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Re: [Stds-754] revised motion #18 for July 19-20
David has revised item 18. - Dan
Date: Fri, 14 Jul 2006 13:41:16 -0700 (PDT)
From: David Hough 754R work <754r@xxxxxxxxxxx>
Subject: [Stds-754] revised motion #18 for July 19-20
Revised to fit current draft:
Motion: Delete scaledprod operation from 7; add E.5. Scaled-product operations
Rationale:
The current specification is too limited to be worth standardizing.
Actual applications are just as likely to need over/underflow
protection for products of sums and differences. And the array
versions would not likely be implemented upon a primitive with the prescribed
semantics (a more probable implementation primitive would return zero sf if
no over/underflow intervenes, and would leave sf undefined if there were
an invalid operation). Since the whole point is performance,
the user feature (acting on arrays) would be implemented upon a performant
primitive.
So restore the actual user feature to annex E, which is where it came from
originally, as a means of avoiding specifying counting mode.
Text:
Delete scaledprod operation from 7.3.3 in the 754R draft.
Add E.5 Scaled-product operations by copying 5.3.2 Scaled-product operations
from http://754r.ucbtest.org/motions/archive/chapter5.pdf