[Bug fortran/43243] New: [4.5 Regression] Missing array temp for DT with pointer component

[Bug fortran/43243] New: [4.5 Regression] Missing array temp for DT with pointer component

[burnus at gcc dot gnu dot org]

Follow up to PR 43173 - but this time for derived types.

In the following calls, if the ultimate component is a non-pointer and all
previous part-refs have no vector subscripts, there is no need for packing the
argument (i.e. creating a temporary).

However, if the ultimate component is a pointer, one needs to pack as the test
case also shows.

Correctness test fails with
  4.5.0 20100218 (experimental) [trunk revision 156860]
  4.5.0 20100303 (experimental)
but works with
  4.4.2 [gcc-4_4-branch revision 155966]
  4.3.4 [gcc-4_3-branch revision 152973]



module m
  type t
    integer, allocatable :: a(:)
    integer, pointer :: b(:)
    integer :: c(5)
  end type t
end module m

subroutine foo(a,d,e,n)
  use m
  implicit none
  integer :: n
  type(t) :: a
  type(t), allocatable :: d(:)
  type(t), pointer :: e(:)
  call bar(   a%a) ! OK - no array temp needed
  call bar(   a%c) ! OK - no array temp needed

  call bar(   a%a(1:n)) ! Missed: No pack needed
  call bar(   a%b(1:n)) ! OK: pack needed
  call bar(   a%c(1:n)) ! Missed: No pack needed

  call bar(d(1)%a(1:n)) ! Missed: No pack needed
  call bar(d(1)%b(1:n)) ! OK: pack needed
  call bar(d(1)%c(1:n)) ! Missed: No pack needed

  call bar(e(1)%a(1:n)) ! Missed: No pack needed
  call bar(e(1)%b(1:n)) ! OK: pack needed
  call bar(e(1)%c(1:n)) ! Missed: No pack needed
end subroutine foo

use m
implicit none
integer :: i
integer, target :: z(6)
type(t) :: y

z = [(i, i=1,6)]
y%b => z(::2)
call bar(y%b)
end

subroutine bar(x)
  integer :: x(1:*)
  print *, x(1:3)
  if (any (x(1:3) /= [1,3,5])) call abort ()
end subroutine bar


-- 
           Summary: [4.5 Regression] Missing array temp for DT with pointer
                    component
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Keywords: wrong-code, missed-optimization
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: burnus at gcc dot gnu dot org
OtherBugsDependingO 42361
             nThis:


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Missing array temp for DT with pointer component

[rguenth at gcc dot gnu dot org]

-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Missing array temp for DT with pointer component

[paul dot richard dot thomas at gmail dot com]

------- Comment #1 from paul dot richard dot thomas at gmail dot com  2010-03-03 15:53 -------
Subject: Re:  [4.5 Regression] Missing array temp for DT 
        with pointer component

Yet another in the series :-)   I hope that it is the last...

This bootstraps and regtests on RHEL5.2/x86_64 - OK for trunk?

Paul

2010-03-03  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/43243
        * trans-array.c (gfc_conv_array_parameter): Contiguous refs to
        allocatable ultimate components do not need temporaries, whilst
        ultimate pointer components do.

2010-03-03  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/43243
        * gfortran.dg/internal_pack_12.f90: New test.


------- Comment #2 from paul dot richard dot thomas at gmail dot com  2010-03-03 15:53 -------
Created an attachment (id=20010)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=20010&action=view)


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[burnus at gcc dot gnu dot org]

------- Comment #3 from burnus at gcc dot gnu dot org  2010-03-03 15:53 -------
As it might have not been completely clear from comment 0:

  type t
    [...]
    integer, pointer :: b(:)
  end type
  type(t) :: y
  y%b => z(::2)
  call bar(y%b) ! <<< WRONG-CODE: Here a temporary is missing

Without the temporary, [1,2,3] instead of [1,3,5] is passed to "bar" and thus
the example fails with a call to ABORT. (The rest of example illustrates a
missed optimization, which is not a regression.)


