release/20.x: [ORC] Switch to singleton pattern for UnwindInfoManager. (#126691)

llvm/include/llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h

@@ -90,10 +90,6 @@ using SPSRunAsIntFunctionSignature = int32_t(shared::SPSExecutorAddr, int32_t);
 } // end namespace rt
 
 namespace rt_alt {
-extern const char *UnwindInfoManagerInstanceName;
-extern const char *UnwindInfoManagerFindSectionsHelperName;
-extern const char *UnwindInfoManagerEnableWrapperName;
-extern const char *UnwindInfoManagerDisableWrapperName;
 extern const char *UnwindInfoManagerRegisterActionName;
 extern const char *UnwindInfoManagerDeregisterActionName;
 } // end namespace rt_alt

llvm/include/llvm/ExecutionEngine/Orc/TargetProcess/UnwindInfoManager.h

@@ -15,14 +15,13 @@
 #define LLVM_EXECUTIONENGINE_ORC_TARGETPROCESS_UNWINDINFOMANAGER_H
 
 #include "llvm/ExecutionEngine/Orc/Shared/ExecutorAddress.h"
-#include "llvm/ExecutionEngine/Orc/TargetProcess/ExecutorBootstrapService.h"
 #include "llvm/Support/Error.h"
 #include <map>
 #include <mutex>
 
 namespace llvm::orc {
 
-class UnwindInfoManager : public ExecutorBootstrapService {
+class UnwindInfoManager {
 public:
   // This struct's layout should match the unw_dynamic_unwind_sections struct
   // from libunwind/src/libunwid_ext.h.
@@ -34,43 +33,40 @@ class UnwindInfoManager : public ExecutorBootstrapService {
     size_t compact_unwind_section_length;
   };
 
+  UnwindInfoManager(UnwindInfoManager &&) = delete;
+  UnwindInfoManager &operator=(UnwindInfoManager &&) = delete;
+  ~UnwindInfoManager();
+
   /// If the libunwind find-dynamic-unwind-info callback registration APIs are
-  /// available then this method will return an UnwindInfoManager instance,
-  /// otherwise it will return nullptr.
-  static std::unique_ptr<UnwindInfoManager> TryCreate();
+  /// available then this method will instantiate a global UnwindInfoManager
+  /// instance suitable for the process and return true. Otherwise it will
+  /// return false.
+  static bool TryEnable();
 
-  Error shutdown() override;
-  void addBootstrapSymbols(StringMap<ExecutorAddr> &M) override;
+  static void addBootstrapSymbols(StringMap<ExecutorAddr> &M);
 
-  Error enable(void *FindDynamicUnwindSections);
-  Error disable(void);
+  static Error registerSections(ArrayRef<orc::ExecutorAddrRange> CodeRanges,
+                                orc::ExecutorAddr DSOBase,
+                                orc::ExecutorAddrRange DWARFEHFrame,
+                                orc::ExecutorAddrRange CompactUnwind);
 
-  Error registerSections(ArrayRef<orc::ExecutorAddrRange> CodeRanges,
-                         orc::ExecutorAddr DSOBase,
-                         orc::ExecutorAddrRange DWARFEHFrame,
-                         orc::ExecutorAddrRange CompactUnwind);
+  static Error deregisterSections(ArrayRef<orc::ExecutorAddrRange> CodeRanges);
 
-  Error deregisterSections(ArrayRef<orc::ExecutorAddrRange> CodeRanges);
+private:
+  UnwindInfoManager() = default;
 
-  int findSections(uintptr_t Addr, UnwindSections *Info);
+  int findSectionsImpl(uintptr_t Addr, UnwindSections *Info);
+  static int findSections(uintptr_t Addr, UnwindSections *Info);
 
-private:
-  UnwindInfoManager(int (*AddFindDynamicUnwindSections)(void *),
-                    int (*RemoveFindDynamicUnwindSections)(void *))
-      : AddFindDynamicUnwindSections(AddFindDynamicUnwindSections),
-        RemoveFindDynamicUnwindSections(RemoveFindDynamicUnwindSections) {}
+  Error registerSectionsImpl(ArrayRef<orc::ExecutorAddrRange> CodeRanges,
+                             orc::ExecutorAddr DSOBase,
+                             orc::ExecutorAddrRange DWARFEHFrame,
+                             orc::ExecutorAddrRange CompactUnwind);
 
-  static int findSectionsHelper(UnwindInfoManager *Instance, uintptr_t Addr,
-                                UnwindSections *Info);
+  Error deregisterSectionsImpl(ArrayRef<orc::ExecutorAddrRange> CodeRanges);
 
   std::mutex M;
   std::map<uintptr_t, UnwindSections> UWSecs;
-
-  int (*AddFindDynamicUnwindSections)(void *) = nullptr;
-  int (*RemoveFindDynamicUnwindSections)(void *) = nullptr;
-  void *FindDynamicUnwindSections = nullptr;
-
-  static const char *AddFnName, *RemoveFnName;
 };
 
