RFR (xs) 8075967: Zero interpreter asserts for SafeFetch<32, N> calls in ObjectMonitor

[Coleen Phillimore]

On 3/25/15, 2:29 PM, Severin Gehwolf wrote:
> Hi Coleen,
>
> Thanks for this!
>
> On Wed, 2015-03-25 at 13:53 -0400, Coleen Phillimore wrote:
>> Summary: Implement SafeFetchX unsafely and make CanUseSafeFetchX false
>> for Zero
>>
>> Also, this fixes a couple other minor issues.
>>
>> Ran jdk9 jck tests with one timeout.  hotspot/runtime jtreg tests don't
>> run because Zero doesn't support UseCompressedOops (not sure why) and
>> CDS (know why).
>>
>> open webrev at http://cr.openjdk.java.net/~coleenp/8075967/
>> bug link https://bugs.openjdk.java.net/browse/JDK-8075967
> Disclaimer: Not a reviewer.
>
> While I'd have preferred correct (safe) SafeFetchX implementations (or
> remove them for Zero) I don't see how we could do this for Zero in an
> arch-independent way. AFAIK, getting/setting the PC via ucontext is
> machine dependent and Zero may be running on any linux architecture
> where GCC is available.

Thanks for reviewing the code.  I suppose we should make implementing 
SafeFetch required for all platforms because it's called in platform 
independent code (or rewrite the platform independent code).   My goal 
at the moment was to see how well Zero works.  I don't know how well 
supported this variant is.  It seems to be missing a lot.

Thanks,
Coleen

>
> Changes look fine to me.
>
> Cheers,
> Severin
>
>> Thanks,
>> Coleen
>
>