Introduce ExtensionDecl::getExtendedNominal() to provide the nominal
type declaration that the extension declaration extends. Move most
of the existing callers of the callers to getExtendedType() over to
getExtendedNominal(), because they don’t need the full type information.
ExtensionDecl::getExtendedNominal() is itself not very interesting yet,
because it depends on getExtendedType().
The storage kind has been replaced with three separate "impl kinds",
one for each of the basic access kinds (read, write, and read/write).
This makes it far easier to mix-and-match implementations of different
accessors, as well as subtleties like implementing both a setter
and an independent read/write operation.
AccessStrategy has become a bit more explicit about how exactly the
access should be implemented. For example, the accessor-based kinds
now carry the exact accessor intended to be used. Also, I've shifted
responsibilities slightly between AccessStrategy and AccessSemantics
so that AccessSemantics::Ordinary can be used except in the sorts of
semantic-bypasses that accessor synthesis wants. This requires
knowing the correct DC of the access when computing the access strategy;
the upshot is that SILGenFunction now needs a DC.
Accessor synthesis has been reworked so that only the declarations are
built immediately; body synthesis can be safely delayed out of the main
decl-checking path. This caused a large number of ramifications,
especially for lazy properties, and greatly inflated the size of this
patch. That is... really regrettable. The impetus for changing this
was necessity: I needed to rework accessor synthesis to end its reliance
on distinctions like Stored vs. StoredWithTrivialAccessors, and those
fixes were exposing serious re-entrancy problems, and fixing that... well.
Breaking the fixes apart at this point would be a serious endeavor.
The non-deallocating destructor doesn't exists when dealloc can be overriden,
which means any class that inherits from a class defined in Objective-C. This
isn't necessarily all @objc classes, because of the
-disable-objc-attr-requires-foundation-module flag.
Fixes rdar://problem/40542246.
Sometimes, inconsistently, an accessor appears as a member of a parent
DeclContext, but other times it can seemingly only be accessed through the
storage decl. Instead of trying to conditionalise on this, just use the storage
decl as the canonical source, and ignore direct visits to accessors (i.e. the
membership route to ones that are members of other things).
Fixes rdar://problem/40476839.
We need to be looking at the linkage of the witness, but mangling the
requirement. Also, getGetter() gets the getter, not the setter (copy-paste
strikes again).
Fixes rdar://problem/40355657.
This is yet another waypoint on the path towards the final
generic-metadata design. The immediate goal is to make the
pattern a private implementation detail and to give the runtime
more visibility into the allocation and caching of generic types.
Emit protocol conformance descriptors as separate symbols, rather than
inlining them within the section for protocol conformance records. We
want separate symbols for protocol conformances both because it is easier
to make them variable-length (as required for conditional
conformances) and because we want to reference them from witness
tables (both of which are coming up).
Also, bail out before emitting any default argument generators in Swift 4
mode. This is NFC, because we already check the linkage of the SILDeclRef
and skip it if its not public. But adding the check explicitly here
serves as a reminder that this entire code block can be deleted if we
ever decide to kill off Swift 3 compatibility.
This has three principal advantages:
- It gives some additional type-safety when working
with known accessors.
- It makes it significantly easier to test whether a declaration
is an accessor and encourages the use of a common idiom.
- It saves a small amount of memory in both FuncDecl and its
serialized form.
It is only top-level globals in the main file that do not have
accessors, something like class Foo { static var x = 0 } has them no
matter where it is.
Fixes rdar://problem/32391290 .
