[Bug fortran/43829] Scalarization of reductions

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #31 from Mikael Morin <mikael at gcc dot gnu.org> 2011-02-07 18:49:10 UTC ---
Created attachment 23267
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23267
testcase

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

Mikael Morin <mikael at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #21016|0                           |1
        is obsolete|                            |

--- Comment #32 from Mikael Morin <mikael at gcc dot gnu.org> 2011-02-07 18:54:55 UTC ---
Created attachment 23268
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23268
More up-to-date patch

This deserves a safe place to stay.

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #33 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-03-01 15:41:36 UTC ---
(In reply to comment #32)
> Created attachment 23268 [details]
> More up-to-date patch

Although this patch is probably not suitable for stage 4, I have it in my tree
for some time without any problem. It would be interesting to know if it still
improves 465.tonto. My only remark is about the test in comment #31 for which
the dg-warning in 

  if (any(1+eid(sum(a,2))+ay+neid2 &
        (sum(a,2) &              ! { dg-warning "Creating array temporary" }
        )+1  /= 3*ay+2))        call abort

should be moved to the line above:

Warning: Creating array temporary at (1)
pr43829_7.f90:116.34:

  if (any(1+eid(sum(a,2))+ay+neid2 &
                                  1
Warning: Creating array temporary at (1)

and the block

  if (any(sum(                &
        a(sum(onesx(:,:),1),  &
          sum(onesy(:,:),1),  &
          sum(onesz(:,:),1)), &
        1) /= ax)) call abort

that generates

pr43829_7.f90:94.10:

        a(sum(onesx(:,:),1),  &
          1
Warning: Creating array temporary at (1)
pr43829_7.f90:94.28:

        a(sum(onesx(:,:),1),  &
                            1
Warning: Creating array temporary at (1)
pr43829_7.f90:95.28:

          sum(onesy(:,:),1),  &
                            1
Warning: Creating array temporary at (1)

Also "reshape((/ (i*i,i=1,size(a)) /), shape(a)), &" generates a warning:

pr43829_7.f90:82.8:

        reshape((/ (i*i,i=1,size(a)) /), shape(a)), &
        1
Warning: Creating array temporary at (1)

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #34 from Mikael Morin <mikael at gcc dot gnu.org> 2011-03-04 23:14:59 UTC ---
(In reply to comment #33)
> My only remark is about the test in comment #31 for which
> the dg-warning in 
> [...]
> should be moved to the line above:
> 
> and the block
> [...]
> that generates
> [...]

Thank you Dominique, I missed some of the temporaries as they were uncaught by
the testsuite. A problem with continued lines it seems. 

> 
> Also "reshape((/ (i*i,i=1,size(a)) /), shape(a)), &" generates a warning:
> 
> pr43829_7.f90:82.8:
> 
>         reshape((/ (i*i,i=1,size(a)) /), shape(a)), &
>         1
> Warning: Creating array temporary at (1)

I have to double check, but this one should be expanded at compile time.

[Bug fortran/43829] Scalarization of reductions

[matz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

Michael Matz <matz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #23268|0                           |1
        is obsolete|                            |

--- Comment #35 from Michael Matz <matz at gcc dot gnu.org> 2011-10-04 13:17:00 UTC ---
Created attachment 25409
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25409
Even more up-to-date patch

This patch applies to r179469.  The results on tonto, on a Bulldozer machine:

imf ./tonto.r179469.bdver.avx   3m22.045s
imf ./tonto.r179469.bdver.nosum 2m59.535s

That's with libimf preloaded.  And then it's actually faster then with ICC
(doesn't mean much, as on bulldozer we can use FMA4 and XOP).  Nevertheless
the speedup is now rougly 10%.  We really should work towards including
it for 4.7.

[Bug fortran/43829] Scalarization of reductions

[paul.richard.thomas at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #36 from paul.richard.thomas at gmail dot com <paul.richard.thomas at gmail dot com> 2011-10-04 16:04:48 UTC ---
Dear Michael,

I agree - we need the most up to date version to be (re-)submitted.  I
will review it.

Cheers

Paul

On Tue, Oct 4, 2011 at 3:17 PM, matz at gcc dot gnu.org
<gcc-bugzilla@gcc.gnu.org> wrote:
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829
>
> Michael Matz <matz at gcc dot gnu.org> changed:
>
>           What    |Removed                     |Added
> ----------------------------------------------------------------------------
>  Attachment #23268|0                           |1
>        is obsolete|                            |
>
> --- Comment #35 from Michael Matz <matz at gcc dot gnu.org> 2011-10-04 13:17:00 UTC ---
> Created attachment 25409
>  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25409
> Even more up-to-date patch
>
> This patch applies to r179469.  The results on tonto, on a Bulldozer machine:
>
> imf ./tonto.r179469.bdver.avx   3m22.045s
> imf ./tonto.r179469.bdver.nosum 2m59.535s
>
> That's with libimf preloaded.  And then it's actually faster then with ICC
> (doesn't mean much, as on bulldozer we can use FMA4 and XOP).  Nevertheless
> the speedup is now rougly 10%.  We really should work towards including
> it for 4.7.
>
> --
> Configure bugmail: http://gcc.gnu.org/bugzilla/userprefs.cgi?tab=email
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug.
>

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #37 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-04 21:56:15 UTC ---
(In reply to comment #35)
> Created attachment 25409 [details]
> Even more up-to-date patch
> 
Sorry, you should have asked for the latest patch.
I'll post a more up-to-date than the more up-to-date soon.

