Does anyone have any advice on how to get Xcode to compile Eigen for usage in the iOS simulator in a performance preserving manner?

I've integrated eigen into a project which Xcode compiles to simulator -- the code works however runs very slowly. Code which uses the Eigen::SelfAdjointEigenSolver<Eigen::MatrixXd> to compute eigendecompisiton of a covariance matrix executes in around 10 minutes on a linux machine -- but takes 2 hours to complete in the iOS simulator running on a mac pro with equivalent xeon processor ... Has anyone seen something like this before and have advice on how to debug?

My goal is to speedup execution of code that is compiled for iOS simulator -- the majority of this code targets iOS but some related functionality (which involves eigen) we are running from the iOS playground context for rapid iteration ...

Many thanks,
Ben

I've added a comment there: http://stackoverflow.com/questions/3663 ... -simulator.
Let's continue on SO.