Completely rewrite ELFObjectWriter::RecordRelocation.

I started trying to fix a small issue, but this code has seen a small fix too
many.

The old code was fairly convoluted. Some of the issues it had:

* It failed to check if a symbol difference was in the some section when
  converting a relocation to pcrel.
* It failed to check if the relocation was already pcrel.
* The pcrel value computation was wrong in some cases (relocation-pc.s)
* It was missing quiet a few cases where it should not convert symbol
  relocations to section relocations, leaving the backends to patch it up.
* It would not propagate the fact that it had changed a relocation to pcrel,
  requiring a quiet nasty work around in ARM.
* It was missing comments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@205076 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCAsmBackend.h

@@ -97,7 +97,7 @@ public:
   /// data fragment, at the offset specified by the fixup and following the
   /// fixup kind as appropriate.
   virtual void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                          uint64_t Value) const = 0;
+                          uint64_t Value, bool IsPCRel) const = 0;
 
   /// @}
 

include/llvm/MC/MCAssembler.h

@@ -979,8 +979,8 @@ private:
   /// finishLayout - Finalize a layout, including fragment lowering.
   void finishLayout(MCAsmLayout &Layout);
 
-  uint64_t handleFixup(const MCAsmLayout &Layout,
+  std::pair<uint64_t, bool> handleFixup(const MCAsmLayout &Layout,
-                       MCFragment &F, const MCFixup &Fixup);
+                                        MCFragment &F, const MCFixup &Fixup);
 
 public:
   /// Compute the effective fragment size assuming it is laid out at the given

include/llvm/MC/MCELFObjectWriter.h

@@ -20,30 +20,10 @@ class MCAssembler;
 class MCFixup;
 class MCFragment;
 class MCObjectWriter;
+class MCSectionData;
 class MCSymbol;
 class MCValue;
 
-/// @name Relocation Data
-/// @{
-
-struct ELFRelocationEntry {
-  // Make these big enough for both 32-bit and 64-bit
-  uint64_t r_offset;
-  int Index;
-  unsigned Type;
-  const MCSymbol *Symbol;
-  uint64_t r_addend;
-  const MCFixup *Fixup;
-
-  ELFRelocationEntry()
-    : r_offset(0), Index(0), Type(0), Symbol(0), r_addend(0), Fixup(0) {}
-
-  ELFRelocationEntry(uint64_t RelocOffset, int Idx, unsigned RelType,
-                     const MCSymbol *Sym, uint64_t Addend, const MCFixup &Fixup)
-    : r_offset(RelocOffset), Index(Idx), Type(RelType), Symbol(Sym),
-      r_addend(Addend), Fixup(&Fixup) {}
-};
-
 class MCELFObjectTargetWriter {
   const uint8_t OSABI;
   const uint16_t EMachine;
@@ -73,17 +53,8 @@ public:
 
   virtual unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                                 bool IsPCRel) const = 0;
-  virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
-                                         const MCValue &Target,
-                                         const MCFragment &F,
-                                         const MCFixup &Fixup,
-                                         bool IsPCRel) const;
-  virtual const MCSymbol *undefinedExplicitRelSym(const MCValue &Target,
-                                                  const MCFixup &Fixup,
-                                                  bool IsPCRel) const;
 
-  virtual void sortRelocs(const MCAssembler &Asm,
+  virtual bool needsRelocateWithSymbol(unsigned Type) const;
-                          std::vector<ELFRelocationEntry> &Relocs);
 
   /// @name Accessors
   /// @{

include/llvm/MC/MCMachObjectWriter.h

@@ -230,7 +230,8 @@ public:
 
   void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
                         const MCFragment *Fragment, const MCFixup &Fixup,
-                        MCValue Target, uint64_t &FixedValue) override;
+                        MCValue Target, bool &IsPCRel,
+                        uint64_t &FixedValue) override;
 
   void BindIndirectSymbols(MCAssembler &Asm);
 

include/llvm/MC/MCObjectWriter.h

@@ -80,6 +80,7 @@ public:
                                 const MCAsmLayout &Layout,
                                 const MCFragment *Fragment,
                                 const MCFixup &Fixup, MCValue Target,
+                                bool &IsPCRel,
                                 uint64_t &FixedValue) = 0;
 
   /// \brief Check whether the difference (A - B) between two symbol

lib/MC/ELFObjectWriter.cpp

@@ -76,6 +76,27 @@ public:
                    uint8_t other, uint32_t shndx, bool Reserved);
 };
 
+struct ELFRelocationEntry {
+  uint64_t Offset; // Where is the relocation.
+  bool UseSymbol;  // Relocate with a symbol, not the section.
+  union {
+    const MCSymbol *Symbol;       // The symbol to relocate with.
+    const MCSectionData *Section; // The section to relocate with.
+  };
+  unsigned Type;   // The type of the relocation.
+  uint64_t Addend; // The addend to use.
+
+  ELFRelocationEntry(uint64_t Offset, const MCSymbol *Symbol, unsigned Type,
+                     uint64_t Addend)
+      : Offset(Offset), UseSymbol(true), Symbol(Symbol), Type(Type),
+        Addend(Addend) {}
+
+  ELFRelocationEntry(uint64_t Offset, const MCSectionData *Section,
+                     unsigned Type, uint64_t Addend)
+      : Offset(Offset), UseSymbol(false), Section(Section), Type(Type),
+        Addend(Addend) {}
+};
+
 class ELFObjectWriter : public MCObjectWriter {
   FragmentWriter FWriter;
 
@@ -125,8 +146,8 @@ class ELFObjectWriter : public MCObjectWriter {
     SmallPtrSet<const MCSymbol *, 16> WeakrefUsedInReloc;
     DenseMap<const MCSymbol *, const MCSymbol *> Renames;
 
-    llvm::DenseMap<const MCSectionData*,
+    llvm::DenseMap<const MCSectionData *, std::vector<ELFRelocationEntry>>
-                   std::vector<ELFRelocationEntry> > Relocations;
+    Relocations;
     DenseMap<const MCSection*, uint64_t> SectionStringTableIndex;
 
     /// @}
@@ -153,27 +174,7 @@ class ELFObjectWriter : public MCObjectWriter {
     unsigned ShstrtabIndex;
 
