[llvm] [SLP]Initial FMAD support (PR #149102)

[Simon Pilgrim via llvm-commits]

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@@ -13587,6 +13688,12 @@ BoUpSLP::getEntryCost(const TreeEntry *E, ArrayRef<Value *> VectorizedVals,
     }
     return IntrinsicCost;
   };
+  auto GetFMulAddCost = [&, &TTI = *TTI](const InstructionsState &S,
+                                         Instruction *VI = nullptr) {
+    InstructionCost Cost = canConvertToFMA(VI ? ArrayRef<Value *>(VI) : VL, S,
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RKSimon wrote:

where can VI be null? All calls appear to have 2 args, is the default value necessary?

https://github.com/llvm/llvm-project/pull/149102