 } // namespace llvm::orc

llvm/include/llvm/ExecutionEngine/Orc/UnwindInfoRegistrationPlugin.h

@@ -19,15 +19,17 @@ namespace llvm::orc {
 
 class UnwindInfoRegistrationPlugin : public LinkGraphLinkingLayer::Plugin {
 public:
-  static Expected<std::shared_ptr<UnwindInfoRegistrationPlugin>>
-  Create(IRLayer &IRL, JITDylib &PlatformJD, ExecutorAddr Instance,
-         ExecutorAddr FindHelper, ExecutorAddr Enable, ExecutorAddr Disable,
-         ExecutorAddr Register, ExecutorAddr Deregister);
+  UnwindInfoRegistrationPlugin(ExecutionSession &ES, ExecutorAddr Register,
+                               ExecutorAddr Deregister)
+      : ES(ES), Register(Register), Deregister(Deregister) {
+    DSOBaseName = ES.intern("__jitlink$libunwind_dso_base");
+  }
 
   static Expected<std::shared_ptr<UnwindInfoRegistrationPlugin>>
-  Create(IRLayer &IRL, JITDylib &PlatformJD);
+  Create(ExecutionSession &ES, ExecutorAddr Register, ExecutorAddr Deregister);
 
-  ~UnwindInfoRegistrationPlugin();
+  static Expected<std::shared_ptr<UnwindInfoRegistrationPlugin>>
+  Create(ExecutionSession &ES);
 
   void modifyPassConfig(MaterializationResponsibility &MR,
                         jitlink::LinkGraph &G,
@@ -49,20 +51,11 @@ class UnwindInfoRegistrationPlugin : public LinkGraphLinkingLayer::Plugin {
                                    ResourceKey SrcKey) override {}
 
 private:
-  UnwindInfoRegistrationPlugin(ExecutionSession &ES, ExecutorAddr Instance,
-                               ExecutorAddr Disable, ExecutorAddr Register,
-                               ExecutorAddr Deregister)
-      : ES(ES), Instance(Instance), Disable(Disable), Register(Register),
-        Deregister(Deregister) {
-    DSOBaseName = ES.intern("__jitlink$libunwind_dso_base");
-  }
-
-  static Expected<ThreadSafeModule> makeBouncerModule(ExecutionSession &ES);
   Error addUnwindInfoRegistrationActions(jitlink::LinkGraph &G);
 
   ExecutionSession &ES;
   SymbolStringPtr DSOBaseName;
-  ExecutorAddr Instance, Disable, Register, Deregister;
+  ExecutorAddr Register, Deregister;
 };
 
 } // namespace llvm::orc

llvm/lib/ExecutionEngine/Orc/ExecutorProcessControl.cpp

@@ -54,9 +54,8 @@ SelfExecutorProcessControl::SelfExecutorProcessControl(
   // FIXME: Don't add an UnwindInfoManager by default -- it's redundant when
   //        the ORC runtime is loaded. We'll need a way to document this and
   //        allow clients to choose.
-  this->UnwindInfoMgr = UnwindInfoManager::TryCreate();
-  if (this->UnwindInfoMgr)
-    this->UnwindInfoMgr->addBootstrapSymbols(this->BootstrapSymbols);
+  if (UnwindInfoManager::TryEnable())
+    UnwindInfoManager::addBootstrapSymbols(this->BootstrapSymbols);
 #endif // __APPLE__
 }
 

llvm/lib/ExecutionEngine/Orc/LLJIT.cpp

@@ -1241,8 +1241,8 @@ Expected<JITDylibSP> setUpGenericLLVMIRPlatform(LLJIT &J) {
 
       // If UseEHFrames hasn't been set then we're good to use compact-unwind.
       if (!UseEHFrames) {
-        if (auto UIRP = UnwindInfoRegistrationPlugin::Create(
-                J.getIRCompileLayer(), PlatformJD)) {
+        if (auto UIRP =
+                UnwindInfoRegistrationPlugin::Create(J.getExecutionSession())) {
           OLL->addPlugin(std::move(*UIRP));
           LLVM_DEBUG(dbgs() << "Enabled compact-unwind support.\n");
         } else

llvm/lib/ExecutionEngine/Orc/Shared/OrcRTBridge.cpp

@@ -65,14 +65,6 @@ const char *RunAsIntFunctionWrapperName =
 
 } // end namespace rt
 namespace rt_alt {
-const char *UnwindInfoManagerInstanceName =
-    "orc_rt_alt_UnwindInfoManager_Instance";
-const char *UnwindInfoManagerFindSectionsHelperName =
-    "orc_rt_alt_UnwindInfoManager_findSectionsHelper";
-const char *UnwindInfoManagerEnableWrapperName =
-    "orc_rt_alt_UnwindInfoManager_enable";
-const char *UnwindInfoManagerDisableWrapperName =
-    "orc_rt_alt_UnwindInfoManager_disable";
 const char *UnwindInfoManagerRegisterActionName =
     "orc_rt_alt_UnwindInfoManager_register";
 const char *UnwindInfoManagerDeregisterActionName =