* 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.
This tells the compiler that repeated calls to this function will always generate the same result, which allows the optimizer to coalesce multiple calls, hoist calls out of loops, and other such nice things.
rdar://problem/20690429
These functions don't accept local variable heap memory, although the names make it sound like they work on anything. When you try, they mistakenly identify such things as ObjC objects, call through to the equivalent objc_* function, and crash confusingly. This adds Object to the name of each one to make it more clear what they accept.
rdar://problem/37285743
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`.
By design, we don't want private or function-nested types to be accessible by mangled name, since they don't have stable identities, and they could inadvertently become ABI if someone serialized a mangled string and expected to deserialize it into a type. Fixes rdar://problem/39826794 .
The token contents doesn't really matter, but it can't start with a digit if it's going to show up in mangled names using identifier grammar. `s/0x/$/` for some 80s flair.
- 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
