elab_anet.cc

   1 /*
   2  * Copyright (c) 2000-2003 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: elab_anet.cc,v 1.13 2007/03/22 16:08:14 steve Exp $"
  21 #endif
  22
  23 # include "config.h"
  24
  25 /*
  26  * The elaborate_anet methods elaborate expressions that are intended
  27  * to be the left side of procedural continuous assignments.
  28  */
  29
  30 # include  "PExpr.h"
  31 # include  "netlist.h"
  32 # include  "netmisc.h"
  33 # include  <iostream>
  34
  35 NetNet* PExpr::elaborate_anet(Design*des, NetScope*scope) const
  36 {
  37       cerr << get_line() << ": error: Invalid expression on left side "
  38            << "of procedural continuous assignment." << endl;
  39       return 0;
  40 }
  41
  42
  43 NetNet* PEConcat::elaborate_anet(Design*des, NetScope*scope) const
  44 {
  45       if (repeat_) {
  46             cerr << get_line() << ": error: Repeat concatenations make "
  47                   "no sense in l-value expressions. I refuse." << endl;
  48             des->errors += 1;
  49             return 0;
  50       }
  51
  52       svector<NetNet*>nets (parms_.count());
  53       unsigned pins = 0;
  54       unsigned errors = 0;
  55
  56       for (unsigned idx = 0 ;  idx < nets.count() ;  idx += 1) {
  57
  58             if (parms_[idx] == 0) {
  59                   cerr << get_line() << ": error: Empty expressions "
  60                        << "not allowed in concatenations." << endl;
  61                   errors += 1;
  62                   continue;
  63             }
  64
  65             nets[idx] = parms_[idx]->elaborate_anet(des, scope);
  66             if (nets[idx] == 0)
  67                   errors += 1;
  68             else
  69                   pins += nets[idx]->pin_count();
  70       }
  71
  72         /* If any of the sub expressions failed to elaborate, then
  73            delete all those that did and abort myself. */
  74       if (errors) {
  75             for (unsigned idx = 0 ;  idx < nets.count() ;  idx += 1) {
  76                   if (nets[idx]) delete nets[idx];
  77             }
  78             des->errors += 1;
  79             return 0;
  80       }
  81
  82         /* Make the temporary signal that connects to all the
  83            operands, and connect it up. Scan the operands of the
  84            concat operator from least significant to most significant,
  85            which is opposite from how they are given in the list.
  86
  87            Allow for a repeat count other than 1 by repeating the
  88            connect loop as many times as necessary. */
  89
  90       NetNet*osig = new NetNet(scope, scope->local_symbol(),
  91                                NetNet::IMPLICIT_REG, pins);
  92         /* Assume that all the data types are the same. */
  93       osig->data_type(nets[0]->data_type());
  94
  95       pins = 0;
  96       for (unsigned idx = nets.count() ;  idx > 0 ;  idx -= 1) {
  97             NetNet*cur = nets[idx-1];
  98             assert(cur->data_type() == osig->data_type());
  99             for (unsigned pin = 0;  pin < cur->pin_count();  pin += 1) {
 100                   connect(osig->pin(pins), cur->pin(pin));
 101                   pins += 1;
 102             }
 103       }
 104
 105       osig->local_flag(true);
 106       return osig;
 107 }
 108
 109 NetNet* PEIdent::elaborate_anet(Design*des, NetScope*scope) const
 110 {
 111       assert(scope);
 112
 113       NetNet*       sig = 0;
 114       NetMemory*    mem = 0;
 115       const NetExpr*par = 0;
 116       NetEvent*     eve = 0;
 117
 118       symbol_search(des, scope, path_, sig, mem, par, eve);
 119
 120
 121       if (mem != 0) {
 122             cerr << get_line() << ": error: memories not allowed "
 123                  << "on left side of procedural continuous "
 124                  << "assignment." << endl;
 125             des->errors += 1;
 126             return 0;
 127       }
 128
 129       if (eve != 0) {
 130             cerr << get_line() << ": error: named events not allowed "
 131                  << "on left side of procedural continuous "
 132                  << "assignment." << endl;
 133             des->errors += 1;
 134             return 0;
 135       }
 136
 137       if (sig == 0) {
 138             cerr << get_line() << ": error: reg ``" << path_ << "'' "
 139                  << "is undefined in this scope." << endl;
 140             des->errors += 1;
 141             return 0;
 142       }
 143
 144       switch (sig->type()) {
 145           case NetNet::REG:
 146           case NetNet::IMPLICIT_REG:
 147             break;
 148
 149           default:
 150             cerr << get_line() << ": error: " << path_ << " is not "
 151                  << "a reg in this context." << endl;
 152             des->errors += 1;
 153             return 0;
 154       }
 155
 156       assert(sig);
 157
 158       if (msb_ || lsb_) {
 159
 160             cerr << get_line() << ": error: bit/part selects not allowed "
 161                  << "on left side of procedural continuous assignment."
 162                  << endl;
 163             des->errors += 1;
 164             return 0;
 165       }
 166
 167       return sig;
 168 }
 169
 170 /*
 171  * $Log: elab_anet.cc,v $
 172  * Revision 1.13  2007/03/22 16:08:14  steve
 173  *  Spelling fixes from Larry
 174  *
 175  * Revision 1.12  2006/05/01 20:47:58  steve
 176  *  More explicit datatype setup.
 177  *
 178  * Revision 1.11  2005/07/11 16:56:50  steve
 179  *  Remove NetVariable and ivl_variable_t structures.
 180  *
 181  * Revision 1.10  2004/10/04 01:10:52  steve
 182  *  Clean up spurious trailing white space.
 183  *
 184  * Revision 1.9  2003/09/19 03:50:12  steve
 185  *  Remove find_memory method from Design class.
 186  *
 187  * Revision 1.8  2003/06/21 01:21:43  steve
 188  *  Harmless fixup of warnings.
 189  *
 190  * Revision 1.7  2003/03/06 00:28:41  steve
 191  *  All NetObj objects have lex_string base names.
 192  *
 193  * Revision 1.6  2003/01/27 05:09:17  steve
 194  *  Spelling fixes.
 195  *
 196  * Revision 1.5  2002/08/12 01:34:58  steve
 197  *  conditional ident string using autoconfig.
 198  *
 199  * Revision 1.4  2001/12/03 04:47:14  steve
 200  *  Parser and pform use hierarchical names as hname_t
 201  *  objects instead of encoded strings.
 202  *
 203  * Revision 1.3  2001/07/25 03:10:48  steve
 204  *  Create a config.h.in file to hold all the config
 205  *  junk, and support gcc 3.0. (Stephan Boettcher)
 206  *
 207  * Revision 1.2  2001/01/06 02:29:36  steve
 208  *  Support arrays of integers.
 209  *
 210  * Revision 1.1  2000/12/06 06:31:09  steve
 211  *  Check lvalue of procedural continuous assign (PR#29)
 212  *
 213  */
 214