Vendor import of llvm trunk r161861:

http://llvm.org/svn/llvm-project/llvm/trunk@161861

19 files changed, 359 insertions, 238 deletions

diff --git a/lib/ExecutionEngine/EventListenerCommon.h b/lib/ExecutionEngine/EventListenerCommon.h
index 1c07c94..911d1d6 100644
--- a/lib/ExecutionEngine/EventListenerCommon.h
+++ b/lib/ExecutionEngine/EventListenerCommon.h
@@ -14,8 +14,8 @@
 #ifndef EVENT_LISTENER_COMMON_H
 #define EVENT_LISTENER_COMMON_H
 
+#include "llvm/DebugInfo.h"
 #include "llvm/Metadata.h"
-#include "llvm/Analysis/DebugInfo.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/Support/ValueHandle.h"
 #include "llvm/Support/Path.h"
diff --git a/lib/ExecutionEngine/IntelJITEvents/IntelJITEventListener.cpp b/lib/ExecutionEngine/IntelJITEvents/IntelJITEventListener.cpp
index 5dfa78f..c11c17e 100644
--- a/lib/ExecutionEngine/IntelJITEvents/IntelJITEventListener.cpp
+++ b/lib/ExecutionEngine/IntelJITEvents/IntelJITEventListener.cpp
@@ -16,11 +16,11 @@
 #include "llvm/ExecutionEngine/JITEventListener.h"
 
 #define DEBUG_TYPE "amplifier-jit-event-listener"
+#include "llvm/DebugInfo.h"
 #include "llvm/Function.h"
 #include "llvm/Metadata.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/OwningPtr.h"
-#include "llvm/Analysis/DebugInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/ExecutionEngine/IntelJITEventsWrapper.h"
 #include "llvm/Support/Debug.h"
@@ -138,7 +138,7 @@ void IntelJITEventListener::NotifyFunctionEmitted(
       // the first instruction that has one
       if (FunctionMessage.source_file_name == 0) {
         MDNode *scope = I->Loc.getScope(
-					Details.MF->getFunction()->getContext());
+          Details.MF->getFunction()->getContext());
         FunctionMessage.source_file_name = const_cast<char*>(
                                                   Filenames.getFullPath(scope));
       }
@@ -152,7 +152,7 @@ void IntelJITEventListener::NotifyFunctionEmitted(
   }
 
   Wrapper.iJIT_NotifyEvent(iJVM_EVENT_TYPE_METHOD_LOAD_FINISHED,
-													 &FunctionMessage);
+                           &FunctionMessage);
   MethodIDs[FnStart] = FunctionMessage.method_id;
 }
 
diff --git a/lib/ExecutionEngine/Interpreter/CMakeLists.txt b/lib/ExecutionEngine/Interpreter/CMakeLists.txt
index d331f83..74df8f0 100644
--- a/lib/ExecutionEngine/Interpreter/CMakeLists.txt
+++ b/lib/ExecutionEngine/Interpreter/CMakeLists.txt
@@ -15,3 +15,5 @@ add_llvm_library(LLVMInterpreter
 if( LLVM_ENABLE_FFI )
   target_link_libraries( LLVMInterpreter ${FFI_LIBRARY_PATH} )
 endif()
+
+add_dependencies(LLVMInterpreter intrinsics_gen)
diff --git a/lib/ExecutionEngine/Interpreter/Execution.cpp b/lib/ExecutionEngine/Interpreter/Execution.cpp
index af47be9..5202b09 100644
--- a/lib/ExecutionEngine/Interpreter/Execution.cpp
+++ b/lib/ExecutionEngine/Interpreter/Execution.cpp
@@ -651,11 +651,40 @@ void Interpreter::visitSwitchInst(SwitchInst &I) {
   // Check to see if any of the cases match...
   BasicBlock *Dest = 0;
   for (SwitchInst::CaseIt i = I.case_begin(), e = I.case_end(); i != e; ++i) {
-    GenericValue CaseVal = getOperandValue(i.getCaseValue(), SF);
-    if (executeICMP_EQ(CondVal, CaseVal, ElTy).IntVal != 0) {
-      Dest = cast<BasicBlock>(i.getCaseSuccessor());
-      break;
+    IntegersSubset& Case = i.getCaseValueEx();
+    if (Case.isSingleNumber()) {
+      // FIXME: Currently work with ConstantInt based numbers.
+      const ConstantInt *CI = Case.getSingleNumber(0).toConstantInt();
+      GenericValue Val = getOperandValue(const_cast<ConstantInt*>(CI), SF);
+      if (executeICMP_EQ(Val, CondVal, ElTy).IntVal != 0) {
+        Dest = cast<BasicBlock>(i.getCaseSuccessor());
+        break;        
+      }
     }
+    if (Case.isSingleNumbersOnly()) {
+      for (unsigned n = 0, en = Case.getNumItems(); n != en; ++n) {
+        // FIXME: Currently work with ConstantInt based numbers.
+        const ConstantInt *CI = Case.getSingleNumber(n).toConstantInt();
+        GenericValue Val = getOperandValue(const_cast<ConstantInt*>(CI), SF);
+        if (executeICMP_EQ(Val, CondVal, ElTy).IntVal != 0) {
+          Dest = cast<BasicBlock>(i.getCaseSuccessor());
+          break;        
+        }
+      }      
+    } else
+      for (unsigned n = 0, en = Case.getNumItems(); n != en; ++n) {
+        IntegersSubset::Range r = Case.getItem(n);
+        // FIXME: Currently work with ConstantInt based numbers.
+        const ConstantInt *LowCI = r.getLow().toConstantInt();
+        const ConstantInt *HighCI = r.getHigh().toConstantInt();
+        GenericValue Low = getOperandValue(const_cast<ConstantInt*>(LowCI), SF);
+        GenericValue High = getOperandValue(const_cast<ConstantInt*>(HighCI), SF);
+        if (executeICMP_ULE(Low, CondVal, ElTy).IntVal != 0 &&
+            executeICMP_ULE(CondVal, High, ElTy).IntVal != 0) {
+          Dest = cast<BasicBlock>(i.getCaseSuccessor());
+          break;        
+        }
+      }
   }
   if (!Dest) Dest = I.getDefaultDest();   // No cases matched: use default
   SwitchToNewBasicBlock(Dest, SF);
diff --git a/lib/ExecutionEngine/JIT/JIT.cpp b/lib/ExecutionEngine/JIT/JIT.cpp
index a942299..97995ad 100644
--- a/lib/ExecutionEngine/JIT/JIT.cpp
+++ b/lib/ExecutionEngine/JIT/JIT.cpp
@@ -361,7 +361,7 @@ bool JIT::removeModule(Module *M) {
 
   MutexGuard locked(lock);
 