[Bug fortran/43829] Scalarization of reductions

[paul.richard.thomas at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #38 from paul.richard.thomas at gmail dot com <paul.richard.thomas at gmail dot com> 2011-10-05 06:40:45 UTC ---
Dear Mikael,

Very good - I'll give it urgent attention as soon as it appears.

Cheers

Paul

On Tue, Oct 4, 2011 at 11:56 PM, mikael at gcc dot gnu.org
<gcc-bugzilla@gcc.gnu.org> wrote:
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829
>
> --- Comment #37 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-04 21:56:15 UTC ---
> (In reply to comment #35)
>> Created attachment 25409 [details]
>> Even more up-to-date patch
>>
> Sorry, you should have asked for the latest patch.
> I'll post a more up-to-date than the more up-to-date soon.
>
> --
> Configure bugmail: http://gcc.gnu.org/bugzilla/userprefs.cgi?tab=email
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug.
>

[Bug fortran/43829] Scalarization of reductions

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #39 from Tobias Burnus <burnus at gcc dot gnu.org> 2011-10-05 14:10:30 UTC ---
Regarding the (In reply to comment #37)
> Sorry, you should have asked for the latest patch.
> I'll post a more up-to-date than the more up-to-date soon.

Thanks. One comment: I think you will increase the binary size by inlining the
reduction. Could you consider keeping the current libgfortran version and
protecting the scalarization by
  if (!optimize_size)

Or, if you replace unconditionally the library version, can you list the
library funcition at http://gcc.gnu.org/wiki/LibgfortranAbiCleanup to make sure
that it gets removed when gfortran breaks the ABI. (The latter has to happen
when we change the array descriptor.)

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #40 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-05 18:10:08 UTC ---
(In reply to comment #39)
> Regarding the (In reply to comment #37)
> > Sorry, you should have asked for the latest patch.
> > I'll post a more up-to-date than the more up-to-date soon.
> 
> Thanks. One comment: I think you will increase the binary size by inlining the
> reduction. Could you consider keeping the current libgfortran version and
> protecting the scalarization by
>   if (!optimize_size)

I'll give it some thought. 


> 
> Or, if you replace unconditionally the library version, can you list the
> library funcition at http://gcc.gnu.org/wiki/LibgfortranAbiCleanup to make sure
> that it gets removed when gfortran breaks the ABI. (The latter has to happen
> when we change the array descriptor.)

Well, with the patch in its current state, the library code can't be dropped
anyway as sum is inlined only if the DIM argument is constant.
I don't know if the latter condition can be lifted without making the code
awkward. The fact that the scalarizer manages dimensions as int (thus not as
tree) certainly doesn't help, and it's certainly not a 4.7 item.
Hopefully the constant case is sufficiently common to make the optimization
worth the bother.

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

Mikael Morin <mikael at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #25409|0                           |1
        is obsolete|                            |

--- Comment #41 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-08 16:26:31 UTC ---
Created attachment 25443
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25443
Most up-to-date patch

Here is the latest patch.
It has evolved quite a lot since the last submission, but the evolutions are
improved handling of array constructors, and slightly different scalarizer
structures, so that the code produced should not be worse than the previous
versions (but there should not be great improvements either).

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

Mikael Morin <mikael at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #23267|0                           |1
        is obsolete|                            |

--- Comment #42 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-08 16:29:57 UTC ---
Created attachment 25444
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25444
slightly updated testcase

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #43 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-08 17:57:43 UTC ---
(In reply to comment #39)
> Thanks. One comment: I think you will increase the binary size by inlining the
> reduction. Could you consider keeping the current libgfortran version and
> protecting the scalarization by
>   if (!optimize_size)
> 
This is included in the patch in comment #41. Unfortunately, it makes the test
(comment #42) fail with -Os in the testsuite. I don't know yet how I will
handle it. I would like to avoid forcing one optimization level if possible.
Any idea?

[Bug fortran/43829] Scalarization of reductions

[paul.richard.thomas at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #44 from paul.richard.thomas at gmail dot com <paul.richard.thomas at gmail dot com> 2011-10-09 09:48:00 UTC ---
Dear Mikael,

I have duly loaded up your patch - it looks very slick and
professional; it even works as intended!


>>
> This is included in the patch in comment #41. Unfortunately, it makes the test
> (comment #42) fail with -Os in the testsuite. I don't know yet how I will
> handle it. I would like to avoid forcing one optimization level if possible.
> Any idea?

I confirm you finding:

FAIL: gfortran.dg/function_optimize_7.f90  -O  scan-tree-dump-times
original "sum_r4" 1
FAIL: gfortran.dg/inline_sum_1.f90  -Os  (test for excess errors)
FAIL: gfortran.dg/select_type_12.f03  -O  (internal compiler error)
FAIL: gfortran.dg/select_type_12.f03  -O  (test for excess errors)
Running /svn/trunk/gcc/testsuite/gfortran.dg/gomp/gomp.exp ...
Running /svn/trunk/gcc/testsuite/gfortran.dg/graphite/graphite.exp ...
Running /svn/trunk/gcc/testsuite/gfortran.dg/guality/guality.exp ...
Running /svn/trunk/gcc/testsuite/gfortran.dg/lto/lto.exp ...
Running /svn/trunk/gcc/testsuite/gfortran.dg/vect/vect.exp ...
Running /svn/trunk/gcc/testsuite/gfortran.fortran-torture/compile/compile.exp
...
Running /svn/trunk/gcc/testsuite/gfortran.fortran-torture/execute/execute.exp
...
FAIL: gfortran.fortran-torture/execute/entry_4.f90 execution,  -O2
FAIL: gfortran.fortran-torture/execute/entry_4.f90 execution,  -O2
-fomit-frame-pointer -finline-functions
FAIL: gfortran.fortran-torture/execute/entry_4.f90 execution,  -O2
-fomit-frame-pointer -finline-functions -funroll-loops
FAIL: gfortran.fortran-torture/execute/entry_4.f90 execution,  -O2
-fbounds-check
FAIL: gfortran.fortran-torture/execute/entry_4.f90 execution,  -O3 -g
FAIL: gfortran.fortran-torture/execute/entry_4.f90 execution, -O2
-ftree-vectorize -msse2

