Z3 sources

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

lib/smt_for_each_relevant_expr.h

@@ -0,0 +1,114 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    smt_for_each_relevant_expr.h
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Leonardo de Moura (leonardo) 2009-01-05.
+
+Revision History:
+
+--*/
+#ifndef _SMT_FOR_EACH_RELEVANT_EXPR_H_
+#define _SMT_FOR_EACH_RELEVANT_EXPR_H_
+
+#include"ast.h"
+#include"obj_hashtable.h"
+#include"vector.h"
+
+namespace smt {
+
+    class context;
+   
+
+    class check_at_labels {
+        ast_manager &       m_manager;
+        bool                m_first;
+        unsigned count_at_labels_pos(expr* n);
+        unsigned count_at_labels_neg(expr* n);
+        unsigned count_at_labels_lit(expr* n, bool polarity);
+
+    public:
+        check_at_labels(ast_manager& m) : m_manager(m) {};
+
+        /**
+           \brief Check that 'n' as a formula contains at most one @ label within each and-or path.
+        */
+
+        bool check(expr* cnstr);
+    };
+    /**
+       \brief Functor used to traverse the relevant expressions in a logical context.
+    */
+    class for_each_relevant_expr {
+    protected:
+        ast_manager &       m_manager;
+        context &           m_context;
+        obj_hashtable<expr> m_cache;
+        ptr_vector<expr>    m_todo;
+        bool                m_first;
+
+        void process_app(app * n);
+        void process_relevant_child(app * n, lbool val);
+        void process_and(app * n);
+        void process_or(app * n);
+        void process_ite(app * n);
+        lbool get_assignment(expr * n);
+        bool is_relevant(expr * n);
+
+
+    public:
+        for_each_relevant_expr(context & ctx);
+        virtual ~for_each_relevant_expr() {}
+        /**
+           \brief Visit the relevant sub-expressions of n.
+           That is, only subexpressions m of n, such that m_context.is_relevant(m).
+           This method also tries to minimize the number of subexpressions visited.
+           For each visited expression the method operator() is invoked.
+           Only not-already-visited expressions are visited.
+        */
+        void process(expr * n);
+
+        /**
+           \see process
+        */
+        virtual void operator()(expr * n);
+        /**
+           \brief Reset the cache of already visited expressions.
+        */
+        void reset();
+    };
+
+    class collect_relevant_label_lits : public for_each_relevant_expr {
+        buffer<symbol> & m_buffer;
+    public:
+        collect_relevant_label_lits(context & ctx, buffer<symbol> & b):
+            for_each_relevant_expr(ctx),
+            m_buffer(b) {
+        }
+        virtual ~collect_relevant_label_lits() {}
+        virtual void operator()(expr * n);
+    };
+
+    class collect_relevant_labels : public for_each_relevant_expr {
+        buffer<symbol> & m_buffer;
+    public:
+        collect_relevant_labels(context & ctx, buffer<symbol> & b):
+            for_each_relevant_expr(ctx),
+            m_buffer(b) {
+        }
+        virtual ~collect_relevant_labels() {}
+        virtual void operator()(expr * n);
+    };
+
+};
+
+#endif /* _SMT_FOR_EACH_RELEVANT_EXPR_H_ */
+