* tree-eh.c (tree_remove_unreachable_handlers): Handle shared labels.
(tree_empty_eh_handler_p): Allow non-EH predecestors; allow region
to be reached by different label than left.
(update_eh_edges): Update comment; remove edge_to_remove if possible
and return true if suceeded.
(cleanup_empty_eh): Accept sharing map; handle shared regions.
(cleanup_eh): Compute sharing map.
* except.c (remove_eh_handler_and_replace): Add argument if we should
update regions.
(remove_unreachable_regions): Update for label sharing.
(label_to_region_map): Likewise.
(get_next_region_sharing_label): New function.
(remove_eh_handler_and_replace): Add update_catch_try parameter; update
prev_try pointers.
(remove_eh_handler): Update.
(remove_eh_region_and_replace_by_outer_of): New function.
* except.h (struct eh_region): Add next_region_sharing_label.
(remove_eh_region_and_replace_by_outer_of,
get_next_region_sharing_label): Declare.
* tree-cfgcleanup.c (tree_forwarder_block_p): Simplify.
* tree-cfg.c (split_critical_edges): Split also edges where we can't
insert code even if they are not critical.
* tree-cfg.c (gimple_can_merge_blocks_p): EH edges are unmergable.
(gimple_can_remove_branch_p): EH edges won't remove branch by
redirection.
* tree-inline.c (update_ssa_across_abnormal_edges): Do handle
updating of non-abnormal EH edges.
* tree-cfg.c (gimple_can_merge_blocks_p): EH edges are unmergable.
(gimple_can_remove_branch_p): EH edges are unremovable by redirection.
(split_critical_edges): Split also edges where emitting code on them
will lead to splitting later.
From-SVN: r146763
