How to load usigned char to __m512i on KNL

[Zekun_Y_]

How can I load the unsigned char to a __m512i vector on KNL?

I can't find the similar instrinsic like extload(I use extload on KNC) on KNL. On the other hand the AVX512-BW is not supported on KNL as well, so I can't use  _mm512_mask_load_epi8 to load a uint8. Is there anyway could load the unsigned char efficiently to a __m512i?

Thank you

[andysem · Accepted solution]

I guess you can load 16 bytes into __m128i and then use _mm512_cvtepi8_epi32/_mm512_cvtepu8_epi32 to convert the bytes to 32-bit integers for processing. AVX-512F does not support operating on 8-bit integers directly.

[Zekun_Y_]

I just tested it. It seems working well.

Thank you very much!

andysem wrote:

I guess you can load 16 bytes into __m128i and then use _mm512_cvtepi8_epi32/_mm512_cvtepu8_epi32 to convert the bytes to 32-bit integers for processing. AVX-512F does not support operating on 8-bit integers directly.