[Bug rtl-optimization/79125] [7 Regression] ICE in rtl_verify_bb_insns, at cfgrtl.c:2661 (error: flow control insn inside a basic block)

[law at redhat dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79125

Jeffrey A. Law <law at redhat dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2017-01-19
                 CC|                            |law at redhat dot com
     Ever confirmed|0                           |1

--- Comment #2 from Jeffrey A. Law <law at redhat dot com> ---
So in this case the conditional trap is in BB2 and is turned into an
unconditional trap by local cprop.  Note the code that currently scans for
traps skips BB2 (no global cprop can happen in that block).  It also ignores
insns that are unconditional traps at the start of the global pass.

local_cprop_pass ought to be able to see every possible conditional during its
scan.  Put those onto a worklist.

After the global pass is done, walk the worklist.  If the entry on the list is
an unconditional trap and its containing block has any successors, then we need
to split after the trap and insert the barrier.

It means a bit more worklist scanning, since we'll put all traps (conditional
or unconditional) on the list.  But that ought to be in the noise relative to
everything else going on.

Bernd, you want to take this one?  I've got a ppc64 beaker box handy for
additional testing once you've got a patch.