 
-    const MCSymbol *SymbolToReloc(const MCAssembler &Asm,
-                                  const MCValue &Target,
-                                  const MCFragment &F,
-                                  const MCFixup &Fixup,
-                                  bool IsPCRel) const;
-
     // TargetObjectWriter wrappers.
-    const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
-                                   const MCValue &Target,
-                                   const MCFragment &F,
-                                   const MCFixup &Fixup,
-                                   bool IsPCRel) const {
-      return TargetObjectWriter->ExplicitRelSym(Asm, Target, F, Fixup, IsPCRel);
-    }
-    const MCSymbol *undefinedExplicitRelSym(const MCValue &Target,
-                                            const MCFixup &Fixup,
-                                            bool IsPCRel) const {
-      return TargetObjectWriter->undefinedExplicitRelSym(Target, Fixup,
-                                                         IsPCRel);
-    }
-
     bool is64Bit() const { return TargetObjectWriter->is64Bit(); }
     bool hasRelocationAddend() const {
       return TargetObjectWriter->hasRelocationAddend();
@@ -213,9 +214,14 @@ class ELFObjectWriter : public MCObjectWriter {
                           const MCAsmLayout &Layout,
                           SectionIndexMapTy &SectionIndexMap);
 
+    bool shouldRelocateWithSymbol(const MCSymbolRefExpr *RefA,
+                                  const MCSymbolData *SD, uint64_t C,
+                                  unsigned Type) const;
+
     void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
                           const MCFragment *Fragment, const MCFixup &Fixup,
-                          MCValue Target, uint64_t &FixedValue) override;
+                          MCValue Target, bool &IsPCRel,
+                          uint64_t &FixedValue) override;
 
     uint64_t getSymbolIndexInSymbolTable(const MCAssembler &Asm,
                                          const MCSymbol *S);
@@ -716,146 +722,186 @@ void ELFObjectWriter::WriteSymbolTable(MCDataFragment *SymtabF,
   }
 }
 
-const MCSymbol *ELFObjectWriter::SymbolToReloc(const MCAssembler &Asm,
+// It is always valid to create a relocation with a symbol. It is preferable
-                                               const MCValue &Target,
+// to use a relocation with a section if that is possible. Using the section
-                                               const MCFragment &F,
+// allows us to omit some local symbols from the symbol table.
-                                               const MCFixup &Fixup,
+bool ELFObjectWriter::shouldRelocateWithSymbol(const MCSymbolRefExpr *RefA,
-                                               bool IsPCRel) const {
+                                               const MCSymbolData *SD,
-  const MCSymbol &Symbol = Target.getSymA()->getSymbol();
+                                               uint64_t C,
-  const MCSymbol &ASymbol = Symbol.AliasedSymbol();
+                                               unsigned Type) const {
-  const MCSymbol *Renamed = Renames.lookup(&Symbol);
+  // A PCRel relocation to an absolute value has no symbol (or section). We
-  const MCSymbolData &SD = Asm.getSymbolData(Symbol);
+  // represent that with a relocation to a null section.
+  if (!RefA)
+    return false;
 
-  if (ASymbol.isUndefined()) {
+  MCSymbolRefExpr::VariantKind Kind = RefA->getKind();
-    if (Renamed)
+  switch (Kind) {
-      return Renamed;
+  default:
-    return undefinedExplicitRelSym(Target, Fixup, IsPCRel);
+    break;
+  // The .odp creation emits a relocation against the symbol ".TOC." which
+  // create a R_PPC64_TOC relocation. However the relocation symbol name
+  // in final object creation should be NULL, since the symbol does not
+  // really exist, it is just the reference to TOC base for the current
+  // object file. Since the symbol is undefined, returning false results
+  // in a relocation with a null section which is the desired result.
+  case MCSymbolRefExpr::VK_PPC_TOCBASE:
+    return false;
+
+  // These VariantKind cause the relocation to refer to something other than
+  // the symbol itself, like a linker generated table. Since the address of
+  // symbol is not relevant, we cannot replace the symbol with the
+  // section and patch the difference in the addend.
+  case MCSymbolRefExpr::VK_GOT:
+  case MCSymbolRefExpr::VK_PLT:
+  case MCSymbolRefExpr::VK_GOTPCREL:
+  case MCSymbolRefExpr::VK_Mips_GOT:
+  case MCSymbolRefExpr::VK_PPC_GOT_LO:
+  case MCSymbolRefExpr::VK_PPC_GOT_HI:
+  case MCSymbolRefExpr::VK_PPC_GOT_HA:
+    return true;
   }
 
-  if (SD.isExternal()) {
+  // An undefined symbol is not in any section, so the relocation has to point
-    if (Renamed)
+  // to the symbol itself.
-      return Renamed;
+  const MCSymbol &Sym = SD->getSymbol();
-    return &Symbol;
+  if (Sym.isUndefined())
+    return true;
+
+  unsigned Binding = MCELF::GetBinding(*SD);
+  switch(Binding) {
+  default:
+    llvm_unreachable("Invalid Binding");
+  case ELF::STB_LOCAL:
+    break;
+  case ELF::STB_WEAK:
+    // If the symbol is weak, it might be overridden by a symbol in another
+    // file. The relocation has to point to the symbol so that the linker
+    // can update it.
+    return true;
+  case ELF::STB_GLOBAL:
+    // Global ELF symbols can be preempted by the dynamic linker. The relocation
+    // has to point to the symbol for a reason analogous to the STB_WEAK case.
+    return true;
   }
 
-  const MCSectionELF &Section =
+  // If a relocation points to a mergeable section, we have to be careful.
-    static_cast<const MCSectionELF&>(ASymbol.getSection());
+  // If the offset is zero, a relocation with the section will encode the
-  const SectionKind secKind = Section.getKind();
+  // same information. With a non-zero offset, the situation is different.
-
+  // For example, a relocation can point 42 bytes past the end of a string.
-  if (secKind.isBSS())
+  // If we change such a relocation to use the section, the linker would think
-    return ExplicitRelSym(Asm, Target, F, Fixup, IsPCRel);
+  // that it pointed to another string and subtracting 42 at runtime will
-
+  // produce the wrong value.
-  if (secKind.isThreadLocal()) {
+  auto &Sec = cast<MCSectionELF>(Sym.getSection());
-    if (Renamed)
+  unsigned Flags = Sec.getFlags();
-      return Renamed;
+  if (Flags & ELF::SHF_MERGE) {
-    return &Symbol;
+    if (C != 0)
+      return true;
   }
 
