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  1. JDK
  2. JDK-8190869

C2: missing strength reduction of Math.pow(x, 2.0D) to x*x

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        Description

        There's a performance regression in 9 (compared to 8) in Math.pow(x, 2.0D).

        Math.pow() was rewritten in 9 (see JDK-8145688), but it doesn't have special case for power-of-two in C2 intrinsic implementation.

        Original report:
        https://www.reddit.com/r/java/comments/7bbh72/i_think_i_found_piece_of_code_which_is_8_times/

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                Assignee:
                vlivanov Vladimir Ivanov
                Reporter:
                vlivanov Vladimir Ivanov
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