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Re: Bit twiddling builtins
Richard Henderson <rth@redhat.com> writes:
> On Mon, Jan 27, 2003 at 07:08:43PM +0100, Falk Hueffner wrote:
> > > (1) Refuse to widen CLZ, no matter what. This requires all targets
> > > to implement CLZ in all sizes they want to use it in.
> > >
> > > (2) Have optabs account for this by transforming:
> > >
> > > (clz:narrow x)
> > > to
> > > (clz:wide (zero_extend:wide x)) - ((width wide) - (width narrow))
> >
> > I would like to do this, but I can't find the proper place to put
> > it. Can you give me a hint?
>
> Immediately before
> [...]
>
> For (2) you'd make your own for loop. If you do this, please do it
> in a new function; expand_binop is way too big as it is.
Are you sure it's not rather the corresponding place in expand_unop?
--
Falk