[vectorIntrinsics] RFR: Optimize mem barriers for ByteBuffer cases [v8]

[Radoslaw Smogura]

On Wed, 4 Aug 2021 15:12:35 GMT, Paul Sandoz <psandoz at openjdk.org> wrote:

>> Radoslaw Smogura has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Minor stylistic fixes.
>
> src/java.base/share/classes/jdk/internal/misc/X-ScopedMemoryAccess.java.template line 421:
> 
>> 419:                       bb, offset, s,
>> 420:                       defaultImpl);
>> 421:             }
> 
> Can we try collapsing that to:
> Suggestion:
> 
>               return VectorSupport.load(vmClass, e, length,
>                       base, BufferAccess.bufferAddress(bb, offset),
>                       bb, offset, s,
>                       defaultImpl);
> 
> ? That appeared to be ok when i ran the benchmark for the non-polluted cases.

When I reverted changes I took base as `Object`, from `BufferAccess`, and did not work. Looks like cast to byte[] implies some kind of null checks, and we can use this.

-------------

PR: https://git.openjdk.java.net/panama-vector/pull/104