static void
predict_paths_for_bb (basic_block cur, basic_block bb,
enum br_predictor pred,
- enum prediction taken)
+ enum prediction taken,
+ bitmap visited)
{
edge e;
edge_iterator ei;
continue;
gcc_assert (bb == cur || dominated_by_p (CDI_POST_DOMINATORS, cur, bb));
- /* See if there is how many edge from e->src that is not abnormal
+ /* See if there is an edge from e->src that is not abnormal
and does not lead to BB. */
FOR_EACH_EDGE (e2, ei2, e->src->succs)
if (e2 != e
/* If there is non-abnormal path leaving e->src, predict edge
using predictor. Otherwise we need to look for paths
- leading to e->src. */
+ leading to e->src.
+
+ The second may lead to infinite loop in the case we are predicitng
+ regions that are only reachable by abnormal edges. We simply
+ prevent visiting given BB twice. */
if (found)
predict_edge_def (e, pred, taken);
- else
- predict_paths_for_bb (e->src, e->src, pred, taken);
+ else if (!bitmap_set_bit (visited, e->src->index))
+ predict_paths_for_bb (e->src, e->src, pred, taken, visited);
}
for (son = first_dom_son (CDI_POST_DOMINATORS, cur);
son;
son = next_dom_son (CDI_POST_DOMINATORS, son))
- predict_paths_for_bb (son, bb, pred, taken);
+ predict_paths_for_bb (son, bb, pred, taken, visited);
}
/* Sets branch probabilities according to PREDiction and
predict_paths_leading_to (basic_block bb, enum br_predictor pred,
enum prediction taken)
{
- predict_paths_for_bb (bb, bb, pred, taken);
+ bitmap visited = BITMAP_ALLOC (NULL);
+ predict_paths_for_bb (bb, bb, pred, taken, visited);
+ BITMAP_FREE (visited);
}
/* Like predict_paths_leading_to but take edge instead of basic block. */
break;
}
if (!has_nonloop_edge)
- predict_paths_for_bb (bb, bb, pred, taken);
+ {
+ bitmap visited = BITMAP_ALLOC (NULL);
+ predict_paths_for_bb (bb, bb, pred, taken, visited);
+ BITMAP_FREE (visited);
+ }
else
predict_edge_def (e, pred, taken);
}