[ORC] Update ELF debugger support plugin to use AllocActions

Author: weliveindetail

llvm/include/llvm/ExecutionEngine/Orc/DebugObjectManagerPlugin.h

@@ -15,8 +15,8 @@
 
 #include "llvm/ExecutionEngine/JITLink/JITLink.h"
 #include "llvm/ExecutionEngine/Orc/Core.h"
-#include "llvm/ExecutionEngine/Orc/EPCDebugObjectRegistrar.h"
 #include "llvm/ExecutionEngine/Orc/ObjectLinkingLayer.h"
+#include "llvm/ExecutionEngine/Orc/Shared/ExecutorAddress.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/Memory.h"
@@ -48,10 +48,6 @@ class DebugObject;
 ///
 class LLVM_ABI DebugObjectManagerPlugin : public ObjectLinkingLayer::Plugin {
 public:
-  // DEPRECATED - Please specify options explicitly
-  DebugObjectManagerPlugin(ExecutionSession &ES,
-                           std::unique_ptr<DebugObjectRegistrar> Target);
-
   /// Create the plugin to submit DebugObjects for JITLink artifacts. For all
   /// options the recommended setting is true.
   ///
@@ -67,16 +63,14 @@ class LLVM_ABI DebugObjectManagerPlugin : public ObjectLinkingLayer::Plugin {
   ///   sequence. When turning this off, the user has to issue the call to
   ///   __jit_debug_register_code() on the executor side manually.
   ///
-  DebugObjectManagerPlugin(ExecutionSession &ES,
-                           std::unique_ptr<DebugObjectRegistrar> Target,
-                           bool RequireDebugSections, bool AutoRegisterCode);
+  DebugObjectManagerPlugin(ExecutionSession &ES, bool RequireDebugSections,
+                           bool AutoRegisterCode, Error &Err);
   ~DebugObjectManagerPlugin() override;
 
   void notifyMaterializing(MaterializationResponsibility &MR,
                            jitlink::LinkGraph &G, jitlink::JITLinkContext &Ctx,
                            MemoryBufferRef InputObject) override;
 
-  Error notifyEmitted(MaterializationResponsibility &MR) override;
   Error notifyFailed(MaterializationResponsibility &MR) override;
   Error notifyRemovingResources(JITDylib &JD, ResourceKey K) override;
 
@@ -97,7 +91,7 @@ class LLVM_ABI DebugObjectManagerPlugin : public ObjectLinkingLayer::Plugin {
   std::mutex PendingObjsLock;
   std::mutex RegisteredObjsLock;
 
-  std::unique_ptr<DebugObjectRegistrar> Target;
+  ExecutorAddr RegistrationAction;
   bool RequireDebugSections;
   bool AutoRegisterCode;
 };

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

@@ -59,6 +59,8 @@ LLVM_ABI extern const char *MemoryReadStringsWrapperName;
 LLVM_ABI extern const char *RegisterEHFrameSectionAllocActionName;
 LLVM_ABI extern const char *DeregisterEHFrameSectionAllocActionName;
 
+LLVM_ABI extern const char *RegisterJITLoaderGDBAllocActionName;
+
 LLVM_ABI extern const char *RunAsMainWrapperName;
 LLVM_ABI extern const char *RunAsVoidFunctionWrapperName;
 LLVM_ABI extern const char *RunAsIntFunctionWrapperName;

llvm/lib/ExecutionEngine/Orc/DebugObjectManagerPlugin.cpp

@@ -19,6 +19,7 @@
 #include "llvm/BinaryFormat/ELF.h"
 #include "llvm/ExecutionEngine/JITLink/JITLinkDylib.h"
 #include "llvm/ExecutionEngine/JITLink/JITLinkMemoryManager.h"
+#include "llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h"
 #include "llvm/Object/ELFObjectFile.h"
 #include "llvm/Support/Errc.h"
 #include "llvm/Support/MSVCErrorWorkarounds.h"
@@ -115,7 +116,9 @@ class DebugObject {
 public:
   DebugObject(JITLinkMemoryManager &MemMgr, const JITLinkDylib *JD,
               ExecutionSession &ES)
-      : MemMgr(MemMgr), JD(JD), ES(ES), Flags(DebugObjectFlags{}) {}
+      : MemMgr(MemMgr), JD(JD), ES(ES), Flags(DebugObjectFlags{}) {
+    FinalizeFuture = FinalizePromise.get_future();
+  }
 
   bool hasFlags(DebugObjectFlags F) const { return Flags & F; }
   void setFlags(DebugObjectFlags F) {
@@ -126,8 +129,17 @@ class DebugObject {
   }
 
   using FinalizeContinuation = std::function<void(Expected<ExecutorAddrRange>)>;
+  void finalizeAsync(FinalizeContinuation OnAsync);
+
+  void failMaterialization(Error Err) {
+    FinalizePromise.set_value(std::move(Err));
+  }
 
