Well, I think I’ve come up with a more than suitable solution for CocoNES’s CPU emulator. It will remain an Objective-C class to facilitate variable scope limiting and other object-oriented goodness, but will take an advantage of a low-level method of NSObject that will return a method implementation pointer, which is basically a pointer to the actual C function that a method is built on. When the CPU object is initialized it will create a C array of these pointers with the index of each instruction being the same as the opcode for that instruction, so I can do a simple opcodes[current_opcode](); to run the opcode.

The CPU object will have an instruction counter that is incremented with each cycle of an instruction; each instruction will contain a switch() block that will take it to the correct place in the execution, so I can synchronize the CPU and the PPU. Basically I’m trying to make it act like the real thing, where the state is held until the next clock pulse. Then I can do the cycle on both the PPU and CPU, and make sure the correct data is on the data and address buses for the next clock pulse.