-  MCSymbolRefExpr::VariantKind Kind = Target.getSymA()->getKind();
+  // Most TLS relocations use a got, so they need the symbol. Even those that
-  const MCSectionELF &Sec2 =
+  // are just an offset (@tpoff), require a symbol in some linkers (gold,
-    static_cast<const MCSectionELF&>(F.getParent()->getSection());
+  // but not bfd ld).
-
+  if (Flags & ELF::SHF_TLS)
-  if (&Sec2 != &Section &&
+    return true;
-      (Kind == MCSymbolRefExpr::VK_PLT ||
-       Kind == MCSymbolRefExpr::VK_GOTPCREL ||
-       Kind == MCSymbolRefExpr::VK_GOTOFF)) {
-    if (Renamed)
-      return Renamed;
-    return &Symbol;
-  }
-
-  if (Section.getFlags() & ELF::SHF_MERGE) {
-    if (Target.getConstant() == 0)
-      return ExplicitRelSym(Asm, Target, F, Fixup, IsPCRel);
-    if (Renamed)
-      return Renamed;
-    return &Symbol;
-  }
-
-  return ExplicitRelSym(Asm, Target, F, Fixup, IsPCRel);
 
+  if (TargetObjectWriter->needsRelocateWithSymbol(Type))
+    return true;
+  return false;
 }
 
-
 void ELFObjectWriter::RecordRelocation(const MCAssembler &Asm,
                                        const MCAsmLayout &Layout,
                                        const MCFragment *Fragment,
                                        const MCFixup &Fixup,
                                        MCValue Target,
+                                       bool &IsPCRel,
                                        uint64_t &FixedValue) {
-  int64_t Addend = 0;
+  const MCSectionData *FixupSection = Fragment->getParent();
-  int Index = 0;
+  uint64_t C = Target.getConstant();
-  int64_t Value = Target.getConstant();
+  uint64_t FixupOffset = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
-  const MCSymbol *RelocSymbol = NULL;
 
-  bool IsPCRel = isFixupKindPCRel(Asm, Fixup.getKind());
+  if (const MCSymbolRefExpr *RefB = Target.getSymB()) {
-  if (!Target.isAbsolute()) {
+    assert(RefB->getKind() == MCSymbolRefExpr::VK_None &&
-    const MCSymbol &Symbol = Target.getSymA()->getSymbol();
+           "Should not have constructed this");
-    const MCSymbol &ASymbol = Symbol.AliasedSymbol();
-    RelocSymbol = SymbolToReloc(Asm, Target, *Fragment, Fixup, IsPCRel);
 
-    if (const MCSymbolRefExpr *RefB = Target.getSymB()) {
+    // Let A, B and C being the components of Target and R be the location of
-      const MCSymbol &SymbolB = RefB->getSymbol();
+    // the fixup. If the fixup is not pcrel, we want to compute (A - B + C).
-      MCSymbolData &SDB = Asm.getSymbolData(SymbolB);
+    // If it is pcrel, we want to compute (A - B + C - R).
-      IsPCRel = true;
 
-      if (!SDB.getFragment())
+    // In general, ELF has no relocations for -B. It can only represent (A + C)
-        Asm.getContext().FatalError(
+    // or (A + C - R). If B = R + K and the relocation is not pcrel, we can
-            Fixup.getLoc(),
+    // replace B to implement it: (A - R - K + C)
-            Twine("symbol '") + SymbolB.getName() +
+    if (IsPCRel)
-                "' can not be undefined in a subtraction expression");
+      Asm.getContext().FatalError(
+          Fixup.getLoc(),
+          "No relocation available to represent this relative expression");
 
-      // Offset of the symbol in the section
+    const MCSymbol &SymB = RefB->getSymbol();
-      int64_t a = Layout.getSymbolOffset(&SDB);
 
-      // Offset of the relocation in the section
+    if (SymB.isUndefined())
-      int64_t b = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
+      Asm.getContext().FatalError(
-      Value += b - a;
+          Fixup.getLoc(),
-    }
+          Twine("symbol '") + SymB.getName() +
+              "' can not be undefined in a subtraction expression");
 
-    if (!RelocSymbol) {
+    assert(!SymB.isAbsolute() && "Should have been folded");
-      MCSymbolData &SD = Asm.getSymbolData(ASymbol);
+    const MCSection &SecB = SymB.getSection();
-      MCFragment *F = SD.getFragment();
+    if (&SecB != &FixupSection->getSection())
+      Asm.getContext().FatalError(
+          Fixup.getLoc(), "Cannot represent a difference across sections");
 
-      if (F) {
+    const MCSymbolData &SymBD = Asm.getSymbolData(SymB);
-        Index = F->getParent()->getOrdinal() + 1;
+    uint64_t SymBOffset = Layout.getSymbolOffset(&SymBD);
-        // Offset of the symbol in the section
+    uint64_t K = SymBOffset - FixupOffset;
-        Value += Layout.getSymbolOffset(&SD);
+    IsPCRel = true;
-      } else {
+    C -= K;
-        Index = 0;
-      }
-    } else {
-      if (Target.getSymA()->getKind() == MCSymbolRefExpr::VK_WEAKREF)
-        WeakrefUsedInReloc.insert(RelocSymbol);
-      else
-        UsedInReloc.insert(RelocSymbol);
-      Index = -1;
-    }
-    Addend = Value;
-    if (hasRelocationAddend())
-      Value = 0;
   }
 
