[Bug rtl-optimization/58679] [4.9 regression] ICE in create_pre_exit, at mode-switching.c:421 with -mavx after r202915

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58679

--- Comment #3 from Uroš Bizjak <ubizjak at gmail dot com> ---
For reference, the discussion of the change that removed REG_DEAD and
REG_UNUSED notes, started at [1].

[1] http://gcc.gnu.org/ml/gcc-patches/2013-09/msg01781.html