RFR: 8350940: RISC-V: remove unnecessary assert_different_registers in minmax_fp [v2]

[Fei Yang]

On Fri, 28 Feb 2025 11:50:08 GMT, Hamlin Li <mli at openjdk.org> wrote:

>> Hi,
>> Can you help to review this simple change?
>> Seems to me it's not necessary to assert_different_registers between dst/src1/src2 in minmax_fp.
>> 
>> Thanks
>
> Hamlin Li has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains two commits:
> 
>  - merge master
>  - initial commit

src/hotspot/cpu/riscv/c2_MacroAssembler_riscv.cpp line 2140:

> 2138:   assert_different_registers(dst, src1);
> 2139:   assert_different_registers(dst, src2);
> 2140: 

Ah, Seems I missed this in my last PR :-)  Looks reasonable to me.
But we should remove the `TEMP_DEF dst` effect from the related match rule in riscv.ad file where it is called.
One example: https://github.com/openjdk/jdk/blob/master/src/hotspot/cpu/riscv/riscv.ad#L7290

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PR Review Comment: https://git.openjdk.org/jdk/pull/23842#discussion_r1975314192