Mans Rullgard mans.rullgard@linaro.org wrote on 11.06.2012 19:23:53:
On 11 June 2012 17:34, Ulrich Weigand Ulrich.Weigand@de.ibm.com wrote:
There's a number of issues with how GCC choses the vectorize this loop that we can potentially improve upon. However, it would appear that no matter what, it probably isn't actually helpful to try to vectorize
this
loop in the first place.
It could be beneficial to merge the stores into a single 64-bit store.
Right, I guess this could still be done by SLP even if the loop isn't vectorized ...
However for now, I'd recommend you use -fvect-cost-model when testing the vectorizer on libav.
I'll add that flag and see what happens. Any other flags I should be
using?
I can't think of anything else right now ...
Mit freundlichen Gruessen / Best Regards
Ulrich Weigand
-- Dr. Ulrich Weigand | Phone: +49-7031/16-3727 STSM, GNU compiler and toolchain for Linux on System z and Cell/B.E. IBM Deutschland Research & Development GmbH Vorsitzende des Aufsichtsrats: Martina Koederitz | Geschäftsführung: Dirk Wittkopp Sitz der Gesellschaft: Böblingen | Registergericht: Amtsgericht Stuttgart, HRB 243294