Z3 sources

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

lib/nlsat_scoped_literal_vector.h

@@ -0,0 +1,89 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    nlsat_scoped_literal_vector.h
+
+Abstract:
+
+    Scoped vector for nlsat literals.
+    Just to be "cancel" safe.
+
+Author:
+
+    Leonardo de Moura (leonardo) 2012-01-13.
+
+Revision History:
+
+--*/
+#ifndef _NLSAT_SCOPED_LITERAL_VECTOR_H_
+#define _NLSAT_SCOPED_LITERAL_VECTOR_H_
+
+#include"nlsat_solver.h"
+
+namespace nlsat {
+
+    class scoped_literal_vector {
+        solver &       m_solver;
+        literal_vector m_lits;
+    public:
+        scoped_literal_vector(solver & s):m_solver(s) {}
+        ~scoped_literal_vector() { reset(); }
+        unsigned size() const { return m_lits.size(); }
+        bool empty() const { return m_lits.empty(); }
+        literal operator[](unsigned i) const { return m_lits[i]; }
+        void reset() {
+            unsigned sz = m_lits.size();
+            for (unsigned i = 0; i < sz; i++) {
+                m_solver.dec_ref(m_lits[i]);
+            }
+            m_lits.reset();
+        }
+        void push_back(literal l) {
+            m_solver.inc_ref(l);
+            m_lits.push_back(l);
+        }
+        void set(unsigned i, literal l) {
+            m_solver.inc_ref(l);
+            m_solver.dec_ref(m_lits[i]);
+            m_lits[i] = l;
+        }
+        literal const * c_ptr() const { return m_lits.c_ptr(); }
+        void shrink(unsigned new_sz) {
+            SASSERT(new_sz <= m_lits.size());
+            unsigned sz = m_lits.size();
+            if (new_sz == sz)
+                return;
+            for (unsigned i = new_sz; i < sz; i++) {
+                m_solver.dec_ref(m_lits[i]);
+            }
+            m_lits.shrink(new_sz);
+        }
+        void append(unsigned sz, literal const * ls) {
+            for (unsigned i = 0; i < sz; i++)
+                push_back(ls[i]);
+        }
+    };
+
+
+    class scoped_literal {
+        solver &  m_solver;
+        literal   m_lit;
+    public:
+        scoped_literal(solver & s):m_solver(s), m_lit(null_literal) {}
+        ~scoped_literal() { m_solver.dec_ref(m_lit); }
+        scoped_literal & operator=(literal l) { 
+            m_solver.inc_ref(l);
+            m_solver.dec_ref(m_lit);
+            m_lit = l;
+            return *this;
+        }
+        scoped_literal & operator=(scoped_literal const & l) { return operator=(l.m_lit); }
+        operator literal&() { return m_lit; }
+        operator literal const &() const { return m_lit; }
+        void neg() { m_lit.neg(); }
+    };
+};
+
+#endif