Re: Shrinking the C core

[Ihor Radchenko]

Ihor Radchenko <yantar92@posteo.net> writes:

> The only problem (AFAIU) is that GCC JIT cannot reach inside subr level,
> so all these information does not benefit Emacs functions implemented in
> C.

If I am right here, it might actually be worth it to rewrite some of the
subroutines into Elisp. For example rounding_driver (called by
`floor') code is full of runtime type checks:

  CHECK_NUMBER (n);
  if (NILP (d))
...
  CHECK_NUMBER (d);
...
  if (FIXNUMP (d))
      if (XFIXNUM (d) == 0)
...
      if (FIXNUMP (n))
...
  else if (FLOATP (d))
      if (XFLOAT_DATA (d) == 0)
  int nscale = FLOATP (n) ? double_integer_scale (XFLOAT_DATA (n)) : 0;
..

During native compilation, if type information and n and d is available,
GCC might have a chance to cut a number of branches away from the above
code.

-- 
Ihor Radchenko // yantar92,
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