3 files changed, 763 insertions, 0 deletions
diff --git a/contrib/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/contrib/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
new file mode 100644
index 0000000..38aa547
--- /dev/null
+++ b/contrib/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -0,0 +1,377 @@
+//===-- MCJIT.cpp - MC-based Just-in-Time Compiler ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MCJIT.h"
+#include "llvm/ExecutionEngine/GenericValue.h"
+#include "llvm/ExecutionEngine/JITEventListener.h"
+#include "llvm/ExecutionEngine/JITMemoryManager.h"
+#include "llvm/ExecutionEngine/MCJIT.h"
+#include "llvm/ExecutionEngine/ObjectBuffer.h"
+#include "llvm/ExecutionEngine/ObjectImage.h"
+#include "llvm/ExecutionEngine/SectionMemoryManager.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/Support/DynamicLibrary.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/MutexGuard.h"
+
+using namespace llvm;
+
+namespace {
+
+static struct RegisterJIT {
+  RegisterJIT() { MCJIT::Register(); }
+} JITRegistrator;
+
+}
+
+extern "C" void LLVMLinkInMCJIT() {
+}
+
+ExecutionEngine *MCJIT::createJIT(Module *M,
+                                  std::string *ErrorStr,
+                                  JITMemoryManager *JMM,
+                                  bool GVsWithCode,
+                                  TargetMachine *TM) {
+  // Try to register the program as a source of symbols to resolve against.
+  //
+  // FIXME: Don't do this here.
+  sys::DynamicLibrary::LoadLibraryPermanently(0, NULL);
+
+  return new MCJIT(M, TM, JMM ? JMM : new SectionMemoryManager(), GVsWithCode);
+}
+
+MCJIT::MCJIT(Module *m, TargetMachine *tm, RTDyldMemoryManager *MM,
+             bool AllocateGVsWithCode)
+  : ExecutionEngine(m), TM(tm), Ctx(0),
+    MemMgr(MM ? MM : new SectionMemoryManager()), Dyld(MemMgr),
+    IsLoaded(false), M(m), ObjCache(0)  {
+
+  setDataLayout(TM->getDataLayout());
+}
+
+MCJIT::~MCJIT() {
+  if (LoadedObject)
+    NotifyFreeingObject(*LoadedObject.get());
+  delete MemMgr;
+  delete TM;
+}
+
+void MCJIT::setObjectCache(ObjectCache* NewCache) {
+  ObjCache = NewCache;
+}
+
+ObjectBufferStream* MCJIT::emitObject(Module *m) {
+  /// Currently, MCJIT only supports a single module and the module passed to
+  /// this function call is expected to be the contained module.  The module
+  /// is passed as a parameter here to prepare for multiple module support in
+  /// the future.
+  assert(M == m);
+
+  // Get a thread lock to make sure we aren't trying to compile multiple times
+  MutexGuard locked(lock);
+
+  // FIXME: Track compilation state on a per-module basis when multiple modules
+  //        are supported.
+  // Re-compilation is not supported
+  assert(!IsLoaded);
+
+  PassManager PM;
+
+  PM.add(new DataLayout(*TM->getDataLayout()));
+
+  // The RuntimeDyld will take ownership of this shortly
+  OwningPtr<ObjectBufferStream> CompiledObject(new ObjectBufferStream());
+
+  // Turn the machine code intermediate representation into bytes in memory
+  // that may be executed.
+  if (TM->addPassesToEmitMC(PM, Ctx, CompiledObject->getOStream(), false)) {
+    report_fatal_error("Target does not support MC emission!");
+  }
+
+  // Initialize passes.
+  PM.run(*m);
+  // Flush the output buffer to get the generated code into memory
+  CompiledObject->flush();
+
+  // If we have an object cache, tell it about the new object.
+  // Note that we're using the compiled image, not the loaded image (as below).
+  if (ObjCache) {
+    // MemoryBuffer is a thin wrapper around the actual memory, so it's OK
+    // to create a temporary object here and delete it after the call.
+    OwningPtr<MemoryBuffer> MB(CompiledObject->getMemBuffer());
+    ObjCache->notifyObjectCompiled(m, MB.get());
+  }
+
+  return CompiledObject.take();
+}
+
+void MCJIT::loadObject(Module *M) {
+
+  // Get a thread lock to make sure we aren't trying to load multiple times
+  MutexGuard locked(lock);
+
+  // FIXME: Track compilation state on a per-module basis when multiple modules
+  //        are supported.
