[Bug tree-optimization/59715] [4.7/4.8/4.9 Regression] wrong code at -Os and above on x86_64-linux-gnu

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59715

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 31774
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=31774&action=edit
untested patch

Like with the attached patch which performs edge-insertion.  But it doesn't
work that way because incrementally sinking then isn't able to figure out
a destination gsi (we can't do gsi_for_stmt on an edge-insertion-queued stmt,
bah).

But otherwise it fixes the bug ...

Leaves to disable the sinking, it's not the optimal insertion place anyway
(if not inserting on the edge).  Or to re-run critical edge splitting.