pub unsafe fn _mm_mask_fnmsub_sd(
    a: __m128d,
    k: __mmask8,
    b: __m128d,
    c: __m128d
) -> __m128d
🔬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

Multiply the lower double-precision (64-bit) floating-point elements in a and b, and subtract the lower element in c from the negated intermediate result. Store the result in the lower element of dst using writemask k (the element is copied from c when mask bit 0 is not set), and copy the upper element from a to the upper element of dst.

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