http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56131
--- Comment #5 from vries at gcc dot gnu.org 2013-01-29 19:34:08 UTC ---
A more structured version of the patch:
...
Index: cfgrtl.c
===================================================================
--- cfgrtl.c (revision 195240)
+++ cfgrtl.c (working copy)
@@ -135,7 +135,7 @@ delete_insn (rtx insn)
if (! can_delete_label_p (insn))
{
const char *name = LABEL_NAME (insn);
- basic_block bb = BLOCK_FOR_INSN (insn);
+ basic_block bb = NULL, label_bb = BLOCK_FOR_INSN (insn);
rtx bb_note = NEXT_INSN (insn);
really_delete = false;
@@ -143,8 +143,17 @@ delete_insn (rtx insn)
NOTE_KIND (insn) = NOTE_INSN_DELETED_LABEL;
NOTE_DELETED_LABEL_NAME (insn) = name;
- if (bb_note != NULL_RTX && NOTE_INSN_BASIC_BLOCK_P (bb_note)
- && BLOCK_FOR_INSN (bb_note) == bb)
+ if (bb_note != NULL_RTX
+ && NOTE_INSN_BASIC_BLOCK_P (bb_note))
+ bb = NOTE_BASIC_BLOCK (bb_note);
+
+ /* If the note following the label starts a basic block, and the
+ label is a member of the same basic block, interchange the two.
+ If the label is not marked with a bb, assume it's the same bb. */
+ */
+ if (bb != NULL
+ && (bb == label_bb
+ || label_bb == NULL))
{
reorder_insns_nobb (insn, insn, bb_note);
BB_HEAD (bb) = bb_note;
...
I'll try to bootstrap this patch on x86_64 coming weekend when I'll be back
home. I've also asked for access to the gcc compile farm to be able to test
this on a sparc machine.
