Request for review (S) 6780143: hs203t003 hits SIGSEGV/EXCEPTION_ACCESS_VIOLATION with -XX:+UseCompressedOops

[Coleen Phillimore]

It's not used later in the code so it didn't need to be saved.

Thanks!
Coleen

Vladimir Kozlov wrote:
> Coleen,
>
> Looks goor but could you explain why you removed saving RCX in 
> templateTable_x86_64.cpp?
>
> Thanks,
> Vladimir
>
> Coleen Phillimore wrote:
>>
>> Thanks to Tom for pointing out what was really killing r12, I have a 
>> new webrev with a better fix and better summary.
>>
>> Summary: Using r12 as temporary register around call_VM trashes 
>> heapbase because call_VM doesn't always return immediately to 
>> following code (eg forward_exception, popframe and early return 
>> support).
>>
>> open webrev at http://cr.openjdk.java.net/~coleenp/6780143/   (hit 
>> reload)
>> bug link at http://bugs.sun.com/view_bug.do?bug_id=6780143
>>
>> Thanks,
>> Coleen
>>
>> Tom Rodriguez wrote:
>>> The changes look ok but what code was killing r12?  All the existing 
>>> reinit_heapbase calls are because we're using the callee-saved-ness 
>>> of r12 to keep something else alive but that's no true here.
>>>
>>> tom
>>>
>>> On Nov 18, 2010, at 12:20 PM, coleen phillimore wrote:
>>>
>>>  
>>>> Summary: missing reinit_heapbase() when popframe support jumps back 
>>>> into interpreter from C code.
>>>>
>>>> open webrev at http://cr.openjdk.java.net/~coleenp/6780143/
>>>> bug link at http://bugs.sun.com/view_bug.do?bug_id=6780143
>>>>
>>>> Tested by running our jvmti tests including the failing test.
>>>>
>>>> Coleen
>>>>     
>>>
>>>