_mm512_mask_rsqrt14_pd
Classification
AVX-512, Elementary Math Functions, CPUID Test: AVX512F
Header File
immintrin.h
Instruction
VRSQRT14PD zmm {k}, zmm
Synopsis
 _mm512_mask_rsqrt14_pd(__m512d src, __mmask8 k, __m512d a);
Description
Compute the approximate reciprocal square root of packed double-precision (64-bit) floating-point elements in "a", and store the results in "dst" using writemask "k" (elements are copied from "src" when the corresponding mask bit is not set). The maximum relative error for this approximation is less than 2^-14.
Operation
FOR j := 0 to 7
	i := j*64
	IF k[j]
		dst[i+63:i] := (1.0 / SQRT(a[i+63:i]))
	ELSE
		dst[i+63:i] := src[i+63:i]
	FI
ENDFOR
dst[MAX:512] := 0