This will be used to help IRGen record protocol requirements
with resilient default implementations in protocol metadata.
To enable testing before all the Sema support is in place, this
patch adds SIL parser, printer and verifier support for default
witness tables.
For now, SILGen emits empty default witness tables for protocol
declarations in resilient modules, and IRGen ignores them when
emitting protocol metadata.
Correctly determine callee closeness for func/ops that include generics
as part of more complicated parameters, i.e. tuple or closure args
containing generics as elements or args/results. Still only handling
single archetypes.
Also added code to check generic substitutions already made in the callee
parameters, which further helps diagnosis.
- Implement emission of type references for nominal type field
reflection, using a small custom encoder resulting in packed
structs, not strings. This will let us embed 7-bit encoded
32-bit relative offsets directly in the structure (not yet
hooked in).
- Use the AST Mangler for encoding type references
Archetypes and internal references were complicating this before, so we
can take the opportunity to reuse this machinery and avoid unique code
and new ABI.
Next up: Tests for reading the reflection sections and converting the
demangle tree into a tree of type references.
Todo: For concrete types, serialize the types for associated types of
their conformances to bootstrap the typeref substitution process.
rdar://problem/15617914
This tweet: https://twitter.com/radexp/status/694561060230184960 pointed out
the sad truth that most people don't know that stmt-condition can contain
(including a fixit) when they try to use && instead of commas between clauses.
Before:
t.swift:4:16: error: #available may only be used as condition of an 'if', 'guard' or 'while' statement
if x == y && #available(iOS 9, *) { }
^
t.swift:5:27: error: expected '{' after 'if' condition
if #available(iOS 9, *) && x == y {}
^
t.swift:5:37: error: braced block of statements is an unused closure
if #available(iOS 9, *) && x == y {}
^
t.swift:5:37: error: expression resolves to an unused function
if #available(iOS 9, *) && x == y {}
^~
After:
t.swift:4:13: error: expected ',' joining parts of a multi-clause condition
if x == y && #available(iOS 9, *) { }
^~
,
t.swift:5:27: error: expected ',' joining parts of a multi-clause condition
if #available(iOS 9, *) && x == y {}
^~
,
This is the beginning of the extension of the availability model
introduced in Swift 2.0 to support two interesting things: inlineable
code and binary frameworks not tied to an OS. The former is critical
to having a stable standard library that isn't shipped with a client app.
(For more information on both of these, see docs/LibraryEvolution.rst.)
The existing availability model enforces that API is not used unless
the developer has already guaranteed its existence. We want to reuse
this logic for these new purposes. Additionally, certain queries about
the AST are dependent on this type of information as well, e.g. "can I
assume this enum will not grow any additional cases?" If the enum comes
from the module being compiled, the answer is usually "yes", but not if
the code asking the question may be inlined into another binary!
(This latter purpose is currently served by ResilienceExpansion down at
the SIL level; my goal is to replace ResilienceExpansion with
AvailabilityContext. It's a bit heavier but would also allow additional
optimization in the future.)
This commit does not change any logic; it only wraps existing uses of
VersionRange in AvailabilityContext if they're not strictly referring to
the OS version.
For a concrete type, members from its conforming protocols' extensions can be hard
to manually surface. In this commit, when printing Swift modules, we start to replicate these
extensions and synthesize them as if they are the concrete type's native extensions.
Credit to Doug for suggesting this practice.
This will be used to wean the SILParser off contextual types.
It is unfortunate that we now bloat each FunctionTypeRepr by
16 bytes to allow generic function types to be written down
in SIL. Perhaps we could use a different TypeRepr subclass
for function types in SIL mode.
This is the inverse of mapTypeIntoContext(). There were three
implementations of similar algorithms elsewhere, in Sema,
SIL type lowering, and some code in GenericParamList that is
only used by the SIL parser.
This new function will replace the first two, and the final one
will be refactored away.
This will let us combine the Sema and SIL logic for mapping
contextual types to interface types. Recursing into SILFunctionType
in this case is fine, since going from a contextual type to an
interface type should never change conventions.
Introduce Fix-Its to aid migration from selectors spelled as string
literals ("foo:bar:", which is deprecated), as well as from
construction of Selector instances from string literals
(Selector("foo:bar"), which is still acceptable but not recommended),
to the #selector syntax. Jump through some hoops to disambiguate
method references if there are overloads:
fixits.swift:51:7: warning: use of string literal for Objective-C
selectors is deprecated; use '#selector' instead
_ = "overloadedWithInt:" as Selector
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#selector(Bar.overloaded(_:) as (Bar) -> (Int) -> ())
In the cases where we cannot provide a Fix-It to a #selector
expression, we wrap the string literal in a Selector(...) construction
to suppress the deprecation warning. These are also easily searchable
in the code base.
This also means we're doing more validation of the string literals
that go into Selector, i.e., that they are well-formed selectors and
that we know about some method that is @objc and has that
selector. We'll warn if either is untrue.
This controls emission of field metadata for reflection, providing
the default decision. We might want to explore finer-grained
control per type, likely as a source code annotation.
-strip-field-names
Strip field names from nominal type metadata.
-strip-field-metadata
Strip all field metadata for nominal types. This also implies
-strip-field-names.
NFC yet.
When one spells a compound declaration name in the source (e.g.,
insertSubview(_:aboveSubview:), keep track of the locations of the
base name, parentheses, and argument labels.