Merge pull request #20159 from lorentey/bridgestorage-audit

[stdlib] ABI audit for _BridgeStorage

Author: lorentey

stdlib/public/core/ArrayBuffer.swift

@@ -49,11 +49,6 @@ internal struct _ArrayBuffer<Element> : _ArrayBufferProtocol {
     return _ArrayBuffer<U>(storage: _storage)
   }
 
-  /// The spare bits that are set when a native array needs deferred
-  /// element type checking.
-  @inlinable
-  internal var deferredTypeCheckMask: Int { return 1 }
-  
   /// Returns an `_ArrayBuffer<U>` containing the same elements,
   /// deferring checking each element's `U`-ness until it is accessed.
   ///
@@ -71,8 +66,7 @@ internal struct _ArrayBuffer<Element> : _ArrayBufferProtocol {
     // _sanityCheck(U.self is Element.Type)
 
     return _ArrayBuffer<U>(
-      storage: _ArrayBridgeStorage(
-        native: _native._storage, bits: deferredTypeCheckMask))
+      storage: _ArrayBridgeStorage(native: _native._storage, isFlagged: true))
   }
 
   @inlinable
@@ -109,7 +103,7 @@ extension _ArrayBuffer {
   @inlinable
   internal mutating func isUniquelyReferenced() -> Bool {
     if !_isClassOrObjCExistential(Element.self) {
-      return _storage.isUniquelyReferenced_native_noSpareBits()
+      return _storage.isUniquelyReferencedUnflaggedNative()
     }
 
     // This is a performance optimization. This code used to be:
@@ -532,7 +526,7 @@ extension _ArrayBuffer {
     if !_isClassOrObjCExistential(Element.self) {
       return true
     } else {
-      return _storage.isNativeWithClearedSpareBits(deferredTypeCheckMask)
+      return _storage.isUnflaggedNative
     }
   }
 
@@ -543,15 +537,15 @@ extension _ArrayBuffer {
   internal var _native: NativeBuffer {
     return NativeBuffer(
       _isClassOrObjCExistential(Element.self)
-      ? _storage.nativeInstance : _storage.nativeInstance_noSpareBits)
+      ? _storage.nativeInstance : _storage.unflaggedNativeInstance)
   }
 
   /// Fast access to the native representation.
   ///
   /// - Precondition: `_isNativeTypeChecked`.
   @inlinable
   internal var _nativeTypeChecked: NativeBuffer {
-    return NativeBuffer(_storage.nativeInstance_noSpareBits)
+    return NativeBuffer(_storage.unflaggedNativeInstance)
   }
 
   @inlinable

stdlib/public/core/BridgeStorage.swift

@@ -21,42 +21,45 @@
 import SwiftShims
 
 @_fixed_layout
-public // @testable
-struct _BridgeStorage<
-  NativeClass: AnyObject, ObjCClass: AnyObject
+@usableFromInline
+internal struct _BridgeStorage<
+  NativeClass: AnyObject,
+  ObjCClass: AnyObject
 > {
-  public // @testable
-  typealias Native = NativeClass
-  
-  public // @testable
-  typealias ObjC = ObjCClass
-  
-  @inlinable // FIXME(sil-serialize-all)
+  @usableFromInline
+  internal typealias Native = NativeClass
+
+  @usableFromInline
+  internal typealias ObjC = ObjCClass
+
+  // rawValue is passed inout to _isUnique.  Although its value
+  // is unchanged, it must appear mutable to the optimizer.
+  @usableFromInline
+  internal var rawValue: Builtin.BridgeObject
+
+  @inlinable
   @inline(__always)
-  public // @testable
-  init(native: Native, bits: Int) {
+  internal init(native: Native, isFlagged flag: Bool) {
+    // Note: Some platforms provide more than one spare bit, but the minimum is
+    // a single bit.
+
     _sanityCheck(_usesNativeSwiftReferenceCounting(NativeClass.self))
-    
-    // More bits are available on some platforms, but it's not portable
-    _sanityCheck(0...1 ~= bits,
-        "BridgeStorage can't store bits outside the range 0...1")
 
     rawValue = _makeNativeBridgeObject(
-      native, UInt(bits) << _objectPointerLowSpareBitShift)
+      native,
+      flag ? (1 as UInt) << _objectPointerLowSpareBitShift : 0)
   }
-  
-  @inlinable // FIXME(sil-serialize-all)
+
+  @inlinable
   @inline(__always)
-  public // @testable
-  init(objC: ObjC) {
+  internal init(objC: ObjC) {
     _sanityCheck(_usesNativeSwiftReferenceCounting(NativeClass.self))
     rawValue = _makeObjCBridgeObject(objC)
   }
-  
-  @inlinable // FIXME(sil-serialize-all)
+
+  @inlinable
   @inline(__always)
-  public // @testable
-  init(native: Native) {
+  internal init(native: Native) {
     _sanityCheck(_usesNativeSwiftReferenceCounting(NativeClass.self))
     rawValue = Builtin.reinterpretCast(native)
   }
@@ -69,97 +72,73 @@ struct _BridgeStorage<
   }
 #endif
 
