On Fri, Jun 24, 2011 at 6:58 PM, Stubbs, Andrew <andrew_stu...@mentor.com> wrote: > On 24/06/11 16:47, Richard Guenther wrote: >>> > I can certainly add checks to make sure that the skipped operations >>> > actually don't make any important changes to the value, but do I need to? >> Yes. > > Ok, I'll go away and do that then. > > BTW, I see useless_type_conversion_p, but that's not quite what I want. > Is there an equivalent existing function to determine whether a > conversion changes the logical/arithmetic meaning of a type? > > I mean, conversion to a wider mode is not "useless", but it is harmless, > whereas conversion to a narrower mode may truncate the value.
Well, you have to decide that for the concrete situation based on the signedness and precision of the types involved. All such conversions change the logical/arithmetic meaning of a type if seen in the right context. Richard. > Andrew >
