Tags / Equivalents

Purpose: Returns a vector containing a refined approximation of the reciprocal square roots of the corresponding elements of the source vector. This function provides an implementation-dependent greater precision than vec_rsqrte.

Result value: Each element of output contains a refined approximation of the reciprocal square root of the corresponding element of a.

Endian considerations: None.

Notes:

• The example implementations assume that a register h initially contains the floating-point value 0.5 in each element (single- or double-precision as appropriate).

• For finite square roots, this intrinsic guarantees at least 23 bits of accuracy for single-precision floating point, and at least 52 bits of accuracy for double-precision floating point.

Floating-point Reciprocal Square Root Estimate. This instruction calculates an approximate square root for each vector element in the source SIMD&FP register, places the result in a vector, and writes the vector to the destination SIMD&FP register.

Purpose: Compute the approximate reciprocal square root of packed single-precision (32-bit) floating-point elements in a, and store the results in output. The maximum relative error for this approximation is less than 1.5*2^-12.

Result value:

Endian considerations: None.

Floating-point Reciprocal Square Root Estimate. This instruction calculates an approximate square root for each vector element in the source SIMD&FP register, places the result in a vector, and writes the vector to the destination SIMD&FP register.