Re: [Libjit] Getting started on the project, looking to contribute, have some questions

[Aleksey Demakov]

On Thu, May 2, 2013 at 7:12 PM, Ben Vanik <address@hidden> wrote:

Awesome! Thank you!

If there's any cleanup work that I can help with, please let me know!

Actually there is no much to cleanup. The thing is that there were

several modifications started and never completed. So they need

to be completed rather than cleaned up.

In my TODO list the first thing is to complete the new code memory 

allocation mechanism. It should be based on the low-level functions 

provided by jit-vmem.c. The current mechanism is implemented in

jit-memory-cache.c. During code generation if there is no space left

it allocates a new memory block, abandons already generated code

and restarts the function code generations from the very begining.

The new memory allocator should just reserve very large address

space on the start up. The operating system virtual memory should

not take any physical pages at this moment. When during code 

generation there is no space it is needed just to map a few more

pages of the reserved space and continue without restarting.

This is how it is done in most modern VMs. E.g. Java VMs, v8,

luajit, etc. It is needed to do the same in libjit.

Regards,

Aleksey