[14] RFR (S): 8226411: C2: Avoid memory barriers around off-heap unsafe accesses

[John Rose]

On Nov 29, 2019, at 7:42 AM, Vladimir Ivanov <vladimir.x.ivanov at oracle.com> wrote:
> 
> http://cr.openjdk.java.net/~vlivanov/8226411/webrev.00/ <http://cr.openjdk.java.net/~vlivanov/8226411/webrev.00/>
> https://bugs.openjdk.java.net/browse/JDK-8226411 <https://bugs.openjdk.java.net/browse/JDK-8226411>

That looks good to me.

I wonder if there is a similar opportunity in LibraryCallKit::inline_unsafe_load_store
or inline_vector_mem_operation or inline_unsafe_copyMemory.  All of those
also form unsafe addresses, and at least some seem to mention NULL_PTR or IN_HEAP.
Is it worth an explanatory comment or a tracking bug?

— John