Rewrite Atomic to be less heavy

EricRabil · Sep 1, 2022 · 0b35586 · 0b35586
1 parent bfc2b1b
commit 0b35586
Showing 1 changed file with 30 additions and 9 deletions.
diff --git a/Sources/Swexy/Utilities/Atomic.swift b/Sources/Swexy/Utilities/Atomic.swift
@@ -8,24 +8,45 @@
 import Foundation
 
 @propertyWrapper
-public class Atomic<T> {
-    private var _wrappedValue: T
+public enum Atomic<T> {
+    case atomic(innerValue: T, semaphore: DispatchSemaphore)
+
+    @usableFromInline typealias MemoryLayout = (T, DispatchSemaphore)
+
+    @usableFromInline var memoryLayout: MemoryLayout {
+        @_transparent get {
+            unsafeBitCast(self, to: MemoryLayout.self)
+        }
+    }
+
+    @_transparent @usableFromInline var semaphore: DispatchSemaphore {
+        memoryLayout.1
+    }
+
+    @usableFromInline var _wrappedValue: T {
+        @_transparent get {
+            memoryLayout.0
+        }
+        @_transparent set {
+            self = .atomic(innerValue: newValue, semaphore: semaphore)
+        }
+    }
 
-    private let semaphore = DispatchSemaphore(value: 1)
     public var wrappedValue: T {
-        _read {
+        @_transparent get {
             semaphore.wait()
-            yield _wrappedValue
+            let returnValue = _wrappedValue
             semaphore.signal()
+            return returnValue
         }
-        _modify {
+        @_transparent set {
             semaphore.wait()
-            yield &_wrappedValue
+            _wrappedValue = newValue
             semaphore.signal()
         }
     }
 
-    public init(wrappedValue: T) {
-        _wrappedValue = wrappedValue
+    @_transparent public init(wrappedValue: T) {
+        self = .atomic(innerValue: wrappedValue, semaphore: DispatchSemaphore(value: 1))
     }
 }