59 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			59 lines
		
	
	
		
			2.0 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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#ifndef SUPPORT_TRACKED_VALUE_H
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#define SUPPORT_TRACKED_VALUE_H
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#include <cassert>
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struct TrackedValue {
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    enum State { CONSTRUCTED, MOVED_FROM, DESTROYED };
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    State state;
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    TrackedValue() : state(State::CONSTRUCTED) {}
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    TrackedValue(TrackedValue const& t) : state(State::CONSTRUCTED) {
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        assert(t.state != State::MOVED_FROM && "copying a moved-from object");
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        assert(t.state != State::DESTROYED  && "copying a destroyed object");
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    }
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#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
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    TrackedValue(TrackedValue&& t) : state(State::CONSTRUCTED) {
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        assert(t.state != State::MOVED_FROM && "double moving from an object");
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        assert(t.state != State::DESTROYED  && "moving from a destroyed object");
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        t.state = State::MOVED_FROM;
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    }
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#endif
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    TrackedValue& operator=(TrackedValue const& t) {
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        assert(state != State::DESTROYED && "copy assigning into destroyed object");
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        assert(t.state != State::MOVED_FROM && "copying a moved-from object");
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        assert(t.state != State::DESTROYED  && "copying a destroyed object");
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        state = t.state;
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        return *this;
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    }
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#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
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    TrackedValue& operator=(TrackedValue&& t) {
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        assert(state != State::DESTROYED && "move assigning into destroyed object");
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        assert(t.state != State::MOVED_FROM && "double moving from an object");
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        assert(t.state != State::DESTROYED  && "moving from a destroyed object");
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        state = t.state;
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        t.state = State::MOVED_FROM;
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        return *this;
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    }
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#endif
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    ~TrackedValue() {
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        assert(state != State::DESTROYED && "double-destroying an object");
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        state = State::DESTROYED;
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    }
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};
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#endif // SUPPORT_TRACKED_VALUE_H
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