[patch, fortran] Fix PR 66089, ICE (plus wrong code) in dependency handling

[patch, fortran] Fix PR 66089, ICE (plus wrong code) in dependency handling

[Thomas Koenig]

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Hello world,

the attached patch fixes a 7/8/9 regression where dependency checking
was for class arrays and a scalar value was mishandled when the
dependency happened in an elemental function.

There was an ICE for the test case which is handled by
fixing up the class refs in gfc_walk_variable_expr.
Once this was gone, a wrong-code issue appeared which was fixed
by the part in gfc_scalar_elemental_arg_saved_as_reference
(is that the longest function name in gfortran?).

Regression-tested. OK for all affected branches?

Regards

	Thomas

2019-03-06  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/66089
	* trans-array.c (gfc_scalar_elemental_arg_saved_as_reference):
	Return false if a scalar tempoary is needed.
	(gfc_walk_variable_expr): Fix up class refs.

2019-03-06  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/66089
	* gfortran.dg/dependency_53.f90: New test.

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Index: trans-array.c
===================================================================
--- trans-array.c	(Revision 269260)
+++ trans-array.c	(Arbeitskopie)
@@ -2699,6 +2699,9 @@ gfc_scalar_elemental_arg_saved_as_reference (gfc_s
   if (ss_info->type != GFC_SS_REFERENCE)
     return false;
 
+  if (ss_info->data.scalar.needs_temporary)
+    return false;
+
   /* If the actual argument can be absent (in other words, it can
      be a NULL reference), don't try to evaluate it; pass instead
      the reference directly.  */
@@ -10515,6 +10518,8 @@ gfc_walk_variable_expr (gfc_ss * ss, gfc_expr * ex
 {
   gfc_ref *ref;
 
+  gfc_fix_class_refs (expr);
+
   for (ref = expr->ref; ref; ref = ref->next)
     if (ref->type == REF_ARRAY && ref->u.ar.type != AR_ELEMENT)
       break;

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! { dg-do run }
! PR fortran/66089 - used to ICE and, after that ICE was fixed,
! gave wrong results.
  type :: t
    integer :: c
  end type t

  class(t), dimension(:), allocatable :: b,c

  allocate (b(5), source=t(7))
  allocate(c(5), source=t(13))
  c = plus(c(1), b)
  if (any(c%c /= 20)) call abort
  c = t(13)
  c = plus(b, c(1))
  if (any(c%c /= 20)) call abort
contains

  elemental function plus(lhs, rhs)
    class(t), intent(in) :: lhs, rhs
    type(t)             :: plus
    plus%c = lhs%c + rhs%c
  end function plus

end

Re: [patch, fortran] Fix PR 66089, ICE (plus wrong code) in dependency handling

[Bernhard Reutner-Fischer]

On 6 March 2019 19:49:59 CET, Thomas Koenig <tkoenig@netcologne.de> wrote:
>Hello world,
>
>the attached patch fixes a 7/8/9 regression where dependency checking
>was for class arrays and a scalar value was mishandled when the
>dependency happened in an elemental function.
>
>There was an ICE for the test case which is handled by
>fixing up the class refs in gfc_walk_variable_expr.
>Once this was gone, a wrong-code issue appeared which was fixed
>by the part in gfc_scalar_elemental_arg_saved_as_reference
>(is that the longest function name in gfortran?).
>
>Regression-tested. OK for all affected branches?

Please change call abort to stop N in the test?

>	PR fortran/66089
>	* gfortran.dg/dependency_53.f90: New test.

Re: [patch, fortran] Fix PR 66089, ICE (plus wrong code) in dependency handling

[Thomas Koenig]

Am 08.03.19 um 08:04 schrieb Bernhard Reutner-Fischer:
> Please change call abort to stop N in the test?

Done.

Anything else?  OK for trunk?

Regards

	Thomas

Re: [patch, fortran] Fix PR 66089, ICE (plus wrong code) in dependency handling

[Dominique d'Humières]

Hi Thomas,

> Anything else? …

Yes, the tests gfortran.dg/assumed_type_2.f90 and gfortran.dg/no_arg_check_2.f90 fail:

FAIL: gfortran.dg/assumed_type_2.f90   -O   scan-tree-dump-times original "sub_array_assumed \\\\(D" 3 (found 4 times)
FAIL: gfortran.dg/assumed_type_2.f90   -O   scan-tree-dump-times original "sub_array_assumed \\\\(\\\\(struct t1.0:. .\\\\) array_class_t1_ptr._data.data\\\\);" 1 (found 0 times)

FAIL: gfortran.dg/no_arg_check_2.f90   -O   scan-tree-dump-times original "sub_array_assumed \\\\(D" 3 (found 4 times)
FAIL: gfortran.dg/no_arg_check_2.f90   -O   scan-tree-dump-times original "sub_array_assumed \\\\(\\\\(struct t1.0:. .\\\\) array_class_t1_ptr._data.data\\\\);" 1 (found 0 times)

TIA

Dominique