-  @inlinable // FIXME(sil-serialize-all)
-  public // @testable
-  var spareBits: Int {
-  @inline(__always) get {
-    _sanityCheck(isNative)
-    return Int(
-      _nonPointerBits(rawValue) >> _objectPointerLowSpareBitShift)
-    }
-  }
-  
-  @inlinable // FIXME(sil-serialize-all)
+  @inlinable
   @inline(__always)
-  public // @testable
-  mutating func isUniquelyReferencedNative() -> Bool {
+  internal mutating func isUniquelyReferencedNative() -> Bool {
     return _isUnique(&rawValue)
   }
 
-  @inlinable // FIXME(sil-serialize-all)
-  public // @testable
-  var isNative: Bool {
+  @inlinable
+  internal var isNative: Bool {
     @inline(__always) get {
       let result = Builtin.classifyBridgeObject(rawValue)
       return !Bool(Builtin.or_Int1(result.isObjCObject,
                                    result.isObjCTaggedPointer))
     }
   }
-  
-  @inlinable // FIXME(sil-serialize-all)
-  @inline(__always)
-  public // @testable
-  func isNativeWithClearedSpareBits(_ bits: Int) -> Bool {
-    return (_bitPattern(rawValue) &
-            (_bridgeObjectTaggedPointerBits | _objCTaggedPointerBits |
-             _objectPointerIsObjCBit |
-             (UInt(bits)) << _objectPointerLowSpareBitShift)) == 0
+
+  @inlinable
+  static var flagMask: UInt {
+    @inline(__always) get {
+      return (1 as UInt) << _objectPointerLowSpareBitShift
+    }
+  }
+
+  @inlinable
+  internal var isUnflaggedNative: Bool {
+    @inline(__always) get {
+      return (_bitPattern(rawValue) &
+        (_bridgeObjectTaggedPointerBits | _objCTaggedPointerBits |
+          _objectPointerIsObjCBit | _BridgeStorage.flagMask)) == 0
+    }
   }
 
-  @inlinable // FIXME(sil-serialize-all)
-  public // @testable
-  var isObjC: Bool {
+  @inlinable
+  internal var isObjC: Bool {
     @inline(__always) get {
       return !isNative
     }
   }
-  
-  @inlinable // FIXME(sil-serialize-all)
-  public // @testable
-  var nativeInstance: Native {
+
+  @inlinable
+  internal var nativeInstance: Native {
     @inline(__always) get {
       _sanityCheck(isNative)
       return Builtin.castReferenceFromBridgeObject(rawValue)
     }
   }
-  
-  @inlinable // FIXME(sil-serialize-all)
-  public // @testable
-  var nativeInstance_noSpareBits: Native {
+
+  @inlinable
+  internal var unflaggedNativeInstance: Native {
     @inline(__always) get {
       _sanityCheck(isNative)
       _sanityCheck(_nonPointerBits(rawValue) == 0)
       return Builtin.reinterpretCast(rawValue)
     }
   }
-  
-  @inlinable // FIXME(sil-serialize-all)
+
+  @inlinable
   @inline(__always)
-  public // @testable
-  mutating func isUniquelyReferenced_native_noSpareBits() -> Bool {
+  internal mutating func isUniquelyReferencedUnflaggedNative() -> Bool {
     _sanityCheck(isNative)
     return _isUnique_native(&rawValue)
   }
 
