RFR (XS) 8000753: compiler/6912517 crashes on 64bit sparc with compressed oops off

[Roland Westrelin]

> UseCompressedKlassPointers is constant 'false' in 32bit VM so ShouldNotReachHere() branch will not be executed and useless. How about this code:
> #ifdef _LP64
> if (offset -- … && UseCompressedKlassPointers) {
> …
>   } else
> #endif
>   {

Ok. Should I push it?

Roland.