+  // Re-compilation is not supported
+  if (IsLoaded)
+    return;
+
+  OwningPtr<ObjectBuffer> ObjectToLoad;
+  // Try to load the pre-compiled object from cache if possible
+  if (0 != ObjCache) {
+    OwningPtr<MemoryBuffer> PreCompiledObject(ObjCache->getObjectCopy(M));
+    if (0 != PreCompiledObject.get())
+      ObjectToLoad.reset(new ObjectBuffer(PreCompiledObject.take()));
+  }
+
+  // If the cache did not contain a suitable object, compile the object
+  if (!ObjectToLoad) {
+    ObjectToLoad.reset(emitObject(M));
+    assert(ObjectToLoad.get() && "Compilation did not produce an object.");
+  }
+
+  // Load the object into the dynamic linker.
+  // handing off ownership of the buffer
+  LoadedObject.reset(Dyld.loadObject(ObjectToLoad.take()));
+  if (!LoadedObject)
+    report_fatal_error(Dyld.getErrorString());
+
+  // Resolve any relocations.
+  Dyld.resolveRelocations();
+
+  // FIXME: Make this optional, maybe even move it to a JIT event listener
+  LoadedObject->registerWithDebugger();
+
+  NotifyObjectEmitted(*LoadedObject);
+
+  // FIXME: Add support for per-module compilation state
+  IsLoaded = true;
+}
+
+// FIXME: Add a parameter to identify which object is being finalized when
+// MCJIT supports multiple modules.
+// FIXME: Provide a way to separate code emission, relocations and page 
+// protection in the interface.
+void MCJIT::finalizeObject() {
+  // If the module hasn't been compiled, just do that.
+  if (!IsLoaded) {
+    // If the call to Dyld.resolveRelocations() is removed from loadObject()
+    // we'll need to do that here.
+    loadObject(M);
+  } else {
+    // Resolve any relocations.
+    Dyld.resolveRelocations();
+  }
+
+  StringRef EHData = Dyld.getEHFrameSection();
+  if (!EHData.empty())
+    MemMgr->registerEHFrames(EHData);
+
+  // Set page permissions.
+  MemMgr->applyPermissions();
+}
+
+void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
+  report_fatal_error("not yet implemented");
+}
+
+void *MCJIT::getPointerToFunction(Function *F) {
+  // FIXME: This should really return a uint64_t since it's a pointer in the
+  // target address space, not our local address space. That's part of the
+  // ExecutionEngine interface, though. Fix that when the old JIT finally
+  // dies.
+
+  // FIXME: Add support for per-module compilation state
+  if (!IsLoaded)
+    loadObject(M);
+
+  if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
+    bool AbortOnFailure = !F->hasExternalWeakLinkage();
+    void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
+    addGlobalMapping(F, Addr);
+    return Addr;
+  }
+
+  // FIXME: Should the Dyld be retaining module information? Probably not.
+  // FIXME: Should we be using the mangler for this? Probably.
+  //
+  // This is the accessor for the target address, so make sure to check the
+  // load address of the symbol, not the local address.
+  StringRef BaseName = F->getName();
+  if (BaseName[0] == '\1')
+    return (void*)Dyld.getSymbolLoadAddress(BaseName.substr(1));
+  return (void*)Dyld.getSymbolLoadAddress((TM->getMCAsmInfo()->getGlobalPrefix()
+                                       + BaseName).str());
+}
+
+void *MCJIT::recompileAndRelinkFunction(Function *F) {
+  report_fatal_error("not yet implemented");
+}
+
+void MCJIT::freeMachineCodeForFunction(Function *F) {
+  report_fatal_error("not yet implemented");
+}
+
+GenericValue MCJIT::runFunction(Function *F,
+                                const std::vector<GenericValue> &ArgValues) {
+  assert(F && "Function *F was null at entry to run()");
+
+  void *FPtr = getPointerToFunction(F);
+  assert(FPtr && "Pointer to fn's code was null after getPointerToFunction");
+  FunctionType *FTy = F->getFunctionType();
+  Type *RetTy = FTy->getReturnType();
+
+  assert((FTy->getNumParams() == ArgValues.size() ||
+          (FTy->isVarArg() && FTy->getNumParams() <= ArgValues.size())) &&
+         "Wrong number of arguments passed into function!");
+  assert(FTy->getNumParams() == ArgValues.size() &&
+         "This doesn't support passing arguments through varargs (yet)!");
+
+  // Handle some common cases first.  These cases correspond to common `main'
+  // prototypes.