-  if (jitstate->getModule() == M) {
+  if (jitstate && jitstate->getModule() == M) {
     delete jitstate;
     jitstate = 0;
   }
@@ -433,13 +433,18 @@ GenericValue JIT::runFunction(Function *F,
       }
       break;
     case 1:
-      if (FTy->getNumParams() == 1 &&
-          FTy->getParamType(0)->isIntegerTy(32)) {
+      if (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;
       }
+      if (FTy->getParamType(0)->isPointerTy()) {
+        GenericValue rv;
+        int (*PF)(char *) = (int(*)(char *))(intptr_t)FPtr;
+        rv.IntVal = APInt(32, PF((char*)GVTOP(ArgValues[0])));
+        return rv;
+      }
       break;
     }
   }
diff --git a/lib/ExecutionEngine/JIT/JITEmitter.cpp b/lib/ExecutionEngine/JIT/JITEmitter.cpp
index 504c8bd..ff3a9dc 100644
--- a/lib/ExecutionEngine/JIT/JITEmitter.cpp
+++ b/lib/ExecutionEngine/JIT/JITEmitter.cpp
@@ -17,9 +17,9 @@
 #include "JITDwarfEmitter.h"
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Constants.h"
-#include "llvm/Module.h"
+#include "llvm/DebugInfo.h"
 #include "llvm/DerivedTypes.h"
-#include "llvm/Analysis/DebugInfo.h"
+#include "llvm/Module.h"
 #include "llvm/CodeGen/JITCodeEmitter.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineCodeInfo.h"
@@ -108,13 +108,18 @@ namespace {
     /// particular GlobalVariable so that we can reuse them if necessary.
     GlobalToIndirectSymMapTy GlobalToIndirectSymMap;
 
+#ifndef NDEBUG
     /// Instance of the JIT this ResolverState serves.
     JIT *TheJIT;
+#endif
 
   public:
     JITResolverState(JIT *jit) : FunctionToLazyStubMap(this),
-                                 FunctionToCallSitesMap(this),
-                                 TheJIT(jit) {}
+                                 FunctionToCallSitesMap(this) {
+#ifndef NDEBUG
+      TheJIT = jit;
+#endif
+    }
 
     FunctionToLazyStubMapTy& getFunctionToLazyStubMap(
       const MutexGuard& locked) {
diff --git a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
index 2d1775c..7be6ef8 100644
--- a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
+++ b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
@@ -852,7 +852,7 @@ static int jit_noop() {
 /// for resolving library symbols, not code generated symbols.
 ///
 void *DefaultJITMemoryManager::getPointerToNamedFunction(const std::string &Name,
-                                     bool AbortOnFailure) {
+                                                         bool AbortOnFailure) {
   // Check to see if this is one of the functions we want to intercept.  Note,
   // we cast to intptr_t here to silence a -pedantic warning that complains
   // about casting a function pointer to a normal pointer.
diff --git a/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 44f89cf..739ffd7d8 100644
--- a/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/DynamicLibrary.h"
 #include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/MutexGuard.h"
 #include "llvm/Target/TargetData.h"
 
 using namespace llvm;
@@ -45,7 +46,7 @@ ExecutionEngine *MCJIT::createJIT(Module *M,
 
   // If the target supports JIT code generation, create the JIT.
   if (TargetJITInfo *TJ = TM->getJITInfo())
-    return new MCJIT(M, TM, *TJ, new MCJITMemoryManager(JMM, M), GVsWithCode);
+    return new MCJIT(M, TM, *TJ, new MCJITMemoryManager(JMM), GVsWithCode);
 
   if (ErrorStr)
     *ErrorStr = "target does not support JIT code generation";
@@ -54,9 +55,35 @@ ExecutionEngine *MCJIT::createJIT(Module *M,
 
 MCJIT::MCJIT(Module *m, TargetMachine *tm, TargetJITInfo &tji,
              RTDyldMemoryManager *MM, bool AllocateGVsWithCode)
-  : ExecutionEngine(m), TM(tm), MemMgr(MM), M(m), OS(Buffer), Dyld(MM) {
+  : ExecutionEngine(m), TM(tm), Ctx(0), MemMgr(MM), Dyld(MM), 
+    isCompiled(false), M(m), OS(Buffer)  {
 
   setTargetData(TM->getTargetData());
+}
+
+MCJIT::~MCJIT() {
+  delete MemMgr;
+  delete TM;
+}
+
+void 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
+  if (isCompiled)
+    return;
+
+  PassManager PM;
+
   PM.add(new TargetData(*TM->getTargetData()));
 
   // Turn the machine code intermediate representation into bytes in memory
@@ -69,23 +96,22 @@ MCJIT::MCJIT(Module *m, TargetMachine *tm, TargetJITInfo &tji,
   // FIXME: When we support multiple modules, we'll want to move the code
   // gen and finalization out of the constructor here and do it more
   // on-demand as part of getPointerToFunction().
-  PM.run(*M);
+  PM.run(*m);
   // Flush the output buffer so the SmallVector gets its data.
   OS.flush();
 
   // Load the object into the dynamic linker.
-  MemoryBuffer *MB = MemoryBuffer::getMemBuffer(StringRef(Buffer.data(),
+  MemoryBuffer* MB = MemoryBuffer::getMemBuffer(StringRef(Buffer.data(),
                                                           Buffer.size()),
                                                 "", false);
   if (Dyld.loadObject(MB))
     report_fatal_error(Dyld.getErrorString());
+
   // Resolve any relocations.
   Dyld.resolveRelocations();
-}
 
-MCJIT::~MCJIT() {
-  delete MemMgr;
-  delete TM;
+  // FIXME: Add support for per-module compilation state
+  isCompiled = true;
 }
 
 void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
@@ -93,6 +119,10 @@ void *MCJIT::getPointerToBasicBlock(BasicBlock *BB) {
 }
 
 void *MCJIT::getPointerToFunction(Function *F) {
+  // FIXME: Add support for per-module compilation state
+  if (!isCompiled)
+    emitObject(M);
+
   if (F->isDeclaration() || F->hasAvailableExternallyLinkage()) {
     bool AbortOnFailure = !F->hasExternalWeakLinkage();
     void *Addr = getPointerToNamedFunction(F->getName(), AbortOnFailure);
@@ -100,6 +130,7 @@ void *MCJIT::getPointerToFunction(Function *F) {
     return Addr;
   }
 
+  // FIXME: Should the Dyld be retaining module information? Probably not.
   // FIXME: Should we be using the mangler for this? Probably.
   StringRef BaseName = F->getName();
   if (BaseName[0] == '\1')
@@ -217,7 +248,11 @@ GenericValue MCJIT::runFunction(Function *F,
 }
 
 void *MCJIT::getPointerToNamedFunction(const std::string &Name,
-                                       bool AbortOnFailure){
+                                       bool AbortOnFailure) {
+  // FIXME: Add support for per-module compilation state
+  if (!isCompiled)
+    emitObject(M);
+
   if (!isSymbolSearchingDisabled() && MemMgr) {
     void *ptr = MemMgr->getPointerToNamedFunction(Name, false);
     if (ptr)
@@ -231,7 +266,7 @@ void *MCJIT::getPointerToNamedFunction(const std::string &Name,
 
   if (AbortOnFailure) {
     report_fatal_error("Program used external function '"+Name+
-                      "' which could not be resolved!");
+                       "' which could not be resolved!");
   }
   return 0;
 }
diff --git a/lib/ExecutionEngine/MCJIT/MCJIT.h b/lib/ExecutionEngine/MCJIT/MCJIT.h
index 2b3df98..1d272e9 100644
--- a/lib/ExecutionEngine/MCJIT/MCJIT.h
+++ b/lib/ExecutionEngine/MCJIT/MCJIT.h
@@ -29,17 +29,16 @@ class MCJIT : public ExecutionEngine {
   TargetMachine *TM;
   MCContext *Ctx;
   RTDyldMemoryManager *MemMgr;
+  RuntimeDyld Dyld;
 
