[Bug target/68634] [6 Regression] ICE in maybe_record_trace_start, at dwarf2cfi.c:2284 w/ -O2 -fmodulo-sched

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68634

--- Comment #4 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Author: segher
Date: Fri Jan  8 03:58:40 2016
New Revision: 232148

URL: https://gcc.gnu.org/viewcvs?rev=232148&root=gcc&view=rev
Log:
shrink-wrap: Once more PRs 67778, 68634, and now 68909

If a candidate PRE cannot get the prologue because a block BB is
reachable from it, but PRE does not dominate BB, we try again with the
dominators of PRE.  That "try again" needs to again consider BB though,
we aren't done with it.

        PR rtl-optimization/67778
        PR rtl-optimization/68634
        PR rtl-optimization/68909
        * shrink-wrap.c (try_shrink_wrapping): Add comment.  Don't pop
        block from the stack until done with it.  Remove a superfluous
        bitmap set.  Remove a superfluous bitmap test.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/shrink-wrap.c