initial integration of opt

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/test/cnf_backbones.cpp

@@ -0,0 +1,218 @@
+/*++
+Copyright (c) 2017 Microsoft Corporation
+
+--*/
+#include<iostream>
+#include<time.h>
+#include<signal.h>
+#include"timeout.h"
+#include"rlimit.h"
+#include"dimacs.h"
+#include"sat_solver.h"
+#include"gparams.h"
+
+static sat::solver * g_solver = 0;
+static clock_t       g_start_time;
+
+static void display_statistics() {
+    clock_t end_time = clock();
+    if (g_solver) {
+        std::cout.flush();
+        std::cerr.flush();
+        
+        statistics st;
+        g_solver->collect_statistics(st);
+        st.update("total time", ((static_cast<double>(end_time) - static_cast<double>(g_start_time)) / CLOCKS_PER_SEC));
+        st.display_smt2(std::cout);
+    }
+}
+
+static void on_timeout() {
+    display_statistics();
+    exit(0);
+}
+
+static void STD_CALL on_ctrl_c(int) {
+    signal (SIGINT, SIG_DFL);
+    display_statistics();
+    raise(SIGINT);
+}
+
+static void display_model(sat::solver const & s) {
+    sat::model const & m = s.get_model();
+    for (unsigned i = 1; i < m.size(); i++) {
+        switch (m[i]) {
+        case l_false: std::cout << "-" << i << " ";  break;
+        case l_undef: break;
+        case l_true: std::cout << i << " ";  break;
+        }
+    }
+    std::cout << "\n";
+}
+
+static void display_status(lbool r) {
+    switch (r) {
+    case l_true: 
+        std::cout << "sat\n"; 
+        break;
+    case l_undef: 
+        std::cout << "unknown\n"; 
+        break;
+    case l_false: 
+        std::cout << "unsat\n"; 
+        break;
+    }
+}
+
+static void prune_unfixed(sat::literal_vector& lambda, sat::model const& m) {
+    for (unsigned i = 0; i < lambda.size(); ++i) {
+        if ((m[lambda[i].var()] == l_false) != lambda[i].sign()) {
+            lambda[i] = lambda.back();
+            lambda.pop_back();
+            --i;
+        }
+    }
+}
+
+// Algorithm 7: Corebased Algorithm with Chunking
+
+static void back_remove(sat::literal_vector& lits, sat::literal l) {
+    for (unsigned i = lits.size(); i > 0; ) {
+        --i;
+        if (lits[i] == l) {
+            lits[i] = lits.back();
+            lits.pop_back();
+            return;
+        }
+    }
+    std::cout << "UNREACHABLE\n";
+}
+
+static void brute_force_consequences(sat::solver& s, sat::literal_vector const& gamma, sat::literal_vector& backbones) {
+    for (unsigned i = 0; i < gamma.size(); ++i) {
+        sat::literal nlit = ~gamma[i];
+        lbool r = s.check(1, &nlit);
+        if (r == l_false) {
+            backbones.push_back(gamma[i]);
+        }
+    }
+}
+
+static lbool core_chunking(sat::solver& s, sat::bool_var_vector& vars, vector<sat::literal_vector>& conseq, unsigned K) {
+    lbool r = s.check();
+    display_status(r);
+    if (r != l_true) {
+        return r;
+    }
+    sat::model const & m = s.get_model();
+    sat::literal_vector lambda, backbones;
+    for (unsigned i = 1; i < m.size(); i++) {
+        lambda.push_back(sat::literal(i, m[i] == l_false));
+    }
+    while (!lambda.empty()) {
+        IF_VERBOSE(1, verbose_stream() << "(sat-backbone-core " << lambda.size() << " " << backbones.size() << ")\n";);
+        unsigned k = std::min(K, lambda.size());
+        sat::literal_vector gamma, omegaN;
+        for (unsigned i = 0; i < k; ++i) {
+            sat::literal l = lambda[lambda.size() - i - 1];
+            gamma.push_back(l);
+            omegaN.push_back(~l);
+        }
+        while (true) {
+            r = s.check(omegaN.size(), omegaN.c_ptr());
+            if (r == l_true) {