The function_optimize_7.f90 failure is obviously trivial.  Both the
select_type_12.f03 and the entry_4.f90 failures have crept in during
the last few days and appear to be some middle-end fault.

As for your inline_sum_1.f90:  The failure here is dues to extra
temporary array warnings with -Os.  I tried switching on and off the
extra optimizations in Os versus O2 but could not identify the
culprit.  That said, the test runs correctly with -Os.

What I would do is to double up the test; one with { dg-do compile }
and -Warray-temporaries and trhe other with { dg-do run } only.

Cheers

Paul

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #45 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2011-10-09 16:01:27 UTC ---
> Thanks. One comment: I think you will increase the binary size by inlining the
> reduction. Could you consider keeping the current libgfortran version and
> protecting the scalarization by
>  if (!optimize_size)

When compiling the test in comment #43 with -O2, the size of the a.out file is

[macbook] f90/bug% ll a.out
-rwxr-xr-x 1 dominiq staff 17752 Oct  9 17:55 a.out*

with -Os it is

[macbook] f90/bug% ll a.out
-rwxr-xr-x 1 dominiq staff 30216 Oct  9 17:54 a.out*

Are these numbers misleading, or once again compiling for size does not give
the smallest size?

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #46 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-09 16:44:19 UTC ---
(In reply to comment #45)
> Are these numbers misleading, or once again compiling for size does not give
> the smallest size?

Well, to begin with, I don't think the test is close to a real world case.
It initializes a couple of arrays, and then applies to them various
computations involving sum which it basically throws away afterwards. I
wouldn't be surprised if some of the computations could be optimized away or
shared between the different checks. I'm purely speculating here, but that
would explain the size difference between inlined and then removed code vs kept
around library call.

Checks like this (for example) are good candidates for removal:
  if (any(sum(sum(a,1),1) /= sum(sum(a,2),1))) call abort

[Bug fortran/43829] Scalarization of reductions

[rguenther at suse dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #47 from rguenther at suse dot de <rguenther at suse dot de> 2011-10-10 09:05:29 UTC ---
On Sat, 8 Oct 2011, mikael at gcc dot gnu.org wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829
> 
> --- Comment #43 from Mikael Morin <mikael at gcc dot gnu.org> 2011-10-08 17:57:43 UTC ---
> (In reply to comment #39)
> > Thanks. One comment: I think you will increase the binary size by inlining the
> > reduction. Could you consider keeping the current libgfortran version and
> > protecting the scalarization by
> >   if (!optimize_size)
> > 
> This is included in the patch in comment #41. Unfortunately, it makes the test
> (comment #42) fail with -Os in the testsuite. I don't know yet how I will
> handle it. I would like to avoid forcing one optimization level if possible.
> Any idea?

/* { dg-skip-if "" { *-*-* } { "-Os" } { "" } } */

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #48 from Mikael Morin <mikael at gcc dot gnu.org> 2011-11-04 00:31:23 UTC ---
Author: mikael
Date: Fri Nov  4 00:31:19 2011
New Revision: 180920

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=180920
Log:
    PR fortran/43829
    * trans-array.c (gfc_conv_expr_descriptor): Accept the inline intrinsic
    case in the assertion.
    * trans-intrinsic (enter_nested_loop): New function.
    (gfc_conv_intrinsic_arith): Support non-scalar cases.
    (nest_loop_dimension, walk_inline_intrinsic_arith): New functions.
    (walk_inline_intrinsic_function): Handle sum and product.
    (gfc_inline_intrinsic_function_p): Ditto.
    * trans.h (gfc_get_loopinfo): New macro.


Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-array.c
    trunk/gcc/fortran/trans-intrinsic.c
    trunk/gcc/fortran/trans.h

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #49 from Mikael Morin <mikael at gcc dot gnu.org> 2011-11-04 00:45:52 UTC ---
Author: mikael
Date: Fri Nov  4 00:45:48 2011
New Revision: 180922

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=180922
Log:
    PR fortran/43829
    * gfortran.dg/function_optimize_7.f90: Disable sum inlining.
    * gfortran.dg/inline_sum_1.f90: New.
    * gfortran.dg/inline_sum_2.f90: New.
    * gfortran.dg/inline_sum_bounds_check_1.f90: New.
    * gfortran.dg/inline_sum_bounds_check_2.f90: New.
    * gfortran.dg/inline_product_1.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/inline_product_1.f90
    trunk/gcc/testsuite/gfortran.dg/inline_sum_1.f90
    trunk/gcc/testsuite/gfortran.dg/inline_sum_2.f90
    trunk/gcc/testsuite/gfortran.dg/inline_sum_bounds_check_1.f90
    trunk/gcc/testsuite/gfortran.dg/inline_sum_bounds_check_2.f90
Modified:
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/function_optimize_7.f90

