Re: [PATCH] Speed-up sprintf() family of functions.

[Jonathan Larmour <jifl at eCosCentric dot com>]

Sergei Organov wrote:
> Jonathan Larmour <jifl@eCosCentric.com> writes:
>
> > Sergei Organov wrote:
> > > > Oh yes, I know there's a lot of things I would do very differently
> > > > given the chance and the benefit of 10 more years of experience. There
> > > > are many, many places the code could be improved (or rewritten!), and
> > > > that is one.
>
> Does anybody actually work on improving those things? From outside it
> looks like kernel and libc development is stopped.

It's just a question of priorities. It's not terribly surprising that this 
is lower down the list, and doesn't mean everything's wonderful now.

> > > I think I need to experiment on this then. Hopefully this eCos part is
> > > usually compiled without -fno-builtins?
> > Correct. The only times -fno-builtin is used normally is when we know
> > GCC is buggy in some area (and therefore usually only temporarily).
>
> No luck. GCC (I checked 4.0.2 for ARM) just calls memcpy() when the
> number of bytes to copy is not a constant. For typically small sizes, I
> think direct loop is still faster, and the initial rationale still
> applies.

Huh, I thought GCC was better than that. Okay, looks like you made the 
right choice then!

> > > > Hmm, that kernel change did seem big enough to need one in my view. I
> > > > think someone may have dropped the ball there. We would want an
> > > > assignment for that, irrespective of this libc stdio change.
> > >
> > > What kernel change are you talking about?
> > It was the kernel change I referred to earlier in the thread. This one:
> >
> >  2006-04-10  Sergei Organov  <osv@javad.com>
> >
> >         Implement FIFO variant of scheduling of DSRs and make it the
> >         default. This is reworked patch originally suggested by Stefan
> >         Sommerfeld <sommerfeld@mikrom.com>.
>
> Ah, those. So I was unlucky to send my patch before Stefan's has been
> accepted ;) I myself consider that one trivial, being "common
> knowledge", and mostly copy-pasted from pre-existing code.
>
> Still wish to get an assignment?

Stefan doesn't have an assignment either, but I think your version is the 
only one that really needs the assignment since not very much of his 
original stuff remains.

Anyway, the patch is a whole is sufficient to be a copyrightable work, so 
yes please, do arrange an assignment. Assuming this will come before too 
long, I won't revert the patch now.

Jifl
--
--["No sense being pessimistic, it wouldn't work anyway"]-- Opinions==mine