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Reverse Engineering the Constants in the Pentium FPU
Intel released the powerful Pentium processor in 1993, establishing a long-running brand of high-performance processors. 1 The Pentium incl...
Earlier Intel chips used binary algorithms called CORDIC, but the Pentium switched to polynomials to approximate these transcendental functions much faster. However, the Pentium takes advantage of its fast multiplier and larger ROM and uses polynomials instead, computing results two to three times faster than the 486 algorithm. Because the polynomial constants are optimized and my ROM data has bit errors, my program needed checks for inexact matches, both numerically and bitwise.
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