[Zlib-devel] [PATCH] deflate.c: identify slide_Pos() for later optimization

[John Reiser]

On 07/24/2012 02:26 AM, Jan Seiffert wrote:

> https://github.com/kaffeemonster/zlib/commit/aa30d206d93755c1f5c287b78dd7d165fb0998a8
   etc.

Thank you for the code!  Where are the discussion threads about such optimizations?

> And no, most compiler do not get it that this is a subtraction with saturation.

I suggested "a very good compiler".  I have worked with a large handful of
compilers of different origins, and only one has been good enough [a compiler
for APL.]  On the other hand, subtraction with saturation was a primitive [library]
routine in Fortran II (1958): MIN0, DMIN0, etc.; and I have used those.  So this
looks like a case of lost or discarded history.

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