old_params ==> front_end_params. Isolated abstract solver interface

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

src/solver/solver.h

@@ -0,0 +1,153 @@
+/*++
+Copyright (c) 2011 Microsoft Corporation
+
+Module Name:
+
+    solver.h
+
+Abstract:
+
+    abstract solver interface
+
+Author:
+
+    Leonardo (leonardo) 2011-03-19
+
+Notes:
+
+--*/
+#ifndef _SOLVER_H_
+#define _SOLVER_H_
+
+#include"check_sat_result.h"
+#include"progress_callback.h"
+#include"params.h"
+
+struct front_end_params;
+
+/**
+   \brief Abstract interface for making solvers available in the Z3
+   API and front-ends such as SMT 2.0 and (legacy) SMT 1.0.
+
+   It provides the basic functionality for incremental solvers.
+     - assertions
+     - push/pop
+     - parameter setting (updt_params)
+     - statistics
+     - results based on check_sat_result API
+     - interruption (set_cancel)
+     - resets 
+*/
+class solver : public check_sat_result {
+public:
+    virtual ~solver() {}
+    
+    /**
+       \brief This method is invoked to allow the solver to access the front_end_params (environment parameters).
+       
+       \warning This method is used for backward compatibility. The first solver implemented in Z3 used
+       front_end_params to store its configuration parameters. 
+    */
+    virtual void set_front_end_params(front_end_params & p) {} 
+
+    /**
+       \brief Update the solver internal settings. 
+    */
+    virtual void updt_params(params_ref const & p) {}
+
+    /**
+       \brief Store in \c r a description of the configuration
+       parameters available in this solver.
+    */
+    virtual void collect_param_descrs(param_descrs & r) {}
+    
+    /**
+       \brief Enable/Disable proof production for this solver object.
+    
+       It is invoked before init(m, logic).
+    */
+    virtual void set_produce_proofs(bool f) {}
+    /**
+       \brief Enable/Disable model generation for this solver object.
+
+       It is invoked before init(m, logic).
+    */
+    virtual void set_produce_models(bool f) {}
+    /**
+       \brief Enable/Disable unsat core generation for this solver object.
+
+       It is invoked before init(m, logic).
+    */
+    virtual void set_produce_unsat_cores(bool f) {}
+    
+    /**
+       \brief Initialize the solver object with the given ast_manager and logic.
+    */
+    virtual void init(ast_manager & m, symbol const & logic) = 0;
+    
+    /**
+       \brief Reset the solver internal state. All assertions should be removed.
+    */
+    virtual void reset() = 0;
+
+    /**
+       \brief Add a new formula to the assertion stack.
+    */
+    virtual void assert_expr(expr * t) = 0;
+
+    /**
+       \brief Create a backtracking point.
+    */
+    virtual void push() = 0;
+
+    /**
+       \brief Remove \c n backtracking points. All assertions between the pop and matching push are removed. 
+    */
+    virtual void pop(unsigned n) = 0;
+
+    /**
+       \brief Return the number of backtracking points.
+    */
+    virtual unsigned get_scope_level() const = 0;
+
+    /**
+       \brief Check if the set of assertions in the assertion stack is satisfiable modulo the given assumptions.
+       
+       If it is unsatisfiable, and unsat-core generation is enabled. Then, the unsat-core is a subset of these assumptions.
+    */
+    virtual lbool check_sat(unsigned num_assumptions, expr * const * assumptions) = 0;
+
+    virtual void set_cancel(bool f) {}
+    /**
+       \brief Interrupt this solver.
+    */
+    void cancel() { set_cancel(true); }
+    /**
+       \brief Reset the interruption.
+    */
+    void reset_cancel() { set_cancel(false); }
+
+    /**
+       \brief Set a progress callback procedure that is invoked by this solver during check_sat.
+       
+       This is essentially for backward compatibility and integration with VCC tools.
+    */
+    virtual void set_progress_callback(progress_callback * callback) = 0;
+    
+    /**
+       \brief Return the number of assertions in the assertion stack.
+    */
+    virtual unsigned get_num_assertions() const;
+
+    /**
+       \brief Return the assertion at position idx in the assertion stack.
+    */
+    virtual expr * get_assertion(unsigned idx) const;
+
+    /**
+       \brief Display the content of this solver.
+    */
+    virtual void display(std::ostream & out) const;
+};
+
+#endif