[llvm] [AMDGPU][SDAG] Handle ISD::PTRADD in various special cases (PR #145330)

[Fabian Ritter via llvm-commits]

ritter-x2a wrote:

RE: buildbot failure at https://lab.llvm.org/buildbot/#/builders/186/builds/12525
I don't find anything in the logs indicating what (if anything) failed. It seems unlikely that this AMDGPU change would affect anything specifically in an x86-64/android build.

https://github.com/llvm/llvm-project/pull/145330