private ushort Perform(ushort a, ushort b, Func <ushort, ushort, int> operation, RegisterFlags affectedFlags)
{
int intermediate = operation(a, b);
ushort result = (ushort)(intermediate & 0xFFFF);
_registers.ClearFlags(affectedFlags);
var setAffected = RegisterFlags.None;
if ((intermediate & (1 << 16)) == (1 << 16))
{
setAffected |= RegisterFlags.C;
}
if ((operation((ushort)(a & 0xFFF), (ushort)(b & 0xFFF)) & (1 << 12)) == (1 << 12))
{
setAffected |= RegisterFlags.H;
}
if (result == 0)
{
setAffected |= RegisterFlags.Z;
}
_registers.SetFlags(setAffected & affectedFlags);
return(result);
}
private ushort Perform(ushort a, ushort b, Func <ushort, ushort, int> operation, RegisterFlags affectedFlags)
{
int intermediate = operation(a, b);
ushort result = (ushort)(intermediate & 0xFFFF);
int carryBits = (a ^ b ^ intermediate);
int halfCarryBits = (a ^ b ^ result);
_registers.ClearFlags(affectedFlags);
var setAffected = RegisterFlags.None;
if ((carryBits & 0x10000) == 0x10000)
{
setAffected |= RegisterFlags.C;
}
if ((halfCarryBits & 0x1000) == 0x1000)
{
setAffected |= RegisterFlags.H;
}
if (result == 0)
{
setAffected |= RegisterFlags.Z;
}
_registers.SetFlags(setAffected & affectedFlags);
return(result);
}