[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:

Removed `DAGCombiner::visitPtrAdd` from this PR, to be added with tests and a target use to a separate later PR. For now, the split changes live on the [`isd-ptradd-initial-dagcombine` branch in my fork](https://github.com/ritter-x2a/llvm-project/tree/isd-ptradd-initial-dagcombine).

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