------- Additional Comments From rth at gcc dot gnu dot org 2005-02-03 02:59 ------- (In reply to comment #13) > [3] We could prohibit the simplification that extracts a symbol ref out of a > jump table, so that an indexed load is always performed a run-time, and so > changing the jump table is always safe.
I vote for this alternative. Nr 1 you'll have a hard time reliably detecting, nr 2 requires too many changes to too many backends (not that we don't need a new rtl multi-way branch representation, but we can't have it Now). I'm not sure I believe in nr 4 or nr 6. Nr 5 would work, but you probably forgot to put the label on the forced_labels list. Nr 7 is just gross. My guess is that we should get the bulk of the optimization that we were looking for from reading from the jump table from tree-level switch statement optimizations. And if not... tough. -- What |Removed |Added ---------------------------------------------------------------------------- Last reconfirmed|2004-11-23 16:10:55 |2005-02-03 02:59:53 date| | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18628