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Handle condit clauses with unassigned outputs.

This commit is contained in:
steve 2006-06-01 03:01:48 +00:00
parent f942657ad5
commit dde69cebb6
2 changed files with 117 additions and 38 deletions
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12
net_nex_output.cc
View File

@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: net_nex_output.cc,v 1.11.2.5 2006/05/18 01:47:12 steve Exp $"
#ident "$Id: net_nex_output.cc,v 1.11.2.6 2006/06/01 03:01:48 steve Exp $"
#endif
# include "config.h"
@ -114,11 +114,12 @@ void NetBlock::nex_output(NexusSet&out)
if (last_ == 0)
return;
NetProc*cur = last_;
NetProc*cur = last_->next_;
NexusSet accum;
do {
cur = cur->next_;
cur->nex_output(out);
} while (cur != last_);
cur = cur->next_;
} while (cur != last_->next_);
}
void NetCase::nex_output(NexusSet&out)
@ -167,6 +168,9 @@ void NetWhile::nex_output(NexusSet&out)
/*
* $Log: net_nex_output.cc,v $
* Revision 1.11.2.6 2006/06/01 03:01:48 steve
* Handle condit clauses with unassigned outputs.
*
* Revision 1.11.2.5 2006/05/18 01:47:12 steve
* Fix synthesis of l-value bit select in block.
*

143
synth2.cc
View File

@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CVS_IDENT
#ident "$Id: synth2.cc,v 1.39.2.32 2006/05/20 16:06:48 steve Exp $"
#ident "$Id: synth2.cc,v 1.39.2.33 2006/06/01 03:01:48 steve Exp $"
#endif
# include "config.h"
@ -766,6 +766,7 @@ bool NetCase::synth_async_1hot_(Design*des, NetScope*scope, bool sync_flag,
return true;
}
/*
* Handle synthesis for an asynchronous condition statement. If we get
* here, we know that the CE of a DFF has already been filled, so the
@ -871,55 +872,126 @@ bool NetCondit::synth_async(Design*des, NetScope*scope, bool sync_flag,
}
}
unsigned mux_width = 0;
/* Figure out how many mux bits we are going to need. */
for (unsigned idx = 0 ; idx < nex_out->pin_count(); idx += 1) {
if (accum->pin(idx).is_linked() || sync_flag) {
mux_width += 1;
continue;
}
if (asig->pin(idx).is_linked() && bsig->pin(idx).is_linked()) {
mux_width += 1;
continue;
}
}
/* Create a mux and hook it up. */
NetMux*mux = new NetMux(scope, scope->local_symbol(),
nex_out->pin_count(), 2, 1);
mux_width, 2, 1);
mux->set_line(*this);
connect(mux->pin_Sel(0), ssig->pin(0));
bool return_flag = true;
/* Connected the clauses to the data inputs of the
condition. If there are bits unassigned by the case, then
bind them from the accum bits instead. If the bit is not
represented in the accum list, but this is a synchronous
output, then get the bit from the nex_map, which is the
output held in the DFF. */
for (unsigned idx = 0 ; idx < asig->pin_count() ; idx += 1) {
mux_width = 0;
for (unsigned idx = 0 ; idx < nex_out->pin_count() ; idx += 1) {
int flag = 0;
if (asig->pin(idx).is_linked())
connect(mux->pin_Data(idx, 1), asig->pin(idx));
else if (accum->pin(idx).is_linked())
connect(mux->pin_Data(idx, 1), accum->pin(idx));
else if (sync_flag)
connect(mux->pin_Data(idx, 1), nex_map->pin(idx));
else {
cerr << get_line()
<< ": error: Condition true clause "
<< "does not assign expected outputs." << endl;
des->errors += 1;
return_flag = false;
}
}
for (unsigned idx = 0 ; idx < bsig->pin_count() ; idx += 1) {
flag |= 0100;
if (bsig->pin(idx).is_linked())
connect(mux->pin_Data(idx, 0), bsig->pin(idx));
else if (accum->pin(idx).is_linked())
connect(mux->pin_Data(idx, 0), accum->pin(idx));
else if (sync_flag)
connect(mux->pin_Data(idx, 0), nex_map->pin(idx));
else {
cerr << get_line()
<< ": error: Condition false clause "
<< "does not assign expected outputs." << endl;
des->errors += 1;
return_flag = false;
flag |= 0010;
if (accum->pin(idx).is_linked())
flag |= 0001;
switch (flag) {
case 0111:
case 0110:
connect(mux->pin_Data(mux_width, 1), asig->pin(idx));
connect(mux->pin_Data(mux_width, 0), bsig->pin(idx));
connect(nex_out->pin(idx), mux->pin_Result(mux_width));
mux_width += 1;
break;
case 0101:
connect(mux->pin_Data(mux_width, 1), asig->pin(idx));
connect(mux->pin_Data(mux_width, 0), accum->pin(idx));
connect(nex_out->pin(idx), mux->pin_Result(mux_width));
mux_width += 1;
break;
case 0100:
if (sync_flag) {
connect(mux->pin_Data(mux_width, 1), asig->pin(idx));
connect(mux->pin_Data(mux_width, 0),nex_map->pin(idx));
connect(nex_out->pin(idx), mux->pin_Result(mux_width));
mux_width += 1;
} else {
#if 0
cerr << get_line()
<< ": error: Condition false clause "
<< "does not assign expected outputs." << endl;
des->errors += 1;
return_flag = false;
#else
/* This should check that bsig is latched by
the condition select or is used
internally by the false clause. but since
there is no latch support, assume it is
used internally. */
connect(nex_out->pin(idx), asig->pin(idx));
#endif
}
break;
case 0011:
connect(mux->pin_Data(mux_width, 1), accum->pin(idx));
connect(mux->pin_Data(mux_width, 0), bsig->pin(idx));
connect(nex_out->pin(idx), mux->pin_Result(mux_width));
mux_width += 1;
break;
case 0010:
if (sync_flag) {
connect(mux->pin_Data(mux_width, 1),nex_map->pin(idx));
connect(mux->pin_Data(mux_width, 0), bsig->pin(idx));
connect(nex_out->pin(idx), mux->pin_Result(mux_width));
mux_width += 1;
} else {
#if 0
cerr << get_line()
<< ": error: Condition true clause "
<< "does not assign expected outputs." << endl;
des->errors += 1;
return_flag = false;
#else
/* This should check that bsig is latched by
the condition select or is used
internally by the false clause. but since
there is no latch support, assume it is
used internally. */
connect(nex_out->pin(idx), bsig->pin(idx));
#endif
}
break;
case 0001:
connect(mux->pin_Data(mux_width, 1), accum->pin(idx));
connect(mux->pin_Data(mux_width, 0), accum->pin(idx));
connect(nex_out->pin(idx), mux->pin_Result(mux_width));
mux_width += 1;
break;
case 0000:
assert(0);
break;
default:
assert(0);
break;
}
}
for (unsigned idx = 0 ; idx < mux->width() ; idx += 1)
connect(nex_out->pin(idx), mux->pin_Result(idx));
assert(mux_width == mux->width());
des->add_node(mux);
@ -1854,6 +1926,9 @@ void synth2(Design*des)
/*
* $Log: synth2.cc,v $
* Revision 1.39.2.33 2006/06/01 03:01:48 steve
* Handle condit clauses with unassigned outputs.
*
* Revision 1.39.2.32 2006/05/20 16:06:48 steve
* Replace assertions with error messages.
*