-  void finalizeAsync(FinalizeContinuation OnFinalize);
+  void reportTargetMem(ExecutorAddrRange TargetMem) {
+    FinalizePromise.set_value(TargetMem);
+  }
+
+  Expected<ExecutorAddrRange> awaitTargetMem() { return FinalizeFuture.get(); }
 
   virtual ~DebugObject() {
     if (Alloc) {
@@ -151,6 +163,9 @@ class DebugObject {
   const JITLinkDylib *JD = nullptr;
   ExecutionSession &ES;
 
+  std::promise<MSVCPExpected<ExecutorAddrRange>> FinalizePromise;
+  std::future<MSVCPExpected<ExecutorAddrRange>> FinalizeFuture;
+
 private:
   DebugObjectFlags Flags;
   FinalizedAlloc Alloc;
@@ -160,22 +175,27 @@ class DebugObject {
 // copying memory over to the target and pass on the result once we're done.
 // Ownership of the allocation remains with us for the rest of our lifetime.
 void DebugObject::finalizeAsync(FinalizeContinuation OnFinalize) {
-  assert(!Alloc && "Cannot finalize more than once");
-
+  assert(!this->Alloc && "Cannot finalize more than once");
   if (auto SimpleSegAlloc = finalizeWorkingMemory()) {
     auto ROSeg = SimpleSegAlloc->getSegInfo(MemProt::Read);
     ExecutorAddrRange DebugObjRange(ROSeg.Addr, ROSeg.WorkingMem.size());
     SimpleSegAlloc->finalize(
         [this, DebugObjRange,
          OnFinalize = std::move(OnFinalize)](Expected<FinalizedAlloc> FA) {
           if (FA) {
-            Alloc = std::move(*FA);
+            // Note: FA->getAddress() is supposed to be the address of the
+            // memory range on the target, but InProcessMemoryManager returns
+            // the address of a FinalizedAllocInfo helper instead.
+            this->Alloc = std::move(*FA);
             OnFinalize(DebugObjRange);
           } else
             OnFinalize(FA.takeError());
         });
-  } else
+  } else {
+    // We could report this error synchronously, but it's easier this way,
+    // because the FinalizePromise will be triggered unconditionally.
     OnFinalize(SimpleSegAlloc.takeError());
+  }
 }
 
 /// The current implementation of ELFDebugObject replicates the approach used in
@@ -386,16 +406,17 @@ createDebugObjectFromBuffer(ExecutionSession &ES, LinkGraph &G,
   }
 }
 
-DebugObjectManagerPlugin::DebugObjectManagerPlugin(
-    ExecutionSession &ES, std::unique_ptr<DebugObjectRegistrar> Target,
-    bool RequireDebugSections, bool AutoRegisterCode)
-    : ES(ES), Target(std::move(Target)),
-      RequireDebugSections(RequireDebugSections),
-      AutoRegisterCode(AutoRegisterCode) {}
-
-DebugObjectManagerPlugin::DebugObjectManagerPlugin(
-    ExecutionSession &ES, std::unique_ptr<DebugObjectRegistrar> Target)
-    : DebugObjectManagerPlugin(ES, std::move(Target), true, true) {}
+DebugObjectManagerPlugin::DebugObjectManagerPlugin(ExecutionSession &ES,
+                                                   bool RequireDebugSections,
+                                                   bool AutoRegisterCode,
+                                                   Error &Err)
+    : ES(ES), RequireDebugSections(RequireDebugSections),
+      AutoRegisterCode(AutoRegisterCode) {
+  // Pass bootstrap symbol for registration function to enable debugging
+  ErrorAsOutParameter _(&Err);
+  Err = ES.getExecutorProcessControl().getBootstrapSymbols(
+      {{RegistrationAction, rt::RegisterJITLoaderGDBAllocActionName}});
+}
 
 DebugObjectManagerPlugin::~DebugObjectManagerPlugin() = default;
 
