RFR: 8325821: [REDO] use "dmb.ishst+dmb.ishld" for release barrier [v2]

[Aleksey Shipilev]

On Wed, 22 May 2024 11:11:59 GMT, kuaiwei <duke at openjdk.org> wrote:

>> test/hotspot/gtest/aarch64/test_assembler_aarch64.cpp line 198:
>> 
>>> 196: }
>>> 197: 
>>> 198: TEST_VM(AssemblerAArch64, merge_ldst) {
>> 
>> This test seems to be irrelevant for the issue at hand? Tests `ld/st` -> `ldp/stp` merging, not the barrier merges?
>
> In this patch, I fixed an issue, dmb/st/ld may not merge if CodeBuffer is expanding, I added some unit tests to check it.

Aha. So the logic is that the same issue that affects `dmb` merging also affects `ldp` merging? All right, it's fine to leave it here then.

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PR Review Comment: https://git.openjdk.org/jdk/pull/19278#discussion_r1622171573