This is a syntax highlighting file for swift intermediate language files, to use this, add the code to your .emacs file:
(add-to-list 'load-path "path-to-sil-mode")
(require 'sil-mode)
NOTE: this major mode was shamelessly modified from llvm-mode, if you notice missing or incorrect syntax highlighting, please contact me, or you can fork and fix the problem then send a pull request, it will be most appreciated. Thank you.