Re: [Boost-users] [MSM] state transitions and exceptions

Subject: Re: [Boost-users] [MSM] state transitions and exceptions
From: Christophe Henry (christophe.j.henry_at_[hidden])
Date: 2012-04-01 16:13:02

> on Thu Mar 29 2012, "Christophe Henry" 
> <christophe.j.henry-AT-googlemail.com> wrote:
>
>>> Jurai,
>>>
>>> On Thu, Mar 29, 2012 at 7:07 PM, Juraj Ivančić
>>> <juraj.ivancic_at_[hidden]> wrote:
>>>> I know how you feel. MSM is an awesome library. Unfortunately
>>>> compilers tend
>>>> to disagree :)
>>
>> I'd say compilers should be blamed for this ;-) (I'm still wondering
>> how it can be that compilers make such a poor use of my 6 cores with
>> hyperthreading when compile a single object file...)
>
> There isn't much inherent parallelism to exploit in C++ compilation of a
> single translation unit.
>
> -- 
> Dave Abrahams
> BoostPro Computing
> http://www.boostpro.com

I'm not an expert in this field, but this surprises me a bit.
I understand that there is not much parallelism in parsing a file, but 
after?
Taking msm as example. Most of the compile time comes from template 
instanciations of the function process_event for every event type. Adding 
support for a new event adds roughly the same compilation time. Every 
process_event has little in common with other process_event instances. What 
prevents the compiler from handling each at the same time?

Christophe