-  // FIXME: These may need moved to a separate 'jitstate' member like the
-  // non-MC JIT does for multithreading and such. Just keep them here for now.
-  PassManager PM;
+  // FIXME: Add support for multiple modules
+  bool isCompiled;
   Module *M;
-  // FIXME: This really doesn't belong here.
+
+  // FIXME: Move these to a single container which manages JITed objects
   SmallVector<char, 4096> Buffer; // Working buffer into which we JIT.
   raw_svector_ostream OS;
 
-  RuntimeDyld Dyld;
-
 public:
   ~MCJIT();
 
@@ -91,6 +90,14 @@ public:
                                     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.
+  void emitObject(Module *M);
 };
 
 } // End llvm namespace
diff --git a/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h b/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h
index a68949a..441aaeb 100644
--- a/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h
+++ b/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h
@@ -22,24 +22,20 @@ namespace llvm {
 // matching LLVM IR counterparts in the module(s) being compiled.
 class MCJITMemoryManager : public RTDyldMemoryManager {
   virtual void anchor();
-  JITMemoryManager *JMM;
+  OwningPtr<JITMemoryManager> JMM;
 
-  // FIXME: Multiple modules.
-  Module *M;
 public:
-  MCJITMemoryManager(JITMemoryManager *jmm, Module *m) :
-    JMM(jmm?jmm:JITMemoryManager::CreateDefaultMemManager()), M(m) {}
-  // We own the JMM, so make sure to delete it.
-  ~MCJITMemoryManager() { delete JMM; }
+  MCJITMemoryManager(JITMemoryManager *jmm) :
+    JMM(jmm?jmm:JITMemoryManager::CreateDefaultMemManager()) {}
 
   uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
                                unsigned SectionID) {
-    return JMM->allocateSpace(Size, Alignment);
+    return JMM->allocateDataSection(Size, Alignment, SectionID);
   }
 
   uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
                                unsigned SectionID) {
-    return JMM->allocateSpace(Size, Alignment);
+    return JMM->allocateCodeSection(Size, Alignment, SectionID);
   }
 
   virtual void *getPointerToNamedFunction(const std::string &Name,
diff --git a/lib/ExecutionEngine/OProfileJIT/OProfileJITEventListener.cpp b/lib/ExecutionEngine/OProfileJIT/OProfileJITEventListener.cpp
index e6142e3..6b8e9d1 100644
--- a/lib/ExecutionEngine/OProfileJIT/OProfileJITEventListener.cpp
+++ b/lib/ExecutionEngine/OProfileJIT/OProfileJITEventListener.cpp
@@ -16,9 +16,9 @@
 #include "llvm/ExecutionEngine/JITEventListener.h"
 
 #define DEBUG_TYPE "oprofile-jit-event-listener"
+#include "llvm/DebugInfo.h"
 #include "llvm/Function.h"
 #include "llvm/ADT/OwningPtr.h"
-#include "llvm/Analysis/DebugInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/ExecutionEngine/OProfileWrapper.h"
 #include "llvm/Support/Debug.h"
diff --git a/lib/ExecutionEngine/RuntimeDyld/ObjectImage.h b/lib/ExecutionEngine/RuntimeDyld/ObjectImage.h
index 8206ead..c3e3572 100644
--- a/lib/ExecutionEngine/RuntimeDyld/ObjectImage.h
+++ b/lib/ExecutionEngine/RuntimeDyld/ObjectImage.h
@@ -48,7 +48,7 @@ public:
   virtual void updateSymbolAddress(const object::SymbolRef &Sym, uint64_t Addr)
               {}
 
-  // Subclasses can override this method to provide JIT debugging support
+  // Subclasses can override these methods to provide JIT debugging support
   virtual void registerWithDebugger() {}
   virtual void deregisterWithDebugger() {}
 };
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index 1b1840a..b464040 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -39,7 +39,7 @@ namespace {
 // Resolve the relocations for all symbols we currently know about.
 void RuntimeDyldImpl::resolveRelocations() {
   // First, resolve relocations associated with external symbols.
-  resolveSymbols();
+  resolveExternalSymbols();
 
   // Just iterate over the sections we have and resolve all the relocations
   // in them. Gross overkill, but it gets the job done.
@@ -59,8 +59,8 @@ void RuntimeDyldImpl::mapSectionAddress(void *LocalAddress,
   llvm_unreachable("Attempting to remap address of unknown section!");
 }
 
-// Subclasses can implement this method to create specialized image instances
-// The caller owns the the pointer that is returned.
+// Subclasses can implement this method to create specialized image instances.
+// The caller owns the pointer that is returned.
 ObjectImage *RuntimeDyldImpl::createObjectImage(const MemoryBuffer *InputBuffer) {
   ObjectFile *ObjFile = ObjectFile::createObjectFile(const_cast<MemoryBuffer*>
                                                                  (InputBuffer));
@@ -75,11 +75,15 @@ bool RuntimeDyldImpl::loadObject(const MemoryBuffer *InputBuffer) {
 
   Arch = (Triple::ArchType)obj->getArch();
 
-  LocalSymbolMap LocalSymbols;     // Functions and data symbols from the
-                                   // object file.
-  ObjSectionToIDMap LocalSections; // Used sections from the object file
-  CommonSymbolMap   CommonSymbols; // Common symbols requiring allocation
-  uint64_t          CommonSize = 0;
+  // Symbols found in this object
+  StringMap<SymbolLoc> LocalSymbols;
+  // Used sections from the object file
+  ObjSectionToIDMap LocalSections;
+
+  // Common symbols requiring allocation, and the total size required to
+  // allocate all common symbols.
+  CommonSymbolMap CommonSymbols;
+  uint64_t CommonSize = 0;
 
