The 65816 has stack-relative addressing, and a relocatable direct page which can act as a sort of frame pointer, but it's still a far cry from being compiler-fr

The 65816 has stack-relative addressing, and a relocatable direct page which can act as a sort of frame pointer, but it's still a far cry from being compiler-friendly. Severe annoyances include the painful lack of registers, having 8 and 16 bit be a global mode switch instead of just specifying the size in the instruction, lack of a barrel shifter, and the near/far pointer distinction. There's a reason why there have never been successful ports of GCC or LLVM to that architecture, even out of tree.