[Bug middle-end/39976] [4.5/4.6/4.7 Regression] Big sixtrack degradation on powerpc 32/64 after revision r146817

[wschmidt at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39976

--- Comment #42 from William J. Schmidt <wschmidt at gcc dot gnu.org> 
2011-12-08 22:00:52 UTC ---
Author: wschmidt
Date: Thu Dec  8 22:00:38 2011
New Revision: 182140

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=182140
Log:
2011-12-08  Bill Schmidt  <wschm...@linux.vnet.ibm.com>

    PR middle-end/39976
    * tree-ssa-dom.c (enum expr_kind): Add EXPR_PHI.
    (struct hashable_expr): Add struct phi field.
    (initialize_hash_element): Handle phis; change to use XCNEWVEC.
    (hashable_expr_equal_p): Handle phis.
    (iterative_hash_hashable_expr): Likewise.
    (print_expr_hash_elt): Likewise.
    (free_expr_hash_elt): Likewise.
    (dom_opt_enter_block): Create equivalences from redundant phis.
    (eliminate_redundant_computations): Handle redundant phis.
    (lookup_avail_expr): Handle phis.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/tree-ssa-dom.c