[llvm] [PAC][llvm-readobj][AArch64][ELF] Support `GNU_PROPERTY_AARCH64_FEATURE_PAUTH` (PR #85231)

[Daniil Kovalev via llvm-commits]

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@@ -5098,6 +5098,86 @@ template <class ELFT> void GNUELFDumper<ELFT>::printAddrsig() {
   }
 }
 
+template <class ELFT>
+static bool printAArch64PAuthABICoreInfo(raw_ostream &OS, uint32_t DataSize,
+                                         ArrayRef<uint8_t> Desc) {
+  OS << "    AArch64 PAuth ABI core info: ";
+  // DataSize - size without padding, Desc.size() - size with padding
+  if (DataSize != 16) {
+    OS << format("<corrupted size: expected 16, got %d>", DataSize);
+    return false;
+  }
+
+  uint64_t Platform =
+      support::endian::read64<ELFT::TargetEndianness>(Desc.data() + 0);
+  uint64_t Version =
+      support::endian::read64<ELFT::TargetEndianness>(Desc.data() + 8);
+
+  std::string PlatformDesc = [Platform]() {
+    switch (Platform) {
+    case AARCH64_PAUTH_PLATFORM_INVALID:
+      return "invalid";
+    case AARCH64_PAUTH_PLATFORM_BAREMETAL:
+      return "baremetal";
+    case AARCH64_PAUTH_PLATFORM_LLVM_LINUX:
+      return "llvm_linux";
+    default:
+      return "unknown";
+    }
+  }();
+
+  std::string VersionDesc = [Platform, Version]() -> std::string {
+    if (Platform != AARCH64_PAUTH_PLATFORM_LLVM_LINUX)
+      return "";
+    if (Version >= (1 << (AARCH64_PAUTH_PLATFORM_LLVM_LINUX_VERSION_LAST + 1)))
+      return "unknown";
+    return std::string("") +
----------------
kovdan01 wrote:

Thanks for suggestion. I've switched to a slightly different approach. I've defined an array of flag names and then iterate over them in a loop and test each flag in the loop. Keeping in mind that we always have all flag names in the description and just add '!' for those which are disabled, it looks more clear.

See 8b562626454a9f6f9f9e41b8f84e17535924104d

https://github.com/llvm/llvm-project/pull/85231