pub unsafe fn _mm512_mask_insertf64x4<const IMM8: i32>(
    src: __m512d,
    k: u8,
    a: __m512d,
    b: __m256d
) -> __m512d
🔬 This is a nightly-only experimental API. (stdsimd)
This is supported on x86-64 and target feature avx512f only.
Expand description

Copy a to tmp, then insert 256 bits (composed of 4 packed double-precision (64-bit) floating-point elements) from b into tmp at the location specified by imm8. Store tmp to dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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