[Bug tree-optimization/77895] Unaligned movdqa generated by GCC 6.2.0 with -O3

rguenth at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Fri Oct 7 10:23:00 GMT 2016


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77895

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
                       *((unsigned int*)dst) = *((unsigned int*)src);

this requires dst and src to be aligned as 'unsigned int'.  Thus vectorization
will peel until it reaches alignment (which it can't for your 1-byte aligned
src/dst).


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