+  if (RetTy->isIntegerTy(32) || RetTy->isVoidTy()) {
+    switch (ArgValues.size()) {
+    case 3:
+      if (FTy->getParamType(0)->isIntegerTy(32) &&
+          FTy->getParamType(1)->isPointerTy() &&
+          FTy->getParamType(2)->isPointerTy()) {
+        int (*PF)(int, char **, const char **) =
+          (int(*)(int, char **, const char **))(intptr_t)FPtr;
+
+        // Call the function.
+        GenericValue rv;
+        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
+                                 (char **)GVTOP(ArgValues[1]),
+                                 (const char **)GVTOP(ArgValues[2])));
+        return rv;
+      }
+      break;
+    case 2:
+      if (FTy->getParamType(0)->isIntegerTy(32) &&
+          FTy->getParamType(1)->isPointerTy()) {
+        int (*PF)(int, char **) = (int(*)(int, char **))(intptr_t)FPtr;
+
+        // Call the function.
+        GenericValue rv;
+        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue(),
+                                 (char **)GVTOP(ArgValues[1])));
+        return rv;
+      }
+      break;
+    case 1:
+      if (FTy->getNumParams() == 1 &&
+          FTy->getParamType(0)->isIntegerTy(32)) {
+        GenericValue rv;
+        int (*PF)(int) = (int(*)(int))(intptr_t)FPtr;
+        rv.IntVal = APInt(32, PF(ArgValues[0].IntVal.getZExtValue()));
+        return rv;
+      }
+      break;
+    }
+  }
+
+  // Handle cases where no arguments are passed first.
+  if (ArgValues.empty()) {
+    GenericValue rv;
+    switch (RetTy->getTypeID()) {
+    default: llvm_unreachable("Unknown return type for function call!");
+    case Type::IntegerTyID: {
+      unsigned BitWidth = cast<IntegerType>(RetTy)->getBitWidth();
+      if (BitWidth == 1)
+        rv.IntVal = APInt(BitWidth, ((bool(*)())(intptr_t)FPtr)());
+      else if (BitWidth <= 8)
+        rv.IntVal = APInt(BitWidth, ((char(*)())(intptr_t)FPtr)());
+      else if (BitWidth <= 16)
+        rv.IntVal = APInt(BitWidth, ((short(*)())(intptr_t)FPtr)());
+      else if (BitWidth <= 32)
+        rv.IntVal = APInt(BitWidth, ((int(*)())(intptr_t)FPtr)());
+      else if (BitWidth <= 64)
+        rv.IntVal = APInt(BitWidth, ((int64_t(*)())(intptr_t)FPtr)());
+      else
+        llvm_unreachable("Integer types > 64 bits not supported");
+      return rv;
+    }
+    case Type::VoidTyID:
+      rv.IntVal = APInt(32, ((int(*)())(intptr_t)FPtr)());
+      return rv;
+    case Type::FloatTyID:
+      rv.FloatVal = ((float(*)())(intptr_t)FPtr)();
+      return rv;
+    case Type::DoubleTyID:
+      rv.DoubleVal = ((double(*)())(intptr_t)FPtr)();
+      return rv;
+    case Type::X86_FP80TyID:
+    case Type::FP128TyID:
+    case Type::PPC_FP128TyID:
+      llvm_unreachable("long double not supported yet");
+    case Type::PointerTyID:
+      return PTOGV(((void*(*)())(intptr_t)FPtr)());
+    }
+  }
+
+  llvm_unreachable("Full-featured argument passing not supported yet!");
+}
+
+void *MCJIT::getPointerToNamedFunction(const std::string &Name,
+                                       bool AbortOnFailure) {
+  // FIXME: Add support for per-module compilation state
+  if (!IsLoaded)
+    loadObject(M);
+
+  if (!isSymbolSearchingDisabled() && MemMgr) {
+    void *ptr = MemMgr->getPointerToNamedFunction(Name, false);
+    if (ptr)
+      return ptr;
+  }
+
+  /// If a LazyFunctionCreator is installed, use it to get/create the function.
