https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64396
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Target Milestone|--- |9.0
Resolution|--- |FIXED
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This is fixed in GCC 9+ on the rtl level due to gimple level changes. GCC 10+
late FRE (which was added by r10-1420) can detect it and remove the redudancy.
The GCC 9 change was due to this:
_25 = _24 /[ex] 4;
_27 = _25 + 1;
_28 = _27 * 4;
Being transformed into just:
_28 = _24 + 4;
Which was due to r9-3247.
So fixed in GCC 9 with it fully fixed in GCC 10.
