[Lldb-commits] [lldb] [lldb] Support PtrAuth in the expression evaluator (PR #186001)

[Jonas Devlieghere via lldb-commits]

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@@ -0,0 +1,180 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "InjectPointerSigningFixups.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/TargetParser/Triple.h"
+
+using namespace llvm;
+
+namespace {
+struct PtrAuthFixup {
+  GlobalVariable *GV;
+  ConstantPtrAuth *CPA;
+  SmallVector<unsigned> Indices;
+};
+} // namespace
+
+/// Recursively walk a constant looking for ConstantPtrAuth expressions.
+/// When found, record the global variable containing the ConstantPtrAuth and
+/// the index path to reach it within the initializer.
+static void findPtrAuth(Constant *C, GlobalVariable &GV,
+                        SmallVector<unsigned> &Indices,
+                        SmallVectorImpl<PtrAuthFixup> &Fixups) {
+  if (auto *CPA = dyn_cast<ConstantPtrAuth>(C)) {
+    Fixups.push_back({&GV, CPA, Indices});
+    return;
+  }
+  for (unsigned I = 0, E = C->getNumOperands(); I != E; ++I) {
+    if (auto *COp = dyn_cast<Constant>(C->getOperand(I))) {
+      Indices.push_back(I);
+      findPtrAuth(COp, GV, Indices, Fixups);
+      Indices.pop_back();
+    }
+  }
+}
+
+namespace lldb_private {
+
----------------
JDevlieghere wrote:

Done, let me know if you're happy with the wording and example. I also switched the name of the helper again as I think `arm64e` was a bit too opaque.

https://github.com/llvm/llvm-project/pull/186001