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #50 from Mikael Morin <mikael at gcc dot gnu.org> 2011-11-04 01:07:42 UTC ---
I didn't want to flood this PR with commit logs, so here are all the
patches/revisions relevant to this PR:

patch  revision
===============
01     180842
02     180843
03     180844
04     180846
05     180847
06     180848
08     180849
07     180850
09     180851
10     180852
11     180853
12     180855
13     180856
14     180857
15     180858
16     180859
17     180860
18     180861
19     180862
20     180864
21     180865
22     180866
23     180867
24     180868
25     180869
26     180870
27     180872
28     180873
29     180875
30     180877
31     180880
32     180881
33     180882
34     180883
35     180884
36     180885
37     180886
38     180887
39     180888
40     180889
41     180890
42     180891
43     480892
44     180893
45     180894
46     180895
47     180897
48     180898
49     180899
50     180900
51     180901
52     180902
53     180903
54     180904
55     180905
56     180906
57     180907
58     180908
59     180909
60     180910
61     180911
62     180913
63     180917
64     180918
65     180919
66     180920
tests  180922

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

Mikael Morin <mikael at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

--- Comment #51 from Mikael Morin <mikael at gcc dot gnu.org> 2011-11-04 01:09:00 UTC ---
The feature should now be implemented.

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

--- Comment #52 from Mikael Morin <mikael at gcc dot gnu.org> 2011-11-25 20:18:35 UTC ---
Author: mikael
Date: Fri Nov 25 20:18:21 2011
New Revision: 181730

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=181730
Log:
fortran/
    PR fortran/51250
    PR fortran/43829
    * trans-array.c (gfc_trans_create_temp_array): Get dimension from
    the right gfc_ss struct.

testsuite/
    PR fortran/51250
    PR fortran/43829
    * gfortran.dg/inline_sum_3.f90: New test.


Added:
    trunk/gcc/testsuite/gfortran.dg/inline_sum_3.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-array.c
    trunk/gcc/testsuite/ChangeLog

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

Mikael Morin <mikael at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |rajiv.adhikary at amd dot
                   |                            |com

--- Comment #53 from Mikael Morin <mikael at gcc dot gnu.org> 2012-03-04 19:13:53 UTC ---
*** Bug 36841 has been marked as a duplicate of this bug. ***

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #30 from mikael at gcc dot gnu dot org  2010-09-13 17:09 -------
(In reply to comment #29)
> I also think this pr is related to pr43829.
> 

It couldn't be more ;-)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens dot fr]

------- Comment #29 from dominiq at lps dot ens dot fr  2010-09-13 09:09 -------
> But it can still be updated and committed before the end of stage 1. :-)

I hope so!-) I also think this pr is related to pr43829.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #28 from mikael at gcc dot gnu dot org  2010-09-08 17:21 -------
(In reply to comment #27)
> What is the fate of the patch in comment #19?
> 
Some (admittedly small) parts of the patch are already on trunk.
The transpose patches still waiting review at
http://gcc.gnu.org/ml/fortran/2010-09/msg00109.html are the first important
step to commit this patch (they prevent one regression).
The rest is decaying. :-(
But it can still be updated and committed before the end of stage 1. :-)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens dot fr]

------- Comment #27 from dominiq at lps dot ens dot fr  2010-09-08 11:29 -------
What is the fate of the patch in comment #19?


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #26 from rguenth at gcc dot gnu dot org  2010-06-28 09:35 -------
(In reply to comment #21)
> With the patch in comment #19, the test suite pass with -m32 and -m64, but for
> gfortran.dg/transpose_2.f90 which needs an adjustment of the dg-error.
> 
> AFAICT the SUM of the different tests are scalarized (it would be interesting
> to have some timings before and after the patch for 465.tonto).

                                  Estimated                       Estimated
                Base     Base       Base        Peak     Peak       Peak
Benchmarks      Ref.   Run Time     Ratio       Ref.   Run Time     Ratio
-------------- ------  ---------  ---------    ------  ---------  ---------
465.tonto        9840        390       25.2 S    9840        361       27.3 S
465.tonto        9840        391       25.2 S    9840        361       27.3 *
465.tonto        9840        390       25.2 *    9840        362       27.2 S
==============================================================================
465.tonto        9840        390       25.2 *    9840        361       27.3 *

base is trunk r161367, peak is trunk r161367 + the patch from comment #19.
Flags are -O3 -ffast-math -funroll-loops -march=core2, executed on an
iCore7 @ 3.3GHz.

Thus your patch improves performance by 7.5% which is very nice and even
above what I expected (compared to manual source manipulation of the
hottest SUM).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[paul dot richard dot thomas at gmail dot com]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1176 bytes --]



------- Comment #25 from paul dot richard dot thomas at gmail dot com  2010-06-28 04:27 -------
Subject: Re:  Scalarization of reductions

Dear Mikael,

> -         gfc_find_sym_tree (name, gfc_current_ns, 0, &st);
> -         st->n.sym = *result;
>          st = gfc_get_unique_symtree (gfc_current_ns);
> -         st->n.sym = sym;
> +         gfc_assign_symbol (&st->n.sym, sym);
> +         gfc_find_sym_tree (name, gfc_current_ns, 0, &st);
> +         gfc_assign_symbol (&st->n.sym, *result);
>        }
>     }
>   else
>
> i.e. the two symbol assignments are exchanged so that the symbol is not deleted
> between them.

...snip...

