On Tue, Sep 30, 2025 at 04:08:56PM -0000, Greg wrote:
In computing, a word is any processor design's natural unit of data. A word is
a fixed-sized datum handled as a unit by the instruction set or the hardware of
the processor.
It has that definition (among others), one which mapped cleanly to
historic processors, but which is much messier when dealing with modern
CPUs. E.g., amd64 mostly has 64bit instruction operands and types, but
there's also an 80 bit floating point type and with AVX-512 extensions
has 512 bit registers and can transfer data to/from memory 512 bits at a
time in a single instruction. So is the word size 512? 80? 64?
Conversely, if someone confidently says "its word size is 64", what does
that tell you/what can you do with that information? If it's a term
divorced from practical applications then it's just a historical
curiosity. If someone has to add a bunch of asterisks and explain away
functionality that doesn't cleanly fit into the model, how relevant is
the model?
