When in Swift 3 compatibility mode without
`-warn-swift3-objc-inference`, warn on the *uses* of declarations that
depend on the Objective-C runtime that became `@objc` due to the
deprecated inference rule. This far more directly captures important
uses of the deprecated Objective-C entrypoints. We diagnose:
* `#selector` expressions that refer to one of these `@objc` members
* `#keyPath` expressions that refer to one of these `@objc` members
* Dynamic lookup (i.e., member access via `AnyObject`) that refers to
one of these `@objc` members.
If this had a default, it should be the effective language version,
not the compiler language version. That is, in the Swift 4 compiler's
Swift 3 mode, we want to be acting like Swift 3, not Swift 4.
Store leading a trailing "trivia" around a token, such as whitespace,
comments, doc comments, and escaping backticks. These are syntactically
important for preserving formatting when printing ASTs but don't
semantically affect the program.
Tokens take all trailing trivia up to, but not including, the next
newline. This is important to maintain checks that statements without
semicolon separators start on a new line, among other things.
Trivia are now data attached to the ends of tokens, not tokens
themselves.
Create a new Syntax sublibrary for upcoming immutable, persistent,
thread-safe ASTs, which will contain only the syntactic information
about source structure, as well as for generating new source code, and
structural editing. Proactively move swift::Token into there.
Since this patch is getting a bit large, a token fuzzer which checks
for round-trip equivlence with the workflow:
fuzzer => token stream => file1
=> Lexer => token stream => file 2 => diff(file1, file2)
Will arrive in a subsequent commit.
This patch does not change the grammar.
UnconditionalAvailabilityKind => PlatformAgnosticAvailabilityKind
::UnavailableInCurrentSwift => ::SwiftVersionSpecific
Plus a couple related method renamings. Prep work for SR-2709.
One minor revision: this lifts the proposed restriction against
overriding a non-open method with an open one. On reflection,
that was inconsistent with the existing rule permitting non-public
methods to be overridden with public ones. The restriction on
subclassing a non-open class with an open class remains, and is
in fact consistent with the existing access rule.
What I've implemented here deviates from the current proposal text
in the following ways:
- I had to introduce a FunctionArrowPrecedence to capture the parsing
of -> in expression contexts.
- I found it convenient to continue to model the assignment property
explicitly.
- The comparison and casting operators have historically been
non-associative; I have chosen to preserve that, since I don't
think this proposal intended to change it.
- This uses the precedence group names and higherThan/lowerThan
as agreed in discussion.
A given Objective-C error enum, which is effectively an NS_ENUM that
specifies its corresponding error domain, will now be mapped to an
ErrorProtocol-conforming struct that wraps an NSError, much like
NSCocoaError does. The actual enum is mapped to a nested "Code"
enum. For example, CoreLocation's CLError becomes:
struct CLError : ErrorProtocol {
let _nsError: NSError
// ...
@objc enum Code : Int {
case ...
}
}
This implements bullet (2) in the proposed solution of SE-0112, so
that Cocoa error types are mapped into structures that maintain the
underlying NSError to allow more information to be extracted from it.
When attempting to compile Swift 2 code (or any Swift code using the
Swift 2 names) in Swift 3, the compiler diagnostics are often entirely
useless because the names have changed radically enough that one
generally gets "no member named 'foo'" errors rather than a helpful
"'foo' was renamed to 'bar'" error. This makes for a very poor user
experience when (e.g.) trying to move Swift 2 code forward to Swift 3.
To improve the experience, when the Swift 2 and Swift 3 names of an
API differ, the Clang importer will produce a "stub" declaration that
matches the Swift 2 API. That stub will be marked with a synthesized
attribute
@available(unavailable, renamed: "the-swift-3-name")
that enables better diagnostics (e.g., "'foo' is unavailable: renamed
to 'bar') along with Fix-Its (courtesy of @jrose-apple's recent work)
that fix the Swift 2 code to compile in Swift 3.
This change addresses much of rdar://problem/25309323 (concerning QoI
of Swift 2 code compiled with a Swift 3 compiler), but some cleanup
remains.
