delay internalization, relevancy (#4707)

* delay evaluation Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * Update bv_solver.cpp * delay internalize Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * compiler warnings Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * remove gc Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com> * add bv delay option Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
2025-08-23 11:37:54 +00:00 · 2020-09-23 17:12:01 -07:00 · 2020-09-23 17:12:01 -07:00 · 7c2bdfe3fb
commit 7c2bdfe3fb
parent 1e7998f03a
21 changed files with 584 additions and 122 deletions
--- a/src/sat/smt/sat_dual_solver.cpp
+++ b/src/sat/smt/sat_dual_solver.cpp
@ -0,0 +1,96 @@
+/*++
+Copyright (c) 2020 Microsoft Corporation
+
+Module Name:
+
+    sat_dual_solver.cpp
+
+Abstract:
+
+    Solver for obtaining implicant.
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2020-08-25
+
+--*/
+#include "sat/smt/sat_dual_solver.h"
+
+namespace sat {
+
+    dual_solver::dual_solver(reslimit& l):
+        m_solver(params_ref(), l)
+    {}
+
+    void dual_solver::push() {
+        m_solver.user_push(); 
+        m_roots_lim.push_back(m_roots.size());     
+        m_tracked_lim.push_back(m_tracked_stack.size());
+    }
+
+    void dual_solver::pop(unsigned num_scopes) {
+        m_solver.user_pop(num_scopes);
+        unsigned old_sz = m_roots_lim.size() - num_scopes;
+        m_roots.shrink(m_roots_lim[old_sz]);
+        m_roots_lim.shrink(old_sz);
+        for (unsigned v = m_tracked_stack.size(); v-- > m_tracked_lim[old_sz]; ) 
+            m_is_tracked[v] = false; 
+        m_tracked_stack.shrink(m_tracked_lim[old_sz]);
+        m_tracked_lim.shrink(old_sz);
+    }
+
+    bool_var dual_solver::ext2var(bool_var v) {
+        bool_var w = m_ext2var.get(v, null_bool_var);
+        if (null_bool_var == w) {
+            w = m_solver.mk_var();
+            m_ext2var.setx(v, w, null_bool_var);
+            m_var2ext.setx(w, v, null_bool_var);
+        }
+        return w;
+    }
+
+    void dual_solver::track_relevancy(bool_var v) {
+        v = ext2var(v);
+        if (!m_is_tracked.get(v, false)) {
+            m_is_tracked.setx(v, true, false);
+            m_tracked_stack.push_back(v);
+        }
+    }
+
+    literal dual_solver::ext2lit(literal lit) {
+        return literal(ext2var(lit.var()), lit.sign());
+    }
+
+    literal dual_solver::lit2ext(literal lit) {
+        return literal(m_var2ext[lit.var()], lit.sign());
+    }
+
+    void dual_solver::add_root(literal lit, unsigned sz, literal const* clause) {
+        for (unsigned i = 0; i < sz; ++i)
+            m_solver.mk_clause(ext2lit(lit), ~ext2lit(clause[i]), status::input());
+        m_roots.push_back(~ext2lit(lit));
+    }
+
+    void dual_solver::add_aux(unsigned sz, literal const* clause) {
+        m_lits.reset();
+        for (unsigned i = 0; i < sz; ++i) 
+            m_lits.push_back(ext2lit(clause[i]));
+        m_solver.mk_clause(sz, m_lits.c_ptr(), status::input());
+    }
+
+    bool dual_solver::operator()(solver const& s) {
+        m_solver.user_push();
+        m_solver.add_clause(m_roots.size(), m_roots.c_ptr(), status::input());
+        m_lits.reset();
+        for (bool_var v : m_tracked_stack)
+            m_lits.push_back(literal(v, l_false == s.value(m_var2ext[v])));
+        lbool is_sat = m_solver.check(m_lits.size(), m_lits.c_ptr());
+        m_core.reset();
+        if (is_sat == l_false) 
+            for (literal lit : m_solver.get_core())
+                m_core.push_back(lit2ext(lit));
+        TRACE("euf", m_solver.display(tout << m_core << "\n"););
+        m_solver.user_pop(1);
+        return is_sat == l_false;
+    }
+}