cfold.cs

C#编译器源代码。Micorsoft开放源代码

								((IntConstant) right).Value);

						return new IntConstant (res, left.Location);
					} else if (left is DecimalConstant) {
						decimal res;

						if (ec.ConstantCheckState)
							res = checked (((DecimalConstant) left).Value /
								((DecimalConstant) right).Value);
						else
							res = unchecked (((DecimalConstant) left).Value /
								((DecimalConstant) right).Value);

						return new DecimalConstant (res, left.Location);
					} else {
						throw new Exception ( "Unexepected division input: " + left);
					}
				} catch (OverflowException){
					Error_CompileTimeOverflow (loc);

				} catch (DivideByZeroException) {
					Report.Error (020, loc, "Division by constant zero");
				}
				
				break;
				
			case Binary.Operator.Modulus:
				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				try {
					if (left is DoubleConstant){
						double res;
						
						if (ec.ConstantCheckState)
							res = checked (((DoubleConstant) left).Value %
								       ((DoubleConstant) right).Value);
						else
							res = unchecked (((DoubleConstant) left).Value %
									 ((DoubleConstant) right).Value);
						
						return new DoubleConstant (res, left.Location);
					} else if (left is FloatConstant){
						float res;
						
						if (ec.ConstantCheckState)
							res = checked (((FloatConstant) left).Value %
								       ((FloatConstant) right).Value);
						else
							res = unchecked (((FloatConstant) left).Value %
									 ((FloatConstant) right).Value);
						
						return new FloatConstant (res, left.Location);
					} else if (left is ULongConstant){
						ulong res;
						
						if (ec.ConstantCheckState)
							res = checked (((ULongConstant) left).Value %
								       ((ULongConstant) right).Value);
						else
							res = unchecked (((ULongConstant) left).Value %
									 ((ULongConstant) right).Value);
						
						return new ULongConstant (res, left.Location);
					} else if (left is LongConstant){
						long res;
						
						if (ec.ConstantCheckState)
							res = checked (((LongConstant) left).Value %
								       ((LongConstant) right).Value);
						else
							res = unchecked (((LongConstant) left).Value %
									 ((LongConstant) right).Value);
						
						return new LongConstant (res, left.Location);
					} else if (left is UIntConstant){
						uint res;
						
						if (ec.ConstantCheckState)
							res = checked (((UIntConstant) left).Value %
								       ((UIntConstant) right).Value);
						else
							res = unchecked (((UIntConstant) left).Value %
									 ((UIntConstant) right).Value);
						
						return new UIntConstant (res, left.Location);
					} else if (left is IntConstant){
						int res;

						if (ec.ConstantCheckState)
							res = checked (((IntConstant) left).Value %
								       ((IntConstant) right).Value);
						else
							res = unchecked (((IntConstant) left).Value %
									 ((IntConstant) right).Value);

						return new IntConstant (res, left.Location);
					} else {
						throw new Exception ( "Unexepected modulus input: " + left);
					}
				} catch (DivideByZeroException){
					Report.Error (020, loc, "Division by constant zero");
				} catch (OverflowException){
					Error_CompileTimeOverflow (loc);
				}
				break;

				//
				// There is no overflow checking on left shift
				//
			case Binary.Operator.LeftShift:
				IntConstant ic = right.ToInt (loc);
				if (ic == null){
					Binary.Error_OperatorCannotBeApplied (loc, "<<", lt, rt);
					return null;
				}
				int lshift_val = ic.Value;

				IntConstant lic;
				if ((lic = left.ConvertToInt ()) != null)
					return new IntConstant (lic.Value << lshift_val, left.Location);

				UIntConstant luic;
				if ((luic = left.ConvertToUInt ()) != null)
					return new UIntConstant (luic.Value << lshift_val, left.Location);

				LongConstant llc;
				if ((llc = left.ConvertToLong ()) != null)
					return new LongConstant (llc.Value << lshift_val, left.Location);

				ULongConstant lulc;
				if ((lulc = left.ConvertToULong ()) != null)
					return new ULongConstant (lulc.Value << lshift_val, left.Location);

				Binary.Error_OperatorCannotBeApplied (loc, "<<", lt, rt);
				break;

