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%% Copyright: 2010 Integrated Sytems Laboratory, ETH Zurich
%%            http://www.iis.ee.ethz.ch/~sha3
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function y = FFT_8(y)

yo = y;

y = butterfly(y, 0, 4, 0);
y = butterfly(y, 1, 5, 1);
y = butterfly(y, 2, 6, 2);
y = butterfly(y, 3, 7, 3);
   
y(6+1) = reduce(y(6+1));
y(7+1) = reduce(y(7+1));

y = butterfly(y, 0, 2, 0);
y = butterfly(y, 4, 6, 0);
y = butterfly(y, 1, 3, 2);
y = butterfly(y, 5, 7, 2);
   
y(7+1) = reduce(y(7+1));

y = butterfly(y, 0, 1, 0);
y = butterfly(y, 2, 3, 0);
y = butterfly(y, 4, 5, 0);
y = butterfly(y, 6, 7, 0);

y(0+1) = extrareduce(y(0+1));
y(1+1) = extrareduce(y(1+1));
y(2+1) = extrareduce(y(2+1));
y(3+1) = extrareduce(y(3+1));
y(4+1) = extrareduce(y(4+1));
y(5+1) = extrareduce(y(5+1));
y(6+1) = extrareduce(y(6+1));
y(7+1) = extrareduce(y(7+1));