'x is P' works now, and this function isn't used anywhere except by a test that exercises it. Removing this also lets us remove a swath of otherwise unused helper static functions in the runtime.
Swift SVN r26618
After some more discussion with John, we decided that subclassing is the only realistic option, at least until we eventually are able to integrate with the OS. Switch things around to allocate Swift error boxes as an ObjC subclass that contains the error value instead of trying to game it as a CFError.
Swift SVN r26562
Add a 'mayTakeValue' function, which returns true if we're allowed to take the value from an existential container (assuming we own the existential container value). This is true for class and opaque existential containers, but not for boxed existentials, where multiple owners may share references to the boxed value. Also add a 'deinitExistentialContainer' function to do any cleanup that must happen after the value has been consumed out of an existential container. Fix up an off-by-one indirection level in the SwiftError implementations of the existing existential container methods.
Swift SVN r26561
These should all apply to any Darwin platform, and the current behaviour
was breaking cross-compilation.
Introduces a SWIFT_DARWIN_VARIANTS pattern, to be used as follows:
if(SWIFT_HOST_VARIANT MATCHES "${SWIFT_DARWIN_VARIANTS}")
Also fix one place where I checked the CMAKE_SYSTEM_NAME instead of the
host variant that I recently introduced. I haven't attempted to find
the rest of the places we're doing this though.
Swift SVN r26554
The string version of r26479. There's a lot of backstory and justification
there, so just read that commit message again. The one addition for String
is that global NSString constants are loaded as String as well, so that
also has to go through the bridging code even though there's no function
call involved.
Finishes rdar://problem/19734621.
Swift SVN r26510
Teach ExistentialTypeMetadata how to project out the value pointer, type metadata, and protocol witness table from ErrorType containers. NFC yet; the dynamic casting and reflection machinery needs further work to correctly handle ErrorType boxes.
Swift SVN r26509
Rename 'assignment' attribute of infix operators to 'mutating'. Add
'has_assignment' attribute, which results in an implicit declaration of
the assignment version of the same operator. Parse "func =foo"
declaration and "foo.=bar" expression. Validate some basic properties of
in-place methods.
Not yet implemented: automatic generation of wrapper for =foo() if foo()
is implemented, or vice versa; likewise for operators.
Swift SVN r26508
...and similar for NSDictionary and NSSet.
For APIs that don't have a reason to distinguish "empty" and "absent" cases,
we encourage standardizing on "empty" and marking the result as non-optional
(or in Objective-C, __nonnull). However, there are system APIs whose
implementations currently do return nil rather than an empty collection
instance. In these cases, we recommend /changing/ the API to return the
appropriate "empty" value instead.
However, this can cause problems for backwards-deployment: while the API is
truly non-optional on system vN, a program may encounter a nil return value
if run on system vN-1. Objective-C can generally deal with this (especially
if the only thing you do is ask for the count or try to iterate over the
collection) but Swift can't. Therefore, we've decided to "play nice" and
accept nil return values for the collection types (NSArray, NSDictionary,
and NSSet) and implicitly treat them as "empty" values if they are the
result of an imported function or method.
Note that the current implementation has a hole regarding subscript getters,
since we still make an AST-level thunk for these in the Clang importer.
We can probably get rid of those these days, but I didn't want to touch
them at this point. It seems unlikely that there will be a subscript that
(a) is for a collection type, and (b) mistakenly returned nil in the past
rather than an empty collection.
There's another hole where an ObjC client calls one of these mistakenly-nil-
returning methods and then immediately hands the result off by calling a
Swift method. However, we have to draw the line somewhere.
(We're actually going to do this for strings as well; coming soon.)
rdar://problem/19734621
Swift SVN r26479
We have an SPI between the Swift compiler and Foundation based on the
SWIFT_SDK_OVERLAY_FOUNDATION_EPOCH preprocessor macro that allows us to
request the new API. rdar://20270080 tracks removing it.
Swift SVN r26475
If an existential type for a special protocol (not a composition) is instantiated, carry the special protocol identifier from that protocol to the existential, allowing us to easily recognize existentials with unique runtime characteristics.
Swift SVN r26436
With this change we will devirtualize in trivial cases where mandatory
inlining has exposed opportunities due to substituting types, for
example substituting a struct type into a witness_method where we can
now easily determine exactly what method will be called.
This makes it possible to use @transparent on struct methods that are
dispatched via generic functions, resulting in the opportunity to emit
diagnostics for these methods as well as eliminate the overhead of the
indirect call.
I saw a handful of 10+% perf improvements at -Onone on our benchmarks.
In theory this should allow us to remove the overloads for ++/-- in
FixedPoint.swift.gyb without a performance penalty (and with the proper
overflow diagnostics), but unfortunately if we were to do so, we would
currently dispatch to functions that lack runtime overflow
checks (rdar://problem/20226526).
Swift SVN r26397