MFC 261991:

Upgrade our copy of llvm/clang to 3.4 release.  This version supports
all of the features in the current working draft of the upcoming C++
standard, provisionally named C++1y.

The code generator's performance is greatly increased, and the loop
auto-vectorizer is now enabled at -Os and -O2 in addition to -O3.  The
PowerPC backend has made several major improvements to code generation
quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ
backends have all seen major feature work.

Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.4/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html>

MFC 262121 (by emaste):

Update lldb for clang/llvm 3.4 import

This commit largely restores the lldb source to the upstream r196259
snapshot with the addition of threaded inferior support and a few bug
fixes.

Specific upstream lldb revisions restored include:
   SVN      git
  181387  779e6ac
  181703  7bef4e2
  182099  b31044e
  182650  f2dcf35
  182683  0d91b80
  183862  15c1774
  183929  99447a6
  184177  0b2934b
  184948  4dc3761
  184954  007e7bc
  186990  eebd175

Sponsored by:	DARPA, AFRL

MFC 262186 (by emaste):

Fix mismerge in r262121

A break statement was lost in the merge.  The error had no functional
impact, but restore it to reduce the diff against upstream.

MFC 262303:

Pull in r197521 from upstream clang trunk (by rdivacky):

  Use the integrated assembler by default on FreeBSD/ppc and ppc64.

Requested by:	jhibbits

MFC 262611:

Pull in r196874 from upstream llvm trunk:

  Fix a crash that occurs when PWD is invalid.

  MCJIT needs to be able to run in hostile environments, even when PWD
  is invalid. There's no need to crash MCJIT in this case.

  The obvious fix is to simply leave MCContext's CompilationDir empty
  when PWD can't be determined. This way, MCJIT clients,
  and other clients that link with LLVM don't need a valid working directory.

  If we do want to guarantee valid CompilationDir, that should be done
  only for clients of getCompilationDir(). This is as simple as checking
  for an empty string.

  The only current use of getCompilationDir is EmitGenDwarfInfo, which
  won't conceivably run with an invalid working dir. However, in the
  purely hypothetically and untestable case that this happens, the
  AT_comp_dir will be omitted from the compilation_unit DIE.

This should help fix assertions occurring with ports-mgmt/tinderbox,
when it is using jails, and sometimes invalidates clang's current
working directory.

Reported by:	decke

MFC 262809:

Pull in r203007 from upstream clang trunk:

  Don't produce an alias between destructors with different calling conventions.

  Fixes pr19007.

(Please note that is an LLVM PR identifier, not a FreeBSD one.)

This should fix Firefox and/or libxul crashes (due to problems with
regparm/stdcall calling conventions) on i386.

Reported by:	multiple users on freebsd-current
PR:		bin/187103

MFC 263048:

Repair recognition of "CC" as an alias for the C++ compiler, since it
was silently broken by upstream for a Windows-specific use-case.

Apparently some versions of CMake still rely on this archaic feature...

Reported by:	rakuco

MFC 263049:

Garbage collect the old way of adding the libstdc++ include directories
in clang's InitHeaderSearch.cpp.  This has been superseded by David
Chisnall's commit in r255321.

Moreover, if libc++ is used, the libstdc++ include directories should
not be in the search path at all.  These directories are now only used
if you pass -stdlib=libstdc++.

1 files changed, 391 insertions, 71 deletions

diff --git a/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
index d4d84d3..f2c69fc 100644
--- a/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
+++ b/contrib/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -22,7 +22,7 @@
 #include "llvm/ADT/Triple.h"
 #include "llvm/ExecutionEngine/ObjectBuffer.h"
 #include "llvm/ExecutionEngine/ObjectImage.h"
-#include "llvm/Object/ELF.h"
+#include "llvm/Object/ELFObjectFile.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Support/ELF.h"
 using namespace llvm;
@@ -151,12 +151,31 @@ void DyldELFObject<ELFT>::updateSymbolAddress(const SymbolRef &SymRef,
 
