AVX2/512: Surprising return types and parameter types

​Hi,

​while working with AVX-2 and -512, we noticed the following discrepancies:

1) Why does _mm256_i64gather_epi64 return an __m128i according to the documentation? We would expect an __m256i. Dash agrees.

2) Why is the AVX-512 stream load interface different from AVX2?​

extern __m256i _mm256_stream_load_si256(__m256i const *);
extern __m512i _mm512_stream_load_si512(void * mem_addr);

​Especially the missing constness is a problem (albeit minor) because it requires a const_cast that should be unnecessary.

​Thanks
Markus

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