[Bug middle-end/38474] slow compilation at -O0 due to expand's temp slot goo

[matz at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38474

--- Comment #58 from Michael Matz <matz at gcc dot gnu.org> 2012-06-15 14:56:33 
UTC ---
Author: matz
Date: Fri Jun 15 14:56:26 2012
New Revision: 188667

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=188667
Log:
    PR middle-end/38474
    * cfgexpand.c (add_alias_set_conflicts): Remove.
    (expand_used_vars): Don't call it.
    (aggregate_contains_union_type): Remove.
    * function.c (n_temp_slots_in_use): New static data.
    (make_slot_available, assign_stack_temp_for_type): Update it.
    (init_temp_slots): Zero it.
    (remove_unused_temp_slot_addresses): Use it for quicker removal.
    (remove_unused_temp_slot_addresses_1): Use htab_clear_slot.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgexpand.c
    trunk/gcc/function.c