x86 interpreters in hotspot

[Krystal Mok]

On Tue, May 8, 2012 at 10:54 AM, Xin Tong <xerox.time.tech at gmail.com> wrote:

> I think the trace_bytecode() is the function i want to extend. I want
> to get a list of all the executed and unique java bytecode PC.  i.e.
> if iconst_1 at bytecode index 1 in method foo() is executed many
> times, it will only count as one.
>
>
Are you trying to implement code coverage kind of stuff? If so,
trace_bytecode() is NOT what you want to touch. It's an overkill for your
purpose.

There are quite a few frameworks to do this, all based on instrumentation,
noteably EMMA, Cobertura and their derivatives. I'd suggest working on that
level.

If you insist on implementing such feature in the VM itself, I was
implementing a toy code coverage tool last night. If you could wait, I'll
post what I've got sometime later, perhaps next week.


> Also, what is an easy way to get the size of the interpreter code
> given a Java bytecode.
>

Could you give an example? I don't understand the question.

- Kris


>
> Xin
>
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