rfa: remove get_var_ann (was: Fix PR50260)

[Michael Matz <matz at suse dot de>]

Hi,

On Fri, 2 Sep 2011, Michael Matz wrote:

> > > Ok.  Time to make get_var_ann private?
> 
> As I feared the call to get_var_ann in set_is_used right now really is 
> still needed, privatizing it hence isn't that straight forward.

After pondering I concluded that it's not necessary to call set_is_used 
for variables without var annotation.  Those won't be in referenced_vars 
(or local_decls) and therefore also won't be removed from those lists no 
matter how hard we try.

Regstrapped on x86_64-linux (without Ada).  Okay for trunk?


Ciao,
Michael.
-- 
	* tree-flow.h (get_var_ann): Don't declare.
	* tree-flow-inline.h (get_var_ann): Remove.
	(set_is_used): Use var_ann, not get_var_ann.
	* tree-dfa.c (add_referenced_var): Inline body of get_var_ann.
	* tree-ssa-live.c (mark_all_vars_used_1): Check var_ann before
	calling set_is_used.

Index: tree-flow-inline.h
===================================================================
--- tree-flow-inline.h	(Revision 178488)
+++ tree-flow-inline.h	(Arbeitskopie)
@@ -145,16 +145,6 @@ var_ann (const_tree t)
   return p ? *p : NULL;
 }
 
-/* Return the variable annotation for T, which must be a _DECL node.
-   Create the variable annotation if it doesn't exist.  */
-static inline var_ann_t
-get_var_ann (tree var)
-{
-  var_ann_t *p = DECL_VAR_ANN_PTR (var);
-  gcc_checking_assert (p);
-  return *p ? *p : create_var_ann (var);
-}
-
 /* Get the number of the next statement uid to be allocated.  */
 static inline unsigned int
 gimple_stmt_max_uid (struct function *fn)
@@ -568,7 +558,7 @@ phi_arg_index_from_use (use_operand_p us
 static inline void
 set_is_used (tree var)
 {
-  var_ann_t ann = get_var_ann (var);
+  var_ann_t ann = var_ann (var);
   ann->used = true;
 }
 
Index: tree-flow.h
===================================================================
--- tree-flow.h	(Revision 178488)
+++ tree-flow.h	(Arbeitskopie)
@@ -278,7 +278,6 @@ typedef struct immediate_use_iterator_d
 typedef struct var_ann_d *var_ann_t;
 
 static inline var_ann_t var_ann (const_tree);
-static inline var_ann_t get_var_ann (tree);
 static inline void update_stmt (gimple);
 static inline int get_lineno (const_gimple);
 
Index: tree-dfa.c
===================================================================
--- tree-dfa.c	(Revision 178488)
+++ tree-dfa.c	(Arbeitskopie)
@@ -580,8 +580,9 @@ set_default_def (tree var, tree def)
 bool
 add_referenced_var (tree var)
 {
-  get_var_ann (var);
   gcc_assert (DECL_P (var));
+  if (!*DECL_VAR_ANN_PTR (var))
+    create_var_ann (var);
 
   /* Insert VAR into the referenced_vars hash table if it isn't present.  */
   if (referenced_var_check_and_insert (var))
Index: tree-ssa-live.c
===================================================================
--- tree-ssa-live.c	(Revision 178408)
+++ tree-ssa-live.c	(Arbeitskopie)
@@ -376,7 +376,10 @@ mark_all_vars_used_1 (tree *tp, int *wal
     {
       if (data != NULL && bitmap_clear_bit ((bitmap) data, DECL_UID (t)))
 	mark_all_vars_used (&DECL_INITIAL (t), data);
-      set_is_used (t);
+      /* If something has no annotation it's neither in referenced_vars,
+         nor in local_decls.  No use in marking it as used.  */
+      if (var_ann (t))
+	set_is_used (t);
     }
   /* remove_unused_scope_block_p requires information about labels
      which are not DECL_IGNORED_P to tell if they might be used in the IL.  */