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Elaborate unary subtract and NOT in netlist 

contexts, and concatenation too.
This commit is contained in:
steve 2005-01-30 05:20:38 +00:00
parent 68a788221e
commit 20be0351ae
1 changed files with 72 additions and 54 deletions
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126
elab_net.cc
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@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: elab_net.cc,v 1.148 2005/01/29 18:46:18 steve Exp $"
#ident "$Id: elab_net.cc,v 1.149 2005/01/30 05:20:38 steve Exp $"
#endif
# include "config.h"
@ -1258,10 +1258,13 @@ NetNet* PEConcat::elaborate_net(Design*des, NetScope*scope,
Link::strength_t drive1) const
{
svector<NetNet*>nets (parms_.count());
unsigned pins = 0;
unsigned vector_width = 0;
unsigned errors = 0;
unsigned repeat = 1;
/* The repeat expression must evaluate to a compile-time
constant. This is used to generate the width of the
concatenation. */
if (repeat_) {
NetExpr*etmp = elab_and_eval(des, scope, repeat_);
assert(etmp);
@ -1286,6 +1289,11 @@ NetNet* PEConcat::elaborate_net(Design*des, NetScope*scope,
}
}
if (debug_elaborate) {
cerr << get_line() <<": debug: PEConcat concat repeat="
<< repeat << "." << endl;
}
/* The operands of the concatenation must contain all
self-determined arguments. Set this flag to force an error
message if this is not the case. */
@ -1321,7 +1329,7 @@ NetNet* PEConcat::elaborate_net(Design*des, NetScope*scope,
if (nets[idx] == 0)
errors += 1;
else
pins += nets[idx]->pin_count();
vector_width += nets[idx]->vector_width();
}
must_be_self_determined_flag = save_flag;
@ -1336,6 +1344,18 @@ NetNet* PEConcat::elaborate_net(Design*des, NetScope*scope,
return 0;
}
if (debug_elaborate) {
cerr << get_line() <<": debug: PEConcat concat collected "
<< "width=" << vector_width << ", repeat=" << repeat
<< " of " << nets.count() << " expressions." << endl;
}
NetConcat*dev = new NetConcat(scope, scope->local_symbol(),
vector_width*repeat,
nets.count()*repeat);
dev->set_line(*this);
des->add_node(dev);
/* Make the temporary signal that connects to all the
operands, and connect it up. Scan the operands of the
concat operator from least significant to most significant,
@ -1345,17 +1365,18 @@ NetNet* PEConcat::elaborate_net(Design*des, NetScope*scope,
connect loop as many times as necessary. */
NetNet*osig = new NetNet(scope, scope->local_symbol(),
NetNet::IMPLICIT, pins * repeat);
NetNet::IMPLICIT, vector_width * repeat);
pins = 0;
for (unsigned rpt = 0 ; rpt < repeat ; rpt += 1)
for (unsigned idx = nets.count() ; idx > 0 ; idx -= 1) {
NetNet*cur = nets[idx-1];
for (unsigned pin = 0; pin < cur->pin_count(); pin += 1) {
connect(osig->pin(pins), cur->pin(pin));
pins += 1;
}
connect(dev->pin(0), osig->pin(0));
unsigned cur_pin = 1;
for (unsigned rpt = 0; rpt < repeat ; rpt += 1) {
for (unsigned idx = 0 ; idx < nets.count() ; idx += 1) {
NetNet*cur = nets[nets.count()-idx-1];
connect(dev->pin(cur_pin++), cur->pin(0));
}
}
osig->local_flag(true);
return osig;
@ -2289,6 +2310,9 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
// value. This can be reduced to a no-op on a precalculated
// result.
if (op_ == '-') do {
// TODO: Should replace this with a call to
// elab_and_eval. Possibly blend this with the rest of
// the elaboration as well.
