This is still one of the most trusted sources for low-level optimization!<p>uops.info is also very handy for x86 ( <a href="https://uops.info/table_overview.html" rel="nofollow">https://uops.info/table_overview.html</a> ).<p>But if you are just starting, those may be a bit overwhelming. In that case, check out the official intrinsics guides for x86 from Intel ( <a href="https://software.intel.com/sites/landingpage/IntrinsicsGuide/" rel="nofollow">https://software.intel.com/sites/landingpage/IntrinsicsGuide...</a> ) and a separate one for Arm ( <a href="https://developer.arm.com/architectures/instruction-sets/intrinsics/" rel="nofollow">https://developer.arm.com/architectures/instruction-sets/int...</a> )