iverilog/vvm/vvm_gates.cc

/*
 * Copyright (c) 1999 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
 *  ---
 *    You should also have recieved a copy of the Picture Elements
 *    Binary Software License offer along with the source. This offer
 *    allows you to obtain the right to redistribute the software in
 *    binary (compiled) form. If you have not received it, contact
 *    Picture Elements, Inc., 777 Panoramic Way, Berkeley, CA 94704.
 */
#if !defined(WINNT) && !defined(macintosh)
#ident "$Id: vvm_gates.cc,v 1.6 2000/02/24 01:56:28 steve Exp $"
#endif

# include  "vvm_gates.h"

vvm_out_event::vvm_out_event(vpip_bit_t v, action_t o)
: output_(o), val_(v)
{
}

vvm_out_event::~vvm_out_event()
{
}

void vvm_out_event::event_function()
{
      output_(val_);
}

vvm_1bit_out::vvm_1bit_out(vvm_out_event::action_t o, unsigned d)
: output_(o), delay_(d)
{
}

vvm_1bit_out::~vvm_1bit_out()
{
}

void vvm_1bit_out::output(vpip_bit_t val)
{
      vvm_event*ev = new vvm_out_event(val, output_);
      ev -> schedule(delay_);
}


vpip_bit_t compute_and(const vpip_bit_t*inp, unsigned count)
{
      vpip_bit_t outval = inp[0];
      for (unsigned i = 1 ;  i < count ;  i += 1)
	    outval = outval & inp[i];
      return outval;
}

vpip_bit_t compute_or(const vpip_bit_t*inp, unsigned count)
{
      vpip_bit_t outval = inp[0];
      for (unsigned i = 1 ;  i < count ;  i += 1)
	    outval = outval | inp[i];
      return outval;
}

vpip_bit_t compute_nor(const vpip_bit_t*inp, unsigned count)
{
      vpip_bit_t outval = inp[0];
      for (unsigned i = 1 ;  i < count ;  i += 1)
	    outval = outval | inp[i];
      return v_not(outval);
}

vpip_bit_t compute_xor(const vpip_bit_t*inp, unsigned count)
{
      vpip_bit_t outval = inp[0];
      for (unsigned i = 1; i < count; i++)
	    outval = outval ^ inp[i];
      return outval;
}

vpip_bit_t compute_nand(const vpip_bit_t*inp, unsigned count)
{
      return v_not(compute_and(inp,count));
}

vpip_bit_t compute_xnor(const vpip_bit_t*inp, unsigned count)
{
      return v_not(compute_xor(inp,count));
}

void compute_mux(vpip_bit_t*out, unsigned wid,
		 const vpip_bit_t*sel, unsigned swid,
		 const vpip_bit_t*dat, unsigned size)
{
      unsigned tmp = 0;
      for (unsigned idx = 0 ;  idx < swid ;  idx += 1)
	    switch (sel[idx]) {
		case V0:
		  break;
		case V1:
		  tmp |= (1<<idx);
		  break;
		default:
		  tmp = size;
		  break;
	    }

      if (tmp >= size) {

	    if (swid > 1) {
		  for (unsigned idx = 0; idx < wid ;  idx += 1)
			out[idx] = Vx;
	    } else {
		  const unsigned b0 = 0;
		  const unsigned b1 = wid;
		  for (unsigned idx = 0 ;  idx < wid ;  idx += 1) {
			if (dat[idx+b0] == dat[idx+b1])
			      out[idx] = dat[idx+b0];
			else
			      out[idx] = Vx;
		  }
	    }

      } else {
	    unsigned b = tmp * wid;
	    for (unsigned idx = 0; idx < wid ;  idx += 1)
		  out[idx] = dat[idx+b];
      }
}


/*
 * $Log: vvm_gates.cc,v $
 * Revision 1.6  2000/02/24 01:56:28  steve
 *  change not to v_not.
 *
 * Revision 1.5  2000/02/23 02:56:56  steve
 *  Macintosh compilers do not support ident.
 *
 * Revision 1.4  1999/12/12 19:47:54  steve
 *  Remove the useless vvm_simulation class.
 *
 * Revision 1.3  1999/12/02 04:54:11  steve
 *  Handle mux sel of X, if inputs are equal.
 *
 * Revision 1.2  1999/11/24 04:38:49  steve
 *  LT and GT fixes from Eric Aardoom.
 *
 * Revision 1.1  1999/11/22 00:30:52  steve
 *  Detemplate some and, or and nor methods.
 *
 */