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Watch out for signed constants in magnitude compare.

This commit is contained in:
steve 2005-06-17 05:05:53 +00:00
parent 4cc421b3b7
commit a79fee39e9
1 changed files with 19 additions and 9 deletions
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18
eval_tree.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: eval_tree.cc,v 1.62 2004/10/04 01:10:53 steve Exp $" #ident "$Id: eval_tree.cc,v 1.63 2005/06/17 05:05:53 steve Exp $"
#endif #endif
# include "config.h" # include "config.h"
@ -224,20 +224,27 @@ NetEConst* NetEBComp::eval_less_()
return new NetEConst(result); return new NetEConst(result);
} }
/* Detect the case where the right side is greater that or
/* Detect the case where the right side is greater than or
equal to the largest value the left side can possibly equal to the largest value the left side can possibly
have. */ have. Use the width of the left expression as all 1's to
calculate the maximum possible width for the left_
expression. This test only works of the compare is
unsigned. */
if (! (rv.has_sign() || left_->has_sign())) {
assert(left_->expr_width() > 0); assert(left_->expr_width() > 0);
verinum lv (verinum::V1, left_->expr_width()); verinum lv (verinum::V1, left_->expr_width());
if (lv < rv) { if (lv < rv) {
verinum result(verinum::V1, 1); verinum result(verinum::V1, 1);
return new NetEConst(result); return new NetEConst(result);
} }
}
/* Now go on to the normal test of the values. */ /* Now go on to the normal test of the values. */
NetEConst*l = dynamic_cast<NetEConst*>(left_); NetEConst*l = dynamic_cast<NetEConst*>(left_);
if (l == 0) return 0; if (l == 0) return 0;
lv = l->value(); verinum lv = l->value();
if (! lv.is_defined()) { if (! lv.is_defined()) {
verinum result(verinum::Vx, 1); verinum result(verinum::Vx, 1);
return new NetEConst(result); return new NetEConst(result);
@ -1551,6 +1558,9 @@ NetEConst* NetEUReduce::eval_tree()
/* /*
* $Log: eval_tree.cc,v $ * $Log: eval_tree.cc,v $
* Revision 1.63 2005/06/17 05:05:53 steve
* Watch out for signed constants in magnitude compare.
*
* Revision 1.62 2004/10/04 01:10:53 steve * Revision 1.62 2004/10/04 01:10:53 steve
* Clean up spurious trailing white space. * Clean up spurious trailing white space.
* *