Polysat: refactor constraints (#5372)

* Refactor: remove sign and dep from constraint

* fix some bugs

* improve log messages

* Add missing premises to lemma

* Rename getter in an attempt to fix linux build

src/math/polysat/clause_builder.cpp

@@ -0,0 +1,68 @@
+/*++
+Copyright (c) 2021 Microsoft Corporation
+
+Module Name:
+
+    polysat clause builder
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2021-03-19
+    Jakob Rath 2021-04-6
+
+--*/
+
+#include "math/polysat/clause_builder.h"
+#include "math/polysat/solver.h"
+#include "math/polysat/log.h"
+
+namespace polysat {
+
+    clause_builder::clause_builder(solver& s):
+        m_solver(s), m_dep(nullptr, s.m_dm)
+    {}
+
+    void clause_builder::reset() {
+        m_literals.reset();
+        m_new_constraints.reset();
+        m_level = 0;
+        m_dep = nullptr;
+        SASSERT(empty());
+    }
+
+    clause_ref clause_builder::build() {
+        // TODO: here we could set all the levels of the new constraints. so we do not have to compute the max at every use site.
+        clause_ref cl = clause::from_literals(m_level, std::move(m_dep), std::move(m_literals), std::move(m_new_constraints));
+        m_level = 0;
+        SASSERT(empty());
+        return cl;
+    }
+
+    void clause_builder::add_dependency(p_dependency* d) {
+        m_dep = m_solver.m_dm.mk_join(m_dep, d);
+    }
+
+    void clause_builder::push_literal(sat::literal lit) {
+        constraint* c = m_solver.m_constraints.lookup(lit.var());
+        SASSERT(c);
+        if (c->unit_clause()) {
+            add_dependency(c->unit_clause()->dep());
+            return;
+        }
+        m_level = std::max(m_level, c->level());
+        m_literals.push_back(lit);
+    }
+
+    void clause_builder::push_new_constraint(constraint_literal c) {
+        // TODO: assert that constraint is new (not 'inserted' into manager yet)
+        SASSERT(c);
+        SASSERT(c->is_undef());
+        tmp_assign _t(c.get(), c.literal());
+        if (c->is_always_false())
+            return;
+        m_level = std::max(m_level, c->level());
+        m_literals.push_back(c.literal());
+        m_new_constraints.push_back(c.detach());
+    }
+
+}