On Thu, Nov 17, 2016 at 4:14 AM, Bill Schmidt
<wschm...@linux.vnet.ibm.com> wrote:
> On 11/16/16 9:08 AM, Richard Biener wrote:
>
>> On Tue, Nov 15, 2016 at 9:03 PM, Bill Schmidt
>> <wschm...@linux.vnet.ibm.com> wrote:
>>> - if ((any_pred_load_store || any_complicated_phi)
>>> - && !version_loop_for_if_conversion (loop))
>>> + /* Since we have no cost model, always version loops if vectorization
>>> + is enabled. Either version this loop, or if the pattern is right
>>> + for outer-loop vectorization, version the outer loop. In the
>>> + latter case we will still if-convert the original inner loop. */
>>> + /* FIXME: When SLP vectorization can handle if-conversion on its own,
>>> + predicate all of if-conversion on flag_tree_loop_vectorize. */
>>> + if ((any_pred_load_store || any_complicated_phi ||
>>> flag_tree_loop_vectorize)
>> I'd say given fun->has_force_vectorize_loops this should be
>>
>> if (flag_tree_loop_if_convert != 1
>>> + && !version_loop_for_if_conversion
>>> + (versionable_outer_loop_p (loop_outer (loop))
>>> + ? loop_outer (loop) : loop))
>>> goto cleanup;
>> and thus always version if the user didnt' specify -ftree-loop-if-convert
>> (-ftree-loop-if-convert-stores is dead, I forgot to remove uses).
>>
>> Can you as a first patch (after fixing the minor things above) commit
>> the patch w/o changing the condition under which we version
>> (but _do_ version the outer loop if possible?). This should be a strict
>> improvement enabling more outer loop vectorization.
>
> Done and committed. Thanks!
>
>>
>> The 2nd patch can then fix the PR and change the condition.
>>
>> Thus, ok with the nits fixed and the condition unchanged.
>>
>> Can you re-test the 2nd part with my suggested changed predicate?
>
> Yes, the new predicate works fine. New patch below, bootstrapped and tested
> on powerpc64le-unknown-linux-gnu, with only the bb-slp-cond-1.c regressions
> previously discussed. Is this ok for trunk?
Yes. Please open a bug for the bb-slp-cond-1.c testsuite FAIL (so we have an
excuse to either improve loop vectorization data dependence analysis or
BB vectorization in stage3).
Thanks,
Richard.
> Thanks,
> Bill
>
>>
>> Thanks,
>> Richard.
>>
> [gcc]
>
> 2016-11-16 Bill Schmidt <wschm...@linux.vnet.ibm.com>
> Richard Biener <rguent...@suse.de>
>
> PR tree-optimization/77848
> * tree-if-conv.c (tree_if_conversion): Always version loops unless
> the user specified -ftree-loop-if-convert.
>
> [gcc/testsuite]
>
> 2016-11-16 Bill Schmidt <wschm...@linux.vnet.ibm.com>
> Richard Biener <rguent...@suse.de>
>
> PR tree-optimization/77848
> * gfortran.dg/vect/pr77848.f: New test.
>
>
> Index: gcc/testsuite/gfortran.dg/vect/pr77848.f
> ===================================================================
> --- gcc/testsuite/gfortran.dg/vect/pr77848.f (revision 0)
> +++ gcc/testsuite/gfortran.dg/vect/pr77848.f (working copy)
> @@ -0,0 +1,24 @@
> +! PR 77848: Verify versioning is on when vectorization fails
> +! { dg-do compile }
> +! { dg-options "-O3 -ffast-math -fdump-tree-ifcvt -fdump-tree-vect-details" }
> +
> + subroutine sub(x,a,n,m)
> + implicit none
> + real*8 x(*),a(*),atemp
> + integer i,j,k,m,n
> + real*8 s,t,u,v
> + do j=1,m
> + atemp=0.d0
> + do i=1,n
> + if (abs(a(i)).gt.atemp) then
> + atemp=a(i)
> + k = i
> + end if
> + enddo
> + call dummy(atemp,k)
> + enddo
> + return
> + end
> +
> +! { dg-final { scan-tree-dump "LOOP_VECTORIZED" "ifcvt" } }
> +! { dg-final { scan-tree-dump "vectorized 0 loops in function" "vect" } }
> Index: gcc/tree-if-conv.c
> ===================================================================
> --- gcc/tree-if-conv.c (revision 242521)
> +++ gcc/tree-if-conv.c (working copy)
> @@ -2803,10 +2803,12 @@ tree_if_conversion (struct loop *loop)
> || loop->dont_vectorize))
> goto cleanup;
>
> - /* Either version this loop, or if the pattern is right for outer-loop
> - vectorization, version the outer loop. In the latter case we will
> - still if-convert the original inner loop. */
> - if ((any_pred_load_store || any_complicated_phi)
> + /* Since we have no cost model, always version loops unless the user
> + specified -ftree-loop-if-convert. Either version this loop, or if
> + the pattern is right for outer-loop vectorization, version the
> + outer loop. In the latter case we will still if-convert the
> + original inner loop. */
> + if (flag_tree_loop_if_convert != 1
> && !version_loop_for_if_conversion
> (versionable_outer_loop_p (loop_outer (loop))
> ? loop_outer (loop) : loop))
>