@@ -440,48 +461,50 @@ void DebugObjectManagerPlugin::modifyPassConfig(
                                                     SectionRange(GraphSection));
           return Error::success();
         });
-  }
-}
 
-Error DebugObjectManagerPlugin::notifyEmitted(
-    MaterializationResponsibility &MR) {
-  std::lock_guard<std::mutex> Lock(PendingObjsLock);
-  auto It = PendingObjs.find(&MR);
-  if (It == PendingObjs.end())
-    return Error::success();
-
-  // During finalization the debug object is registered with the target.
-  // Materialization must wait for this process to finish. Otherwise we might
-  // start running code before the debugger processed the corresponding debug
-  // info.
-  std::promise<MSVCPError> FinalizePromise;
-  std::future<MSVCPError> FinalizeErr = FinalizePromise.get_future();
-
-  It->second->finalizeAsync(
-      [this, &FinalizePromise, &MR](Expected<ExecutorAddrRange> TargetMem) {
-        // Any failure here will fail materialization.
-        if (!TargetMem) {
-          FinalizePromise.set_value(TargetMem.takeError());
-          return;
-        }
-        if (Error Err =
-                Target->registerDebugObject(*TargetMem, AutoRegisterCode)) {
-          FinalizePromise.set_value(std::move(Err));
-          return;
-        }
-
-        // Once our tracking info is updated, notifyEmitted() can return and
-        // finish materialization.
-        FinalizePromise.set_value(MR.withResourceKeyDo([&](ResourceKey K) {
-          assert(PendingObjs.count(&MR) && "We still hold PendingObjsLock");
-          std::lock_guard<std::mutex> Lock(RegisteredObjsLock);
-          auto It = PendingObjs.find(&MR);
-          RegisteredObjs[K].push_back(std::move(It->second));
-          PendingObjs.erase(It);
-        }));
-      });
-
-  return FinalizeErr.get();
+    PassConfig.PreFixupPasses.push_back(
+        [this, &DebugObj, &MR](LinkGraph &G) -> Error {
+          DebugObj.finalizeAsync([this, &DebugObj,
+                                  &MR](Expected<ExecutorAddrRange> TargetMem) {
+            if (!TargetMem) {
+              DebugObj.failMaterialization(TargetMem.takeError());
+              return;
+            }
+            // Update tracking info
+            Error Err = MR.withResourceKeyDo([&](ResourceKey K) {
+              std::lock_guard<std::mutex> LockPending(PendingObjsLock);
+              std::lock_guard<std::mutex> LockRegistered(RegisteredObjsLock);
+              auto It = PendingObjs.find(&MR);
+              RegisteredObjs[K].push_back(std::move(It->second));
+              PendingObjs.erase(It);
+            });
+
+            if (Err)
+              DebugObj.failMaterialization(std::move(Err));
+
+            // Unblock post-fixup pass
+            DebugObj.reportTargetMem(*TargetMem);
+          });
+          return Error::success();
+        });
+
+    PassConfig.PostFixupPasses.push_back(
+        [this, &DebugObj](LinkGraph &G) -> Error {
+          Expected<ExecutorAddrRange> R = DebugObj.awaitTargetMem();
+          if (!R)
+            return R.takeError();
+          if (R->empty())
+            return Error::success();
+
+          using namespace shared;
+          G.allocActions().push_back(
+              {cantFail(WrapperFunctionCall::Create<
+                        SPSArgList<SPSExecutorAddrRange, bool>>(
+                   RegistrationAction, *R, AutoRegisterCode)),
+               {/* no deregistration */}});
+          return Error::success();
+        });
+  }
 }
 
 Error DebugObjectManagerPlugin::notifyFailed(

llvm/lib/ExecutionEngine/Orc/Debugging/DebuggerSupport.cpp

@@ -35,12 +35,10 @@ Error enableDebuggerSupport(LLJIT &J) {
 
   switch (TT.getObjectFormat()) {
   case Triple::ELF: {
-    auto Registrar = createJITLoaderGDBRegistrar(ES);
-    if (!Registrar)
-      return Registrar.takeError();
+    Error TargetSymErr = Error::success();
     ObjLinkingLayer->addPlugin(std::make_unique<DebugObjectManagerPlugin>(
-        ES, std::move(*Registrar), false, true));
-    return Error::success();
+        ES, false, true, TargetSymErr));
+    return TargetSymErr;
   }
   case Triple::MachO: {
     auto DS = GDBJITDebugInfoRegistrationPlugin::Create(ES, *ProcessSymsJD, TT);

