| //===----------------------------------------------------------------------===// |
| // |
| // This source file is part of the Swift.org open source project |
| // |
| // Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors |
| // Licensed under Apache License v2.0 with Runtime Library Exception |
| // |
| // See http://swift.org/LICENSE.txt for license information |
| // See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors |
| // |
| //===----------------------------------------------------------------------===// |
| |
| import SwiftShims |
| |
| // Definitions that make elements of Builtin usable in real code |
| // without gobs of boilerplate. |
| |
| @available(*, unavailable, message: "use MemoryLayout<T>.size instead.") |
| public func sizeof<T>(_:T.Type) -> Int { |
| Builtin.unreachable() |
| } |
| |
| @available(*, unavailable, message: "use MemoryLayout<T>.size instead.") |
| public func sizeofValue<T>(_:T) -> Int { |
| Builtin.unreachable() |
| } |
| |
| @available(*, unavailable, message: "use MemoryLayout<T>.alignment instead.") |
| public func alignof<T>(_:T.Type) -> Int { |
| Builtin.unreachable() |
| } |
| |
| @available(*, unavailable, message: "use MemoryLayout<T>.alignment instead.") |
| public func alignofValue<T>(_:T) -> Int { |
| Builtin.unreachable() |
| } |
| |
| @available(*, unavailable, message: "use MemoryLayout<T>.stride instead.") |
| public func strideof<T>(_:T.Type) -> Int { |
| Builtin.unreachable() |
| } |
| |
| @available(*, unavailable, message: "use MemoryLayout<T>.stride instead.") |
| public func strideofValue<T>(_:T) -> Int { |
| Builtin.unreachable() |
| } |
| |
| // This function is the implementation of the `_roundUp` overload set. It is |
| // marked `@inline(__always)` to make primary `_roundUp` entry points seem |
| // cheap enough for the inliner. |
| @_versioned |
| @inline(__always) |
| internal func _roundUpImpl(_ offset: UInt, toAlignment alignment: Int) -> UInt { |
| _sanityCheck(alignment > 0) |
| _sanityCheck(_isPowerOf2(alignment)) |
| // Note, given that offset is >= 0, and alignment > 0, we don't |
| // need to underflow check the -1, as it can never underflow. |
| let x = offset + UInt(bitPattern: alignment) &- 1 |
| // Note, as alignment is a power of 2, we'll use masking to efficiently |
| // get the aligned value |
| return x & ~(UInt(bitPattern: alignment) &- 1) |
| } |
| |
| @_versioned |
| internal func _roundUp(_ offset: UInt, toAlignment alignment: Int) -> UInt { |
| return _roundUpImpl(offset, toAlignment: alignment) |
| } |
| |
| @_versioned |
| internal func _roundUp(_ offset: Int, toAlignment alignment: Int) -> Int { |
| _sanityCheck(offset >= 0) |
| return Int(_roundUpImpl(UInt(bitPattern: offset), toAlignment: alignment)) |
| } |
| |
| // This function takes a raw pointer and returns a typed pointer. It implicitly |
| // assumes that memory at the returned pointer is bound to `Destination` type. |
| @_versioned |
| internal func _roundUp<DestinationType>( |
| _ pointer: UnsafeMutableRawPointer, |
| toAlignmentOf destinationType: DestinationType.Type |
| ) -> UnsafeMutablePointer<DestinationType> { |
| // Note: unsafe unwrap is safe because this operation can only increase the |
| // value, and can not produce a null pointer. |
| return UnsafeMutablePointer<DestinationType>( |
| bitPattern: _roundUpImpl( |
| UInt(bitPattern: pointer), |
| toAlignment: MemoryLayout<DestinationType>.alignment) |
| ).unsafelyUnwrapped |
| } |
| |
| /// Returns a tri-state of 0 = no, 1 = yes, 2 = maybe. |
| @_transparent |
| public // @testable |