 namespace llvm {
 
-StringRef RuntimeDyldELF::getEHFrameSection() {
-  for (int i = 0, e = Sections.size(); i != e; ++i) {
-    if (Sections[i].Name == ".eh_frame")
-      return StringRef((const char*)Sections[i].Address, Sections[i].Size);
+void RuntimeDyldELF::registerEHFrames() {
+  if (!MemMgr)
+    return;
+  for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
+    SID EHFrameSID = UnregisteredEHFrameSections[i];
+    uint8_t *EHFrameAddr = Sections[EHFrameSID].Address;
+    uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress;
+    size_t EHFrameSize = Sections[EHFrameSID].Size;
+    MemMgr->registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
+    RegisteredEHFrameSections.push_back(EHFrameSID);
   }
-  return StringRef();
+  UnregisteredEHFrameSections.clear();
+}
+
+void RuntimeDyldELF::deregisterEHFrames() {
+  if (!MemMgr)
+    return;
+  for (int i = 0, e = RegisteredEHFrameSections.size(); i != e; ++i) {
+    SID EHFrameSID = RegisteredEHFrameSections[i];
+    uint8_t *EHFrameAddr = Sections[EHFrameSID].Address;
+    uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress;
+    size_t EHFrameSize = Sections[EHFrameSID].Size;
+    MemMgr->deregisterEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
+  }
+  RegisteredEHFrameSections.clear();
 }
 
 ObjectImage *RuntimeDyldELF::createObjectImage(ObjectBuffer *Buffer) {
@@ -202,7 +221,8 @@ void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
                                              uint64_t Offset,
                                              uint64_t Value,
                                              uint32_t Type,
-                                             int64_t Addend) {
+                                             int64_t  Addend,
+                                             uint64_t SymOffset) {
   switch (Type) {
   default:
     llvm_unreachable("Relocation type not implemented yet!");
@@ -227,6 +247,21 @@ void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
                  << " at " << format("%p\n",Target));
     break;
   }
+  case ELF::R_X86_64_GOTPCREL: {
+    // findGOTEntry returns the 'G + GOT' part of the relocation calculation
+    // based on the load/target address of the GOT (not the current/local addr).
+    uint64_t GOTAddr = findGOTEntry(Value, SymOffset);
+    uint32_t *Target = reinterpret_cast<uint32_t*>(Section.Address + Offset);
+    uint64_t  FinalAddress = Section.LoadAddress + Offset;
+    // The processRelocationRef method combines the symbol offset and the addend
+    // and in most cases that's what we want.  For this relocation type, we need
+    // the raw addend, so we subtract the symbol offset to get it.
+    int64_t RealOffset = GOTAddr + Addend - SymOffset - FinalAddress;
+    assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
+    int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
+    *Target = TruncOffset;
+    break;
+  }
   case ELF::R_X86_64_PC32: {
     // Get the placeholder value from the generated object since
     // a previous relocation attempt may have overwritten the loaded version
@@ -240,6 +275,16 @@ void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
     *Target = TruncOffset;
     break;
   }
+  case ELF::R_X86_64_PC64: {
+    // Get the placeholder value from the generated object since
+    // a previous relocation attempt may have overwritten the loaded version
+    uint64_t *Placeholder = reinterpret_cast<uint64_t*>(Section.ObjAddress
+                                                                   + Offset);
+    uint64_t *Target = reinterpret_cast<uint64_t*>(Section.Address + Offset);
+    uint64_t  FinalAddress = Section.LoadAddress + Offset;
+    *Target = *Placeholder + Value + Addend - FinalAddress;
+    break;
+  }
   }
 }
 
@@ -302,9 +347,9 @@ void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
     *TargetPtr = Value + Addend;
     break;
   }
-  case ELF::R_AARCH64_PREL32: { // test-shift.ll (.eh_frame)
+  case ELF::R_AARCH64_PREL32: {
     uint64_t Result = Value + Addend - FinalAddress;
-    assert(static_cast<int64_t>(Result) >= INT32_MIN && 
+    assert(static_cast<int64_t>(Result) >= INT32_MIN &&
            static_cast<int64_t>(Result) <= UINT32_MAX);
     *TargetPtr = static_cast<uint32_t>(Result & 0xffffffffU);
     break;
@@ -316,41 +361,62 @@ void RuntimeDyldELF::resolveAArch64Relocation(const SectionEntry &Section,
     uint64_t BranchImm = Value + Addend - FinalAddress;
 
