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https://github.com/Z3Prover/z3
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debugging var_eqs
This commit is contained in:
parent
09152013b3
commit
7a3a696b6f
3 changed files with 179 additions and 176 deletions
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@ -34,9 +34,11 @@ bool try_insert(const A& elem, B& collection) {
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collection.insert(elem);
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return true;
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}
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typedef lp::constraint_index lpci;
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typedef lp::lconstraint_kind llc;
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struct point {
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rational x;
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rational y;
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@ -86,7 +88,7 @@ struct solver::imp {
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};
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//fields
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var_eqs m_vars_equivalence;
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var_eqs m_evars;
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vector<monomial> m_monomials;
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rooted_mon_table m_rm_table;
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@ -114,7 +116,7 @@ struct solver::imp {
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imp(lp::lar_solver& s, reslimit& lim, params_ref const& p)
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:
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m_vars_equivalence(),
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m_evars(),
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m_lar_solver(s)
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// m_limit(lim),
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// m_params(p)
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@ -201,7 +203,7 @@ struct solver::imp {
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}
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rational canonize_sign_of_var(lpvar j) const {
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return m_vars_equivalence.find_sign(j);
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return m_evars.find(j).rsign();
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}
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// the value of the rooted monomias is equal to the value of the variable multiplied
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@ -222,6 +224,7 @@ struct solver::imp {
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void push() {
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TRACE("nla_solver",);
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m_monomials_counts.push_back(m_monomials.size());
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m_evars.push();
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}
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void deregister_monomial_from_rooted_monomials (const monomial & m, unsigned i){
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@ -247,7 +250,8 @@ struct solver::imp {
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deregister_monomial_from_tables(m_monomials[i], i);
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}
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m_monomials.shrink(new_size);
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m_monomials_counts.shrink(m_monomials_counts.size() - n);
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m_monomials_counts.shrink(m_monomials_counts.size() - n);
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m_evars.pop(n);
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}
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rational mon_value_by_vars(unsigned i) const {
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@ -287,7 +291,7 @@ struct solver::imp {
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}
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void explain(lpvar j, lp::explanation& exp) const {
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m_vars_equivalence.explain(j, exp);
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m_evars.explain(j, exp);
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}
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template <typename T>
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@ -616,17 +620,17 @@ struct solver::imp {
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//
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svector<lpvar> reduce_monomial_to_rooted(const svector<lpvar> & vars, rational & sign) const {
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svector<lpvar> ret;
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sign = 1;
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bool s = false;
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for (lpvar v : vars) {
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unsigned root = m_vars_equivalence.find(v, sign);
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SASSERT(m_vars_equivalence.is_root(root));
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auto root = m_evars.find(v);
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s ^= root.sign();
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TRACE("nla_solver_eq",
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print_var(v,tout);
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tout << " mapped to ";
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print_var(root, tout););
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ret.push_back(root);
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print_var(root.var(), tout););
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ret.push_back(root.var());
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}
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sign = rational(s? -1: 1);
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std::sort(ret.begin(), ret.end());
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return ret;
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}
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@ -844,10 +848,10 @@ struct solver::imp {
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/*
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unsigned_vector eq_vars(lpvar j) const {
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TRACE("nla_solver_eq", tout << "j = "; print_var(j, tout); tout << "eqs = ";
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for(auto jj : m_vars_equivalence.eq_vars(j)) {
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for(auto jj : m_evars.eq_vars(j)) {
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print_var(jj, tout);
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});
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return m_vars_equivalence.eq_vars(j);
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return m_evars.eq_vars(j);
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}
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*/
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// Monomials m and n vars have the same values, up to "sign"
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@ -1091,7 +1095,7 @@ struct solver::imp {
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if (!(var_has_positive_lower_bound(j) || var_has_negative_upper_bound(j))) {
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return 0;
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}
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sign *= m_vars_equivalence.find_sign(j);
