vvp/event.h

   1 #ifndef __event_H
   2 #define __event_H
   3 /*
   4  * Copyright (c) 2004 Stephen Williams (steve@icarus.com)
   5  *
   6  *    This source code is free software; you can redistribute it
   7  *    and/or modify it in source code form under the terms of the GNU
   8  *    General Public License as published by the Free Software
   9  *    Foundation; either version 2 of the License, or (at your option)
  10  *    any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  20  */
  21 #ifdef HAVE_CVS_IDENT
  22 #ident "$Id: event.h,v 1.13 2006/12/09 19:06:53 steve Exp $"
  23 #endif
  24
  25 # include  "vvp_net.h"
  26 # include  "pointers.h"
  27
  28 /*
  29  *  Event / edge detection functors
  30  */
  31
  32 /*
  33  * A "waitable" functor is one that the %wait instruction can wait
  34  * on. This includes the infrastructure needed to hold threads.
  35  */
  36 struct waitable_hooks_s {
  37
  38     public:
  39       waitable_hooks_s() : threads(0) { }
  40       vthread_t threads;
  41
  42     protected:
  43       void run_waiting_threads_();
  44 };
  45
  46 /*
  47  * The vvp_fun_edge functor detects events that are edges of various
  48  * types. This should be hooked to a vvp_net_t that is connected to
  49  * the output of a signal that we wish to watch for edges.
  50  */
  51 class vvp_fun_edge : public vvp_net_fun_t, public waitable_hooks_s {
  52
  53     public:
  54       typedef unsigned short edge_t;
  55       explicit vvp_fun_edge(edge_t e, bool debug_flag);
  56
  57       virtual ~vvp_fun_edge();
  58
  59       void recv_vec4(vvp_net_ptr_t port, const vvp_vector4_t&bit);
  60
  61     private:
  62       vvp_bit4_t bits_[4];
  63       edge_t edge_;
  64       bool debug_;
  65 };
  66
  67 extern const vvp_fun_edge::edge_t vvp_edge_posedge;
  68 extern const vvp_fun_edge::edge_t vvp_edge_negedge;
  69 extern const vvp_fun_edge::edge_t vvp_edge_none;
  70
  71 /*
  72  * The vvp_fun_anyedge functor checks to see if any value in an input
  73  * vector changes. Unlike the vvp_fun_edge, which watches for the LSB
  74  * of its inputs to change in a particular direction, the anyedge
  75  * functor looks at the entire input vector for any change.
  76  *
  77  * The anyedge is also different in that it can receive real
  78  * values. in this case, any detectable change in the real value leads
  79  * to an even trigger.
  80  */
  81 class vvp_fun_anyedge : public vvp_net_fun_t, public waitable_hooks_s {
  82
  83     public:
  84       explicit vvp_fun_anyedge(bool debug_flag);
  85       virtual ~vvp_fun_anyedge();
  86
  87       void recv_vec4(vvp_net_ptr_t port, const vvp_vector4_t&bit);
  88       void recv_real(vvp_net_ptr_t port, double bit);
  89
  90     private:
  91       bool debug_;
  92       vvp_vector4_t bits_[4];
  93         // In case I'm a real-valued event.
  94       double bitsr_[4];
  95 };
  96
  97 /*
  98  * This functor triggers anytime any input is set, no matter what the
  99  * value. This is similar to a named event, but it has no handle.
 100  */
 101 class vvp_fun_event_or : public vvp_net_fun_t, public waitable_hooks_s {
 102
 103     public:
 104       explicit vvp_fun_event_or();
 105       ~vvp_fun_event_or();
 106
 107       void recv_vec4(vvp_net_ptr_t port, const vvp_vector4_t&bit);
 108
 109     private:
 110 };
 111
 112 /*
 113  * A named event is simpler then a vvp_fun_edge in that it triggers on
 114  * any input at all to port-0. The idea here is that behavioral code
 115  * can use a %set/v instruction to trigger the event.
 116  */
 117 class vvp_named_event : public vvp_net_fun_t, public waitable_hooks_s {
 118
 119     public:
 120       explicit vvp_named_event(struct __vpiHandle*eh);
 121       ~vvp_named_event();
 122
 123       void recv_vec4(vvp_net_ptr_t port, const vvp_vector4_t&bit);
 124
 125     private:
 126       struct __vpiHandle*handle_;
 127 };
 128
 129
 130 /*
 131  * $Log: event.h,v $
 132  * Revision 1.13  2006/12/09 19:06:53  steve
 133  *  Handle vpiRealVal reads of signals, and real anyedge events.
 134  *
 135  * Revision 1.12  2006/11/22 06:10:05  steve
 136  *  Fix spurious event from net8 that is forced.
 137  *
 138  * Revision 1.11  2005/06/22 00:04:49  steve
 139  *  Reduce vvp_vector4 copies by using const references.
 140  *
 141  * Revision 1.10  2005/06/17 23:47:02  steve
 142  *  threads member for waitable_hook_s needs initailizing.
 143  *
 144  * Revision 1.9  2005/05/25 05:44:51  steve
 145  *  Handle event/or with specific, efficient nodes.
 146  *
 147  * Revision 1.8  2004/12/29 23:45:13  steve
 148  *  Add the part concatenation node (.concat).
 149  *
 150  *  Add a vvp_event_anyedge class to handle the special
 151  *  case of .event statements of edge type. This also
 152  *  frees the posedge/negedge types to handle all 4 inputs.
 153  *
 154  *  Implement table functor recv_vec4 method to receive
 155  *  and process vectors.
 156  *
 157  * Revision 1.7  2004/12/18 18:52:44  steve
 158  *  Rework named events and event/or.
 159  *
 160  * Revision 1.6  2004/12/11 02:31:29  steve
 161  *  Rework of internals to carry vectors through nexus instead
 162  *  of single bits. Make the ivl, tgt-vvp and vvp initial changes
 163  *  down this path.
 164  */
 165 #endif // __event_H