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* [Bug middle-end/49969] New: not vectorized: data ref analysis failed
@ 2011-08-03 17:24 burnus at gcc dot gnu.org
2011-08-04 9:45 ` [Bug middle-end/49969] " rguenth at gcc dot gnu.org
2012-07-13 8:35 ` rguenth at gcc dot gnu.org
0 siblings, 2 replies; 3+ messages in thread
From: burnus at gcc dot gnu.org @ 2011-08-03 17:24 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49969
Summary: not vectorized: data ref analysis failed
Product: gcc
Version: 4.7.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: burnus@gcc.gnu.org
CC: irar@gcc.gnu.org, rguenther@suse.de
The following program does not vectorize. With Intel's ifort one gets the
message:
PERMUTED LOOP WAS VECTORIZED
while GCC just prints:
test.f90:6: note: not vectorized: data ref analysis failed D.1566_33 =
*iz_32(D)[D.1565_31];
test.f90:7: note: not vectorized: data ref analysis failed D.1566_33 =
*iz_32(D)[D.1565_31];
test.f90:2: note: vectorized 0 loops in function.
In case of GCC, it does not depend on the loop order - permuting does not
change anything. Also it is independent of the patch to PR 49957.
! From Polyhedron's ac.f90, line 746
SUBROUTINE SUSCEP(L,Iz,Dsus)
INTEGER L , Iz(L,L) , iznum
DOUBLE PRECISION Dsus
iznum = 0
DO iy = 1 , L
DO ix = 1 , L
iznum = iznum + Iz(iy,ix)
ENDDO
ENDDO
Dsus = DBLE(iznum)
Dsus = Dsus*Dsus
Dsus = Dsus/(L*L)
END
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug middle-end/49969] not vectorized: data ref analysis failed
2011-08-03 17:24 [Bug middle-end/49969] New: not vectorized: data ref analysis failed burnus at gcc dot gnu.org
@ 2011-08-04 9:45 ` rguenth at gcc dot gnu.org
2012-07-13 8:35 ` rguenth at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2011-08-04 9:45 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49969
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2011.08.04 09:44:45
CC| |spop at gcc dot gnu.org
Ever Confirmed|0 |1
--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-08-04 09:44:45 UTC ---
Well, that's because the evolution of D.1565_31 is
{{(stride.2_11 + offset.3_21) + 1, +, 1}_1, +, stride.2_11}_2
the loop needs interchange to be vectorized, but that doesn't work either
(no idea for the reason - the .graphite dump isn't very informative here,
well, maybe it runs into the exactly same issue and already gives up?)
Sebastian?
Confirmed anyway. Supposed to be vectorized with -floop-interchange.
^ permalink raw reply [flat|nested] 3+ messages in thread* [Bug middle-end/49969] not vectorized: data ref analysis failed
2011-08-03 17:24 [Bug middle-end/49969] New: not vectorized: data ref analysis failed burnus at gcc dot gnu.org
2011-08-04 9:45 ` [Bug middle-end/49969] " rguenth at gcc dot gnu.org
@ 2012-07-13 8:35 ` rguenth at gcc dot gnu.org
1 sibling, 0 replies; 3+ messages in thread
From: rguenth at gcc dot gnu.org @ 2012-07-13 8:35 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49969
Richard Guenther <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Blocks| |53947
--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-07-13 08:34:49 UTC ---
Link to vectorizer missed-optimization meta-bug.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2012-07-13 8:35 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2011-08-03 17:24 [Bug middle-end/49969] New: not vectorized: data ref analysis failed burnus at gcc dot gnu.org
2011-08-04 9:45 ` [Bug middle-end/49969] " rguenth at gcc dot gnu.org
2012-07-13 8:35 ` rguenth at gcc dot gnu.org
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