Re: Gnutools: consideration for upgrade to GCC 4.6

Bernard Fouché <[email protected]> Fri, 13 Jan 2012 19:54:28 +0100
Newsgroups gmane.os.ecos.devel
Message-ID <[email protected]>
Le 13/01/2012 18:00, Ilija Kocho a écrit :
>
> Our GCC 4.3.2 is ageing and perhaps we should consider an upgrade.
> My motive is it's lacking of support for Cortex-M4 SIMD (aka DSP) and 
> FPU instructions, but I think that other architectures shall gain from 
> newer compiler too. I have made some signal processing tests with GCC 
> 4.6.2 against current eCos compiler and they show performance gain 
> even with Cortex-M3 setting, though moderate. Performance is 
> considerable when Cortex-M4 setting is selected and is tremendous, as 
> expected, when SIMD are used. Recently introduced Cortex-M products 
> with FPU (Kinetis K70, K61, STM32F4) will further emphasise the benefit.
>
That sounds good! Did you try link time optimization ? I'm curious what 
kind of gain it could bring with a real world app. eCos seems to fit 
perfectly for such an optimization, there is no shared lib and at link 
time everythink is visible to the linker.