faster rand(UInt64) and rand(UInt128) #9083
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The function rand_ui32 is removed, and rand_ui_52_raw, which consumes
one Float64 like rand_ui32, is used instead in the implementation of
rand{T<:IntTypes}(::Type{T}).
Consequently, rand(UInt128) consumes only 3 random Float64 instead of 4.
It seems that rand(UInt64) is also slightly faster.
A function reserve(::MersenneTwister) is called before rand_inbounds: so only one bound check is done instead of two (resp. three) for UInt64 (resp. UInt128).
ViralBShah
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Nov 20, 2014
faster rand(UInt64) and rand(UInt128)
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On my machine,
rand(UInt64)becomes 30%-40% faster, andrand(UInt128)about 110% faster.