[llvm-branch-commits] [llvm] IR: Remove uselist for constantdata (PR #134692)

[Nikita Popov via llvm-branch-commits]

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@@ -889,10 +919,50 @@ inline raw_ostream &operator<<(raw_ostream &OS, const Value &V) {
   return OS;
 }
 
+inline Use::~Use() {
+  if (Val)
+    Val->removeUse(*this);
+}
+
+void Use::addToList(unsigned &Count) {
+  assert(isa<ConstantData>(Val) && "Only ConstantData is ref-counted");
+  ++Count;
+
+  // We don't have a uselist - clear the remnant if we are replacing a
+  // non-constant value.
+  Prev = nullptr;
+  Next = nullptr;
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nikic wrote:

Can you explain in more detail when this is necessary? It seems odd to me that addToList() should be responsible for nulling out these pointers.

https://github.com/llvm/llvm-project/pull/134692