[jdk17u-dev] RFR: 8330094: RISC-V: Save and restore FRM in the call stub

[Gui Cao]

On Wed, 1 May 2024 02:17:59 GMT, Fei Yang <fyang at openjdk.org> wrote:

>> Hi, The same issue also exists in JDK17u. So I would like to backport [JDK-8330094](https://bugs.openjdk.org/browse/JDK-8330094) to jdk17u-dev. With this change, we save and restore the default floating-point control state when we enter and leave Java code, ensuring that we are still Java compatible if we're called via the JNI invocation interface with a weird FP control state. RISC-V specific change, risk is low.
>> The backport is not clean because jdk17u-dev only has partial vector api instruct, this backport-related instruct does not exist in jdk17u-dev.
>> 
>> ### Testing
>> 
>> - [x]  Run tier1-3 tests on SOPHON SG2042 (release)
>
> LGTM.

@RealFYang  : Thanks for the review.

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PR Comment: https://git.openjdk.org/jdk17u-dev/pull/2442#issuecomment-2094062761