     // "Check that -2^27 <= result < 2^27".
-    assert(-(1LL << 27) <= static_cast<int64_t>(BranchImm) && 
+    assert(-(1LL << 27) <= static_cast<int64_t>(BranchImm) &&
            static_cast<int64_t>(BranchImm) < (1LL << 27));
+
+    // AArch64 code is emitted with .rela relocations. The data already in any
+    // bits affected by the relocation on entry is garbage.
+    *TargetPtr &= 0xfc000000U;
     // Immediate goes in bits 25:0 of B and BL.
     *TargetPtr |= static_cast<uint32_t>(BranchImm & 0xffffffcU) >> 2;
     break;
   }
   case ELF::R_AARCH64_MOVW_UABS_G3: {
     uint64_t Result = Value + Addend;
+
+    // AArch64 code is emitted with .rela relocations. The data already in any
+    // bits affected by the relocation on entry is garbage.
+    *TargetPtr &= 0xffe0001fU;
     // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
     *TargetPtr |= Result >> (48 - 5);
-    // Shift is "lsl #48", in bits 22:21
-    *TargetPtr |= 3 << 21;
+    // Shift must be "lsl #48", in bits 22:21
+    assert((*TargetPtr >> 21 & 0x3) == 3 && "invalid shift for relocation");
     break;
   }
   case ELF::R_AARCH64_MOVW_UABS_G2_NC: {
     uint64_t Result = Value + Addend;
+
+    // AArch64 code is emitted with .rela relocations. The data already in any
+    // bits affected by the relocation on entry is garbage.
+    *TargetPtr &= 0xffe0001fU;
     // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
     *TargetPtr |= ((Result & 0xffff00000000ULL) >> (32 - 5));
-    // Shift is "lsl #32", in bits 22:21
-    *TargetPtr |= 2 << 21;
+    // Shift must be "lsl #32", in bits 22:21
+    assert((*TargetPtr >> 21 & 0x3) == 2 && "invalid shift for relocation");
     break;
   }
   case ELF::R_AARCH64_MOVW_UABS_G1_NC: {
     uint64_t Result = Value + Addend;
+
+    // AArch64 code is emitted with .rela relocations. The data already in any
+    // bits affected by the relocation on entry is garbage.
+    *TargetPtr &= 0xffe0001fU;
     // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
     *TargetPtr |= ((Result & 0xffff0000U) >> (16 - 5));
-    // Shift is "lsl #16", in bits 22:21
-    *TargetPtr |= 1 << 21;
+    // Shift must be "lsl #16", in bits 22:2
+    assert((*TargetPtr >> 21 & 0x3) == 1 && "invalid shift for relocation");
     break;
   }
   case ELF::R_AARCH64_MOVW_UABS_G0_NC: {
     uint64_t Result = Value + Addend;
+
+    // AArch64 code is emitted with .rela relocations. The data already in any
+    // bits affected by the relocation on entry is garbage.
+    *TargetPtr &= 0xffe0001fU;
     // Immediate goes in bits 20:5 of MOVZ/MOVK instruction
     *TargetPtr |= ((Result & 0xffffU) << 5);
-    // Shift is "lsl #0", in bits 22:21. No action needed.
+    // Shift must be "lsl #0", in bits 22:21.
+    assert((*TargetPtr >> 21 & 0x3) == 0 && "invalid shift for relocation");
     break;
   }
   }
@@ -362,6 +428,8 @@ void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
                                           uint32_t Type,
                                           int32_t Addend) {
   // TODO: Add Thumb relocations.
+  uint32_t *Placeholder = reinterpret_cast<uint32_t*>(Section.ObjAddress +
+                                                      Offset);
   uint32_t* TargetPtr = (uint32_t*)(Section.Address + Offset);
   uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
   Value += Addend;
@@ -380,44 +448,51 @@ void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
 
