[llvm] [CodeGen] Refactor and document ThunkInserter (PR #97468)

[Kristof Beyls via llvm-commits]

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@@ -183,15 +183,13 @@ static const struct ThunkNameAndReg {
 namespace {
 struct SLSBLRThunkInserter : ThunkInserter<SLSBLRThunkInserter> {
   const char *getThunkPrefix() { return SLSBLRNamePrefix; }
-  bool mayUseThunk(const MachineFunction &MF, bool InsertedThunks) {
-    if (InsertedThunks)
-      return false;
+  bool mayUseThunk(const MachineFunction &MF) {
+    // FIXME: ComdatThunks is only accumulated until the first thunk is created.
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kbeyls wrote:

I don't fully understand this FIXME very well. Could you explain this in a bit more detail?


https://github.com/llvm/llvm-project/pull/97468