RFR: 8073093: AARCH64: C2 generates poor code for ByteBuffer accesses

[Alan Bateman]

On 13/02/2015 13:38, Andrew Haley wrote:
> java.​nio.​DirectByteBuffer.getXXX is slow for types larger than byte
> because the runtime does not know that AArch64 can perform unaligned
> memory accesses.
>
> The problem is due to this code in java.nio.Bits.unaligned():
>
>          unaligned = arch.equals("i386") || arch.equals("x86")
>              || arch.equals("amd64") || arch.equals("x86_64");
>
> If we add AArch64 to this list code quality is very much improved.
>
> http://cr.openjdk.java.net/~aph/8073093/
>
Make sense, I assume this will go in when JEP 237 is pushed.

-Alan