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

[Alexander Richardson via llvm-commits]

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@@ -1729,6 +1734,10 @@ inline bool isExtVecInRegOpcode(unsigned Opcode) {
          Opcode == ISD::SIGN_EXTEND_VECTOR_INREG;
 }
 
+inline bool isPtrAdd(unsigned Opcode) {
+  return (Opcode == ISD::ADD) || (Opcode == ISD::PTRADD);
+}
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arichardson wrote:

Yes that would be good. I also wonder if the name `isAddition`/`isAnyAdd` would work better since every ISD::PTRADD is an addition, but with `isPtrAdd`, not every ISD::ADD is a ptradd?

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