Automatic program obfuscation

[helios]

A while ago I read about how some code obfuscators will generate a virtual machine with a random instruction set (e.g. an instruction might be "add 7 to register 1 and push the program counter onto the stack") and then compile a program in some high level language into bytecode for this instruction set. I've been looking for resources on this and similar techniques, but I can't seem to find anything.

Does anyone know of books or articles where I can read about it?

[mbozzi]

One obfuscator that uses the technique you describe is Christian Colberg's Tigress:
http://tigress.cs.arizona.edu/

The author has a "learn more" page on his site:
http://tigress.cs.arizona.edu/learning.html

[helios]

I know, I've checked out the book already! Unfortunately it doesn't seem to describe that particular technique...