Re: [Valgrind-users] Memcheck with Jikes RVM

[Philippe W. <phi...@sk...>]

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