> -  return vtab;
> +  found_sym = vtab;
> +
> +cleanup:
> +  /* It is unexpected to have some symbols added at resolution or code
> +     generation time. We commit the changes in order to keep a clean state.
> */
> +  if (found_sym)
> +    gfc_commit_symbols ();
> +  else
> +    gfc_undo_symbols ();
> +
> +  return found_sym;
>  }

I have been round long enough that I should have remembered all of this :-(

Thanks!

Paul


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens dot fr]

------- Comment #24 from dominiq at lps dot ens dot fr  2010-06-27 21:30 -------
(In reply to comment #23)
> Now I have forgotten another ICE with the patch: the second invalid test in
> comment #2 gives

See pr44693.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens dot fr]

------- Comment #23 from dominiq at lps dot ens dot fr  2010-06-27 20:05 -------
(In reply to comment #22)
> > (although I am puzzled by the following error for the second test:
> >          IF(DBUG.AND.NX.GT.0) THEN
> >                      1
> > Error: Operands of logical operator '.and.' at (1) are REAL(4)/LOGICAL(4)
> > where NX is an INTEGER(4) rather than a LOGICAL(4)).
> 
> The error seems to be OK: Seemingly "DBUG" is REAL(4) and the expression (NX <
> 0) is a default-kind logical.

OK, I did not parse NX.GT.0.

Now I have forgotten another ICE with the patch: the second invalid test in
comment #2 gives

pr43829_2.f90: In function 'test1':
pr43829_2.f90:4:0: internal compiler error: in gfc_conv_section_startstride, at
fortran/trans-array.c:3114


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[burnus at gcc dot gnu dot org]

------- Comment #22 from burnus at gcc dot gnu dot org  2010-06-27 19:44 -------
(In reply to comment #21)
> (although I am puzzled by the following error for the second test:
>          IF(DBUG.AND.NX.GT.0) THEN
>                      1
> Error: Operands of logical operator '.and.' at (1) are REAL(4)/LOGICAL(4)
> where NX is an INTEGER(4) rather than a LOGICAL(4)).

The error seems to be OK: Seemingly "DBUG" is REAL(4) and the expression (NX <
0) is a default-kind logical.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens dot fr]

------- Comment #21 from dominiq at lps dot ens dot fr  2010-06-27 19:20 -------
With the patch in comment #19, the test suite pass with -m32 and -m64, but for
gfortran.dg/transpose_2.f90 which needs an adjustment of the dg-error.

AFAICT the SUM of the different tests are scalarized (it would be interesting
to have some timings before and after the patch for 465.tonto).

The ICEs for the tests in pr44660 are now replaced with errors:

Error: Unexpected EQUIVALENCE statement at (1)

(although I am puzzled by the following error for the second test:


pr44660_1.f90:2.21:

         IF(DBUG.AND.NX.GT.0) THEN
                     1
Error: Operands of logical operator '.and.' at (1) are REAL(4)/LOGICAL(4)

where NX is an INTEGER(4) rather than a LOGICAL(4)).

The test in pr39304 ICE with

pr39304.f90: In function 'sum_k1a':
pr39304.f90:2626:0: internal compiler error: in conv_intrinsic_arith, at
fortran/trans-intrinsic.c:1875

instead of

pr39304.f90: In function 'sd_matrix_one':
pr39304.f90:440:0: internal compiler error: Segmentation fault

I see several ICEs:

f951: internal compiler error: in match_procedure_in_type, at
fortran/decl.c:7809

in the tests from pr41951, pr43199, and pr43896. Note that the later compiled
with trunk does not link with:

Undefined symbols:
  "_vtab$t_rotation_matrix.2314", referenced from:
      ___m_vector_MOD_rotation_matrix_times_vector in cc80aib8.o
...

and pr41951.f90 ICE with

f951: internal compiler error: in gfc_match_varspec, at fortran/primary.c:1821

I am probably missing other differences, but this represents most of them.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #20 from mikael at gcc dot gnu dot org  2010-06-27 12:50 -------
(In reply to comment #17)
> With the patch in comment #13 I get the following failures:
> 
> 
> FAIL: gfortran.dg/entry_10.f90  -O0  (internal compiler error)
> ...
> FAIL: gfortran.dg/entry_13.f90  -O0  (internal compiler error)
> ...
> FAIL: gfortran.dg/entry_16.f90  -O0  (internal compiler error)
Fixed. 

For info the relevant hunk is :
diff --git a/decl.c b/decl.c
index aa7a266..d062433 100644
--- a/decl.c
+++ b/decl.c
@@ -840,10 +850,10 @@ get_proc_name (const char *name, gfc_symbol **result,
bool module_fcn_entry)
             can be applied.  */
          (*result)->ns = gfc_current_ns;

-         gfc_find_sym_tree (name, gfc_current_ns, 0, &st);
-         st->n.sym = *result;
          st = gfc_get_unique_symtree (gfc_current_ns);
-         st->n.sym = sym;
+         gfc_assign_symbol (&st->n.sym, sym);
+         gfc_find_sym_tree (name, gfc_current_ns, 0, &st);
+         gfc_assign_symbol (&st->n.sym, *result);
        }
     }
   else

i.e. the two symbol assignments are exchanged so that the symbol is not deleted
between them. 



> 
> I have also a dozen ICEs in my favorite can of worms, for instance with
> 
> 
> module grid_module
>   implicit none 
>   type grid
>   end type
>   type field
>     type(grid) :: mesh
>   end type
> contains
>   real function return_x(this)
>     class(grid) :: this
>   end function
> end module 
> 
> module field_module
>   use grid_module, only: field,return_x
>   implicit none 
> contains
>   subroutine output(this)
>     class(field) :: this
>     print *,return_x(this%mesh)
>   end subroutine
> end module
> 
> 
There was a missing "end" statement to make it fail.