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sign *= m_evars.find(j).rsign();
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}
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return rat_sign(sign);
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}
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@ -1339,13 +1343,13 @@ struct solver::imp {
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bool vars_are_equiv(lpvar a, lpvar b) const {
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SASSERT(abs(vvr(a)) == abs(vvr(b)));
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return m_vars_equivalence.vars_are_equiv(a, b);
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return m_evars.vars_are_equiv(a, b);
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}
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void explain_equiv_vars(lpvar a, lpvar b) {
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SASSERT(abs(vvr(a)) == abs(vvr(b)));
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if (m_vars_equivalence.vars_are_equiv(a, b)) {
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if (m_evars.vars_are_equiv(a, b)) {
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explain(a, current_expl());
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explain(b, current_expl());
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} else {
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@ -1864,9 +1868,9 @@ struct solver::imp {
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auto c2 = m_lar_solver.get_column_upper_bound_witness(v[k]);
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auto c3 = m_lar_solver.get_column_lower_bound_witness(v[k]);
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if (vvr(head) == vvr(v[k]))
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m_vars_equivalence.merge_plus(head, v[k], eq_justification({c0, c1, c2, c3}));
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m_evars.merge_plus(head, v[k], eq_justification({c0, c1, c2, c3}));
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else
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m_vars_equivalence.merge_minus(head, v[k], eq_justification({c0, c1, c2, c3}));
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m_evars.merge_minus(head, v[k], eq_justification({c0, c1, c2, c3}));
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}
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}
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}
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@ -1895,16 +1899,16 @@ struct solver::imp {
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SASSERT(j != static_cast<unsigned>(-1));
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bool sign = (seen_minus && seen_plus)? false : true;
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if (sign)
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m_vars_equivalence.merge_minus(i, j, eq_justification({c0, c1}));
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m_evars.merge_minus(i, j, eq_justification({c0, c1}));
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else
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m_vars_equivalence.merge_plus(i, j, eq_justification({c0, c1}));
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m_evars.merge_plus(i, j, eq_justification({c0, c1}));
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}
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// x is equivalent to y if x = +- y
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void init_vars_equivalence() {
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/* SASSERT(m_vars_equivalence.empty());*/
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/* SASSERT(m_evars.empty());*/
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collect_equivs();
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/* TRACE("nla_solver_details", tout << "number of equivs = " << m_vars_equivalence.size(););*/
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/* TRACE("nla_solver_details", tout << "number of equivs = " << m_evars.size(););*/
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SASSERT((settings().random_next() % 100) || tables_are_ok());
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}
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@ -1932,7 +1936,7 @@ struct solver::imp {
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bool rm_table_is_ok() const {
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for (const auto & rm : m_rm_table.rms()) {
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for (lpvar j : rm.vars()) {
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if (!m_vars_equivalence.is_root(j)){
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if (!m_evars.is_root(j)){
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TRACE("nla_solver", print_var(j, tout););
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return false;
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}
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@ -1945,7 +1949,7 @@ struct solver::imp {
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return vars_table_is_ok() && rm_table_is_ok();
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}
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bool var_is_a_root(lpvar j) const { return m_vars_equivalence.is_root(j); }
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bool var_is_a_root(lpvar j) const { return m_evars.is_root(j); }
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template <typename T>
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bool vars_are_roots(const T& v) const {
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@ -2244,7 +2248,7 @@ struct solver::imp {
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SASSERT(abs(vvr(i)) == abs(vvr(c)));
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auto it = m_var_to_its_monomial.find(i);
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if (it == m_var_to_its_monomial.end()) {
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i = m_vars_equivalence.find(i);
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i = m_evars.find(i).var();
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if (try_insert(i, found_vars)) {
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r.push_back(factor(i, factor_type::VAR));
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}
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@ -2382,7 +2386,7 @@ struct solver::imp {
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void order_lemma_on_factor_binomial_explore(const monomial& m, unsigned k) {
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SASSERT(m.size() == 2);
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lpvar c = m[k];
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lpvar d = m_vars_equivalence.find(c);
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lpvar d = m_evars.find(c).var();
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auto it = m_rm_table.var_map().find(d);
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SASSERT(it != m_rm_table.var_map().end());
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for (unsigned bd_i : it->second) {
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@ -2393,7 +2397,7 @@ struct solver::imp {
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}
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void order_lemma_on_factor_binomial_rm(const monomial& ac, unsigned k, const rooted_mon& rm_bd) {
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factor d(m_vars_equivalence.find(ac[k]), factor_type::VAR);
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factor d(m_evars.find(ac[k]).var(), factor_type::VAR);
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factor b;
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if (!divide(rm_bd, d, b))