+  if (LazyFunctionCreator)
+    if (void *RP = LazyFunctionCreator(Name))
+      return RP;
+
+  if (AbortOnFailure) {
+    report_fatal_error("Program used external function '"+Name+
+                       "' which could not be resolved!");
+  }
+  return 0;
+}
+
+void MCJIT::RegisterJITEventListener(JITEventListener *L) {
+  if (L == NULL)
+    return;
+  MutexGuard locked(lock);
+  EventListeners.push_back(L);
+}
+void MCJIT::UnregisterJITEventListener(JITEventListener *L) {
+  if (L == NULL)
+    return;
+  MutexGuard locked(lock);
+  SmallVector<JITEventListener*, 2>::reverse_iterator I=
+      std::find(EventListeners.rbegin(), EventListeners.rend(), L);
+  if (I != EventListeners.rend()) {
+    std::swap(*I, EventListeners.back());
+    EventListeners.pop_back();
+  }
+}
+void MCJIT::NotifyObjectEmitted(const ObjectImage& Obj) {
+  MutexGuard locked(lock);
+  for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
+    EventListeners[I]->NotifyObjectEmitted(Obj);
+  }
+}
+void MCJIT::NotifyFreeingObject(const ObjectImage& Obj) {
+  MutexGuard locked(lock);
+  for (unsigned I = 0, S = EventListeners.size(); I < S; ++I) {
+    EventListeners[I]->NotifyFreeingObject(Obj);
+  }
+}
diff --git a/contrib/llvm/lib/ExecutionEngine/MCJIT/MCJIT.h b/contrib/llvm/lib/ExecutionEngine/MCJIT/MCJIT.h
new file mode 100644
index 0000000..8c4bf6e
--- /dev/null
+++ b/contrib/llvm/lib/ExecutionEngine/MCJIT/MCJIT.h
@@ -0,0 +1,123 @@
+//===-- MCJIT.h - Class definition for the MCJIT ----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_EXECUTIONENGINE_MCJIT_H
+#define LLVM_LIB_EXECUTIONENGINE_MCJIT_H
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ExecutionEngine/ExecutionEngine.h"
+#include "llvm/ExecutionEngine/ObjectCache.h"
+#include "llvm/ExecutionEngine/RuntimeDyld.h"
+#include "llvm/PassManager.h"
+
+namespace llvm {
+
+class ObjectImage;
+
+// FIXME: This makes all kinds of horrible assumptions for the time being,
+// like only having one module, not needing to worry about multi-threading,
+// blah blah. Purely in get-it-up-and-limping mode for now.
+
+class MCJIT : public ExecutionEngine {
+  MCJIT(Module *M, TargetMachine *tm, RTDyldMemoryManager *MemMgr,
+        bool AllocateGVsWithCode);
+
+  TargetMachine *TM;
+  MCContext *Ctx;
+  RTDyldMemoryManager *MemMgr;
+  RuntimeDyld Dyld;
+  SmallVector<JITEventListener*, 2> EventListeners;
+
+  // FIXME: Add support for multiple modules
+  bool IsLoaded;
+  Module *M;
+  OwningPtr<ObjectImage> LoadedObject;
+
+  // An optional ObjectCache to be notified of compiled objects and used to
+  // perform lookup of pre-compiled code to avoid re-compilation.
+  ObjectCache *ObjCache;
+
+public:
+  ~MCJIT();
+
+  /// @name ExecutionEngine interface implementation
+  /// @{
+
+  /// Sets the object manager that MCJIT should use to avoid compilation.
+  virtual void setObjectCache(ObjectCache *manager);
+
+  virtual void finalizeObject();
+
+  virtual void *getPointerToBasicBlock(BasicBlock *BB);
+
+  virtual void *getPointerToFunction(Function *F);
+
+  virtual void *recompileAndRelinkFunction(Function *F);
+
+  virtual void freeMachineCodeForFunction(Function *F);
+
+  virtual GenericValue runFunction(Function *F,
+                                   const std::vector<GenericValue> &ArgValues);
+
+  /// getPointerToNamedFunction - This method returns the address of the
+  /// specified function by using the dlsym function call.  As such it is only
+  /// useful for resolving library symbols, not code generated symbols.
