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-This is a patched version of zlib modified to use
-Pentium-optimized assembly code in the deflation algorithm. The files
-changed/added by this patch are:
-
-README.586
-match.S
-
-The effectiveness of these modifications is a bit marginal, as the the
-program's bottleneck seems to be mostly L1-cache contention, for which
-there is no real way to work around without rewriting the basic
-algorithm. The speedup on average is around 5-10% (which is generally
-less than the amount of variance between subsequent executions).
-However, when used at level 9 compression, the cache contention can
-drop enough for the assembly version to achieve 10-20% speedup (and
-sometimes more, depending on the amount of overall redundancy in the
-files). Even here, though, cache contention can still be the limiting
-factor, depending on the nature of the program using the zlib library.
-This may also mean that better improvements will be seen on a Pentium
-with MMX, which suffers much less from L1-cache contention, but I have
-not yet verified this.
-
-Note that this code has been tailored for the Pentium in particular,
-and will not perform well on the Pentium Pro (due to the use of a
-partial register in the inner loop).
-
-If you are using an assembler other than GNU as, you will have to
-translate match.S to use your assembler's syntax. (Have fun.)
-
-Brian Raiter
-breadbox@muppetlabs.com
-April, 1998
-
-
-Added for zlib 1.1.3:
-
-The patches come from
-http://www.muppetlabs.com/~breadbox/software/assembly.html
-
-To compile zlib with this asm file, copy match.S to the zlib directory
-then do:
-
-CFLAGS="-O3 -DASMV" ./configure
-make OBJA=match.o