[julia-users] C function vs 64 bit arithmetic in julia

[Forrest Curo]

I want to turn an unsigne64 into bytes, chew on the bytes, & rearrange into
a new unsigned64.

Should I expect significant gain by reading it into a C function to make it
a union of char and unsigned64, take out the chars & put the new ones back
into that union --

or should it be close enough in speed to stay in julia,
with something like:

for i = 1:8
 bites[i] = x & 255
 x >>= 8
end

[doing stuff to bites]

x = 0
for i = 1:8
 x += bites[i]
end
?