https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71231
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2016-05-23
CC| |hubicka at gcc dot gnu.org,
| |rguenth at gcc dot gnu.org
Target Milestone|--- |7.0
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed. Last time this was Honzas estimation changes, thus CCing Honza
(aka, I told you so before).
160517.34236301 ... 48.68
160518.25236346 ... -1.00
160519.34236434 ... 155.92
so unfortunately we have one broken run but the above "encodes" the revision
range 236301 (good) to 236434 (bad). The other tester constrais the revision
range to 236299 (good) to 236427 (bad).
It might be the add-to-multiply reassoc which also applies to x + x, producing
2 * x which is eventually vectorized to comparatively very slow code (in case
of integers). There is a regression bug showing we need to fix this in
vectorizer pattern recog.
