Re: lua_Debug in 5.4: add currentpc?

[Dibyendu Majumdar <mobile@...>]

Hi,

On 8 January 2018 at 20:22, Dan Tull <dtull@adobe.com> wrote:
> Yes. The version of Lua various projects at Adobe use has a patch
> to allow checking the current opcode and it has been super useful and
> is quite easy to do. It also has a 'basepc' which is essentially an ID for
> function in a chunk based on a depth first traversal of the proto hierarchy
> adding up all the opcodes.
>
> We use those for generating usable* tracebacks from builds with compiled
> Lua (no line number debug info) and sometimes with other tools as
> well (our sampling profiler** and code coverage mechanisms can
> operate on stripped code as well). It was also handy for a special
> high performance coverage mechanism that used self-clearing
> breakpoints*** to gather opcode resolution coverage (so it could see
> which branches are taken, not just line hits) with very low overhead.
>

Are your patches available somewhere such as github?

> That said, we've never bothered (for various reasons) with Lua
> versions past 5.1, so haven't bothered to push for any of those
> changes to be adopted into Lua itself.
>

I am interested to know what the reasons are for staying with 5.1,
would be great if you could share.

Thanks and Regards
Dibyendu