+  ///
+  /// If AbortOnFailure is false and no function with the given name is
+  /// found, this function silently returns a null pointer. Otherwise,
+  /// it prints a message to stderr and aborts.
+  ///
+  virtual void *getPointerToNamedFunction(const std::string &Name,
+                                          bool AbortOnFailure = true);
+
+  /// mapSectionAddress - map a section to its target address space value.
+  /// Map the address of a JIT section as returned from the memory manager
+  /// to the address in the target process as the running code will see it.
+  /// This is the address which will be used for relocation resolution.
+  virtual void mapSectionAddress(const void *LocalAddress,
+                                 uint64_t TargetAddress) {
+    Dyld.mapSectionAddress(LocalAddress, TargetAddress);
+  }
+
+  virtual void RegisterJITEventListener(JITEventListener *L);
+  virtual void UnregisterJITEventListener(JITEventListener *L);
+
+  /// @}
+  /// @name (Private) Registration Interfaces
+  /// @{
+
+  static void Register() {
+    MCJITCtor = createJIT;
+  }
+
+  static ExecutionEngine *createJIT(Module *M,
+                                    std::string *ErrorStr,
+                                    JITMemoryManager *JMM,
+                                    bool GVsWithCode,
+                                    TargetMachine *TM);
+
+  // @}
+
+protected:
+  /// emitObject -- Generate a JITed object in memory from the specified module
+  /// Currently, MCJIT only supports a single module and the module passed to
+  /// this function call is expected to be the contained module.  The module
+  /// is passed as a parameter here to prepare for multiple module support in 
+  /// the future.
+  ObjectBufferStream* emitObject(Module *M);
+
+  void loadObject(Module *M);
+
+  void NotifyObjectEmitted(const ObjectImage& Obj);
+  void NotifyFreeingObject(const ObjectImage& Obj);
+};
+
+} // End llvm namespace
+
+#endif
diff --git a/contrib/llvm/lib/ExecutionEngine/MCJIT/SectionMemoryManager.cpp b/contrib/llvm/lib/ExecutionEngine/MCJIT/SectionMemoryManager.cpp
new file mode 100644
index 0000000..bac77ce
--- /dev/null
+++ b/contrib/llvm/lib/ExecutionEngine/MCJIT/SectionMemoryManager.cpp
@@ -0,0 +1,263 @@
+//===- SectionMemoryManager.cpp - Memory manager for MCJIT/RtDyld *- C++ -*-==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the section-based memory manager used by the MCJIT
+// execution engine and RuntimeDyld
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Config/config.h"
+#include "llvm/ExecutionEngine/SectionMemoryManager.h"
+#include "llvm/Support/DynamicLibrary.h"
+#include "llvm/Support/MathExtras.h"
+
+#ifdef __linux__
+  // These includes used by SectionMemoryManager::getPointerToNamedFunction()
+  // for Glibc trickery. See comments in this function for more information.
+  #ifdef HAVE_SYS_STAT_H
+    #include <sys/stat.h>
+  #endif
+  #include <fcntl.h>
+  #include <unistd.h>
+#endif
+
+namespace llvm {
+
+uint8_t *SectionMemoryManager::allocateDataSection(uintptr_t Size,
+                                                    unsigned Alignment,
+                                                    unsigned SectionID,
+                                                    bool IsReadOnly) {
+  if (IsReadOnly)
+    return allocateSection(RODataMem, Size, Alignment);
+  return allocateSection(RWDataMem, Size, Alignment);
+}
+
+uint8_t *SectionMemoryManager::allocateCodeSection(uintptr_t Size,
+                                                   unsigned Alignment,
+                                                   unsigned SectionID) {
+  return allocateSection(CodeMem, Size, Alignment);
+}
+
+uint8_t *SectionMemoryManager::allocateSection(MemoryGroup &MemGroup,
+                                               uintptr_t Size,
+                                               unsigned Alignment) {
+  if (!Alignment)
+    Alignment = 16;
+
+  assert(!(Alignment & (Alignment - 1)) && "Alignment must be a power of two.");
+
+  uintptr_t RequiredSize = Alignment * ((Size + Alignment - 1)/Alignment + 1);
+  uintptr_t Addr = 0;
+
+  // Look in the list of free memory regions and use a block there if one
+  // is available.
