Re: switch index optimization

[Richard Henderson <rth at cygnus dot com>]

On Sun, Jan 25, 1998 at 11:01:48PM -0800, Joe Buck wrote:
> Not a bad idea, but kind of an unclean implementation.

Guilty.

> But to do really well, range propagation needs to be done with dataflow
> analysis (though in this case you can do it without).

Thus my comment about maybe doing it in jump.  It does some of
that sort of thing, and I am half-remembering Jeff doing some
work recently in that area for <censored>, such that

	if (x < 7) {
		if (x == 9) { }
	}

and similar get optimized properly.

Ah well, perhaps I'll clean up what I was doing, and if someone does
do the Right Thing elsewhere later, we can strip mine back out.


r~