1. The change in StaticString's withUTF8Buffer is to store the UTF-8 code unit properly in the buffer.
2. The change in StringCore's _nthContiguous is to represent the UTF-16 data correctly when it contains the high byte.
We ran validation tests and foundation tests with the change on x86-64 and s390x. No new regression is observed.
This is another necessary step in introducing changes
for SE-0107: UnsafeRawPointer.
UnsafeRawPointer is great for bytewise pointer operations.
OpaquePointer goes away.
The _RawByte type goes away.
StringBuffer always binds memory to the correct CodeUnit
when allocating memory.
Before accessing the string, a dynamic element width check
allows us to assume the bound memory type.
Generic entry points like atomicCompareExchange no longer handle
both kinds of pointers. Normally that's good because you
should not be using generics in that case, just upcast
to raw pointer. However, with pointers-to-pointers
you can't do that.
We can express the same using the `isUniquelyReferencedNonObjC` API.
- Rename `isUniquelyReferencedNonObjC` to `isKnownUniquelyReferenced`.
- Cleanup `ManagedBufferPointer` by removing holdsUniqueOrPinnedReference` and
renaming `holdsUniqueReference` to `isUniqueReference`.
- No longer promise to return false from `isKnownUniquelyReferenced` for @objc
class instances.
SR-1962
rdar://21886410
We were using a precondition which crashes the program when invalid input is
provided. We want to provide a way to gracefully check and handle invalid input
or shutdown the program if necessary.
SR-1930
The defaults we were generating for Collection and
BidirectionalCollection didn't make any sense, because if you could do
that strideable arithmetic then you essentially had random access.
Instead we constrain the defaults to apply to RandomAccessCollection
where the Indices are a CountableRange.
Implements SE-0055: https://github.com/apple/swift-evolution/blob/master/proposals/0055-optional-unsafe-pointers.md
- Add NULL as an extra inhabitant of Builtin.RawPointer (currently
hardcoded to 0 rather than being target-dependent).
- Import non-object pointers as Optional/IUO when nullable/null_unspecified
(like everything else).
- Change the type checker's *-to-pointer conversions to handle a layer of
optional.
- Use 'AutoreleasingUnsafeMutablePointer<NSError?>?' as the type of error
parameters exported to Objective-C.
- Drop NilLiteralConvertible conformance for all pointer types.
- Update the standard library and then all the tests.
I've decided to leave this commit only updating existing tests; any new
tests will come in the following commits. (That may mean some additional
implementation work to follow.)
The other major piece that's missing here is migration. I'm hoping we get
a lot of that with Swift 1.1's work for optional object references, but
I still need to investigate.
This is a staging attribute that will eventually mean "fixed-contents"
for structs and "closed" for enums, as described in
docs/LibraryEvolution.rst.
This is pretty much the minimal set of types that must be fixed-layout,
because SILGen makes assumptions about their lowering.
If desired, some SILGen refactoring can allow some of these to be
resilient. For example, bridging value types could be made to work
with resilient types.
This is more or less a workaround for some optimizations (mainly ARC opt) to avoid performance degradation with the upcoming inliner changes
In some situations it makes a big difference for ARC opt if a function is inlined or not, althought this shouldn't be the case.
This commit is the result of auditing the following files:
* StringBuffer.swift
* StringCharacterView.swift
* StringCore.swift
* StringInterpolation.swift.gyb
* StringLegacy.swift
