Dominator algorithms

Include the following commonly used dominator algorithms:

1. Purdom algorithm
2. Iterative algorithm
3. Cooper algorithm
4. Tarjan algorithm (both simple and sophisticated versions)
5. TODO Semi-NCA algorithm

Warning: Just for learning, not intended as a library. I won't maintain it.

I also wrote a blog about dominator (in Chinese): Dominator 讲解及其相关性质的证明

References

TODO: Give the details of each reference.

• Building an optimizing compiler 1st
• Compilers: Principles, Techniques, and Tools 2nd
• Engineering a Compiler 3rd
• A Simple, Fast Dominance Algorithm
• A Fast Algorithm for Finding Dominators in a Flowgraph
• Applications of Path Compression on Balanced Tree