They are explicitly specified by all major CPU vendors. https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/best-pr

They are explicitly specified by all major CPU vendors. https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/best-practices/data-operand-independent-timing-isa-guidance.html https://www.intel.com/content/www/us/en/developer/articles/t...