Re: [boost] [offtopic] C++11 useful trick

Subject: Re: [boost] [offtopic] C++11 useful trick
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2012-07-03 14:29:24

On 07/03/2012 08:19 PM, Larry Evans wrote:

> Anyone know why, in this particular case, -O3 is faster than
> with no optimization?

Without optimizations

Execution times (seconds)
  phase setup             :   0.01
  phase parsing           :   0.10
  phase lang. deferred    :   0.54
  phase cgraph            :   3.50
  phase generate          :   4.04
  |name lookup            :   0.08
  |overload resolution    :   0.30

With optimizations

Execution times (seconds)
  phase setup             :   0.01
  phase parsing           :   0.09
  phase lang. deferred    :   0.52
  phase cgraph            :   0.40
  phase generate          :   0.92
  |name lookup            :   0.03
  |overload resolution    :   0.34

Optimizations done by the frontend resulted in much less symbols to 
compute the call graph for.