1 files changed, 91 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_mutexset.h b/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_mutexset.h
new file mode 100644
index 000000000000..aabd361e6afd
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_mutexset.h
@@ -0,0 +1,91 @@
+//===-- tsan_mutexset.h -----------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+// MutexSet holds the set of mutexes currently held by a thread.
+//===----------------------------------------------------------------------===//
+#ifndef TSAN_MUTEXSET_H
+#define TSAN_MUTEXSET_H
+
+#include "tsan_defs.h"
+
+namespace __tsan {
+
+class MutexSet {
+ public:
+  // Holds limited number of mutexes.
+  // The oldest mutexes are discarded on overflow.
+  static constexpr uptr kMaxSize = 16;
+  struct Desc {
+    uptr addr;
+    StackID stack_id;
+    u32 seq;
+    u32 count;
+    bool write;
+
+    Desc() { internal_memset(this, 0, sizeof(*this)); }
+    Desc(const Desc& other) { *this = other; }
+    Desc& operator=(const MutexSet::Desc& other) {
+      internal_memcpy(this, &other, sizeof(*this));
+      return *this;
+    }
+  };
+
+  MutexSet();
+  void Reset();
+  void AddAddr(uptr addr, StackID stack_id, bool write);
+  void DelAddr(uptr addr, bool destroy = false);
+  uptr Size() const;
+  Desc Get(uptr i) const;
+
+ private:
+#if !SANITIZER_GO
+  u32 seq_ = 0;
+  uptr size_ = 0;
+  Desc descs_[kMaxSize];
+
+  void RemovePos(uptr i);
+#endif
+};
+
+// MutexSet is too large to live on stack.
+// DynamicMutexSet can be use used to create local MutexSet's.
+class DynamicMutexSet {
+ public:
+  DynamicMutexSet();
+  ~DynamicMutexSet();
+  MutexSet* operator->() { return ptr_; }
+  operator MutexSet*() { return ptr_; }
+  DynamicMutexSet(const DynamicMutexSet&) = delete;
+  DynamicMutexSet& operator=(const DynamicMutexSet&) = delete;
+
+ private:
+  MutexSet* ptr_;
+#if SANITIZER_GO
+  MutexSet set_;
+#endif
+};
+
+// Go does not have mutexes, so do not spend memory and time.
+// (Go sync.Mutex is actually a semaphore -- can be unlocked
+// in different goroutine).
+#if SANITIZER_GO
+MutexSet::MutexSet() {}
+void MutexSet::Reset() {}
+void MutexSet::AddAddr(uptr addr, StackID stack_id, bool write) {}
+void MutexSet::DelAddr(uptr addr, bool destroy) {}
+uptr MutexSet::Size() const { return 0; }
+MutexSet::Desc MutexSet::Get(uptr i) const { return Desc(); }
+DynamicMutexSet::DynamicMutexSet() : ptr_(&set_) {}
+DynamicMutexSet::~DynamicMutexSet() {}
+#endif
+
+}  // namespace __tsan
+
+#endif  // TSAN_MUTEXSET_H