RFR [11] 8207838: AArch64: Float registers incorrectly resture in JNI call

[Aleksey Shipilev]

On 08/14/2018 02:47 PM, Andrew Haley wrote:
> When we make a JNI call with several floating-point args they are
> pushed and then popped in the reverse order.  The fix it trivial and
> obvious and affects AArch64 only.
> 
> The patch also affects non-AArch64 targets only in that it adds a test
> for this case.
> 
> OK for 11?
> 
> https://bugs.openjdk.java.net/browse/JDK-8207838
> http://cr.openjdk.java.net/~fyang/8207838/webrev.00/

Whoops. The fix looks good for 11, but I am not the actual approver :)

In the test, why do we need to call the test in separate threads? AFAIU, throwing Error from those
threads would print them out to stderr, but it would not have other effects, e.g. changing the exit
code of the test itself, so failures may go unnoticed. Might be better to use ExecutorService, get
the Future<?>-s, and rethrow ExecutionExceptions.

-Aleksey