				//
				// There is no overflow checking on right shift
				//
			case Binary.Operator.RightShift:
				IntConstant sic = right.ToInt (loc);
				if (sic == null){
					Binary.Error_OperatorCannotBeApplied (loc, ">>", lt, rt);
					return null;
				}
				int rshift_val = sic.Value;

				IntConstant ric;
				if ((ric = left.ConvertToInt ()) != null)
					return new IntConstant (ric.Value >> rshift_val, left.Location);

				UIntConstant ruic;
				if ((ruic = left.ConvertToUInt ()) != null)
					return new UIntConstant (ruic.Value >> rshift_val, left.Location);

				LongConstant rlc;
				if ((rlc = left.ConvertToLong ()) != null)
					return new LongConstant (rlc.Value >> rshift_val, left.Location);

				ULongConstant rulc;
				if ((rulc = left.ConvertToULong ()) != null)
					return new ULongConstant (rulc.Value >> rshift_val, left.Location);

				Binary.Error_OperatorCannotBeApplied (loc, ">>", lt, rt);
				break;

			case Binary.Operator.LogicalAnd:
				if (left is BoolConstant && right is BoolConstant){
					return new BoolConstant (
						((BoolConstant) left).Value &&
						((BoolConstant) right).Value, left.Location);
				}
				break;

			case Binary.Operator.LogicalOr:
				if (left is BoolConstant && right is BoolConstant){
					return new BoolConstant (
						((BoolConstant) left).Value ||
						((BoolConstant) right).Value, left.Location);
				}
				break;
				
			case Binary.Operator.Equality:
				if (left is BoolConstant && right is BoolConstant){
					return new BoolConstant (
						((BoolConstant) left).Value ==
						((BoolConstant) right).Value, left.Location);
				
				}
				if (left is NullLiteral){
					if (right is NullLiteral)
						return new BoolConstant (true, left.Location);
					else if (right is StringConstant)
						return new BoolConstant (
							((StringConstant) right).Value == null, left.Location);
				} else if (right is NullLiteral){
					if (left is NullLiteral)
						return new BoolConstant (true, left.Location);
					else if (left is StringConstant)
						return new BoolConstant (
							((StringConstant) left).Value == null, left.Location);
				}
				if (left is StringConstant && right is StringConstant){
					return new BoolConstant (
						((StringConstant) left).Value ==
						((StringConstant) right).Value, left.Location);
					
				}

				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				bool_res = false;
				if (left is DoubleConstant)
					bool_res = ((DoubleConstant) left).Value ==
						((DoubleConstant) right).Value;
				else if (left is FloatConstant)
					bool_res = ((FloatConstant) left).Value ==
						((FloatConstant) right).Value;
				else if (left is ULongConstant)
					bool_res = ((ULongConstant) left).Value ==
						((ULongConstant) right).Value;
				else if (left is LongConstant)
					bool_res = ((LongConstant) left).Value ==
						((LongConstant) right).Value;
				else if (left is UIntConstant)
					bool_res = ((UIntConstant) left).Value ==
						((UIntConstant) right).Value;
				else if (left is IntConstant)
					bool_res = ((IntConstant) left).Value ==
						((IntConstant) right).Value;
				else
					return null;

				return new BoolConstant (bool_res, left.Location);

			case Binary.Operator.Inequality:
				if (left is BoolConstant && right is BoolConstant){
					return new BoolConstant (
						((BoolConstant) left).Value !=
						((BoolConstant) right).Value, left.Location);
				}
				if (left is NullLiteral){
					if (right is NullLiteral)
						return new BoolConstant (false, left.Location);
					else if (right is StringConstant)
						return new BoolConstant (
							((StringConstant) right).Value != null, left.Location);
				} else if (right is NullLiteral){
					if (left is NullLiteral)
						return new BoolConstant (false, left.Location);
					else if (left is StringConstant)
						return new BoolConstant (
							((StringConstant) left).Value != null, left.Location);
				}
				if (left is StringConstant && right is StringConstant){
					return new BoolConstant (
						((StringConstant) left).Value !=
						((StringConstant) right).Value, left.Location);
					
