Fix Lock and mark a few tests unsupported

Author: Azoy

stdlib/public/Reflection/Sources/_Runtime/Utils/Lock.swift

@@ -23,41 +23,29 @@ func _lockLock(_: UnsafeRawPointer)
 @_silgen_name("_swift_reflection_lock_unlock")
 func _lockUnlock(_: UnsafeRawPointer)
 
-class Lock<T> {
-  var value: T
+struct Lock<T> {
+  var storage: ManagedBuffer<T, UInt8>
 
-  var mutex: UnsafeRawPointer {
-    UnsafeRawPointer(
-      Builtin.projectTailElems(self, UnsafeRawPointer.self)
-    )
-  }
-
-  init(_ x: T) {
-    value = x
-  }
-
-  static func create(with initialValue: T) -> Lock<T> {
-    let lock = Builtin.allocWithTailElems_1(
-      Lock<T>.self,
-      _lockSize()._builtinWordValue,
-      UnsafeRawPointer.self
-    )
-
-    lock.value = initialValue
+  init(initialValue: T) {
+    storage = .create(minimumCapacity: _lockSize()) {
+      $0.withUnsafeMutablePointerToElements {
+        _lockInit(UnsafeRawPointer($0))
+      }
 
-    _lockInit(lock.mutex)
-
-    return lock
+      return initialValue
+    }
   }
 
   func withLock<U>(_ body: @Sendable (inout T) throws -> U) rethrows -> U {
-    _lockLock(mutex)
+    try storage.withUnsafeMutablePointers { header, elements in
+      _lockLock(UnsafeRawPointer(elements))
 
-    defer {
-      _lockUnlock(mutex)
-    }
+      defer {
+        _lockUnlock(UnsafeRawPointer(elements))
+      }
 
-    return try body(&value)
+      return try body(&header.pointee)
+    }
   }
 }
 

stdlib/public/Reflection/Sources/_Runtime/Utils/PointerStuff.swift

@@ -12,7 +12,7 @@
 import Swift
 
 @_alwaysEmitIntoClient
-func unsafeBitCast<T, U>(_ x: T, to type: U.Type = U.self) -> U {
+func unsafeBitCast<T, U>(_ x: T, toDefault type: U.Type = U.self) -> U {
   Swift.unsafeBitCast(x, to: type)
 }
 

stdlib/public/Reflection/Sources/_Runtime/Utils/TypeCache.swift

@@ -17,7 +17,7 @@ struct TypeCache {
 
   @available(SwiftStdlib 5.9, *)
   init() {
-    cache = Lock.create(with: [:])
+    cache = Lock<[Key: Any.Type?]>(initialValue: [:])
   }
 }
 
@@ -192,7 +192,7 @@ var typeCache: TypeCache = {
   var result = TypeCache()
 
   result.cache.withLock {
-    $0.reserveCapacity(50)
+    $0.reserveCapacity(25)
   }
 
   return result

test/stdlib/_Runtime/ContextDescriptor/StructDescriptor.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/FunctionMetadata.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/Metadata.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/MetatypeMetadata.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/StructMetadata.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/TupleMetadata.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/TypeMetadata.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime
 

test/stdlib/_Runtime/Metadata/ValueWitnessTable.swift

@@ -1,6 +1,8 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
 
+// UNSUPPORTED: freestanding
+
 import StdlibUnittest
 import _Runtime