Re: [PATCH, OpenACC] Make reduction arguments addressable

[Chung-Lin Tang]

On 2016/6/1 09:38 PM, Jakub Jelinek wrote:
>>      construct_clauses.lists[OMP_LIST_REDUCTION] = NULL;
>> >        oacc_clauses = gfc_trans_omp_clauses (&block, &construct_clauses,
>> >                                        code->loc);
>> > +      for (tree c = oacc_clauses; c; c = OMP_CLAUSE_CHAIN (c))
>> > +  if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_ASYNC)
>> > +    {
>> > +      for (c = oacc_clauses; c; c = OMP_CLAUSE_CHAIN (c))
>> > +        if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
>> > +            && DECL_P (OMP_CLAUSE_DECL (c)))
>> > +          TREE_ADDRESSABLE (OMP_CLAUSE_DECL (c)) = 1;
>> > +      break;
>> > +    }
>> >      }
> These 2 look wrong to me.  1) you really don't need to walk all the clauses
> to find if there is OMP_CLAUSE_ASYNC, you can just test the
> async field of struct gfc_omp_clauses.  And, 2) is there any reason why you
> can't just do this in gfc_trans_omp_clauses instead, when crating
> OMP_CLAUSE_REDUCTION if clauses->async is set?  Or are there some cases
> where on OpenACC constructs you don't want to do this?

Thanks for reminding, I didn't notice there was such a gfc_omp_clauses->async 
field.

Here's a much more succinct patch that does it inside gfc_trans_omp_clauses.
Again re-tested gfortran and libgomp without regressions.
Is this and the C/C++ patches (and the new testsuite cases) okay for trunk?

Thanks,
Chung-Lin

        fortran/
        * trans-openmp.c (gfc_trans_omp_clauses): Mark OpenACC reduction
        arguments as addressable when async clause exists.


Index: trans-openmp.c
===================================================================
--- trans-openmp.c      (revision 236845)
+++ trans-openmp.c      (working copy)
@@ -1748,6 +1748,12 @@ gfc_trans_omp_clauses (stmtblock_t *block, gfc_omp
        {
        case OMP_LIST_REDUCTION:
          omp_clauses = gfc_trans_omp_reduction_list (n, omp_clauses, where);
+         /* An OpenACC async clause indicates the need to set reduction
+            arguments addressable, to allow asynchronous copy-out.  */
+         if (clauses->async)
+           for (c = omp_clauses; c; c = OMP_CLAUSE_CHAIN (c))
+             if (DECL_P (OMP_CLAUSE_DECL (c)))
+               TREE_ADDRESSABLE (OMP_CLAUSE_DECL (c)) = 1;
          break;
        case OMP_LIST_PRIVATE:
          clause_code = OMP_CLAUSE_PRIVATE;