   // Write a 32bit value to relocation address, taking into account the
   // implicit addend encoded in the target.
-  case ELF::R_ARM_TARGET1 :
-  case ELF::R_ARM_ABS32 :
-    *TargetPtr += Value;
+  case ELF::R_ARM_TARGET1:
+  case ELF::R_ARM_ABS32:
+    *TargetPtr = *Placeholder + Value;
     break;
-
   // Write first 16 bit of 32 bit value to the mov instruction.
   // Last 4 bit should be shifted.
-  case ELF::R_ARM_MOVW_ABS_NC :
+  case ELF::R_ARM_MOVW_ABS_NC:
     // We are not expecting any other addend in the relocation address.
     // Using 0x000F0FFF because MOVW has its 16 bit immediate split into 2
     // non-contiguous fields.
-    assert((*TargetPtr & 0x000F0FFF) == 0);
+    assert((*Placeholder & 0x000F0FFF) == 0);
     Value = Value & 0xFFFF;
-    *TargetPtr |= Value & 0xFFF;
+    *TargetPtr = *Placeholder | (Value & 0xFFF);
     *TargetPtr |= ((Value >> 12) & 0xF) << 16;
     break;
-
   // Write last 16 bit of 32 bit value to the mov instruction.
   // Last 4 bit should be shifted.
-  case ELF::R_ARM_MOVT_ABS :
+  case ELF::R_ARM_MOVT_ABS:
     // We are not expecting any other addend in the relocation address.
     // Use 0x000F0FFF for the same reason as R_ARM_MOVW_ABS_NC.
-    assert((*TargetPtr & 0x000F0FFF) == 0);
+    assert((*Placeholder & 0x000F0FFF) == 0);
+
     Value = (Value >> 16) & 0xFFFF;
-    *TargetPtr |= Value & 0xFFF;
+    *TargetPtr = *Placeholder | (Value & 0xFFF);
     *TargetPtr |= ((Value >> 12) & 0xF) << 16;
     break;
-
   // Write 24 bit relative value to the branch instruction.
   case ELF::R_ARM_PC24 :    // Fall through.
   case ELF::R_ARM_CALL :    // Fall through.
-  case ELF::R_ARM_JUMP24 :
+  case ELF::R_ARM_JUMP24: {
     int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
     RelValue = (RelValue & 0x03FFFFFC) >> 2;
+    assert((*TargetPtr & 0xFFFFFF) == 0xFFFFFE);
     *TargetPtr &= 0xFF000000;
     *TargetPtr |= RelValue;
     break;
   }
+  case ELF::R_ARM_PRIVATE_0:
+    // This relocation is reserved by the ARM ELF ABI for internal use. We
+    // appropriate it here to act as an R_ARM_ABS32 without any addend for use
+    // in the stubs created during JIT (which can't put an addend into the
+    // original object file).
+    *TargetPtr = Value;
+    break;
+  }
 }
 
 void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
@@ -425,6 +500,8 @@ void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
                                            uint32_t Value,
                                            uint32_t Type,
                                            int32_t Addend) {
+  uint32_t *Placeholder = reinterpret_cast<uint32_t*>(Section.ObjAddress +
+                                                      Offset);
   uint32_t* TargetPtr = (uint32_t*)(Section.Address + Offset);
   Value += Addend;
 
@@ -442,19 +519,30 @@ void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
     llvm_unreachable("Not implemented relocation type!");
     break;
   case ELF::R_MIPS_32:
-    *TargetPtr = Value + (*TargetPtr);
+    *TargetPtr = Value + (*Placeholder);
     break;
   case ELF::R_MIPS_26:
-    *TargetPtr = ((*TargetPtr) & 0xfc000000) | (( Value & 0x0fffffff) >> 2);
+    *TargetPtr = ((*Placeholder) & 0xfc000000) | (( Value & 0x0fffffff) >> 2);
     break;
   case ELF::R_MIPS_HI16:
     // Get the higher 16-bits. Also add 1 if bit 15 is 1.
-    Value += ((*TargetPtr) & 0x0000ffff) << 16;
+    Value += ((*Placeholder) & 0x0000ffff) << 16;
+    *TargetPtr = ((*Placeholder) & 0xffff0000) |
+                 (((Value + 0x8000) >> 16) & 0xffff);
+    break;
+  case ELF::R_MIPS_LO16:
+    Value += ((*Placeholder) & 0x0000ffff);
+    *TargetPtr = ((*Placeholder) & 0xffff0000) | (Value & 0xffff);
+    break;
+  case ELF::R_MIPS_UNUSED1:
+    // Similar to ELF::R_ARM_PRIVATE_0, R_MIPS_UNUSED1 and R_MIPS_UNUSED2
+    // are used for internal JIT purpose. These relocations are similar to
+    // R_MIPS_HI16 and R_MIPS_LO16, but they do not take any addend into
+    // account.
     *TargetPtr = ((*TargetPtr) & 0xffff0000) |
                  (((Value + 0x8000) >> 16) & 0xffff);
     break;
-   case ELF::R_MIPS_LO16:
-    Value += ((*TargetPtr) & 0x0000ffff);
+  case ELF::R_MIPS_UNUSED2:
     *TargetPtr = ((*TargetPtr) & 0xffff0000) | (Value & 0xffff);
     break;
    }
@@ -499,9 +587,13 @@ void RuntimeDyldELF::findOPDEntrySection(ObjectImage &Obj,
   error_code err;
   for (section_iterator si = Obj.begin_sections(),
      se = Obj.end_sections(); si != se; si.increment(err)) {
-    StringRef SectionName;
-    check(si->getName(SectionName));
-    if (SectionName != ".opd")
+    section_iterator RelSecI = si->getRelocatedSection();
+    if (RelSecI == Obj.end_sections())
+      continue;
+
+    StringRef RelSectionName;
+    check(RelSecI->getName(RelSectionName));
+    if (RelSectionName != ".opd")
       continue;
 
     for (relocation_iterator i = si->begin_relocations(),
@@ -517,12 +609,11 @@ void RuntimeDyldELF::findOPDEntrySection(ObjectImage &Obj,
         continue;
       }
 
