iverilog/net_nex_input.cc

/*
 * Copyright (c) 2002 Stephen Williams (steve@icarus.com)
 *
 *    This source code is free software; you can redistribute it
 *    and/or modify it in source code form under the terms of the GNU
 *    General Public License as published by the Free Software
 *    Foundation; either version 2 of the License, or (at your option)
 *    any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 */
#if !defined(WINNT)
#ident "$Id: net_nex_input.cc,v 1.4 2002/07/14 23:47:58 steve Exp $"
#endif

# include "config.h"

# include <iostream>

# include  <cassert>
# include  <typeinfo>
# include  "netlist.h"
# include  "netmisc.h"

NexusSet* NetExpr::nex_input()
{
      cerr << get_line()
	   << ": internal error: nex_input not implemented: "
	   << *this << endl;
      return 0;
}

NexusSet* NetProc::nex_input()
{
      cerr << get_line()
	   << ": internal error: NetProc::nex_input not implemented"
	   << endl;
      return 0;
}

NexusSet* NetEBinary::nex_input()
{
      NexusSet*result = left_->nex_input();
      NexusSet*tmp = right_->nex_input();
      result->add(*tmp);
      delete tmp;
      return result;
}

NexusSet* NetEBitSel::nex_input()
{
      NexusSet*result = sig_->nex_input();
      NexusSet*tmp = idx_->nex_input();
      result->add(*tmp);
      delete tmp;
      return result;
}

NexusSet* NetEConcat::nex_input()
{
      NexusSet*result = parms_[0]->nex_input();
      for (unsigned idx = 1 ;  idx < parms_.count() ;  idx += 1) {
	    NexusSet*tmp = parms_[idx]->nex_input();
	    result->add(*tmp);
	    delete tmp;
      }
      return result;
}

/*
 * A constant has not inputs, so always return an empty set.
 */
NexusSet* NetEConst::nex_input()
{
      return new NexusSet;
}

NexusSet* NetEMemory::nex_input()
{
      NexusSet*result = idx_->nex_input();
      return result;
}

/*
 * A parameter by definition has no inputs. It represents a constant
 * value, even if that value is a constant expression.
 */
NexusSet* NetEParam::nex_input()
{
      return new NexusSet;
}

NexusSet* NetEScope::nex_input()
{
      return new NexusSet;
}

NexusSet* NetESelect::nex_input()
{
      NexusSet*result = base_->nex_input();
      NexusSet*tmp = expr_->nex_input();
      result->add(*tmp);
      delete tmp;
      return result;
}

NexusSet* NetESFunc::nex_input()
{
      if (nparms_ == 0)
	    return new NexusSet;

      NexusSet*result = parms_[0]->nex_input();
      for (unsigned idx = 1 ;  idx < nparms_ ;  idx += 1) {
	    NexusSet*tmp = parms_[idx]->nex_input();
	    result->add(*tmp);
	    delete tmp;
      }
      return result;
}

NexusSet* NetESignal::nex_input()
{
      NexusSet*result = new NexusSet;
      for (unsigned idx = 0 ;  idx < net_->pin_count() ;  idx += 1)
	    result->add(net_->pin(idx).nexus());

      return result;
}

NexusSet* NetETernary::nex_input()
{
      NexusSet*tmp;
      NexusSet*result = cond_->nex_input();

      tmp = true_val_->nex_input();
      result->add(*tmp);
      delete tmp;

      tmp = false_val_->nex_input();
      result->add(*tmp);
      delete tmp;

      return result;
}

NexusSet* NetEUFunc::nex_input()
{
      NexusSet*result = new NexusSet;
      for (unsigned idx = 0 ;  idx < parms_.count() ;  idx += 1) {
	    NexusSet*tmp = parms_[idx]->nex_input();
	    result->add(*tmp);
	    delete tmp;
      }

      return result;
}

NexusSet* NetEUnary::nex_input()
{
      return expr_->nex_input();
}

NexusSet* NetAssignBase::nex_input()
{
      NexusSet*result = rval_->nex_input();
      return result;
}

NexusSet* NetBlock::nex_input()
{
      if (last_ == 0)
	    return new NexusSet;

