[gcc(refs/users/mikael/heads/refactor_descriptor_v291.01)] fortran: array descriptor: Move dtype constructor generation [PR122521]

https://gcc.gnu.org/g:4217853a871f713f806cbe5be1cb6c8c40dc7097

commit 4217853a871f713f806cbe5be1cb6c8c40dc7097
Author: Mikael Morin <[email protected]>
Date:   Wed Nov 12 21:09:32 2025 +0100

    fortran: array descriptor: Move dtype constructor generation [PR122521]
    
    Move the constructor generation for the dtype field of a descriptor to a
    separate function.  This avoids leaking the layout order of the dtype fields
    out of trans-descriptor.cc.
    
            PR fortran/122521
    
    gcc/fortran/ChangeLog:
    
            * trans-types.cc (gfc_get_dtype_rank_type): Move constructor
            generation ...
            * trans-descriptor.cc (gfc_build_dtype_constructor): ... here as a
            new function.
            * trans-descriptor.h (gfc_build_dtype_constructor): New declaration.

Diff:
---
 gcc/fortran/trans-descriptor.cc | 38 ++++++++++++++++++++++++++++++++++++++
 gcc/fortran/trans-descriptor.h  |  2 ++
 gcc/fortran/trans-types.cc      | 33 +--------------------------------
 3 files changed, 41 insertions(+), 32 deletions(-)

diff --git a/gcc/fortran/trans-descriptor.cc b/gcc/fortran/trans-descriptor.cc
index 6156f4e2db1e..e4ff96fff671 100644
--- a/gcc/fortran/trans-descriptor.cc
+++ b/gcc/fortran/trans-descriptor.cc
@@ -624,6 +624,44 @@ gfc_get_descriptor_offsets_for_info (const_tree desc_type, tree *data_off,
 /* Array descriptor higher level routines.
  ******************************************************************************/
 
+/* Return a constructor for a descriptor dtype with the caracteristics given by
+   the arguments.  */
+
+tree
+gfc_build_dtype_constructor (tree size, int type, int rank)
+{
+  tree field;
+  vec<constructor_elt, va_gc> *v = NULL;
+
+  gcc_assert (size);
+
+  STRIP_NOPS (size);
+  size = fold_convert (size_type_node, size);
+  tree dtype_type_node = get_dtype_type_node ();
+  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
+			     GFC_DTYPE_ELEM_LEN);
+  CONSTRUCTOR_APPEND_ELT (v, field,
+			  fold_convert (TREE_TYPE (field), size));
+  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
+			     GFC_DTYPE_VERSION);
+  CONSTRUCTOR_APPEND_ELT (v, field,
+			  build_zero_cst (TREE_TYPE (field)));
+
+  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
+			     GFC_DTYPE_RANK);
+  if (rank >= 0)
+    CONSTRUCTOR_APPEND_ELT (v, field,
+			    build_int_cst (TREE_TYPE (field), rank));
+
+  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
+			     GFC_DTYPE_TYPE);
+  CONSTRUCTOR_APPEND_ELT (v, field,
+			  build_int_cst (TREE_TYPE (field), type));
+
+  return build_constructor (dtype_type_node, v);
+}
+
+
 /* Build a null array descriptor constructor.  */
 
 tree
diff --git a/gcc/fortran/trans-descriptor.h b/gcc/fortran/trans-descriptor.h
index 081bb45ef074..7a206e2a4b21 100644
--- a/gcc/fortran/trans-descriptor.h
+++ b/gcc/fortran/trans-descriptor.h
@@ -53,6 +53,8 @@ void gfc_conv_descriptor_lbound_set (stmtblock_t *, tree, tree, tree);
 void gfc_conv_descriptor_ubound_set (stmtblock_t *, tree, tree, tree);
 void gfc_conv_descriptor_token_set (stmtblock_t *block, tree desc, tree value);
 
+tree gfc_build_dtype_constructor (tree, int, int);
+
 /* Build expressions for accessing components of an array descriptor.  */
 void gfc_get_descriptor_offsets_for_info (const_tree, tree *, tree *, tree *,
 					  tree *, tree *, tree *, tree *,
diff --git a/gcc/fortran/trans-types.cc b/gcc/fortran/trans-types.cc
index ea4395c67dd7..4cc63c4f64d4 100644
--- a/gcc/fortran/trans-types.cc
+++ b/gcc/fortran/trans-types.cc
@@ -1709,10 +1709,6 @@ gfc_get_dtype_rank_type (int rank, tree etype)
   tree ptype;
   tree size;
   int n;
-  tree tmp;
-  tree dtype;
-  tree field;
-  vec<constructor_elt, va_gc> *v = NULL;
 
   ptype = etype;
   while (TREE_CODE (etype) == POINTER_TYPE
@@ -1784,34 +1780,7 @@ gfc_get_dtype_rank_type (int rank, tree etype)
       break;
     }
 
-  gcc_assert (size);
-
-  STRIP_NOPS (size);
-  size = fold_convert (size_type_node, size);
-  tmp = get_dtype_type_node ();
-  field = gfc_advance_chain (TYPE_FIELDS (tmp),
-			     GFC_DTYPE_ELEM_LEN);
-  CONSTRUCTOR_APPEND_ELT (v, field,
-			  fold_convert (TREE_TYPE (field), size));
-  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
-			     GFC_DTYPE_VERSION);
-  CONSTRUCTOR_APPEND_ELT (v, field,
-			  build_zero_cst (TREE_TYPE (field)));
-
-  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
-			     GFC_DTYPE_RANK);
-  if (rank >= 0)
-    CONSTRUCTOR_APPEND_ELT (v, field,
-			    build_int_cst (TREE_TYPE (field), rank));
-
-  field = gfc_advance_chain (TYPE_FIELDS (dtype_type_node),
-			     GFC_DTYPE_TYPE);
-  CONSTRUCTOR_APPEND_ELT (v, field,
-			  build_int_cst (TREE_TYPE (field), n));
-
-  dtype = build_constructor (tmp, v);
-
-  return dtype;
+  return gfc_build_dtype_constructor (size, n, rank);
 }