Fixed, for info the relevant part is the change in gfc_find_symbol_vtab,
espcially this hunk: 

diff --git a/class.c b/class.c
index 37b9cf0..11af809 100644
--- a/class.c
+++ b/class.c
@@ -641,7 +730,17 @@ gfc_find_derived_vtab (gfc_symbol *derived, bool resolved)
     add_generics_to_declared_vtab (derived, vtab->ts.u.derived,
                                   derived, resolved);

-  return vtab;
+  found_sym = vtab;
+
+cleanup:
+  /* It is unexpected to have some symbols added at resolution or code
+     generation time. We commit the changes in order to keep a clean state. 
*/
+  if (found_sym)
+    gfc_commit_symbols ();
+  else
+    gfc_undo_symbols ();
+
+  return found_sym;
 }




-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #19 from mikael at gcc dot gnu dot org  2010-06-27 12:42 -------
Created an attachment (id=21016)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=21016&action=view)
Updated patch


-- 

mikael at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #21002|0                           |1
        is obsolete|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #18 from mikael at gcc dot gnu dot org  2010-06-26 09:06 -------
(In reply to comment #17)
> The reason for the failures with entry_* is
> 
> [macbook] f90/bug% gfc /opt/gcc/_clean/gcc/testsuite/gfortran.dg/entry_10.f90
> f951(52154) malloc: *** error for object 0x1419161b0: pointer being freed was
> not allocated
> *** set a breakpoint in malloc_error_break to debug
> f951: internal compiler error: Abort trap
I will look into these. 

> 
> For the transpose test the runtime error is
> 
> At line 16 of file /opt/gcc/_clean/gcc/testsuite/gfortran.dg/transpose_2.f90
> Fortran runtime error: Array bound mismatch for dimension 1 of array 'b' (3/2)
> 
> instead of 
> 
> Fortran runtime error: Incorrect extent in return value of TRANSPOSE intrinsic
> in dimension 1: is 2, should be 3
I get these too, but the difference is just because the shape mismatch is now
caught by the scalarizer instead of the libgfortran.

> 
> I have also a dozen ICEs in my favorite can of worms, for instance with
> 
> 
> module grid_module
>   implicit none 
>   type grid
>   end type
>   type field
>     type(grid) :: mesh
>   end type
> contains
>   real function return_x(this)
>     class(grid) :: this
>   end function
> end module 
> 
> module field_module
>   use grid_module, only: field,return_x
>   implicit none 
> contains
>   subroutine output(this)
>     class(field) :: this
>     print *,return_x(this%mesh)
>   end subroutine
> end module
> 
> 
> [macbook] f90/bug% gfc pr42051_3.f90
> pr42051_3.f90:21:0: internal compiler error: Segmentation fault
> Please submit a full bug report,
> 
I will have a look too.


Thanks for testing.
There are probably some other regressions still uncaught. 
I will have to do a full valgrind-testing-enabled testsuite run at some point.
:-(


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[dominiq at lps dot ens dot fr]

------- Comment #17 from dominiq at lps dot ens dot fr  2010-06-25 22:08 -------
With the patch in comment #13 I get the following failures:


FAIL: gfortran.dg/entry_10.f90  -O0  (internal compiler error)
...
FAIL: gfortran.dg/entry_13.f90  -O0  (internal compiler error)
...
FAIL: gfortran.dg/entry_16.f90  -O0  (internal compiler error)
...

FAIL: gfortran.dg/transpose_2.f90  -O0  output pattern test, is At line 16 of
file /opt/gcc/work/gcc/testsuite/gfortran.dg/transpose_2.f90

The reason for the failures with entry_* is

[macbook] f90/bug% gfc /opt/gcc/_clean/gcc/testsuite/gfortran.dg/entry_10.f90
f951(52154) malloc: *** error for object 0x1419161b0: pointer being freed was
not allocated
*** set a breakpoint in malloc_error_break to debug
f951: internal compiler error: Abort trap

For the transpose test the runtime error is

At line 16 of file /opt/gcc/_clean/gcc/testsuite/gfortran.dg/transpose_2.f90
Fortran runtime error: Array bound mismatch for dimension 1 of array 'b' (3/2)

instead of 

Fortran runtime error: Incorrect extent in return value of TRANSPOSE intrinsic
in dimension 1: is 2, should be 3

I have also a dozen ICEs in my favorite can of worms, for instance with


module grid_module
  implicit none 
  type grid
  end type
  type field
    type(grid) :: mesh
  end type
contains
  real function return_x(this)
    class(grid) :: this
  end function
end module 

module field_module
  use grid_module, only: field,return_x
  implicit none 
contains
  subroutine output(this)
    class(field) :: this
    print *,return_x(this%mesh)
  end subroutine
end module


[macbook] f90/bug% gfc pr42051_3.f90
pr42051_3.f90:21:0: internal compiler error: Segmentation fault
Please submit a full bug report,


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenther at suse dot de]

------- Comment #16 from rguenther at suse dot de  2010-06-25 09:45 -------
Subject: Re:  Scalarization of reductions

On Fri, 25 Jun 2010, mikael at gcc dot gnu dot org wrote:

> ------- Comment #15 from mikael at gcc dot gnu dot org  2010-06-25 09:42 -------
> Isn't there a problem with the size of the patch ?
> pr43829_3.diff  46.78 KB
> 
> I get here:
> % du -h pr43829_3.diff  
> 240K    pr43829_3.diff
> %
> 
> At least it is not truncated (I have just checked).