verinum*val = expr_->eval_const(des, scope);
if (val == 0)
break;
@ -2303,15 +2327,23 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
/* Take the 2s complement by taking the 1s complement
and adding 1. */
verinum tmp (v_not(*val));
verinum tmp (v_not(*val), width);
verinum one (1UL, width);
tmp = tmp + one;
NetConst*con = new NetConst(scope, scope->local_symbol(), tmp);
for (unsigned idx = 0 ; idx < width ; idx += 1)
connect(sig->pin(idx), con->pin(idx));
tmp = verinum(tmp + one, width);
tmp.has_sign(val->has_sign());
NetConst*con = new NetConst(scope, scope->local_symbol(), tmp);
connect(sig->pin(0), con->pin(0));
if (debug_elaborate) {
cerr << get_line() << ": debug: Replace expression "
<< *this << " with constant " << tmp << "."<<endl;
}
delete val;
des->add_node(con);
return sig;
} while (0);
NetNet* sub_sig = expr_->elaborate_net(des, scope, owidth, 0, 0, 0);
@ -2327,18 +2359,18 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
switch (op_) {
case '~': // Bitwise NOT
sig = new NetNet(scope, scope->local_symbol(), NetNet::WIRE,
sub_sig->pin_count());
sub_sig->vector_width());
sig->local_flag(true);
for (unsigned idx = 0 ; idx < sub_sig->pin_count() ; idx += 1) {
gate = new NetLogic(scope, scope->local_symbol(),
2, NetLogic::NOT, 1);
connect(gate->pin(1), sub_sig->pin(idx));
connect(gate->pin(0), sig->pin(idx));
des->add_node(gate);
gate->rise_time(rise);
gate->fall_time(fall);
gate->decay_time(decay);
}
gate = new NetLogic(scope, scope->local_symbol(),
2, NetLogic::NOT, sub_sig->vector_width());
gate->set_line(*this);
des->add_node(gate);
gate->rise_time(rise);
gate->fall_time(fall);
gate->decay_time(decay);
connect(gate->pin(1), sub_sig->pin(0));
connect(gate->pin(0), sig->pin(0));
break;
case 'N': // Reduction NOR
@ -2360,10 +2392,10 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
NetNet::WIRE, owidth);
sig->local_flag(true);
if (sub_sig->pin_count() < owidth)
if (sub_sig->vector_width() < owidth)
sub_sig = pad_to_width(des, sub_sig, owidth);
switch (sub_sig->pin_count()) {
switch (sub_sig->vector_width()) {
case 0:
assert(0);
break;
@ -2379,31 +2411,11 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
gate->decay_time(decay);
break;
case 2:
gate = new NetLogic(scope, scope->local_symbol(),
2, NetLogic::BUF, 1);
connect(gate->pin(0), sig->pin(0));
connect(gate->pin(1), sub_sig->pin(0));
des->add_node(gate);
gate->rise_time(rise);
gate->fall_time(fall);
gate->decay_time(decay);
gate = new NetLogic(scope, scope->local_symbol(),
3, NetLogic::XOR, 1);
connect(gate->pin(0), sig->pin(1));
connect(gate->pin(1), sub_sig->pin(0));
connect(gate->pin(2), sub_sig->pin(1));
des->add_node(gate);
gate->rise_time(rise);
gate->fall_time(fall);
gate->decay_time(decay);
break;
default:
NetAddSub*sub = new NetAddSub(scope, scope->local_symbol(),
sig->pin_count());
sub->attribute(perm_string::literal("LPM_Direction"), verinum("SUB"));
sig->vector_width());
sub->attribute(perm_string::literal("LPM_Direction"),
verinum("SUB"));
des->add_node(sub);
@ -2418,7 +2430,7 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
NetNet*tmp_sig = new NetNet(scope, scope->local_symbol(),
NetNet::WIRE,
sub_sig->pin_count());
sub_sig->vector_width());
tmp_sig->local_flag(true);
connect(tmp_sig->pin(0), sub->pin_DataA());
@ -2432,6 +2444,8 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
sig = 0;
}
if (reduction) {
cerr << get_line()
<< ": XXXX: PEUnary::elab_net reductions not complete." << endl;
sig = new NetNet(scope, scope->local_symbol(), NetNet::WIRE);
sig->local_flag(true);
gate = new NetLogic(scope, scope->local_symbol(),
@ -2451,6 +2465,10 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
/*
* $Log: elab_net.cc,v $
* Revision 1.149 2005/01/30 05:20:38 steve
* Elaborate unary subtract and NOT in netlist
* contexts, and concatenation too.
*
* Revision 1.148 2005/01/29 18:46:18 steve
* Netlist boolean expressions generate gate vectors.
*