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return;
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@ -2407,7 +2411,7 @@ struct solver::imp {
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int p = (k + 1) % 2;
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lpvar a = ac[p];
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lpvar c = ac[k];
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SASSERT(m_vars_equivalence.find(c) == d);
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SASSERT(m_evars.find(c).var() == d);
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rational acv = vvr(ac);
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rational av = vvr(a);
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rational c_sign = rrat_sign(vvr(c));
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@ -20,7 +20,6 @@
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#include "util/lp/var_eqs.h"
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namespace nla {
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@ -40,13 +39,13 @@ namespace nla {
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m_eqs[(~sv.first).index()].pop_back();
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m_eqs[(~sv.second).index()].pop_back();
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}
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m_trail_lim.shrink(n);
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m_trail_lim.shrink(m_trail_lim.size() - n);
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m_trail.shrink(old_sz);
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m_ufctx.get_trail_stack().pop_scope(n);
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}
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void var_eqs::merge(signed_var v1, signed_var v2, eq_justification const& j) {
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unsigned max_i = std::max(v1.index(), v2.index()) + 1;
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unsigned max_i = std::max(v1.index(), v2.index()) + 2;
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m_eqs.reserve(max_i);
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while (m_uf.get_num_vars() <= max_i) m_uf.mk_var();
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m_uf.merge(v1.index(), v2.index());
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@ -62,7 +61,7 @@ namespace nla {
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return v;
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}
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unsigned idx = m_uf.find(v.index());
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return signed_var(idx);
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return signed_var(idx, from_index()); // 0 is needed to call the right constructor
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}
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void var_eqs::explain(signed_var v1, signed_var v2, lp::explanation& e) const {
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@ -85,7 +84,7 @@ namespace nla {
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auto const& next = m_eqs[v.index()];
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unsigned sz = next.size();
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bool seen_all = true;
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for (unsigned i = f.m_index; !seen_all && i < sz; ++i) {
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for (unsigned i = f.m_index; seen_all && i < sz; ++i) {
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justified_var const& jv = next[i];
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if (!m_marked[jv.m_var.index()]) {
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seen_all = false;
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@ -104,6 +103,7 @@ namespace nla {
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for (eq_justification const& j : m_dfs_trail) {
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j.explain(e);
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}
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m_todo.reset();
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m_dfs_trail.reset();
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for (unsigned idx : m_marked_trail) {
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m_marked[idx] = false;
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@ -26,157 +26,156 @@
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namespace nla {
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typedef lp::var_index lpvar;
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typedef lp::constraint_index lpcindex;
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typedef lp::constraint_index lpci;
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struct from_index{};
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class signed_var {
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unsigned m_sv;
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public:
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// constructor, sign = true means minus
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signed_var(lpvar v, bool sign): m_sv((v << 1) + (sign ? 1 : 0)) {}
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// constructor
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explicit signed_var(unsigned sv): m_sv(sv) {}
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bool sign() const { return 0 != (m_sv & 0x1); }
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lpvar var() const { return m_sv >> 1; }
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unsigned index() const { return m_sv; }
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void neg() { m_sv = m_sv ^ 1; }
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friend signed_var operator~(signed_var const& sv) {
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return signed_var(sv.var(), !sv.sign());
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}
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bool operator==(signed_var const& other) const {
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return m_sv == other.m_sv;
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}
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bool operator!=(signed_var const& other) const {
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return m_sv != other.m_sv;
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}
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};
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class signed_var {
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unsigned m_sv;
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public:
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// constructor, sign = true means minus
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signed_var(lpvar v, bool sign): m_sv((v << 1) + (sign ? 1 : 0)) {}
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// constructor
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signed_var(unsigned sv, from_index): m_sv(sv) {}
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bool sign() const { return 0 != (m_sv & 0x1); }
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lpvar var() const { return m_sv >> 1; }
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unsigned index() const { return m_sv; }
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void neg() { m_sv = m_sv ^ 1; }
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friend signed_var operator~(signed_var const& sv) {
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return signed_var(sv.var(), !sv.sign());
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}
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bool operator==(signed_var const& other) const {
