private void populateJTypeExecutors()
{
JTypeExecutors = new Dictionary <JumpType, Action <JTypeInstruction, IStateAccessor> >
{
{ JumpType.Jump, (x, StateAccessor) => {
var pc = StateAccessor.GetPc() & 0xFC000000;
pc |= x.Target << 2;
StateAccessor.SetPc(pc);
} },
{ JumpType.JumpAndLink, (x, StateAccessor) => {
StateAccessor.WriteRegister(31, StateAccessor.GetPc() + 4);
var pc = StateAccessor.GetPc() & 0xFC000000;
pc |= x.Target << 2;
StateAccessor.SetPc(pc);
} },
};
}
private void populateRTypeExecutors()
{
RTypeExecutors = new Dictionary <RTypeFunction, Action <RTypeInstruction, IStateAccessor> >
{
{ RTypeFunction.Add, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, (uint)(((int)StateAccessor.ReadRegister(r.Rs)) + (int)(StateAccessor.ReadRegister(r.Rt))));
} },
{ RTypeFunction.UnsignedAdd, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, StateAccessor.ReadRegister(r.Rs) + StateAccessor.ReadRegister(r.Rt));
} },
{ RTypeFunction.BitwiseAnd, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, StateAccessor.ReadRegister(r.Rs) & StateAccessor.ReadRegister(r.Rt));
} },
{ RTypeFunction.Break, (r, StateAccessor) => {
StateAccessor.SetEpc(StateAccessor.GetPc());
StateAccessor.SetPc(0x3c);
StateAccessor.Skip();
} },
{ RTypeFunction.Divide, (r, StateAccessor) => {
var dividend = (int)StateAccessor.ReadRegister(r.Rs);
var divisor = (int)StateAccessor.ReadRegister(r.Rt);
StateAccessor.SetHi((uint)(dividend % divisor));
StateAccessor.SetLo((uint)(dividend / divisor));
} },
{ RTypeFunction.UnsignedDivide, (r, StateAccessor) => {
var dividend = StateAccessor.ReadRegister(r.Rs);
var divisor = StateAccessor.ReadRegister(r.Rt);
StateAccessor.SetHi(dividend % divisor);
StateAccessor.SetLo(dividend / divisor);
} },
{ RTypeFunction.JumpAndLinkRegister, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, StateAccessor.GetPc() + 4);
StateAccessor.SetPc(StateAccessor.ReadRegister(r.Rs));
} },
{ RTypeFunction.JumpRegister, (r, StateAccessor) => {
StateAccessor.SetPc(StateAccessor.ReadRegister(r.Rs));
} },
{ RTypeFunction.MoveFromHi, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, StateAccessor.GetHi());
} },
{ RTypeFunction.MoveFromLo, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, StateAccessor.GetLo());
} },
{ RTypeFunction.MoveToHi, (r, StateAccessor) => {
StateAccessor.SetHi(StateAccessor.ReadRegister(r.Rs));
} },
{ RTypeFunction.MoveToLo, (r, StateAccessor) => {
StateAccessor.SetLo(StateAccessor.ReadRegister(r.Rs));
} },
{ RTypeFunction.Multiply, (r, StateAccessor) => {
var a = (long)(int)StateAccessor.ReadRegister(r.Rs);
var b = (long)(int)StateAccessor.ReadRegister(r.Rt);
long result = a * b;
StateAccessor.SetLo((uint)((int)result));
StateAccessor.SetHi((uint)(result >> 32));
} },
{ RTypeFunction.UnsignedMultiply, (r, StateAccessor) => {
var a = (ulong)StateAccessor.ReadRegister(r.Rs);
var b = (ulong)StateAccessor.ReadRegister(r.Rt);
var result = a * b;
StateAccessor.SetLo((uint)result);
StateAccessor.SetHi((uint)(result >> 32));
} },
{ RTypeFunction.BitwiseNor, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, ~(StateAccessor.ReadRegister(r.Rs) | StateAccessor.ReadRegister(r.Rt)));
} },
{ RTypeFunction.BitwiseOr, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, (StateAccessor.ReadRegister(r.Rs) | StateAccessor.ReadRegister(r.Rt)));
} },
{ RTypeFunction.ShiftLeftLogical, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rt);
var b = (int)r.Sa;
StateAccessor.WriteRegister(r.Rd, a << b);
} },
{ RTypeFunction.ShiftLeftLogicalVariable, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rt);
var b = (int)StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rd, a << b);
} },
{ RTypeFunction.SetOnLessThan, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rs);
var b = (int)StateAccessor.ReadRegister(r.Rt);
StateAccessor.WriteRegister(r.Rd, a < b ? 1u : 0u);
} },
{ RTypeFunction.UnsignedSetOnLessThan, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rs);
var b = StateAccessor.ReadRegister(r.Rt);
StateAccessor.WriteRegister(r.Rd, a < b ? 1u : 0u);
} },
{ RTypeFunction.ShiftRightArithmetic, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rt);
var b = (int)r.Sa;
StateAccessor.WriteRegister(r.Rd, (uint)(a >> b));
} },
{ RTypeFunction.ShiftRightArithmeticVariable, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rt);
var b = (int)StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rd, (uint)(a >> b));
} },
{ RTypeFunction.ShiftRightLogical, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rt);
var b = (int)r.Sa;
StateAccessor.WriteRegister(r.Rd, a >> b);
} },
{ RTypeFunction.ShiftRightLogicalVariable, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rt);
var b = (int)StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rd, a >> b);
} },
{ RTypeFunction.Subtract, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rs);
var b = (int)StateAccessor.ReadRegister(r.Rt);
StateAccessor.WriteRegister(r.Rd, (uint)(a - b));
