[llvm] [DAGCombiner] Add combine avg from shifts (PR #113909)

[Simon Pilgrim via llvm-commits]

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@@ -11393,6 +11413,56 @@ static SDValue combineMinNumMaxNumImpl(const SDLoc &DL, EVT VT, SDValue LHS,
   }
 }
 
+SDValue DAGCombiner::combineAVG(SDNode *N) {
+  const auto Opcode = N->getOpcode();
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RKSimon wrote:

(style) Don't use auto

https://github.com/llvm/llvm-project/pull/113909