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return m_sv == other.m_sv;
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}
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bool operator!=(signed_var const& other) const {
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return m_sv != other.m_sv;
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}
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rational rsign() const { return sign() ? rational::minus_one() : rational::one(); }
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};
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class eq_justification {
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svector<lpcindex> m_cs;
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public:
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eq_justification(std::initializer_list<lpcindex> cs) {
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for (lpcindex c: cs)
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m_cs.push_back(c);
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class eq_justification {
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lpci m_cs[4];
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public:
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eq_justification(std::initializer_list<lpci> cs) {
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int i = 0;
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for (lpci c: cs) {
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m_cs[i++] = c;
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}
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void explain(lp::explanation& e) const {
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for (lpcindex c : m_cs)
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for (; i < 4; i++) {
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m_cs[i] = -1;
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}
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}
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void explain(lp::explanation& e) const {
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for (lpci c : m_cs)
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if (c + 1 != 0) // c != -1
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e.add(c);
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}
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};
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class var_eqs {
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struct justified_var {
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signed_var m_var;
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eq_justification m_j;
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justified_var(signed_var v, eq_justification const& j): m_var(v), m_j(j) {}
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};
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typedef svector<justified_var> justified_vars;
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struct dfs_frame {
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signed_var m_var;
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unsigned m_index;
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dfs_frame(signed_var v, unsigned i): m_var(v), m_index(i) {}
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};
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typedef std::pair<signed_var, signed_var> signed_var_pair;
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union_find_default_ctx m_ufctx;
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union_find<> m_uf;
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svector<signed_var_pair> m_trail;
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unsigned_vector m_trail_lim;
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vector<justified_vars> m_eqs; // signed_var-index -> justified_var corresponding to edges in a graph used to extract justifications.
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mutable svector<dfs_frame> m_todo;
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mutable svector<bool> m_marked;
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mutable unsigned_vector m_marked_trail;
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mutable svector<eq_justification> m_dfs_trail;
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public:
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var_eqs();
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/**
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\brief push a scope
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*/
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void push();
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/**
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\brief pop n scopes
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*/
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void pop(unsigned n);
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/**
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\brief merge equivalence classes for v1, v2 with justification j
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*/
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void merge(signed_var v1, signed_var v2, eq_justification const& j);
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void merge_plus(lpvar v1, lpvar v2, eq_justification const& j) { merge(signed_var(v1, false), signed_var(v2, false), j); }
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void merge_minus(lpvar v1, lpvar v2, eq_justification const& j) { merge(signed_var(v1, false), signed_var(v2, true), j); }
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/**
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\brief find equivalence class representative for v
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*/
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signed_var find(signed_var v) const;
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inline signed_var find(lpvar j) const {
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return find(signed_var(j, false));
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}
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inline bool is_root(lpvar j) const {
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signed_var sv = find(signed_var(j, false));
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return sv.var() == j;
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}
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bool vars_are_equiv(lpvar j, lpvar k) const {
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signed_var sj = find(signed_var(j, false));
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signed_var sk = find(signed_var(k, false));
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return sj.var() == sk.var();
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}
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/**
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\brief Returns eq_justifications for
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\pre find(v1) == find(v2)
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*/
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void explain(signed_var v1, signed_var v2, lp::explanation& e) const;
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inline
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void explain(lpvar v1, lpvar v2, lp::explanation & e) const {
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return explain(signed_var(v1, false), signed_var(v2, false), e);
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}
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inline void explain(lpvar j, lp::explanation& e) const {
|
||||
signed_var s(j, false);
|
||||
return explain(find(s), s, e);
|
||||
}
|
||||
|
||||
class iterator {
|
||||
var_eqs& m_ve; // context.
