[llvm] [DebugInfo][InstCombine] Do not overwrite prior DILocation for new Insts (PR #108565)

[Paul T Robinson via llvm-commits]

pogo59 wrote:

> However even with this patch, if either of the load instructions has no DILocation, then the new load won't have one either,

If we merge locations on two instructions, but only one has a location, the merged result is no location? 

How often do we get a load with no DILocation in practice? It seems like that would be unusual.

https://github.com/llvm/llvm-project/pull/108565