3 ms·
On modern CPUs, it used not to be something to care about in the past across 8, 16, 32 bit generations, outside RISC.
by pjmlp 8mo ago
On modern CPUs, it used not to be something to care about in the past across 8, 16, 32 bit generations, outside RISC.
- inkyoto 8mo agoPDP-11, m68k – to name a few, did not allow misaligned access to anything that was not a byte. Neither are RISC nor modern.
- pjmlp 8mo agoIn regards to 68000 I don't remember, only used it during demoscene coding parties when allowed to touch Amiga from my friends. I have only seen PDP-11 Assembly snippets in UNIX related books, wasn't aware of its alignment requirements.
- inkyoto 8mo agoPDP-11 was a major source of inspiration for m68k architecture designers. The influence can be seen in multiple places, starting from the orthogonal ISA design down to instruction mnemonics. It is quite likely that not allowing the misaligned access was also influenced by PDP-11.