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  1. JDK
  2. JDK-6823354

Add intrinsics for {Integer,Long}.{numberOfLeadingZeros,numberOfTrailingZeros}()

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        These methods can be instrinsified by using bit scan, bit test, and population count instructions. It seems it's not worth to instrinsify lowestOneBit() too, as it already boilds down to about 2 or 3 machine instructions.

        Some of these methods can be used in BigInteger and maybe other classes in the JDK.
        I removed highestOneBit from that CR as it's not clear the benefit is worth the changes. I might open another one in the future.

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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-2179100 Add intrinsics for {Integer,Long}.{numberOfLeadingZeros,numberOfTrailingZeros}()

            • P5 - Cosmetic problem like misspelt words or misaligned text.
            • Closed

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-2180639 Add intrinsics for {Integer,Long}.{numberOfLeadingZeros,numberOfTrailingZeros}()

            • P5 - Cosmetic problem like misspelt words or misaligned text.
            • Closed
            relates to

            Bug - A problem which impairs or prevents the functions of the product. JDK-7100757 The BitSet.nextSetBit() produces incorrect result in 32bit VM on Sparc

            • P3 - Major loss of function.
            • Resolved

            Enhancement - null JDK-6832035 BigInteger and MutableBigInteger should use Integer bit-twiddling methods

            • P5 - Cosmetic problem like misspelt words or misaligned text.
            • Closed

            Bug - A problem which impairs or prevents the functions of the product. JDK-6996240 The BitSet.length method sometimes returns an index+1 value less than that of the highest bit set.

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Closed

            Enhancement - null JDK-8035857 Add tests to verify correctness of operations with BMI1 and LZCNT instructions

            • P2 - Crashes, loss of data, severe memory leak.
            • Resolved

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                twisti Christian Thalinger
                twisti Christian Thalinger
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