[Bug tree-optimization/55018] [4.6/4.7/4.8 Regression] CDDCE pass is too aggressive sometimes with infinite loops and with some functions

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55018

--- Comment #10 from Steven Bosscher <steven at gcc dot gnu.org> 2012-10-31 21:37:22 UTC ---
Author: steven
Date: Wed Oct 31 21:37:10 2012
New Revision: 193047

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=193047
Log:
gcc/
    PR tree-optimization/55018
    * basic-block.h (dfs_find_deadend): New prototype.
    * cfganal.c (dfs_find_deadend): No longer static.  Use bitmap
    instead of sbitmap for visited.
    (flow_dfs_compute_reverse_execute): Use dfs_find_deadend here, too.
    * dominance.c (calc_dfs_tree): If saw_unconnected,
    traverse from dfs_find_deadend of unconnected b
    instead of b directly.

testsuite/
    PR tree-optimization/55018
    * gcc.dg/torture/pr55018.c: New test.


Added:
    trunk/gcc/testsuite/gcc.dg/torture/pr55018.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/basic-block.h
    trunk/gcc/cfganal.c
    trunk/gcc/dominance.c
    trunk/gcc/testsuite/ChangeLog