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Account for negatives in cmp/s

This commit is contained in:
steve 2001-12-31 00:01:16 +00:00
parent 03aebd7525
commit a3fe753826
1 changed files with 30 additions and 3 deletions
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33
vvp/vthread.cc
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@ -17,7 +17,7 @@
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#if !defined(WINNT)
#ident "$Id: vthread.cc,v 1.64 2001/11/06 03:07:22 steve Exp $"
#ident "$Id: vthread.cc,v 1.65 2001/12/31 00:01:16 steve Exp $"
#endif
# include "vthread.h"
@ -420,8 +420,11 @@ bool of_CMPS(vthread_t thr, vvp_code_t cp)
unsigned idx1 = cp->bit_idx[0];
unsigned idx2 = cp->bit_idx[1];
unsigned sig1 = thr_get_bit(thr, idx1 + cp->number - 1);
unsigned sig2 = thr_get_bit(thr, idx2 + cp->number - 1);
unsigned end1 = (idx1 < 4)? idx1 : idx1 + cp->number - 1;
unsigned end2 = (idx2 < 4)? idx2 : idx2 + cp->number - 1;
unsigned sig1 = thr_get_bit(thr, end1);
unsigned sig2 = thr_get_bit(thr, end2);
for (unsigned idx = 0 ; idx < cp->number ; idx += 1) {
unsigned lv = thr_get_bit(thr, idx1);
@ -454,6 +457,27 @@ bool of_CMPS(vthread_t thr, vvp_code_t cp)
else if ((sig1 == 0) && (sig2 == 1))
lt = 0;
/* Correct the lt bit to account for the sign of the parameters. */
if (lt < 2) {
sig1 = thr_get_bit(thr, end1);
sig2 = thr_get_bit(thr, end2);
/* If both numbers are negative, then switch the
direction of the lt. */
if ((sig1 == 1) && (sig2 == 1) && (eq != 0))
lt ^= 1;
/* If the first is negative and the last positive, then
a < b for certain. */
if ((sig1 == 1) && (sig2 == 0))
lt = 1;
/* If the first is positive and the last negative, then
a > b for certain. */
if ((sig1 == 0) && (sig2 == 1))
lt = 0;
}
thr_put_bit(thr, 4, eq);
thr_put_bit(thr, 5, lt);
thr_put_bit(thr, 6, eeq);
@ -1672,6 +1696,9 @@ bool of_ZOMBIE(vthread_t thr, vvp_code_t)
/*
* $Log: vthread.cc,v $
* Revision 1.65 2001/12/31 00:01:16 steve
* Account for negatives in cmp/s
*
* Revision 1.64 2001/11/06 03:07:22 steve
* Code rearrange. (Stephan Boettcher)
*