				}
				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				bool_res = false;
				if (left is DoubleConstant)
					bool_res = ((DoubleConstant) left).Value !=
						((DoubleConstant) right).Value;
				else if (left is FloatConstant)
					bool_res = ((FloatConstant) left).Value !=
						((FloatConstant) right).Value;
				else if (left is ULongConstant)
					bool_res = ((ULongConstant) left).Value !=
						((ULongConstant) right).Value;
				else if (left is LongConstant)
					bool_res = ((LongConstant) left).Value !=
						((LongConstant) right).Value;
				else if (left is UIntConstant)
					bool_res = ((UIntConstant) left).Value !=
						((UIntConstant) right).Value;
				else if (left is IntConstant)
					bool_res = ((IntConstant) left).Value !=
						((IntConstant) right).Value;
				else
					return null;

				return new BoolConstant (bool_res, left.Location);

			case Binary.Operator.LessThan:
				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				bool_res = false;
				if (left is DoubleConstant)
					bool_res = ((DoubleConstant) left).Value <
						((DoubleConstant) right).Value;
				else if (left is FloatConstant)
					bool_res = ((FloatConstant) left).Value <
						((FloatConstant) right).Value;
				else if (left is ULongConstant)
					bool_res = ((ULongConstant) left).Value <
						((ULongConstant) right).Value;
				else if (left is LongConstant)
					bool_res = ((LongConstant) left).Value <
						((LongConstant) right).Value;
				else if (left is UIntConstant)
					bool_res = ((UIntConstant) left).Value <
						((UIntConstant) right).Value;
				else if (left is IntConstant)
					bool_res = ((IntConstant) left).Value <
						((IntConstant) right).Value;
				else
					return null;

				return new BoolConstant (bool_res, left.Location);
				
			case Binary.Operator.GreaterThan:
				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				bool_res = false;
				if (left is DoubleConstant)
					bool_res = ((DoubleConstant) left).Value >
						((DoubleConstant) right).Value;
				else if (left is FloatConstant)
					bool_res = ((FloatConstant) left).Value >
						((FloatConstant) right).Value;
				else if (left is ULongConstant)
					bool_res = ((ULongConstant) left).Value >
						((ULongConstant) right).Value;
				else if (left is LongConstant)
					bool_res = ((LongConstant) left).Value >
						((LongConstant) right).Value;
				else if (left is UIntConstant)
					bool_res = ((UIntConstant) left).Value >
						((UIntConstant) right).Value;
				else if (left is IntConstant)
					bool_res = ((IntConstant) left).Value >
						((IntConstant) right).Value;
				else
					return null;

				return new BoolConstant (bool_res, left.Location);

			case Binary.Operator.GreaterThanOrEqual:
				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				bool_res = false;
				if (left is DoubleConstant)
					bool_res = ((DoubleConstant) left).Value >=
						((DoubleConstant) right).Value;
				else if (left is FloatConstant)
					bool_res = ((FloatConstant) left).Value >=
						((FloatConstant) right).Value;
				else if (left is ULongConstant)
					bool_res = ((ULongConstant) left).Value >=
						((ULongConstant) right).Value;
				else if (left is LongConstant)
					bool_res = ((LongConstant) left).Value >=
						((LongConstant) right).Value;
				else if (left is UIntConstant)
					bool_res = ((UIntConstant) left).Value >=
						((UIntConstant) right).Value;
				else if (left is IntConstant)
					bool_res = ((IntConstant) left).Value >=
						((IntConstant) right).Value;
				else
					return null;

				return new BoolConstant (bool_res, left.Location);

			case Binary.Operator.LessThanOrEqual:
				DoConstantNumericPromotions (ec, oper, ref left, ref right, loc);
				if (left == null || right == null)
					return null;

				bool_res = false;
				if (left is DoubleConstant)
					bool_res = ((DoubleConstant) left).Value <=
						((DoubleConstant) right).Value;
				else if (left is FloatConstant)
					bool_res = ((FloatConstant) left).Value <=
						((FloatConstant) right).Value;
				else if (left is ULongConstant)
					bool_res = ((ULongConstant) left).Value <=
						((ULongConstant) right).Value;
				else if (left is LongConstant)
					bool_res = ((LongConstant) left).Value <=
						((LongConstant) right).Value;
				else if (left is UIntConstant)
					bool_res = ((UIntConstant) left).Value <=
						((UIntConstant) right).Value;
				else if (left is IntConstant)
					bool_res = ((IntConstant) left).Value <=
						((IntConstant) right).Value;
				else
					return null;

				return new BoolConstant (bool_res, left.Location);
			}
					
			return null;
		}
	}
}