Rasm2 is part of the radare2 framework, and assembles and disassembles files or hexpair strings without having to open r2. After installing radare2 we can execute rasm2 to quickly assemble and disassemble strings.

rasm2 -a arm -b 64 "mov  x2, xzr"

e2031faa

And the reverse.

rasm2 -a arm -b 64 -d e2031faa

mov x2, xzr

This is great and excatly what I want for learning, but it would be nicer if it was more inline. The command never really changes, and I wonder if I can do better.

The code blocks above are ran by using org babel with shell-mode. Under the hood, it executes whats in the src bock and then displays the results in the buffer. Now, if I could have the rasm2 command above as a snippet then it would save me a lot of repitition, but I can do one better.

My research into linking rasm2 to org babel led me to this post. The author actually provides the code to make this work, however there is a problem. When I edit code blocks in org-mode I like to enter a temprary buffer with C ', with the code from the post I get an error that no such language: rasm2-mode. This means that there is no C ' for me.

Tidying up the code and googling around a bit, I ended up with ob-rasm2, and adding (add-to-list 'org-src-lang-modes '("rasm2" . asm)) allows editiing with C ' by tricking org-mode in thinking that your editing in asm. All thats left to do is show the same example above :).

mov x2, xzr

\xe2\x03\x1f\xaa

And the reverse.

e2031faa

mov x2, xzr