What taught me how to write a compiler was the BYTE magazine 1978-08 .. 09 issues which had a listing for a Tiny Pascal compiler. Reading the listing was magical.

What taught me how to write an optimizer was a Stanford summer course taught by Ullman and Hennessy.

The code generator was my own concoction, and is apparently quite unlike any other one out there!

I have the Dragon Book, but have never actually read it. So sue me.