[llvm] [DAGCombiner] Improve chain handling in fold (fshl ld1, ld0, c) -> (ld0[ofs]) combine. (PR #124871)

[Craig Topper via llvm-commits]

topperc wrote:

I haven't been able to get a test that shows a ordering problem. See the description.

I was able to test that we didn't do the transform previously if a store occurs after the loads.

https://github.com/llvm/llvm-project/pull/124871