-      SymbolRef TargetSymbol;
       uint64_t TargetSymbolOffset;
-      int64_t TargetAdditionalInfo;
-      check(i->getSymbol(TargetSymbol));
+      symbol_iterator TargetSymbol = i->getSymbol();
       check(i->getOffset(TargetSymbolOffset));
-      check(i->getAdditionalInfo(TargetAdditionalInfo));
+      int64_t Addend;
+      check(getELFRelocationAddend(*i, Addend));
 
       i = i.increment(err);
       if (i == e)
@@ -538,13 +629,13 @@ void RuntimeDyldELF::findOPDEntrySection(ObjectImage &Obj,
       // Finally compares the Symbol value and the target symbol offset
       // to check if this .opd entry refers to the symbol the relocation
       // points to.
-      if (Rel.Addend != (intptr_t)TargetSymbolOffset)
+      if (Rel.Addend != (int64_t)TargetSymbolOffset)
         continue;
 
       section_iterator tsi(Obj.end_sections());
-      check(TargetSymbol.getSection(tsi));
+      check(TargetSymbol->getSection(tsi));
       Rel.SectionID = findOrEmitSection(Obj, (*tsi), true, LocalSections);
-      Rel.Addend = (intptr_t)TargetAdditionalInfo;
+      Rel.Addend = (intptr_t)Addend;
       return;
     }
   }
@@ -688,20 +779,42 @@ void RuntimeDyldELF::resolveSystemZRelocation(const SectionEntry &Section,
   }
 }
 
+// The target location for the relocation is described by RE.SectionID and
+// RE.Offset.  RE.SectionID can be used to find the SectionEntry.  Each
+// SectionEntry has three members describing its location.
+// SectionEntry::Address is the address at which the section has been loaded
+// into memory in the current (host) process.  SectionEntry::LoadAddress is the
+// address that the section will have in the target process.
+// SectionEntry::ObjAddress is the address of the bits for this section in the
+// original emitted object image (also in the current address space).
+//
+// Relocations will be applied as if the section were loaded at
+// SectionEntry::LoadAddress, but they will be applied at an address based
+// on SectionEntry::Address.  SectionEntry::ObjAddress will be used to refer to
+// Target memory contents if they are required for value calculations.
+//
+// The Value parameter here is the load address of the symbol for the
+// relocation to be applied.  For relocations which refer to symbols in the
+// current object Value will be the LoadAddress of the section in which
+// the symbol resides (RE.Addend provides additional information about the
+// symbol location).  For external symbols, Value will be the address of the
+// symbol in the target address space.
 void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
-				       uint64_t Value) {
+                                       uint64_t Value) {
   const SectionEntry &Section = Sections[RE.SectionID];
-  return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend);
+  return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
+                           RE.SymOffset);
 }
 
 void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
                                        uint64_t Offset,
                                        uint64_t Value,
                                        uint32_t Type,
-                                       int64_t Addend) {
+                                       int64_t  Addend,
+                                       uint64_t SymOffset) {
   switch (Arch) {
   case Triple::x86_64:
-    resolveX86_64Relocation(Section, Offset, Value, Type, Addend);
+    resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
     break;
   case Triple::x86:
     resolveX86Relocation(Section, Offset,
@@ -723,7 +836,8 @@ void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
                           (uint32_t)(Value & 0xffffffffL), Type,
                           (uint32_t)(Addend & 0xffffffffL));
     break;
-  case Triple::ppc64:
+  case Triple::ppc64:   // Fall through.
+  case Triple::ppc64le:
     resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
     break;
   case Triple::systemz:
@@ -742,31 +856,37 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
   uint64_t RelType;
   Check(RelI.getType(RelType));
   int64_t Addend;
-  Check(RelI.getAdditionalInfo(Addend));
-  SymbolRef Symbol;
-  Check(RelI.getSymbol(Symbol));
+  Check(getELFRelocationAddend(RelI, Addend));
+  symbol_iterator Symbol = RelI.getSymbol();
 
