mirror of
https://git.do.srb2.org/STJr/SRB2.git
synced 2024-12-23 11:10:56 +00:00
52 lines
1.6 KiB
Text
52 lines
1.6 KiB
Text
|
This is a patched version of zlib, modified to use
|
||
|
|
Pentium-Pro-optimized assembly code in the deflation algorithm. The
|
||
|
|
files changed/added by this patch are:
|
||
|
|
|
||
|
|
README.686
|
||
|
|
match.S
|
||
|
|
|
||
|
|
The speedup that this patch provides varies, depending on whether the
|
||
|
|
compiler used to build the original version of zlib falls afoul of the
|
||
|
|
PPro's speed traps. My own tests show a speedup of around 10-20% at
|
||
|
|
the default compression level, and 20-30% using -9, against a version
|
||
|
|
compiled using gcc 2.7.2.3. Your mileage may vary.
|
||
|
|
|
||
|
|
Note that this code has been tailored for the PPro/PII in particular,
|
||
|
|
and will not perform particuarly well on a Pentium.
|
||
|
|
|
||
|
|
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
|
||
|
|
|
||
|
|
|
||
|
|
Update:
|
||
|
|
|
||
|
|
I've been ignoring these assembly routines for years, believing that
|
||
|
|
gcc's generated code had caught up with it sometime around gcc 2.95
|
||
|
|
and the major rearchitecting of the Pentium 4. However, I recently
|
||
|
|
learned that, despite what I believed, this code still has some life
|
||
|
|
in it. On the Pentium 4 and AMD64 chips, it continues to run about 8%
|
||
|
|
faster than the code produced by gcc 4.1.
|
||
|
|
|
||
|
|
In acknowledgement of its continuing usefulness, I've altered the
|
||
|
|
license to match that of the rest of zlib. Share and Enjoy!
|
||
|
|
|
||
|
|
Brian Raiter
|
||
|
|
breadbox@muppetlabs.com
|
||
|
|
April, 2007
|