Re: [PATCH 08/11] fortran: array descriptor: Add accessors for the dim field

Hello Mikael,

This is well consistent with its predecessors and LGTM.

Thanks

Paul

On Sat, 1 Nov 2025 at 21:15, Mikael Morin <[email protected]> wrote:
>
> From: Mikael Morin <[email protected]>
>
> Regression tested on powerpc64le-unknown-linux-gnu.  OK for master?
>
> -- >8 --
>
> Add accessor functions to get or set the value of the elements of the dim
> field of array descriptors, and remove from the public API the function
> giving direct acces to the elements.
>
> There are already accessors for the lower bound, upper bound and stride
> subfields.  But there is one place where the elements are copied as a whole
> without looking at the subfields, and using the subfields accessors for that
> case would be more noisy and less efficient.
>
> gcc/fortran/ChangeLog:
>
>         * trans-descriptor.cc (gfc_conv_descriptor_dimension): Make static
>         and rename ...
>         (conv_descriptor_dimension): ... to this.
>         (gfc_conv_descriptor_subfield): Update caller.
>         (gfc_conv_descriptor_dimension_get,
>         gfc_conv_descriptor_dimension_set): New functions.
>         * trans-descriptor.h (gfc_conv_descriptor_dimension): Remove
>         declaration.
>         (gfc_conv_descriptor_dimension_get,
>         gfc_conv_descriptor_dimension_set): New declarations.
>         * trans-array.cc (gfc_conv_array_parameter): Use
>         gfc_conv_descriptor_dimension_get to get an element of the dim
>         field, und gfc_conv_descriptor_dimension_set to set it.
> ---
>  gcc/fortran/trans-array.cc      |  9 +++---
>  gcc/fortran/trans-descriptor.cc | 50 +++++++++++++++++++++++++++++++--
>  gcc/fortran/trans-descriptor.h  |  5 +++-
>  3 files changed, 55 insertions(+), 9 deletions(-)
>
> diff --git a/gcc/fortran/trans-array.cc b/gcc/fortran/trans-array.cc
> index 1254eae8ea1..bd9f66a34d6 100644
> --- a/gcc/fortran/trans-array.cc
> +++ b/gcc/fortran/trans-array.cc
> @@ -9075,11 +9075,10 @@ gfc_conv_array_parameter (gfc_se *se, gfc_expr *expr, bool g77,
>
>               for (int i = 0; i < expr->rank; i++)
>                 {
> -                 old_field = gfc_conv_descriptor_dimension (old_desc,
> -                       gfc_rank_cst[get_array_ref_dim_for_loop_dim (ss, i)]);
> -                 new_field = gfc_conv_descriptor_dimension (new_desc,
> -                       gfc_rank_cst[i]);
> -                 gfc_add_modify (&se->pre, new_field, old_field);
> +                 int idx = get_array_ref_dim_for_loop_dim (ss, i);
> +                 old_field = gfc_conv_descriptor_dimension_get (old_desc, idx);
> +                 gfc_conv_descriptor_dimension_set (&se->pre, new_desc, i,
> +                                                    old_field);
>                 }
>
>               if (flag_coarray == GFC_FCOARRAY_LIB
> diff --git a/gcc/fortran/trans-descriptor.cc b/gcc/fortran/trans-descriptor.cc
> index c3aaacd7514..5f7b9955ad0 100644
> --- a/gcc/fortran/trans-descriptor.cc
> +++ b/gcc/fortran/trans-descriptor.cc
> @@ -398,8 +398,11 @@ gfc_get_descriptor_dimension (tree desc)
>  }
>
>
> -tree
> -gfc_conv_descriptor_dimension (tree desc, tree dim)
> +/* Return a reference to the array access information of the (zero-based)
> +   dimension DIM of the array descriptor DESC.  */
> +
> +static tree
> +conv_descriptor_dimension (tree desc, tree dim)
>  {
>    tree tmp;
>
> @@ -408,6 +411,47 @@ gfc_conv_descriptor_dimension (tree desc, tree dim)