   // Obtain the symbol name which is referenced in the relocation
   StringRef TargetName;
-  Symbol.getName(TargetName);
+  if (Symbol != Obj.end_symbols())
+    Symbol->getName(TargetName);
   DEBUG(dbgs() << "\t\tRelType: " << RelType
                << " Addend: " << Addend
                << " TargetName: " << TargetName
                << "\n");
   RelocationValueRef Value;
   // First search for the symbol in the local symbol table
-  SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
-  SymbolRef::Type SymType;
-  Symbol.getType(SymType);
+  SymbolTableMap::const_iterator lsi = Symbols.end();
+  SymbolRef::Type SymType = SymbolRef::ST_Unknown;
+  if (Symbol != Obj.end_symbols()) {
+    lsi = Symbols.find(TargetName.data());
+    Symbol->getType(SymType);
+  }
   if (lsi != Symbols.end()) {
     Value.SectionID = lsi->second.first;
+    Value.Offset = lsi->second.second;
     Value.Addend = lsi->second.second + Addend;
   } else {
     // Search for the symbol in the global symbol table
-    SymbolTableMap::const_iterator gsi =
-        GlobalSymbolTable.find(TargetName.data());
+    SymbolTableMap::const_iterator gsi = GlobalSymbolTable.end();
+    if (Symbol != Obj.end_symbols())
+      gsi = GlobalSymbolTable.find(TargetName.data());
     if (gsi != GlobalSymbolTable.end()) {
       Value.SectionID = gsi->second.first;
+      Value.Offset = gsi->second.second;
       Value.Addend = gsi->second.second + Addend;
     } else {
       switch (SymType) {
@@ -775,7 +895,7 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
           // 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());
-          Symbol.getSection(si);
+          Symbol->getSection(si);
           if (si == Obj.end_sections())
             llvm_unreachable("Symbol section not found, bad object file format!");
           DEBUG(dbgs() << "\t\tThis is section symbol\n");
@@ -789,9 +909,17 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
           Value.Addend = Addend;
           break;
         }
+        case SymbolRef::ST_Data:
         case SymbolRef::ST_Unknown: {
           Value.SymbolName = TargetName.data();
           Value.Addend = Addend;
+
+          // Absolute relocations will have a zero symbol ID (STN_UNDEF), which
+          // will manifest here as a NULL symbol name.
+          // We can set this as a valid (but empty) symbol name, and rely
+          // on addRelocationForSymbol to handle this.
+          if (!Value.SymbolName)
+              Value.SymbolName = "";
           break;
         }
         default:
@@ -876,7 +1004,7 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
       uint8_t *StubTargetAddr = createStubFunction(Section.Address +
                                                    Section.StubOffset);
       RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
-                         ELF::R_ARM_ABS32, Value.Addend);
+                         ELF::R_ARM_PRIVATE_0, Value.Addend);
       if (Value.SymbolName)
         addRelocationForSymbol(RE, Value.SymbolName);
       else
@@ -903,8 +1031,8 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
     //  Look up for existing stub.
     StubMap::const_iterator i = Stubs.find(Value);
     if (i != Stubs.end()) {
-      resolveRelocation(Section, Offset,
-                        (uint64_t)Section.Address + i->second, RelType, 0);
+      RelocationEntry RE(SectionID, Offset, RelType, i->second);
+      addRelocationForSection(RE, SectionID);
       DEBUG(dbgs() << " Stub function found\n");
     } else {
       // Create a new stub function.
@@ -916,10 +1044,10 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
       // Creating Hi and Lo relocations for the filled stub instructions.
       RelocationEntry REHi(SectionID,
                            StubTargetAddr - Section.Address,
-                           ELF::R_MIPS_HI16, Value.Addend);
+                           ELF::R_MIPS_UNUSED1, Value.Addend);
       RelocationEntry RELo(SectionID,
                            StubTargetAddr - Section.Address + 4,
-                           ELF::R_MIPS_LO16, Value.Addend);
+                           ELF::R_MIPS_UNUSED2, Value.Addend);
 
       if (Value.SymbolName) {
         addRelocationForSymbol(REHi, Value.SymbolName);
@@ -929,12 +1057,11 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
         addRelocationForSection(RELo, Value.SectionID);
       }
 