+  for (int i = 0, e = MemGroup.FreeMem.size(); i != e; ++i) {
+    sys::MemoryBlock &MB = MemGroup.FreeMem[i];
+    if (MB.size() >= RequiredSize) {
+      Addr = (uintptr_t)MB.base();
+      uintptr_t EndOfBlock = Addr + MB.size();
+      // Align the address.
+      Addr = (Addr + Alignment - 1) & ~(uintptr_t)(Alignment - 1);
+      // Store cutted free memory block.
+      MemGroup.FreeMem[i] = sys::MemoryBlock((void*)(Addr + Size),
+                                             EndOfBlock - Addr - Size);
+      return (uint8_t*)Addr;
+    }
+  }
+
+  // No pre-allocated free block was large enough. Allocate a new memory region.
+  // Note that all sections get allocated as read-write.  The permissions will
+  // be updated later based on memory group.
+  //
+  // FIXME: It would be useful to define a default allocation size (or add
+  // it as a constructor parameter) to minimize the number of allocations.
+  //
+  // FIXME: Initialize the Near member for each memory group to avoid
+  // interleaving.
+  error_code ec;
+  sys::MemoryBlock MB = sys::Memory::allocateMappedMemory(RequiredSize,
+                                                          &MemGroup.Near,
+                                                          sys::Memory::MF_READ |
+                                                            sys::Memory::MF_WRITE,
+                                                          ec);
+  if (ec) {
+    // FIXME: Add error propogation to the interface.
+    return NULL;
+  }
+
+  // Save this address as the basis for our next request
+  MemGroup.Near = MB;
+
+  MemGroup.AllocatedMem.push_back(MB);
+  Addr = (uintptr_t)MB.base();
+  uintptr_t EndOfBlock = Addr + MB.size();
+
+  // Align the address.
+  Addr = (Addr + Alignment - 1) & ~(uintptr_t)(Alignment - 1);
+
+  // The allocateMappedMemory may allocate much more memory than we need. In
+  // this case, we store the unused memory as a free memory block.
+  unsigned FreeSize = EndOfBlock-Addr-Size;
+  if (FreeSize > 16)
+    MemGroup.FreeMem.push_back(sys::MemoryBlock((void*)(Addr + Size), FreeSize));
+
+  // Return aligned address
+  return (uint8_t*)Addr;
+}
+
+bool SectionMemoryManager::applyPermissions(std::string *ErrMsg)
+{
+  // FIXME: Should in-progress permissions be reverted if an error occurs?
+  error_code ec;
+
+  // Make code memory executable.
+  ec = applyMemoryGroupPermissions(CodeMem,
+                                   sys::Memory::MF_READ | sys::Memory::MF_EXEC);
+  if (ec) {
+    if (ErrMsg) {
+      *ErrMsg = ec.message();
+    }
+    return true;
+  }
+
+  // Make read-only data memory read-only.
+  ec = applyMemoryGroupPermissions(RODataMem,
+                                   sys::Memory::MF_READ | sys::Memory::MF_EXEC);
+  if (ec) {
+    if (ErrMsg) {
+      *ErrMsg = ec.message();
+    }
+    return true;
+  }
+
+  // Read-write data memory already has the correct permissions
+
+  // Some platforms with separate data cache and instruction cache require
+  // explicit cache flush, otherwise JIT code manipulations (like resolved
+  // relocations) will get to the data cache but not to the instruction cache.
+  invalidateInstructionCache();
+
+  return false;
+}
+
+// Determine whether we can register EH tables.
