public override void EmitGet(InstructionWriter writer, AllocatedLocal dest)
{
var leftStack = _leftStack ?? dest;
var rightStack = _rightStack ?? dest;
if (_left.GetSingleType() != _type || _right.GetSingleType() != _type)
{
//Needs conversion in MOV and ISTC.
throw new NotImplementedException();
}
if (leftStack.Offset > 255 || rightStack.Offset > 255 || dest.Offset > 255)
{
throw new NotImplementedException();
}
// emit leftStack = _left
// ISFC/ISTC dest, leftStack, exitLabel
// emit rightStack = _right
// MOV dest, rightStack
//exitLabel:
var exitLabel = new LabelStatementSyntaxNode();
_left.EmitPrep(writer);
_left.EmitGet(writer, leftStack);
writer.WriteUUS(_opcode, dest.Offset, leftStack.Offset, 0);
writer.AddLabelFix(exitLabel, InstructionWriter.FixUUSJump);
_right.EmitPrep(writer);
_right.EmitGet(writer, rightStack);
//We already wrote to dest. No need to MOV.
Debug.Assert(rightStack.Offset == dest.Offset);
writer.MarkLabel(exitLabel);
}
public override void Emit(InstructionWriter writer)
{
var restartLabel = new LabelStatementSyntaxNode();
var exitLabel = new LabelStatementSyntaxNode();
if (_e1Stack.Offset > 255 || _loopVar.Offset > 255)
{
throw new NotImplementedException();
}
//Calc expressions.
_e1.EmitPrep(writer);
_e1.EmitGet(writer, _e1Stack);
_e2.EmitPrep(writer);
_e2.EmitGet(writer, _e2Stack);
_e3.EmitPrep(writer);
_e3.EmitGet(writer, _e3Stack);
//Init instruction (check type, check exit condition).
writer.WriteUSx(_initOp, _e1Stack.Offset, 0);
writer.AddLabelFix(exitLabel, InstructionWriter.FixUSxJump);
//This is where we restart.
writer.MarkLabel(restartLabel);
//Start of the actual block (creates upvals).
_forBlock.EmitUpvalLists(writer);
//Copy hidden control variable to the visible loop var.
writer.WriteUUU(Opcodes.MOV, _loopVar.Offset, _e1Stack.Offset, 0);
//Emit inner aux block.
_forBlock.EmitStatements(writer);
//Loop instruction.
writer.WriteUSx(_loopOp, _e1Stack.Offset, 0);
writer.AddLabelFix(restartLabel, InstructionWriter.FixUSxJump);
writer.MarkLabel(exitLabel);
}
public override void EmitGet(InstructionWriter writer, AllocatedLocal dest)
{
//The two special cases.
if (_mode == CalcMode.LeftToDest)
{
if (_right.TryGetFromStack(out var rightStack) && rightStack.Offset == dest.Offset)
{
_left.EmitPrep(writer);
_left.EmitGet(writer, _rightTemp.Value);
EmitInstruction(writer, dest, _rightTemp.Value, rightStack);
return;
}
}
else if (_mode == CalcMode.RightToDest)
{
if (_left.TryGetFromStack(out var leftStack) && leftStack.Offset == dest.Offset)
{
_right.EmitPrep(writer);
_right.EmitGet(writer, _leftTemp.Value);
EmitInstruction(writer, dest, leftStack, _leftTemp.Value);
return;
}
}
switch (_mode)
{
case CalcMode.LeftToDest:
{
_left.EmitPrep(writer);
_left.EmitGet(writer, dest);
if (!_right.TryGetFromStack(out var rightStack))
{
rightStack = _rightTemp.Value;
_right.EmitPrep(writer);
_right.EmitGet(writer, rightStack);
}
EmitInstruction(writer, dest, dest, rightStack);
break;
}
case CalcMode.RightToDest:
{
if (!_left.TryGetFromStack(out var leftStack))
{
leftStack = _leftTemp.Value;
_left.EmitPrep(writer);
_left.EmitGet(writer, leftStack);
}
_right.EmitPrep(writer);
_right.EmitGet(writer, dest);
EmitInstruction(writer, dest, leftStack, dest);
break;
}
case CalcMode.Normal:
{
if (!_left.TryGetFromStack(out var leftStack))
{
leftStack = _leftTemp.Value;
_left.EmitPrep(writer);
_left.EmitGet(writer, leftStack);
}
if (!_right.TryGetFromStack(out var rightStack))
{
rightStack = _rightTemp.Value;
_right.EmitPrep(writer);
_right.EmitGet(writer, rightStack);
}
EmitInstruction(writer, dest, leftStack, rightStack);
break;
}
}
}
public override void Emit(InstructionWriter writer)
{
_expr.EmitPrep(writer);
_expr.EmitDiscard(writer);
}