-      resolveRelocation(Section, Offset,
-                        (uint64_t)Section.Address + Section.StubOffset,
-                        RelType, 0);
+      RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset);
+      addRelocationForSection(RE, SectionID);
       Section.StubOffset += getMaxStubSize();
     }
-  } else if (Arch == Triple::ppc64) {
+  } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
     if (RelType == ELF::R_PPC64_REL24) {
       // A PPC branch relocation will need a stub function if the target is
       // an external symbol (Symbol::ST_Unknown) or if the target address
@@ -1017,7 +1144,10 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
       RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
       // Extra check to avoid relocation againt empty symbols (usually
       // the R_PPC64_TOC).
-      if (Value.SymbolName && !TargetName.empty())
+      if (SymType != SymbolRef::ST_Unknown && TargetName.empty())
+        Value.SymbolName = NULL;
+
+      if (Value.SymbolName)
         addRelocationForSymbol(RE, Value.SymbolName);
       else
         addRelocationForSection(RE, Value.SectionID);
@@ -1069,8 +1199,67 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
                         ELF::R_390_PC32DBL, Addend);
     else
       resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
+  } else if (Arch == Triple::x86_64 && RelType == ELF::R_X86_64_PLT32) {
+    // The way the PLT relocations normally work is that the linker allocates the
+    // PLT and this relocation makes a PC-relative call into the PLT.  The PLT
+    // entry will then jump to an address provided by the GOT.  On first call, the
+    // GOT address will point back into PLT code that resolves the symbol.  After
+    // the first call, the GOT entry points to the actual function.
+    //
+    // For local functions we're ignoring all of that here and just replacing
+    // the PLT32 relocation type with PC32, which will translate the relocation
+    // into a PC-relative call directly to the function. For external symbols we
+    // can't be sure the function will be within 2^32 bytes of the call site, so
+    // we need to create a stub, which calls into the GOT.  This case is
+    // equivalent to the usual PLT implementation except that we use the stub
+    // mechanism in RuntimeDyld (which puts stubs at the end of the section)
+    // rather than allocating a PLT section.
+    if (Value.SymbolName) {
+      // This is a call to an external function.
+      // Look for an existing stub.
+      SectionEntry &Section = Sections[SectionID];
+      StubMap::const_iterator i = Stubs.find(Value);
+      uintptr_t StubAddress;
+      if (i != Stubs.end()) {
+        StubAddress = uintptr_t(Section.Address) + i->second;
+        DEBUG(dbgs() << " Stub function found\n");
+      } else {
+        // Create a new stub function (equivalent to a PLT entry).
+        DEBUG(dbgs() << " Create a new stub function\n");
+
+        uintptr_t BaseAddress = uintptr_t(Section.Address);
+        uintptr_t StubAlignment = getStubAlignment();
+        StubAddress = (BaseAddress + Section.StubOffset +
+                      StubAlignment - 1) & -StubAlignment;
+        unsigned StubOffset = StubAddress - BaseAddress;
+        Stubs[Value] = StubOffset;
+        createStubFunction((uint8_t *)StubAddress);
+
+        // Create a GOT entry for the external function.
+        GOTEntries.push_back(Value);
+
+        // Make our stub function a relative call to the GOT entry.
+        RelocationEntry RE(SectionID, StubOffset + 2,
+                           ELF::R_X86_64_GOTPCREL, -4);
+        addRelocationForSymbol(RE, Value.SymbolName);
+
+        // Bump our stub offset counter
+        Section.StubOffset = StubOffset + getMaxStubSize();
+      }
+
+      // Make the target call a call into the stub table.
+      resolveRelocation(Section, Offset, StubAddress,
+                      ELF::R_X86_64_PC32, Addend);
+    } else {
+      RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
+                         Value.Offset);
+      addRelocationForSection(RE, Value.SectionID);
+    }
   } else {
-    RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
+    if (Arch == Triple::x86_64 && RelType == ELF::R_X86_64_GOTPCREL) {
+      GOTEntries.push_back(Value);
+    }
+    RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
     if (Value.SymbolName)
       addRelocationForSymbol(RE, Value.SymbolName);
     else
@@ -1078,6 +1267,137 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
   }
 }
 
