Ah..

I was planning on using J's memory allocation routines (perhaps jtgafv?).

Those libgmp low level functions are low-level functions which do not
perform any memory allocation. For example: mpn_add_n adds two
integers but requires memory allocation to be performed elsewhere.

This is what would allow us (me) to use J's memory allocation routines.

I hope this makes sense.

And, I guess I should dive in and try something. If nothing else, to
see what breaks... (I've made some small preparatory experiments, but
I could obviously do a lot more.)

--
Raul

On Tue, Oct 24, 2023 at 1:44 PM Henry Rich <[email protected]> wrote:
>
> You referred to a page on low level functions. I don't see how it applies
> to allocation.
>
> hhr
>
> On Tue, Oct 24, 2023, 4:15 PM Raul Miller <[email protected]> wrote:
>
> > I've lost track of the thread here.
> >
> > Could you expand your question?
> >
> > Thanks,
> >
> > --
> > Raul
> >
> > On Tue, Oct 24, 2023 at 11:08 AM Henry Rich <[email protected]> wrote:
> > >
> > > I don't see a memory allocator among the functions. How does this page
> > help
> > > with allocations?
> > >
> > > hhr
> > >
> > > On Mon, Oct 23, 2023, 6:10 PM Eric Iverson <[email protected]>
> > wrote:
> > >
> > > > I think gmp has proven itself and the cleanup you suggest would be
> > > > worthwhile.
> > > >
> > > > On Sun, Oct 15, 2023 at 11:12 AM Raul Miller <[email protected]>
> > > > wrote:
> > > >
> > > > > Some time ago, Elijah Stone pointed out that using
> > > > > https://gmplib.org/manual/Low_002dlevel-Functions we could use J's
> > > > > memory management routines directly, without having to deal with
> > > > > libgmp's "exit the program if the library can't allocate memory"
> > > > > behavior.
> > > > >
> > > > > This seems like it would be a good thing for us. When completed, we
> > > > > could eliminate the memory pool currently used when handling extended
> > > > > values, and we could also relax the current limit placed on the
> > > > > magnitude of extended values.
> > > > >
> > > > > But changing everything all at once is a good way to never get
> > started.
> > > > >
> > > > > So, it's worth thinking about how we could organize this kind of
> > effort.
> > > > >
> > > > > Currently, the code is partitioned in three chunks: libgmp itself (or
> > > > > mpir on windows), the jgmp.h/jgmpinit.h glue, and macros defined in
> > > > > jgmp.h which are used in most of the rest of the system. (There's
> > also
> > > > > a few direct calls to libgmp functions in k.c, v2.c, vq.c, vx.c and
> > > > > wn.c)
> > > > >
> > > > > So, conceptually speaking, we could implement workalikes for these
> > > > > macros (things like XaddXX() which rely on the lower level mpn_
> > > > > functions instead of the problematic mpz_ / mpq_ functions. (We could
> > > > > replace the direct calls with suitable macros, along the way. (Or, if
> > > > > there's cases where there's really a significant performance
> > > > > advantage, we could replace them with suitable direct calls to the
> > > > > memory management routines and mpn_ functions. But this seems
> > > > > unlikely.))
> > > > >
> > > > > The trick would be allowing XNUM and RAT values whose memory was
> > > > > allocated via libgmp to coexist with XNUM and RAT values whose memory
> > > > > was allocated using J's memory manager. The details here are a bit
> > > > > annoying, but fundamentally we've already provided for this.
> > > > >
> > > > > Basically, the distinction matters when we free the memory. And, that
> > > > > decision is based on FHRHISGMP==AFHRH(x) vs FHRHISGMP!=AFHRH(x) in
> > > > > jgmp.h and jgmpinit.c
> > > > >
> > > > > -----------------------------------------------
> > > > >
> > > > > So.. it seems to me that if we created a parallel glue rig -- maybe
> > > > > jgmpn.h -- we could start migrating functionality to the mpn_* family
> > > > > of functions and J's "native" memory management. XaddXX() seems like
> > > > > the place to start.
> > > > >
> > > > > I would need to figure out how to deal with the "realloc" cases where
> > > > > the amount of memory required for a calculation (like multiply or
> > > > > format) might be larger or smaller - perhaps significantly larger -
> > > > > than the memory needed to represent the result.
> > > > >
> > > > > But, once started, the work could proceed gradually. As long as the
> > > > > primitives continue to function, users mostly wouldn't notice the
> > > > > changes. (And, ok, that sounds discouraging. But hopefully the end
> > > > > result would be worth it.)
> > > > >
> > > > > Thoughts?
> > > > >
> > > > > My thought is that this kind of code cleanup seems worthwhile.
> > > > >
> > > > > Thanks,
> > > > >
> > > > > --
> > > > > Raul
> > > > >
> > ----------------------------------------------------------------------
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