      NetProc*cur = last_;
      NexusSet*result = cur->nex_input();
      cur = cur->next_;
      while (cur != last_) {
	    NexusSet*tmp = cur->nex_input();
	    result->add(*tmp);
	    delete tmp;
	    cur = cur->next_;
      }

      return result;
}

/*
 * The inputs to a case statement are the inputs to the expression,
 * the inputs to all the guards, and the inputs to all the guarded
 * statements.
 */
NexusSet* NetCase::nex_input()
{
      NexusSet*result = expr_->nex_input();
      if (result == 0)
	    return 0;

      for (unsigned idx = 0 ;  idx < nitems_ ;  idx += 1) {

	    assert(items_[idx].statement);
	    NexusSet*tmp = items_[idx].statement->nex_input();
	    assert(tmp);
	    result->add(*tmp);
	    delete tmp;

	    assert(items_[idx].guard);
	    tmp = items_[idx].guard->nex_input();
	    assert(tmp);
	    result->add(*tmp);
	    delete tmp;
      }

      return result;
}

NexusSet* NetCAssign::nex_input()
{
      cerr << get_line() << ": internal warning: NetCAssign::nex_input()"
	   << " not implemented." << endl;
      return new NexusSet;
}

NexusSet* NetCondit::nex_input()
{
      NexusSet*result = expr_->nex_input();
      if (if_ != 0) {
	    NexusSet*tmp = if_->nex_input();
	    result->add(*tmp);
	    delete tmp;
      }

      if (else_ != 0) {
	    NexusSet*tmp = else_->nex_input();
	    result->add(*tmp);
	    delete tmp;
      }

      return result;
}

NexusSet* NetForce::nex_input()
{
      cerr << get_line() << ": internal warning: NetForce::nex_input()"
	   << " not implemented." << endl;
      return new NexusSet;
}

NexusSet* NetForever::nex_input()
{
      NexusSet*result = statement_->nex_input();
      return result;
}

/*
 * The NetPDelay statement is a statement of the form
 *
 *   #<expr> <statement>
 *
 * The nex_input set is the input set of the <statement>. Do *not*
 * include the input set of the <expr> because it does not affect the
 * result.
 */
NexusSet* NetPDelay::nex_input()
{
      NexusSet*result = statement_->nex_input();
      return result;
}

NexusSet* NetRepeat::nex_input()
{
      NexusSet*result = statement_->nex_input();
      NexusSet*tmp = expr_->nex_input();
      result->add(*tmp);
      delete tmp;
      return result;
}

NexusSet* NetSTask::nex_input()
{
      if (parms_.count() == 0)
	    return new NexusSet;

      NexusSet*result = parms_[0]->nex_input();
      for (unsigned idx = 1 ;  idx < parms_.count() ;  idx += 1) {
	    NexusSet*tmp = parms_[idx]->nex_input();
	    result->add(*tmp);
	    delete tmp;
      }

      return result;
}

/*
 * The NetUTask represents a call to a user defined task. There are no
 * parameters to consider, because the compiler already removed them
 * and converted them to blocking assignments.
 */
NexusSet* NetUTask::nex_input()
{
      return new NexusSet;
}

NexusSet* NetWhile::nex_input()
{
      NexusSet*result = proc_->nex_input();
      NexusSet*tmp = cond_->nex_input();
      result->add(*tmp);
      delete tmp;
      return result;
}

/*
 * $Log: net_nex_input.cc,v $
 * Revision 1.4  2002/07/14 23:47:58  steve
 *  Infinite loop in nex_input of NetBlock objects.
 *
 * Revision 1.3  2002/06/05 03:44:25  steve
 *  Add support for memory words in l-value of
 *  non-blocking assignments, and remove the special
 *  NetAssignMem_ and NetAssignMemNB classes.
 *
 * Revision 1.2  2002/04/21 17:43:12  steve
 *  implement nex_input for behavioral statements.
 *
 * Revision 1.1  2002/04/21 04:59:08  steve
 *  Add support for conbinational events by finding
 *  the inputs to expressions and some statements.
 *  Get case and assignment statements working.
 *
 */