[llvm] [InstCombine] Lower multi-dimensional GEP to ptradd (PR #150383)

[Usha Gupta via llvm-commits]

usha1830 wrote:

> I think this change is going to have a very big impact on other transforms and will require lots of mitigation before it's viable. Especially after #137297 this is going to convert _all_ GEPs into ptradd representation.

This patch helps in fixing the regression seen in this issue  https://github.com/llvm/llvm-project/issues/143219. 
And yes, I see a lot of test failures and am looking into addressing those. 




https://github.com/llvm/llvm-project/pull/150383