RFR: 8353665: RISC-V: IR verification fails in TestSubNodeFloatDoubleNegation.java [v2]

[Hamlin Li]

On Fri, 4 Apr 2025 13:25:13 GMT, Hamlin Li <mli at openjdk.org> wrote:

>> Hi,
>> Can you help to review this patch?
>> The newly added TestSubNodeFloatDoubleNegation.java (in https://github.com/openjdk/jdk/pull/24150) is to check `0 - (0 - x)` is not folded to `x` for float and double.
>> I have manually checked the IR and generated assembly code, it's not folded on riscv either, just there is an extra SubF in some code path.
>> So, the fix for this test on riscv should be simply make the check as `>= 2` rather than `2`.
>> 
>> Tested on both x86 and riscv64.
>> 
>> Thanks
>
> Hamlin Li has updated the pull request incrementally with one additional commit since the last revision:
> 
>   refine

Great!
Let's fix this test first, I'll just fix riscv part, as I don't have the env to verify other platforms.
Also file a bug to track this `SubF` (potential) "issue", https://bugs.openjdk.org/browse/JDK-8353732, feel free to take it when you want to start the work.

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PR Comment: https://git.openjdk.org/jdk/pull/24421#issuecomment-2778738383