Given the compression stuff is an extension (and so far as I can tell the 16-bit alignment for 32-bit instructions that can result in that sort of spanning is p

Given the compression stuff is an extension (and so far as I can tell the 16-bit alignment for 32-bit instructions that can result in that sort of spanning is part of that extension), so far as I can tell you could implement said extension for tiny hardware where every byte counts, and then for hardware where you're wanting to fetch 8+ instructions per cycle just ... not implement it? Wait (he says to himself, realising he's an idiot immediately -before- posting the comment for once). You said upthread the C extension is specified as part of the standard UNIX profile, so I guess people are effectively required to implement it currently? If that was changed, would that be sufficient to dissolve the issues for people wanting to design high performance implementations, or are there other problems inherent to the extension having been specified at all? (apologies for the 101 level questions, the only processor I really understood was the ARM2 so my curiosity vastly exceeds my knowledge here)