-  @inlinable // FIXME(sil-serialize-all)
-  public // @testable
-  var objCInstance: ObjC {
+  @inlinable
+  internal var objCInstance: ObjC {
     @inline(__always) get {
       _sanityCheck(isObjC)
       return Builtin.castReferenceFromBridgeObject(rawValue)
     }
   }
-  
-  //===--- private --------------------------------------------------------===//
-  @inlinable // FIXME(sil-serialize-all)
-  internal var _isTagged: Bool {
-    @inline(__always) get {
-      return Bool(Builtin.classifyBridgeObject(rawValue).isObjCTaggedPointer)
-    }
-  }
-
-  // rawValue is passed inout to _isUnique.  Although its value
-  // is unchanged, it must appear mutable to the optimizer.
-  @usableFromInline
-  internal var rawValue: Builtin.BridgeObject
 }

stdlib/public/core/DictionaryVariant.swift

@@ -78,28 +78,27 @@ extension Dictionary._Variant {
 
   @inlinable
   internal mutating func isUniquelyReferenced() -> Bool {
-    return object.isUniquelyReferenced_native_noSpareBits()
+    return object.isUniquelyReferencedUnflaggedNative()
   }
 
 #if _runtime(_ObjC)
   @usableFromInline @_transparent
   internal var isNative: Bool {
     if guaranteedNative { return true }
-    return object.isNativeWithClearedSpareBits(0)
+    return object.isUnflaggedNative
   }
 #endif
 
   @usableFromInline @_transparent
   internal var asNative: _NativeDictionary<Key, Value> {
     get {
-      return _NativeDictionary<Key, Value>(object.nativeInstance_noSpareBits)
+      return _NativeDictionary<Key, Value>(object.unflaggedNativeInstance)
     }
     set {
       self = .init(native: newValue)
     }
     _modify {
-      var native = _NativeDictionary<Key, Value>(
-        object.nativeInstance_noSpareBits)
+      var native = _NativeDictionary<Key, Value>(object.unflaggedNativeInstance)
       self = .init(dummy: ())
       yield &native
       object = .init(native: native._storage)

stdlib/public/core/SetVariant.swift

@@ -75,27 +75,27 @@ extension Set._Variant {
 
   @inlinable
   internal mutating func isUniquelyReferenced() -> Bool {
-    return object.isUniquelyReferenced_native_noSpareBits()
+    return object.isUniquelyReferencedUnflaggedNative()
   }
 
 #if _runtime(_ObjC)
   @usableFromInline @_transparent
   internal var isNative: Bool {
     if guaranteedNative { return true }
-    return object.isNativeWithClearedSpareBits(0)
+    return object.isUnflaggedNative
   }
 #endif
 
   @usableFromInline @_transparent
   internal var asNative: _NativeSet<Element> {
     get {
-      return _NativeSet(object.nativeInstance_noSpareBits)
+      return _NativeSet(object.unflaggedNativeInstance)
     }
     set {
       self = .init(native: newValue)
     }
     _modify {
-      var native = _NativeSet<Element>(object.nativeInstance_noSpareBits)
+      var native = _NativeSet<Element>(object.unflaggedNativeInstance)
       self = .init(dummy: ())
       yield &native
       object = .init(native: native._storage)

test/api-digester/Outputs/stability-stdlib-abi.swift.expected

@@ -8,8 +8,11 @@ Constructor AnyHashable.init(_box:) has been removed
 Constructor AnyHashable.init(_usingDefaultRepresentationOf:) has been removed
 Constructor ManagedBufferPointer.init(_:_:_:) has been removed
 Constructor Zip2Sequence.init(_sequence1:_sequence2:) has been removed
+Constructor _BridgeStorage.init(native:bits:) has been removed
 Constructor _BridgeableMetatype.init(value:) has been removed
 Func AnyHashable._downCastConditional(into:) has been removed
+Func _BridgeStorage.isNativeWithClearedSpareBits(_:) has been removed
+Func _BridgeStorage.isUniquelyReferenced_native_noSpareBits() has been removed
 Func _CocoaDictionary.Index.copy() has been removed
 Func _ContiguousArrayStorage._getNonVerbatimBridgedHeapBuffer() has been removed
 Func _ContiguousArrayStorage._withVerbatimBridgedUnsafeBufferImpl(_:) has been removed
@@ -28,6 +31,10 @@ Var ManagedBufferPointer.baseAddress has been removed
 Var ManagedBufferPointer.storage has been removed
 Var ManagedBufferPointer.value has been removed
 Var Optional._nilSentinel has been removed
+Var _ArrayBuffer.deferredTypeCheckMask has been removed
+Var _BridgeStorage._isTagged has been removed
+Var _BridgeStorage.nativeInstance_noSpareBits has been removed
+Var _BridgeStorage.spareBits has been removed
 Var _BridgeableMetatype.value has been removed
 Var _CocoaDictionary.Index._object has been removed
 Var _CocoaSet.Index._object has been removed