[llvm] [SLP]Emit actual bitwidth for analyzed MinBitwidth nodes, NFCI. (PR #71536)

[Valery Dmitriev via llvm-commits]

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@@ -9034,6 +9079,28 @@ InstructionCost BoUpSLP::getTreeCost(ArrayRef<Value *> VectorizedVals) {
             FirstUsers.emplace_back(VU, ScalarTE);
             DemandedElts.push_back(APInt::getZero(FTy->getNumElements()));
             VecId = FirstUsers.size() - 1;
+            auto It = MinBWs.find(EU.Scalar);
+            if (It != MinBWs.end() && VectorCasts.insert(EU.Scalar).second) {
+              unsigned BWSz = It->second.second;
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valerydmit wrote:

It->second.first ? "second" is  a boolean value.

https://github.com/llvm/llvm-project/pull/71536