pub unsafe fn _mm256_mask_popcnt_epi32(
    src: __m256i,
    k: u8,
    a: __m256i
) -> __m256i
🔬This is a nightly-only experimental API. (stdsimd)
Available on non-crate feature miri-test-libstd and x86-64 only.
Expand description

For each packed 32-bit integer maps the value to the number of logical 1 bits.

Uses the writemask in k - elements are copied from src if the corresponding mask bit is not set. Otherwise the computation result is written into the result.

Intel’s documentation