https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86132
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |missed-optimization
Status|UNCONFIRMED |NEW
Last reconfirmed| |2018-06-14
CC| |hubicka at gcc dot gnu.org,
| |marxin at gcc dot gnu.org,
| |rguenth at gcc dot gnu.org
Component|middle-end |ipa
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I see calls to want_foo () which can clobber 'object':
<bb 3> [local count: 187153200]:
_8 = single_slow ();
object = _8;
<bb 4> [local count: 1073741824]:
# prephitmp_16 = PHI <_8(3), object.1_7(2)>
want_foo (prephitmp_16);
object.1_4 = object;
if (object.1_4 == 0B)
goto <bb 5>; [17.43%]
else
goto <bb 6>; [82.57%]
that's the first issue we hit. Then I would expect jump threading to
eventually optimize this. I'm not sure returns_nonnull is handled
in the required places in optimizers though.
I'm not sure why IPA reference doesn't do its job here, it seems to be
confused by inlining?
