Is the code for the FIR filter of Programming Example 5.3 reentrant? Explain.

Programming Example 5.3 An FIR Filter in C Here is a signal flow graph for an FIR filter: x(n) x0 bo y(n) b x1 b3 + The delay elements running vertically hold the input samples with the most recent sample at the top and the oldest one at the bottom. Unfortunately, the signal flow graph does not explicitly label all of the values that we use as inputs to operations, so the figure also shows the values (x) we need to operate on in our FIR loop. When we compute the filter function, we want to match the b's and x's. We will use our circular buffer for the x's, which change over time. We will use a standard array for the b's, which do not change. In order for the filter function to be able to use the same / value for both sets of data, we need to put the x data in the proper order. We can put the b data in a stan- dard array with bo being the first element. When we add a new x value, it becomes x0 and replaces the oldest data value in the buffer. This means that the buffer head moves from higher to lower values, not lower to higher as we might expect.