The translation of static fields now uses `VariableAddress` instead of `FieldAddress`. This fixes the logic as well as the "field address without qualifier address" sanity check.
Fixed a problem when the translating the compiler generated constructors that caused some sanity errors (since they have no body, when translating the constructor block fragmentation happened). Fixed this by skipping the translation of the body, if it does not exist (when translating a function).
This commit implements the language-neutral IR type system for C#. It mostly follows the same pattern as C++, modified to fit the C# type system. All object references, pointers, and lvalues are represented as `IRAddress` types. All structs and generic parameters are implemented as `IRBlobType`. Function addresses get a single `IRFunctionAddressType`.
I had to fix a couple places in the original IR type system where I didn't realize I was still depending on language-specific types. As part of this, `CSharpType` and `CppType` now have a `hasUnspecifiedType()` predicate, which is equivalent to `hasType()`, except that it holds only for the unspecified version of the type. This predicate can go away once we remove the IR's references to the underlying `Type` objects.
All C# IR tests pass without modification, but only because this commit continues to print the name of `IRUnknownType` as `null`, and `IRFunctionAddressType` as `glval<null>`. These will be fixed separately in a subsequent commit in this PR.
A constructed type, `C<T>`, where `T` is the type parameter of `C`, is represented
in the database as the corresponding unbound generict type `C<>`. Consequently, the
type conversion library, which only considers `ConstructedType`s, does not handle
all implicit conversions. For example, in
```
interface I<in T1, T2> where T1 : C
```
there should be an implicit conversion from `I<C, T2>` to `I<T1, T2>` (=`I<>`).
The translation of `IsExpr` created a sanity check to fail since it generated
a Phi node that had only one source: if a variable was declared as part of the `IsExpr`, a conditional branch was generated, and the variable was defined only in the true successor; this has been changes so that the declaration happens before the conditional branch, and the variable is uninitialized (this removed the need for the `isInitializedByElement` predicate from `TranslatedDeclarationBase`, so that has been removed) and only the assignment happens in the true successor block (so now the two inputs of the Phi node are the result of the `Uninitialized` instruction and the `Store` instruction from the true successor block).
More accurate type sizes using language specific predicates from `IRCSharpLanguage.qll`.
Added immediate operands for some `PointerX` (add, sub) instructions.
Some other minor consistency fixes.
Added support for pointers and pointer operations and made sure all loads are correct.
Added support for the unsafe stmt.
Added basic support for the fixed stmt (for now we ignore the pinning).
Fixed a bug where assignments of the form `Object obj1 = obj2` would not generate a load instruction for `obj2` (see `raw_ir.expected`).
Added an extra `Load` for object creations that involve structs. This is because the variable that represents the struct should hold the actual struct, not a reference to it.
Refactored the piece of code that decided if a particular expr needs a load instruction and improved the code sharing between `TranslatedExpr.qll` and `TranslatedElement.qll` by creating 2 predicates that tell if a certain expr does or does not need a load.
Added support for `in`, `out` and `ref` parameters.
In theory this bug could associated CaptureOutNodes with the wrong transitively called
callable. However, in practice I could not create a test case that revealed incorrect
behaviour. I've included one such test case in the commit.
I believe that the cause of this is that OutNode::getACall() is not actually used in the
data flow libraries. Instead, DataFlowDispatch::Cached::getAnOutNode is the predicate
which is used to associated OutNode's with DataFlowCall's in practice, and that is always
used in a context that correctly binds the runtime target of the call.