+void RuntimeDyldELF::updateGOTEntries(StringRef Name, uint64_t Addr) {
+
+  SmallVectorImpl<std::pair<SID, GOTRelocations> >::iterator it;
+  SmallVectorImpl<std::pair<SID, GOTRelocations> >::iterator end = GOTs.end();
+
+  for (it = GOTs.begin(); it != end; ++it) {
+    GOTRelocations &GOTEntries = it->second;
+    for (int i = 0, e = GOTEntries.size(); i != e; ++i) {
+      if (GOTEntries[i].SymbolName != 0 && GOTEntries[i].SymbolName == Name) {
+        GOTEntries[i].Offset = Addr;
+      }
+    }
+  }
+}
+
+size_t RuntimeDyldELF::getGOTEntrySize() {
+  // We don't use the GOT in all of these cases, but it's essentially free
+  // to put them all here.
+  size_t Result = 0;
+  switch (Arch) {
+  case Triple::x86_64:
+  case Triple::aarch64:
+  case Triple::ppc64:
+  case Triple::ppc64le:
+  case Triple::systemz:
+    Result = sizeof(uint64_t);
+    break;
+  case Triple::x86:
+  case Triple::arm:
+  case Triple::thumb:
+  case Triple::mips:
+  case Triple::mipsel:
+    Result = sizeof(uint32_t);
+    break;
+  default: llvm_unreachable("Unsupported CPU type!");
+  }
+  return Result;
+}
+
+uint64_t RuntimeDyldELF::findGOTEntry(uint64_t LoadAddress,
+                                      uint64_t Offset) {
+
+  const size_t GOTEntrySize = getGOTEntrySize();
+
+  SmallVectorImpl<std::pair<SID, GOTRelocations> >::const_iterator it;
+  SmallVectorImpl<std::pair<SID, GOTRelocations> >::const_iterator end = GOTs.end();
+
+  int GOTIndex = -1;
+  for (it = GOTs.begin(); it != end; ++it) {
+    SID GOTSectionID = it->first;
+    const GOTRelocations &GOTEntries = it->second;
+
+    // Find the matching entry in our vector.
+    uint64_t SymbolOffset = 0;
+    for (int i = 0, e = GOTEntries.size(); i != e; ++i) {
+      if (GOTEntries[i].SymbolName == 0) {
+        if (getSectionLoadAddress(GOTEntries[i].SectionID) == LoadAddress &&
+            GOTEntries[i].Offset == Offset) {
+          GOTIndex = i;
+          SymbolOffset = GOTEntries[i].Offset;
+          break;
+        }
+      } else {
+        // GOT entries for external symbols use the addend as the address when
+        // the external symbol has been resolved.
+        if (GOTEntries[i].Offset == LoadAddress) {
+          GOTIndex = i;
+          // Don't use the Addend here.  The relocation handler will use it.
+          break;
+        }
+      }
+    }
+
+    if (GOTIndex != -1) {
+      if (GOTEntrySize == sizeof(uint64_t)) {
+        uint64_t *LocalGOTAddr = (uint64_t*)getSectionAddress(GOTSectionID);
+        // Fill in this entry with the address of the symbol being referenced.
+        LocalGOTAddr[GOTIndex] = LoadAddress + SymbolOffset;
+      } else {
+        uint32_t *LocalGOTAddr = (uint32_t*)getSectionAddress(GOTSectionID);
+        // Fill in this entry with the address of the symbol being referenced.
+        LocalGOTAddr[GOTIndex] = (uint32_t)(LoadAddress + SymbolOffset);
+      }
+
+      // Calculate the load address of this entry
+      return getSectionLoadAddress(GOTSectionID) + (GOTIndex * GOTEntrySize);
+    }
+  }
+
+  assert(GOTIndex != -1 && "Unable to find requested GOT entry.");
+  return 0;
+}
+
+void RuntimeDyldELF::finalizeLoad(ObjSectionToIDMap &SectionMap) {
+  // If necessary, allocate the global offset table
+  if (MemMgr) {
+    // Allocate the GOT if necessary
+    size_t numGOTEntries = GOTEntries.size();
+    if (numGOTEntries != 0) {
+      // Allocate memory for the section
+      unsigned SectionID = Sections.size();
+      size_t TotalSize = numGOTEntries * getGOTEntrySize();
+      uint8_t *Addr = MemMgr->allocateDataSection(TotalSize, getGOTEntrySize(),
+                                                  SectionID, ".got", false);
+      if (!Addr)
+        report_fatal_error("Unable to allocate memory for GOT!");
+
+      GOTs.push_back(std::make_pair(SectionID, GOTEntries));
+      Sections.push_back(SectionEntry(".got", Addr, TotalSize, 0));
+      // For now, initialize all GOT entries to zero.  We'll fill them in as
+      // needed when GOT-based relocations are applied.
+      memset(Addr, 0, TotalSize);
+    }
+  }
+  else {
+    report_fatal_error("Unable to allocate memory for GOT!");
+  }
+
+  // Look for and record the EH frame section.
+  ObjSectionToIDMap::iterator i, e;
+  for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
+    const SectionRef &Section = i->first;
+    StringRef Name;
+    Section.getName(Name);
+    if (Name == ".eh_frame") {
+      UnregisteredEHFrameSections.push_back(i->second);
+      break;
+    }
+  }
+}
+
 bool RuntimeDyldELF::isCompatibleFormat(const ObjectBuffer *Buffer) const {
   if (Buffer->getBufferSize() < strlen(ELF::ElfMagic))
     return false;