If your computer was built after 1999, it probably supports the SSE instruction set. It contains the _mm_rsqrt_ps instruction, which is faster and will give you four reciprocal square roots at once: https://www.intel.com/content/www/us/en/docs/intrinsics-guid...
That being said, the techniques discussed here are not totally irrelevant (yet). There still exists some hardware with fast instructions for float/int conversion, but lacking rsqrt, sqrt, pow, log instructions, which can all be approximated with this nice trick.
That being said, the techniques discussed here are not totally irrelevant (yet). There still exists some hardware with fast instructions for float/int conversion, but lacking rsqrt, sqrt, pow, log instructions, which can all be approximated with this nice trick.