diff options
| author | Henri Beauchamp <sldevel@users.noreply.github.com> | 2023-01-31 17:42:51 +0100 |
|---|---|---|
| committer | Andrey Kleshchev <andreykproductengine@lindenlab.com> | 2023-01-31 22:04:14 +0200 |
| commit | 473ade269628d1fb6cbc7b96a91e1c0aec1b8e59 (patch) | |
| tree | 5e3347164dbffdb8c73b9a58c94fff75eb221aac /indra/cmake | |
| parent | c154f4f6da10df693cbe15e0fe291d5b3c423d32 (diff) | |
SL-19110 Fast hashing classes for use in place of the slow LLMD5, where speed matters. (#64)
This commit adds the HBXX64 and HBXX128 classes for use as a drop-in
replacement for the slow LLMD5 hashing class, where speed matters and
backward compatibility (with standard hashing algorithms) and/or
cryptographic hashing qualities are not required.
It also replaces LLMD5 with HBXX* in a few existing hot (well, ok, just
"warm" for some) paths meeting the above requirements, while paving the way for
future use cases, such as in the DRTVWR-559 and sibling branches where the slow
LLMD5 is used (e.g. to hash materials and vertex buffer cache entries), and
could be use such a (way) faster algorithm with very significant benefits and
no negative impact.
Here is the comment I added in indra/llcommon/hbxx.h:
// HBXXH* classes are to be used where speed matters and cryptographic quality
// is not required (no "one-way" guarantee, though they are likely not worst in
// this respect than MD5 which got busted and is now considered too weak). The
// xxHash code they are built upon is vectorized and about 50 times faster than
// MD5. A 64 bits hash class is also provided for when 128 bits of entropy are
// not needed. The hashes collision rate is similar to MD5's.
// See https://github.com/Cyan4973/xxHash#readme for details.
Diffstat (limited to 'indra/cmake')
| -rw-r--r-- | indra/cmake/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | indra/cmake/LLCommon.cmake | 1 | ||||
| -rw-r--r-- | indra/cmake/xxHash.cmake | 8 |
3 files changed, 10 insertions, 0 deletions
diff --git a/indra/cmake/CMakeLists.txt b/indra/cmake/CMakeLists.txt index 4d70089737..fb3c7216c7 100644 --- a/indra/cmake/CMakeLists.txt +++ b/indra/cmake/CMakeLists.txt @@ -91,6 +91,7 @@ set(cmake_SOURCE_FILES VisualLeakDetector.cmake LibVLCPlugin.cmake XmlRpcEpi.cmake + xxHash.cmake ZLIBNG.cmake ) diff --git a/indra/cmake/LLCommon.cmake b/indra/cmake/LLCommon.cmake index 53871791fd..528b43c3fc 100644 --- a/indra/cmake/LLCommon.cmake +++ b/indra/cmake/LLCommon.cmake @@ -4,6 +4,7 @@ include(APR) include(Boost) include(EXPAT) include(Tracy) +include(xxHash) include(ZLIBNG) set(LLCOMMON_INCLUDE_DIRS diff --git a/indra/cmake/xxHash.cmake b/indra/cmake/xxHash.cmake new file mode 100644 index 0000000000..a7c1cba62c --- /dev/null +++ b/indra/cmake/xxHash.cmake @@ -0,0 +1,8 @@ +# -*- cmake -*- +if (XXHASH_CMAKE_INCLUDED) + return() +endif (XXHASH_CMAKE_INCLUDED) +set (XXHASH_CMAKE_INCLUDED TRUE) + +include(Prebuilt) +use_prebuilt_binary(xxhash) |