Re: guile-vm 0.3

[Marius Vollmer]

Evan Prodromou <address@hidden> writes:

> >>>>> "MV" == Marius Vollmer <address@hidden> writes:
> 
>     MV> Please check out the guile-lightning module from CVS.  It
>     MV> contains the start for Lightning support in Guile.  You can
>     MV> play arround with the JIT assembler, but a lot details are
>     MV> missing to really integrate it into the Guile run-time.
> 
> Yeah! That's for sure. guile-lightning seems totally bizarre to me,
> actually. A user-level JIT? What's it for?

Well, you somehow need to write the JIT instructions, and I'm not
going to do that from C! ;)

I think this

    ((prolog 0)
     (mov ret (scm 0))
     (ret))

is much better than

    jit_prolog (0);
    jit_movr_l (JIT_RET, SCM_MAKINUM (0));
    jit_ret ();

I make so much mistakes when coding JIT in C (because I don't have
memorized all the details) that the Scheme layer catches for me.  For
example, I constantly write "jit_ldxr_l (JIT_R0, JIT_R0, offset)" when
I really mean "jit_ldxi_l".  In Scheme its just "(ldx r0 r0 offset)"
and the details are filled in automatically.