| func _canBeClass<T>(_: T.Type) -> Int8 { |
| return Int8(Builtin.canBeClass(T.self)) |
| } |
| |
| /// Returns the bits of `x`, interpreted as having type `U`. |
| /// |
| /// - Warning: Breaks the guarantees of Swift's type system; use |
| /// with extreme care. There's almost always a better way to do |
| /// anything. |
| /// |
| @_transparent |
| public func unsafeBitCast<T, U>(_ x: T, to: U.Type) -> U { |
| _precondition(MemoryLayout<T>.size == MemoryLayout<U>.size, |
| "can't unsafeBitCast between types of different sizes") |
| return Builtin.reinterpretCast(x) |
| } |
| |
| /// `unsafeBitCast` something to `AnyObject`. |
| @_transparent |
| internal func _reinterpretCastToAnyObject<T>(_ x: T) -> AnyObject { |
| return unsafeBitCast(x, to: AnyObject.self) |
| } |
| |
| @_transparent |
| func == (lhs: Builtin.NativeObject, rhs: Builtin.NativeObject) -> Bool { |
| return unsafeBitCast(lhs, to: Int.self) == unsafeBitCast(rhs, to: Int.self) |
| } |
| |
| @_transparent |
| func != (lhs: Builtin.NativeObject, rhs: Builtin.NativeObject) -> Bool { |
| return !(lhs == rhs) |
| } |
| |
| @_transparent |
| func == (lhs: Builtin.RawPointer, rhs: Builtin.RawPointer) -> Bool { |
| return unsafeBitCast(lhs, to: Int.self) == unsafeBitCast(rhs, to: Int.self) |
| } |
| |
| @_transparent |
| func != (lhs: Builtin.RawPointer, rhs: Builtin.RawPointer) -> Bool { |
| return !(lhs == rhs) |
| } |
| |
| /// Returns `true` iff `t0` is identical to `t1`; i.e. if they are both |
| /// `nil` or they both represent the same type. |
| public func == (t0: Any.Type?, t1: Any.Type?) -> Bool { |
| return unsafeBitCast(t0, to: Int.self) == unsafeBitCast(t1, to: Int.self) |
| } |
| |
| /// Returns `false` iff `t0` is identical to `t1`; i.e. if they are both |
| /// `nil` or they both represent the same type. |
| public func != (t0: Any.Type?, t1: Any.Type?) -> Bool { |
| return !(t0 == t1) |
| } |
| |
| |
| /// Tell the optimizer that this code is unreachable if condition is |
| /// known at compile-time to be true. If condition is false, or true |
| /// but not a compile-time constant, this call has no effect. |
| @_transparent |
| internal func _unreachable(_ condition: Bool = true) { |
| if condition { |
| // FIXME: use a parameterized version of Builtin.unreachable when |
| // <rdar://problem/16806232> is closed. |
| Builtin.unreachable() |
| } |
| } |
| |
| /// Tell the optimizer that this code is unreachable if this builtin is |
| /// reachable after constant folding build configuration builtins. |
| @_versioned @_transparent internal |
| func _conditionallyUnreachable() -> Never { |
| Builtin.conditionallyUnreachable() |
| } |
| |
| @_versioned |
| @_silgen_name("_swift_isClassOrObjCExistentialType") |
| func _swift_isClassOrObjCExistentialType<T>(_ x: T.Type) -> Bool |
| |
| /// Returns `true` iff `T` is a class type or an `@objc` existential such as |
| /// `AnyObject`. |
| @_versioned |
| @inline(__always) |
| internal func _isClassOrObjCExistential<T>(_ x: T.Type) -> Bool { |
| let tmp = _canBeClass(x) |
| |
| // Is not a class. |
| if tmp == 0 { |
| return false |
| // Is a class. |
| } else if tmp == 1 { |
| return true |
| } |
| |
| // Maybe a class. |
| return _swift_isClassOrObjCExistentialType(x) |
| } |
| |
| /// Returns an `UnsafePointer` to the storage used for `object`. There's |
| /// not much you can do with this other than use it to identify the |
| /// object. |
| @available(*, unavailable, message: "Removed in Swift 3. Use Unmanaged.passUnretained(x).toOpaque() instead.") |
| public func unsafeAddress(of object: AnyObject) -> UnsafePointer<Void> { |
