public void doOp(MIPSChip_Instance chip)
{
last = chip.getRegister(rd);
Int64 result = unchecked ((Int64)chip.getRegister(rs) * (Int64)chip.getRegister(rd));
chip.setRegister(rd, (UInt32)(result & 0x0000ffff));
}
/// <summary>
/// Adds contents of rs to signed 16bit value and store in rt. Trap if overflow is detected.
/// Also saves the state of rt before changing it so it may be undone.
/// </summary>
/// <param name="chip"></param>
public void doOp(MIPSChip_Instance chip)
{
lastRt = chip.getRegister(rt);
try {
UInt32 temp = (UInt32) checked ((Int32)chip.getRegister(rs) + (Int32)immediate);
chip.setRegister(rt, temp);
} catch (OverflowException) {
chip.interrupt();
}
}
/// <summary>
/// Adds contents of rs to contents of rt and store in rd. Trap if overflow is detected.
/// Also saves the state of rd before changing it so it may be undone.
/// </summary>
/// <param name="chip"></param>
public void doOp(MIPSChip_Instance chip)
{
this.lastRd = chip.getRegister(this.rd);
try {
UInt32 temp = (UInt32) checked ((Int32)chip.getRegister(rs) + (Int32)chip.getRegister(rt));
chip.setRegister(rd, temp);
} catch (OverflowException) {
chip.interrupt();
}
}
public void doOp(MIPSChip_Instance chip)
{
last = chip.getRegister(rd);
UInt32 temp = chip.getRegister(rt) | 0xffffff00;
if (temp < 0xffffff80)
{
temp &= 0x000000ff;
}
chip.setRegister(rd, temp);
}
public void doOp(MIPSChip_Instance chip)
{
this.last = chip.getRegister(rd);
int count = 32;
UInt32 value = chip.getRegister(rs);
for (int i = 31; i >= 0; i--)
{
if (value >> i == 1)
{
count = 31 - i;
break;
}
}
chip.setRegister(rd, (UInt32)count);
}
/// <summary>
/// Reverts changes made by setting the contents of rt to the saved value.
/// For this to work properly, doOp must have been called only once with the same chip specified here.
/// Cannot account for any changes made to registers done by any trap handlers resulting from an overflow.
/// </summary>
/// <param name="chip"></param>
public void undoOp(MIPSChip_Instance chip)
{
chip.setRegister(this.rt, this.lastRt);
}
public void undoOp(MIPSChip_Instance chip)
{
chip.setRegister(rd, last);
}
/// <summary>
/// Adds contents of rs to contents of rt and store in rd.
/// Also saves the state of rd before changing it so it may be undone.
/// </summary>
/// <param name="chip"></param>
public void doOp(MIPSChip_Instance chip)
{
this.lastRd = chip.getRegister(this.rd);
chip.setRegister(rd, unchecked (chip.getRegister(rs) + chip.getRegister(rt)));
}
/// <summary>
/// Adds contents of rs to 16bit value and store in rt. Does not do anything upon overflow.
/// Also saves the state of rt before changing it so it may be undone.
/// </summary>
/// <param name="chip"></param>
public void doOp(MIPSChip_Instance chip)
{
lastRt = chip.getRegister(rt);
chip.setRegister(rt, unchecked (chip.getRegister(rs) + (UInt32)immediate));
}