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C++ proposal: There are exactly 8 bits in a byte

(www.open-std.org)
182 points Twirrim | 4 comments | 17 Oct 24 22:21 UTC | HN request time: 0.572s | source
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throwaway889900 ◴[17 Oct 24 23:18 UTC] No.41874794[source]▶
But how many bytes are there in a word?
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wvenable ◴[17 Oct 24 23:27 UTC] No.41874838[source]▶
"Word" is an outdated concept we should try to get rid of.
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pclmulqdq ◴[17 Oct 24 23:32 UTC] No.41874888[source]▶
It's very useful on hardware that is not an x86 CPU.
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1. wvenable ◴[17 Oct 24 23:39 UTC] No.41874937[source]▶
As an abstraction on the size of a CPU register, it really turned out to be more confusing than useful.
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2. bobmcnamara ◴[17 Oct 24 23:49 UTC] No.41874993[source]▶
Is it 32 or 64 bits on ARM64? Why not both?
3. o11c ◴[17 Oct 24 23:51 UTC] No.41875003[source]▶
Fortunately we have `register_t` these days.
4. pclmulqdq ◴[18 Oct 24 00:02 UTC] No.41875078[source]▶
On RISC machines, it can be very useful to have the concept of "words," because that indicates things about how the computer loads and stores data, as well as the native instruction size. In DSPs and custom hardware, it can indicate the only available datatype.

The land of x86 goes to great pains to eliminate the concept of a word at a silicon cost.