[llvm-commits] Review request: dominator tree construction speedup

[Chris Lattner]

On Nov 22, 2010, at 1:56 AM, Cameron Zwarich wrote:

> There is a cheap speedup in the implementation of the Lengauer-Tarjan algorithm. In the main loop, when you are about to add a node to its semidominator's bucket, you first check if the semidominator is the node's parent. If it is, then you know that its immediate dominator will be its parent and there is no need to put it into the bucket for later processing.
> 
> This is a 9.7% speedup running domtree on test-suite.

Wow, nice.  Please add a comment explaining this, otherwise looks great!  Please commit,

-Chris