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diff --git a/ext/systemc/src/sysc/communication/sc_writer_policy.h b/ext/systemc/src/sysc/communication/sc_writer_policy.h
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+/*****************************************************************************
+
+  Licensed to Accellera Systems Initiative Inc. (Accellera) under one or
+  more contributor license agreements.  See the NOTICE file distributed
+  with this work for additional information regarding copyright ownership.
+  Accellera licenses this file to you under the Apache License, Version 2.0
+  (the "License"); you may not use this file except in compliance with the
+  License.  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+  implied.  See the License for the specific language governing
+  permissions and limitations under the License.
+
+ *****************************************************************************/
+
+/*****************************************************************************
+
+  sc_writer_policy.h -- The sc_signal<T> writer policy definition
+
+  Original Author: Philipp A: Hartmann, OFFIS
+
+  CHANGE LOG IS AT THE END OF THE FILE
+ *****************************************************************************/
+
+
+#ifndef SC_WRITER_POLICY_H_INCLUDED_
+#define SC_WRITER_POLICY_H_INCLUDED_
+
+#if !defined(SC_DEFAULT_WRITER_POLICY)
+#  if defined(SC_NO_WRITE_CHECK)
+#    define SC_DEFAULT_WRITER_POLICY SC_UNCHECKED_WRITERS
+#  else
+#    define SC_DEFAULT_WRITER_POLICY SC_ONE_WRITER
+#  endif
+#endif
+
+namespace sc_core {
+
+class sc_object;
+class sc_port_base;
+extern
+void
+sc_signal_invalid_writer( sc_object* target, sc_object* first_writer,
+                          sc_object* second_writer, bool check_delta );
+
+// SIGNAL WRITING POLICIES
+//
+// Note: if you add a new policy to the enum below you will need to add
+// an additional overload of sc_reset::reset_signal_is() for the sc_signal<bool>
+// instance. That will require changes to sysc/kernel/sc_reset.cpp and 
+// sysc/kernel/sc_reset.h
+
+enum sc_writer_policy
+{
+  SC_ONE_WRITER        = 0, ///< unique writer (from a unique port)
+  SC_MANY_WRITERS      = 1, ///< allow multiple writers (with different ports)
+  SC_UNCHECKED_WRITERS = 3  ///< even allow delta cycle conflicts (non-standard)
+};
+
+// signal forward declaration
+template< typename T, sc_writer_policy POL = SC_DEFAULT_WRITER_POLICY >
+class sc_signal;
+
+template< sc_writer_policy >
+struct sc_writer_policy_check;
+
+struct sc_writer_policy_nocheck_write
+{
+  bool check_write( sc_object* /* target */, bool /* value_changed */ )
+    { return true; }
+  void update(){}
+};
+
+struct sc_writer_policy_check_write
+{
+  bool check_write( sc_object* target, bool value_changed );
+  void update(){}
+protected:
+  sc_writer_policy_check_write( bool check_delta = false )
+    : m_check_delta( check_delta ), m_writer_p(NULL) {}
+  const bool         m_check_delta;
+  sc_object*         m_writer_p;
+};
+
+struct sc_writer_policy_check_delta
+    : sc_writer_policy_check_write
+{
+
+  sc_writer_policy_check_delta()
+    : sc_writer_policy_check_write(true) {}
+
+  bool check_write( sc_object* target, bool value_changed )
+  {
+      if( value_changed )
+          return sc_writer_policy_check_write::check_write( target, true );
+      return true;
+  }
+
+  void update(){ m_writer_p = NULL; }
+};
+
+struct sc_writer_policy_nocheck_port
+{
+  bool check_port( sc_object*, sc_port_base*, bool )
+    { return true; }
+};
+
+struct sc_writer_policy_check_port
+{
+  bool check_port( sc_object* target, sc_port_base* port, bool is_output );
+
+protected:
+  sc_writer_policy_check_port() : m_output(0) {}
+  sc_port_base* m_output;
+};
+
+template<>
+struct sc_writer_policy_check<SC_ONE_WRITER>
+  : sc_writer_policy_check_port
+  , sc_writer_policy_check_write
+{};
+
+template<>
+struct sc_writer_policy_check<SC_MANY_WRITERS>
+  : sc_writer_policy_nocheck_port
+  , sc_writer_policy_check_delta
+{};
+
+template<>
+struct sc_writer_policy_check<SC_UNCHECKED_WRITERS>
+  : sc_writer_policy_nocheck_port
+  , sc_writer_policy_nocheck_write
+{};
+
+} // namespace sc_core
+
+#endif
+
+// Taf!