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Fix broken calcuation of NE for constant.

This commit is contained in:
steve 2004-06-22 18:41:48 +00:00
parent 76c0fe459c
commit 69cfdbdc54
1 changed files with 17 additions and 5 deletions
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22
elab_net.cc
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@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/ */
#ifdef HAVE_CVS_IDENT #ifdef HAVE_CVS_IDENT
#ident "$Id: elab_net.cc,v 1.130 2004/06/18 16:38:22 steve Exp $" #ident "$Id: elab_net.cc,v 1.131 2004/06/22 18:41:48 steve Exp $"
#endif #endif
# include "config.h" # include "config.h"
@ -455,6 +455,13 @@ static NetNet* compare_eq_constant(Design*des, NetScope*scope,
ones += 1; ones += 1;
} }
/* Now make reduction logic to test that all the 1 bits are 1,
and all the 0 bits are 0. The results will be ANDed
together later, if needed. NOTE that if the compare is !=,
and we know that we will not need an AND later, then fold
the final invert into the reduction gate to get the right
sense of the output. If we do need the AND later, then we
will put the invert on that instead. */
NetLogic*zero_gate = 0; NetLogic*zero_gate = 0;
NetLogic*ones_gate = 0; NetLogic*ones_gate = 0;
if (zeros > 0 && op_code == 'e') if (zeros > 0 && op_code == 'e')
@ -462,13 +469,15 @@ static NetNet* compare_eq_constant(Design*des, NetScope*scope,
zeros + 1, NetLogic::NOR); zeros + 1, NetLogic::NOR);
if (zeros > 0 && op_code == 'n') if (zeros > 0 && op_code == 'n')
zero_gate = new NetLogic(scope, scope->local_symbol(), zero_gate = new NetLogic(scope, scope->local_symbol(),
zeros + 1, NetLogic::OR); zeros + 1,
ones > 0? NetLogic::NOR : NetLogic::OR);
if (ones > 0 && op_code == 'e') if (ones > 0 && op_code == 'e')
ones_gate = new NetLogic(scope, scope->local_symbol(), ones_gate = new NetLogic(scope, scope->local_symbol(),
ones + 1, NetLogic::AND); ones + 1, NetLogic::AND);
if (ones > 0 && op_code == 'n') if (ones > 0 && op_code == 'n')
ones_gate = new NetLogic(scope, scope->local_symbol(), ones_gate = new NetLogic(scope, scope->local_symbol(),
ones + 1, NetLogic::NAND); ones + 1,
zeros > 0? NetLogic::AND : NetLogic::NAND);
unsigned zidx = 0; unsigned zidx = 0;
unsigned oidx = 0; unsigned oidx = 0;
@ -494,8 +503,8 @@ static NetNet* compare_eq_constant(Design*des, NetScope*scope,
connect(and_sig->pin(0), zero_gate->pin(0)); connect(and_sig->pin(0), zero_gate->pin(0));
connect(and_sig->pin(1), ones_gate->pin(0)); connect(and_sig->pin(1), ones_gate->pin(0));
NetLogic*and_gate = new NetLogic(scope, NetLogic*and_gate = new NetLogic(scope,
scope->local_symbol(), scope->local_symbol(), 3,
3, NetLogic::AND); op_code == 'n'? NetLogic::NAND : NetLogic::AND);
connect(and_gate->pin(0), osig->pin(0)); connect(and_gate->pin(0), osig->pin(0));
connect(and_gate->pin(1), and_sig->pin(0)); connect(and_gate->pin(1), and_sig->pin(0));
connect(and_gate->pin(2), and_sig->pin(1)); connect(and_gate->pin(2), and_sig->pin(1));
@ -2595,6 +2604,9 @@ NetNet* PEUnary::elaborate_net(Design*des, NetScope*scope,
/* /*
* $Log: elab_net.cc,v $ * $Log: elab_net.cc,v $
* Revision 1.131 2004/06/22 18:41:48 steve
* Fix broken calcuation of NE for constant.
*
* Revision 1.130 2004/06/18 16:38:22 steve * Revision 1.130 2004/06/18 16:38:22 steve
* compare-to-constant uses sig len, not val len. * compare-to-constant uses sig len, not val len.
* *