On 2019-02-14 22:54 +0800, Colin Hercus wrote:
> Hi,
>
> I have several functions using SIMD intrinsics with target specific
> versions for SSE2, SSSE3, SSE4.1, AVX. They all use packed 8bit ints and
> only 128bit data.
>
> As I'm using intrinsics, each version target is slightly different, SSSE3
> has _mm_shuffle_epi8, SSE4.1 has _mm_blendv_epi8. Because I need to use
> only a few different intrinsics for each target the code is 95%
> triplicated. Luckily the AVX code can be a target_clone of the SSE4.1
> version but the others are slightly different.
>
> Is it possible to have code conditional on the target like #ifdef
> __TARGET_AVX2_
> that might let me have one source code with a few small conditional
> segments?
No. Because the preprocessor doesn't know what is "target attribute".
> I tried using #ifdef __AVX__ which works if I select an AVX target on the
> GCC command but doesn't work in a function with __attribute__ ((target
> ("avx")))
I suggest to compile one source file with -msse3, -mavx, -mavx2, etc. to get
multiple object files.
--
Xi Ruoyao <xry111@xxxxxxxxxxxxxxxx>
School of Aerospace Science and Technology, Xidian University