Downloading it shows

/tmp> du -h attachment.cgi?id=21002
220K    attachment.cgi?id=21002

so I guess bugzilla reports compressed size (it stores compresses 
plaintext)

Richard.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #15 from mikael at gcc dot gnu dot org  2010-06-25 09:42 -------
Isn't there a problem with the size of the patch ?
pr43829_3.diff  46.78 KB

I get here:
% du -h pr43829_3.diff  
240K    pr43829_3.diff
%

At least it is not truncated (I have just checked).


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #14 from mikael at gcc dot gnu dot org  2010-06-25 09:36 -------
TODO:
 * testcases to check anything that might be impacted by the patch
 * split the patch for review & commit


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #13 from mikael at gcc dot gnu dot org  2010-06-25 09:34 -------
Created an attachment (id=21002)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=21002&action=view)
Updated patch

As I was having memory corruption regressions, I started to run valgrind on
some testcases, whose fixes brought new memory problems, and so on.
Now the patch contains a non negligible part of completely unrelated memory
fixes, and also random other things (dead code removal, if-blocks turned into
asserts, ...).


-- 

mikael at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #20726|0                           |1
        is obsolete|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #12 from mikael at gcc dot gnu dot org  2010-06-25 09:27 -------
(In reply to comment #11)
> However, regressions are now on transpose :
>  - alloc_comp_transformational_1.f90 : double free on function exit. I will
> have to investigate.
Fixed

>  - char_length_8.f90 : reshape doesn't like being passed a transposed array as
> target argument because the shape doesn't match then. I will look if i can fix
> reshape without recursing into some other regression.
Fixed.

>  - transpose_2.f90 : I will have to see if it is a real regression or if only
> the error message has changed. 
The error message has changed, no real regression. 

> 
> There is also this strange one.
>  - pr43984.f90 : memory allocation error at compile time (???!!)
It was a double free, fixed.  


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #11 from mikael at gcc dot gnu dot org  2010-05-22 19:36 -------
Created an attachment (id=20726)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20726&action=view)
updated patch

Update on this :
The attached patch seems to work on sum. 
I plan to reorganize some structs, but the behavior will remain the same. 

Regression fixes apart, what's different in this patch, is that the scalarizer
is aware of nested loops (in the previous patch, loops were removed/added at
appropriate places to fit the scalarizer's expectations). 

The patch also handles inlining for transpose because inlining was an easy fix
to a regression there was. 


However, regressions are now on transpose :
 - alloc_comp_transformational_1.f90 : double free on function exit. I will
have to investigate.
 - char_length_8.f90 : reshape doesn't like being passed a transposed array as
target argument because the shape doesn't match then. I will look if i can fix
reshape without recursing into some other regression.
 - transpose_2.f90 : I will have to see if it is a real regression or if only
the error message has changed. 

There is also this strange one.
 - pr43984.f90 : memory allocation error at compile time (???!!)


-- 

mikael at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #20558|0                           |1
        is obsolete|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #10 from rguenth at gcc dot gnu dot org  2010-05-05 15:44 -------
Indeed the patch looks a lot nicer and less like a hack than mine.

Re-assigning to you ;)


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|rguenth at gcc dot gnu dot  |mikael at gcc dot gnu dot
                   |org                         |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[pault at gcc dot gnu dot org]

------- Comment #9 from pault at gcc dot gnu dot org  2010-05-05 05:07 -------
(In reply to comment #8)
> Created an attachment (id=20558)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20558&action=view) [edit]
> draft patch

Mikael,

I am pretty much out of the loop for the next two weeks because I am on trips
for my day-time work.  In order to rush this along, you might have to walk one
of the others through your patch or to describe its core function here.

As far as I can see from a quick look, most of the patch is consequent on the
change to gfc_ss_info and that most of the meat comes at the end.  I have not
yet studied that in detail but it looks as if it is pretty easily explained.

Anyway, welcome back!

Paul


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[mikael at gcc dot gnu dot org]

------- Comment #8 from mikael at gcc dot gnu dot org  2010-05-04 23:08 -------
Created an attachment (id=20558)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20558&action=view)
draft patch

This uses the scalarizer to inline. 
The gfc_loopinfo is modified twice, first after walking args for passing
through the scalarizer with the same shape as other arrays, and then before the
expression evaluation (it is restored). 

There is still a problem with vector subscript but other tests should work
fine. 
And there are probably regressions.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #7 from rguenth at gcc dot gnu dot org  2010-04-23 16:09 -------
Mine.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2010-04-21 12:51:53         |2010-04-23 16:09:17
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #6 from rguenth at gcc dot gnu dot org  2010-04-22 15:39 -------
Reduced testcase:

template <class T> void void_cast_register(T *) __attribute__ ((used));
template <class T> void void_cast_register(T *) { }


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #5 from rguenth at gcc dot gnu dot org  2010-04-22 14:00 -------
Now onto

  subroutine test1(esss,Ix,Iyz)
    real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
    real(kind=kind(1.0d0)), dimension(:,:) :: Ix,Iyz
    esss = sum(Ix * Iyz, 1)
  end subroutine

noting that we can exchange the sum and the indexing of the assignment
making the sum() of rank one (and thus eligible for inline expansion).

