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[Fortran,1/2] Proposal on renaming gfc_vtable_*_get() to gfc_class_vtab_*_get()

Message ID 20150316152038.69867f6c@vepi2
State New
Headers show

Commit Message

Andre Vehreschild March 16, 2015, 2:20 p.m. UTC 
Hi all,

I like to propose a rename and split of the function
trans-expr.c::gfc_vtable_*_get(). 

Background: During fixing an issue, I encountered the case, that I had a handle
to get the vptr already and now wanted to retrieve the size component using that
vtpr handle. There was no function to easily do this. One is only able to get
the size member of a class' vtab using the function gfc_vtable_size_get(). I
therefore resided to extract from the gfc_vtable_field_get() function, which is
called by all gfc_vtable_*_get() functions, the part that is taking care about
the vptr's component ref and put it into a new function vptr_field_get(). The
old gfc_vtable_field_get () then calls this new vptr_field_get() function.

During the split it occurred to me, that the name for gfc_vtable_*_get() is not
clearly saying what it is supposed to do. When reading the function name the
first time, one may think, that the function gets the named field from a vtable,
but looking into the function one learns that not a handle to a vptr is
expected, but a handle to a class object. Therefore I propose to rename the
gfc_vtable_*_get () function to gfc_class_vtab_*_get (). 

Side note: Unfortunately we are not allowed to use ' in function names, or the
name would have been even better gfc_class'_vtab's_*_get (), e.g., for size
gfc_class'_vtab's_size_get (). 

This is a two parts patch. This first patch does the split and introduces
defines to stick with the old gfc_vtable_*_get (). 

The second part substitutes the new name gfc_class_vtab_*_get () where needed.

Bootstraps and regtests fine on x86_64-linux-gnu/F20.

Ok for trunk?

Regards,
	Andre
diff mbox

Patch

diff --git a/gcc/fortran/trans-expr.c b/gcc/fortran/trans-expr.c
index f61c79f..062c927 100644
--- a/gcc/fortran/trans-expr.c
+++ b/gcc/fortran/trans-expr.c
@@ -176,72 +176,85 @@  gfc_class_len_get (tree decl)
   if (POINTER_TYPE_P (TREE_TYPE (decl)))
     decl = build_fold_indirect_ref_loc (input_location, decl);
   len = gfc_advance_chain (TYPE_FIELDS (TREE_TYPE (decl)),
-			    CLASS_LEN_FIELD);
+			   CLASS_LEN_FIELD);
   return fold_build3_loc (input_location, COMPONENT_REF,
 			  TREE_TYPE (len), decl, len,
 			  NULL_TREE);
 }
 
 
+/* Get the specified FIELD from the VPTR.  */
+
 static tree
-gfc_vtable_field_get (tree decl, int field)
+vptr_field_get (tree vptr, int fieldno)
 {
-  tree size;
-  tree vptr;
-  vptr = gfc_class_vptr_get (decl);
+  tree field;
   vptr = build_fold_indirect_ref_loc (input_location, vptr);
-  size = gfc_advance_chain (TYPE_FIELDS (TREE_TYPE (vptr)),
-			    field);
-  size = fold_build3_loc (input_location, COMPONENT_REF,
-			  TREE_TYPE (size), vptr, size,
-			  NULL_TREE);
-  /* Always return size as an array index type.  */
-  if (field == VTABLE_SIZE_FIELD)
-    size = fold_convert (gfc_array_index_type, size);
-  gcc_assert (size);
-  return size;
+  field = gfc_advance_chain (TYPE_FIELDS (TREE_TYPE (vptr)),
+			     fieldno);
+  field = fold_build3_loc (input_location, COMPONENT_REF,
+			   TREE_TYPE (field), vptr, field,
+			   NULL_TREE);
+  gcc_assert (field);
+  return field;
 }
 
 
-tree
-gfc_vtable_hash_get (tree decl)
-{
-  return gfc_vtable_field_get (decl, VTABLE_HASH_FIELD);
-}
-
+/* Get the field from the class' vptr.  */
 
-tree
-gfc_vtable_size_get (tree decl)
+static tree
+class_vtab_field_get (tree decl, int fieldno)
 {
-  return gfc_vtable_field_get (decl, VTABLE_SIZE_FIELD);
+  tree vptr;
+  vptr = gfc_class_vptr_get (decl);
+  return vptr_field_get (vptr, fieldno);
 }
 
