[llvm] [AsmParser] Add support for reading incomplete IR (part 1) (PR #78421)

[Nikita Popov via llvm-commits]

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@@ -123,6 +130,57 @@ void LLParser::restoreParsingState(const SlotMapping *Slots) {
         std::make_pair(I.first, std::make_pair(I.second, LocTy())));
 }
 
+void LLParser::dropUnknownMetadataReferences() {
+  auto Pred = [](unsigned MDKind, MDNode *Node) { return Node->isTemporary(); };
+  for (Function &F : *M) {
+    F.eraseMetadataIf(Pred);
+    for (BasicBlock &BB : F) {
+      for (Instruction &I : make_early_inc_range(BB)) {
+        I.eraseMetadataIf(Pred);
+
+        if (auto *II = dyn_cast<IntrinsicInst>(&I)) {
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nikic wrote:

I've opted to move this logic into a separate function instead, so we can use early return.

https://github.com/llvm/llvm-project/pull/78421