Add platform executor module for FreeBSD

Effectively the same as Linux and OpenBSD. If Dispatch is disabled, this
will fail because the dispatch executor isn't defined.

Author: etcwilde

Runtimes/Core/Concurrency/CMakeLists.txt

@@ -81,6 +81,7 @@ add_library(swift_Concurrency
   PartialAsyncTask.swift
   PlatformExecutorDarwin.swift
   PlatformExecutorLinux.swift
+  PlatformExecutorFreeBSD.swift
   PlatformExecutorOpenBSD.swift
   PlatformExecutorWindows.swift
   PriorityQueue.swift

stdlib/public/Concurrency/CMakeLists.txt

@@ -165,6 +165,7 @@ set(SWIFT_RUNTIME_CONCURRENCY_SWIFT_SOURCES
   PlatformExecutorLinux.swift
   PlatformExecutorWindows.swift
   PlatformExecutorOpenBSD.swift
+  PlatformExecutorFreeBSD.swift
 )
 
 set(SWIFT_RUNTIME_CONCURRENCY_NONEMBEDDED_C_SOURCES

stdlib/public/Concurrency/PlatformExecutorFreeBSD.swift

@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2020 - 2025 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#if !$Embedded && os(FreeBSD)
+
+import Swift
+
+// The default executors for now are Dispatch-based
+@available(SwiftStdlib 6.2, *)
+public struct PlatformExecutorFactory: ExecutorFactory {
+  public static let mainExecutor: any MainExecutor = DispatchMainExecutor()
+  public static let defaultExecutor: any TaskExecutor
+    = DispatchGlobalTaskExecutor()
+}
+
+#endif // os(FreeBSD)