+#if (defined(__GNUC__) && !defined(__ARM_EABI__) && \
+     !defined(__USING_SJLJ_EXCEPTIONS__))
+#define HAVE_EHTABLE_SUPPORT 1
+#else
+#define HAVE_EHTABLE_SUPPORT 0
+#endif
+
+#if HAVE_EHTABLE_SUPPORT
+extern "C" void __register_frame(void*);
+
+static const char *processFDE(const char *Entry) {
+  const char *P = Entry;
+  uint32_t Length = *((uint32_t*)P);
+  P += 4;
+  uint32_t Offset = *((uint32_t*)P);
+  if (Offset != 0)
+    __register_frame((void*)Entry);
+  return P + Length;
+}
+#endif
+
+void SectionMemoryManager::registerEHFrames(StringRef SectionData) {
+#if HAVE_EHTABLE_SUPPORT
+  const char *P = SectionData.data();
+  const char *End = SectionData.data() + SectionData.size();
+  do  {
+    P = processFDE(P);
+  } while(P != End);
+#endif
+}
+
+error_code SectionMemoryManager::applyMemoryGroupPermissions(MemoryGroup &MemGroup,
+                                                             unsigned Permissions) {
+
+  for (int i = 0, e = MemGroup.AllocatedMem.size(); i != e; ++i) {
+      error_code ec;
+      ec = sys::Memory::protectMappedMemory(MemGroup.AllocatedMem[i],
+                                            Permissions);
+      if (ec) {
+        return ec;
+      }
+  }
+
+  return error_code::success();
+}
+
+void SectionMemoryManager::invalidateInstructionCache() {
+  for (int i = 0, e = CodeMem.AllocatedMem.size(); i != e; ++i)
+    sys::Memory::InvalidateInstructionCache(CodeMem.AllocatedMem[i].base(),
+                                            CodeMem.AllocatedMem[i].size());
+}
+
+static int jit_noop() {
+  return 0;
+}
+
+void *SectionMemoryManager::getPointerToNamedFunction(const std::string &Name,
+                                                       bool AbortOnFailure) {
+#if defined(__linux__)
+  //===--------------------------------------------------------------------===//
+  // Function stubs that are invoked instead of certain library calls
+  //
+  // Force the following functions to be linked in to anything that uses the
+  // JIT. This is a hack designed to work around the all-too-clever Glibc
+  // strategy of making these functions work differently when inlined vs. when
+  // not inlined, and hiding their real definitions in a separate archive file
+  // that the dynamic linker can't see. For more info, search for
+  // 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
+  if (Name == "stat") return (void*)(intptr_t)&stat;
+  if (Name == "fstat") return (void*)(intptr_t)&fstat;
+  if (Name == "lstat") return (void*)(intptr_t)&lstat;
+  if (Name == "stat64") return (void*)(intptr_t)&stat64;
+  if (Name == "fstat64") return (void*)(intptr_t)&fstat64;
+  if (Name == "lstat64") return (void*)(intptr_t)&lstat64;
+  if (Name == "atexit") return (void*)(intptr_t)&atexit;
+  if (Name == "mknod") return (void*)(intptr_t)&mknod;
+#endif // __linux__
+
+  // We should not invoke parent's ctors/dtors from generated main()!
+  // On Mingw and Cygwin, the symbol __main is resolved to
+  // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
+  // (and register wrong callee's dtors with atexit(3)).
+  // We expect ExecutionEngine::runStaticConstructorsDestructors()
+  // is called before ExecutionEngine::runFunctionAsMain() is called.
+  if (Name == "__main") return (void*)(intptr_t)&jit_noop;
+
+  const char *NameStr = Name.c_str();
+  void *Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr);
+  if (Ptr) return Ptr;
+
+  // If it wasn't found and if it starts with an underscore ('_') character,
+  // try again without the underscore.
+  if (NameStr[0] == '_') {
+    Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr+1);
+    if (Ptr) return Ptr;
+  }
+
+  if (AbortOnFailure)
+    report_fatal_error("Program used external function '" + Name +
+                      "' which could not be resolved!");
+  return 0;
+}
+
+SectionMemoryManager::~SectionMemoryManager() {
+  for (unsigned i = 0, e = CodeMem.AllocatedMem.size(); i != e; ++i)
+    sys::Memory::releaseMappedMemory(CodeMem.AllocatedMem[i]);
+  for (unsigned i = 0, e = RWDataMem.AllocatedMem.size(); i != e; ++i)
+    sys::Memory::releaseMappedMemory(RWDataMem.AllocatedMem[i]);
+  for (unsigned i = 0, e = RODataMem.AllocatedMem.size(); i != e; ++i)
+    sys::Memory::releaseMappedMemory(RODataMem.AllocatedMem[i]);
+}
+
+} // namespace llvm
+