   error_code err;
   // Parse symbols
@@ -106,28 +110,29 @@ bool RuntimeDyldImpl::loadObject(const MemoryBuffer *InputBuffer) {
       if (SymType == object::SymbolRef::ST_Function ||
           SymType == object::SymbolRef::ST_Data) {
         uint64_t FileOffset;
-        StringRef sData;
+        StringRef SectionData;
         section_iterator si = obj->end_sections();
         Check(i->getFileOffset(FileOffset));
         Check(i->getSection(si));
         if (si == obj->end_sections()) continue;
-        Check(si->getContents(sData));
+        Check(si->getContents(SectionData));
         const uint8_t* SymPtr = (const uint8_t*)InputBuffer->getBufferStart() +
                                 (uintptr_t)FileOffset;
-        uintptr_t SectOffset = (uintptr_t)(SymPtr - (const uint8_t*)sData.begin());
+        uintptr_t SectOffset = (uintptr_t)(SymPtr -
+                                           (const uint8_t*)SectionData.begin());
         unsigned SectionID =
           findOrEmitSection(*obj,
                             *si,
                             SymType == object::SymbolRef::ST_Function,
                             LocalSections);
-        bool isGlobal = flags & SymbolRef::SF_Global;
         LocalSymbols[Name.data()] = SymbolLoc(SectionID, SectOffset);
         DEBUG(dbgs() << "\tFileOffset: " << format("%p", (uintptr_t)FileOffset)
                      << " flags: " << flags
                      << " SID: " << SectionID
                      << " Offset: " << format("%p", SectOffset));
+        bool isGlobal = flags & SymbolRef::SF_Global;
         if (isGlobal)
-          SymbolTable[Name] = SymbolLoc(SectionID, SectOffset);
+          GlobalSymbolTable[Name] = SymbolLoc(SectionID, SectOffset);
       }
     }
     DEBUG(dbgs() << "\tType: " << SymType << " Name: " << Name << "\n");
@@ -137,7 +142,7 @@ bool RuntimeDyldImpl::loadObject(const MemoryBuffer *InputBuffer) {
   if (CommonSize != 0)
     emitCommonSymbols(*obj, CommonSymbols, CommonSize, LocalSymbols);
 
-  // Parse and proccess relocations
+  // Parse and process relocations
   DEBUG(dbgs() << "Parse relocations:\n");
   for (section_iterator si = obj->begin_sections(),
        se = obj->end_sections(); si != se; si.increment(err)) {
@@ -150,7 +155,7 @@ bool RuntimeDyldImpl::loadObject(const MemoryBuffer *InputBuffer) {
          e = si->end_relocations(); i != e; i.increment(err)) {
       Check(err);
 
-      // If it's first relocation in this section, find its SectionID
+      // If it's the first relocation in this section, find its SectionID
       if (isFirstRelocation) {
         SectionID = findOrEmitSection(*obj, *si, true, LocalSections);
         DEBUG(dbgs() << "\tSectionID: " << SectionID << "\n");
@@ -177,10 +182,10 @@ bool RuntimeDyldImpl::loadObject(const MemoryBuffer *InputBuffer) {
   return false;
 }
 
-unsigned RuntimeDyldImpl::emitCommonSymbols(ObjectImage &Obj,
-                                            const CommonSymbolMap &Map,
-                                            uint64_t TotalSize,
-                                            LocalSymbolMap &LocalSymbols) {
+void RuntimeDyldImpl::emitCommonSymbols(ObjectImage &Obj,
+                                        const CommonSymbolMap &CommonSymbols,
+                                        uint64_t TotalSize,
+                                        SymbolTableMap &SymbolTable) {
   // Allocate memory for the section
   unsigned SectionID = Sections.size();
   uint8_t *Addr = MemMgr->allocateDataSection(TotalSize, sizeof(void*),
@@ -197,18 +202,16 @@ unsigned RuntimeDyldImpl::emitCommonSymbols(ObjectImage &Obj,
                << "\n");
 
   // Assign the address of each symbol
-  for (CommonSymbolMap::const_iterator it = Map.begin(), itEnd = Map.end();
-       it != itEnd; it++) {
-    uint64_t Size = it->second;
+  for (CommonSymbolMap::const_iterator it = CommonSymbols.begin(),
+       itEnd = CommonSymbols.end(); it != itEnd; it++) {
     StringRef Name;
     it->first.getName(Name);
     Obj.updateSymbolAddress(it->first, (uint64_t)Addr);
-    LocalSymbols[Name.data()] = SymbolLoc(SectionID, Offset);
+    SymbolTable[Name.data()] = SymbolLoc(SectionID, Offset);
+    uint64_t Size = it->second;
     Offset += Size;
     Addr += Size;
   }
-
-  return SectionID;
 }
 
 unsigned RuntimeDyldImpl::emitSection(ObjectImage &Obj,
@@ -274,8 +277,8 @@ unsigned RuntimeDyldImpl::emitSection(ObjectImage &Obj,
   }
   else {
     // Even if we didn't load the section, we need to record an entry for it
-    //   to handle later processing (and by 'handle' I mean don't do anything
-    //   with these sections).
+    // to handle later processing (and by 'handle' I mean don't do anything
+    // with these sections).
     Allocate = 0;
     Addr = 0;
     DEBUG(dbgs() << "emitSection SectionID: " << SectionID
@@ -307,28 +310,26 @@ unsigned RuntimeDyldImpl::findOrEmitSection(ObjectImage &Obj,
   return SectionID;
 }
 
-void RuntimeDyldImpl::AddRelocation(const RelocationValueRef &Value,
-                                   unsigned SectionID, uintptr_t Offset,
-                                   uint32_t RelType) {
-  DEBUG(dbgs() << "AddRelocation SymNamePtr: " << format("%p", Value.SymbolName)
-               << " SID: " << Value.SectionID
-               << " Addend: " << format("%p", Value.Addend)
-               << " Offset: " << format("%p", Offset)
-               << " RelType: " << format("%x", RelType)
-               << "\n");
+void RuntimeDyldImpl::addRelocationForSection(const RelocationEntry &RE,
+                                              unsigned SectionID) {
+  Relocations[SectionID].push_back(RE);
+}
 
-  if (Value.SymbolName == 0) {
-    Relocations[Value.SectionID].push_back(RelocationEntry(
-      SectionID,
-      Offset,
-      RelType,
-      Value.Addend));
-  } else
-    SymbolRelocations[Value.SymbolName].push_back(RelocationEntry(
-      SectionID,
-      Offset,
-      RelType,
-      Value.Addend));
+void RuntimeDyldImpl::addRelocationForSymbol(const RelocationEntry &RE,
+                                             StringRef SymbolName) {
+  // Relocation by symbol.  If the symbol is found in the global symbol table,
+  // create an appropriate section relocation.  Otherwise, add it to
+  // ExternalSymbolRelocations.
+  SymbolTableMap::const_iterator Loc =
+      GlobalSymbolTable.find(SymbolName);
+  if (Loc == GlobalSymbolTable.end()) {
+    ExternalSymbolRelocations[SymbolName].push_back(RE);
+  } else {
+    // Copy the RE since we want to modify its addend.
+    RelocationEntry RECopy = RE;
+    RECopy.Addend += Loc->second.second;
+    Relocations[Loc->second.first].push_back(RECopy);
+  }
 }
 
 uint8_t *RuntimeDyldImpl::createStubFunction(uint8_t *Addr) {
@@ -369,12 +370,12 @@ void RuntimeDyldImpl::resolveRelocationEntry(const RelocationEntry &RE,
       uint8_t *Target = Sections[RE.SectionID].Address + RE.Offset;
       DEBUG(dbgs() << "\tSectionID: " << RE.SectionID
             << " + " << RE.Offset << " (" << format("%p", Target) << ")"
-            << " Data: " << RE.Data
+            << " RelType: " << RE.RelType
             << " Addend: " << RE.Addend
             << "\n");
 
       resolveRelocation(Target, Sections[RE.SectionID].LoadAddress + RE.Offset,
-                        Value, RE.Data, RE.Addend);
+                        Value, RE.RelType, RE.Addend);
   }
 }
 
