private static void EmitSignExtend(ArmEmitterContext context, bool signed, int bits)
{
IOpCode32AluUx op = (IOpCode32AluUx)context.CurrOp;
Operand m = GetAluM(context);
Operand res;
if (op.RotateBits == 0)
{
res = m;
}
else
{
Operand rotate = Const(op.RotateBits);
res = context.RotateRight(m, rotate);
}
switch (bits)
{
case 8:
res = (signed) ? context.SignExtend8(OperandType.I32, res) : context.ZeroExtend8(OperandType.I32, res);
break;
case 16:
res = (signed) ? context.SignExtend16(OperandType.I32, res) : context.ZeroExtend16(OperandType.I32, res);
break;
}
if (op.Add)
{
res = context.Add(res, GetAluN(context));
}
EmitAluStore(context, res);
}
private static void EmitExtend16(ArmEmitterContext context, bool signed)
{
IOpCode32AluUx op = (IOpCode32AluUx)context.CurrOp;
Operand m = GetAluM(context);
Operand res;
if (op.RotateBits == 0)
{
res = m;
}
else
{
Operand rotate = Const(op.RotateBits);
res = context.RotateRight(m, rotate);
}
Operand low16, high16;
if (signed)
{
low16 = context.SignExtend8(OperandType.I32, res);
high16 = context.SignExtend8(OperandType.I32, context.ShiftRightUI(res, Const(16)));
}
else
{
low16 = context.ZeroExtend8(OperandType.I32, res);
high16 = context.ZeroExtend8(OperandType.I32, context.ShiftRightUI(res, Const(16)));
}
if (op.Add)
{
Operand n = GetAluN(context);
Operand lowAdd, highAdd;
if (signed)
{
lowAdd = context.SignExtend16(OperandType.I32, n);
highAdd = context.SignExtend16(OperandType.I32, context.ShiftRightUI(n, Const(16)));
}
else
{
lowAdd = context.ZeroExtend16(OperandType.I32, n);
highAdd = context.ZeroExtend16(OperandType.I32, context.ShiftRightUI(n, Const(16)));
}
low16 = context.Add(low16, lowAdd);
high16 = context.Add(high16, highAdd);
}
res = context.BitwiseOr(
context.ZeroExtend16(OperandType.I32, low16),
context.ShiftLeft(context.ZeroExtend16(OperandType.I32, high16), Const(16)));
EmitAluStore(context, res);
}