[llvm] [SLP] Let the caller tell canConvertToFMA which operand holds the fmul (PR #218754)

[Alexey Bataev via llvm-commits]

================
@@ -16694,9 +16698,11 @@ BoUpSLP::getEntryCost(const TreeEntry *E, ArrayRef<Value *> VectorizedVals,
       InstructionCost ScalarCost = TTI->getArithmeticInstrCost(
           ShuffleOrOp, OrigScalarTy, CostKind, Op1Info, Op2Info, Operands);
       if (auto *I = dyn_cast<Instruction>(UniqueValues[Idx]);
-          I && (ShuffleOrOp == Instruction::FAdd ||
-                ShuffleOrOp == Instruction::FSub)) {
-        InstructionCost IntrinsicCost = GetFMulAddCost(E->getOperations(), I);
+          I && !E->isCopyableElement(I) &&
----------------
alexey-bataev wrote:

Why copyables are excluded?

https://github.com/llvm/llvm-project/pull/218754