[clang] [llvm] [AArch64][SVE2.1] Add intrinsics for quadword loads/stores with unscaled offset (PR #70474)

[David Sherwood via llvm-commits]

https://github.com/david-arm approved this pull request.

LGTM. I think I would have preferred the patch to be split up into 3 - one for contiguous extending loads/truncating stores, one for structured loads/stores, and one for the gathers. That's why it took me so long to review this patch as I was constantly trying to keep all the information about each builtin/instruction in my head whilst reviewing the tests for correctness!

https://github.com/llvm/llvm-project/pull/70474