AST Reader/Writer documentation

Hi guys,

while working on this patch[1] (ObjC boxable C structures) I’ve faced with some issues related to serialization/deserialization (ASTReader/ASTWriter).

The question is: where I can find some documentation about algorithms/approach used in the implementation?

I’d appreciate any links, hints, directions.

[1] http://thread.gmane.org/gmane.comp.compilers.clang.scm/111938

Thank you in advance,
Alex