@@ -385,16 +386,14 @@ void RuntimeDyldImpl::resolveRelocationList(const RelocationList &Relocs,
   }
 }
 
-// resolveSymbols - Resolve any relocations to the specified symbols if
-// we know where it lives.
-void RuntimeDyldImpl::resolveSymbols() {
-  StringMap<RelocationList>::iterator i = SymbolRelocations.begin(),
-                                      e = SymbolRelocations.end();
+void RuntimeDyldImpl::resolveExternalSymbols() {
+  StringMap<RelocationList>::iterator i = ExternalSymbolRelocations.begin(),
+                                      e = ExternalSymbolRelocations.end();
   for (; i != e; i++) {
     StringRef Name = i->first();
     RelocationList &Relocs = i->second;
-    StringMap<SymbolLoc>::const_iterator Loc = SymbolTable.find(Name);
-    if (Loc == SymbolTable.end()) {
+    SymbolTableMap::const_iterator Loc = GlobalSymbolTable.find(Name);
+    if (Loc == GlobalSymbolTable.end()) {
       // This is an external symbol, try to get it address from
       // MemoryManager.
       uint8_t *Addr = (uint8_t*) MemMgr->getPointerToNamedFunction(Name.data(),
@@ -404,15 +403,7 @@ void RuntimeDyldImpl::resolveSymbols() {
               << "\n");
       resolveRelocationList(Relocs, (uintptr_t)Addr);
     } else {
-      // Change the relocation to be section relative rather than symbol
-      // relative and move it to the resolved relocation list.
-      DEBUG(dbgs() << "Resolving symbol '" << Name << "'\n");
-      for (int i = 0, e = Relocs.size(); i != e; ++i) {
-        RelocationEntry Entry = Relocs[i];
-        Entry.Addend += Loc->second.second;
-        Relocations[Loc->second.first].push_back(Entry);
-      }
-      Relocs.clear();
+      report_fatal_error("Expected external symbol");
     }
   }
 }
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
index db6da8c..75bb586 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -55,7 +55,7 @@ public:
 
   const MemoryBuffer& getBuffer() const { return *InputData; }
 
-  // Methods for type inquiry through isa, cast, and dyn_cast
+  // Methods for type inquiry through isa, cast and dyn_cast
   static inline bool classof(const Binary *v) {
     return (isa<ELFObjectFile<target_endianness, is64Bits> >(v)
             && classof(cast<ELFObjectFile<target_endianness, is64Bits> >(v)));
@@ -208,10 +208,9 @@ void RuntimeDyldELF::resolveX86_64Relocation(uint8_t *LocalAddress,
   case ELF::R_X86_64_32:
   case ELF::R_X86_64_32S: {
     Value += Addend;
-    // FIXME: Handle the possibility of this assertion failing
-    assert((Type == ELF::R_X86_64_32 && !(Value & 0xFFFFFFFF00000000ULL)) ||
-           (Type == ELF::R_X86_64_32S &&
-            (Value & 0xFFFFFFFF00000000ULL) == 0xFFFFFFFF00000000ULL));
+    assert((Type == ELF::R_X86_64_32 && (Value <= UINT32_MAX)) ||
+           (Type == ELF::R_X86_64_32S && 
+             ((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
     uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
     uint32_t *Target = reinterpret_cast<uint32_t*>(LocalAddress);
     *Target = TruncatedAddr;
@@ -220,7 +219,7 @@ void RuntimeDyldELF::resolveX86_64Relocation(uint8_t *LocalAddress,
   case ELF::R_X86_64_PC32: {
     uint32_t *Placeholder = reinterpret_cast<uint32_t*>(LocalAddress);
     int64_t RealOffset = *Placeholder + Value + Addend - FinalAddress;
-    assert(RealOffset <= 214783647 && RealOffset >= -214783648);
+    assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
     int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
     *Placeholder = TruncOffset;
     break;
@@ -248,7 +247,7 @@ void RuntimeDyldELF::resolveX86Relocation(uint8_t *LocalAddress,
     }
     default:
       // There are other relocation types, but it appears these are the
-      //  only ones currently used by the LLVM ELF object writer
+      // only ones currently used by the LLVM ELF object writer
       llvm_unreachable("Relocation type not implemented yet!");
       break;
   }
@@ -334,28 +333,31 @@ void RuntimeDyldELF::resolveRelocation(uint8_t *LocalAddress,
 void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel,
                                           ObjectImage &Obj,
                                           ObjSectionToIDMap &ObjSectionToID,
-                                          LocalSymbolMap &Symbols,
+                                          const SymbolTableMap &Symbols,
                                           StubMap &Stubs) {
 
   uint32_t RelType = (uint32_t)(Rel.Type & 0xffffffffL);
   intptr_t Addend = (intptr_t)Rel.AdditionalInfo;
-  RelocationValueRef Value;
-  StringRef TargetName;
   const SymbolRef &Symbol = Rel.Symbol;
+
+  // Obtain the symbol name which is referenced in the relocation
+  StringRef TargetName;
   Symbol.getName(TargetName);
   DEBUG(dbgs() << "\t\tRelType: " << RelType
                << " Addend: " << Addend
                << " TargetName: " << TargetName
                << "\n");
-  // First look the symbol in object file symbols.
-  LocalSymbolMap::iterator lsi = Symbols.find(TargetName.data());
+  RelocationValueRef Value;
+  // First search for the symbol in the local symbol table
+  SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
   if (lsi != Symbols.end()) {
     Value.SectionID = lsi->second.first;
     Value.Addend = lsi->second.second;
   } else {
-    // Second look the symbol in global symbol table.
-    StringMap<SymbolLoc>::iterator gsi = SymbolTable.find(TargetName.data());
-    if (gsi != SymbolTable.end()) {
+    // Search for the symbol in the global symbol table
+    SymbolTableMap::const_iterator gsi =
+        GlobalSymbolTable.find(TargetName.data());
+    if (gsi != GlobalSymbolTable.end()) {
       Value.SectionID = gsi->second.first;
       Value.Addend = gsi->second.second;
     } else {
@@ -366,7 +368,7 @@ void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel,
           // TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
           // and can be changed by another developers. Maybe best way is add
           // a new symbol type ST_Section to SymbolRef and use it.
-          section_iterator si = Obj.end_sections();
+          section_iterator si(Obj.end_sections());
           Symbol.getSection(si);
           if (si == Obj.end_sections())
             llvm_unreachable("Symbol section not found, bad object file format!");
@@ -410,14 +412,24 @@ void RuntimeDyldELF::processRelocationRef(const ObjRelocationInfo &Rel,
       Stubs[Value] = Section.StubOffset;
       uint8_t *StubTargetAddr = createStubFunction(Section.Address +
                                                    Section.StubOffset);
-      AddRelocation(Value, Rel.SectionID,
-                    StubTargetAddr - Section.Address, ELF::R_ARM_ABS32);
+      RelocationEntry RE(Rel.SectionID, StubTargetAddr - Section.Address,
+                         ELF::R_ARM_ABS32, Value.Addend);
+      if (Value.SymbolName)
+        addRelocationForSymbol(RE, Value.SymbolName);
+      else
+        addRelocationForSection(RE, Value.SectionID);
+
       resolveRelocation(Target, (uint64_t)Target, (uint64_t)Section.Address +
                         Section.StubOffset, RelType, 0);
       Section.StubOffset += getMaxStubSize();
     }
-  } else
-    AddRelocation(Value, Rel.SectionID, Rel.Offset, RelType);
+  } else {
+    RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend);
+    if (Value.SymbolName)
+      addRelocationForSymbol(RE, Value.SymbolName);
+    else
+      addRelocationForSection(RE, Value.SectionID);
+  }
 }
 
