private bool ConvertRefTypeToValueType(CilExpression argument)
{
if (argument.ExpressionType.IsTypeOf("System", "Object"))
{
if (argument is CilInstructionExpression e &&
e.Instructions.Count == 1)
{
switch (e.Instructions[0].OpCode.Code)
{
case CilCode.Ldind_Ref:
// Load from pointer.
LdObj(e);
break;
case CilCode.Box:
// If argument is a box expression, then we can apply an optimisation; remove both
// box and unbox, and convert the embedded expression directly:
e.Arguments[0].ExpectedType = argument.ExpectedType;
argument.ReplaceWith(ConvertValueType(e.Arguments[0]).Remove());
return(true);
default:
// Argument is something else. We need to unbox.
UnboxAny(argument);
break;
}
}
else
{
UnboxAny(argument);
}
return(true);
}
private bool EnsureTypeSafety(CilExpression argument)
{
bool changed = false;
if (!_context.TypeHelper.IsAssignableTo(argument.ExpressionType, argument.ExpectedType))
{
if (!argument.ExpressionType.IsValueType && argument.ExpectedType.IsValueType)
{
// Reference type -> Value type.
if (argument.ExpressionType.IsTypeOf("System", "Object"))
{
if (argument is CilInstructionExpression e &&
e.Instructions.Count == 1 &&
e.Instructions[0].OpCode.Code == CilCode.Ldind_Ref)
{
LdObj(e);
}
else
{
UnboxAny(argument);
}
changed = true;
}
else if (argument.ExpressionType is PointerTypeSignature)
{
ConvertValueType(argument);
changed = true;
}
}
else if (!argument.ExpressionType.IsValueType && !argument.ExpectedType.IsValueType)
{
// Reference type -> Reference type.
CastClass(argument);
changed = true;
}
else if (argument.ExpressionType.IsValueType && !argument.ExpectedType.IsValueType)
{
// Value type -> Reference type.
var newArg = Box(argument);
if (!newArg.ExpectedType.IsTypeOf("System", "Object"))
{
CastClass(newArg);
}
changed = true;
}
else if (argument.ExpressionType.IsValueType && argument.ExpectedType.IsValueType)
{
// Value type -> Value type.
ConvertValueType(argument);
changed = true;
}
}
private bool IsBoxExpression(CilExpression expression, out CilExpression argument, out ITypeDefOrRef boxedType)
{
if (expression is CilInstructionExpression arg &&
arg.Instructions.Count == 1 &&
arg.Instructions[0].OpCode.Code == CilCode.Box)
{
argument = arg.Arguments[0];
boxedType = (ITypeDefOrRef)arg.Instructions[0].Operand;
return(true);
}
argument = null;
boxedType = null;
return(false);
}
private bool EnsureTypeSafety(CilExpression argument)
{
bool changed = false;
if (!_context.TypeHelper.IsAssignableTo(argument.ExpressionType, argument.ExpectedType))
{
if (!argument.ExpressionType.IsValueType && argument.ExpectedType.IsValueType)
{
// Reference type -> Value type.
changed = ConvertRefTypeToValueType(argument);
}
else if (!argument.ExpressionType.IsValueType && !argument.ExpectedType.IsValueType)
{
// Reference type -> Reference type.
CastClass(argument);
changed = true;
}
else if (argument.ExpressionType.IsValueType && !argument.ExpectedType.IsValueType)
{
// Value type -> Reference type.
var newArg = Box(argument);
if (!newArg.ExpectedType.IsTypeOf("System", "Object"))
{
CastClass(newArg);
}
changed = true;
}
else if (argument.ExpressionType.IsValueType && argument.ExpectedType.IsValueType)
{
// Value type -> Value type.
ConvertValueType(argument);
changed = true;
}
}
return(changed);
}
