Examples with Node kodkod.ast.Node used on opensource projects

Example 1 with Node

use of kodkod.ast.Node in project org.alloytools.alloy by AlloyTools.

the class Translator method inlinePredicates.

/**
 * Returns an annotated formula f such that f.node is equivalent to
 * annotated.node with its <tt>simplified</tt> predicates replaced with their
 * corresponding Formulas and the remaining predicates replaced with equivalent
 * constraints. The annotated formula f will contain transitive source
 * information for each of the subformulas of f.node. Specifically, let t be a
 * subformula of f.node, and s be a descdendent of annotated.node from which t
 * was derived. Then, f.source[t] = annotated.source[s].
 * </p>
 *
 * @requires simplified.keySet() in
 *           annotated.predicates()[RelationPredicate.NAME]
 * @requires no disj p, p': simplified.keySet() | simplified.get(p) =
 *           simplifed.get(p') // this must hold in order to maintain the
 *           invariant that each subformula of the returned formula has exactly
 *           one source
 * @requires for each p in simplified.keySet(), the formulas "p and
 *           [[this.bounds]]" and "simplified.get(p) and [[this.bounds]]" are
 *           equisatisfiable
 * @return an annotated formula f such that f.node is equivalent to
 *         annotated.node with its <tt>simplified</tt> predicates replaced with
 *         their corresponding Formulas and the remaining predicates replaced
 *         with equivalent constraints.
 */
private AnnotatedNode<Formula> inlinePredicates(final AnnotatedNode<Formula> annotated, final Map<RelationPredicate, Formula> simplified) {
    final Map<Node, Node> sources = new IdentityHashMap<Node, Node>();
    final AbstractReplacer inliner = new AbstractReplacer(annotated.sharedNodes()) {

        private RelationPredicate source = null;

        @Override
        protected <N extends Node> N cache(N node, N replacement) {
            if (replacement instanceof Formula) {
                if (source == null) {
                    final Node nsource = annotated.sourceOf(node);
                    if (replacement != nsource)
                        sources.put(replacement, nsource);
                } else {
                    sources.put(replacement, source);
                }
            }
            return super.cache(node, replacement);
        }

        @Override
        public Formula visit(RelationPredicate pred) {
            Formula ret = lookup(pred);
            if (ret != null)
                return ret;
            source = pred;
            if (simplified.containsKey(pred)) {
                ret = simplified.get(pred).accept(this);
            } else {
                ret = pred.toConstraints().accept(this);
            }
            source = null;
            return cache(pred, ret);
        }
    };
    return annotate(annotated.node().accept(inliner), sources);
}

Example 2 with Node

use of kodkod.ast.Node in project org.alloytools.alloy by AlloyTools.

the class Nodes method allRoots.

/**
 * Returns all {@linkplain #roots(Formula) roots} of the given formula such that
 * a node in the given collection is reachable from that root.
 *
 * @return { r: roots(formula) | some r.*components & descendants.elements }
 */
@SuppressWarnings("unchecked")
public static Set<Formula> allRoots(Formula formula, Collection<? extends Node> descendants) {
    final Set<Node> desc = new IdentityHashSet<Node>(descendants);
    final AbstractDetector detector = new AbstractDetector(Collections.EMPTY_SET) {

        @Override
        protected Boolean lookup(Node n) {
            return desc.contains(n) ? Boolean.TRUE : cache.get(n);
        }

        @Override
        protected Boolean cache(Node n, boolean val) {
            final Boolean ret = Boolean.valueOf(val);
            cache.put(n, ret);
            return ret;
        }
    };
    final Set<Formula> roots = new LinkedHashSet<Formula>();
    for (Formula root : roots(formula)) {
        if (root.accept(detector)) {
            roots.add(root);
        }
    }
    return roots;
}

Example 3 with Node

use of kodkod.ast.Node in project org.alloytools.alloy by AlloyTools.

the class StrategyUtils method roots.

/**
 * Returns a map from variables to the corresponding roots of log.formula.
 *
 * @return
 *
 *         <pre>
 *
 * { v: int, f: Formula | some r: log.records |
 *   r.translated in log.roots() and
 *   r.translated = f and
 *   r.env.isEmpty() and
 *   abs(r.literal) != Integer.MAX_VALUE and
 *   v = abs(r.literal) and
 *   no r': log.records | r'.node = r.node && log.replay.r' > log.replay.r }
 *         </pre>
 */
static SparseSequence<Formula> roots(TranslationLog log) {
    final SparseSequence<Formula> rootVars = new TreeSequence<Formula>();
    final Set<Formula> roots = log.roots();
    final Map<Formula, int[]> maxRootVar = new IdentityHashMap<Formula, int[]>(roots.size());
    final RecordFilter filter = new RecordFilter() {

