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c0ff5f4dd7
Previous implementation had an issues: - macros murmur1 assumes murmur_step takes rotation value as a second argument - but murmur_step second argument is "next block" - this makes st_hash_uint and st_hash_end to not mix high bits of hash value into lower bits - this leads to pure hash behavior on doubles and mixing hashes using st_hash_uint. It didn't matter when bins amount were prime numbers, but it hurts when bins are powers of two. Mistake were created cause of attempt to co-exist Murmur1 and Murmur2 in a same code. Change it to single hash-function implementation. - block function is in a spirit of Murmur functions, but handles inter-block dependency a bit better (imho). - final block is read in bit more optimal way on CPU with unaligned word access, - final block is mixed in simple way, - finalizer is taken from MurmurHash3 (it makes most of magic :) ) (64bit finalizer is taken from http://zimbry.blogspot.ru/2011/09/better-bit-mixing-improving-on.html) Also remove ST_USE_FNV1: it lacks implementation of many functions, and looks to be abandoned Author: Sokolov Yura aka funny_falcon <funny.falcon@gmail.com> git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57134 b2dd03c8-39d4-4d8f-98ff-823fe69b080e |
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| .. | ||
| backward | ||
| backward.h | ||
| debug.h | ||
| defines.h | ||
| encoding.h | ||
| intern.h | ||
| io.h | ||
| missing.h | ||
| onigmo.h | ||
| oniguruma.h | ||
| re.h | ||
| regex.h | ||
| ruby.h | ||
| st.h | ||
| subst.h | ||
| thread.h | ||
| thread_native.h | ||
| util.h | ||
| version.h | ||
| vm.h | ||
| win32.h | ||