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Shifting and moving bits in place are the common operators in hardware design. In this lecture, 
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I will explain how to describe these operations in Vivado-HLS.
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The builtin shift operators in C/C++ are overloaded to be used for the HLS arbitrary-precision 
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data types. There are two bitwise shift operators:
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Right shift (>>),
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Left shift (<<).
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There are two versions of each shift operator:  unsigned and signed. A negative value applied to the
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RHS of the signed version reverses the shift direction.
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These are four examples of different shift operators. 
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The first one is a 3-bit positive shift right. The second one is a 3-bit negative shift 
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right which is equal to 3-bit  shift left.
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The third one is a 3-bit positive shift left. And the last one is a 3-bit negative shift left 
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which is equal to 3-bit  shift right.
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Vivado HLS provides two member functions to perform rotate operations on arbitrary-precision 
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data types. The rrotate member function performs the rotate right. And the lrotate member function 
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performs the rotate left 
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This lecture is the last in this section that explained the design concepts and techniques. So the 
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next lecture will give you a couple of hardware designs as exercises through which you review and master 
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the proposed techniques in this section. 
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These are our takeaway messages.
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Vivado-HLS has overloaded the native C/C++ shift operators.
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Rotate operations are provided through member functions.
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Now the quiz question. Find the values of r1, r2 and r3 after running this code snippet in 
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Vivado-HLS.