[llvm-commits] [llvm] r85369 - /llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

[Chris Lattner]

On Oct 27, 2009, at 8:44 PM, Dan Gohman wrote:

> Author: djg
> Date: Tue Oct 27 22:44:30 2009
> New Revision: 85369
>
> URL: http://llvm.org/viewvc/llvm-project?rev=85369&view=rev
> Log:
> Rewrite SelectionDAG::isPredecessorOf to be iterative instead of
> recursive to avoid consuming extraordinary amounts of stack space
> when processing tall graphs.

Hi Dan,

Would it make sense or be possible to make this be a tri-state method  
that returns "yes, no or don't know"?  That way it could bail out if  
the search depth gets too bad, bounding the amount of work.

Better yet would be to fix the clients to not need this of course :)

-Chris