packet_constraint.h

SystemC片上系统设计的源代码： 书籍介绍： SystemC是被实践证明的优秀的系统设计描述语言

#include "packet_ext.h"

// nbcode "class" start
//create a basic constraint for the packet generator
struct packet_base_constraint : public scv_constraint_base {
  //create a packet object
  scv_smart_ptr<packet_t> packet;

  //put the base constraints on the packet variables
  SCV_CONSTRAINT_CTOR(packet_base_constraint) {
    SCV_CONSTRAINT ( packet->msg_length() < 80 );
    SCV_CONSTRAINT ( packet->msg_length() > 2 );
    SCV_CONSTRAINT ( packet->src_addr() != packet->dest_addr() );

    for (int i=0; i<1024; ++i) {
      //make the msg alpha numeric
      packet->msg[i] = '\0';

      //you can use keep_only/keep_out only if the element you
      //are constraining is NOT involved in SCV_CONSTRAINTS in
      //any way. In this case, msg is independent of other things.
      packet->msg[i].keep_only(' ', 'z');  //ascii space to z
      packet->msg[i].keep_out('!', '/');   //punctuation characters
      packet->msg[i].keep_out(':', '@');   //more special characters
      packet->msg[i].keep_out('[', '`');   //more special characters
    }
  }
};
// nbcode "class" end