The first option is a flag that enables MPC601 (POWER) instructions for CPUs that are not MPC601.
This can be useful for the following reasons:
1) To produce results similar to classic Mac OS which emulates MPC601 instructions on CPUs that don't implement MPC601 instructions. This option is used to compare the risu traces produced in Mac OS 9 on a G3 or G4 with DPPC.
2) May increase performance in apps that use POWER instructions on emulated machines with CPUs that are not MPC601. It is not known if any such apps exist but there could be since Apple included MPC601 emulation in classic Mac OS.
I don't know if the compiler is smart enough to figure out that ((guest_va & 0xFFF) + sizeof(T)) > 0x1000) is always false when sizeof(T) == 1 so we'll add a check for sizeof(T) > 1.
Instructions that are 8 characters or longer (such as mtdbat3l) did not have a space between opcode and operand. Now there is always a space. The width of the opcode column is unchanged except for those opcodes that have 8 or more characters.
Use "logical" since the functions deal with multiple bits instead of a single boolean value and because the 601 manual calls them Logical Instructions.
Use "ppc" for the enums because logical_and is defined elsewhere and because the original DPPC code used these names for those functions.
So the debugger can show them during stepping.
The fmt_* functions now take a PPCDisasmContext instead of just the ctx->instr_str so that they can alter the context.
Some fmt_* functions have an alternate (e.g. fmt_twoop_in for fmt_twoop) to indicate a difference in input/output registers.
The mtsrin and mfsrin instructions use a register to indicate which sr register to use.
The string instructions may affect multiple registers but only the first is included in the list.
Removed some extra blank lines.
Fixes:
lscbx: Add r0 check.
mftb: Do simplified if the spr is illegal. Maybe should do illegal opcode instead?