-  FixedValue = Value;
+  // We either rejected the fixup or folded B into C at this point.
+  const MCSymbolRefExpr *RefA = Target.getSymA();
+  const MCSymbol *SymA = RefA ? &RefA->getSymbol() : nullptr;
+  const MCSymbolData *SymAD = SymA ? &Asm.getSymbolData(*SymA) : nullptr;
+
   unsigned Type = GetRelocType(Target, Fixup, IsPCRel);
-  MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ?
+  bool RelocateWithSymbol = shouldRelocateWithSymbol(RefA, SymAD, C, Type);
-    MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
+  if (!RelocateWithSymbol && SymA && !SymA->isUndefined())
+    C += Layout.getSymbolOffset(SymAD);
+
+  uint64_t Addend = 0;
+  if (hasRelocationAddend()) {
+    Addend = C;
+    C = 0;
+  }
+
+  FixedValue = C;
+
+  // FIXME: What is this!?!?
+  MCSymbolRefExpr::VariantKind Modifier =
+      RefA ? RefA->getKind() : MCSymbolRefExpr::VK_None;
   if (RelocNeedsGOT(Modifier))
     NeedsGOT = true;
 
-  uint64_t RelocOffset = Layout.getFragmentOffset(Fragment) +
+  if (!RelocateWithSymbol) {
-    Fixup.getOffset();
+    const MCSection *SecA =
+        (SymA && !SymA->isUndefined()) ? &SymA->getSection() : nullptr;
+    const MCSectionData *SecAD = SecA ? &Asm.getSectionData(*SecA) : nullptr;
+    ELFRelocationEntry Rec(FixupOffset, SecAD, Type, Addend);
+    Relocations[FixupSection].push_back(Rec);
+    return;
+  }
 
-  if (!hasRelocationAddend())
+  if (SymA) {
-    Addend = 0;
+    if (const MCSymbol *R = Renames.lookup(SymA))
+      SymA = R;
 
-  if (is64Bit())
+    if (RefA->getKind() == MCSymbolRefExpr::VK_WEAKREF)
-    assert(isInt<64>(Addend));
+      WeakrefUsedInReloc.insert(SymA);
-  else
+    else
-    assert(isInt<32>(Addend));
+      UsedInReloc.insert(SymA);
-
+  }
-  ELFRelocationEntry ERE(RelocOffset, Index, Type, RelocSymbol, Addend, Fixup);
+  ELFRelocationEntry Rec(FixupOffset, SymA, Type, Addend);
-  Relocations[Fragment->getParent()].push_back(ERE);
+  Relocations[FixupSection].push_back(Rec);
+  return;
 }
 
 
@@ -1154,51 +1200,71 @@ void ELFObjectWriter::WriteSecHdrEntry(uint32_t Name, uint32_t Type,
   WriteWord(EntrySize); // sh_entsize
 }
 
+// ELF doesn't require relocations to be in any order. We sort by the r_offset,
+// just to match gnu as for easier comparison. The use type is an arbitrary way
+// of making the sort deterministic.
+static int cmpRel(const ELFRelocationEntry *AP, const ELFRelocationEntry *BP) {
+  const ELFRelocationEntry &A = *AP;
+  const ELFRelocationEntry &B = *BP;
+  if (A.Offset != B.Offset)
+    return B.Offset - A.Offset;
+  if (B.Type != A.Type)
+    return A.Type - B.Type;
+  llvm_unreachable("ELFRelocs might be unstable!");
+}
+
+static void sortRelocs(const MCAssembler &Asm,
+                       std::vector<ELFRelocationEntry> &Relocs) {
+  array_pod_sort(Relocs.begin(), Relocs.end(), cmpRel);
+}
+
 void ELFObjectWriter::WriteRelocationsFragment(const MCAssembler &Asm,
                                                MCDataFragment *F,
                                                const MCSectionData *SD) {
   std::vector<ELFRelocationEntry> &Relocs = Relocations[SD];
 
-  // Sort the relocation entries. Most targets just sort by r_offset, but some
+  sortRelocs(Asm, Relocs);
-  // (e.g., MIPS) have additional constraints.
-  TargetObjectWriter->sortRelocs(Asm, Relocs);
 
   for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
-    ELFRelocationEntry entry = Relocs[e - i - 1];
+    const ELFRelocationEntry &Entry = Relocs[e - i - 1];
+
+    unsigned Index;
+    if (Entry.UseSymbol) {
+      Index = getSymbolIndexInSymbolTable(Asm, Entry.Symbol);
+    } else {
+      const MCSectionData *Sec = Entry.Section;
+      if (Sec)
+        Index = Sec->getOrdinal() + FileSymbolData.size() +
+                LocalSymbolData.size() + 1;
+      else
+        Index = 0;
+    }
 
-    if (!entry.Index)
-      ;
-    // FIXME: this is most likely a bug if index overflows.
-    else if (entry.Index < 0)
-      entry.Index = getSymbolIndexInSymbolTable(Asm, entry.Symbol);
-    else
-      entry.Index += FileSymbolData.size() + LocalSymbolData.size();
     if (is64Bit()) {
-      write(*F, entry.r_offset);
+      write(*F, Entry.Offset);
       if (TargetObjectWriter->isN64()) {
-        write(*F, uint32_t(entry.Index));
+        write(*F, uint32_t(Index));
 
-        write(*F, TargetObjectWriter->getRSsym(entry.Type));
+        write(*F, TargetObjectWriter->getRSsym(Entry.Type));
-        write(*F, TargetObjectWriter->getRType3(entry.Type));
+        write(*F, TargetObjectWriter->getRType3(Entry.Type));
-        write(*F, TargetObjectWriter->getRType2(entry.Type));
+        write(*F, TargetObjectWriter->getRType2(Entry.Type));
-        write(*F, TargetObjectWriter->getRType(entry.Type));
+        write(*F, TargetObjectWriter->getRType(Entry.Type));
-      }
+      } else {
-      else {
         struct ELF::Elf64_Rela ERE64;
-        ERE64.setSymbolAndType(entry.Index, entry.Type);
+        ERE64.setSymbolAndType(Index, Entry.Type);
         write(*F, ERE64.r_info);
       }
       if (hasRelocationAddend())
-        write(*F, entry.r_addend);
+        write(*F, Entry.Addend);
     } else {
-      write(*F, uint32_t(entry.r_offset));
+      write(*F, uint32_t(Entry.Offset));
 
       struct ELF::Elf32_Rela ERE32;
-      ERE32.setSymbolAndType(entry.Index, entry.Type);
+      ERE32.setSymbolAndType(Index, Entry.Type);
       write(*F, ERE32.r_info);
 
       if (hasRelocationAddend())
-        write(*F, uint32_t(entry.r_addend));
+        write(*F, uint32_t(Entry.Addend));
     }
   }
 }

lib/MC/MCAssembler.cpp

@@ -779,20 +779,22 @@ void MCAssembler::writeSectionData(const MCSectionData *SD,
          Layout.getSectionAddressSize(SD));
 }
 
