collapse's blog

By collapse, history, 3 years ago, In English

Does anyone know why __int128 seems to use 64-bit operations instead of SIMD instructions?

In this demo, 64-bit instructions are used but switching __int128 with any smaller type (int, long long, etc.) enables vectorization + unrolling.

Is using 64-bit operations just faster than loading into/out of the 128-bit registers?

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