Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
I was originally hoping to reuse mark_must_check for multiple types of checkers.
In practice, this is not what happened... so giving it a name specifically to do
with non copyable types makes more sense and makes the code clearer.
Just a pure rename.
llvm::SmallSetVector changed semantics
(https://reviews.llvm.org/D152497) resulting in build failures in Swift.
The old semantics allowed usage of types that did not have an
`operator==` because `SmallDenseSet` uses `DenseSetInfo<T>::isEqual` to
determine equality. The new implementation switched to using
`std::find`, which internally uses `operator==`. This type is used
pretty frequently with `swift::Type`, which intentionally deletes
`operator==` as it is not the canonical type and therefore cannot be
compared in normal circumstances.
This patch adds a new type-alias to the Swift namespace that provides
the old semantic behavior for `SmallSetVector`. I've also gone through
and replaced usages of `llvm::SmallSetVector` with the
`Swift::SmallSetVector` in places where we're storing a type that
doesn't implement or explicitly deletes `operator==`. The changes to
`llvm::SmallSetVector` should improve compile-time performance, so I
left the `llvm::SmallSetVector` where possible.
This is the first slice of bringing up escaping closure support. The support is
based around introducing a new type of SILGen VarLoc: a VarLoc with a box and
without a value. Because the VarLoc only has a box, we have to in SILGen always
eagerly reproject out the address from the box. The reason why I am doing this
is that it makes it easy for the move checker to distinguish in between
different accesses to the box that we want to check separately. As such every
time that we open the box, we insert a mark_must_check
[assignable_but_not_consumable] on that project. If allocbox_to_stack manages to
determine that the box can be stack allocated, we eliminate all of the
mark_must_check and place a new mark_must_check [consumable_and_assignable] on
the alloc_stack. The end result is that we get the old model that we had before
and also can support escaping closures.
Otherwise, sometimes when the object checker emits a diagnostic and cleans up
the IR, some of the cleaned up copies are copies that should have been handled
by the address checker. The end result is that the address checker does not emit
diagnostics for that IR. I found this problem was exascerbated when writing code
for escaping closures.
This commit also cleans up the passes in preparation for at a future time moving
some of the transformations into the utils folder.