forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			90 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			90 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===----------------------------------------------------------------------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is dual licensed under the MIT and the University of Illinois Open
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| // Source Licenses. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // UNSUPPORTED: libcpp-has-no-threads
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| // UNSUPPORTED: c++98, c++03
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| 
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| // <future>
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| 
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| // class shared_future<R>
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| 
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| // void wait() const;
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| 
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| #include <future>
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| #include <cassert>
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| 
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| void func1(std::promise<int> p)
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| {
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|     std::this_thread::sleep_for(std::chrono::milliseconds(500));
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|     p.set_value(3);
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| }
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| 
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| int j = 0;
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| 
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| void func3(std::promise<int&> p)
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| {
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|     std::this_thread::sleep_for(std::chrono::milliseconds(500));
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|     j = 5;
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|     p.set_value(j);
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| }
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| 
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| void func5(std::promise<void> p)
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| {
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|     std::this_thread::sleep_for(std::chrono::milliseconds(500));
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|     p.set_value();
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| }
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| 
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| int main()
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| {
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|     typedef std::chrono::high_resolution_clock Clock;
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|     typedef std::chrono::duration<double, std::milli> ms;
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|     {
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|         typedef int T;
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|         std::promise<T> p;
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|         std::shared_future<T> f = p.get_future();
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|         std::thread(func1, std::move(p)).detach();
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|         assert(f.valid());
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|         f.wait();
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|         assert(f.valid());
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|         Clock::time_point t0 = Clock::now();
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|         f.wait();
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|         Clock::time_point t1 = Clock::now();
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|         assert(f.valid());
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|         assert(t1-t0 < ms(5));
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|     }
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|     {
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|         typedef int& T;
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|         std::promise<T> p;
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|         std::shared_future<T> f = p.get_future();
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|         std::thread(func3, std::move(p)).detach();
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|         assert(f.valid());
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|         f.wait();
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|         assert(f.valid());
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|         Clock::time_point t0 = Clock::now();
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|         f.wait();
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|         Clock::time_point t1 = Clock::now();
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|         assert(f.valid());
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|         assert(t1-t0 < ms(5));
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|     }
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|     {
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|         typedef void T;
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|         std::promise<T> p;
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|         std::shared_future<T> f = p.get_future();
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|         std::thread(func5, std::move(p)).detach();
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|         assert(f.valid());
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|         f.wait();
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|         assert(f.valid());
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|         Clock::time_point t0 = Clock::now();
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|         f.wait();
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|         Clock::time_point t1 = Clock::now();
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|         assert(f.valid());
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|         assert(t1-t0 < ms(5));
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|     }
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| }
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