[llvm] [IR] Use alloc markers for operator delete variants (PR #138261)

[Daniel Paoliello via llvm-commits]

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@@ -54,21 +54,24 @@ class User : public Value {
   void *operator new(size_t Size) = delete;
 
   /// Indicates this User has operands "hung off" in another allocation.
-  struct HungOffOperandsAllocMarker {};
+  struct HungOffOperandsAllocMarker {
+    /// The number of operands for this User.
+    unsigned NumOps;
+  };
 
   /// Indicates this User has operands co-allocated.
   struct IntrusiveOperandsAllocMarker {
     /// The number of operands for this User.
-    const unsigned NumOps;
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dpaoliello wrote:

Why un-const these?

https://github.com/llvm/llvm-project/pull/138261