RFR: 8355704: RISC-V: enable TestIRFma.java [v2]

[Robbin Ehn]

On Thu, 1 May 2025 08:36:29 GMT, Hamlin Li <mli at openjdk.org> wrote:

>> Hi,
>> Can you help to review this patch to enable TestIRFma.java?
>> FmaF/D (checked by TestIRFma.java) are supported on riscv, but for some reason we can not enable it easily, but we should enable it.
>> 
>> NOTE: the reason I change IRNode matching rules is that, previously it verify the `FINAL CODE` where every platform could have different instruct name; I change it from machOnlyNameRegex to beforeMatchingNameRegex, to make it verify the `PrintIdeal` where every platform share the same names.
>> 
>> Also tested on machine with `asimd` support.
>> 
>> Thanks!
>
> Hamlin Li has updated the pull request incrementally with one additional commit since the last revision:
> 
>   adjust IR verification

Thanks, looks good!

test/hotspot/jtreg/compiler/c2/irTests/TestIRFma.java line 91:

> 89:     @IR(counts = {IRNode.FMSUB, "> 0"},
> 90:         applyIfCPUFeature = {"asimd", "true"})
> 91:     @IR(counts = {IRNode.FMA_F, "= 1"},

When you read these tests, it is a bit hard to know how that IRNode.XX do the matching.
In this case FMSUB is actually not an IRNode but an instruction, which I didn't understand.

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Marked as reviewed by rehn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24947#pullrequestreview-2809392301
PR Review Comment: https://git.openjdk.org/jdk/pull/24947#discussion_r2070011735