[llvm] [DAGCombiner][VP] Add DAGCombine for VP_MUL (PR #80105)

[Shao-Ce SUN via llvm-commits]

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@@ -4404,20 +4408,21 @@ SDValue DAGCombiner::visitMUL(SDNode *N) {
   if (N1IsConst && ConstValue1.isOne())
     return N0;
 
-  if (SDValue NewSel = foldBinOpIntoSelect(N))
-    return NewSel;
+  if (!IsVP)
+    if (SDValue NewSel = foldBinOpIntoSelect(N))
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sunshaoce wrote:

This is equivalent to no change because of `!IsVP` here.

https://github.com/llvm/llvm-project/pull/80105