private static void JumpOnPlusAction(
CpuRegister r, Word operand, CpuRegisterSet registerSet, Memory memory)
{
FlagRegister fr = registerSet.FR;
Boolean condition = (!fr.SF && !fr.ZF);
DoJump(condition, operand, registerSet.PR);
}
private static void DoOperation(
Alu.OperationMethod operationMethod, CpuRegister r, Word operand, FlagRegister fr, Memory memory)
{
Boolean overflowFlag;
r.Value = operationMethod(r.Value, operand, out overflowFlag);
fr.SetFlags(r, overflowFlag);
}
/// <summary>
/// <see cref="CpuRegisterSet"/> のインスタンスを初期化します。
/// </summary>
internal CpuRegisterSet()
{
m_generalRegisters = new GeneralRegisters();
m_stackPointer = new CpuRegister(RegisterDef.SP);
m_programRegister = new CpuRegister(RegisterDef.PR);
m_flagRegister = new FlagRegister();
Reset();
}
private static void DoShift(
Alu.ShiftMethod shiftMethod, CpuRegister r, Word operand, FlagRegister fr)
{
UInt16 lastShiftedOutBit;
r.Value = shiftMethod(r.Value, operand, out lastShiftedOutBit);
Boolean overflowFlag = (lastShiftedOutBit != 0);
fr.SetFlags(r, overflowFlag);
}
private static void DoCompare(
Alu.CompareMethod compareMethod, CpuRegister r, Word operand, FlagRegister fr)
{
Boolean signFlag;
Boolean zeroFlag;
compareMethod(r.Value, operand, out signFlag, out zeroFlag);
const Boolean OverflowFlag = false;
fr.SetFlags(OverflowFlag, signFlag, zeroFlag);
}
private static void DoLogic(
Alu.OperationMethod operationMethod, CpuRegister r, Word operand, FlagRegister fr, Memory memory)
{
Boolean notUsed;
r.Value = operationMethod(r.Value, operand, out notUsed);
const Boolean OverflowFlag = false;
fr.SetFlags(r, OverflowFlag);
}