https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64716
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2015-01-21
CC| |jakub at gcc dot gnu.org
Blocks|53947 |
Ever confirmed|0 |1
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
This is about SLP vectorization, and for some reason we treat the whole bb as
one item to slp vectorize, rather than trying to vectorize just individual
statements where beneficial.
So we end up with:
pr64716.c:2633:12: note: Build SLP failed: unrolling required in basic block
SLP
pr64716.c:2633:12: note: Failed to SLP the basic block.
pr64716.c:2633:12: note: not vectorized: failed to find SLP opportunities in
basic block.
where 2633 in my copy is that r0 = 1./(*vector)[j+3]; line - group_size is 6 on
that stmt and nunits is 4 (for AVX2) or 2 (for 128-bit vectors).
