pub unsafe fn _mm512_insertf64x4(
    a: __m512d,
    b: __m256d,
    const IMM8: i32
) -> __m512d
🔬This is a nightly-only experimental API. (stdarch_x86_avx512 #111137)
Available on (x86 or x86-64) and target feature avx512f and x86-64 only.
Expand description

Copy a to dst, then insert 256 bits (composed of 4 packed double-precision (64-bit) floating-point elements) from b into dst at the location specified by imm8.

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