[llvm] [AArch64] merge index address with large offset into base address (PR #72187)

[David Green via llvm-commits]

https://github.com/davemgreen commented:

It is probably best to split the CGP and DAG parts out into separate patches if we can. I'm seeing some failures in the test-suite, although the look like they might be post-isel so there might be something else going on. I'm still not 100% sure how to structure this without causing regressions in places.

https://github.com/llvm/llvm-project/pull/72187