RFR: 8255719: Zero: on return path, check for pending exception before attempting to clear it

[Aleksey Shipilev]

On Tue, 3 Nov 2020 10:47:24 GMT, Severin Gehwolf <sgehwolf at openjdk.org> wrote:

>> Profiling shows we spend a lot of time trying to clear the pending exception at _return path, whereas it seldom is pending. 
>> 
>> The additional problem with calling into `clear_pending_exception` is that inlining budget is depleted completely at that point in the compilation unit, and so we do the full outbound call.
>> 
>> There are other places where we clear pending exception unconditionally, but those places do seem to expect the exceptions to be there.
>
> Seems reasonable.

Thanks @jerboaa!

-------------

PR: https://git.openjdk.java.net/jdk/pull/986