It should have the same form as the argument to NS_SWIFT_NAME
in Objective-C, except that it permits operators and (currently)
disallows instance members and properties. We do get to share the
same parsing code, at least.
This actually caught an error in the Foundation overlay!
Groundwork for SR-1008.
Previously it was not possible to parse expressions of the form
[Int -> Int]()
because no Expr could represent the '->' token and be converted later
into a FunctionTypeRepr. This commit introduces ArrowExpr which exists
solely to be converted to FunctionTypeRepr later by simplifyTypeExpr.
https://bugs.swift.org/browse/SR-502
This was mistakenly reverted in an attempt to fix buildbots.
Unfortunately it's now smashed into one commit.
---
Introduce @_specialize(<type list>) internal attribute.
This attribute can be attached to generic functions. The attribute's
arguments must be a list of concrete types to be substituted in the
function's generic signature. Any number of specializations may be
associated with a generic function.
This attribute provides a hint to the compiler. At -O, the compiler
will generate the specified specializations and emit calls to the
specialized code in the original generic function guarded by type
checks.
The current attribute is designed to be an internal tool for
performance experimentation. It does not affect the language or
API. This work may be extended in the future to add user-visible
attributes that do provide API guarantees and/or direct dispatch to
specialized code.
This attribute works on any generic function: a freestanding function
with generic type parameters, a nongeneric method declared in a
generic class, a generic method in a nongeneric class or a generic
method in a generic class. A function's generic signature is a
concatenation of the generic context and the function's own generic
type parameters.
e.g.
struct S<T> {
var x: T
@_specialize(Int, Float)
mutating func exchangeSecond<U>(u: U, _ t: T) -> (U, T) {
x = t
return (u, x)
}
}
// Substitutes: <T, U> with <Int, Float> producing:
// S<Int>::exchangeSecond<Float>(u: Float, t: Int) -> (Float, Int)
---
[SILOptimizer] Introduce an eager-specializer pass.
This pass finds generic functions with @_specialized attributes and
generates specialized code for the attribute's concrete types. It
inserts type checks and guarded dispatch at the beginning of the
generic function for each specialization. Since we don't currently
expose this attribute as API and don't specialize vtables and witness
tables yet, the only way to reach the specialized code is by calling
the generic function which performs the guarded dispatch.
In the future, we can build on this work in several ways:
- cross module dispatch directly to specialized code
- dynamic dispatch directly to specialized code
- automated specialization based on less specific hints
- partial specialization
- and so on...
I reorganized and refactored the optimizer's generic utilities to
support direct function specialization as opposed to apply
specialization.
Temporarily reverting @_specialize because stdlib unit tests are
failing on an internal branch during deserialization.
This reverts commit e2c43cfe14, reversing
changes made to 9078011f93.
This attribute can be attached to generic functions. The attribute's
arguments must be a list of concrete types to be substituted in the
function's generic signature. Any number of specializations may be
associated with a generic function.
This attribute provides a hint to the compiler. At -O, the compiler
will generate the specified specializations and emit calls to the
specialized code in the original generic function guarded by type
checks.
The current attribute is designed to be an internal tool for
performance experimentation. It does not affect the language or
API. This work may be extended in the future to add user-visible
attributes that do provide API guarantees and/or direct dispatch to
specialized code.
This attribute works on any generic function: a freestanding function
with generic type parameters, a nongeneric method declared in a
generic class, a generic method in a nongeneric class or a generic
method in a generic class. A function's generic signature is a
concatenation of the generic context and the function's own generic
type parameters.
e.g.
struct S<T> {
var x: T
@_specialize(Int, Float)
mutating func exchangeSecond<U>(u: U, _ t: T) -> (U, T) {
x = t
return (u, x)
}
}
// Substitutes: <T, U> with <Int, Float> producing:
// S<Int>::exchangeSecond<Float>(u: Float, t: Int) -> (Float, Int)
There's an immediate need for this in the core libs, and we have most of the necessary pieces on hand to make it easy to implement. This is an unpolished initial implementation, with the following limitations, among others:
- It doesn't support bridging error conventions,
- It relies on ObjC interop,
- It doesn't check for symbol name collisions,
- It has an underscored name with required symbol name `@cdecl("symbol_name")`, awaiting official bikeshed painting.
