[gcc(refs/users/mikael/heads/refactor_descriptor_v291.01)] Extraction gfc_shift_descriptor

https://gcc.gnu.org/g:ef98d635fa01610e145d11fbc3b4691436647b16

commit ef98d635fa01610e145d11fbc3b4691436647b16
Author: Mikael Morin <[email protected]>
Date:   Wed Jul 23 14:59:35 2025 +0200

    Extraction gfc_shift_descriptor

Diff:
---
 gcc/fortran/trans-descriptor.cc | 32 ++++++++++++++++++++++++++++++++
 gcc/fortran/trans-descriptor.h  |  2 ++
 gcc/fortran/trans-expr.cc       | 39 ++-------------------------------------
 3 files changed, 36 insertions(+), 37 deletions(-)

diff --git a/gcc/fortran/trans-descriptor.cc b/gcc/fortran/trans-descriptor.cc
index 59975d870d5a..bc76d0c4a8e3 100644
--- a/gcc/fortran/trans-descriptor.cc
+++ b/gcc/fortran/trans-descriptor.cc
@@ -1288,3 +1288,35 @@ gfc_set_subarray_descriptor (stmtblock_t *block, tree descr, tree value,
       gfc_conv_descriptor_offset_set (block, descr, tmp);
     }
 }
+
+
+void
+gfc_shift_descriptor (stmtblock_t *block, tree descr, int rank,
+		      tree lbound[GFC_MAX_DIMENSIONS],
+		      tree ubound[GFC_MAX_DIMENSIONS])
+{
+  tree size = gfc_index_one_node;
+  tree offset = gfc_index_zero_node;
+  for (int n = 0; n < rank; n++)
+    {
+      tree tmp = gfc_conv_descriptor_ubound_get (descr, gfc_rank_cst[n]);
+      tmp = fold_build2_loc (input_location, PLUS_EXPR,
+			     gfc_array_index_type, tmp,
+			     gfc_index_one_node);
+      gfc_conv_descriptor_ubound_set (block, descr, gfc_rank_cst[n], tmp);
+      gfc_conv_descriptor_lbound_set (block, descr, gfc_rank_cst[n],
+				      gfc_index_one_node);
+      size = gfc_evaluate_now (size, block);
+      offset = fold_build2_loc (input_location, MINUS_EXPR,
+				gfc_array_index_type, offset, size);
+      offset = gfc_evaluate_now (offset, block);
+      tmp = fold_build2_loc (input_location, MINUS_EXPR,
+			     gfc_array_index_type, ubound[n], lbound[n]);
+      tmp = fold_build2_loc (input_location, PLUS_EXPR,
+			     gfc_array_index_type, tmp, gfc_index_one_node);
+      size = fold_build2_loc (input_location, MULT_EXPR,
+			      gfc_array_index_type, size, tmp);
+    }
+
+  gfc_conv_descriptor_offset_set (block, descr, offset);
+}
diff --git a/gcc/fortran/trans-descriptor.h b/gcc/fortran/trans-descriptor.h
index f9360930d1df..65e1a193d204 100644
--- a/gcc/fortran/trans-descriptor.h
+++ b/gcc/fortran/trans-descriptor.h
@@ -90,6 +90,8 @@ void gfc_conv_shift_descriptor (stmtblock_t *, tree, int);
 void gfc_conv_shift_descriptor (stmtblock_t *, tree, const gfc_array_ref &);
 void gfc_conv_shift_descriptor (stmtblock_t *, tree, tree, int, tree);
 void gfc_set_subarray_descriptor (stmtblock_t *, tree, tree, gfc_expr *, gfc_expr *);
+void gfc_shift_descriptor (stmtblock_t *, tree, int, tree [GFC_MAX_DIMENSIONS],
+			   tree [GFC_MAX_DIMENSIONS]);
 
 void gfc_set_descriptor_from_scalar_class (stmtblock_t *, tree, tree, gfc_expr *);
 void gfc_set_descriptor_from_scalar (stmtblock_t *, tree, tree, symbol_attribute,
diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
index f4a816315c95..6f5a3308b76c 100644
--- a/gcc/fortran/trans-expr.cc
+++ b/gcc/fortran/trans-expr.cc
@@ -5463,7 +5463,6 @@ gfc_conv_subref_array_arg (gfc_se *se, gfc_expr * expr, int g77,
   tree tmp_index;
   tree tmp;
   tree base_type;
-  tree size;
   stmtblock_t body;
   int n;
   int dimen;
@@ -5706,42 +5705,8 @@ class_array_fcn:
   /* Determine the offset for pointer formal arguments and set the
      lbounds to one.  */
   if (formal_ptr)
-    {
-      size = gfc_index_one_node;
-      offset = gfc_index_zero_node;
-      for (n = 0; n < dimen; n++)
-	{
-	  tmp = gfc_conv_descriptor_ubound_get (parmse->expr,
-						gfc_rank_cst[n]);
-	  tmp = fold_build2_loc (input_location, PLUS_EXPR,
-				 gfc_array_index_type, tmp,
-				 gfc_index_one_node);
-	  gfc_conv_descriptor_ubound_set (&parmse->pre,
-					  parmse->expr,
-					  gfc_rank_cst[n],
-					  tmp);
-	  gfc_conv_descriptor_lbound_set (&parmse->pre,
-					  parmse->expr,
-					  gfc_rank_cst[n],
-					  gfc_index_one_node);
-	  size = gfc_evaluate_now (size, &parmse->pre);
-	  offset = fold_build2_loc (input_location, MINUS_EXPR,
-				    gfc_array_index_type,
-				    offset, size);
-	  offset = gfc_evaluate_now (offset, &parmse->pre);
-	  tmp = fold_build2_loc (input_location, MINUS_EXPR,
-				 gfc_array_index_type,
-				 rse.loop->to[n], rse.loop->from[n]);
-	  tmp = fold_build2_loc (input_location, PLUS_EXPR,
-				 gfc_array_index_type,
-				 tmp, gfc_index_one_node);
-	  size = fold_build2_loc (input_location, MULT_EXPR,
-				  gfc_array_index_type, size, tmp);
-	}
-
-      gfc_conv_descriptor_offset_set (&parmse->pre, parmse->expr,
-				      offset);
-    }
+    gfc_shift_descriptor (&parmse->pre, parmse->expr, dimen,
+			  rse.loop->from, rse.loop->to);
 
   /* We want either the address for the data or the address of the descriptor,
      depending on the mode of passing array arguments.  */