- This is Guy L. Steele Jr.'s parallel suffix algorithm for bit extraction (U.S. Patent 6715066).
- Bits of x that correspond to 1-bits in m are shifted low and made consecutive, preserving relative order.
- The method masks x with m to isolate such bits and then repeatedly shifts 1-bits of x low by powers of two.
- A 1-bit in x with n less significant 0-bits in m is shifted low by a series of powers of two that sum to n.

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