* [Bug tree-optimization/32378] can't determine dependence (distinct sections of an array)
2007-06-17 15:35 [Bug fortran/32378] New: " tprince at computer dot org
@ 2007-06-18 3:16 ` pinskia at gcc dot gnu dot org
2007-06-18 11:08 ` dorit at il dot ibm dot com
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2007-06-18 3:16 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from pinskia at gcc dot gnu dot org 2007-06-18 03:15 -------
I think some of this is related to PR 32075. (Looking into IR tells you that).
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|fortran |tree-optimization
GCC build triplet|x86_64-unknown-linux-gnu |
GCC host triplet|x86_64-unknown-linux-gnu |
GCC target triplet|x86_64-unknown-linux-gnu |
Keywords| |missed-optimization
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32378
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug tree-optimization/32378] can't determine dependence (distinct sections of an array)
2007-06-17 15:35 [Bug fortran/32378] New: " tprince at computer dot org
2007-06-18 3:16 ` [Bug tree-optimization/32378] " pinskia at gcc dot gnu dot org
@ 2007-06-18 11:08 ` dorit at il dot ibm dot com
2007-06-21 23:32 ` pinskia at gcc dot gnu dot org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: dorit at il dot ibm dot com @ 2007-06-18 11:08 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from dorit at il dot ibm dot com 2007-06-18 11:08 -------
I see this in the vectorizer dump file (with mainline from a few days ago):
(compute_affine_dependence
(stmt_a =
D.1423_50 = (*a_49(D))[D.1422_48])
(stmt_b =
(*a_49(D))[D.1420_51] = D.1425_54)
Data ref a:
(Data Ref:
stmt: D.1423_50 = (*a_49(D))[D.1422_48];
ref: (*a_49(D))[D.1422_48];
base_object: (*a_49(D))[0];
Access function 0: {pretmp.48_45 + 1, +, 1}_1
Access function 1: 0B
)
Data ref b:
(Data Ref:
stmt: (*a_49(D))[D.1420_51] = D.1425_54;
ref: (*a_49(D))[D.1420_51];
base_object: (*a_49(D))[0];
Access function 0: {0, +, 1}_1
Access function 1: 0B
)
affine dependence test not usable: access function not affine or constant.
(dependence classified: scev_not_known)
)
(compute_affine_dependence
(stmt_a =
D.1424_53 = (*b_52(D))[D.1420_51])
(stmt_b =
(*a_49(D))[D.1420_51] = D.1425_54)
)
(the IR looks a bit different than PR32075, but the data-rependence analysis
fails with the same problem). pinskia - are you still planning to address this
issue?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32378
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug tree-optimization/32378] can't determine dependence (distinct sections of an array)
2007-06-17 15:35 [Bug fortran/32378] New: " tprince at computer dot org
2007-06-18 3:16 ` [Bug tree-optimization/32378] " pinskia at gcc dot gnu dot org
2007-06-18 11:08 ` dorit at il dot ibm dot com
@ 2007-06-21 23:32 ` pinskia at gcc dot gnu dot org
2007-07-01 12:43 ` dorit at gcc dot gnu dot org
2007-08-19 13:47 ` dorit at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2007-06-21 23:32 UTC (permalink / raw)
To: gcc-bugs
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2007-06-21 23:32:19
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32378
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug tree-optimization/32378] can't determine dependence (distinct sections of an array)
2007-06-17 15:35 [Bug fortran/32378] New: " tprince at computer dot org
` (2 preceding siblings ...)
2007-06-21 23:32 ` pinskia at gcc dot gnu dot org
@ 2007-07-01 12:43 ` dorit at gcc dot gnu dot org
2007-08-19 13:47 ` dorit at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: dorit at gcc dot gnu dot org @ 2007-07-01 12:43 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from dorit at gcc dot gnu dot org 2007-07-01 12:43 -------
Dependence analysis now fails with a different message:
(compute_affine_dependence
(stmt_a =
D.1373_43 = (*a_42(D))[D.1372_41])
(stmt_b =
(*a_42(D))[D.1370_44] = D.1375_47)
(subscript_dependence_tester
(analyze_overlapping_iterations
(chrec_a = {pretmp.50_1 + 1, +, 1}_1)
(chrec_b = {0, +, 1}_1)
(analyze_siv_subscript
siv test failed: unimplemented.
)
(overlap_iterations_a = not known
)
(overlap_iterations_b = not known
)
)
(dependence classified: scev_not_known)
)
)
Sebastian - any thughts/plans?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32378
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug tree-optimization/32378] can't determine dependence (distinct sections of an array)
2007-06-17 15:35 [Bug fortran/32378] New: " tprince at computer dot org
` (3 preceding siblings ...)
2007-07-01 12:43 ` dorit at gcc dot gnu dot org
@ 2007-08-19 13:47 ` dorit at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: dorit at gcc dot gnu dot org @ 2007-08-19 13:47 UTC (permalink / raw)
To: gcc-bugs
------- Comment #6 from dorit at gcc dot gnu dot org 2007-08-19 13:47 -------
> Sebastian - any thughts/plans?
Here's another testcase:
subroutine sub(aa,bb,n,m)
implicit none
integer, intent(in) :: n,m
real, intent(inout) :: aa(n,m)
real, intent(in) :: bb(n,m)
integer :: i,j
do j= 2,n
do i = 1,m
aa(i,j)= aa(i,j-1)+bb(i,j-1)
enddo
enddo
end subroutine
end
Here too we get:
(compute_affine_dependence
(stmt_a =
D.1385_55 = (*aa_54(D))[D.1384_53])
(stmt_b =
(*aa_54(D))[D.1380_49] = D.1390_62)
(subscript_dependence_tester
(analyze_overlapping_iterations
(chrec_a = {pretmp.34_76 + 1, +, 1}_2)
(chrec_b = {pretmp.34_32 + 1, +, 1}_2)
(analyze_siv_subscript
siv test failed: unimplemented.
)
(overlap_iterations_a = not known
)
(overlap_iterations_b = not known
)
)
(dependence classified: scev_not_known)
)
)
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32378
^ permalink raw reply [flat|nested] 6+ messages in thread