| Builtin.unreachable() |
| } |
| |
| @available(*, unavailable, message: "Removed in Swift 3. Use Unmanaged.passUnretained(x).toOpaque() instead.") |
| public func unsafeAddressOf(_ object: AnyObject) -> UnsafePointer<Void> { |
| Builtin.unreachable() |
| } |
| |
| /// Converts a reference of type `T` to a reference of type `U` after |
| /// unwrapping one level of Optional. |
| /// |
| /// Unwrapped `T` and `U` must be convertible to AnyObject. They may |
| /// be either a class or a class protocol. Either T, U, or both may be |
| /// optional references. |
| @_transparent |
| public func _unsafeReferenceCast<T, U>(_ x: T, to: U.Type) -> U { |
| return Builtin.castReference(x) |
| } |
| |
| /// - returns: `x as T`. |
| /// |
| /// - Precondition: `x is T`. In particular, in -O builds, no test is |
| /// performed to ensure that `x` actually has dynamic type `T`. |
| /// |
| /// - Warning: Trades safety for performance. Use `unsafeDowncast` |
| /// only when `x as T` has proven to be a performance problem and you |
| /// are confident that, always, `x is T`. It is better than an |
| /// `unsafeBitCast` because it's more restrictive, and because |
| /// checking is still performed in debug builds. |
| @_transparent |
| public func unsafeDowncast<T : AnyObject>(_ x: AnyObject, to: T.Type) -> T { |
| _debugPrecondition(x is T, "invalid unsafeDowncast") |
| return Builtin.castReference(x) |
| } |
| |
| @inline(__always) |
| public func _getUnsafePointerToStoredProperties(_ x: AnyObject) |
| -> UnsafeMutableRawPointer { |
| let storedPropertyOffset = _roundUp( |
| MemoryLayout<_HeapObject>.size, |
| toAlignment: MemoryLayout<Optional<AnyObject>>.alignment) |
| return UnsafeMutableRawPointer(Builtin.bridgeToRawPointer(x)) + |
| storedPropertyOffset |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Branch hints |
| //===----------------------------------------------------------------------===// |
| |
| // Use @_semantics to indicate that the optimizer recognizes the |
| // semantics of these function calls. This won't be necessary with |
| // mandatory generic inlining. |
| |
| @_versioned |
| @_transparent |
| @_semantics("branchhint") |
| internal func _branchHint(_ actual: Bool, expected: Bool) -> Bool { |
| return Bool(Builtin.int_expect_Int1(actual._value, expected._value)) |
| } |
| |
| /// Optimizer hint that `x` is expected to be `true`. |
| @_transparent |
| @_semantics("fastpath") |
| public func _fastPath(_ x: Bool) -> Bool { |
| return _branchHint(x, expected: true) |
| } |
| |
| /// Optimizer hint that `x` is expected to be `false`. |
| @_transparent |
| @_semantics("slowpath") |
| public func _slowPath(_ x: Bool) -> Bool { |
| return _branchHint(x, expected: false) |
| } |
| |
| /// Optimizer hint that the code where this function is called is on the fast |
| /// path. |
| @_transparent |
| public func _onFastPath() { |
| Builtin.onFastPath() |
| } |
| |
| //===--- Runtime shim wrappers --------------------------------------------===// |
| |
| /// Returns `true` iff the class indicated by `theClass` uses native |
| /// Swift reference-counting. |
| #if _runtime(_ObjC) |
| // Declare it here instead of RuntimeShims.h, because we need to specify |
| // the type of argument to be AnyClass. This is currently not possible |
| // when using RuntimeShims.h |
| @_silgen_name("swift_objc_class_usesNativeSwiftReferenceCounting") |
| func _usesNativeSwiftReferenceCounting(_ theClass: AnyClass) -> Bool |
| #else |
| @_versioned |
| @inline(__always) |
| func _usesNativeSwiftReferenceCounting(_ theClass: AnyClass) -> Bool { |
