec	Total	Coverage
File:	src/theory/arith/dual_simplex.h	Lines:	8	8	100.0 %
Date:	2021-11-07	Branches:	0	0	0.0 %


/******************************************************************************
 * Top contributors (to current version):
 *   Tim King, Mathias Preiner, Morgan Deters
 *
 * This file is part of the cvc5 project.
 *
 * Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
 * in the top-level source directory and their institutional affiliations.
 * All rights reserved.  See the file COPYING in the top-level source
 * directory for licensing information.
 * ****************************************************************************
 *
 * This is an implementation of the Simplex Module for the Simplex for
 * DPLL(T) decision procedure.
 *
 * This implements the Simplex module for the Simpelx for DPLL(T) decision
 * procedure.
 * See the Simplex for DPLL(T) technical report for more background.(citation?)
 * This shares with the theory a Tableau, and a PartialModel that:
 *  - satisfies the equalities in the Tableau, and
 *  - the assignment for the non-basic variables satisfies their bounds.
 * This is required to either produce a conflict or satisifying PartialModel.
 * Further, we require being told when a basic variable updates its value.
 *
 * During the Simplex search we maintain a queue of variables.
 * The queue is required to contain all of the basic variables that voilate
 * their bounds.
 * As elimination from the queue is more efficient to be done lazily,
 * we do not maintain that the queue of variables needs to be only basic
 * variables or only variables that satisfy their bounds.
 *
 * The simplex procedure roughly follows Alberto's thesis. (citation?)
 * There is one round of selecting using a heuristic pivoting rule.
 * (See PreferenceFunction Documentation for the available options.)
 * The non-basic variable is the one that appears in the fewest pivots.
 * (Bruno says that Leonardo invented this first.)
 * After this, Bland's pivot rule is invoked.
 *
 * During this proccess, we periodically inspect the queue of variables to
 * 1) remove now extraneous extries,
 * 2) detect conflicts that are "waiting" on the queue but may not be detected
 *    by the current queue heuristics, and
 * 3) detect multiple conflicts.
 *
 * Conflicts are greedily slackened to use the weakest bounds that still
 * produce the conflict.
 *
 * Extra things tracked atm: (Subject to change at Tim's whims)
 * - A superset of all of the newly pivoted variables.
 * - A queue of additional conflicts that were discovered by Simplex.
 *   These are theory valid and are currently turned into lemmas
 */

#include "cvc5_private.h"

#pragma once

#include "theory/arith/simplex.h"
#include "util/statistics_stats.h"

namespace cvc5 {
namespace theory {
namespace arith {

class DualSimplexDecisionProcedure : public SimplexDecisionProcedure{
public:
 DualSimplexDecisionProcedure(Env& env,
                              LinearEqualityModule& linEq,
                              ErrorSet& errors,
                              RaiseConflict conflictChannel,
                              TempVarMalloc tvmalloc);

 Result::Sat findModel(bool exactResult) override
 {
   return dualFindModel(exactResult);
  }

private:

  /**
   * Maps a variable to how many times they have been used as a pivot in the
   * simplex search.
   */
  DenseMultiset d_pivotsInRound;

  Result::Sat dualFindModel(bool exactResult);

  /**
   * This is the main simplex for DPLL(T) loop.
   * It runs for at most maxIterations.
   *
   * Returns true iff it has found a conflict.
   * d_conflictVariable will be set and the conflict for this row is reported.
   */
  bool searchForFeasibleSolution(uint32_t maxIterations);


  bool processSignals(){
    TimerStat &timer = d_statistics.d_processSignalsTime;
    IntStat& conflictStat  = d_statistics.d_recentViolationCatches;
    return standardProcessSignals(timer, conflictStat);
  }
  /** These fields are designed to be accessible to TheoryArith methods. */
  class Statistics {
  public:
    IntStat d_statUpdateConflicts;
    TimerStat d_processSignalsTime;
    IntStat d_simplexConflicts;
    IntStat d_recentViolationCatches;
    TimerStat d_searchTime;

    ReferenceStat<uint32_t> d_finalCheckPivotCounter;

    Statistics(uint32_t& pivots);
  } d_statistics;
};/* class DualSimplexDecisionProcedure */

}  // namespace arith
}  // namespace theory
}  // namespace cvc5


Generated by: GCOVR (Version 3.2)

