ensure that seq rewriter gets invoked during pre-processing

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

src/ast/simplifier/seq_simplifier_plugin.cpp

@@ -0,0 +1,39 @@
+/*++
+Copyright (c) 2016 Microsoft Corporation
+
+Module Name:
+
+    seq_simplifier_plugin.cpp
+
+Abstract:
+
+    Simplifier for the floating-point theory
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2016-02-05
+
+--*/
+#include"seq_simplifier_plugin.h"
+
+seq_simplifier_plugin::seq_simplifier_plugin(ast_manager & m, basic_simplifier_plugin & b) :
+simplifier_plugin(symbol("seq"), m),
+m_util(m),
+m_rw(m) {}
+
+seq_simplifier_plugin::~seq_simplifier_plugin() {}
+
+bool seq_simplifier_plugin::reduce(func_decl * f, unsigned num_args, expr * const * args, expr_ref & result) {
+    set_reduce_invoked();    
+
+    SASSERT(f->get_family_id() == get_family_id());
+
+    return m_rw.mk_app_core(f, num_args, args, result) != BR_FAILED;
+}
+
+bool seq_simplifier_plugin::reduce_eq(expr * lhs, expr * rhs, expr_ref & result) {
+    set_reduce_invoked();
+
+    return m_rw.mk_eq_core(lhs, rhs, result) != BR_FAILED;
+}
+

src/ast/simplifier/seq_simplifier_plugin.h

@@ -0,0 +1,39 @@
+/*++
+Copyright (c) 2016 Microsoft Corporation
+
+Module Name:
+
+    seq_simplifier_plugin.h
+
+Abstract:
+
+    Simplifier for the sequence theory
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2016-02-05
+
+--*/
+#ifndef SEQ_SIMPLIFIER_PLUGIN_H_
+#define SEQ_SIMPLIFIER_PLUGIN_H_
+
+#include"basic_simplifier_plugin.h"
+#include"seq_decl_plugin.h"
+#include"seq_rewriter.h"
+
+class seq_simplifier_plugin : public simplifier_plugin {
+    seq_util     m_util;
+    seq_rewriter m_rw;
+
+public:
+    seq_simplifier_plugin(ast_manager & m, basic_simplifier_plugin & b);
+    ~seq_simplifier_plugin();
+
+
+    virtual bool reduce(func_decl * f, unsigned num_args, expr * const * args, expr_ref & result);
+
+    virtual bool reduce_eq(expr * lhs, expr * rhs, expr_ref & result);
+
+};
+
+#endif /* SEQ_SIMPLIFIER_PLUGIN_H_ */