| return true |
| } |
| #endif |
| |
| @_silgen_name("swift_class_getInstanceExtents") |
| func swift_class_getInstanceExtents(_ theClass: AnyClass) |
| -> (negative: UInt, positive: UInt) |
| |
| @_silgen_name("swift_objc_class_unknownGetInstanceExtents") |
| func swift_objc_class_unknownGetInstanceExtents(_ theClass: AnyClass) |
| -> (negative: UInt, positive: UInt) |
| |
| /// - Returns: |
| @inline(__always) |
| internal func _class_getInstancePositiveExtentSize(_ theClass: AnyClass) -> Int { |
| #if _runtime(_ObjC) |
| return Int(swift_objc_class_unknownGetInstanceExtents(theClass).positive) |
| #else |
| return Int(swift_class_getInstanceExtents(theClass).positive) |
| #endif |
| } |
| |
| //===--- Builtin.BridgeObject ---------------------------------------------===// |
| |
| #if arch(i386) || arch(arm) |
| @_versioned |
| internal var _objectPointerSpareBits: UInt { |
| @inline(__always) get { return 0x0000_0003 } |
| } |
| @_versioned |
| internal var _objectPointerIsObjCBit: UInt { |
| @inline(__always) get { return 0x0000_0002 } |
| } |
| @_versioned |
| internal var _objectPointerLowSpareBitShift: UInt { |
| @inline(__always) get { return 0 } |
| } |
| @_versioned |
| internal var _objCTaggedPointerBits: UInt { |
| @inline(__always) get { return 0 } |
| } |
| #elseif arch(x86_64) |
| @_versioned |
| internal var _objectPointerSpareBits: UInt { |
| @inline(__always) get { return 0x7F00_0000_0000_0006 } |
| } |
| @_versioned |
| internal var _objectPointerIsObjCBit: UInt { |
| @inline(__always) get { return 0x4000_0000_0000_0000 } |
| } |
| @_versioned |
| internal var _objectPointerLowSpareBitShift: UInt { |
| @inline(__always) get { return 1 } |
| } |
| @_versioned |
| internal var _objCTaggedPointerBits: UInt { |
| @inline(__always) get { return 0x8000_0000_0000_0001 } |
| } |
| #elseif arch(arm64) |
| @_versioned |
| internal var _objectPointerSpareBits: UInt { |
| @inline(__always) get { return 0x7F00_0000_0000_0007 } |
| } |
| @_versioned |
| internal var _objectPointerIsObjCBit: UInt { |
| @inline(__always) get { return 0x4000_0000_0000_0000 } |
| } |
| @_versioned |
| internal var _objectPointerLowSpareBitShift: UInt { |
| @inline(__always) get { return 0 } |
| } |
| @_versioned |
| internal var _objCTaggedPointerBits: UInt { |
| @inline(__always) get { return 0x8000_0000_0000_0000 } |
| } |
| #elseif arch(powerpc64) || arch(powerpc64le) |
| @_versioned |
| internal var _objectPointerSpareBits: UInt { |
| @inline(__always) get { return 0x0000_0000_0000_0007 } |
| } |
| @_versioned |
| internal var _objectPointerIsObjCBit: UInt { |
| @inline(__always) get { return 0x0000_0000_0000_0002 } |
| } |
| @_versioned |
| internal var _objectPointerLowSpareBitShift: UInt { |
| @inline(__always) get { return 0 } |
| } |
| @_versioned |
| internal var _objCTaggedPointerBits: UInt { |
| @inline(__always) get { return 0 } |
| } |
| #elseif arch(s390x) |
| internal var _objectPointerSpareBits: UInt { |
| @inline(__always) get { return 0x0000_0000_0000_0007 } |
| } |
| internal var _objectPointerIsObjCBit: UInt { |
| @inline(__always) get { return 0x0000_0000_0000_0002 } |
| } |
| internal var _objectPointerLowSpareBitShift: UInt { |
| @inline(__always) get { return 0 } |
| } |
| internal var _objCTaggedPointerBits: UInt { |
| @inline(__always) get { return 0 } |
| } |
| #endif |
| |
| /// Extract the raw bits of `x`. |
| @_versioned |
| @inline(__always) |
| internal func _bitPattern(_ x: Builtin.BridgeObject) -> UInt { |
| return UInt(Builtin.castBitPatternFromBridgeObject(x)) |
| } |
| |
