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Signed Binary Multiplication

The multiplication $a \times b$ has a predicted lookahead of between (n+2) and (n+5). Figure 7.2 illustrates this by plotting the lookahead at each digit. A lookahead of (n+3) or (n+4) appears to be more usual, although the minimum and maximum lookaheads are reached occasionally.

Figure 7.2: Lookahead required at each output digit when computing $a \times b$

\includegraphics [width=13cm]{real_sbmul.eps}\end{center}\end{figure}

Martin Escardo