The Tree LIM pass keeps track of the execution status of statements by means of
/* The outermost loop for that execution of the header guarantees that the
block will be executed. */
#define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux)
and there is a fill_always_executed_in function:
/* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e.
for each such basic block bb records the outermost loop for that execution
of its header implies execution of bb. CONTAINS_CALL is the bitmap of
blocks that contain a nonpure call. */
It turns out that the function never references ALWAYS_EXECUTED_IN, which is a
little confusing. Instead it accesses the AUX field directly.
Changed to using ALWAYS_EXECUTED_IN in all cases. Tested on i586-suse-linux,
applied on the mainline as obvious.
2011-05-14 Eric Botcazou <ebotca...@adacore.com>
* tree-ssa-loop-im.c (SET_ALWAYS_EXECUTED_IN): New macro.
(fill_always_executed_in): Use [SET_]ALWAYS_EXECUTED_IN.
(tree_ssa_lim_finalize): Likewise.
--
Eric Botcazou
Index: tree-ssa-loop-im.c
===================================================================
--- tree-ssa-loop-im.c (revision 173756)
+++ tree-ssa-loop-im.c (working copy)
@@ -197,9 +197,10 @@ static bool ref_indep_loop_p (struct loo
/* Minimum cost of an expensive expression. */
#define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE))
-/* The outermost loop for that execution of the header guarantees that the
+/* The outermost loop for which execution of the header guarantees that the
block will be executed. */
#define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux)
+#define SET_ALWAYS_EXECUTED_IN(BB, VAL) ((BB)->aux = (void *) (VAL))
static struct lim_aux_data *
init_lim_data (gimple stmt)
@@ -2440,7 +2441,7 @@ fill_always_executed_in (struct loop *lo
edge e;
struct loop *inn_loop = loop;
- if (!loop->header->aux)
+ if (ALWAYS_EXECUTED_IN (loop->header) == NULL)
{
bbs = get_loop_body_in_dom_order (loop);
@@ -2482,7 +2483,7 @@ fill_always_executed_in (struct loop *lo
while (1)
{
- last->aux = loop;
+ SET_ALWAYS_EXECUTED_IN (last, loop);
if (last == loop->header)
break;
last = get_immediate_dominator (CDI_DOMINATORS, last);
@@ -2537,9 +2538,7 @@ tree_ssa_lim_finalize (void)
htab_t h;
FOR_EACH_BB (bb)
- {
- bb->aux = NULL;
- }
+ SET_ALWAYS_EXECUTED_IN (bb, NULL);
pointer_map_destroy (lim_aux_data_map);
