Function core_arch::x86::_mm256_unpacklo_epi8

pub unsafe fn _mm256_unpacklo_epi8(a: __m256i, b: __m256i) -> __m256i

This is supported on x86 and target feature avx2 only.

Unpacks and interleave 8-bit integers from the low half of each 128-bit lane of a and b.

#[cfg(target_arch = "x86")]
use std::arch::x86::*;
#[cfg(target_arch = "x86_64")]
use std::arch::x86_64::*;

let a = _mm256_setr_epi8(
    0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
    20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
);
let b = _mm256_setr_epi8(
    0, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, -11, -12, -13, -14, -15,
    -16, -17, -18, -19, -20, -21, -22, -23, -24, -25, -26, -27, -28, -29,
    -30, -31,
);

let c = _mm256_unpacklo_epi8(a, b);

let expected = _mm256_setr_epi8(
    0, 0, 1, -1, 2, -2, 3, -3, 4, -4, 5, -5, 6, -6, 7, -7, 16, -16, 17,
    -17, 18, -18, 19, -19, 20, -20, 21, -21, 22, -22, 23, -23,
);
assert_eq!(_mm256_movemask_epi8(_mm256_cmpeq_epi8(c, expected)), !0);

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