Roadmap to 1.0

[gnzlbg]

This is a mind dump of what I'd like to see in for 1.0, API wise, functionality wise, and algorithmic wise.

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• The big goals for 1.0 are:
  • API for Word algorithms.
  • API for SWAR algorithms.
  • API for algorithms on Word slices.
  • i128/u128 support.
  • Support stable Rust.

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• The word algorithms I would like to see in the library for 1.0 are:
  • Basic algorithms from N3864 / stdcxx-bitops.
  • Morton indices algorithms:
    • BMI2.0
    • Magicbits
    • LUT
    • sLUT
  • Greatest common divisor: Implement greatest common divisor algorithm #11.
  • Hamming distance: Implement Hamming Distance algorithm #2 .
  • Swap by primitives.
  • parallel_bits_deposit/extract-right and extract_bits_right (see compress and expand.
  • Butterfly network.
  • sheep-and-goats
  • deposit/extract flip variants (left and right).
  • omega-flip network.
  • sign extend
  • gray code (and inverse)
  • is x a contiguous sequence of 1 bits ?

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• The subword algorithms (SWAR) I would like to see in the library for 1.0 are:
  • broadcast/deposit all: fill every subword with value
  • gather/extract: extract the value of a subword
  • broadcast/deposit: fill subword i with value
  • count_ones/count_zeros/ leading ones/ leading zeros / trailing ones / trailing zeros in subword i
  • does one subword contain the value zero ?
  • parity of the subword i
  • binary operations for the i-th subword values (and for all values) of the words x and y, with/without wrapping/saturation, signed/unsigned, etc: : : add/sub/mul/div/mod ...
  • unary operations for the i-th subword values (and for all values) of the word x: neg, increment, decrement, abs, ..
  • logical operations for the i-th subword values (and for all values) of the words x and y: eq, neq, leq,geq, le, ge,
  • bitwise operations for the i-th subword values (and for all values) of the word x: shifts, and/or/xor/rotation...
  • "horizontal" binary operations (for adjacent subwords in a word): add/sub/mul/...

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• The word slices algorithms I would like to see in the library for 1.0 are:
  • count non-zero/zero bytes (use the byteorder crate for this?)
  • bit matrices: inversion, transposition

[MathGeniusJodie]

a "clear leading one" would be nice