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

@@ -74,6 +74,9 @@ const char *RegisterEHFrameSectionAllocActionName =
 const char *DeregisterEHFrameSectionAllocActionName =
     "llvm_orc_deregisterEHFrameAllocAction";
 
+const char *RegisterJITLoaderGDBAllocActionName =
+    "llvm_orc_registerJITLoaderGDBAllocAction";
+
 const char *RunAsMainWrapperName = "__llvm_orc_bootstrap_run_as_main_wrapper";
 const char *RunAsVoidFunctionWrapperName =
     "__llvm_orc_bootstrap_run_as_void_function_wrapper";

llvm/lib/ExecutionEngine/Orc/TargetProcess/DefaultHostBootstrapValues.cpp

@@ -9,6 +9,7 @@
 #include "llvm/ExecutionEngine/Orc/TargetProcess/DefaultHostBootstrapValues.h"
 
 #include "llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h"
+#include "llvm/ExecutionEngine/Orc/TargetProcess/JITLoaderGDB.h"
 #include "llvm/ExecutionEngine/Orc/TargetProcess/RegisterEHFrames.h"
 
 #ifdef __APPLE__
@@ -27,6 +28,9 @@ void addDefaultBootstrapValuesForHostProcess(
   BootstrapSymbols[rt::DeregisterEHFrameSectionAllocActionName] =
       ExecutorAddr::fromPtr(&llvm_orc_deregisterEHFrameSectionAllocAction);
 
+  BootstrapSymbols[rt::RegisterJITLoaderGDBAllocActionName] =
+      ExecutorAddr::fromPtr(&llvm_orc_registerJITLoaderGDBAllocAction);
+
 #ifdef __APPLE__
   if (!dlsym(RTLD_DEFAULT, "__unw_add_find_dynamic_unwind_sections"))
     BootstrapMap["darwin-use-ehframes-only"].push_back(1);

llvm/lib/ExecutionEngine/Orc/TargetProcess/SimpleRemoteEPCServer.cpp

@@ -9,6 +9,7 @@
 #include "llvm/ExecutionEngine/Orc/TargetProcess/SimpleRemoteEPCServer.h"
 
 #include "llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h"
+#include "llvm/ExecutionEngine/Orc/TargetProcess/DefaultHostBootstrapValues.h"
 #include "llvm/ExecutionEngine/Orc/TargetProcess/RegisterEHFrames.h"
 #include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/Process.h"
@@ -206,10 +207,7 @@ Error SimpleRemoteEPCServer::sendSetupMessage(
          "Dispatch function name should not be set");
   EI.BootstrapSymbols[ExecutorSessionObjectName] = ExecutorAddr::fromPtr(this);
   EI.BootstrapSymbols[DispatchFnName] = ExecutorAddr::fromPtr(jitDispatchEntry);
-  EI.BootstrapSymbols[rt::RegisterEHFrameSectionAllocActionName] =
-      ExecutorAddr::fromPtr(&llvm_orc_registerEHFrameSectionAllocAction);
-  EI.BootstrapSymbols[rt::DeregisterEHFrameSectionAllocActionName] =
-      ExecutorAddr::fromPtr(&llvm_orc_deregisterEHFrameSectionAllocAction);
+  addDefaultBootstrapValuesForHostProcess(EI.BootstrapMap, EI.BootstrapSymbols);
 
   using SPSSerialize =
       shared::SPSArgList<shared::SPSSimpleRemoteEPCExecutorInfo>;

llvm/tools/llvm-jitlink/llvm-jitlink.cpp

@@ -1295,9 +1295,13 @@ Session::Session(std::unique_ptr<ExecutorProcessControl> EPC, Error &Err)
   } else if (TT.isOSBinFormatELF()) {
     if (!NoExec)
       ObjLayer.addPlugin(ExitOnErr(EHFrameRegistrationPlugin::Create(ES)));
-    if (DebuggerSupport)
+    if (DebuggerSupport) {
+      Error TargetSymErr = Error::success();
       ObjLayer.addPlugin(std::make_unique<DebugObjectManagerPlugin>(
-          ES, ExitOnErr(createJITLoaderGDBRegistrar(this->ES)), true, true));
+          ES, true, true, TargetSymErr));
+      logAllUnhandledErrors(std::move(TargetSymErr), errs(),
+                            "Debugger support not available: ");
+    }
   }
 
   if (auto MainJDOrErr = ES.createJITDylib("main"))