-- 

burnus at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |4.5.0
      Known to work|                            |4.3.5 4.4.3
           Priority|P3                          |P4
            Summary|[4.5 Regression] Missing    |[4.5 Regression] Wrong-code
                   |array temp for DT with      |due to missing array temp
                   |pointer component           |for DT with pointer
                   |                            |component


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[paul dot richard dot thomas at gmail dot com]

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------- Comment #4 from paul dot richard dot thomas at gmail dot com  2010-03-03 16:15 -------
Subject: Re:  [4.5 Regression] Wrong-code due to missing 
        array temp for DT with pointer component

Tobias,

Don't worry, I got it:-)

The patch fixes both problems.

Cheers

Paul

On Wed, Mar 3, 2010 at 4:53 PM, burnus at gcc dot gnu dot org
<gcc-bugzilla@gcc.gnu.org> wrote:
>
>
> ------- Comment #3 from burnus at gcc dot gnu dot org  2010-03-03 15:53 -------
> As it might have not been completely clear from comment 0:
>
>  type t
>    [...]
>    integer, pointer :: b(:)
>  end type
>  type(t) :: y
>  y%b => z(::2)
>  call bar(y%b) ! <<< WRONG-CODE: Here a temporary is missing
>
> Without the temporary, [1,2,3] instead of [1,3,5] is passed to "bar" and thus
> the example fails with a call to ABORT. (The rest of example illustrates a
> missed optimization, which is not a regression.)
>
>
> --
>
> burnus at gcc dot gnu dot org changed:
>
>           What    |Removed                     |Added
> ----------------------------------------------------------------------------
>      Known to fail|                            |4.5.0
>      Known to work|                            |4.3.5 4.4.3
>           Priority|P3                          |P4
>            Summary|[4.5 Regression] Missing    |[4.5 Regression] Wrong-code
>                   |array temp for DT with      |due to missing array temp
>                   |pointer component           |for DT with pointer
>                   |                            |component
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243
>
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug, or are watching someone who is.
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[burnus at net-b dot de]

------- Comment #5 from burnus at net-b dot de  2010-03-03 16:59 -------
Subject: Re:  [4.5 Regression] Missing array temp for DT
        with pointer component

On 03/03/2010 04:53 PM, Paul Richard Thomas wrote:
> Yet another in the series :-)   I hope that it is the last...
>   

So do I - especially with regards to regressions. Regarding temporaries:
I was compiling some programs with the patched gfortran and the number
of created temporaries is quite low - and I think no low-lying fruits
are left. There are some cases of assignments for which middle-end array
support were helpful (hint, hint) and some other cases with MATMUL and
assignments which could be solved in the front end. (And two of the
programs here could gain some performance, if they would move to TR
15581; without the compiler has unnecessarily to assume aliasing. But as
both do not dare to drop support for F95-only compilers, yet, ...)

By the way, for RESHAPE gfortran generates temporaries what could be
avoided if RESHAPE wouldn't deallocate - that's another candidate to fix
after the new array descriptor gained a "bool allocated" component ...
cf. PR 32512.

> This bootstraps and regtests on RHEL5.2/x86_64 - OK for trunk?
>   
OK. Thanks a lot for the patch!

Tobias

> 2010-03-03  Paul Thomas  <pault@gcc.gnu.org>
>
> 	PR fortran/43243
> 	* trans-array.c (gfc_conv_array_parameter): Contiguous refs to
> 	allocatable ultimate components do not need temporaries, whilst
> 	ultimate pointer components do.
>
> 2010-03-03  Paul Thomas  <pault@gcc.gnu.org>
>
> 	PR fortran/43243
> 	* gfortran.dg/internal_pack_12.f90: New test.
>   


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[pault at gcc dot gnu dot org]

------- Comment #6 from pault at gcc dot gnu dot org  2010-03-03 17:50 -------
Subject: Bug 43243

Author: pault
Date: Wed Mar  3 17:49:53 2010
New Revision: 157199

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=157199
Log:
2010-03-03  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/43243
        * trans-array.c (gfc_conv_array_parameter): Contiguous refs to
        allocatable ultimate components do not need temporaries, whilst
        ultimate pointer components do.

2010-03-03  Paul Thomas  <pault@gcc.gnu.org>

        PR fortran/43243
        * gfortran.dg/internal_pack_12.f90: New test.

Added:
    trunk/gcc/testsuite/gfortran.dg/internal_pack_12.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-array.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[pault at gcc dot gnu dot org]

------- Comment #7 from pault at gcc dot gnu dot org  2010-03-03 17:53 -------
Fixed on trunk and.... yes, thanks for the report!

