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  1. JDK
  2. JDK-8029501

BigInteger division algorithm selection heuristic is incorrect

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      b120
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        Currently Burnikel-Ziegler division is selected if

        (dividend.length < BURNIKEL_ZIEGLER_THRESHOLD || divisor.length < BURNIKEL_ZIEGLER_THRESHOLD)

        is FALSE. This causes significant performance regression (up to about 100%) for cases where dividend.length - divisor.length < OFFSET where 0 < OFFSET <= 2*BURNIKEL_ZIEGLER_THRESHOLD. A better algorithm selection heuristic is to select B-Z division if

        (divisor.length < BURNIKEL_ZIEGLER_THRESHOLD || dividend.length - divisor.length < BURNIKEL_ZIEGLER_OFFSET)

        is FALSE, i.e., to require that the int-length of the dividend exceed that of the divisor by a given minimum value.

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                • Assignee:
                  bpb Brian Burkhalter
                  Reporter:
                  bpb Brian Burkhalter
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