State of openjdk on hppa

[Andrew Haley]

On 01/06/2010 04:47 PM, Tom Rodriguez wrote:
>> I'm not 100% sure what the correct value of this would be for HPPA.
>> The ABI stack grows upwards, but the stack Zero maintains still grows
>> downwards.  If interpreter_frame_expression_stack_direction is used
>> for both of these stacks then something will need changing (either a
>> separate accessor, or Zero's stack direction changing to match the
>> ABI stack.)
> 
> I don't really think hotspot cares which direction the ABI stack
> grows.  It only cares what direction the expression stack grows and
> that's only for frame code that it was walking over the contents of
> the expression stack..  I was assuming that the expression stack
> would follow the ABI but I guess there's no reason it must.  It's
> just the responsibility of the C++ intepreter to deal with that
> properly.  It would be nice to know what exact problem led to the
> initial conclusion that direction of stack growth was the problem.

Did you not see my reply?  The runtime write protects the guard pages
of the stack, and this immediately causes a segfault since the stack
being used is now unwritable,

Andrew.