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| author | Jelmer Vernooij <jelmer@samba.org> | 2008-10-21 14:51:13 +0200 |
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| committer | Jelmer Vernooij <jelmer@samba.org> | 2008-10-21 14:51:13 +0200 |
| commit | 5209a846a9157e649fcdcb561f7eaf19c8c0e465 (patch) | |
| tree | b0a7e52b5646c8eec182dbc391e7934b6804488c /lib/zlib/contrib/asm586/README.586 | |
| parent | 625359b2e266105022309df8985720108ecd6f67 (diff) | |
| parent | 2ee8d29d22bcb1c350ab59d71b0aee548489bc9c (diff) | |
| download | samba-5209a846a9157e649fcdcb561f7eaf19c8c0e465.tar.gz samba-5209a846a9157e649fcdcb561f7eaf19c8c0e465.tar.bz2 samba-5209a846a9157e649fcdcb561f7eaf19c8c0e465.zip | |
Merge branch 'master' of ssh://git.samba.org/data/git/samba into regsrv
Conflicts:
source4/lib/registry/ldb.c
source4/rpc_server/winreg/rpc_winreg.c
Diffstat (limited to 'lib/zlib/contrib/asm586/README.586')
| -rw-r--r-- | lib/zlib/contrib/asm586/README.586 | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/lib/zlib/contrib/asm586/README.586 b/lib/zlib/contrib/asm586/README.586 new file mode 100644 index 0000000000..6bb78f3206 --- /dev/null +++ b/lib/zlib/contrib/asm586/README.586 @@ -0,0 +1,43 @@ +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 |