[LLVMdev] Post-dominator data.

[Nick Lewycky]

Eli Friedman wrote:
> On Sat, May 30, 2009 at 3:54 PM, Evan Cheng<evan.cheng at apple.com> wrote:
>> Is our post-dom pass solid? I thought it's fair expensive so we avoid
>> using it.
> 
> Our "post-dom pass" is just the dom pass with a boolean set the other
> way. I don't see how it could be significantly more expensive.  I
> don't think any in-tree passes use it, though.

Many passes use and preserve the domtree. If you want to use the 
postdomtree it means that we'll have to calculate it just for you. As 
far as I know, that's the only reason it's discouraged.

Nick