luke
/
iverilog
mirror of https://github.com/steveicarus/iverilog.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Handle wide net constants with unary minus.

This commit is contained in:
steve 2001-01-25 02:05:16 +00:00
parent 41242735ed
commit 88a2ca2168
1 changed files with 28 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
elab_net.cc
View File

@ -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
*/ */
#if !defined(WINNT) && !defined(macintosh) #if !defined(WINNT) && !defined(macintosh)
#ident "$Id: elab_net.cc,v 1.60 2001/01/24 02:52:30 steve Exp $" #ident "$Id: elab_net.cc,v 1.61 2001/01/25 02:05:16 steve Exp $"
#endif #endif
# include "PExpr.h" # include "PExpr.h"
@ -1700,6 +1700,30 @@ NetNet* PEUnary::elaborate_net(Design*des, const string&path,
break; break;
} }
NetNet* sig;
NetLogic*gate;
// Handle the special case of a 2's complement of a constant
// value. This can be reduced to a no-op on a precalculated
// result.
if (op_ == '-') do {
verinum*val = expr_->eval_const(des, path);
if (val == 0)
break;
sig = new NetNet(scope, des->local_symbol(path),
NetNet::WIRE, width);
sig->local_flag(true);
verinum tmp(v_not(*val) + verinum(1UL, width), width);
NetConst*con = new NetConst(des->local_symbol(path), tmp);
for (unsigned idx = 0 ; idx < width ; idx += 1)
connect(sig->pin(idx), con->pin(idx));
des->add_node(con);
return sig;
} while (0);
NetNet* sub_sig = expr_->elaborate_net(des, path, owidth, 0, 0, 0); NetNet* sub_sig = expr_->elaborate_net(des, path, owidth, 0, 0, 0);
if (sub_sig == 0) { if (sub_sig == 0) {
des->errors += 1; des->errors += 1;
@ -1707,8 +1731,6 @@ NetNet* PEUnary::elaborate_net(Design*des, const string&path,
} }
assert(sub_sig); assert(sub_sig);
NetNet* sig;
NetLogic*gate;
switch (op_) { switch (op_) {
case '~': // Bitwise NOT case '~': // Bitwise NOT
sig = new NetNet(scope, des->local_symbol(path), NetNet::WIRE, sig = new NetNet(scope, des->local_symbol(path), NetNet::WIRE,
@ -1880,6 +1902,9 @@ NetNet* PEUnary::elaborate_net(Design*des, const string&path,
/* /*
* $Log: elab_net.cc,v $ * $Log: elab_net.cc,v $
* Revision 1.61 2001/01/25 02:05:16 steve
* Handle wide net constants with unary minus.
*
* Revision 1.60 2001/01/24 02:52:30 steve * Revision 1.60 2001/01/24 02:52:30 steve
* Handle some special cases of unary 2's complement, * Handle some special cases of unary 2's complement,
* and improve netlist expression width handling. * and improve netlist expression width handling.