RFR: 8351949: RISC-V: Cleanup and enable store-load peephole for membars [v4]

[Robbin Ehn]

On Tue, 18 Mar 2025 10:10:38 GMT, Fei Yang <fyang at openjdk.org> wrote:

>> No other platform uses '@' in their ad files?
>> E.g.
>> 
>>   format %{ "membar_acquire\n\t"
>>                      "dmb ishld" %}
>> 
>> 
>> It just looked weird that riscv have it's special way to format things.
>> 
>> I can agree with '#', but why add a @ ?
>
>> I can agree with '#', but why add a @ ?
> 
> I can't recall the history. Maybe just to mark that this is the start of a specific match rule thus making the opto asm more readable (and easier for the reader to map which instructions to which match rule). Opto output of some of the match rules are kind of complex like the compare ones (`CmpF3` etc.). But a single `#` also works for me.

Ok, reverted to original style for now.

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PR Review Comment: https://git.openjdk.org/jdk/pull/24035#discussion_r2002561056