ff: refactor find_naf and add unit tests
#896
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tcoratger
requested review from
z-tech,
weikengchen and
tyshko-rostyslav
and removed request for
a team
Pratyush
reviewed
Nov 30, 2024
ff/src/biginteger/arithmetic.rs
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Comment on lines
158
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178
| while num.iter().any(|&x| x != 0) { | ||
| let z = if num[0] & 1 == 1 { | ||
| let z = 2 - (num[0] % 4) as i8; | ||
| // Choose the appropriate operation: subtract (sbb) if z >= 0, otherwise add (adc). | ||
| let op = if z >= 0 { sbb } else { adc }; | ||
| num.iter_mut() | ||
| .zip(ark_std::iter::once(&(z.abs() as u64)).chain(ark_std::iter::repeat(&0))) | ||
| .fold(0, |carry, (a, b)| op(a, *b, carry)); | ||
| z | ||
| } else { | ||
| z = 0; | ||
| } | ||
| 0 | ||
| }; | ||
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| res.push(z); | ||
| div2(&mut num); | ||
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| // Perform an in-place division of `num` by 2, using bit-shifting. | ||
| num.iter_mut().rev().fold(0, |carry, x| { | ||
| let next_carry = *x << 63; | ||
| *x = (*x >> 1) | carry; | ||
| next_carry | ||
| }); |
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Thanks for the PR! I think I like the old code structure slightly better since it separates out the arithmetic logic from the algorithm logic. I do like the new implementations of the arithmetic better, so maybe we can go back to the old code structure but with the new arithmetic impls?
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Fixed, I've also added a more complete documentation inside the function for the reader to understand the various operations that are performed.
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Description
closes: #XXXX
Before we can merge this PR, please make sure that all the following items have been
checked off. If any of the checklist items are not applicable, please leave them but
write a little note why.
Pendingsection inCHANGELOG.mdFiles changedin the GitHub PR explorer