Z3 sources

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

lib/pdr_interpolant_provider.h

@@ -0,0 +1,54 @@
+/*++
+Copyright (c) 2011 Microsoft Corporation
+
+Module Name:
+
+    interpolant_provider.h
+
+Abstract:
+
+    Interface for obtaining interpolants.
+
+Author:
+
+    Krystof Hoder (t-khoder) 2011-10-19.
+
+Revision History:
+
+--*/
+
+#include "ast.h"
+#include "lbool.h"
+#include "model.h"
+#include "params.h"
+
+#ifndef _PDR_INTERPOLANT_PROVIDER_H_
+#define _PDR_INTERPOLANT_PROVIDER_H_
+
+class interpolant_provider
+{
+protected:
+    ast_manager & m;
+
+    interpolant_provider(ast_manager& m) : m(m) {}
+
+public:
+
+    virtual ~interpolant_provider() {}
+
+    /**
+    If (f1 /\ f2) is unsatisfiable, return true and into res assign a formula
+    I such that f1 --> I, I --> ~f2, and the language if I is in the intersection 
+    of languages of f1 and f2.
+
+    If (f1 /\ f2) is satisfiable, return false.
+    */
+    virtual lbool get_interpolant(expr * f1, expr * f2, expr_ref& res) = 0;
+
+    static interpolant_provider * mk(ast_manager& m, params_ref const& p);
+
+    static void output_interpolant(ast_manager& m, expr* A, expr* B, expr* I);
+};
+
+
+#endif