Re: Idle curiosity (ieee bitorder)

BRG wrote:
> What convention?

I say "do a shift which doubles the value in a register"

is that

x = x >> 1

or

x = x << 1

????

It's really that simple. "rightshift" is their way of writing
"multiply by x" which is typically analogous to multiplying by 2.

So with that in mind for GCM and LRW you have to load the bytes in big
endian and do right shifts to "double" the value. But the first byte
is not the actual MSbyte ...

in normal representation you'd load it in little endian and do a left
shift to double it.

Tom

.

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