On Sun, Nov 06, 2011 at 06:14:18PM +0100, Eric Botcazou wrote:
> > As has been suggested by Alexandre in the PR, this patch allows merging
> > basic blocks which couldn't be merged before because of user (non-forced)
> > labels at the beginning of the second basic blocks.
> > With this patch the user label is thrown away (for -g0 or -g
> > -fno-var-tracking-assignments) or turned into a debug bind stmt which
> > contains the label.
>
> Do we really want to do that if !optimize?
You're right, at -O0 we don't do VTA and thus the user labels would be
dropped on the floor.
Fixed thusly, committed to trunk as obvious:
2011-11-06 Jakub Jelinek <ja...@redhat.com>
* tree-cfg.c (gimple_can_merge_blocks_p): For -O0 don't remove
any user labels.
--- gcc/tree-cfg.c.jj 2011-11-04 18:01:25.000000000 +0100
+++ gcc/tree-cfg.c 2011-11-06 20:37:09.000000000 +0100
@@ -1454,8 +1454,8 @@ gimple_can_merge_blocks_p (basic_block a
break;
lab = gimple_label_label (stmt);
- /* Do not remove user forced labels. */
- if (!DECL_ARTIFICIAL (lab) && FORCED_LABEL (lab))
+ /* Do not remove user forced labels or for -O0 any user labels. */
+ if (!DECL_ARTIFICIAL (lab) && (!optimize || FORCED_LABEL (lab)))
return false;
}
Jakub
