[llvm] [NVPTX] Improve folding to mad with immediate 1 (PR #93628)

[Artem Belevich via llvm-commits]

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@@ -5614,17 +5614,98 @@ static SDValue TryMULWIDECombine(SDNode *N,
   return DCI.DAG.getNode(Opc, DL, MulType, TruncLHS, TruncRHS);
 }
 
+static SDValue matchMADConstOnePattern(SDValue X, SDValue Add) {
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Artem-B wrote:

`X` is unused.

https://github.com/llvm/llvm-project/pull/93628