On 12/03/13 06:48, Jeff Law wrote:
On 12/02/13 08:47, Yufeng Zhang wrote:
Ping~
http://gcc.gnu.org/ml/gcc-patches/2013-11/msg03360.html
Thanks,
Yufeng
On 11/26/13 15:02, Yufeng Zhang wrote:
On 11/26/13 12:45, Richard Biener wrote:
On Thu, Nov 14, 2013 at 12:25 AM, Yufeng
Zhang<Yufeng.Zhang@arm.com> wrote:
On 11/13/13 20:54, Bill Schmidt wrote:
The second version of your original patch is ok with me with the
following changes. Sorry for the little side adventure into the
next-interp logic; in the end that's going to hurt more than it
helps in
this case. Thanks for having a look at it, anyway. Thanks also for
cleaning up this version to be less intrusive to common interfaces; I
appreciate it.
Thanks a lot for the review. I've attached an updated patch with the
suggested changes incorporated.
For the next-interp adventure, I was quite happy to do the
experiment; it's
a good chance of gaining insight into the pass. Many thanks for
your prompt
replies and patience in guiding!
Everything else looks OK to me. Please ask Richard for final
approval,
as I'm not a maintainer.
First a note, I need to check on voting for Bill as the slsr maintainer
from the steering committee. Voting was in progress just before the
close of stage1 development so I haven't tallied the results :-)
Looking forward to some good news! :)
Yes, you are right about the non-trivial 'base' tree are rarely shared.
The cached is introduced mainly because get_alternative_base () may
be
called twice on the same 'base' tree, once in the
find_basis_for_candidate () for look-up and the other time in
alloc_cand_and_find_basis () for record_potential_basis (). I'm happy
to leave out the cache if you think the benefit is trivial.
Without some sense of how expensive the lookups are vs how often the
cache hits it's awful hard to know if the cache is worth it.
I'd say take it out unless you have some sense it's really saving time.
It's a pretty minor implementation detail either way.
I think the affine tree routines are generally expensive; it is worth having
a cache to avoid calling them too many times. I run the slsr-*.c tests
under gcc.dg/tree-ssa/ and find out that the cache hit rates range from
55.6% to 90%, with 73.5% as the average. The samples may not well represent
the real world scenario, but they do show the fact that the 'base' tree can
be shared to some extent. So I'd like to have the cache in the patch.
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-slsr" } */
+
+typedef int arr_2[50][50];
+
+void foo (arr_2 a2, int v1)
+{
+ int i, j;
+
+ i = v1 + 5;
+ j = i;
+ a2 [i-10] [j] = 2;
+ a2 [i] [j++] = i;
+ a2 [i+20] [j++] = i;
+ a2 [i-3] [i-1] += 1;
+ return;
+}
+
+/* { dg-final { scan-tree-dump-times "MEM" 5 "slsr" } } */
+/* { dg-final { cleanup-tree-dump "slsr" } } */
scanning for 5 MEMs looks non-sensical. What transform do
you expect? I see other slsr testcases do similar non-sensical
checking which is bad, too.
As the slsr optimizes CAND_REF candidates by simply lowering them to
MEM_REF from e.g. ARRAY_REF, I think scanning for the number of MEM_REFs
is an effective check. Alternatively, I can add a follow-up patch to
add some dumping facility in replace_ref () to print out the replacing
actions when -fdump-tree-slsr-details is on.
I think adding some details to the dump and scanning for them would be
better. That's the only change that is required for this to move forward.
I've updated to patch to dump more details when -fdump-tree-slsr-details is
on. The tests have also been updated to scan for these new dumps instead of
MEMs.
I suggest doing it quickly. We're well past stage1 close at this point.
The bootstrapping on x86_64 is still running. OK to commit if it succeeds?