[llvm] [BOLT][AArch64] Support for pointer authentication (PR #117578)

[Paschalis Mpeis via llvm-commits]

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@@ -0,0 +1,241 @@
+#include "bolt/Passes/InsertNegateRAStatePass.h"
+#include "bolt/Core/BinaryFunction.h"
+#include "bolt/Core/ParallelUtilities.h"
+#include "bolt/Utils/CommandLineOpts.h"
+#include <cstdlib>
+#include <fstream>
+#include <iterator>
+
+using namespace llvm;
+
+namespace llvm {
+namespace bolt {
+
+void InsertNegateRAState::runOnFunction(BinaryFunction &BF) {
+  BinaryContext &BC = BF.getBinaryContext();
+
+  if (BF.getState() == BinaryFunction::State::Empty) {
+    return;
+  }
+
+  if (BF.getState() != BinaryFunction::State::CFG &&
+      BF.getState() != BinaryFunction::State::CFG_Finalized) {
+    BC.outs() << "BOLT-INFO: No CFG for " << BF.getPrintName()
+              << " in InsertNegateRAStatePass\n";
+    return;
+  }
+
+  if (BF.isIgnored())
+    return;
+
+  if (!addNegateRAStateAfterPacOrAuth(BF)) {
+    // none inserted, function doesn't need more work
+    return;
+  }
+
+  auto FirstBB = BF.begin();
+  explore_call_graph(BC, &(*FirstBB));
+
+  // We have to do the walk again, starting from any undiscovered autiasp
+  // instructions, because some autiasp might not be reachable because of
+  // indirect branches but we know that autiasp block should have a Signed
+  // state, so we can work out other Unkown states starting from these nodes.
+  for (BinaryBasicBlock &BB : BF) {
+    if (BBhasAUTH(BC, &BB) && BB.isRAStateUnknown()) {
+      BB.setRASigned();
+      explore_call_graph(BC, &BB);
+    }
+  }
+
+  // insert negateRAState-s where there is a State boundary:
----------------
paschalis-mpeis wrote:

nit: minor changes like starting with a capital and ending with a dot.
(may applicable to more comments)

eg:
```
  // Insert negateRAStates where there is a State boundary.
  // That is two consecutive BBs have different RA State.
```

https://github.com/llvm/llvm-project/pull/117578