[llvm] [SLP] NFC. Replace TreeEntry::setOperandsInOrder with VLOperands. (PR #113880)

[Alexey Bataev via llvm-commits]

================
@@ -2366,7 +2363,10 @@ class BoUpSLP {
     }
 
     /// \returns the number of operands.
-    unsigned getNumOperands() const { return OpsVec.size(); }
+    /// reorder can only work on instructions with 2 operands. If we use
+    /// OpsVec.size() here, reorder will swap non-swappable operands (because
+    /// APO is a boolean value).
+    unsigned getNumOperands() const { return 2; }
----------------
alexey-bataev wrote:

I don't like this approach. I plan to extend the reordering to support many operands, better to avoid constant value here.

https://github.com/llvm/llvm-project/pull/113880