 bool RuntimeDyldELF::isCompatibleFormat(const MemoryBuffer *InputBuffer) const {
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
index e7f6fab..e413f78 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
@@ -51,7 +51,8 @@ protected:
   virtual void processRelocationRef(const ObjRelocationInfo &Rel,
                                     ObjectImage &Obj,
                                     ObjSectionToIDMap &ObjSectionToID,
-                                    LocalSymbolMap &Symbols, StubMap &Stubs);
+                                    const SymbolTableMap &Symbols,
+                                    StubMap &Stubs);
 
   virtual ObjectImage *createObjectImage(const MemoryBuffer *InputBuffer);
   virtual void handleObjectLoaded(ObjectImage *Obj);
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
index 2dea13f..c38ca69 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
@@ -14,60 +14,83 @@
 #ifndef LLVM_RUNTIME_DYLD_IMPL_H
 #define LLVM_RUNTIME_DYLD_IMPL_H
 
+#include "ObjectImage.h"
 #include "llvm/ExecutionEngine/RuntimeDyld.h"
-#include "llvm/Object/ObjectFile.h"
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/StringMap.h"
-#include "llvm/ADT/Twine.h"
 #include "llvm/ADT/SmallVector.h"
-#include "llvm/Support/Memory.h"
-#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/Support/system_error.h"
-#include "llvm/Support/raw_ostream.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/Object/ObjectFile.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/ErrorHandling.h"
-#include "llvm/ADT/Triple.h"
-#include <map>
 #include "llvm/Support/Format.h"
-#include "ObjectImage.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/system_error.h"
+#include <map>
 
 using namespace llvm;
 using namespace llvm::object;
 
 namespace llvm {
 
+class MemoryBuffer;
+class Twine;
+
+
+/// SectionEntry - represents a section emitted into memory by the dynamic
+/// linker.
 class SectionEntry {
 public:
-  uint8_t* Address;
+  /// Address - address in the linker's memory where the section resides.
+  uint8_t *Address;
+
+  /// Size - section size.
   size_t Size;
-  uint64_t LoadAddress;   // For each section, the address it will be
-                          // considered to live at for relocations. The same
-                          // as the pointer to the above memory block for
-                          // hosted JITs.
-  uintptr_t StubOffset;   // It's used for architecturies with stub
-                          // functions for far relocations like ARM.
-  uintptr_t ObjAddress;   // Section address in object file. It's use for
-                          // calculate MachO relocation addend
-  SectionEntry(uint8_t* address, size_t size, uintptr_t stubOffset,
+
+  /// LoadAddress - the address of the section in the target process's memory.
+  /// Used for situations in which JIT-ed code is being executed in the address
+  /// space of a separate process.  If the code executes in the same address
+  /// space where it was JIT-ed, this just equals Address.
+  uint64_t LoadAddress;
+
+  /// StubOffset - used for architectures with stub functions for far
+  /// relocations (like ARM).
+  uintptr_t StubOffset;
+
+  /// ObjAddress - address of the section in the in-memory object file.  Used
+  /// for calculating relocations in some object formats (like MachO).
+  uintptr_t ObjAddress;
+
+  SectionEntry(uint8_t *address, size_t size, uintptr_t stubOffset,
                uintptr_t objAddress)
     : Address(address), Size(size), LoadAddress((uintptr_t)address),
       StubOffset(stubOffset), ObjAddress(objAddress) {}
 };
 
+/// RelocationEntry - used to represent relocations internally in the dynamic
+/// linker.
 class RelocationEntry {
 public:
-  unsigned    SectionID;  // Section the relocation is contained in.
-  uintptr_t   Offset;     // Offset into the section for the relocation.
-  uint32_t    Data;       // Relocatino data. Including type of relocation
-                          // and another flags and parameners from
-  intptr_t    Addend;     // Addend encoded in the instruction itself, if any,
-                          // plus the offset into the source section for
-                          // the symbol once the relocation is resolvable.
-  RelocationEntry(unsigned id, uint64_t offset, uint32_t data, int64_t addend)
-    : SectionID(id), Offset(offset), Data(data), Addend(addend) {}
+  /// SectionID - the section this relocation points to.
+  unsigned SectionID;
+
+  /// Offset - offset into the section.
+  uintptr_t Offset;
+
+  /// RelType - relocation type.
+  uint32_t RelType;
+
+  /// Addend - the relocation addend encoded in the instruction itself.  Also
+  /// used to make a relocation section relative instead of symbol relative.
+  intptr_t Addend;
+
+  RelocationEntry(unsigned id, uint64_t offset, uint32_t type, int64_t addend)
+    : SectionID(id), Offset(offset), RelType(type), Addend(addend) {}
 };
 
-// Raw relocation data from object file
+/// ObjRelocationInfo - relocation information as read from the object file.
+/// Used to pass around data taken from object::RelocationRef, together with
+/// the section to which the relocation points (represented by a SectionID).
 class ObjRelocationInfo {
 public:
   unsigned  SectionID;
@@ -97,7 +120,8 @@ protected:
   // The MemoryManager to load objects into.
   RTDyldMemoryManager *MemMgr;
 
-  // A list of emmitted sections.
+  // A list of all sections emitted by the dynamic linker.  These sections are
+  // referenced in the code by means of their index in this list - SectionID.
   typedef SmallVector<SectionEntry, 64> SectionList;
   SectionList Sections;
 
@@ -105,11 +129,11 @@ protected:
   // references it.
   typedef std::map<SectionRef, unsigned> ObjSectionToIDMap;
 
-  // Master symbol table. As modules are loaded and external symbols are
-  // resolved, their addresses are stored here as a SectionID/Offset pair.
+  // A global symbol table for symbols from all loaded modules.  Maps the
+  // symbol name to a (SectionID, offset in section) pair.
   typedef std::pair<unsigned, uintptr_t> SymbolLoc;
-  StringMap<SymbolLoc> SymbolTable;
-  typedef DenseMap<const char*, SymbolLoc> LocalSymbolMap;
+  typedef StringMap<SymbolLoc> SymbolTableMap;
+  SymbolTableMap GlobalSymbolTable;
 
