private void EmitOptimizedPower(FleeILGenerator ilg, bool emitOverflow, bool unsigned)
{
Int32LiteralElement right = (Int32LiteralElement)MyRightChild;
if (right.Value == 0)
{
ilg.Emit(OpCodes.Pop);
IntegralLiteralElement.EmitLoad(1, ilg);
ImplicitConverter.EmitImplicitNumericConvert(typeof(Int32), MyLeftChild.ResultType, ilg);
return;
}
if (right.Value == 1)
{
return;
}
// Start at 1 since left operand has already been emited once
for (int i = 1; i <= right.Value - 1; i++)
{
ilg.Emit(OpCodes.Dup);
}
for (int i = 1; i <= right.Value - 1; i++)
{
this.EmitMultiply(ilg, emitOverflow, unsigned);
}
}
protected override System.Type GetResultType(System.Type leftType, System.Type rightType)
{
// Right argument (shift count) must be convertible to int32
if (ImplicitConverter.EmitImplicitNumericConvert(rightType, typeof(Int32), null) == false)
{
return(null);
}
// Left argument must be an integer type
if (Utility.IsIntegralType(leftType) == false)
{
return(null);
}
TypeCode tc = Type.GetTypeCode(leftType);
switch (tc)
{
case TypeCode.Byte:
case TypeCode.SByte:
case TypeCode.Int16:
case TypeCode.UInt16:
case TypeCode.Int32:
return(typeof(Int32));
case TypeCode.UInt32:
return(typeof(UInt32));
case TypeCode.Int64:
return(typeof(Int64));
case TypeCode.UInt64:
return(typeof(UInt64));
default:
Debug.Assert(false, "unknown left shift operand");
return(null);
}
}