_mm_rsqrt_ss
Classification
SSE_ALL, Elementary Math Functions, CPUID Test: SSE
Header File
xmmintrin.h
Instruction
RSQRTSS xmm, xmm
Synopsis
 _mm_rsqrt_ss(__m128 a);
Description
Compute the approximate reciprocal square root of the lower single-precision (32-bit) floating-point element in "a", 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 1.5*2^-12.
Operation
dst[31:0] := (1.0 / SQRT(a[31:0]))
dst[127:32] := a[127:32]