+                IF_VERBOSE(1, verbose_stream() << "(sat) " << omegaN << "\n";);
+                prune_unfixed(lambda, s.get_model());
+                break;
+            }
+            sat::literal_vector const& core = s.get_core();
+            sat::literal_vector occurs;
+            IF_VERBOSE(1, verbose_stream() << "(core " << core.size() << ")\n";);
+            for (unsigned i = 0; i < omegaN.size(); ++i) {
+                if (core.contains(omegaN[i])) {
+                    occurs.push_back(omegaN[i]);
+                }
+            }
+            if (occurs.size() == 1) {
+                sat::literal lit = occurs.back();
+                sat::literal nlit = ~lit;
+                backbones.push_back(~lit);
+                back_remove(lambda, ~lit);
+                back_remove(gamma, ~lit);
+                s.mk_clause(1, &nlit);
+            }
+            for (unsigned i = 0; i < omegaN.size(); ++i) {
+                if (occurs.contains(omegaN[i])) {
+                    omegaN[i] = omegaN.back();
+                    omegaN.pop_back();
+                    --i;
+                }
+            }
+            if (omegaN.empty() && occurs.size() > 1) {
+                brute_force_consequences(s, gamma, backbones);
+                for (unsigned i = 0; i < gamma.size(); ++i) {
+                    back_remove(lambda, gamma[i]);
+                }
+                break;
+            }
+        }
+    }
+    for (unsigned i = 0; i < backbones.size(); ++i) {
+        sat::literal_vector cons;
+        cons.push_back(backbones[i]);
+        conseq.push_back(cons);
+    }
+    return l_true;
+}
+
+
+static void cnf_backbones(bool use_chunk, char const* file_name) {
+    g_start_time = clock();
+    register_on_timeout_proc(on_timeout);
+    signal(SIGINT, on_ctrl_c);
+    params_ref p = gparams::get_module("sat");
+    p.set_bool("produce_models", true);
+    reslimit limit;
+    sat::solver solver(p, limit, 0);
+    g_solver = &solver;
+
+    if (file_name) {
+        std::ifstream in(file_name);
+        if (in.bad() || in.fail()) {
+            std::cerr << "(error \"failed to open file '" << file_name << "'\")" << std::endl;
+            exit(ERR_OPEN_FILE);
+        }
+        parse_dimacs(in, solver);
+    }
+    else {
+        parse_dimacs(std::cin, solver);
+    }
+    IF_VERBOSE(20, solver.display_status(verbose_stream()););
+    
+    vector<sat::literal_vector> conseq;
+    sat::bool_var_vector vars;
+    sat::literal_vector assumptions;
+    for (unsigned i = 1; i < solver.num_vars(); ++i) {
+        vars.push_back(i);        
+        solver.set_external(i);
+    }
+    lbool r;
+    if (use_chunk) {
+        r = core_chunking(solver, vars, conseq, 100);
+    }
+    else {
+        r = solver.get_consequences(assumptions, vars, conseq);
+    }
+    std::cout << vars.size() << " " << conseq.size() << "\n";
+    display_status(r);
+    display_statistics();
+}
+
+void tst_cnf_backbones(char ** argv, int argc, int& i) {
+    if (i + 1 < argc) {
+        bool use_chunk = (i + 2 < argc && argv[i + 2] == std::string("chunk"));
+        cnf_backbones(use_chunk, argv[i + 1]);
+        ++i;
+        if (use_chunk) ++i;
+    }
+}

src/test/ddnf.cpp

@@ -1,4 +1,3 @@
-
 /*++
 Copyright (c) 2015 Microsoft Corporation
 

src/test/main.cpp

@@ -243,8 +243,12 @@ int main(int argc, char ** argv) {
     TST(model_evaluator);
     TST(get_consequences);
     TST(pb2bv);
+<<<<<<< HEAD
     TST_ARGV(sat_lookahead);
     TST_ARGV(sat_local_search);
+=======
+    TST_ARGV(cnf_backbones);
+>>>>>>> 69aa5ca877f5de0a2c00515d0fe86a797b95701a
     //TST_ARGV(hs);
 }