bool AdjustInitializerStack(List <ILExpression> initializerStack, List <ILExpression> getters, ILExpression argument, ILVariable v, bool isCollection, bool isValueType)
{
// Argument is of the form 'getter(getter(...(v)))'
// Unpack it into a list of getters:
getters.Clear();
while (argument.Code == ILCode.CallvirtGetter || argument.Code == ILCode.CallGetter || argument.Code == ILCode.Ldfld)
{
getters.Add(argument);
if (argument.Arguments.Count != 1)
{
return(false);
}
argument = argument.Arguments[0];
}
// Ensure that the final argument is 'v'
if (isValueType)
{
ILVariable loadedVar;
if (!(argument.Match(ILCode.Ldloca, out loadedVar) && loadedVar == v))
{
return(false);
}
}
else
{
if (!argument.MatchLdloc(v))
{
return(false);
}
}
// Now compare the getters with those that are currently active on the initializer stack:
int i;
for (i = 1; i <= Math.Min(getters.Count, initializerStack.Count - 1); i++)
{
ILExpression g1 = initializerStack[i].Arguments[0]; // getter stored in initializer
ILExpression g2 = getters[getters.Count - i]; // matching getter from argument
if (g1.Operand != g2.Operand)
{
// operands differ, so we abort the comparison
break;
}
}
// Remove all initializers from the stack that were not matched with one from the argument:
initializerStack.RemoveRange(i, initializerStack.Count - i);
// Now create new initializers for the remaining arguments:
for (; i <= getters.Count; i++)
{
ILExpression g = getters[getters.Count - i];
IMemberRef mr = g.Operand as IMemberRef;
TypeSig returnType;
if (mr == null || mr.IsField)
{
returnType = TypeAnalysis.GetFieldType((IField)mr);
}
else
{
returnType = TypeAnalysis.SubstituteTypeArgs(((IMethod)mr).MethodSig.GetRetType(), method: (IMethod)mr);
}
ILExpression nestedInitializer = new ILExpression(
IsCollectionType(returnType) ? ILCode.InitCollection : ILCode.InitObject,
null, g);
// add new initializer to its parent:
ILExpression parentInitializer = initializerStack[initializerStack.Count - 1];
if (parentInitializer.Code == ILCode.InitCollection)
{
// can't add children to collection initializer
if (parentInitializer.Arguments.Count == 1)
{
// convert empty collection initializer to object initializer
parentInitializer.Code = ILCode.InitObject;
}
else
{
return(false);
}
}
parentInitializer.Arguments.Add(nestedInitializer);
initializerStack.Add(nestedInitializer);
}
ILExpression lastInitializer = initializerStack[initializerStack.Count - 1];
if (isCollection)
{
return(lastInitializer.Code == ILCode.InitCollection);
}
else
{
if (lastInitializer.Code == ILCode.InitCollection)
{
if (lastInitializer.Arguments.Count == 1)
{
// convert empty collection initializer to object initializer
lastInitializer.Code = ILCode.InitObject;
return(true);
}
else
{
return(false);
}
}
else
{
return(true);
}
}
}
