Digging a bit deeper into JIT's compile internals

[Joshua Saxby <joshua.a.saxby@gmail.com>]

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After following files jit-recording.cc and jit-playback.cc, I think I've
found out where I need to patch JIT to do what I want it to do.

Looks like both compiling to file and memory ultimately rely upon
playback::context::compile() to do the bulk of their work and then override
a postprocess() method to do additional handling pertaining to their
specific task.

If I can find a way to cache or store the intermediate result generated by
compile(), I should then be able to restructure this to have the follow-up
tasks required by both different forms of compilation to be done starting
with this intermediate result.

Anyone see a problem with my approach? I'm hoping it will be possible to
reüse compilation results produced by compile() in this way without it
causing any conflicts...

Regards,
*J.S.*



*My PGP Public Key Identity*

pub   4096R/*B7A947E4* 2016-11-16 [expires: 2025-12-31]
      Key fingerprint = *E2C4 514F F0FA 52D1 896A  B1D6 3D42 BFD9 B7A9 47E4*
uid       Joshua Saxby <joshua.a.saxby+UMvLnvbsOxBHaeiCHvbdunpz@gmail.com>
uid                   Joshua Saxby (saxbophone) <joshua.a.saxby@gmail.com>
sub   4096R/0A445946 2016-11-16 [expires: 2025-12-31]




On Sat, 10 Jun 2023 at 13:00, <jit-request@gcc.gnu.org> wrote:

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> Today's Topics:
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>    1. Modifying the jit compiler API? (Joshua Saxby)
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> ---------- Forwarded message ----------
> From: Joshua Saxby <joshua.a.saxby@gmail.com>
> To: jit@gcc.gnu.org
> Cc:
> Bcc:
> Date: Sat, 10 Jun 2023 00:04:43 +0100
> Subject: Modifying the jit compiler API?
> Currently the JIT has two functions allowing you to compile a context
> either to memory or to file.
>
> But what if you want to compile to both? There doesn't seem to be any way
> to do this except by calling both functions separately which I believe will
> effectively be two separate compilations...
>
> Presumably, it should be possible to modify this part of the API to compile
> to some form of intermediate representation of the work that is common to
> both kinds of compilation, and then turn that into code in memory and in
> file, respectively.
>
> Anyone got any pointers for me on where in the code would be the best place
> for me to modify to dupport this? I did take a look in the implementation
> code of JIT sone weeks ago and remember seeing lots of complicated stuff
> regarding recordings and replays that looked relevant...
>
> A slighty simpler alteration I am also interested in making is allowing
> compile to file to compile to a buffer in memory as well as a file (I
> suppose it could be termed "compile to binary"). Maybe I should start with
> that...
>
>