-
+std::pair<uint64_t, bool> MCAssembler::handleFixup(const MCAsmLayout &Layout,
-uint64_t MCAssembler::handleFixup(const MCAsmLayout &Layout,
+                                                   MCFragment &F,
-                                  MCFragment &F,
+                                                   const MCFixup &Fixup) {
-                                  const MCFixup &Fixup) {
   // Evaluate the fixup.
   MCValue Target;
   uint64_t FixedValue;
+  bool IsPCRel = Backend.getFixupKindInfo(Fixup.getKind()).Flags &
+                 MCFixupKindInfo::FKF_IsPCRel;
   if (!evaluateFixup(Layout, Fixup, &F, Target, FixedValue)) {
     // The fixup was unresolved, we need a relocation. Inform the object
     // writer of the relocation, and give it an opportunity to adjust the
     // fixup value if need be.
-    getWriter().RecordRelocation(*this, Layout, &F, Fixup, Target, FixedValue);
+    getWriter().RecordRelocation(*this, Layout, &F, Fixup, Target, IsPCRel,
+                                 FixedValue);
   }
-  return FixedValue;
+  return std::make_pair(FixedValue, IsPCRel);
 }
 
 void MCAssembler::Finish() {
@@ -856,9 +858,11 @@ void MCAssembler::Finish() {
         for (MCEncodedFragmentWithFixups::fixup_iterator it3 = F->fixup_begin(),
              ie3 = F->fixup_end(); it3 != ie3; ++it3) {
           MCFixup &Fixup = *it3;
-          uint64_t FixedValue = handleFixup(Layout, *F, Fixup);
+          uint64_t FixedValue;
+          bool IsPCRel;
+          std::tie(FixedValue, IsPCRel) = handleFixup(Layout, *F, Fixup);
           getBackend().applyFixup(Fixup, F->getContents().data(),
-                                  F->getContents().size(), FixedValue);
+                                  F->getContents().size(), FixedValue, IsPCRel);
         }
       }
     }

lib/MC/MCELFObjectTargetWriter.cpp

@@ -24,38 +24,6 @@ MCELFObjectTargetWriter::MCELFObjectTargetWriter(bool Is64Bit_,
     IsN64(IsN64_){
 }
 
-const MCSymbol *MCELFObjectTargetWriter::ExplicitRelSym(const MCAssembler &Asm,
+bool MCELFObjectTargetWriter::needsRelocateWithSymbol(unsigned Type) const {
-                                                        const MCValue &Target,
+  return false;
-                                                        const MCFragment &F,
-                                                        const MCFixup &Fixup,
-                                                        bool IsPCRel) const {
-  return NULL;
-}
-
-const MCSymbol *MCELFObjectTargetWriter::undefinedExplicitRelSym(const MCValue &Target,
-                                                                 const MCFixup &Fixup,
-                                                                 bool IsPCRel) const {
-  const MCSymbol &Symbol = Target.getSymA()->getSymbol();
-  return &Symbol.AliasedSymbol();
-}
-
-// ELF doesn't require relocations to be in any order. We sort by the r_offset,
-// just to match gnu as for easier comparison. The use type and index is an
-// arbitrary way of making the sort deterministic.
-static int cmpRel(const ELFRelocationEntry *AP, const ELFRelocationEntry *BP) {
-  const ELFRelocationEntry &A = *AP;
-  const ELFRelocationEntry &B = *BP;
-  if (A.r_offset != B.r_offset)
-    return B.r_offset - A.r_offset;
-  if (B.Type != A.Type)
-    return A.Type - B.Type;
-  if (B.Index != A.Index)
-    return B.Index - A.Index;
-  llvm_unreachable("ELFRelocs might be unstable!");
-}
-
-void
-MCELFObjectTargetWriter::sortRelocs(const MCAssembler &Asm,
-                                    std::vector<ELFRelocationEntry> &Relocs) {
-  array_pod_sort(Relocs.begin(), Relocs.end(), cmpRel);
 }

lib/MC/MachObjectWriter.cpp

@@ -417,6 +417,7 @@ void MachObjectWriter::RecordRelocation(const MCAssembler &Asm,
                                         const MCFragment *Fragment,
                                         const MCFixup &Fixup,
                                         MCValue Target,
+                                        bool &IsPCRel,
                                         uint64_t &FixedValue) {
   TargetObjectWriter->RecordRelocation(this, Asm, Layout, Fragment, Fixup,
                                        Target, FixedValue);

lib/MC/WinCOFFObjectWriter.cpp

@@ -172,7 +172,8 @@ public:
 
   void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
                         const MCFragment *Fragment, const MCFixup &Fixup,
-                        MCValue Target, uint64_t &FixedValue) override;
+                        MCValue Target, bool &IsPCRel,
+                        uint64_t &FixedValue) override;
 
   void WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) override;
 };
@@ -656,6 +657,7 @@ void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
                                            const MCFragment *Fragment,
                                            const MCFixup &Fixup,
                                            MCValue Target,
+                                           bool &IsPCRel,
                                            uint64_t &FixedValue) {
   assert(Target.getSymA() != NULL && "Relocation must reference a symbol!");
 

lib/Target/AArch64/MCTargetDesc/AArch64AsmBackend.cpp

@@ -177,7 +177,7 @@ public:
   }
 
   void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                  uint64_t Value) const {
+                  uint64_t Value, bool IsPCRel) const {
     unsigned NumBytes = getFixupKindInfo(Fixup.getKind()).TargetSize / 8;
     Value = adjustFixupValue(Fixup.getKind(), Value);
     if (!Value) return;           // Doesn't change encoding.

lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp

@@ -97,10 +97,6 @@ public:
 { "fixup_arm_movw_lo16",     0,            20,  0 },
 { "fixup_t2_movt_hi16",      0,            20,  0 },
 { "fixup_t2_movw_lo16",      0,            20,  0 },
-{ "fixup_arm_movt_hi16_pcrel", 0,          20,  MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_arm_movw_lo16_pcrel", 0,          20,  MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_t2_movt_hi16_pcrel", 0,           20,  MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_t2_movw_lo16_pcrel", 0,           20,  MCFixupKindInfo::FKF_IsPCRel },
     };
     const static MCFixupKindInfo InfosBE[ARM::NumTargetFixupKinds] = {
 // This table *must* be in the order that the fixup_* kinds are defined in
@@ -138,10 +134,6 @@ public:
 { "fixup_arm_movw_lo16",     12,           20,  0 },
 { "fixup_t2_movt_hi16",      12,           20,  0 },
 { "fixup_t2_movw_lo16",      12,           20,  0 },
-{ "fixup_arm_movt_hi16_pcrel", 12,         20,  MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_arm_movw_lo16_pcrel", 12,         20,  MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_t2_movt_hi16_pcrel", 12,          20,  MCFixupKindInfo::FKF_IsPCRel },
-{ "fixup_t2_movw_lo16_pcrel", 12,          20,  MCFixupKindInfo::FKF_IsPCRel },
     };
 
     if (Kind < FirstTargetFixupKind)
@@ -161,7 +153,7 @@ public:
 
 
   void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                  uint64_t Value) const override;
+                  uint64_t Value, bool IsPCRel) const override;
 
   bool mayNeedRelaxation(const MCInst &Inst) const override;
 
@@ -315,7 +307,7 @@ bool ARMAsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const {
 }
 
 static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
-                                 MCContext *Ctx = NULL) {
+                                 bool IsPCRel, MCContext *Ctx) {
   unsigned Kind = Fixup.getKind();
   switch (Kind) {
   default:
@@ -325,11 +317,10 @@ static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
   case FK_Data_4:
     return Value;
   case ARM::fixup_arm_movt_hi16:
-    Value >>= 16;
+    if (!IsPCRel)
+      Value >>= 16;
     // Fallthrough
-  case ARM::fixup_arm_movw_lo16:
+  case ARM::fixup_arm_movw_lo16: {
-  case ARM::fixup_arm_movt_hi16_pcrel:
-  case ARM::fixup_arm_movw_lo16_pcrel: {
     unsigned Hi4 = (Value & 0xF000) >> 12;
     unsigned Lo12 = Value & 0x0FFF;
     // inst{19-16} = Hi4;
@@ -338,12 +329,10 @@ static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
     return Value;
   }
   case ARM::fixup_t2_movt_hi16:
-    Value >>= 16;
+    if (!IsPCRel)
+      Value >>= 16;
     // Fallthrough
-  case ARM::fixup_t2_movw_lo16:
+  case ARM::fixup_t2_movw_lo16: {
-  case ARM::fixup_t2_movt_hi16_pcrel:  //FIXME: Shouldn't this be shifted like
-                                       // the other hi16 fixup?
-  case ARM::fixup_t2_movw_lo16_pcrel: {
     unsigned Hi4 = (Value & 0xF000) >> 12;
     unsigned i = (Value & 0x800) >> 11;
     unsigned Mid3 = (Value & 0x700) >> 8;
@@ -629,7 +618,7 @@ void ARMAsmBackend::processFixupValue(const MCAssembler &Asm,
   // Try to get the encoded value for the fixup as-if we're mapping it into
   // the instruction. This allows adjustFixupValue() to issue a diagnostic
   // if the value aren't invalid.
-  (void)adjustFixupValue(Fixup, Value, &Asm.getContext());
+  (void)adjustFixupValue(Fixup, Value, false, &Asm.getContext());
 }
 
 /// getFixupKindNumBytes - The number of bytes the fixup may change.
@@ -670,12 +659,8 @@ static unsigned getFixupKindNumBytes(unsigned Kind) {
   case ARM::fixup_arm_thumb_blx:
   case ARM::fixup_arm_movt_hi16:
   case ARM::fixup_arm_movw_lo16:
-  case ARM::fixup_arm_movt_hi16_pcrel:
-  case ARM::fixup_arm_movw_lo16_pcrel:
   case ARM::fixup_t2_movt_hi16:
   case ARM::fixup_t2_movw_lo16:
-  case ARM::fixup_t2_movt_hi16_pcrel:
-  case ARM::fixup_t2_movw_lo16_pcrel:
     return 4;
   }
 }
@@ -720,21 +705,18 @@ static unsigned getFixupKindContainerSizeBytes(unsigned Kind) {
   case ARM::fixup_arm_thumb_blx:
   case ARM::fixup_arm_movt_hi16:
   case ARM::fixup_arm_movw_lo16:
-  case ARM::fixup_arm_movt_hi16_pcrel:
-  case ARM::fixup_arm_movw_lo16_pcrel:
   case ARM::fixup_t2_movt_hi16:
   case ARM::fixup_t2_movw_lo16:
-  case ARM::fixup_t2_movt_hi16_pcrel:
-  case ARM::fixup_t2_movw_lo16_pcrel:
     // Instruction size is 4 bytes.
     return 4;
   }
 }
 
 void ARMAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
-                               unsigned DataSize, uint64_t Value) const {
+                               unsigned DataSize, uint64_t Value,
+                               bool IsPCRel) const {
   unsigned NumBytes = getFixupKindNumBytes(Fixup.getKind());
-  Value = adjustFixupValue(Fixup, Value);
+  Value = adjustFixupValue(Fixup, Value, IsPCRel, nullptr);
   if (!Value) return;           // Doesn't change encoding.
 
   unsigned Offset = Fixup.getOffset();

lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp

@@ -36,10 +36,8 @@ namespace {
 
     unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                           bool IsPCRel) const override;
-    const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
+
-                                   const MCValue &Target, const MCFragment &F,
+    bool needsRelocateWithSymbol(unsigned Type) const override;
-                                   const MCFixup &Fixup,
-                                   bool IsPCRel) const override;
   };
 }
 
