[llvm] [LegalizeDAG] Freeze index when converting insert_elt/insert_subvector to load/store on stack. (PR #86850)

[Craig Topper via llvm-commits]

topperc wrote:

> It looks like the original issue was reported against aarch64; should there be an aarch64 testcase?

Test added

https://github.com/llvm/llvm-project/pull/86850