[Bug middle-end/51212] ICE: verify_flow_info failed: BB 3 can not throw but has an EH edge with -fgnu-tm -fnon-call-exceptions and transaction_callable

["aldyh at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51212

Aldy Hernandez <aldyh at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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         AssignedTo|unassigned at gcc dot       |aldyh at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #2 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2011-12-21 16:28:12 UTC ---
The problem here is that with -fnon-call-exceptions, the load from *p may trap,
but when we instrument the store, we have lost the landing pad information.

We can save and attach the exception information to the instrumented load
(_ITM_RU*), but currently all the TM load/store builtins are marked as
no-throw.  Perhaps we can get rid of the no-throw bit when
-fnon-call-exceptions is enabled.

Maybe something like this:

1. Get rid of the NOTHROW bits from the TM load/store builtins.
2. Attach the EH information to the TM load/store calls.
3. Split the BB accordingly when the TM load/store calls are not the last in
the BB (because we have added a cast after the instrumentation).

How does this sound Richard?