[llvm] [Inline][WinEH] Fix try scopes leaking to caller on inline (PR #164170)

[via llvm-commits]

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@@ -2210,6 +2211,135 @@ inlineRetainOrClaimRVCalls(CallBase &CB, objcarc::ARCInstKind RVCallKind,
   }
 }
 
+// Determine SEH try scopes and order them by dominance.
+static SmallVector<llvm::InvokeInst *, 1>
+GetOrderedSehTryScopes(Function *Func, DominatorTree &DT) {
+  SmallVector<llvm::InvokeInst *, 1> Scopes{};
+  bool DTCalculated = false;
+
+  for (auto &BB : *Func) {
+    auto *TI = BB.getTerminator();
+    if (auto *II = dyn_cast<InvokeInst>(TI)) {
+      auto *Call = cast<CallBase>(II);
+      const auto *Fn = Call->getCalledFunction();
+      if (!Fn || !Fn->isIntrinsic())
+        continue;
+
+      if (Fn->getIntrinsicID() != Intrinsic::seh_try_begin)
+        continue;
+
+      if (!DTCalculated) {
+        DT.recalculate(*Func);
+        DTCalculated = true;
+      }
+
+      auto InsertIt = Scopes.end();
+      if (!Scopes.empty())
+        for (auto ScopeIt = Scopes.begin(); ScopeIt != Scopes.end(); ++ScopeIt)
+          if (DT.dominates((*ScopeIt)->getParent(), &BB))
+            InsertIt = std::next(ScopeIt);
+
+      Scopes.insert(InsertIt, II);
+    }
+  }
+
+  return Scopes;
+}
+
+// Find, if present, the outermost unterminated try scope for the input block.
+static llvm::InvokeInst *GetOutermostUnterminatedTryScopeBegin(
+    llvm::BasicBlock *ReturnBlock, SmallVector<llvm::InvokeInst *, 1> &Scopes,
+    DominatorTree &DT) {
+  llvm::InvokeInst *UnterminatedScope{nullptr};
+
+  for (auto ScopeIt = Scopes.rbegin(); ScopeIt != Scopes.rend(); ++ScopeIt) {
+    auto *Invoke = *ScopeIt;
+
+    // Return might not be in a try scope.
+    if (!DT.dominates(Invoke->getParent(), ReturnBlock))
+      continue;
+
+    // If there is a catch which connects to the return, the try scope is
+    // considered to be terminated.
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MuellerMP wrote:

seh.try.end invokes are now also integrated if they exist.
I also added a seh specific test which on one hand makes sure that we find the seh.try.end terminator and on the other hand also asserts a correct termination for seh.try.begin invokes for a inlined callee with non cxx personality.

https://github.com/llvm/llvm-project/pull/164170