RFR: 8240615: is_power_of_2() has Undefined Behaviour and is inconsistent

[John Rose]

On Mar 6, 2020, at 9:11 AM, Andrew Haley <aph at redhat.com> wrote:
> 
> +  predicate(is_power_of_2((julong)n->get_long()));

To me this is an easy “yes”.  The hardware instruction in question
uses the unsigned convention.

The harder part is (as you say) figuring out where we were implicitly
relying on unsigned conventions and behavior will change.  But I
think we’ve had plenty of eyeballs on this, and it’s easy to fix more
stuff like this if we find it later, right?

— John