        @Override
        public boolean accept(Node node, Formula translated, int literal, Map<Variable, TupleSet> env) {
            return roots.contains(translated) && env.isEmpty();
        }
    };
    for (Iterator<TranslationRecord> itr = log.replay(filter); itr.hasNext(); ) {
        TranslationRecord record = itr.next();
        int[] var = maxRootVar.get(record.translated());
        if (var == null) {
            var = new int[1];
            maxRootVar.put(record.translated(), var);
        }
        var[0] = StrictMath.abs(record.literal());
    }
    for (Map.Entry<Formula, int[]> entry : maxRootVar.entrySet()) {
        final int topVar = entry.getValue()[0];
        if (// formula simplified to TRUE
        topVar != Integer.MAX_VALUE)
            rootVars.put(topVar, entry.getKey());
    }
    return rootVars;
}

Example 4 with Node

use of kodkod.ast.Node in project org.alloytools.alloy by AlloyTools.

the class StrategyUtils method rootVars.

/**
 * Returns the variables that correspond to the roots of log.formula.
 *
 * @return
 *
 *         <pre>
 *
 * { v: int | some r: log.records |
 *   r.node in log.roots() and
 *   r.env.isEmpty() and
 *   abs(r.literal) != Integer.MAX_VALUE and
 *   v = abs(r.literal) and
 *   no r': log.records | r'.node = r.node && log.replay.r' > log.replay.r }
 *         </pre>
 */
public static IntSet rootVars(TranslationLog log) {
    final IntSet rootVars = new IntTreeSet();
    final Set<Formula> roots = log.roots();
    final Map<Formula, int[]> maxRootVar = new LinkedHashMap<Formula, int[]>(roots.size());
    final RecordFilter filter = new RecordFilter() {

        @Override
        public boolean accept(Node node, Formula translated, int literal, Map<Variable, TupleSet> env) {
            return roots.contains(translated) && env.isEmpty();
        }
    };
    for (Iterator<TranslationRecord> itr = log.replay(filter); itr.hasNext(); ) {
        TranslationRecord record = itr.next();
        int[] var = maxRootVar.get(record.translated());
        if (var == null) {
            var = new int[1];
            maxRootVar.put(record.translated(), var);
        }
        var[0] = StrictMath.abs(record.literal());
    }
    for (int[] var : maxRootVar.values()) {
        int topVar = var[0];
        if (// formula simplified to TRUE
        topVar != Integer.MAX_VALUE)
            rootVars.add(var[0]);
    }
    return rootVars;
}

Example 5 with Node

use of kodkod.ast.Node in project org.alloytools.alloy by AlloyTools.

the class A4Solution method solve.

// ===================================================================================================//
/**
 * Solve for the solution if not solved already; if cmd==null, we will simply
 * use the lowerbound of each relation as its value.
 */
A4Solution solve(final A4Reporter rep, Command cmd, Simplifier simp, boolean tryBookExamples) throws Err, IOException {
    // If already solved, then return this object as is
    if (solved)
        return this;
    // the lower bound of each relation
    if (cmd == null) {
        Instance inst = new Instance(bounds.universe());
        for (int max = max(), i = min(); i <= max; i++) {
            Tuple it = factory.tuple("" + i);
            inst.add(i, factory.range(it, it));
        }
        for (Relation r : bounds.relations()) inst.add(r, bounds.lowerBound(r));
        eval = new Evaluator(inst, solver.options());
        rename(this, null, null, new UniqueNameGenerator());
        solved();
        return this;
    }
    // Otherwise, prepare to do the solve...
    final A4Options opt = originalOptions;
    long time = System.currentTimeMillis();
    rep.debug("Simplifying the bounds...\n");
    if (opt.inferPartialInstance && simp != null && formulas.size() > 0 && !simp.simplify(rep, this, formulas))
        addFormula(Formula.FALSE, Pos.UNKNOWN);
    rep.translate(opt.solver.id(), bitwidth, maxseq, solver.options().skolemDepth(), solver.options().symmetryBreaking());
    Formula fgoal = Formula.and(formulas);
    rep.debug("Generating the solution...\n");
    kEnumerator = null;
    Solution sol = null;
    final Reporter oldReporter = solver.options().reporter();
    final boolean[] solved = new boolean[] { true };
    solver.options().setReporter(new // Set up a
    AbstractReporter() {

        // reporter to
        // catch the
        // type+pos of
        // skolems
        @Override
        public void skolemizing(Decl decl, Relation skolem, List<Decl> predecl) {
            try {
                Type t = kv2typepos(decl.variable()).a;
                if (t == Type.EMPTY)
                    return;
                for (int i = (predecl == null ? -1 : predecl.size() - 1); i >= 0; i--) {
                    Type pp = kv2typepos(predecl.get(i).variable()).a;
                    if (pp == Type.EMPTY)
                        return;
                    t = pp.product(t);
                }
                kr2type(skolem, t);
            }// Exception here is not fatal
             catch (Throwable ex) {
            }
        }

