In 1993, Intel introduced the Pentium processor, which includes a complex circuit to multiply by three. This circuit is part of the floating-point multiplier, using base-8 multiplication which is faster than binary. The Pentium uses Booth’s multiplication algorithm for difficult multiples like 7. The x3 circuit combines carry lookahead, Kogge-Stone addition, and carry-select addition to maximize performance. The Kogge-Stone approach is used in the Pentium’s recursive, hierarchical carry lookahead for 64-bit addition. The carry-select adder is employed in each 8-bit chunk of the x3 circuit to compute the sum and carry quickly. The Pentium’s x3 multiplier architecture allows for parallel computation, resulting in fast addition.
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