程式語言 - GNU - int 0x80、sysenter、syscall

參考資訊：
http://www.int80h.org/
https://stackoverflow.com/questions/15598700/syscall-or-sysenter-on-32-bits-linux
https://reverseengineering.stackexchange.com/questions/2869/how-to-use-sysenter-under-linux
https://unix.stackexchange.com/questions/472881/what-does-sysenter-do-in-64-bit-long-mode-on-linux
https://stackoverflow.com/questions/29833938/what-is-the-compatible-subset-of-intels-and-amds-x86-64-implementations
https://stackoverflow.com/questions/29783896/why-does-syscall-compile-in-nasm-32-bit-output-while-popa-does-not-compile-in-64/29784932#29784932

使用時機：