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On modern CPU, byte-level addressing is but smoke and mirrors for what is a fetch of a line-sized memory chunk followed by a mask-and-shift.


Not at the ISA level. Programmers don’t have access to the smoke and mirrors besides some cache management stuff


Depends on the cpu specific, and a lot of non-x86 designs made it explicit that memory is not byte addressable without special steps.

This makes those architectures incompatible with latest C and C++ though, because they require simultaneous, concurrent, atomic access to bytes at a time


The most important non x86 arch is aarch64 which is in fact byte addressable (more so than x86)! So is mips64.


Using c on a word machine is just a bad idea.


But x86_64 ISA is smoke and mirrors; proof is the large increase in performances that can obtained when one is aware of these tricks.




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