@@ -50,90 +48,18 @@ ARMELFObjectWriter::ARMELFObjectWriter(uint8_t OSABI)
 
 ARMELFObjectWriter::~ARMELFObjectWriter() {}
 
-// In ARM, _MergedGlobals and other most symbols get emitted directly.
+bool ARMELFObjectWriter::needsRelocateWithSymbol(unsigned Type) const {
-// I.e. not as an offset to a section symbol.
+  // FIXME: This is extremelly conservative. This really needs to use a
-// This code is an approximation of what ARM/gcc does.
+  // whitelist with a clear explanation for why each realocation needs to
+  // point to the symbol, not to the section.
+  switch (Type) {
+  default:
+    return true;
 
-STATISTIC(PCRelCount, "Total number of PIC Relocations");
+  case ELF::R_ARM_PREL31:
-STATISTIC(NonPCRelCount, "Total number of non-PIC relocations");
+  case ELF::R_ARM_ABS32:
-
+    return false;
-const MCSymbol *ARMELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
-                                                   const MCValue &Target,
-                                                   const MCFragment &F,
-                                                   const MCFixup &Fixup,
-                                                   bool IsPCRel) const {
-  const MCSymbol &Symbol = Target.getSymA()->getSymbol().AliasedSymbol();
-  bool EmitThisSym = false;
-
-  const MCSectionELF &Section =
-    static_cast<const MCSectionELF&>(Symbol.getSection());
-  bool InNormalSection = true;
-  unsigned RelocType = 0;
-  RelocType = GetRelocTypeInner(Target, Fixup, IsPCRel);
-  assert(!Target.getSymB() ||
-         Target.getSymB()->getKind() == MCSymbolRefExpr::VK_None);
-
-  DEBUG(
-      MCSymbolRefExpr::VariantKind Kind = Fixup.getAccessVariant();
-      dbgs() << "considering symbol "
-        << Section.getSectionName() << "/"
-        << Symbol.getName() << "/"
-        << " Rel:" << (unsigned)RelocType
-        << " Kind: " << (int)Kind
-        << " Tmp:"
-        << Symbol.isAbsolute() << "/" << Symbol.isDefined() << "/"
-        << Symbol.isVariable() << "/" << Symbol.isTemporary()
-        << " Counts:" << PCRelCount << "/" << NonPCRelCount << "\n");
-
-  if (IsPCRel) { ++PCRelCount;
-    switch (RelocType) {
-    default:
-      // Most relocation types are emitted as explicit symbols
-      InNormalSection =
-        StringSwitch<bool>(Section.getSectionName())
-        .Case(".data.rel.ro.local", false)
-        .Case(".data.rel", false)
-        .Case(".bss", false)
-        .Default(true);
-      EmitThisSym = true;
-      break;
-    case ELF::R_ARM_ABS32:
-      // But things get strange with R_ARM_ABS32
-      // In this case, most things that go in .rodata show up
-      // as section relative relocations
-      InNormalSection =
-        StringSwitch<bool>(Section.getSectionName())
-        .Case(".data.rel.ro.local", false)
-        .Case(".data.rel", false)
-        .Case(".rodata", false)
-        .Case(".bss", false)
-        .Default(true);
-      EmitThisSym = false;
-      break;
-    }
-  } else {
-    NonPCRelCount++;
-    InNormalSection =
-      StringSwitch<bool>(Section.getSectionName())
-      .Case(".data.rel.ro.local", false)
-      .Case(".rodata", false)
-      .Case(".data.rel", false)
-      .Case(".bss", false)
-      .Default(true);
-
-    switch (RelocType) {
-    default: EmitThisSym = true; break;
-    case ELF::R_ARM_ABS32: EmitThisSym = false; break;
-    case ELF::R_ARM_PREL31: EmitThisSym = false; break;
-    }
   }
-
-  if (EmitThisSym)
-    return &Symbol;
-  if (! Symbol.isTemporary() && InNormalSection) {
-    return &Symbol;
-  }
-  return NULL;
 }
 
 // Need to examine the Fixup when determining whether to 
@@ -191,19 +117,15 @@ unsigned ARMELFObjectWriter::GetRelocTypeInner(const MCValue &Target,
       Type = ELF::R_ARM_THM_JUMP24;
       break;
     case ARM::fixup_arm_movt_hi16:
-    case ARM::fixup_arm_movt_hi16_pcrel:
       Type = ELF::R_ARM_MOVT_PREL;
       break;
     case ARM::fixup_arm_movw_lo16:
-    case ARM::fixup_arm_movw_lo16_pcrel:
       Type = ELF::R_ARM_MOVW_PREL_NC;
       break;
     case ARM::fixup_t2_movt_hi16:
-    case ARM::fixup_t2_movt_hi16_pcrel:
       Type = ELF::R_ARM_THM_MOVT_PREL;
       break;
     case ARM::fixup_t2_movw_lo16:
-    case ARM::fixup_t2_movw_lo16_pcrel:
       Type = ELF::R_ARM_THM_MOVW_PREL_NC;
       break;
     case ARM::fixup_arm_thumb_bl:

lib/Target/ARM/MCTargetDesc/ARMFixupKinds.h

@@ -100,15 +100,6 @@ enum Fixups {
   fixup_t2_movt_hi16, // :upper16:
   fixup_t2_movw_lo16, // :lower16:
 
-  // It is possible to create an "immediate" that happens to be pcrel.
-  // movw r0, :lower16:Foo-(Bar+8) and movt  r0, :upper16:Foo-(Bar+8)
-  // result in different reloc tags than the above two.
-  // Needed to support ELF::R_ARM_MOVT_PREL and ELF::R_ARM_MOVW_PREL_NC
-  fixup_arm_movt_hi16_pcrel, // :upper16:
-  fixup_arm_movw_lo16_pcrel, // :lower16:
-  fixup_t2_movt_hi16_pcrel, // :upper16:
-  fixup_t2_movw_lo16_pcrel, // :lower16:
-
   // Marker
   LastTargetFixupKind,
   NumTargetFixupKinds = LastTargetFixupKind - FirstTargetFixupKind

lib/Target/ARM/MCTargetDesc/ARMMCCodeEmitter.cpp

@@ -975,19 +975,6 @@ getT2AddrModeImm0_1020s4OpValue(const MCInst &MI, unsigned OpIdx,
   return (Reg << 8) | Imm8;
 }
 
