[10] RFR(XS) 8185736: missing default exception handler in calls to rethrow_Stub

[Vladimir Kozlov]

On 8/8/17 1:47 PM, Tom Rodriguez wrote:
> http://cr.openjdk.java.net/~never/8185736/webrev
> https://bugs.openjdk.java.net/browse/JDK-8185736

Looks good.

> 
> C2 exception handler tables must always contain a handler for the bci -1 
> since exceptions thrown during exception dispatch will attempt to 
> redispatch the recursive exception at bci -1.  C2's rethrow stub may end 
> up without a throw to the exit so one must be explicitly inserted to 
> ensure the VM doesn't abort during dispatch.  This happened reliably 
> because of a StackOverflowException in a Graal system running R code but 
> I was unable to build a test case for it.  You can see this missing 
> catch_pco by inspecting the -XX:+PrintExceptionHandlers output, so the 
> assert by itself show any place where C2 is exposed to this problem.  I 
> believe C1 builds it's exception handler tables differently and doesn't 
> necessarily include a -1 handler since it always contains an unwind 
> handler entry point which is used when no other handler is specified.
> 
> Vladimir ran I believe ran this through RBT.

Yes, it passed compiler's RBT.

Vladimir

> 
> tom