Re: [Valgrind-users] Memcheck with Jikes RVM

[Karl C. <ka...@cs...>]

On 07/08/2014 02:48 PM, Philippe Waroquiers wrote:
> On Tue, 2014-07-08 at 14:39 -0400, Eliot Moss wrote:
>> On 7/8/2014 2:04 PM, Philippe Waroquiers wrote:
>>> On Tue, 2014-07-08 at 03:49 -0400, Karl Cronburg wrote:
>>
>> I can confirm that Jikes RVM does it own special allocation
>> of stacks, which might be involved here.
>>
>> I am wondering why anyone would think a tool like memcheck
>> would work with a Java virtual machine like JikesRVM, with
>> its own notion of object, garbage collection, etc.  For
>> example, JikesRVM almost certainly explicitly clears memory
>> before using it for objects, which would mean it is initialized,
>> and verified Java bytecode will never access an uninitialized
>> local variable.  I suppose you might get some mileage on
>> checking JNI / native code stuff, but I'm not sure.  So,
>> I am intrigued, but also wondering if maybe you're barking
>> up the wrong tree here ...
>>
>> Regards -- Eliot (Hi, Sam!)
> I guess memcheck could be useful for checking the RVM itself,
> not the Java code run by RVM.
> And maybe things like cachegrind/callgrind/helgrind might be useful ?
> 
> Note that I have since a long time on my list of things to never do
> to look at defining client requests allowing a JIT compiler to
> indicate to Valgrind how to unwind and so make a reasonable
> "source" stacktrace of the JIT-ed code.
> Might make Valgrind a lot more interesting for mixed JIT code and JNI
> and 'virtual machine implementation' follow up.
> 
> Philippe
> 
> 

We're interested in using malloc/free client requests to see if we can
get memcheck to tell us when the garbage collector is handling its'
own memory incorrectly.

-Karl-