------- Comment #6 from ebotcazou at gcc dot gnu dot org 2006-09-09 22:09
-------
> it looks like ifcvt messes up in pass 3 and puts the post-inc in the
> cond-exec block.
It's actually the combiner that wrongly ditches the post-inc, at least with
the last set of options you posted. Amazingly enough, on the 4.1 branch, the
combiner is the first pass which deduces that
*((deeper)->buffer_position)++ < 0
is always false. In particular, we have this little gem in t97.final_cleanup
unsigned char * D.1386;
_Bool iftmp.0;
iftmp.0 = (int) *D.1386 < 0;
even at -O2! This is optimized on mainline, which hides the problem there.
Fixing...
--
ebotcazou at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |ebotcazou at gcc dot gnu dot
|dot org |org
Status|NEW |ASSIGNED
Last reconfirmed|2006-08-08 09:09:48 |2006-09-09 22:09:59
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28636
