_mm_rsqrt28_round_ss
Classification
AVX-512, Elementary Math Functions, CPUID Test: AVX512ER
Header File
immintrin.h
Instruction
VRSQRT28SS xmm, xmm, xmm {sae}
Synopsis
 _mm_rsqrt28_round_ss(__m128 a, __m128 b, int sae);
Description
Compute the approximate reciprocal square root of the lower single-precision (32-bit) floating-point element in "b", store the result in the lower element of "dst", and copy the upper 3 packed elements from "a" to the upper elements of "dst". The maximum relative error for this approximation is less than 2^-28. [sae_note]
Operation
dst[31:0] := (1.0 / SQRT(b[31:0]))
dst[127:32] := a[127:32]
dst[MAX:128] := 0