I think the decision of Tom Ross and his colleagues to first exploit
DFP in compiler-generated code is a defensible, entirely appropriate
one.

It is an open secret that few COBOL implementations do packed-decimal
arithmetic of any real complexity in packed decimal.  Historically,
they have converted packed-decimal operands into floating-point ones,
done the non-trivial arithmetic using register-oriented (as opposed to
storage-to-storage) floating-point instructions, and then converted
the floating-point results back into fixed-point ones.  All of these
operations, and in particular the conversions, are greatly facilitated
by the availability of DFP-to-and-from-packed-decimal conversion
machine instructions.

Insurance and banking applications that do non-trivial arithmetic will
benefit significantly from this change, which eliminates the need for
post processing HFP results to ensure that they do not surprise users
and users' customers.  Better performance without source-program
changes is highly desirable, and this use of DFP provides it.

This said---as Tom surely knows---the pressure to make DFP directly
available to Enterprise COBOL applications programmers will now grow.

John Gilmore, Ashland, MA 01721 - USA

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