[Bug tree-optimization/63168] loop header copying fails - not vectorized: latch block not empty

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63168

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Thu Oct 16 10:13:52 2014
New Revision: 216304

URL: https://gcc.gnu.org/viewcvs?rev=216304&root=gcc&view=rev
Log:
2014-10-16  Richard Biener  <rguenther@suse.de>

    PR tree-optimization/63168
    * tree-cfg.c (gimple_can_merge_blocks_p): Only protect
    latches if after merging they are no longer simple.
    * cfghooks.c (merge_blocks): Handle merging a latch block
    into another block.

    * gcc.dg/tree-ssa/loop-40.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/loop-40.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfghooks.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-cfg.c