|
||||
unsigned m_idx; // index into a signed variable, same as union-find index
|
||||
bool m_touched; // toggle between initial and final state
|
||||
public:
|
||||
iterator(var_eqs& ve, unsigned idx, bool t) : m_ve(ve), m_idx(idx), m_touched(t) {}
|
||||
signed_var operator*() const {
|
||||
return signed_var(m_idx, from_index()); // 0 is needed to call the right constructor
|
||||
}
|
||||
iterator& operator++() { m_idx = m_ve.m_uf.next(m_idx); m_touched = true; return *this; }
|
||||
bool operator==(iterator const& other) const { return m_idx == other.m_idx && m_touched == other.m_touched; }
|
||||
bool operator!=(iterator const& other) const { return m_idx != other.m_idx || m_touched != other.m_touched; }
|
||||
};
|
||||
|
||||
class var_eqs {
|
||||
struct justified_var {
|
||||
signed_var m_var;
|
||||
eq_justification m_j;
|
||||
justified_var(signed_var v, eq_justification const& j): m_var(v), m_j(j) {}
|
||||
};
|
||||
typedef svector<justified_var> justified_vars;
|
||||
|
||||
struct dfs_frame {
|
||||
signed_var m_var;
|
||||
unsigned m_index;
|
||||
dfs_frame(signed_var v, unsigned i): m_var(v), m_index(i) {}
|
||||
};
|
||||
typedef std::pair<signed_var, signed_var> signed_var_pair;
|
||||
|
||||
union_find_default_ctx m_ufctx;
|
||||
union_find<> m_uf;
|
||||
svector<signed_var_pair> m_trail;
|
||||
unsigned_vector m_trail_lim;
|
||||
vector<justified_vars> m_eqs; // signed_var-index -> justified_var corresponding to edges in a graph used to extract justifications.
|
||||
|
||||
mutable svector<dfs_frame> m_todo;
|
||||
mutable svector<bool> m_marked;
|
||||
mutable unsigned_vector m_marked_trail;
|
||||
mutable svector<eq_justification> m_dfs_trail;
|
||||
|
||||
class eq_class {
|
||||
var_eqs& m_ve;
|
||||
signed_var m_v;
|
||||
public:
|
||||
var_eqs();
|
||||
eq_class(var_eqs& ve, signed_var v) : m_ve(ve), m_v(v) {}
|
||||
iterator begin() { return iterator(m_ve, m_v.index(), false); }
|
||||
iterator end() { return iterator(m_ve, m_v.index(), true); }
|
||||
};
|
||||
|
||||
/**
|
||||
\brief push a scope
|
||||
*/
|
||||
void push();
|
||||
eq_class equiv_class(signed_var v) { return eq_class(*this, v); }
|
||||
|
||||
/**
|
||||
\brief pop n scopes
|
||||
*/
|
||||
void pop(unsigned n);
|
||||
|
||||
/**
|
||||
\brief merge equivalence classes for v1, v2 with justification j
|
||||
*/
|
||||
void merge(signed_var v1, signed_var v2, eq_justification const& j);
|
||||
void merge_plus(lpvar v1, lpvar v2, eq_justification const& j) { merge(signed_var(v1, false), signed_var(v2, false), j); }
|
||||
void merge_minus(lpvar v1, lpvar v2, eq_justification const& j) { merge(signed_var(v1, false), signed_var(v2, true), j); }
|
||||
|
||||
/**
|
||||
\brief find equivalence class representative for v
