------- Comment #3 from abel at gcc dot gnu dot org 2009-12-28 12:06 -------
The patch mentioned by Alexander is not enough to fix the bug after applying
all other patches for sel-sched bugs. The actual problem is that when
redirecting an edge, the topological order of blocks in the currently
scheduling region may be broken. I had a patch to fix this, but didn't apply
it to trunk so got beaten by it. We will post it shortly.
* sel-sched-ir.c (sel_redirect_edge_and_branch): Recompute
topological order after redirecting an edge if needed.
diff --git a/gcc/sel-sched-ir.c b/gcc/sel-sched-ir.c
index 645093a..2baa461 100644
--- a/gcc/sel-sched-ir.c
+++ b/gcc/sel-sched-ir.c
@@ -5394,6 +5394,27 @@ sel_redirect_edge_and_branch (edge e, basic_block to)
gcc_assert (loop_latch_edge (current_loop_nest));
}
+ /* In rare situations, the topological relation between the blocks connected
+ by the redirected edge can change. Update block_to_bb/bb_to_block. */
+ if (CONTAINING_RGN (e->src->index) == CONTAINING_RGN (to->index)
+ && BLOCK_TO_BB (e->src->index) > BLOCK_TO_BB (to->index))
+ {
+ int i, n, rgn;
+ int *postorder, n_blocks;
+
+ postorder = XALLOCAVEC (int, n_basic_blocks);
+ n_blocks = post_order_compute (postorder, false, false);
+
+ rgn = CONTAINING_RGN (e->src->index);
+ for (n = 0, i = n_blocks - 1; i >= 0; i--)
+ if (CONTAINING_RGN (postorder[i]) == rgn)
+ {
+ BLOCK_TO_BB (postorder[i]) = n;
+ BB_TO_BLOCK (n) = postorder[i];
+ n++;
+ }
+ }
+
jump = find_new_jump (src, NULL, prev_max_uid);
if (jump)
sel_init_new_insn (jump, INSN_INIT_TODO_LUID | INSN_INIT_TODO_SIMPLEJUMP);
--
abel at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |abel at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42245
