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Test results for Broadwell and Skylake
Author:  Date: 2017-07-13 13:07
According to the following URL:
techreport.com/review/32111/intel-core-i9-7900x-cpu-reviewed-part-one

SKYLAKE-X is able to handle two 64-byte loads per cycle, so there is a chance the throughput of gather can be improved.

Not really, because it's still two loads, just the load width has been increased to 64B. The gather implementations are limited by the *number of loads*, and not by the width of the loads (indeed, even 32 bytes was already much wider than the largest gather elements of 8 byte).

Gather pretty much runs at 2 loads/cycle on the existing implementations, so unless you break that barrier (i.e., go to 3 load ports) you are very unlikely to see scatter perform better than that in the general case. What you might see first are optimizations for special cases of adjacent or overlapping elements, but that's more or less orthogonal to load width.
Xing Liu wrote:

 
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