Not sure if there are any books around LLVM or gcc, but there is a lot of up to date texts.

Grune at al., "Modern Compiler Design",

Appel, "Modern Compiler Implementation in ML",

and many more.

P.S. Because of a slow-ban, adding another one to this answer. This is the best source on SSA:

http://www.cri.ensmp.fr/people/pop/papers/2006-12-thesis.pdf