* except.c (insn_eh_region, maximum_uid): New static variables.
(set_insn_eh_region): New static function to set region numbers.
(free_insn_eh_region): New function to free EH region table.
(init_insn_eh_region): New function to initialize EH region table.
(in_same_eh_region): New function used to determine if two rtl
instructions are in the same exception region or not.
From-SVN: r18624
