(j3.2006) BEQ, BNE?

[Van Snyder]

On Tue, 2013-01-29 at 19:54 -0800, Robert Corbett wrote:
> On 01/29/13 18:22, Van Snyder wrote:
> > We did BLT, BLE, etc., but why not BEQ and BNE?
> >
> > One might be tempted to use == and /=, but these are required to fail
> > for +/- zero on ones-complement and sign-magnitude machines because
> > Fortran doesn't distinguish +0 from -0 for integers.
> >
> > Should we add BEQ and BNE, or suggest that users write something like
> >
> >    if ( BLE(I,J) .and. BLE(J,I) ) then ! I and J are equal bit strings
> >      ....
> >    end if
> >
> > or is there another way to do it that I've overlooked?
> 
> I prefer
> 
> 
>        IF ( POPCNT(IEOR(I, J)) .EQ. 0) THEN ! I and J are equal bit strings

Sounds more expensive than BEQ(I,J) would be on architectures that can
do an unsigned integer compare but don't have a fast POPCNT.

> Bob Corbett
> 
> 
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