| /// Extract the raw spare bits of `x`. |
| @_versioned |
| @inline(__always) |
| internal func _nonPointerBits(_ x: Builtin.BridgeObject) -> UInt { |
| return _bitPattern(x) & _objectPointerSpareBits |
| } |
| |
| @_versioned |
| @inline(__always) |
| internal func _isObjCTaggedPointer(_ x: AnyObject) -> Bool { |
| return (Builtin.reinterpretCast(x) & _objCTaggedPointerBits) != 0 |
| } |
| |
| /// Create a `BridgeObject` around the given `nativeObject` with the |
| /// given spare bits. |
| /// |
| /// Reference-counting and other operations on this |
| /// object will have access to the knowledge that it is native. |
| /// |
| /// - Precondition: `bits & _objectPointerIsObjCBit == 0`, |
| /// `bits & _objectPointerSpareBits == bits`. |
| @_versioned |
| @inline(__always) |
| internal func _makeNativeBridgeObject( |
| _ nativeObject: AnyObject, _ bits: UInt |
| ) -> Builtin.BridgeObject { |
| _sanityCheck( |
| (bits & _objectPointerIsObjCBit) == 0, |
| "BridgeObject is treated as non-native when ObjC bit is set" |
| ) |
| return _makeBridgeObject(nativeObject, bits) |
| } |
| |
| /// Create a `BridgeObject` around the given `objCObject`. |
| @inline(__always) |
| public // @testable |
| func _makeObjCBridgeObject( |
| _ objCObject: AnyObject |
| ) -> Builtin.BridgeObject { |
| return _makeBridgeObject( |
| objCObject, |
| _isObjCTaggedPointer(objCObject) ? 0 : _objectPointerIsObjCBit) |
| } |
| |
| /// Create a `BridgeObject` around the given `object` with the |
| /// given spare bits. |
| /// |
| /// - Precondition: |
| /// |
| /// 1. `bits & _objectPointerSpareBits == bits` |
| /// 2. if `object` is a tagged pointer, `bits == 0`. Otherwise, |
| /// `object` is either a native object, or `bits == |
| /// _objectPointerIsObjCBit`. |
| @_versioned |
| @inline(__always) |
| internal func _makeBridgeObject( |
| _ object: AnyObject, _ bits: UInt |
| ) -> Builtin.BridgeObject { |
| _sanityCheck(!_isObjCTaggedPointer(object) || bits == 0, |
| "Tagged pointers cannot be combined with bits") |
| |
| _sanityCheck( |
| _isObjCTaggedPointer(object) |
| || _usesNativeSwiftReferenceCounting(type(of: object)) |
| || bits == _objectPointerIsObjCBit, |
| "All spare bits must be set in non-native, non-tagged bridge objects" |
| ) |
| |
| _sanityCheck( |
| bits & _objectPointerSpareBits == bits, |
| "Can't store non-spare bits into Builtin.BridgeObject") |
| |
| return Builtin.castToBridgeObject( |
| object, bits._builtinWordValue |
| ) |
| } |
| |
| @_silgen_name("_swift_class_getSuperclass") |
| internal func _swift_class_getSuperclass(_ t: AnyClass) -> AnyClass? |
| |
| /// Returns the superclass of `t`, if any. The result is `nil` if `t` is |
| /// a root class or class protocol. |
| @inline(__always) |
| public // @testable |
| func _getSuperclass(_ t: AnyClass) -> AnyClass? { |
| return _swift_class_getSuperclass(t) |
| } |
| |
| /// Returns the superclass of `t`, if any. The result is `nil` if `t` is |
| /// not a class, is a root class, or is a class protocol. |
| @inline(__always) |
| public // @testable |
| func _getSuperclass(_ t: Any.Type) -> AnyClass? { |
| return (t as? AnyClass).flatMap { _getSuperclass($0) } |
| } |
| |
| //===--- Builtin.IsUnique -------------------------------------------------===// |
| // _isUnique functions must take an inout object because they rely on |
| // Builtin.isUnique which requires an inout reference to preserve |
| // source-level copies in the presence of ARC optimization. |
| // |
| // Taking an inout object makes sense for two additional reasons: |
| // |
| // 1. You should only call it when about to mutate the object. |