} },
{ RTypeFunction.UnsignedSubtract, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rs);
var b = (int)StateAccessor.ReadRegister(r.Rt);
StateAccessor.WriteRegister(r.Rd, (uint)(a - b));
} },
{ RTypeFunction.Syscall, (r, StateAccessor) => {
StateAccessor.SetEpc(StateAccessor.GetPc());
StateAccessor.SetPc(0x3c);
StateAccessor.Skip();
} },
{ RTypeFunction.BitwiseExclusiveOr, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rd, (StateAccessor.ReadRegister(r.Rs) ^ StateAccessor.ReadRegister(r.Rt)));
} },
};
}
private void populateITypeExecutors()
{
ITypeExecutors = new Dictionary <Opcode, Action <ITypeInstruction, IStateAccessor> >
{
{ Opcode.AddImmediate, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, (uint)(a + ((short)r.Immediate)));
} },
{ Opcode.UnsignedAddImmediate, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, (uint)(a + (short)r.Immediate));
} },
{ Opcode.BitwiseAndImmediate, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, a & r.Immediate);
} },
{ Opcode.BranchOnEqual, (r, StateAccessor) => {
var rs = StateAccessor.ReadRegister(r.Rs);
var rt = StateAccessor.ReadRegister(r.Rt);
if (rs == rt)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
} },
{ Opcode.Branch, (r, StateAccessor) => {
var rs = (int)StateAccessor.ReadRegister(r.Rs);
var rt = r.Rt;
switch (rt)
{
case 0:
if (rs < 0)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
break;
case 1:
if (rs >= 0)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
break;
case 16:
StateAccessor.WriteRegister(31, StateAccessor.GetPc() + 4);
if (rs < 0)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
break;
case 17:
StateAccessor.WriteRegister(31, StateAccessor.GetPc() + 4);
if (rs >= 0)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
break;
default:
throw new InvalidOperationException(String.Format("Invalid Branch {0}", rt));
}
} },
{ Opcode.BranchOnGreaterThanZero, (r, StateAccessor) => {
var rs = (int)StateAccessor.ReadRegister(r.Rs);
var rt = StateAccessor.ReadRegister(r.Rt);
if (rs > 0)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
} },
{ Opcode.BranchOnLessThanOrEqualToZero, (r, StateAccessor) => {
var rs = (int)StateAccessor.ReadRegister(r.Rs);
var rt = StateAccessor.ReadRegister(r.Rt);
if (rs <= 0)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
} },
{ Opcode.BranchOnNotEqual, (r, StateAccessor) => {
var rs = StateAccessor.ReadRegister(r.Rs);
var rt = StateAccessor.ReadRegister(r.Rt);
if (rs != rt)
{
StateAccessor.SetPc((uint)(StateAccessor.GetPc() + (short)(r.Immediate << 2)));
}
} },
{ Opcode.LoadByte, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
byte dt;
StateAccessor.GetMemoryData(ptr, out dt);
var data = (uint)((int)((sbyte)(dt)));
StateAccessor.WriteRegister(r.Rt, data);
} },
{ Opcode.UnsignedLoadByte, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
byte dt;
StateAccessor.GetMemoryData(ptr, out dt);
var data = (uint)dt;
StateAccessor.WriteRegister(r.Rt, data);
} },
{ Opcode.LoadHalfword, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
UInt16 dt;
StateAccessor.GetMemoryData(ptr, out dt);
var data = (uint)((int)((short)DataConverterUInt16(dt)));
StateAccessor.WriteRegister(r.Rt, data);
} },
{ Opcode.UnsignedLoadHalfword, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
UInt16 dt;
StateAccessor.GetMemoryData(ptr, out dt);
var data = DataConverterUInt16(dt);
StateAccessor.WriteRegister(r.Rt, data);
} },
{ Opcode.LoadUpperImmediate, (r, StateAccessor) => {
StateAccessor.WriteRegister(r.Rt, r.Immediate << 16);
} },
{ Opcode.LoadWord, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
UInt32 data;
StateAccessor.GetMemoryData(ptr, out data);
data = DataConverterUInt32(data);
StateAccessor.WriteRegister(r.Rt, data);
} },
{ Opcode.BitwiseOrImmediate, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, a | r.Immediate);
} },
{ Opcode.StoreByte, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
var data = (byte)(StateAccessor.ReadRegister(r.Rt));
StateAccessor.SetMemoryData(ptr, data);
} },
{ Opcode.SetOnLessThanImmediate, (r, StateAccessor) => {
var a = (int)StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, a < (short)r.Immediate ? 1u : 0u);
} },
{ Opcode.UnsignedSetOnLessThanImmediate, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, a < r.Immediate ? 1u : 0u);
} },
{ Opcode.StoreHalfword, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
var dt = (ushort)StateAccessor.ReadRegister(r.Rt);
dt = DataConverterUInt16(dt);
StateAccessor.SetMemoryData(ptr, (ushort)dt);
} },
{ Opcode.StoreWord, (r, StateAccessor) => {
var ptr = (uint)(((short)r.Immediate) + (int)StateAccessor.ReadRegister(r.Rs));
var data = DataConverterUInt32(StateAccessor.ReadRegister(r.Rt));
StateAccessor.SetMemoryData(ptr, data);
} },
{ Opcode.BitwiseExclusiveOrImmediate, (r, StateAccessor) => {
var a = StateAccessor.ReadRegister(r.Rs);
StateAccessor.WriteRegister(r.Rt, a ^ r.Immediate);
} },
};
}