Replace the stub implementation of invalidation with the proper
implementation. A ReadPathCache is added to each global so that it can
keep tracks of what target are associated to which read paths.
The copy of a TupleTree is potentially very expensive, so it was
disabled until now and only allowed via the explict method clone().
We have now decided to make TupleTree copiable.
This commit adds a copy-constructor and a copy-assignment, killing the
clone() method that was already unused and is now effectively useless.
The version of callOnPathSteps without an actual instance was completely
ignoring the upcasted type of `UpcastablePointer`s. We now fix this by
calling the right template specialization, which we choose by inspecting
the key of the `UpcastablePointer`.
Model classes are now described by a YAML document, which is used to
generate C++ headers containing classes and all the boilerplate
required for YAML serialization/deserialization, usage in
SortedVectors, etc. See the README in include/revng/Model for more
info.
Before this commit, it was only matched by types that satisfied the
constraint `IsUpcastablePointer`, which is too strict.
Now also types that match `UpcastablePointerLike` satisfy the
constraints for this concept.
Alessandro Di Federico