Trust me, at least on Intel, you do not want to write assembly inside your C/C++ code, unless it's just a couple of lines. The usual AT&T syntax will drive you

Trust me, at least on Intel, you do not want to write assembly inside your C/C++ code, unless it's just a couple of lines. The usual AT&T syntax will drive you nuts, and the additional syntax for embedding assembly only adds to the misery. For any reasonable amounts (say, you want a function or several) of assembly, you want Intel syntax and standalone assembly files. NASM is a great tool, although YASM should also be mentioned: https://yasm.tortall.net https://yasm.tortall.net — YASM is what I used when I optimized an H.264 decoder for Intel-compatible CPUs way back in 2005 or so.