[llvm] [AArch64] Fix throughout of 64-bit SVE gather loads (PR #168572)

[Asher Dobrescu via llvm-commits]

Asher8118 wrote:

> why isn't it possible to get the correct throughput with the existing resources?

Because the pipeline used by gather loads is unit L, which has 3 resources. This makes it so the throughput is a result of a division by 3.

https://github.com/llvm/llvm-project/pull/168572