        @Override
        public void solvingCNF(int primaryVars, int vars, int clauses) {
            if (solved[0])
                return;
            else
                // initially solved[0] is true, so we
                solved[0] = true;
            // won't report the # of vars/clauses
            if (rep != null)
                rep.solve(primaryVars, vars, clauses);
        }
    });
    if (!opt.solver.equals(SatSolver.CNF) && !opt.solver.equals(SatSolver.KK) && tryBookExamples) {
        // try
        // book
        // examples
        A4Reporter r = AlloyCore.isDebug() ? rep : null;
        try {
            sol = BookExamples.trial(r, this, fgoal, solver, cmd.check);
        } catch (Throwable ex) {
            sol = null;
        }
    }
    // this allows the reporter to report the # of
    solved[0] = false;
    // vars/clauses
    for (Relation r : bounds.relations()) {
        formulas.add(r.eq(r));
    }
    // Without this, kodkod refuses to grow unmentioned relations
    fgoal = Formula.and(formulas);
    // Now pick the solver and solve it!
    if (opt.solver.equals(SatSolver.KK)) {
        File tmpCNF = File.createTempFile("tmp", ".java", new File(opt.tempDirectory));
        String out = tmpCNF.getAbsolutePath();
        Util.writeAll(out, debugExtractKInput());
        rep.resultCNF(out);
        return null;
    }
    if (opt.solver.equals(SatSolver.CNF)) {
        File tmpCNF = File.createTempFile("tmp", ".cnf", new File(opt.tempDirectory));
        String out = tmpCNF.getAbsolutePath();
        solver.options().setSolver(WriteCNF.factory(out));
        try {
            sol = solver.solve(fgoal, bounds);
        } catch (WriteCNF.WriteCNFCompleted ex) {
            rep.resultCNF(out);
            return null;
        }
        // The formula is trivial (otherwise, it would have thrown an
        // exception)
        // Since the user wants it in CNF format, we manually generate a
        // trivially satisfiable (or unsatisfiable) CNF file.
        Util.writeAll(out, sol.instance() != null ? "p cnf 1 1\n1 0\n" : "p cnf 1 2\n1 0\n-1 0\n");
        rep.resultCNF(out);
        return null;
    }
    if (!solver.options().solver().incremental()) /*
                                                      * || solver.options().solver()==SATFactory. ZChaffMincost
                                                      */
    {
        if (sol == null)
            sol = solver.solve(fgoal, bounds);
    } else {
        kEnumerator = new Peeker<Solution>(solver.solveAll(fgoal, bounds));
        if (sol == null)
            sol = kEnumerator.next();
    }
    if (!solved[0])
        rep.solve(0, 0, 0);
    final Instance inst = sol.instance();
    // To ensure no more output during SolutionEnumeration
    solver.options().setReporter(oldReporter);
    // If unsatisfiable, then retreive the unsat core if desired
    if (inst == null && solver.options().solver() == SATFactory.MiniSatProver) {
        try {
            lCore = new LinkedHashSet<Node>();
            Proof p = sol.proof();
            if (sol.outcome() == UNSATISFIABLE) {
                // only perform the minimization if it was UNSATISFIABLE,
                // rather than TRIVIALLY_UNSATISFIABLE
                int i = p.highLevelCore().size();
                rep.minimizing(cmd, i);
                if (opt.coreMinimization == 0)
                    try {
                        p.minimize(new RCEStrategy(p.log()));
                    } catch (Throwable ex) {
                    }
                if (opt.coreMinimization == 1)
                    try {
                        p.minimize(new HybridStrategy(p.log()));
                    } catch (Throwable ex) {
                    }
                rep.minimized(cmd, i, p.highLevelCore().size());
            }
            for (Iterator<TranslationRecord> it = p.core(); it.hasNext(); ) {
                Object n = it.next().node();
                if (n instanceof Formula)
                    lCore.add((Formula) n);
            }
            Map<Formula, Node> map = p.highLevelCore();
            hCore = new LinkedHashSet<Node>(map.keySet());
            hCore.addAll(map.values());
        } catch (Throwable ex) {
            lCore = hCore = null;
        }
    }
    // If satisfiable, then add/rename the atoms and skolems
    if (inst != null) {
        eval = new Evaluator(inst, solver.options());
        rename(this, null, null, new UniqueNameGenerator());
    }
    // report the result
    solved();
    time = System.currentTimeMillis() - time;
    if (inst != null)
        rep.resultSAT(cmd, time, this);
    else
        rep.resultUNSAT(cmd, time, this);
    return this;
}