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CWP Software Update: 10/25/91  (15th edition)

Dave Hale upgraded the conv and xcor functions in libcwp.
Because the effect is so dramatic, we have updated cwp.tar.Z to
reflect this.  Caveat Emptor:  we haven't done a test install, but
with just two lib routines changed, what could go wrong?  :-)

Here are some comments by Dave:
---------
The new conv is optimized for machines such as the RS/6000
(and others) that can do a multiply, an add, and one
load from memory simultaneously.  The new conv goes
at near peak performance on our RS/6000s (over twice
as fast as the old conv) and is about 10% faster
on our NeXTs.

The bad news is that the new conv is about 1400 lines
of code.  Therefore, the new xcor simply calls conv.
This keeps us from having two 1400 line functions to
maintain.
---------
Note: to obtain peak performance on the IBM RS/6000,
you have to add the compiler flag -qxflag=hsflt
to CFLAGS in the libcwp Makefile.
IN THE INTERESTS OF PORTABILITY, THE DISTRIBUTED MAKEFILE
DOES NOT CONTAIN THIS FLAG!