binius_field/arch/
binary_utils.rs

1// Copyright 2024-2025 Irreducible Inc.
2
3use bytemuck::{must_cast_mut, must_cast_ref, AnyBitPattern, NoUninit};
4
5use crate::underlier::{NumCast, UnderlierType};
6
7/// Execute function `f` with a reference to an array of length `N` casted from `val`.
8#[allow(unused)]
9pub(super) fn as_array_ref<T, U, const N: usize, R>(val: &T, f: impl FnOnce(&[U; N]) -> R) -> R
10where
11	T: NoUninit + AnyBitPattern,
12	[U; N]: NoUninit + AnyBitPattern,
13{
14	let array = must_cast_ref(val);
15	f(array)
16}
17
18/// Execute function `f` with a mutable reference to an array of length `N` casted from `val`.
19#[allow(unused)]
20pub(super) fn as_array_mut<T, U, const N: usize>(val: &mut T, f: impl FnOnce(&mut [U; N]))
21where
22	T: NoUninit + AnyBitPattern,
23	[U; N]: NoUninit + AnyBitPattern,
24{
25	let array = must_cast_mut(val);
26	f(array);
27}
28
29/// Helper function to convert `f` closure that returns a value 1-4 bits wide to a function that returns i8.
30#[allow(dead_code)]
31#[inline]
32pub(super) fn make_func_to_i8<T, U>(mut f: impl FnMut(usize) -> T) -> impl FnMut(usize) -> i8
33where
34	T: UnderlierType,
35	U: From<T>,
36	u8: NumCast<U>,
37{
38	move |i| {
39		let elements_in_8 = 8 / T::BITS;
40		let mut result = 0u8;
41		for j in 0..elements_in_8 {
42			result |= u8::num_cast_from(U::from(f(i * elements_in_8 + j))) << (j * T::BITS);
43		}
44
45		result as i8
46	}
47}
binius_field/arch/binary_utils.rs

binius_field/arch/
binary_utils.rs
