Re: [dpdk-dev] [PATCH] lib/librte_sched: Fix compile with gcc 4.3.4

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> -----Original Message-----
> From: Qiu, Michael
> Sent: Friday, November 27, 2015 2:02 PM
> To: Ananyev, Konstantin
> Cc: Thomas Monjalon; dev@dpdk.org
> Subject: Re: [PATCH] lib/librte_sched: Fix compile with gcc 4.3.4
> 
> I just replied that Marco AVX only exist in gcc version < 4.4 , otherwise it will not exist.

If macro __AVX__ not defined, then 
#if defined(__AVX__)
would always be false and SCHED_VECTOR_ENABLE also wouldn't be defined.
So still don't understand why that is a problem
Konstantin

> 
> What's your suggest will not work if gcc version greater than 4.3.
> 
> So still need to check gcc version. Any other solution?
> 
> Thanks,
> Michael
> 
> > 在 2015年11月27日，下午8:34，Ananyev, Konstantin <konstantin.ananyev@intel.com> 写道：
> >
> >
> >> -----Original Message-----
> >> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Qiu, Michael
> >> Sent: Friday, November 27, 2015 11:53 AM
> >> To: Thomas Monjalon
> >> Cc: dev@dpdk.org
> >> Subject: Re: [dpdk-dev] [PATCH] lib/librte_sched: Fix compile with gcc 4.3.4
> >>
> >> really？I don't think so.
> >>
> >> AVX Marco only exist in the gcc version below 4.4,  I still need to check if below or beyond 4.4 am I right?
> >>
> >> Thanks,
> >> Michael
> >
> >
> > If you look at lib/librte_eal/common/include/arch/x86/rte_vect.h, you'll see the code similar
> > to one you are trying to put into rte_shed.c:
> >
> > lib/librte_eal/common/include/arch/x86/rte_vect.h:
> > ...
> > #if (defined(__ICC) || (__GNUC__ == 4 &&  __GNUC_MINOR__ < 4))
> >
> > #ifdef __SSE__
> > #include <xmmintrin.h>
> > #endif
> >
> > #ifdef __SSE2__
> > #include <emmintrin.h>
> > #endif
> >
> > #ifdef __SSE3__
> > #include <tmmintrin.h>
> > #endif
> >
> > #if defined(__SSE4_2__) || defined(__SSE4_1__)
> > #include <smmintrin.h>
> > #endif
> >
> > #if defined(__AVX__)
> > #include <immintrin.h>
> > #endif
> >
> > #else
> >
> > #include <x86intrin.h>
> >
> > #endif
> > ...
> >
> > So I think you can do just like that:
> >
> > #include <rte_vect.h>
> > #if defined(__AVX__)
> > #define SCHED_VECTOR_ENABLE
> > #endif
> >
> > inside rte_sched.c
> >
> > Konstantin
> >
> >
> >>
> >>
> >>> 在 2015年11月27日，下午5:01，Thomas Monjalon <thomas.monjalon@6wind.com> 写道：
> >>>
> >>> 2015-11-27 02:26, Qiu, Michael:
> >>>>>> On 2015/11/27 5:29, Thomas Monjalon wrote:
> >>>>>> 2015-11-26 18:49, Michael Qiu:
> >>>>>> gcc 4.3.4 does not include "immintrin.h", and will post below error:
> >>>>>>   lib/librte_sched/rte_sched.c:56:23: error:
> >>>>>>   immintrin.h: No such file or directory
> >>>>>>
> >>>>>> To avoid this issue, a gcc version check is need and a flag to indicate
> >>>>>> vector ablility.
> >>>>> [...]
> >>>>>> +#if (defined(__ICC) || (__GNUC__ == 4 &&  __GNUC_MINOR__ < 4))
> >>>>>> +
> >>>>>> +#if defined(__AVX__)
> >>>>>> #include <immintrin.h>
> >>>>>> +#define SCHED_VECTOR_ENABLE
> >>>>>> +#endif
> >>>>>> +
> >>>>>> +#else
> >>>>>> +
> >>>>>> +#include <x86intrin.h>
> >>>>>> +#define SCHED_VECTOR_ENABLE
> >>>>>> +
> >>>>>> +#endif
> >>>>> This kind of complication is managed by EAL.
> >>>>> I think we should include rte_vect.h.
> >>>>
> >>>> As I know here it needs a flag to identify whether the platform support
> >>>> AVX, if not it will not use it, so I don't know if we could only simply
> >>>> include rte_vect.h?
> >>>
> >>> It's not exclusive.
> >>> You can include rte_vect.h and check AVX to define SCHED_VECTOR_ENABLE.
> >>>