|
||||
*/
|
||||
signed_var find(signed_var v) const;
|
||||
inline lpvar find(lpvar j, rational& sign) const {
|
||||
signed_var sv = find(signed_var(j, false));
|
||||
sign = sv.sign()? rational(-1) : rational(1);
|
||||
return sv.var();
|
||||
}
|
||||
|
||||
inline rational find_sign(lpvar j) const {
|
||||
signed_var sv = find(signed_var(j, false));
|
||||
return sv.sign()? rational(-1) : rational(1);
|
||||
}
|
||||
|
||||
inline lpvar find(lpvar j) const {
|
||||
signed_var sv = find(signed_var(j, false));
|
||||
return sv.var();
|
||||
}
|
||||
|
||||
inline bool is_root(lpvar j) const {
|
||||
signed_var sv = find(signed_var(j, false));
|
||||
return sv.var() == j;
|
||||
}
|
||||
bool vars_are_equiv(lpvar j, lpvar k) const {
|
||||
signed_var sj = find(signed_var(j, false));
|
||||
signed_var sk = find(signed_var(k, false));
|
||||
return sj.var() == sk.var();
|
||||
}
|
||||
/**
|
||||
\brief Returns eq_justifications for
|
||||
\pre find(v1) == find(v2)
|
||||
*/
|
||||
void explain(signed_var v1, signed_var v2, lp::explanation& e) const;
|
||||
inline
|
||||
void explain(lpvar v1, lpvar v2, lp::explanation & e) const {
|
||||
return explain(signed_var(v1), signed_var(v2), e);
|
||||
}
|
||||
|
||||
inline void explain(lpvar j, lp::explanation& e) const {
|
||||
signed_var s(j, false);
|
||||
return explain(find(s), s, e);
|
||||
}
|
||||
|
||||
class iterator {
|
||||
var_eqs& m_ve; // context.
|
||||
unsigned m_idx; // index into a signed variable, same as union-find index
|
||||
bool m_touched; // toggle between initial and final state
|
||||
public:
|
||||
iterator(var_eqs& ve, unsigned idx, bool t) : m_ve(ve), m_idx(idx), m_touched(t) {}
|
||||
signed_var operator*() const { return signed_var(m_idx); }
|
||||
iterator& operator++() { m_idx = m_ve.m_uf.next(m_idx); m_touched = true; return *this; }
|
||||
bool operator==(iterator const& other) const { return m_idx == other.m_idx && m_touched == other.m_touched; }
|
||||
bool operator!=(iterator const& other) const { return m_idx != other.m_idx || m_touched != other.m_touched; }
|
||||
};
|
||||
|
||||
class eq_class {
|
||||
var_eqs& m_ve;
|
||||
signed_var m_v;
|
||||
public:
|
||||
eq_class(var_eqs& ve, signed_var v) : m_ve(ve), m_v(v) {}
|
||||
iterator begin() { return iterator(m_ve, m_v.index(), false); }
|
||||
iterator end() { return iterator(m_ve, m_v.index(), true); }
|
||||
};
|
||||
|
||||
eq_class equiv_class(signed_var v) { return eq_class(*this, v); }
|
||||
|
||||
eq_class equiv_class(lpvar v) { return equiv_class(signed_var(v, false)); }
|
||||
};
|
||||
eq_class equiv_class(lpvar v) { return equiv_class(signed_var(v, false)); }
|
||||
};
|
||||
}
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue