http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54733
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |missed-optimization
Status|UNCONFIRMED |NEW
Last reconfirmed| |2012-09-28
Ever Confirmed|0 |1
--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-09-28
10:47:44 UTC ---
Confirmed. The original idea was to leverage the byte-swap pass for this.
First you need to extend that to work on a memory source (which it currently
does not handle), then you, in addition to detecting bswap, emit a word
load and detect the "noop" pattern which then skips bswap. (the byte-swap
pass was also supposed to utilize the vector shuffle engine for non-bswap
shuffles).
