Developer Guide and Reference



Typecasts 128-bit integer values to 256-bit integer values. No corresponding Intel® AVX instruction.


extern __m256i _mm256_castsi128_si256(__m128i a);
128-bit integer source vector
Performs a typecast operation from 128-bit integer values to 256-bit integer values.
The lower 128-bits of the 256-bit resulting vector contains the source vector values; the upper 128-bits of the resulting vector are undefined. This intrinsic does not introduce extra moves to the generated code.
A vector with 256-bit integer values. The upper bits of the resulting vector are undefined.

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Notice revision #20110804