net_func.cc

   1 /*
   2  * Copyright (c) 2002-2004 Stephen Williams (steve@icarus.com)
   3  *
   4  *    This source code is free software; you can redistribute it
   5  *    and/or modify it in source code form under the terms of the GNU
   6  *    General Public License as published by the Free Software
   7  *    Foundation; either version 2 of the License, or (at your option)
   8  *    any later version.
   9  *
  10  *    This program is distributed in the hope that it will be useful,
  11  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *    GNU General Public License for more details.
  14  *
  15  *    You should have received a copy of the GNU General Public License
  16  *    along with this program; if not, write to the Free Software
  17  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  18  */
  19 #ifdef HAVE_CVS_IDENT
  20 #ident "$Id: net_func.cc,v 1.10 2007/06/02 03:42:13 steve Exp $"
  21 #endif
  22
  23 # include  "config.h"
  24 # include  "netlist.h"
  25 # include  "compiler.h"
  26 # include  "PExpr.h"
  27 # include  <iostream>
  28
  29 /*
  30  * To make a NetUserFunc device, make as many pins as there are ports
  31  * in the function. Get the port count from the function definition,
  32  * which accounts for all the inputs, plus one for the phantom output
  33  * that is the result.
  34  */
  35 NetUserFunc::NetUserFunc(NetScope*s, perm_string n, NetScope*d)
  36 : NetNode(s, n, d->func_def()->port_count()+1),
  37   def_(d)
  38 {
  39       pin(0).set_dir(Link::OUTPUT);
  40       pin(0).set_name(def_->basename(), 0);
  41
  42       for (unsigned idx = 1 ;  idx < pin_count() ;  idx += 1) {
  43
  44             pin(idx).set_dir(Link::INPUT);
  45             pin(idx).set_name(perm_string::literal("D"), idx-1);
  46             pin(idx).drive0(Link::HIGHZ);
  47             pin(idx).drive1(Link::HIGHZ);
  48       }
  49 }
  50
  51 NetUserFunc::~NetUserFunc()
  52 {
  53 }
  54
  55 unsigned NetUserFunc::port_width(unsigned port) const
  56 {
  57       NetFuncDef*def = def_->func_def();
  58
  59         /* Port 0 is the return port. */
  60       if (port == 0) {
  61             const NetNet*sig = def->return_sig();
  62             assert(sig);
  63             return sig->vector_width();
  64       }
  65
  66       port -= 1;
  67       assert(port < def->port_count());
  68       const NetNet*port_sig = def->port(port);
  69
  70       return port_sig->vector_width();
  71 }
  72
  73 const NetScope* NetUserFunc::def() const
  74 {
  75       return def_;
  76 }
  77
  78 /*
  79  * This method of the PECallFunction class checks that the parameters
  80  * of the PECallFunction match the function definition. This is used
  81  * during elaboration to validate the parameters before using them.
  82  */
  83 bool PECallFunction::check_call_matches_definition_(Design*des, NetScope*dscope) const
  84 {
  85       assert(dscope);
  86
  87         /* How many parameters have I got? Normally the size of the
  88            list is correct, but there is the special case of a list of
  89            1 nil pointer. This is how the parser tells me of no
  90            parameter. In other words, ``func()'' is 1 nil parameter. */
  91
  92       unsigned parms_count = parms_.count();
  93       if ((parms_count == 1) && (parms_[0] == 0))
  94             parms_count = 0;
  95
  96       if (dscope->type() != NetScope::FUNC) {
  97             cerr << get_line() << ": error: Attempt to call scope "
  98                  << scope_path(dscope) << " as a function." << endl;
  99             des->errors += 1;
 100             return false;
 101       }
 102
 103       if (parms_count != dscope->func_def()->port_count()) {
 104             cerr << get_line() << ": error: Function " << scope_path(dscope)
 105                  << " expects " << (dscope->func_def()->port_count())
 106                  << " arguments, you passed " << parms_count << "."
 107                  << endl;
 108             des->errors += 1;
 109             return false;
 110       }
 111
 112       return true;
 113 }
 114
 115
 116 NetSysFunc::NetSysFunc(NetScope*s, perm_string n,
 117                        const struct sfunc_return_type*def,
 118                        unsigned ports)
 119 : NetNode(s, n, ports)
 120 {
 121       def_ = def;
 122
 123       pin(0).set_dir(Link::OUTPUT);
 124       pin(0).set_name(perm_string::literal("Q"), 0);
 125
 126       for (unsigned idx = 1 ;  idx < pin_count() ;  idx += 1) {
 127
 128             pin(idx).set_dir(Link::INPUT);
 129             pin(idx).set_name(perm_string::literal("D"), idx-1);
 130             pin(idx).drive0(Link::HIGHZ);
 131             pin(idx).drive1(Link::HIGHZ);
 132       }
 133 }
 134
 135 NetSysFunc::~NetSysFunc()
 136 {
 137 }
 138
 139 const char*NetSysFunc::func_name() const
 140 {
 141       return def_->name;
 142 }
 143
 144 unsigned NetSysFunc::vector_width() const
 145 {
 146       return def_->wid;
 147 }
 148
 149
 150 /*
 151  * $Log: net_func.cc,v $
 152  * Revision 1.10  2007/06/02 03:42:13  steve
 153  *  Properly evaluate scope path expressions.
 154  *
 155  * Revision 1.9  2007/04/17 04:17:47  steve
 156  *  Fix argument count in function error message.
 157  *
 158  * Revision 1.8  2006/06/18 04:15:50  steve
 159  *  Add support for system functions in continuous assignments.
 160  *
 161  * Revision 1.7  2005/03/18 02:56:03  steve
 162  *  Add support for LPM_UFUNC user defined functions.
 163  *
 164  * Revision 1.6  2004/05/31 23:34:37  steve
 165  *  Rewire/generalize parsing an elaboration of
 166  *  function return values to allow for better
 167  *  speed and more type support.
 168  *
 169  * Revision 1.5  2004/02/18 17:11:56  steve
 170  *  Use perm_strings for named langiage items.
 171  *
 172  * Revision 1.4  2003/03/06 00:28:41  steve
 173  *  All NetObj objects have lex_string base names.
 174  *
 175  * Revision 1.3  2002/08/12 01:34:59  steve
 176  *  conditional ident string using autoconfig.
 177  *
 178  * Revision 1.2  2002/03/31 04:07:40  steve
 179  *  Update for gcc 3.0
 180  *
 181  * Revision 1.1  2002/03/09 02:10:22  steve
 182  *  Add the NetUserFunc netlist node.
 183  *
 184  */
 185