refactor weighted-maxsat into separate files

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

src/opt/maxsls.cpp

@@ -0,0 +1,63 @@
+/*++
+Copyright (c) 2013 Microsoft Corporation
+
+Module Name:
+
+    maxsls.cpp
+
+Abstract:
+
+    Weighted SLS MAXSAT module
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2014-4-17
+
+Notes:
+
+--*/
+
+#include "maxsls.h"
+#include "ast_pp.h"
+#include "model_smt2_pp.h"
+
+
+namespace opt {
+
+    class sls : public maxsmt_solver_base {
+    public:
+        sls(opt_solver* s, ast_manager& m, params_ref& p, 
+            vector<rational> const& ws, expr_ref_vector const& soft): 
+            maxsmt_solver_base(s, m, p, ws, soft) {
+        }
+        virtual ~sls() {}
+        lbool operator()() {
+            IF_VERBOSE(1, verbose_stream() << "(opt.sls)\n";);
+            enable_bvsat();
+            enable_sls();
+            init();
+            lbool is_sat = s().check_sat(0, 0);
+            if (is_sat == l_true) {
+                s().get_model(m_model);
+                m_upper.reset();
+                for (unsigned i = 0; i < m_soft.size(); ++i) {
+                    expr_ref tmp(m);
+                    m_model->eval(m_soft[i].get(), tmp, true);
+                    m_assignment[i] = m.is_true(tmp);
+                    if (!m_assignment[i]) {
+                        m_upper += m_weights[i];
+                    }
+                }
+            }
+            return is_sat;
+        }
+
+    };
+
+    maxsmt_solver_base* opt::mk_sls(ast_manager& m, opt_solver* s, params_ref& p, 
+                                    vector<rational> const& ws, expr_ref_vector const& soft) {
+        return alloc(sls, s, m, p, ws, soft);
+    }
+
+
+};