>    return gfc_build_array_ref (tmp, dim, NULL_TREE, true);
>  }
>
> +/* Return the value of the array access information of the (zero-based)
> +   dimension DIM of the array represented by descriptor DESC.  */
> +
> +tree
> +gfc_conv_descriptor_dimension_get (tree desc, tree dim)
> +{
> +  return conv_descriptor_dimension (desc, dim);
> +}
> +
> +/* Return the value of the array access information of the (zero-based)
> +   dimension DIM of the array represented by descriptor DESC.  */
> +
> +tree
> +gfc_conv_descriptor_dimension_get (tree desc, int dim)
> +{
> +  return gfc_conv_descriptor_dimension_get (desc, gfc_rank_cst[dim]);
> +}
> +
> +/* Add code to BLOCK setting to VALUE the array access information of the
> +   (zero-based) dimension DIM of the array descriptor DESC.  */
> +
> +void
> +gfc_conv_descriptor_dimension_set (stmtblock_t *block, tree desc, tree dim,
> +                                  tree value)
> +{
> +  location_t loc = input_location;
> +  tree t = conv_descriptor_dimension (desc, dim);
> +  gfc_add_modify_loc (loc, block, t,
> +                     fold_convert_loc (loc, TREE_TYPE (t), value));
> +}
> +
> +/* Add code to BLOCK setting to VALUE the array access information of the
> +   (zero-based) dimension DIM of the array descriptor DESC.  */
> +
> +void
> +gfc_conv_descriptor_dimension_set (stmtblock_t *block, tree desc, int dim,
> +                                  tree value)
> +{
> +  gfc_conv_descriptor_dimension_set (block, desc, gfc_rank_cst[dim], value);
> +}
> +
>
>  tree
>  gfc_conv_descriptor_token (tree desc)
> @@ -423,7 +467,7 @@ gfc_conv_descriptor_token (tree desc)
>  static tree
>  gfc_conv_descriptor_subfield (tree desc, tree dim, unsigned field_idx)
>  {
> -  tree tmp = gfc_conv_descriptor_dimension (desc, dim);
> +  tree tmp = conv_descriptor_dimension (desc, dim);
>    tree field = gfc_advance_chain (TYPE_FIELDS (TREE_TYPE (tmp)), field_idx);
>    gcc_assert (field != NULL_TREE);
>
> diff --git a/gcc/fortran/trans-descriptor.h b/gcc/fortran/trans-descriptor.h
> index 3ad9b660052..8c28eb1c54a 100644
> --- a/gcc/fortran/trans-descriptor.h
> +++ b/gcc/fortran/trans-descriptor.h
> @@ -21,7 +21,6 @@ along with GCC; see the file COPYING3.  If not see
>
>
>  tree gfc_get_descriptor_dimension (tree);
> -tree gfc_conv_descriptor_dimension (tree, tree);
>  tree gfc_conv_descriptor_token (tree);
>
>  tree gfc_conv_descriptor_data_get (tree);
> @@ -33,6 +32,8 @@ tree gfc_conv_descriptor_rank_get (tree);
>  tree gfc_conv_descriptor_type_get (tree);
>  tree gfc_conv_descriptor_span_get (tree);
>
> +tree gfc_conv_descriptor_dimension_get (tree desc, tree dim);
> +tree gfc_conv_descriptor_dimension_get (tree desc, int dim);
>  tree gfc_conv_descriptor_stride_get (tree, tree);
>  tree gfc_conv_descriptor_lbound_get (tree, tree);
>  tree gfc_conv_descriptor_ubound_get (tree, tree);
> @@ -48,6 +49,8 @@ void gfc_conv_descriptor_type_set (stmtblock_t *, tree, tree);
>  tree gfc_conv_descriptor_type_set (tree, tree);
>  tree gfc_conv_descriptor_type_set (tree, int);
>  void gfc_conv_descriptor_span_set (stmtblock_t *, tree, tree);
> +void gfc_conv_descriptor_dimension_set (stmtblock_t *, tree, tree, tree);
> +void gfc_conv_descriptor_dimension_set (stmtblock_t *, tree, int, tree);
>  void gfc_conv_descriptor_stride_set (stmtblock_t *, tree, tree, tree);
>  void gfc_conv_descriptor_lbound_set (stmtblock_t *, tree, tree, tree);
>  void gfc_conv_descriptor_ubound_set (stmtblock_t *, tree, tree, tree);
> --
> 2.51.0
>