   // Keep a map of common symbols to their sizes
   typedef std::map<SymbolRef, unsigned> CommonSymbolMap;
@@ -121,12 +145,14 @@ protected:
   // in the relocation list where it's stored.
   typedef SmallVector<RelocationEntry, 64> RelocationList;
   // Relocations to sections already loaded. Indexed by SectionID which is the
-  // source of the address. The target where the address will be writen is
+  // source of the address. The target where the address will be written is
   // SectionID/Offset in the relocation itself.
   DenseMap<unsigned, RelocationList> Relocations;
-  // Relocations to external symbols that are not yet resolved.
-  // Indexed by symbol name.
-  StringMap<RelocationList> SymbolRelocations;
+
+  // Relocations to external symbols that are not yet resolved.  Symbols are
+  // external when they aren't found in the global symbol table of all loaded
+  // modules.  This map is indexed by symbol name.
+  StringMap<RelocationList> ExternalSymbolRelocations;
 
   typedef std::map<RelocationValueRef, uintptr_t> StubMap;
 
@@ -153,16 +179,17 @@ protected:
     return (uint8_t*)Sections[SectionID].Address;
   }
 
-  /// \brief Emits a section containing common symbols.
-  /// \return SectionID.
-  unsigned emitCommonSymbols(ObjectImage &Obj,
-                             const CommonSymbolMap &Map,
-                             uint64_t TotalSize,
-                             LocalSymbolMap &Symbols);
+  /// \brief Given the common symbols discovered in the object file, emit a
+  /// new section for them and update the symbol mappings in the object and
+  /// symbol table.
+  void emitCommonSymbols(ObjectImage &Obj,
+                         const CommonSymbolMap &CommonSymbols,
+                         uint64_t TotalSize,
+                         SymbolTableMap &SymbolTable);
 
   /// \brief Emits section data from the object file to the MemoryManager.
   /// \param IsCode if it's true then allocateCodeSection() will be
-  ///        used for emmits, else allocateDataSection() will be used.
+  ///        used for emits, else allocateDataSection() will be used.
   /// \return SectionID.
   unsigned emitSection(ObjectImage &Obj,
                        const SectionRef &Section,
@@ -178,10 +205,12 @@ protected:
                              bool IsCode,
                              ObjSectionToIDMap &LocalSections);
 
-  /// \brief If Value.SymbolName is NULL then store relocation to the
-  ///        Relocations, else store it in the SymbolRelocations.
-  void AddRelocation(const RelocationValueRef &Value, unsigned SectionID,
-                     uintptr_t Offset, uint32_t RelType);
+  // \brief Add a relocation entry that uses the given section.
+  void addRelocationForSection(const RelocationEntry &RE, unsigned SectionID);
+
+  // \brief Add a relocation entry that uses the given symbol.  This symbol may
+  // be found in the global symbol table, or it may be external.
+  void addRelocationForSymbol(const RelocationEntry &RE, StringRef SymbolName);
 
   /// \brief Emits long jump instruction to Addr.
   /// \return Pointer to the memory area for emitting target address.
@@ -203,14 +232,16 @@ protected:
                                  uint32_t Type,
                                  int64_t Addend) = 0;
 
-  /// \brief Parses the object file relocation and store it to Relocations
-  ///        or SymbolRelocations. Its depend from object file type.
+  /// \brief Parses the object file relocation and stores it to Relocations
+  ///        or SymbolRelocations (this depends on the object file type).
   virtual void processRelocationRef(const ObjRelocationInfo &Rel,
                                     ObjectImage &Obj,
                                     ObjSectionToIDMap &ObjSectionToID,
-                                    LocalSymbolMap &Symbols, StubMap &Stubs) = 0;
+                                    const SymbolTableMap &Symbols,
+                                    StubMap &Stubs) = 0;
 
-  void resolveSymbols();
+  /// \brief Resolve relocations to external symbols.
+  void resolveExternalSymbols();
   virtual ObjectImage *createObjectImage(const MemoryBuffer *InputBuffer);
   virtual void handleObjectLoaded(ObjectImage *Obj)
   {
@@ -228,9 +259,9 @@ public:
   void *getSymbolAddress(StringRef Name) {
     // FIXME: Just look up as a function for now. Overly simple of course.
     // Work in progress.
-    if (SymbolTable.find(Name) == SymbolTable.end())
+    if (GlobalSymbolTable.find(Name) == GlobalSymbolTable.end())
       return 0;
-    SymbolLoc Loc = SymbolTable.lookup(Name);
+    SymbolLoc Loc = GlobalSymbolTable.lookup(Name);
     return getSectionAddress(Loc.first) + Loc.second;
   }
 
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
index b7f515d..0e3a9d4 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
@@ -30,7 +30,8 @@ void RuntimeDyldMachO::resolveRelocation(uint8_t *LocalAddress,
   unsigned MachoType = (Type >> 28) & 0xf;
   unsigned Size = 1 << ((Type >> 25) & 3);
 
-  DEBUG(dbgs() << "resolveRelocation LocalAddress: " << format("%p", LocalAddress)
+  DEBUG(dbgs() << "resolveRelocation LocalAddress: " 
+        << format("%p", LocalAddress)
         << " FinalAddress: " << format("%p", FinalAddress)
         << " Value: " << format("%p", Value)
         << " Addend: " << Addend
@@ -53,12 +54,12 @@ void RuntimeDyldMachO::resolveRelocation(uint8_t *LocalAddress,
     break;
   case Triple::x86:
     resolveI386Relocation(LocalAddress,
-                                 FinalAddress,
-                                 (uintptr_t)Value,
-                                 isPCRel,
-                                 Type,
-                                 Size,
-                                 Addend);
+                          FinalAddress,
+                          (uintptr_t)Value,
+                          isPCRel,
+                          Type,
+                          Size,
+                          Addend);
     break;
   case Triple::arm:    // Fall through.
   case Triple::thumb:
@@ -73,14 +74,13 @@ void RuntimeDyldMachO::resolveRelocation(uint8_t *LocalAddress,
   }
 }
 
-bool RuntimeDyldMachO::
-resolveI386Relocation(uint8_t *LocalAddress,
-                      uint64_t FinalAddress,
-                      uint64_t Value,
-                      bool isPCRel,
-                      unsigned Type,
-                      unsigned Size,
-                      int64_t Addend) {
+bool RuntimeDyldMachO::resolveI386Relocation(uint8_t *LocalAddress,
+                                             uint64_t FinalAddress,
+                                             uint64_t Value,
+                                             bool isPCRel,
+                                             unsigned Type,
+                                             unsigned Size,
+                                             int64_t Addend) {
   if (isPCRel)
     Value -= FinalAddress + 4; // see resolveX86_64Relocation
 
