hash-prospector
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Any interest in CLMUL and XROT2?
Are there any plans or is there any interest at all in having
-
CLMUL
, the carryless multiplication which has its own opcode on modern CPUs, and -
XROT2
, that is the invertible double xor rotatex ^= (x >>> a) ^ (x >>> b)
,
implemented?
I would expect CLMUL
to have slightly less influence on bias than a regular integer multiplication due to the lack of carry's left-bound "smearing" effect.
XROT2
should show an effect on lowering bias which I would assume somewhere between one and two xor-shifts – remains to be proven. Execution on super-pipelined CPUs could speed-wise benefit from working on the very same x
being rotated twice. However, little coding challenge here: two parameters a
and b
need to be parsed from command line's -p
pattern.