Thus, expand it as

  do i=1,size(esss)
    esss(i) = sum(Ix(i,:) * Iyz(i,:))
  end do


An even simpler testcase where we want to do this exchange is

  subroutine test0(esss,Ix,Iyz)
    real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
    real(kind=kind(1.0d0)), dimension(:,:), intent(in) :: Ix
    esss = sum(Ix, 1)
  end subroutine

Thus, whenever the reduction is one-dimensional (though in this simpler
testcase we do not avoid the temporary for the sum intrinsic argument
which was the point of the excercise).  So, slightly more complicated
to show that this is still beneficial:

  subroutine test0(esss,Ix,Iyz)
    real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
    real(kind=kind(1.0d0)), dimension(:,:), intent(in) :: Ix
    esss = esss + sum(Ix, 1)
  end subroutine


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2010-04-22 08:34 -------
Subject: Bug 43829

Author: rguenth
Date: Thu Apr 22 08:34:41 2010
New Revision: 158632

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=158632
Log:
2010-04-22  Richard Guenther  <rguenther@suse.de>

        PR fortran/43829
        * resolve.c (gfc_resolve_index): Wrap around ...
        (gfc_resolve_index_1): ... this.  Add parameter to allow
        any integer kind index type.
        (resolve_array_ref): Allow any integer kind for the start
        index of an array ref.

        * gfortran.dg/vector_subscript_6.f90: New testcase.
        * gfortran.dg/assign_10.f90: Adjust.

Added:
    trunk/gcc/testsuite/gfortran.dg/vector_subscript_6.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/resolve.c
    trunk/gcc/fortran/trans-array.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gfortran.dg/assign_10.f90


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #3 from rguenth at gcc dot gnu dot org  2010-04-21 14:26 -------
subroutine test0(esss,Ix, e_x)
  real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
  real(kind=kind(1.0d0)), dimension(:) :: Ix
  integer(kind=kind(1)), dimension(:) :: e_x
  esss = Ix(e_x)
end subroutine

where we create the temporary during gfc_conv_loop_setup ->
gfc_add_loop_ss_code
when handling the GFC_SS_SECTION subscript e_x and want to get its array
descriptor.

To be able to specialize this we'd need to know whether at the end we're
going to need a descriptor for the GFC_SS_SECTION (because we are passing
it to a function or so) or whether we are going to access single elements only.

It looks like this is all because of the convert intrinsic called by
__convert_i4_i8[[((test0:e_x(FULL)))]] which is emitted regardless
of the type of e_x (even if it is integer(kind=kind(8))).

Testcase is fixed by

Index: gcc/fortran/resolve.c
===================================================================
--- gcc/fortran/resolve.c       (revision 158590)
+++ gcc/fortran/resolve.c       (working copy)
@@ -4007,8 +4007,7 @@ gfc_resolve_index (gfc_expr *index, int
                        &index->where) == FAILURE)
       return FAILURE;

-  if (index->ts.kind != gfc_index_integer_kind
-      || index->ts.type != BT_INTEGER)
+  if (index->ts.type != BT_INTEGER)
     {
       gfc_clear_ts (&ts);
       ts.type = BT_INTEGER;
Index: gcc/fortran/trans-array.c
===================================================================
--- gcc/fortran/trans-array.c   (revision 158590)
+++ gcc/fortran/trans-array.c   (working copy)
@@ -2434,6 +2434,7 @@ gfc_conv_array_index_offset (gfc_se * se
                                          gfc_conv_array_data (desc));
          index = gfc_build_array_ref (data, index, NULL);
          index = gfc_evaluate_now (index, &se->pre);
+         index = fold_convert (gfc_array_index_type, index);

          /* Do any bounds checking on the final info->descriptor index.  */
          index = gfc_trans_array_bound_check (se, info->descriptor,


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829

[Bug fortran/43829] Scalarization of reductions

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2010-04-21 13:08 -------
Wade-through-the-code dump:

gfc_trans_assignment_1 gets

  make_esss:esss(:)
  (+ make_esss:esss(:) _gfortran_sum_r8[[(((* make_esss:ix(: ,
__convert_i4_i8[[((make_esss:e_x(FULL)))]]) make_esss:iyz(: ,
__convert_i4_i8[[((make_esss:ii_ivec(FULL)))]]))) (_8) ((arg not-present)))]])

the first issue is that while we can properly scalarize

subroutine test0(esss,Ix,Iyz)
  real(kind=kind(1.0d0)), intent(out) :: esss
  real(kind=kind(1.0d0)), dimension(:) :: Ix,Iyz
  esss = sum(Ix * Iyz, 0)
end subroutine

we can't handle

subroutine test1(esss,Ix,Iyz)
  real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
  real(kind=kind(1.0d0)), dimension(:,:) :: Ix,Iyz
  esss = sum(Ix * Iyz, 0)
end subroutine

as gfc_conv_intrinsic_function does not handle expr->rank > 0 for
inline expansion.

The second issue is that for

subroutine test0(esss,Ix,Iyz, e_x, ii_ivec)
  real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
  real(kind=kind(1.0d0)), dimension(:) :: Ix,Iyz
  integer(kind=kind(1)), dimension(:) :: e_x,ii_ivec
  esss = Ix(e_x) * Iyz(ii_ivec)
end subroutine

we create temporaries for e_x and ii_ivec.  Even for

subroutine test0(esss,Ix, e_x)
  real(kind=kind(1.0d0)), dimension(:), intent(out) :: esss
  real(kind=kind(1.0d0)), dimension(:) :: Ix
  integer(kind=kind(1)), dimension(:) :: e_x
  esss = Ix(e_x)
end subroutine


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Scalarization of reductions |Scalarization of reductions
                   |with Fortran array          |
                   |expressions                 |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43829