[llvm] [SelectionDAG] Introduce ISD::PTRADD (PR #140017)

[Fabian Ritter via llvm-commits]

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@@ -2617,6 +2620,85 @@ SDValue DAGCombiner::foldSubToAvg(SDNode *N, const SDLoc &DL) {
   return SDValue();
 }
 
+/// Try to fold a pointer arithmetic node.
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ritter-x2a wrote:

I could add a CLI option to enable PTRADD generation for AMDGPU (for bring-up only, to be removed such that PTRADDs are always used there once the regressions in all the other tests are resolved) and make a PR with the DAGCombine changes and AMDGPU tests that use that option. What do you think?

https://github.com/llvm/llvm-project/pull/140017