u/Azzimihr

If the encoding space for 32-bit instructions is getting tight (which is apparently a concern?), why would it not make sense for the encoding of 48-bit instructions to be slanted one further bit to the left by using 0111111 to mark the beginning instead of 011111? From what I can tell this should double the number of available major opcodes for 32-bit instructions (the most common case), fits neatly in the 7-bit opcode segment and is barely any extra decode complexity. Is it because the current arrangement leaves the most room for the largest instructions? Is the encoding space not as problematic?