---- This is a list of old tasks, just here for historical value ---- Open question: Create a toplevel block for anonymous methods? Anonymous Methods ----------------- Plan: * Resolve anonymous methods before. * Each time a Local matches, if the mode is `InAnonymous', flag the VariableInfo for `proxying'. * During Resolve track the depth required for local variables. * Before Emit, create proxy classes with proper depth. * Emit. Notes on memory allocation -------------------------- Outdated: A run of the AllocationProfile shows that the compiler allocates roughly 30 megabytes of strings. From those, 20 megabytes come from LookupType. See the notes on current_container problems below on memory usage. LookupTypeReflection: --------------------- With something like `System.Object', LookupTypeReflection will be called twice: once to find out that `System' is not a type and once for System.Object. This is required because System.Reflection requires that the type/nested types are not separated by a dot but by a plus sign. A nested class would be My+Class (My being the toplevel, Class the nested one). It is interesting to look at the most called lookups when bootstrapping MCS: 647 LTR: ArrayList 713 LTR: System.Globalization 822 LTR: System.Object+Expression 904 LTR: Mono.CSharp.ArrayList 976 LTR: System.Runtime.CompilerServices 999 LTR: Type 1118 LTR: System.Runtime 1208 LTR: Mono.CSharp.Type 1373 LTR: Mono.Languages 1599 LTR: System.Diagnostics 2036 LTR: System.Text 2302 LTR: System.Reflection.Emit 2515 LTR: System.Collections 4527 LTR: System.Reflection 22273 LTR: Mono.CSharp 24245 LTR: System 27005 LTR: Mono Analysis: The top 9 lookups are done for things which are not types. Mono.CSharp.Type happens to be a common lookup: the class Type used heavily in the compiler in the default namespace. RED FLAG: Then `Type' is looked up alone a lot of the time, this happens in parameter declarations and am not entirely sure that this is correct (FindType will pass to LookupInterfaceOrClass a the current_type.FullName, which for some reason is null!). This seems to be a problem with a lost piece of context during FindType. System.Object is also used a lot as a toplevel class, and we assume it will have children, we should just shortcut this. A cache: Adding a cache and adding a catch for `System.Object' to flag that it wont be the root of a hierarchy reduced the MCS bootstrap time from 10.22 seconds to 8.90 seconds. This cache is currently enabled with SIMPLE_SPEEDUP in typemanager.cs. Memory consumption went down from 74 megs to 65 megs with this change. Major tasks: ------------ Pinned and volatile require type modifiers that can not be encoded with Reflection.Emit. * Revisit Primary-expression, as it has now been split into non-array-creation-expression and array-creation-expression. * Emit `pinned' for pinned local variables. Both `modreq' and pinned will require special hacks in the compiler. * Make sure that we are pinning the right variable * local_variable_declaration Not sure that this grammar is correct, we might have to resolve this during semantic analysis. * Optimizations In Indexers and Properties, probably support an EmitWithDup That emits the code to call Get and then leaves a this pointer in the stack, so that later a Store can be emitted using that this pointer (consider Property++ or Indexer++) * Use of local temporary in UnaryMutator We should get rid of the Localtemporary there for some cases This turns out to be very complex, at least for the post-version, because this case: a = i++ To produce optimal code, it is necessary for UnaryMutator to know that it is being assigned to a variable (the way the stack is laid out using dup requires the store to happen inside UnaryMutator). * Interface indexers I have not figured out why the Microsoft version puts an `instance' attribute, and I am not generating this `instance' attribute. Explanation: The reason for the `instance' attribute on indexers is that indexers only apply to instances * Check for Final when overriding, if the parent is Final, then we cant allow an override. Implement base indexer access. current_container/current_namespace and the DeclSpace ----------------------------------------------------- We are storing fully qualified names in the DeclSpace instead of the node, this is because `current_namespace' (Namepsace) is not a DeclSpace like `current_container'. The reason for storing the full names today is this: namespace X { class Y { } } namespace A { class Y { } } The problem is that we only use the namespace stack to track the "prefix" for typecontainers, but they are not typecontainers themselves, so we have to use fully qualified names, because both A.X and A.Y would be entered in the toplevel type container. If we use the short names, there would be a name clash. To fix this problem, we have to make namespaces DeclSpaces. The full size, contrasted with the size that could be stored is: corlib: Size of strings held: 368901 Size of strings short: 147863 System: Size of strings held: 212677 Size of strings short: 97521 System.XML: Size of strings held: 128055 Size of strings short: 35782 System.Data: Size of strings held: 117896 Size of strings short: 36153 System.Web: Size of strings held: 194527 Size of strings short: 58064 System.Windows.Forms: Size of strings held: 220495 Size of strings short: 64923 The use of DottedName --------------------- We could probably use a different system to represent names, like this: class Name { string simplename; Name parent; } So `System.ComponentModel' becomes: x: (System, null) y: (ComponentModel, x) The problem is that we would still need to construct the name to pass to GetType. This has been now implemented, its called "QualifiedIdentifier" TODO: 1. Create a "partial" emit context for each TypeContainer.. 2. EmitContext should be partially constructed. No IL Generator. interface_type review. parameter_array, line 952: `note: must be a single dimension array type'. Validate this Instance idea ------------- It would be nice to have things that can be "instances" to have an EmitInstance method (this would default to nothing). The idea is to be able to use efficiently the instance data on stack manipulations, as opposed to the current scheme, where we basically have a few special cases. * `yield' is no longer a keyword, it only has special meaning before a return or break keywords. * Study side effects with assign * Study TemporaryStorage/LocalStorage -> Merge/rename