Cheers

Paul


-- 

pault at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[hjl dot tools at gmail dot com]

------- Comment #8 from hjl dot tools at gmail dot com  2010-03-13 16:52 -------
gfortran.dg/internal_pack_12.f90 failed with gcc 4.4 branch
as of 2010-03-13. Is this a regression on 4.4 branch?


-- 

hjl dot tools at gmail dot com changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.5 Regression] Wrong-code due to missing array temp for DT with pointer component

[paul dot richard dot thomas at gmail dot com]

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------- Comment #9 from paul dot richard dot thomas at gmail dot com  2010-03-13 17:26 -------
Subject: Re:  [4.5 Regression] Wrong-code due to missing 
        array temp for DT with pointer component

HJ,

Thanks for doing all this backporting of the testcases.

As it happens, I have been leaving 4.4 alone, since causing all manner
of problems a few weeks ago.

I cannot check 4.4 until tomorrow night; I only have trunk on my
laptop.  However, I will certainly take a look then.

Thanks again

Paul

On Sat, Mar 13, 2010 at 5:52 PM, hjl dot tools at gmail dot com
<gcc-bugzilla@gcc.gnu.org> wrote:
>
>
> ------- Comment #8 from hjl dot tools at gmail dot com  2010-03-13 16:52 -------
> gfortran.dg/internal_pack_12.f90 failed with gcc 4.4 branch
> as of 2010-03-13. Is this a regression on 4.4 branch?
>
>
> --
>
> hjl dot tools at gmail dot com changed:
>
>           What    |Removed                     |Added
> ----------------------------------------------------------------------------
>             Status|RESOLVED                    |UNCONFIRMED
>         Resolution|FIXED                       |
>
>
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243
>
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug, or are watching someone who is.
>


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.4 Regression ?] Wrong-code due to missing array temp for DT with pointer component

[pault at gcc dot gnu dot org]

------- Comment #10 from pault at gcc dot gnu dot org  2010-03-14 06:27 -------
Will check this out as soon as I am back at base.

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[4.5 Regression] Wrong-code |[4.4 Regression ?] Wrong-
                   |due to missing array temp   |code due to missing array
                   |for DT with pointer         |temp for DT with pointer
                   |component                   |component


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243

[Bug fortran/43243] [4.4 Regression ?] Wrong-code due to missing array temp for DT with pointer component

[pault at gcc dot gnu dot org]

------- Comment #11 from pault at gcc dot gnu dot org  2010-03-15 17:23 -------
(In reply to comment #10)
> Will check this out as soon as I am back at base.

HJ,

4.4 does not deal with the original problem and so still produces the
unnecessary temporaries.

from the end of internal_pack12.f90...

! { dg-final { scan-tree-dump-times "unpack" 4 "original" } }
! { dg-final { cleanup-tree-dump "original" } }
! { dg-final { cleanup-modules "m" } }

[pault@localhost pr43243]# /irun4.4/bin/gfortran -static -fdump-tree-original
/svn/trunk/gcc/testsuite/gfortran.dg/internal_pack_12.f90
[pault@localhost pr43243]# grep unpack *nal
        _gfortran_internal_unpack (&a->a, D.1552);
        _gfortran_internal_unpack (&parm.0, D.1556);
        _gfortran_internal_unpack (&parm.1, D.1561);
        _gfortran_internal_unpack (&parm.2, D.1566);
        _gfortran_internal_unpack (&parm.3, D.1570);
        _gfortran_internal_unpack (&parm.4, D.1575);
        _gfortran_internal_unpack (&parm.5, D.1580);
        _gfortran_internal_unpack (&parm.6, D.1584);
        _gfortran_internal_unpack (&parm.7, D.1589);
        _gfortran_internal_unpack (&parm.8, D.1594);
        _gfortran_internal_unpack (&parm.9, D.1598);
          _gfortran_internal_unpack (&y.b, D.1845);

That's why it's failing. I suggest strongly that the test not be backported to
4.4.

I am resolving this as INVALID although I am a bit unhappy about marking a
sensible, precautionary PR in this way.

Thanks for the report nevertheless!

Paul


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43243