Re: [boost] [Proto] Inlining failure on gcc 4.x on 64bits linux

Subject: Re: [boost] [Proto] Inlining failure on gcc 4.x on 64bits linux
From: Eric Niebler (eric_at_[hidden])
Date: 2010-07-19 17:29:22

On 7/19/2010 2:30 PM, joel falcou wrote:
> I'm reporting this performances problem we encountered today.
> We have a large expression operating on table of 51200000 elements;
> 
> In 32bits mode, our proto code for NT² works perfectly and output a
> gprofile like:
> http://codepad.org/Uyyvkq4X
> 
> rutniem performance sis somethign like 1.5s for the whoel computation.
> 
> In 64bits on linus using gcc 4.4 or 4.3, we got a massive 8.6s of
> runtime (!!)
> and the profile is:
> 
> http://codepad.org/6VgRsbyR
> 
> As it seems the call to proto::default_ is not inlined (hence the 5.12M
> calls) and take 80% of the runtime.
> 
> I don't thing anything is 32/64bits specific in proto  so is it a bug in
> gcc ?

There is no platform-specific code in proto. I'd report it as a gcc bug.

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com