 
-tree
-gfc_vtable_extends_get (tree decl)
-{
-  return gfc_vtable_field_get (decl, VTABLE_EXTENDS_FIELD);
+/* Define a macro for creating the class_vtab_* and vptr_* accessors in
+   unison.  */
+#define VTAB_GET_FIELD_GEN(name, field) tree \
+gfc_class_vtab_## name ##_get (tree cl) \
+{ \
+  return class_vtab_field_get (cl, field); \
+} \
+ \
+tree \
+gfc_vptr_## name ##_get (tree vptr) \
+{ \
+  return vptr_field_get (vptr, field); \
 }
 
+VTAB_GET_FIELD_GEN (hash, VTABLE_HASH_FIELD)
+VTAB_GET_FIELD_GEN (extends, VTABLE_EXTENDS_FIELD)
+VTAB_GET_FIELD_GEN (def_init, VTABLE_DEF_INIT_FIELD)
+VTAB_GET_FIELD_GEN (copy, VTABLE_COPY_FIELD)
+VTAB_GET_FIELD_GEN (final, VTABLE_FINAL_FIELD)
 
-tree
-gfc_vtable_def_init_get (tree decl)
-{
-  return gfc_vtable_field_get (decl, VTABLE_DEF_INIT_FIELD);
-}
 
+/* The size field is returned as an array index.  Therefore treat it and only
+   it specially.  */
 
 tree
-gfc_vtable_copy_get (tree decl)
+gfc_class_vtab_size_get (tree cl)
 {
-  return gfc_vtable_field_get (decl, VTABLE_COPY_FIELD);
+  tree size;
+  size = class_vtab_field_get (cl, VTABLE_SIZE_FIELD);
+  /* Always return size as an array index type.  */
+  size = fold_convert (gfc_array_index_type, size);
+  gcc_assert (size);
+  return size;
 }
 
-
 tree
-gfc_vtable_final_get (tree decl)
+gfc_vptr_size_get (tree vptr)
 {
-  return gfc_vtable_field_get (decl, VTABLE_FINAL_FIELD);
+  tree size;
+  size = vptr_field_get (vptr, VTABLE_SIZE_FIELD);
+  /* Always return size as an array index type.  */
+  size = fold_convert (gfc_array_index_type, size);
+  gcc_assert (size);
+  return size;
 }
 
 
diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h
index 3ba2f88..4b9e8ac 100644
--- a/gcc/fortran/trans.h
+++ b/gcc/fortran/trans.h
@@ -346,17 +346,32 @@  typedef struct
 gfc_wrapped_block;
 
 /* Class API functions.  */
+tree gfc_class_set_static_fields (tree, tree, tree);
 tree gfc_class_data_get (tree);
 tree gfc_class_vptr_get (tree);
 tree gfc_class_len_get (tree);
+#define gfc_vtable_hash_get gfc_class_vtab_hash_get
+#define gfc_vtable_size_get gfc_class_vtab_size_get
+#define gfc_vtable_extends_get gfc_class_vtab_extends_get
+#define gfc_vtable_def_init_get gfc_class_vtab_def_init_get
+#define gfc_vtable_copy_get gfc_class_vtab_copy_get
+#define gfc_vtable_final_get gfc_class_vtab_final_get
+/* Get an accessor to the class' vtab's * field, when a class handle is
+   available.  */
+tree gfc_class_vtab_hash_get (tree);
+tree gfc_class_vtab_size_get (tree);
+tree gfc_class_vtab_extends_get (tree);
+tree gfc_class_vtab_def_init_get (tree);
+tree gfc_class_vtab_copy_get (tree);
+tree gfc_class_vtab_final_get (tree);
+/* Get an accessor to the vtab's * field, when a vptr handle is present.  */
+tree gfc_vtpr_hash_get (tree);
+tree gfc_vptr_size_get (tree);
+tree gfc_vptr_extends_get (tree);
+tree gfc_vptr_def_init_get (tree);
+tree gfc_vptr_copy_get (tree);
+tree gfc_vptr_final_get (tree);
 void gfc_reset_vptr (stmtblock_t *, gfc_expr *);
-tree gfc_class_set_static_fields (tree, tree, tree);
-tree gfc_vtable_hash_get (tree);
-tree gfc_vtable_size_get (tree);
-tree gfc_vtable_extends_get (tree);
-tree gfc_vtable_def_init_get (tree);
-tree gfc_vtable_copy_get (tree);
-tree gfc_vtable_final_get (tree);
 tree gfc_get_vptr_from_expr (tree);
 tree gfc_get_class_array_ref (tree, tree);
 tree gfc_copy_class_to_class (tree, tree, tree);