@@ -102,14 +102,13 @@ resolveI386Relocation(uint8_t *LocalAddress,
   }
 }
 
-bool RuntimeDyldMachO::
-resolveX86_64Relocation(uint8_t *LocalAddress,
-                        uint64_t FinalAddress,
-                        uint64_t Value,
-                        bool isPCRel,
-                        unsigned Type,
-                        unsigned Size,
-                        int64_t Addend) {
+bool RuntimeDyldMachO::resolveX86_64Relocation(uint8_t *LocalAddress,
+                                               uint64_t FinalAddress,
+                                               uint64_t Value,
+                                               bool isPCRel,
+                                               unsigned Type,
+                                               unsigned Size,
+                                               int64_t Addend) {
   // If the relocation is PC-relative, the value to be encoded is the
   // pointer difference.
   if (isPCRel)
@@ -144,14 +143,13 @@ resolveX86_64Relocation(uint8_t *LocalAddress,
   }
 }
 
-bool RuntimeDyldMachO::
-resolveARMRelocation(uint8_t *LocalAddress,
-                     uint64_t FinalAddress,
-                     uint64_t Value,
-                     bool isPCRel,
-                     unsigned Type,
-                     unsigned Size,
-                     int64_t Addend) {
+bool RuntimeDyldMachO::resolveARMRelocation(uint8_t *LocalAddress,
+                                            uint64_t FinalAddress,
+                                            uint64_t Value,
+                                            bool isPCRel,
+                                            unsigned Type,
+                                            unsigned Size,
+                                            int64_t Addend) {
   // If the relocation is PC-relative, the value to be encoded is the
   // pointer difference.
   if (isPCRel) {
@@ -207,7 +205,7 @@ resolveARMRelocation(uint8_t *LocalAddress,
 void RuntimeDyldMachO::processRelocationRef(const ObjRelocationInfo &Rel,
                                             ObjectImage &Obj,
                                             ObjSectionToIDMap &ObjSectionToID,
-                                            LocalSymbolMap &Symbols,
+                                            const SymbolTableMap &Symbols,
                                             StubMap &Stubs) {
 
   uint32_t RelType = (uint32_t) (Rel.Type & 0xffffffffL);
@@ -217,18 +215,19 @@ void RuntimeDyldMachO::processRelocationRef(const ObjRelocationInfo &Rel,
 
   bool isExtern = (RelType >> 27) & 1;
   if (isExtern) {
+    // Obtain the symbol name which is referenced in the relocation
     StringRef TargetName;
     const SymbolRef &Symbol = Rel.Symbol;
     Symbol.getName(TargetName);
-    // First look the symbol in object file symbols.
-    LocalSymbolMap::iterator lsi = Symbols.find(TargetName.data());
+    // First search for the symbol in the local symbol table
+    SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
     if (lsi != Symbols.end()) {
       Value.SectionID = lsi->second.first;
       Value.Addend = lsi->second.second;
     } else {
-      // Second look the symbol in global symbol table.
-      StringMap<SymbolLoc>::iterator gsi = SymbolTable.find(TargetName.data());
-      if (gsi != SymbolTable.end()) {
+      // Search for the symbol in the global symbol table
+      SymbolTableMap::const_iterator gsi = GlobalSymbolTable.find(TargetName.data());
+      if (gsi != GlobalSymbolTable.end()) {
         Value.SectionID = gsi->second.first;
         Value.Addend = gsi->second.second;
       } else
@@ -249,8 +248,8 @@ void RuntimeDyldMachO::processRelocationRef(const ObjRelocationInfo &Rel,
     Value.SectionID = findOrEmitSection(Obj, *si, true, ObjSectionToID);
     Value.Addend = *(const intptr_t *)Target;
     if (Value.Addend) {
-      // The MachO addend is offset from the current section, we need set it
-      // as offset from destination section
+      // The MachO addend is an offset from the current section.  We need it
+      // to be an offset from the destination section
       Value.Addend += Section.ObjAddress - Sections[Value.SectionID].ObjAddress;
     }
   }
@@ -269,19 +268,29 @@ void RuntimeDyldMachO::processRelocationRef(const ObjRelocationInfo &Rel,
       Stubs[Value] = Section.StubOffset;
       uint8_t *StubTargetAddr = createStubFunction(Section.Address +
                                                    Section.StubOffset);
-      AddRelocation(Value, Rel.SectionID, StubTargetAddr - Section.Address,
-                    macho::RIT_Vanilla);
+      RelocationEntry RE(Rel.SectionID, StubTargetAddr - Section.Address,
+                         macho::RIT_Vanilla, Value.Addend);
+      if (Value.SymbolName)
+        addRelocationForSymbol(RE, Value.SymbolName);
+      else
+        addRelocationForSection(RE, Value.SectionID);
       resolveRelocation(Target, (uint64_t)Target,
                         (uint64_t)Section.Address + Section.StubOffset,
                         RelType, 0);
       Section.StubOffset += getMaxStubSize();
     }
-  } else
-    AddRelocation(Value, Rel.SectionID, Rel.Offset, RelType);
+  } else {
+    RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend);
+    if (Value.SymbolName)
+      addRelocationForSymbol(RE, Value.SymbolName);
+    else
+      addRelocationForSection(RE, Value.SectionID);
+  }
 }
 
 
-bool RuntimeDyldMachO::isCompatibleFormat(const MemoryBuffer *InputBuffer) const {
+bool RuntimeDyldMachO::isCompatibleFormat(
+        const MemoryBuffer *InputBuffer) const {
   StringRef Magic = InputBuffer->getBuffer().slice(0, 4);
   if (Magic == "\xFE\xED\xFA\xCE") return true;
   if (Magic == "\xCE\xFA\xED\xFE") return true;
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.h
index 418d130..707664c 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.h
@@ -51,7 +51,8 @@ protected:
   virtual void processRelocationRef(const ObjRelocationInfo &Rel,
                                     ObjectImage &Obj,
                                     ObjSectionToIDMap &ObjSectionToID,
-                                    LocalSymbolMap &Symbols, StubMap &Stubs);
+                                    const SymbolTableMap &Symbols,
+                                    StubMap &Stubs);
 
 public:
   virtual void resolveRelocation(uint8_t *LocalAddress,
diff --git a/lib/ExecutionEngine/TargetSelect.cpp b/lib/ExecutionEngine/TargetSelect.cpp
index 42364f9..7cdd669 100644
--- a/lib/ExecutionEngine/TargetSelect.cpp
+++ b/lib/ExecutionEngine/TargetSelect.cpp
@@ -26,11 +26,7 @@
 using namespace llvm;
 
 TargetMachine *EngineBuilder::selectTarget() {
-  StringRef MArch = "";
-  StringRef MCPU = "";
-  SmallVector<std::string, 1> MAttrs;
-  Triple TT(M->getTargetTriple());
-
+  Triple TT(LLVM_HOSTTRIPLE);
   return selectTarget(TT, MArch, MCPU, MAttrs);
 }
 
@@ -56,8 +52,9 @@ TargetMachine *EngineBuilder::selectTarget(const Triple &TargetTriple,
     }
 
     if (!TheTarget) {
-      *ErrorStr = "No available targets are compatible with this -march, "
-        "see -version for the available targets.\n";
+      if (ErrorStr)
+        *ErrorStr = "No available targets are compatible with this -march, "
+                    "see -version for the available targets.\n";
       return 0;
     }