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

[Matt Arsenault via llvm-commits]

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@@ -5641,7 +5641,8 @@ bool SelectionDAG::isADDLike(SDValue Op, bool NoWrap) const {
 
 bool SelectionDAG::isBaseWithConstantOffset(SDValue Op) const {
   return Op.getNumOperands() == 2 && isa<ConstantSDNode>(Op.getOperand(1)) &&
-         (Op.getOpcode() == ISD::ADD || isADDLike(Op));
+         (Op.getOpcode() == ISD::ADD || Op.getOpcode() == ISD::PTRADD ||
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arsenm wrote:

Probably should add an isPtrAdd helper for this add || ptradd pattern 

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