As a first foray into annotating attribute, add tags around attribute
names. For now, treat any decl-modifiers as keywords. We will also want
to wrap the whole attribute (including any parameters) into tags as
well, but that will require more work in the callback hanlding.
Also factor the attribute printing to handle any special cases early,
which will simplify wrapping attributes in tags, since we can then just
put the whole switch intside the pre/post callbacks.
rdar://problem/24292226
This reorganization allows adding attributes that refer to types.
I need this for a @_specialize attribute with a type list.
PrintOptions.h and other headers depend on these enums. But Attr.h
defines a lot of classes that almost never need to be included.
This class formalizes the common case of the "trailing allocation" idiom we use
frequently. I didn't spot any true bugs while making this change, but I did see
places where we were using the wrong pointer type or casting through void* for
no good reason. This will keep us honest.
I'll get to the other libraries soon.
Introduce a new attribute, swift3_migration, that lets us describe the
transformation required to map a Swift 2.x API into its Swift 3
equivalent. The only transformation understood now is "renamed" (to
some other declaration name), but there's a message field where we can
record information about other changes. The attribute can grow
somewhat (e.g., to represent parameter reordering) as we need it.
Right now, we do nothing but store and validate this attribute.
This is something that we have wanted for a long time and will enable us to
remove some hacks from the compiler (i.e. how we determine in the ARC optimizer
that we have "fatalError" like function) and also express new things like
"noarc".
This is not wired up to SIL yet so whichever is the first value will
take precedence. We already support multiple values at the SIL level, but at the
SIL level the last value takes precedence.
Per Doug's request I added an optional transform range templated on the
attribute. This will make it easy to get all attributes from the AST of a
specific kind.
This reflects the fact that the attribute's only for compiler-internal use, and isn't really equivalent to C's asm attribute, since it doesn't change the calling convention to be C-compatible.
This came out of today's language review meeting.
The intent is to match #available with the attribute
that describes availability.
This is a divergence from Objective-C.
Swift SVN r28484
Modules occupy a weird space in the AST now: they can be treated like
types (Swift.Int), which is captured by ModuleType. They can be
treated like values for disambiguation (Swift.print), which is
captured by ModuleExpr. And we jump through hoops in various places to
store "either a module or a decl".
Start cleaning this up by transforming Module into ModuleDecl, a
TypeDecl that's implicitly created to describe a module. Subsequent
changes will start folding away the special cases (ModuleExpr ->
DeclRefExpr, name lookup results stop having a separate Module case,
etc.).
Note that the Module -> ModuleDecl typedef is there to limit the
changes needed. Much of this patch is actually dealing with the fact
that Module used to have Ctx and Name public members that now need to
be accessed via getASTContext() and getName(), respectively.
Swift SVN r28284
Rather than swizzle the superclass of these bridging classes at +load time, have the compiler set their ObjC runtime base classes, using a "@_swift_native_objc_runtime_base" attribute that tells the compiler to use a different implicit base class from SwiftObject. This lets the runtime shed its last lingering +loads, and should overall be more robust, since it doesn't rely on static initialization order or deprecated ObjC runtime calls.
Swift SVN r28219
@warn_unused_result can be attached to function declarations to
produce a warning if the function is called but its result is not
used. It has two optional parameters that can be placed in
parentheses:
message="some message": a message to include with the warning.
mutable_variant="somedecl": the name of the mutable variant of the
method that should be suggested when the subject method is called on
a mutable value.
The specific use we're implementing this for now is for the mutating
and in-place operations. For example:
@warn_unused_result(mutable_variant="sortInPlace") func sort() -> [Generator.Element] { ... }
mutating func sortInPlace() { ... }
Translate Clang's __attribute__((warn_unused_result)) into
@warn_unused_result.
Implements rdar://problem/18165189.
Swift SVN r28019
