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

[Fabian Ritter via llvm-commits]

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@@ -9138,8 +9138,8 @@ bool SelectionDAGBuilder::visitMemPCpyCall(const CallInst &I) {
   Size = DAG.getSExtOrTrunc(Size, sdl, Dst.getValueType());
 
   // Adjust return pointer to point just past the last dst byte.
-  SDValue DstPlusSize = DAG.getNode(ISD::ADD, sdl, Dst.getValueType(),
-                                    Dst, Size);
+  SDNodeFlags Flags;
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ritter-x2a wrote:

Indeed, I've now removed the unnecessary explicit argument setting here, thanks! I think we could actually use NUW here since this operation computes the position one-past-the-end of a memcpy'd memory range (which should either be within or one-past-the-end of an allocated object, which may not wrap according to the IR LangRef), but let's not add more functionality changes to this PR.

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