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inigyoutoday at 11:03 AM1 replyview on HN

Isn't 64 bytes needed for AVX512, then?


Replies

b3orntoday at 11:30 AM

There are two types of load/store instructions, one type requires alignment (vmovdqa), the other can load unaligned data (vmovdqu), in the case of AVX-512 the required alignment is 64 bytes. I assume aligned loads and stores are faster/have lower latency. For SSE/AVX you can look up the alignment requirements in Intel's intrinsics guide [0].

[0] https://www.intel.com/content/www/us/en/docs/intrinsics-guid...