Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/compiler-rt/lib/scudo/scudo_tsd_exclusive.inc

@@ -0,0 +1,46 @@
+//===-- scudo_tsd_exclusive.inc ---------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// Scudo exclusive TSD fastpath functions implementation.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef SCUDO_TSD_H_
+# error "This file must be included inside scudo_tsd.h."
+#endif  // SCUDO_TSD_H_
+
+#if SCUDO_TSD_EXCLUSIVE
+
+enum ThreadState : u8 {
+  ThreadNotInitialized = 0,
+  ThreadInitialized,
+  ThreadTornDown,
+};
+__attribute__((tls_model("initial-exec")))
+extern THREADLOCAL ThreadState ScudoThreadState;
+__attribute__((tls_model("initial-exec")))
+extern THREADLOCAL ScudoTSD TSD;
+
+extern ScudoTSD FallbackTSD;
+
+ALWAYS_INLINE void initThreadMaybe(bool MinimalInit = false) {
+  if (LIKELY(ScudoThreadState != ThreadNotInitialized))
+    return;
+  initThread(MinimalInit);
+}
+
+ALWAYS_INLINE ScudoTSD *getTSDAndLock() {
+  if (UNLIKELY(ScudoThreadState != ThreadInitialized)) {
+    FallbackTSD.lock();
+    return &FallbackTSD;
+  }
+  return &TSD;
+}
+
+#endif  // SCUDO_TSD_EXCLUSIVE