https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103723
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Summary|zero extend not moved out |zero extend not sunk out of
|of the loop after IV-OPTS |the loop after IV-OPTS in
| |the sink pass
--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note there's pass_sink_code after IVOPTs which is what is designed to perform
sinking. That is probably confused by seeing
<bb 5> [local count: 1014686026]:
# ivtmp.7_15 = PHI <ivtmp.7_7(7), 2(3)>
_4 = (unsigned int) ivtmp.7_15;
_3 = MEM[(const uint8_t *)buf_9(D) + ivtmp.7_15 * 1];
_6 = MEM[(const uint8_t *)buf_back_11(D) + ivtmp.7_15 * 1];
if (_3 == _6)
goto <bb 4>; [94.50%]
else
goto <bb 10>; [5.50%]
<bb 10> [local count: 55807731]:
<bb 6> [local count: 114863531]:
# len_test_14 = PHI <len_test_12(9), _4(10), 2(8)>
return len_test_14;
where it doesn't consider inserting on edges because usually the pred works
fine but here it's a no-op sink and splitting the edge might be profitable
because its a loop exit.
So the sinking pass needs tweaking for such case (but _not_ split the edge
in case the PHI use is on a simple merge)
