# Function core::arch::x86::_mm_rsqrt14_sd[−][src]

    pub unsafe fn _mm_rsqrt14_sd(a: __m128d, b: __m128d) -> __m128d

🔬 This is a nightly-only experimental API. (`stdsimd` #48556)
This is supported on x86 and target feature `avx512f` only.

Compute the approximate reciprocal square root of the lower double-precision (64-bit) floating-point element in b, store the result in the lower element of dst, and copy the upper element from a to the upper element of dst. The maximum relative error for this approximation is less than 2^-14.

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