Drop support for Swifts 5.7-5.9

As usual, we support just the three latest Swift releases: 5.10, 6.0 and 6.1.

Also delete obsolete C atomics. Dropping Swifts <5.9 allows us to make ATOMICS_NATIVE_BUILTINS the unconditional default behavior.

Author: lorentey

CMakeLists.txt

@@ -31,10 +31,7 @@ set(ATOMICS_C_FLAGS)
 if(CMAKE_Swift_COMPILER_VERSION VERSION_GREATER_EQUAL 5.9)
   list(APPEND ATOMICS_SWIFT_FLAGS
     "-enable-experimental-feature BuiltinModule"
-    "-DATOMICS_NATIVE_BUILTINS"
-    "-Xcc" "-DATOMICS_NATIVE_BUILTINS=1")
-  list(APPEND ATOMICS_C_FLAGS
-    "-DATOMICS_NATIVE_BUILTINS=1")
+    )
 endif()
 
 add_subdirectory(Sources)

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.9
+// swift-tools-version:5.10
 //===----------------------------------------------------------------------===//
 //
 // This source file is part of the Swift.org open source project
@@ -18,10 +18,8 @@ var _swiftSettings: [SwiftSetting] = []
 
 // Enable the use of native Swift compiler builtins instead of C atomics.
 _cSettings += [
-  .define("ATOMICS_NATIVE_BUILTINS"),
 ]
 _swiftSettings += [
-  .define("ATOMICS_NATIVE_BUILTINS"),
   .enableExperimentalFeature("BuiltinModule")
 ]
 
@@ -48,7 +46,6 @@ let package = Package(
         "Conformances/IntegerConformances.swift.gyb",
         "Conformances/PointerConformances.swift.gyb",
         "Primitives/Primitives.native.swift.gyb",
-        "Primitives/Primitives.shims.swift.gyb",
         "Types/IntegerOperations.swift.gyb",
       ],
       cSettings: _cSettings,

[email protected]

@@ -17,7 +17,6 @@ add_library(Atomics
   "Types/autogenerated/IntegerOperations.swift"
   "Unmanaged extensions.swift"
   "Primitives/autogenerated/Primitives.native.swift"
-  "Primitives/autogenerated/Primitives.shims.swift"
   "Conformances/RawRepresentable.swift"
   "Conformances/OptionalRawRepresentable.swift"
   "Conformances/autogenerated/IntegerConformances.swift"

[email protected]

@@ -16,7 +16,6 @@
 }%
 ${autogenerated_warning()}
 
-#if ATOMICS_NATIVE_BUILTINS
 import Builtin
 
 extension Bool {
@@ -26,9 +25,6 @@ extension Bool {
     self = unsafeBitCast(builtin, to: Bool.self)
   }
 }
-#else
-import _AtomicsShims
-#endif
 
 extension Bool: AtomicValue {
   @frozen
@@ -43,25 +39,16 @@ extension Bool: AtomicValue {
 
     @_transparent @_alwaysEmitIntoClient
     public init(_ value: Bool) {
-#if ATOMICS_NATIVE_BUILTINS
       _storage = value._atomicRepresentation
-#else
-      _storage = _sa_prepare_Int8(value._atomicRepresentation)
-#endif
     }
 
     @_transparent @_alwaysEmitIntoClient
     public func dispose() -> Value {
-#if ATOMICS_NATIVE_BUILTINS
       return _storage._decodeBool
-#else
-      return _sa_dispose_Int8(_storage)._decodeBool
-#endif
     }
   }
 }
 
-#if ATOMICS_NATIVE_BUILTINS
 extension Bool {
   @_transparent @_alwaysEmitIntoClient
   internal var _atomicRepresentation: _AtomicInt8Storage {
@@ -76,21 +63,6 @@ extension _AtomicInt8Storage {
     (Int8(self._value) & 1) != 0
   }
 }
-#else
-extension Bool {
-  @_transparent @_alwaysEmitIntoClient
-  internal var _atomicRepresentation: Int8 {
-    self ? 1 : 0
-  }
-}
-
-extension Int8 {
-  @_transparent @_alwaysEmitIntoClient
-  internal var _decodeBool: Bool {
-    (self & 1) != 0
-  }
-}
-#endif
 
 extension UnsafeMutablePointer
 where Pointee == Bool.AtomicRepresentation {

Sources/Atomics/CMakeLists.txt

@@ -29,10 +29,6 @@
 }%
 ${autogenerated_warning()}
 
-#if !ATOMICS_NATIVE_BUILTINS
-import _AtomicsShims
-#endif
-
 % for (swiftType, storageType, shimType) in integerTypes:
 
 extension ${swiftType}: AtomicValue {
@@ -48,20 +44,12 @@ extension ${swiftType}: AtomicValue {
 
     @_transparent @_alwaysEmitIntoClient
     public init(_ value: Value) {
-#if ATOMICS_NATIVE_BUILTINS
       _storage = Self._encode(value)
-#else
-      _storage = _sa_prepare_${shimType}(Self._encode(value))
-#endif
     }
 
     @_transparent @_alwaysEmitIntoClient
     public func dispose() -> Value {
-#if ATOMICS_NATIVE_BUILTINS
       return Self._decode(_storage)
-#else
-      return Self._decode(_sa_dispose_${shimType}(_storage))
-#endif
     }
   }
 }
@@ -76,7 +64,6 @@ where Pointee == ${swiftType}.AtomicRepresentation {
   }
 }
 
-#if ATOMICS_NATIVE_BUILTINS
 extension ${swiftType}.AtomicRepresentation {
   @_transparent @_alwaysEmitIntoClient
   static func _decode(_ storage: _Storage) -> Value {
@@ -88,27 +75,6 @@ extension ${swiftType}.AtomicRepresentation {
     return _Storage(value._value)
   }
 }
-#else
-extension ${swiftType}.AtomicRepresentation {
-  @_transparent @_alwaysEmitIntoClient
-  static func _decode(_ v: ${shimType}) -> Value {
-% if swiftType == shimType:
-    return v
-% else:
-    return Value(v._value)
-% end
-  }
-
-  @_transparent @_alwaysEmitIntoClient
-  static func _encode(_ value: Value) -> ${shimType} {
-% if swiftType == shimType:
-    return value
-% else:
-    return ${shimType}(value._value)
-% end
-  }
-}
-#endif
 
 extension ${swiftType}.AtomicRepresentation: AtomicStorage {
   @_semantics("atomics.requires_constant_orderings")