preparing handling of arrays/quantifiers, fix cover-related bugs reported by Arie

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/muz_qe/dl_mk_array_blast.h

@@ -0,0 +1,61 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    dl_mk_array_blast.h
+
+Abstract:
+
+    Remove array variables from rules.
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2012-11-23
+
+Revision History:
+
+--*/
+#ifndef _DL_MK_ARRAY_BLAST_H_
+#define _DL_MK_ARRAY_BLAST_H_
+
+#include"dl_context.h"
+#include"dl_rule_set.h"
+#include"dl_rule_transformer.h"
+#include "equiv_proof_converter.h"
+#include "array_decl_plugin.h"
+
+namespace datalog {
+
+    /**
+       \brief Blast occurrences of arrays in rules
+    */
+    class mk_array_blast : public rule_transformer::plugin {
+        context&        m_ctx;
+        ast_manager&    m;
+        array_util      a;
+        rule_manager&   rm;
+        params_ref      m_params;
+        th_rewriter     m_rewriter;
+        equiv_proof_converter* m_pc;
+
+        bool blast(rule& r, rule_set& new_rules);
+
+        bool is_store_def(expr* e, expr*& x, expr*& y);
+
+    public:
+        /**
+           \brief Create rule transformer that extracts universal quantifiers (over recursive predicates).
+        */
+        mk_array_blast(context & ctx, unsigned priority);
+
+        virtual ~mk_array_blast();
+        
+        rule_set * operator()(rule_set const & source, model_converter_ref& mc, proof_converter_ref& pc);
+
+    };
+
+};
+
+#endif /* _DL_MK_ARRAY_BLAST_H_ */
+