[clang] [llvm] [RFC][BPF] Do atomic_fetch_*() pattern matching with memory ordering (PR #107343)

[via cfe-commits]

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@@ -91,6 +91,12 @@ void BTFTypeDerived::completeType(BTFDebug &BDebug) {
 
   // The base type for PTR/CONST/VOLATILE could be void.
   const DIType *ResolvedType = DTy->getBaseType();
+  if (ResolvedType) {
+    const auto *DerivedTy = dyn_cast<DIDerivedType>(ResolvedType);
+    if (DerivedTy && DerivedTy->getTag() == dwarf::DW_TAG_atomic_type)
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eddyz87 wrote:

Nit: since this is done in two places, maybe extract it as a utility?

https://github.com/llvm/llvm-project/pull/107343