public static IEnumerable <Operation> DevirtualizeRegisters(IReadOnlyList <Operation> code)
{
var ru = new RegisterUsage(code);
var replace = new Dictionary <int, Register.RegisterId>();
foreach (var id in ru.GetPrioritisedVirtualRegisters())
{
var n = ru.CanNotReplace(id);
var to = PrioritisedRegisters.First(r => !n.Contains(RegisterUsage.ToReg(r)));
replace[id] = to;
ru.Replace(id, RegisterUsage.ToReg(to));
}
Operand Replace(Operand op)
{
return(op switch
{
StubRegister stubRegister => new Register(replace[stubRegister.Number], stubRegister.Size),
Memory memory => new Memory(Replace(memory.Address), memory.Size),
Shift shift => new Shift(Replace(shift.Register) as AnyRegister, shift.Shft),
_ => op
});
}
public AnyRegister NewRegister(int size) => LastRegister = new StubRegister(_usedRegisters++, size);