cpplib: expression parser patch 2

[Zack Weinberg]

On Sun, Apr 02, 2000 at 02:55:54PM +0200, Gerald Pfeifer wrote:
> On Sun, 2 Apr 2000, Neil Booth wrote:
> > I've also discovered that gcc optimizes
> > 
> > unsignedp = unsigned1 || unsigned2;
> > 
> > very poorly. Since the "unsigned" variables can only be 0 or 1 (I've
> > checked), my next patch will include the change of these lines to
> > 
> > unsignedp = unsigned1 | unsigned2;
> 
> I think the better approach would be to fix GCC instead of playing
> coding tricks.

I bet the code will mysteriously improve if you compile it with
-mbranch-cost-2.  GCC does know how to optimize (a || b) to (a | b)
but doesn't do it if it thinks branches are dirt cheap.  The i386 port
says branches are dirt cheap for some reason.

Please try that before making this change.

zw