[Bug tree-optimization/54489] tree FRE uses an excessive amount of memory

["rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54489

--- Comment #3 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-09-12 14:46:35 UTC ---
Author: rguenth
Date: Wed Sep 12 14:46:22 2012
New Revision: 191225

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=191225
Log:
2012-09-12  Richard Guenther  <rguenther@suse.de>

    PR tree-optimization/54489
    * tree-ssa-pre.c: Include domwalk.h.
    (in_fre): Remove.
    (sccvn_valnum_from_value_id): New function.
    (debug_bitmap_sets_for): Simplify.
    (get_representative_for): Properly initialize the SCCVN valnum.
    (create_expression_by_pieces): Likewise.
    (insert_into_preds_of_block): Likewise.
    (can_PRE_operation): Remove.
    (make_values_for_phi): Simplify.
    (compute_avail): Likewise.
    (do_SCCVN_insertion): Remove.
    (eliminate_avail, eliminate_push_avail, eliminate_insert):
    New functions.
    (eliminate): Split and perform a domwalk.
    (eliminate_bb): Former eliminate part that is now dom-enter.
    (eliminate_leave_block): New function.
    (fini_eliminate): Likewise.
    (init_pre): Simplify.
    (fini_pre): Likewise.
    (execute_pre): Fold into do_pre and do_fre.
    (do_pre): Consume execute_pre.
    (do_fre): Likewise.
    * Makefile.in (tree-ssa-pre.o): Add domwalk.h dependency.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/Makefile.in
    trunk/gcc/tree-ssa-pre.c