https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67681
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2016-03-10
Ever confirmed|0 |1
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
I suppose adjusting expression_expensive slightly might be workable, not sure.
SCCP does aggressively replace all final values that are "not expensive"
even if that doesn't yield in any followup transforms (so we eventually
compute things twice for no good reason). IMHO SCCP should be re-written
as a "tool" to passes can force the transform if it is necessary for them
(and profitable, say for IVOPTs). One can do this "rewrite" by splitting
analysis, cost compute and transform so that for example the vectorizer
could handle things by providing a different cost analysis and forcing
the transform if vectorization is otherwise possible.
