Extend widening_mul pass to handle fixed-point types

[Bernd Schmidt]

On 07/19/2010 08:34 PM, Richard Sandiford wrote:
> I did wonder about splitting the stuff out into a separate function.
> The advantage of not doing is that it avoids duplicate work in cases
> where we visit the macc first, and where the WIDEN_MULT_EXPR _can_
> be used.  I thought that would be quite a common case.

Not sure about that - normally I'd expect the multiply and add to appear
roughly in the order they're executed.

> Here's a version that splits it out and drops the two-at-once thing.
> Only lightly tested, but does it look better?

That's pretty much what I had in mind.  Ok if it passes testing.


Bernd