Really?

I thought I remembered seeing J calls being implemented as C calls?

Thanks,

-- 
Raul

On Tue, May 14, 2019 at 1:42 PM Henry Rich <[email protected]> wrote:
>
> The J stack is separate from the C stack, and always has been.
>
> The trouble comes from the fact that the code is old and has been
> rewritten lots.  Debug sits off to the side and had pointers into the
> blocks used by normal verb execution.  This made it hard for the
> optimizer, and also for the programmer who looks at 'i' and wonders what
> it really means.  So in this release I structured the interaction
> between debug and normal execution.  As for getting it right... I guess
> that's what beta releases are for.  Thanks to you guys who find the bugs.
>
> Henry Rich
>
> On 5/14/2019 1:36 PM, Raul Miller wrote:
> > Nice.
> >
> > Since the current J implementation uses the C stack to implement the J
> > stack, cutting back requires one of two things:
> >
> > (1) Every C function which can take significant time to execute or
> > which can be live during an exception needs to implement "bail out
> > early" checks, or
> >
> > (2) setjump/longjump (which sometimes gets into hardware and operating
> > system specific issues, and also has implications for memory
> > management because of how references can get ignored -- that said, for
> > example, gdb uses a linked list that emulates the stack for memory
> > management purposes with "primitives" to add a frame, remove a frame
> > or cut back to the current frame -- I don't know what the performance
> > implications of that would be like, here).
> >
> > So... yes... I imagine it's more than a little intricate.
> >
> > So... thanks!
> >
>
>
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