* stdlib: replace recursion in _siftDown with iteration
Iterative approach removes recursion overhead. Therefore performance
of sorting will be improved
A Dictionary.removeValue(forKey:) benchmark regressed 35% because recent changes in this PR caused an _UnsafeBitMap member to not be inlined in its implementation. (This was probably triggered by moving a method from Dictionary._Variant to _NativeDictionary.)
Add @inline(__always) to _UnsafeBitMap members.
While we’re at it, make _UnsafeBitMap @usableFromInline. It’s only public for testing purposes.
This is primarily for documentation purposes, although the default implementation (based on an iterator) may not return the correct value for bridged dictionaries with exotic implementations.
- Inlinability audit
- Create a _NativeSet/_NativeDictionary directly, without extracting it from a Set/Dictionary
- Swap the final result with an empty collection.
- Nest native/cocoa index types under their corresponding struct
- Move *IndexRepresentation enums under the corresponding Index type, renamed to _Variant.
- Rename Index._value to Index._variant.
- Remove internal typealiases.
- Remove underscore prefix from enum case names.
- _nativeIndex => _asNative, _cocoaIndex => _asCocoa
- Audit inlinability.
- Rename variant enum types and move them into the corresponding struct:
_VariantSetBuffer => Set._Variant
_VariantDictionaryBuffer => Dictionary._Variant
I found the buffer suffix did not positively contribute to understanding these types. And the extra indirection of the typealiases wasn't exactly helpful, either.
- Remove internal typealiases that resolved to these.
On Windows, `__swift_stdlib_UNumericType` and `__swift_stdlib_UCharCategory` are imported as `Int32`s rather than `UInt32`. Change the constructors to use the type's inferred `RawValue` rather than always `UInt32`.
- Fix error in `last(where:)` example
- Improve MemoryLayout, UnsafePointer, and integer operator discussions
- Clean up ranges and random APIs
- Revisions to overflow operators and the SignedNumeric requirements
- Standardize on 'nonoptional' in remaining uses
_StringGuts shouldn't expose a subscript, implying efficient
access. Switch to the explicit code unit fetch method. Update tests
accordingly, and switch off of deprecated typealiases.
Add an isSmall query to Character so testing doesn't have to bake in
internal format. Clarify the purpose of the invalid UTF-16 backdoor
creation method.
Create a _StringRepresentation struct to standardize internal testing
on. Internalize much of _StringGuts, except for some SPI hacks, and
update tests to use _StringRepresentation.
Remove many of the implementations of obsoleted String functionality
by replacing it with unreachable. A few remain temporarily until the
Foundation overlay can be updated.
Also, update TestJSONEncoder.swift off of deprecated functionality.
