RFR: JDK-8320892: AArch64: Restore FPU control state after JNI [v3]

[Andrew Haley]

On Wed, 29 Nov 2023 14:26:30 GMT, Andreas Woess <aw at openjdk.org> wrote:

>> Andrew Haley has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Fix thinko
>
> src/hotspot/cpu/aarch64/macroAssembler_aarch64.cpp line 4441:
> 
>> 4439:     bfi(tmp1, zr, 8, 5);  // Clear exception-control bits (8-12)
>> 4440:     eor(tmp2, tmp1, tmp2);
>> 4441:     cbz(tmp2, OK);        // Only reset FPCR if it's wrong
> 
> should we maybe do the same in [generate_call_stub](https://github.com/openjdk/jdk/pull/16637/files#diff-9112056f732229b18fec48fb0b20a3fe824de49d0abd41fbdb4202cfe70ad114R266), too (likely faster)?

Sure, it would be. I didn't think it was worthwhile, but we have the code now.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/16851#discussion_r1409398354