chore: import upstream snapshot with attribution

test/expr/ExecutorScopeMultiThreadTest.cpp

@@ -0,0 +1,32 @@
+//
+//  ExecutorScopeMultiThreadTest.cpp
+//  MNNTests
+//
+//  Created by MNN on 2020/2/2.
+//  Copyright © 2018, Alibaba Group Holding Limited
+//
+
+#include <MNN/expr/ExecutorScope.hpp>
+#include "MNNTestSuite.h"
+#include "MNN_generated.h"
+#include <thread>
+
+using namespace MNN::Express;
+
+class ExecutorScopeMultiThreadTest : public MNNTestCase {
+public:
+    virtual bool run(int precision) {
+        std::vector<std::thread> threads;
+        for (int i = 0; i < 4; ++i) {
+            threads.emplace_back([&]() {
+                ExecutorScope scope(ExecutorScope::Current());
+            });
+        }
+        for (auto& t : threads) {
+            t.join();
+        }
+        return true;
+    }
+};
+
+MNNTestSuiteRegister(ExecutorScopeMultiThreadTest, "expr/ExecutorScopeMultiThread");