On Tuesday 21 March 2006 21:59, Jeffrey A Law wrote:
> On Tue, 2006-03-21 at 10:14 +0100, Duncan Sands wrote:
>
> > Hi Jeff, on the subject of seeing through typecasts, I was playing around
> > with VRP and noticed that the following "if" statement is not eliminated:
> >
> > int u (unsigned char c) {
> > int i = c;
> >
> > if (i < 0 || i > 255)
> > return -1; /* never taken */
> > else
> > return 0;
> > }
> >
> > Is it supposed to be?
> Fixed thusly. Bootstrapped and regression tested on i686-pc-linux-gnu.
Hi Jeff, this seems to work nicely - thanks again. I still see a bunch
of suboptimal range calculations in the Ada code I'm looking at, but these
now just coming from having everything initialised to VR_VARYING rather than
[TYPE_MIN, TYPE_MAX]. Do you know of any way of getting variables with
non-trivial TYPE_MIN/TYPE_MAX values in C? I ask because I'd rather produce
test cases in C than Ada, since everyone has access to a C compiler :)
All the best,
Duncan.
