/// <summary>
/// Generates CIL for the addition operation.
/// </summary>
/// <param name="generator"> The generator to output the CIL to. </param>
/// <param name="optimizationInfo"> Information about any optimizations that should be performed. </param>
private void GenerateAdd(ILGenerator generator, OptimizationInfo optimizationInfo)
{
// Get the statically-determined types of the left and right operands.
Type leftType = this.Left.GetResultType(optimizationInfo);
Type rightType = this.Right.GetResultType(optimizationInfo);
// The add operator adds two strings together if at least one of the operands
// is a string, otherwise it adds two numbers.
if (PrimitiveTypeUtilities.IsString(leftType) || PrimitiveTypeUtilities.IsString(rightType))
{
// If at least one of the operands is a string, then the add operator concatenates.
// Load the left-hand side onto the stack.
this.Left.GenerateCode(generator, optimizationInfo);
// Convert the operand to a concatenated string.
EmitConversion.ToPrimitive(generator, leftType, PrimitiveTypeHint.None);
EmitConversion.ToConcatenatedString(generator, leftType);
// Load the right-hand side onto the stack.
this.Right.GenerateCode(generator, optimizationInfo);
if (rightType == typeof(string))
{
// Concatenate the two strings.
generator.Call(ReflectionHelpers.ConcatenatedString_Concatenate_String);
}
else if (rightType == typeof(ConcatenatedString))
{
// Concatenate the two strings.
generator.Call(ReflectionHelpers.ConcatenatedString_Concatenate_ConcatenatedString);
}
else
{
// Convert the operand to an object.
EmitConversion.ToPrimitive(generator, rightType, PrimitiveTypeHint.None);
EmitConversion.ToAny(generator, rightType);
// Concatenate the two strings.
generator.Call(ReflectionHelpers.ConcatenatedString_Concatenate_Object);
}
}
else if (leftType != typeof(object) && leftType != typeof(Library.ObjectInstance) &&
rightType != typeof(object) && rightType != typeof(Library.ObjectInstance))
{
// Neither of the operands are strings.
// If the two types are numeric integers, retain the one with the most accuracy.
Type numeric = TypeConverter.MostAccurateInteger(leftType, rightType);
if (numeric == null)
{
// Load the left hand side onto the stack.
this.Left.GenerateCode(generator, optimizationInfo);
// Convert the operand to a number.
EmitConversion.ToNumber(generator, leftType);
// Load the right hand side onto the stack.
this.Right.GenerateCode(generator, optimizationInfo);
// Convert the operand to a number.
EmitConversion.ToNumber(generator, rightType);
// Add the two numbers.
generator.Add();
}
else
{
// Use them both converted to 'numeric'
// Load the left hand side onto the stack.
this.Left.GenerateCode(generator, optimizationInfo);
// Convert the operand to a number.
EmitConversion.ToNumber(generator, leftType, numeric);
// Load the right hand side onto the stack.
this.Right.GenerateCode(generator, optimizationInfo);
// Convert the operand to a number.
EmitConversion.ToNumber(generator, rightType, numeric);
// Add the two numbers.
generator.Add();
}
}
else
{
// It is unknown whether the operands are strings.
// Load the left hand side onto the stack.
this.Left.GenerateCode(generator, optimizationInfo);
EmitConversion.ToAny(generator, leftType);
// Load the right hand side onto the stack.
this.Right.GenerateCode(generator, optimizationInfo);
EmitConversion.ToAny(generator, rightType);
// Add the two objects.
generator.Call(ReflectionHelpers.TypeUtilities_Add);
}
}
