Re: [dpdk-dev] [PATCH v3 0/3] AVX512 vPMD on i40e

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/20/2021 5:51 PM, Ferruh Yigit wrote:
> On 1/20/2021 10:05 AM, Ali Alnubani wrote:
>>>> For info, I don't reproduce the compilation issue on my machine.
>>>
>>> My build system has been upgraded from fc31 to fc32 so I guess this has
>>> something to do with it.
>>>
>>
>> I can reproduce with (Fedora MinGW 9.2.1-6.fc32), but not with (Fedora MinGW 
>> 10.2.1-2.fc33).
>>
> 
> First of all, for the patch @Tal provided its link, the windows build and the 
> mingw build errors are different. And the windows build error should be already 
> fixed by a patch that squashed in next-net (https://patches.dpdk.org/patch/86804/).
> 
> 
> And for the mingw, I have same result with Ali, I can reproduce with (Fedora 
> MinGW 9.2.1-6.fc32).
> 
> But different from the CI, I am getting the error [1] for all following files:
> rte_random.c
> i40e_rxtx_vec_sse.c
> i40e_rxtx_vec_avx512.c
> i40e_rxtx_vec_avx2.c
> rte_ethdev.c
> 
> [1] Error: invalid register for .seh_savexmm
> 

Build log for above errors: https://pastebin.com/jD4jRVzL

> 
> There is a stackoverflow entry for it:
> https://stackoverflow.com/questions/43152633/invalid-register-for-seh-savexmm-in-cygwin 
> 
> 
> If I use '-fno-asynchronous-unwind-tables' as suggested there, the build works 
> fine.
> 
> So the problem may not be just 'i40e_rxtx_vec_avx512.c'.
> 
> 
> If I change the machine type from 'native' to 'corei7' [2], the build error 
> reduced to only 'i40e_rxtx_vec_avx512.c', so the problem seems happens when 
> avx512 is supported by CPU, in this case compiler seems has a defect.
> And since for 'i40e_rxtx_vec_avx512.c' the '-march=skylake-avx512' explicitly 
> set can cause the problem seen in all machines.
> 
> [2]
>   diff --git a/config/x86/cross-mingw b/config/x86/cross-mingw
>   index 4c15a7fa2e..7cee238add 100644
>   --- a/config/x86/cross-mingw
>   +++ b/config/x86/cross-mingw
>   @@ -9,5 +9,5 @@ pkgconfig = 'x86_64-w64-mingw32-pkg-config'
>    [host_machine]
>    system = 'windows'
>    cpu_family = 'x86_64'
>   -cpu = 'native'
>   +cpu = 'corei7'
>    endian = 'little'
> 
> 
> 
> @Ranjit, @Pallavi,
> Are you building using mingw, and if so are you observing same problem?