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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
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