[Bug rtl-optimization/48141] [4.4/4.5/4.6 Regression] DSE compile time hog

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48141

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-03-26 09:20:36 UTC ---
Author: jakub
Date: Sat Mar 26 09:20:34 2011
New Revision: 171546

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=171546
Log:
    Backport from mainline
    2011-03-17  Jakub Jelinek  <jakub@redhat.com>

    PR rtl-optimization/48141
    * params.def (PARAM_MAX_DSE_ACTIVE_LOCAL_STORES): New.
    * dse.c: Include params.h.
    (active_local_stores_len): New variable.
    (add_wild_read, dse_step1): Clear it when setting active_local_stores
    to NULL.
    (record_store, check_mem_read_rtx): Decrease it when removing
    from the chain.
    (scan_insn): Likewise.  Increase it when adding to chain, if it
    reaches PARAM_MAX_DSE_ACTIVE_LOCAL_STORES limit, set to 1 and
    set active_local_stores to NULL before the addition.
    * Makefile.in (dse.o): Depend on $(PARAMS_H).

Modified:
    branches/gcc-4_6-branch/gcc/ChangeLog
    branches/gcc-4_6-branch/gcc/Makefile.in
    branches/gcc-4_6-branch/gcc/dse.c
    branches/gcc-4_6-branch/gcc/params.def