| // Doing so otherwise implies a race condition if the buffer is |
| // shared across threads. |
| // |
| // 2. When it is not an inout function, self is passed by |
| // value... thus bumping the reference count and disturbing the |
| // result we are trying to observe, Dr. Heisenberg! |
| // |
| // _isUnique and _isUniquePinned cannot be made public or the compiler |
| // will attempt to generate generic code for the transparent function |
| // and type checking will fail. |
| |
| /// Returns `true` if `object` is uniquely referenced. |
| @_versioned |
| @_transparent |
| internal func _isUnique<T>(_ object: inout T) -> Bool { |
| return Bool(Builtin.isUnique(&object)) |
| } |
| |
| /// Returns `true` if `object` is uniquely referenced or pinned. |
| @_versioned |
| @_transparent |
| internal func _isUniqueOrPinned<T>(_ object: inout T) -> Bool { |
| return Bool(Builtin.isUniqueOrPinned(&object)) |
| } |
| |
| /// Returns `true` if `object` is uniquely referenced. |
| /// This provides sanity checks on top of the Builtin. |
| @_transparent |
| public // @testable |
| func _isUnique_native<T>(_ object: inout T) -> Bool { |
| // This could be a bridge object, single payload enum, or plain old |
| // reference. Any case it's non pointer bits must be zero, so |
| // force cast it to BridgeObject and check the spare bits. |
| _sanityCheck( |
| (_bitPattern(Builtin.reinterpretCast(object)) & _objectPointerSpareBits) |
| == 0) |
| _sanityCheck(_usesNativeSwiftReferenceCounting( |
| type(of: Builtin.reinterpretCast(object) as AnyObject))) |
| return Bool(Builtin.isUnique_native(&object)) |
| } |
| |
| /// Returns `true` if `object` is uniquely referenced or pinned. |
| /// This provides sanity checks on top of the Builtin. |
| @_transparent |
| public // @testable |
| func _isUniqueOrPinned_native<T>(_ object: inout T) -> Bool { |
| // This could be a bridge object, single payload enum, or plain old |
| // reference. Any case it's non pointer bits must be zero. |
| _sanityCheck( |
| (_bitPattern(Builtin.reinterpretCast(object)) & _objectPointerSpareBits) |
| == 0) |
| _sanityCheck(_usesNativeSwiftReferenceCounting( |
| type(of: Builtin.reinterpretCast(object) as AnyObject))) |
| return Bool(Builtin.isUniqueOrPinned_native(&object)) |
| } |
| |
| /// Returns `true` if type is a POD type. A POD type is a type that does not |
| /// require any special handling on copying or destruction. |
| @_transparent |
| public // @testable |
| func _isPOD<T>(_ type: T.Type) -> Bool { |
| return Bool(Builtin.ispod(type)) |
| } |
| |
| /// Returns `true` if type is nominally an Optional type. |
| @_transparent |
| public // @testable |
| func _isOptional<T>(_ type: T.Type) -> Bool { |
| return Bool(Builtin.isOptional(type)) |
| } |
| |
| @available(*, unavailable, message: "Removed in Swift 3. Please use Optional.unsafelyUnwrapped instead.") |
| public func unsafeUnwrap<T>(_ nonEmpty: T?) -> T { |
| Builtin.unreachable() |
| } |
| |
| /// Extract an object reference from an Any known to contain an object. |
| internal func _unsafeDowncastToAnyObject(fromAny any: Any) -> AnyObject { |
| _sanityCheck(type(of: any) is AnyObject.Type |
| || type(of: any) is AnyObject.Protocol, |
| "Any expected to contain object reference") |
| // With a SIL instruction, we could more efficiently grab the object reference |
| // out of the Any's inline storage. |
| |
| // On Linux, bridging isn't supported, so this is a force cast. |
| #if _runtime(_ObjC) |
| return any as AnyObject |
| #else |
| return any as! AnyObject |
| #endif |
| } |