public override IEnumerable <TmsCommand> Translate(Z80AssemblyParsing.Commands.UnconditionalReturnCommand returnCommand)
{
var stackOperand = new IndirectAutoIncrementTmsOperand(_extendedRegisterMap[Z80AssemblyParsing.ExtendedRegister.SP]);
var registerOperand = new RegisterTmsOperand(WorkspaceRegister.R11);
yield return(new MoveCommand(returnCommand, stackOperand, registerOperand));
yield return(new ReturnCommand(returnCommand));
}
public override IEnumerable <TmsCommand> Translate(ConditionalReturnCommand returnCommand)
{
var stackPointerOperand = new IndirectAutoIncrementTmsOperand(_extendedRegisterMap[Z80AssemblyParsing.ExtendedRegister.SP]);
var returnAddressRegister = new RegisterTmsOperand(WorkspaceRegister.R11);
if (returnCommand.ConditionOperand.Condition == Z80AssemblyParsing.JumpConditions.PO ||
returnCommand.ConditionOperand.Condition == Z80AssemblyParsing.JumpConditions.PE)
{
yield return(new UntranslateableComment(returnCommand, $"ret translations on PO or PE condition are not automated."));
yield return(new UntranslateableComment(returnCommand, "Z80 used a single flag for Parity and Overflow, TMS9900 used two flags."));
yield return(new UntranslateableComment(returnCommand, "A human must decide whether to use JNO or JOP."));
yield return(new UntranslateableComment(returnCommand, returnCommand.SourceText));
}
else if (_typesByCondition.ContainsKey(returnCommand.ConditionOperand.Condition))
{
var retLabel = _labelHighlighter.GetNextRtLabel();
yield return(GetInverseJumpCommand(returnCommand, retLabel));
yield return(new MoveCommand(returnCommand, stackPointerOperand, returnAddressRegister));
yield return(new ReturnCommand(returnCommand));
yield return(new BlankLineInTms(returnCommand)
{
Label = retLabel
});
}
else if (returnCommand.ConditionOperand.Condition == Z80AssemblyParsing.JumpConditions.M)
{
var retLabel1 = _labelHighlighter.GetNextRtLabel();
var retLabel2 = _labelHighlighter.GetNextRtLabel();
yield return(new JumpIfLessThanCommand(returnCommand, new LabeledAddressWithoutAtTmsOperand(retLabel1)));
yield return(new JumpCommand(returnCommand, new LabeledAddressWithoutAtTmsOperand(retLabel2)));
yield return(new BlankLineInTms(returnCommand)
{
Label = retLabel1
});
yield return(new MoveCommand(returnCommand, stackPointerOperand, returnAddressRegister));
yield return(new ReturnCommand(returnCommand));
yield return(new BlankLineInTms(returnCommand)
{
Label = retLabel2
});
}
}
public override IEnumerable <TmsCommand> Translate(Z80AssemblyParsing.Commands.PopCommand popCommand)
{
var stackPointerIndirect = new IndirectAutoIncrementTmsOperand(_extendedRegisterMap[Z80ExtendedRegister.SP]);
var destinationOperand = GetOperand(popCommand.Operand, false);
yield return(new MoveCommand(popCommand, stackPointerIndirect, destinationOperand));
if (MustSeparateRegisterPairs(popCommand.Operand, out var copyFromOperand1, out var copyToOperand1))
{
yield return(new MoveByteCommand(popCommand, copyFromOperand1, copyToOperand1));
}
}
