RFR: 8193266: AArch64: TestOptionsWithRanges.java SIGSEGV

[Stuart Monteith]

Hello,
   The Aarch64 backend decompresses klass pointers using XOR if the
size of the compressed classes space is less then the base address.
However, in JDK 10  CompressedClassSpaceSize doesn't represent the
range of the compressed shared classes area, which is set to 4GB.

   https://bugs.openjdk.java.net/browse/JDK-8193266
   http://cr.openjdk.java.net/~smonteith/8193266/webrev/

I've speculatively put up a patch which deals with the issue on
Aarch64. While I understand the problem with the generated aarch64
code, I don't believe understand the CDS code sufficiently at this
point to determine if there is a bug within the CDS code regarding the
CompressedClassSpaceSize parameter.

Thanks,
    Stuart