[ExecutionEngine] Make RuntimeDyld::MemoryManager responsible for tracking EH

frames.

RuntimeDyld was previously responsible for tracking allocated EH frames, but it
makes more sense to have the RuntimeDyld::MemoryManager track them (since the
frames are allocated through the memory manager, and written to memory owned by
the memory manager). This patch moves the frame tracking into
RTDyldMemoryManager, and changes the deregisterFrames method on
RuntimeDyld::MemoryManager from:

void deregisterEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size);

to:

void deregisterEHFrames();

Separating this responsibility will allow ORC to continue to throw the
RuntimeDyld instances away post-link (saving a few dozen bytes per lazy
function) while properly deregistering frames when modules are unloaded.

This patch also updates ORC to call deregisterEHFrames when modules are
unloaded. This fixes a bug where an exception that tears down the JIT can then
unwind through dangling EH frames that have been deallocated but not
deregistered, resulting in UB.

For people using SectionMemoryManager this should be pretty much a no-op. For
people with custom allocators that override registerEHFrames/deregisterEHFrames,
you will now be responsible for tracking allocated EH frames.

Reviewed in https://reviews.llvm.org/D32829

llvm-svn: 302589

9 files changed, 18 insertions, 24 deletions

diff --git a/llvm/lib/ExecutionEngine/Orc/OrcMCJITReplacement.h b/llvm/lib/ExecutionEngine/Orc/OrcMCJITReplacement.h
index a5100a56bcf..a27573f93b9 100644
--- a/llvm/lib/ExecutionEngine/Orc/OrcMCJITReplacement.h
+++ b/llvm/lib/ExecutionEngine/Orc/OrcMCJITReplacement.h
@@ -94,9 +94,8 @@ class OrcMCJITReplacement : public ExecutionEngine {
       return ClientMM->registerEHFrames(Addr, LoadAddr, Size);
     }
 
-    void deregisterEHFrames(uint8_t *Addr, uint64_t LoadAddr,
-                            size_t Size) override {
-      return ClientMM->deregisterEHFrames(Addr, LoadAddr, Size);
+    void deregisterEHFrames() override {
+      return ClientMM->deregisterEHFrames();
     }
 
     void notifyObjectLoaded(RuntimeDyld &RTDyld,
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp
index de73fbde8eb..99e84b7496d 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RTDyldMemoryManager.cpp
@@ -134,6 +134,18 @@ void RTDyldMemoryManager::deregisterEHFramesInProcess(uint8_t *Addr,
 
 #endif
 
+void RTDyldMemoryManager::registerEHFrames(uint8_t *Addr, uint64_t LoadAddr,
+                                          size_t Size) {
+  registerEHFramesInProcess(Addr, Size);
+  EHFrames.push_back({Addr, Size});
+}
+
+void RTDyldMemoryManager::deregisterEHFrames() {
+  for (auto &Frame : EHFrames)
+    deregisterEHFramesInProcess(Frame.Addr, Frame.Size);
+  EHFrames.clear();
+}
+
 static int jit_noop() {
   return 0;
 }
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index df9d2ceba32..e9a4b71c903 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -73,7 +73,9 @@ namespace llvm {
 
 void RuntimeDyldImpl::registerEHFrames() {}
 
-void RuntimeDyldImpl::deregisterEHFrames() {}
+void RuntimeDyldImpl::deregisterEHFrames() {
+  MemMgr.deregisterEHFrames();
+}
 
 #ifndef NDEBUG
 static void dumpSectionMemory(const SectionEntry &S, StringRef State) {
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
index 2725d8ad0e7..660843765b3 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -221,22 +221,10 @@ void RuntimeDyldELF::registerEHFrames() {
     uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
     size_t EHFrameSize = Sections[EHFrameSID].getSize();
     MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
-    RegisteredEHFrameSections.push_back(EHFrameSID);
   }
   UnregisteredEHFrameSections.clear();
 }
 
-void RuntimeDyldELF::deregisterEHFrames() {
-  for (int i = 0, e = RegisteredEHFrameSections.size(); i != e; ++i) {
-    SID EHFrameSID = RegisteredEHFrameSections[i];
-    uint8_t *EHFrameAddr = Sections[EHFrameSID].getAddress();
-    uint64_t EHFrameLoadAddr = Sections[EHFrameSID].getLoadAddress();
-    size_t EHFrameSize = Sections[EHFrameSID].getSize();
-    MemMgr.deregisterEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
-  }
-  RegisteredEHFrameSections.clear();
-}
-
 std::unique_ptr<RuntimeDyldELF>
 llvm::RuntimeDyldELF::create(Triple::ArchType Arch,
                              RuntimeDyld::MemoryManager &MemMgr,
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
index 84dd810101f..fb5da6dd8bb 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
@@ -152,7 +152,6 @@ private:
   // in a table until we receive a request to register all unregistered
   // EH frame sections with the memory manager.
   SmallVector<SID, 2> UnregisteredEHFrameSections;
-  SmallVector<SID, 2> RegisteredEHFrameSections;
 
   // Map between GOT relocation value and corresponding GOT offset
   std::map<RelocationValueRef, uint64_t> GOTOffsetMap;
@@ -180,7 +179,6 @@ public:
                        StubMap &Stubs) override;
   bool isCompatibleFile(const object::ObjectFile &Obj) const override;
   void registerEHFrames() override;
-  void deregisterEHFrames() override;
   Error finalizeLoad(const ObjectFile &Obj,
                      ObjSectionToIDMap &SectionMap) override;
 };
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
index f5cc883d98f..18c23c5a2a5 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
@@ -515,7 +515,7 @@ public:
 
   virtual void registerEHFrames();
 
-  virtual void deregisterEHFrames();
+  void deregisterEHFrames();
 
   virtual Error finalizeLoad(const ObjectFile &ObjImg,
                              ObjSectionToIDMap &SectionMap) {
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFI386.h b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFI386.h
index 0398413e153..6aa1a2bdb92 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFI386.h
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFI386.h
@@ -217,7 +217,6 @@ public:
   }
 
   void registerEHFrames() override {}
-  void deregisterEHFrames() override {}
 };
 
 }
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFThumb.h b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFThumb.h
index 8c6af0bd9c6..318afa21a88 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFThumb.h
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFThumb.h
@@ -316,7 +316,6 @@ public:
   }
 
   void registerEHFrames() override {}
-  void deregisterEHFrames() override {}
 };
 
 }
diff --git a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h
index 109beb36f1e..26e73989d7e 100644
--- a/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h
+++ b/llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h
@@ -194,9 +194,6 @@ public:
     }
     UnregisteredEHFrameSections.clear();
   }
-  void deregisterEHFrames() override {
-    // Stub
-  }
   Error finalizeLoad(const ObjectFile &Obj,
                      ObjSectionToIDMap &SectionMap) override {
     // Look for and record the EH frame section IDs.