Line	Exec	Source
1		/******************************************************************************
2		* Top contributors (to current version):
3		* Tim King, Mathias Preiner, Morgan Deters
4		*
5		* This file is part of the cvc5 project.
6		*
7		* Copyright (c) 2009-2021 by the authors listed in the file AUTHORS
8		* in the top-level source directory and their institutional affiliations.
9		* All rights reserved. See the file COPYING in the top-level source
10		* directory for licensing information.
11		* ****************************************************************************
12		*
13		* This is an implementation of the Simplex Module for the Simplex for
14		* DPLL(T) decision procedure.
15		*
16		* This implements the Simplex module for the Simpelx for DPLL(T) decision
17		* procedure.
18		* See the Simplex for DPLL(T) technical report for more background.(citation?)
19		* This shares with the theory a Tableau, and a PartialModel that:
20		* - satisfies the equalities in the Tableau, and
21		* - the assignment for the non-basic variables satisfies their bounds.
22		* This is required to either produce a conflict or satisifying PartialModel.
23		* Further, we require being told when a basic variable updates its value.
24		*
25		* During the Simplex search we maintain a queue of variables.
26		* The queue is required to contain all of the basic variables that voilate
27		* their bounds.
28		* As elimination from the queue is more efficient to be done lazily,
29		* we do not maintain that the queue of variables needs to be only basic
30		* variables or only variables that satisfy their bounds.
31		*
32		* The simplex procedure roughly follows Alberto's thesis. (citation?)
33		* There is one round of selecting using a heuristic pivoting rule.
34		* (See PreferenceFunction Documentation for the available options.)
35		* The non-basic variable is the one that appears in the fewest pivots.
36		* (Bruno says that Leonardo invented this first.)
37		* After this, Bland's pivot rule is invoked.
38		*
39		* During this proccess, we periodically inspect the queue of variables to
40		* 1) remove now extraneous extries,
41		* 2) detect conflicts that are "waiting" on the queue but may not be detected
42		* by the current queue heuristics, and
43		* 3) detect multiple conflicts.
44		*
45		* Conflicts are greedily slackened to use the weakest bounds that still
46		* produce the conflict.
47		*
48		* Extra things tracked atm: (Subject to change at Tim's whims)
49		* - A superset of all of the newly pivoted variables.
50		* - A queue of additional conflicts that were discovered by Simplex.
51		* These are theory valid and are currently turned into lemmas
52		*/
53
54		#include "cvc5_private.h"
55
56		#pragma once
57
58		#include "theory/arith/simplex.h"
59		#include "util/statistics_stats.h"
60
61		namespace cvc5 {
62		namespace theory {
63		namespace arith {
64
65	15268	class DualSimplexDecisionProcedure : public SimplexDecisionProcedure{
66		public:
67		DualSimplexDecisionProcedure(Env& env,
68		LinearEqualityModule& linEq,
69		ErrorSet& errors,
70		RaiseConflict conflictChannel,
71		TempVarMalloc tvmalloc);
72
73	2416045	Result::Sat findModel(bool exactResult) override
74		{
75	2416045	return dualFindModel(exactResult);
76		}
77
78		private:
79
80		/**
81		* Maps a variable to how many times they have been used as a pivot in the
82		* simplex search.
83		*/
84		DenseMultiset d_pivotsInRound;
85
86		Result::Sat dualFindModel(bool exactResult);
87
88		/**
89		* This is the main simplex for DPLL(T) loop.
90		* It runs for at most maxIterations.
91		*
92		* Returns true iff it has found a conflict.
93		* d_conflictVariable will be set and the conflict for this row is reported.
94		*/
95		bool searchForFeasibleSolution(uint32_t maxIterations);
96
97
98	1296723	bool processSignals(){
99	1296723	TimerStat &timer = d_statistics.d_processSignalsTime;
100	1296723	IntStat& conflictStat = d_statistics.d_recentViolationCatches;
101	1296723	return standardProcessSignals(timer, conflictStat);
102		}
103		/** These fields are designed to be accessible to TheoryArith methods. */
104	15268	class Statistics {
105		public:
106		IntStat d_statUpdateConflicts;
107		TimerStat d_processSignalsTime;
108		IntStat d_simplexConflicts;
109		IntStat d_recentViolationCatches;
110		TimerStat d_searchTime;
111
112		ReferenceStat<uint32_t> d_finalCheckPivotCounter;
113
114		Statistics(uint32_t& pivots);
115		} d_statistics;
116		};/* class DualSimplexDecisionProcedure */
117
118		} // namespace arith
119		} // namespace theory
120		} // namespace cvc5