[Bug tree-optimization/55079] [4.8 regression] false positive -Warray-bounds

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55079

--- Comment #4 from Jan Hubicka <hubicka at gcc dot gnu.org> 2012-11-02 16:35:01 UTC ---
Author: hubicka
Date: Fri Nov  2 16:34:52 2012
New Revision: 193098

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=193098
Log:

    PR middle-end/55079
    * tree-ssa-loop-niter.c (number_of_iterations_exit): Update
    MAX field if NITER was folded to contant.
    (record_estimate): Sanity check.
    * tree-ssa-loop-ivcanon.c (remove_exits_and_undefined_stmts): New
    function.
    (remove_redundant_iv_test): New function.
    (loops_to_unloop, loops_to_unloop_nunroll): New static vars.
    (unloop_loops): Break out from ...
    (try_unroll_loop_completely): ... here; Pass in MAXITER; use
    remove_exits_and_undefined_stmts; do not unloop.
    (canonicalize_loop_induction_variables): Compute MAXITER;
    use remove_redundant_iv_test; remove loop_close_ssa_invalidated
    and irred_invalidated arguments.
    (canonicalize_induction_variables): Compute fresh bound estimates;
    unloop; walk from innermost.
    (tree_unroll_loops_completely): Likewise.

    * gcc.dg/tree-ssa/cunroll-10.c: New testcase.
    * gcc.dg/tree-ssa/cunroll-9.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/cunroll-10.c
    trunk/gcc/testsuite/gcc.dg/tree-ssa/cunroll-9.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-ssa-loop-ivcanon.c
    trunk/gcc/tree-ssa-loop-niter.c