RFA: Add builtin bitcounting bitops for xstormy16

[Richard Henderson]

On Fri, Sep 02, 2005 at 09:22:47AM +0100, Nick Clifton wrote:
> + static const unsigned char __popcount_tab[] =

Why are you replicating this table?  It's already present in libgcc2.c,
emitted to its own object file.

> +   return __ctzsi2 (y << 16) - 16;
...
> +   return __clzsi2 (x) - 16;

See longlong.h.  You can simplify these fairly well for fewer bits.

unsigned int __clzhi2 (unsigned int x)
{
  if (x > 0xff)
    return __clz_tab[x >> 8];
  else
    return __clz_tab[x] + 8;
}

unsigned int __ctzhi2 (unsigned int x)
{
  x = x & -x;
  if (x > 0xff)
    return 15 - __clz_tab[x >> 8];
  else
    return 7 - __clz_tab[x];
}


r~