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* [Bug fortran/64207] New: vectorization report
@ 2014-12-06 6:26 mike at mikepage dot us
2014-12-06 10:44 ` [Bug fortran/64207] " Joost.VandeVondele at mat dot ethz.ch
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: mike at mikepage dot us @ 2014-12-06 6:26 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64207
Bug ID: 64207
Summary: vectorization report
Product: gcc
Version: 4.9.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
Assignee: unassigned at gcc dot gnu.org
Reporter: mike at mikepage dot us
gfortran --version
GNU Fortran (MacPorts gcc49 4.9.2_1) 4.9.2
gfortran -O3 -ftree-vectorize -ftree-vectorizer-verbose=6 foo.f90
is not issuing vectorization report
cat foo.f90
program main
real, dimension(1024, 1024) :: a,b,c
call random_number(a)
call random_number(b)
do i=1,1024
do j=1,1024
c(i,j) = a(j,i)*b(j,i)
end do
end do
print *,c
end program main
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug fortran/64207] vectorization report
2014-12-06 6:26 [Bug fortran/64207] New: vectorization report mike at mikepage dot us
@ 2014-12-06 10:44 ` Joost.VandeVondele at mat dot ethz.ch
2014-12-06 17:06 ` mike at mikepage dot us
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Joost.VandeVondele at mat dot ethz.ch @ 2014-12-06 10:44 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64207
Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
CC| |Joost.VandeVondele at mat dot ethz
| |.ch
Resolution|--- |FIXED
--- Comment #1 from Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> ---
-fopt-info is the replacement for -ftree-vectorizer-verbose, the latter is
deprecated
for example try -fopt-info-vec-missed or -fopt-info-all
best is to keep the part to analyze rather simple, since it generates a lot of
info that isn't always easy to understand:
> cat t.f90
subroutine s(a,b,c)
real, dimension(1024, 1024) :: a,b,c
do i=1,1024
do j=1,1024
c(i,j) = a(j,i)*b(j,i)
end do
end do
end subroutine
> gfortran -c -O3 -march=native -ffast-math -fopt-info-vec-missed t.f90
t.f90:3:0: note: not vectorized: complicated access pattern.
t.f90:3:0: note: bad data access.
t.f90:4:0: note: not consecutive access *c_19(D)[_10] = _18;
t.f90:4:0: note: not vectorized: complicated access pattern.
t.f90:4:0: note: bad data access.
[...]
> cat t.f90
subroutine s(a,b,c)
real, dimension(1024, 1024) :: a,b,c
do i=1,1024
do j=1,1024
c(j,i) = a(j,i)*b(j,i)
end do
end do
end subroutine
> gfortran -c -O3 -march=native -ffast-math -fopt-info-vec t.f90
t.f90:4:0: note: loop vectorized
t.f90:4:0: note: loop peeled for vectorization to enhance alignment
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug fortran/64207] vectorization report
2014-12-06 6:26 [Bug fortran/64207] New: vectorization report mike at mikepage dot us
2014-12-06 10:44 ` [Bug fortran/64207] " Joost.VandeVondele at mat dot ethz.ch
@ 2014-12-06 17:06 ` mike at mikepage dot us
2014-12-06 17:20 ` mike at mikepage dot us
2014-12-06 18:07 ` Joost.VandeVondele at mat dot ethz.ch
3 siblings, 0 replies; 5+ messages in thread
From: mike at mikepage dot us @ 2014-12-06 17:06 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64207
--- Comment #2 from Mike Page <mike at mikepage dot us> ---
Thanks, Joost.
I need to go find some current documentation.
Thanks for fixing the typo in my bad example.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug fortran/64207] vectorization report
2014-12-06 6:26 [Bug fortran/64207] New: vectorization report mike at mikepage dot us
2014-12-06 10:44 ` [Bug fortran/64207] " Joost.VandeVondele at mat dot ethz.ch
2014-12-06 17:06 ` mike at mikepage dot us
@ 2014-12-06 17:20 ` mike at mikepage dot us
2014-12-06 18:07 ` Joost.VandeVondele at mat dot ethz.ch
3 siblings, 0 replies; 5+ messages in thread
From: mike at mikepage dot us @ 2014-12-06 17:20 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64207
--- Comment #3 from Mike Page <mike at mikepage dot us> ---
BTW, I was using
https://gcc.gnu.org/projects/tree-ssa/vectorization.html#using
for my info on optimization options.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug fortran/64207] vectorization report
2014-12-06 6:26 [Bug fortran/64207] New: vectorization report mike at mikepage dot us
` (2 preceding siblings ...)
2014-12-06 17:20 ` mike at mikepage dot us
@ 2014-12-06 18:07 ` Joost.VandeVondele at mat dot ethz.ch
3 siblings, 0 replies; 5+ messages in thread
From: Joost.VandeVondele at mat dot ethz.ch @ 2014-12-06 18:07 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64207
--- Comment #4 from Joost VandeVondele <Joost.VandeVondele at mat dot ethz.ch> ---
(In reply to Mike Page from comment #3)
> BTW, I was using
> https://gcc.gnu.org/projects/tree-ssa/vectorization.html#using
> for my info on optimization options.
yes, I agree that there is lots of outdated info, also I had to search a while
to find the proper option name. Almost all hits online refer to the old option.
The web never forgets ;-)
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2014-12-06 18:07 UTC | newest]
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2014-12-06 6:26 [Bug fortran/64207] New: vectorization report mike at mikepage dot us
2014-12-06 10:44 ` [Bug fortran/64207] " Joost.VandeVondele at mat dot ethz.ch
2014-12-06 17:06 ` mike at mikepage dot us
2014-12-06 17:20 ` mike at mikepage dot us
2014-12-06 18:07 ` Joost.VandeVondele at mat dot ethz.ch
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