------- Comment #2 from rguenth at gcc dot gnu dot org 2008-08-18 15:55 -------
Note that there is no loop left on the trunk for the testcase, but after
the vectorizer it is all unrolled completely (unvectorized, of course).
Again this looks like missing vectorization of scalar code.
Note that the first complete unrolling pass unrolls loops that result in
smaller code. This interferes with vectorization in your case, so can
you try
Index: tree-ssa-loop-ivcanon.c
===================================================================
*** tree-ssa-loop-ivcanon.c (revision 139200)
--- tree-ssa-loop-ivcanon.c (working copy)
*************** tree_unroll_loops_completely (bool may_i
*** 359,374 ****
FOR_EACH_LOOP (li, loop, LI_ONLY_INNERMOST)
{
! if (may_increase_size && maybe_hot_bb_p (loop->header)
! /* Unroll outermost loops only if asked to do so or they do
! not cause code growth. */
! && (unroll_outer
! || loop_outer (loop_outer (loop))))
ul = UL_ALL;
else
ul = UL_NO_GROWTH;
! changed |= canonicalize_loop_induction_variables
! (loop, false, ul, !flag_tree_loop_ivcanon);
}
if (changed)
--- 359,378 ----
FOR_EACH_LOOP (li, loop, LI_ONLY_INNERMOST)
{
! /* Unroll outermost loops only if asked to do so. */
! if (!unroll_outer
! && !loop_outer (loop_outer (loop)))
! ul = UL_SINGLE_ITER;
! else if (may_increase_size && maybe_hot_bb_p (loop->header))
ul = UL_ALL;
else
ul = UL_NO_GROWTH;
! if (canonicalize_loop_induction_variables
! (loop, false, ul, !flag_tree_loop_ivcanon))
! {
! statistics_counter_event (cfun, "Loops completely unrolled", 1);
! changed = true;
! }
}
if (changed)
?
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |rguenth at gcc dot gnu dot
| |org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37150
