On 2014-11-04, at 05:54, Peter Relson wrote: > > Since the construct pre-dated long-displacement, it's quite possible that > it means very little with respect to long displacement. Or perhaps, for > long displacement, the "end" is to some extent ignored (although it might > be used to select from among multiple choices). > ... > As opposed to > USING (*,*+1000),RegA > USING *+1000,RegB > It seems to me to be even more important to enforce END with long displacements because in many cases base register combinations which produce unique resolutions with 12-bit displacements may produce ambiguous resolutions with long displacements.
I suspect that HLASM development merely overlooked the design changes necessary to accommodate long displacements fully. -- gil
