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checksums.superfast: reuse more code, slightly faster for non-byte-arrays.

db4
John Benediktsson 2013-11-24 09:58:02 -08:00
parent 77d2abc06c
commit 627993fc1a
1 changed files with 11 additions and 15 deletions
basis/checksums/superfast

26
basis/checksums/superfast/superfast.factor
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@ -12,24 +12,23 @@ C: <superfast> superfast
<PRIVATE
: 16-bit ( n -- n' ) 16 on-bits mask ; inline
: 32-bit ( n -- n' ) 32 on-bits mask ; inline
: (main-loop) ( hash m n -- hash' )
: (main-loop) ( hash n -- hash' )
[ 16-bit ] [ -16 shift ] bi
[ + ] [ 11 shift dupd bitxor ] bi*
[ 16 shift ] [ bitxor ] bi* 32-bit
[ -11 shift ] [ + ] bi ; inline
: main-loop ( seq hash -- seq hash' )
over byte-array? little-endian? and [
[ 0 over length 4 - 4 <range> ] dip [
pick <displaced-alien> int deref
[ 16 on-bits mask ] [ -16 shift ] bi
(main-loop)
] reduce
[ 0 over length 4 - 4 <range> ] dip
[ pick <displaced-alien> int deref (main-loop) ] reduce
] [
[ dup length 4 mod dupd head-slice* 4 <groups> ] dip [
2 cut-slice [ le> ] bi@ (main-loop)
] reduce
[ dup length 4 mod dupd head-slice* 4 <groups> ] dip
[ le> (main-loop) ] reduce
] if ; inline
: end-case ( seq hash -- hash' )
@ -52,12 +51,9 @@ C: <superfast> superfast
} dispatch ; inline
: avalanche ( hash -- hash' )
[ 3 shift ] [ bitxor ] bi 32-bit
[ -5 shift ] [ + ] bi
[ 4 shift ] [ bitxor ] bi 32-bit
[ -17 shift ] [ + ] bi
[ 25 shift ] [ bitxor ] bi 32-bit
[ -6 shift ] [ + ] bi ; inline
[ 3 shift ] [ bitxor ] bi 32-bit [ -5 shift ] [ + ] bi
[ 4 shift ] [ bitxor ] bi 32-bit [ -17 shift ] [ + ] bi
[ 25 shift ] [ bitxor ] bi 32-bit [ -6 shift ] [ + ] bi ; inline
PRIVATE>