-// FIXME: This routine assumes that a binary
-// expression will always result in a PCRel expression
-// In reality, its only true if one or more subexpressions
-// is itself a PCRel (i.e. "." in asm or some other pcrel construct)
-// but this is good enough for now.
-static bool EvaluateAsPCRel(const MCExpr *Expr) {
-  switch (Expr->getKind()) {
-  default: llvm_unreachable("Unexpected expression type");
-  case MCExpr::SymbolRef: return false;
-  case MCExpr::Binary: return true;
-  }
-}
-
 uint32_t
 ARMMCCodeEmitter::getHiLo16ImmOpValue(const MCInst &MI, unsigned OpIdx,
                                       SmallVectorImpl<MCFixup> &Fixups,
@@ -1023,24 +1010,12 @@ ARMMCCodeEmitter::getHiLo16ImmOpValue(const MCInst &MI, unsigned OpIdx,
     switch (ARM16Expr->getKind()) {
     default: llvm_unreachable("Unsupported ARMFixup");
     case ARMMCExpr::VK_ARM_HI16:
-      if (!isTargetMachO(STI) && EvaluateAsPCRel(E))
+      Kind = MCFixupKind(isThumb2(STI) ? ARM::fixup_t2_movt_hi16
-        Kind = MCFixupKind(isThumb2(STI)
+                                       : ARM::fixup_arm_movt_hi16);
-                           ? ARM::fixup_t2_movt_hi16_pcrel
-                           : ARM::fixup_arm_movt_hi16_pcrel);
-      else
-        Kind = MCFixupKind(isThumb2(STI)
-                           ? ARM::fixup_t2_movt_hi16
-                           : ARM::fixup_arm_movt_hi16);
       break;
     case ARMMCExpr::VK_ARM_LO16:
-      if (!isTargetMachO(STI) && EvaluateAsPCRel(E))
+      Kind = MCFixupKind(isThumb2(STI) ? ARM::fixup_t2_movw_lo16
-        Kind = MCFixupKind(isThumb2(STI)
+                                       : ARM::fixup_arm_movw_lo16);
-                           ? ARM::fixup_t2_movw_lo16_pcrel
-                           : ARM::fixup_arm_movw_lo16_pcrel);
-      else
-        Kind = MCFixupKind(isThumb2(STI)
-                           ? ARM::fixup_t2_movw_lo16
-                           : ARM::fixup_arm_movw_lo16);
       break;
     }
     Fixups.push_back(MCFixup::Create(0, E, Kind, MI.getLoc()));
@@ -1050,14 +1025,8 @@ ARMMCCodeEmitter::getHiLo16ImmOpValue(const MCInst &MI, unsigned OpIdx,
   // it's just a plain immediate expression, and those evaluate to
   // the lower 16 bits of the expression regardless of whether
   // we have a movt or a movw.
-  if (!isTargetMachO(STI) && EvaluateAsPCRel(E))
+  Kind = MCFixupKind(isThumb2(STI) ? ARM::fixup_t2_movw_lo16
-    Kind = MCFixupKind(isThumb2(STI)
+                                   : ARM::fixup_arm_movw_lo16);
-                       ? ARM::fixup_t2_movw_lo16_pcrel
-                       : ARM::fixup_arm_movw_lo16_pcrel);
-  else
-    Kind = MCFixupKind(isThumb2(STI)
-                       ? ARM::fixup_t2_movw_lo16
-                       : ARM::fixup_arm_movw_lo16);
   Fixups.push_back(MCFixup::Create(0, E, Kind, MI.getLoc()));
   return 0;
 }

lib/Target/ARM/MCTargetDesc/ARMMachObjectWriter.cpp

@@ -123,23 +123,19 @@ static bool getARMFixupKindMachOInfo(unsigned Kind, unsigned &RelocType,
   //      0 - arm instructions
   //      1 - thumb instructions
   case ARM::fixup_arm_movt_hi16:
-  case ARM::fixup_arm_movt_hi16_pcrel:
     RelocType = unsigned(MachO::ARM_RELOC_HALF);
     Log2Size = 1;
     return true;
   case ARM::fixup_t2_movt_hi16:
-  case ARM::fixup_t2_movt_hi16_pcrel:
     RelocType = unsigned(MachO::ARM_RELOC_HALF);
     Log2Size = 3;
     return true;
 
   case ARM::fixup_arm_movw_lo16:
-  case ARM::fixup_arm_movw_lo16_pcrel:
     RelocType = unsigned(MachO::ARM_RELOC_HALF);
     Log2Size = 0;
     return true;
   case ARM::fixup_t2_movw_lo16:
-  case ARM::fixup_t2_movw_lo16_pcrel:
     RelocType = unsigned(MachO::ARM_RELOC_HALF);
     Log2Size = 2;
     return true;
@@ -206,7 +202,6 @@ RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
   switch ((unsigned)Fixup.getKind()) {
   default: break;
   case ARM::fixup_arm_movt_hi16:
-  case ARM::fixup_arm_movt_hi16_pcrel:
     MovtBit = 1;
     // The thumb bit shouldn't be set in the 'other-half' bit of the
     // relocation, but it will be set in FixedValue if the base symbol
@@ -215,13 +210,11 @@ RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
       FixedValue &= 0xfffffffe;
     break;
   case ARM::fixup_t2_movt_hi16:
-  case ARM::fixup_t2_movt_hi16_pcrel:
     if (A_SD->getFlags() & SF_ThumbFunc)
       FixedValue &= 0xfffffffe;
     MovtBit = 1;
     // Fallthrough
   case ARM::fixup_t2_movw_lo16:
-  case ARM::fixup_t2_movw_lo16_pcrel:
     ThumbBit = 1;
     break;
   }
@@ -465,15 +458,11 @@ void ARMMachObjectWriter::RecordRelocation(MachObjectWriter *Writer,
     switch ((unsigned)Fixup.getKind()) {
     default: break;
     case ARM::fixup_arm_movw_lo16:
-    case ARM::fixup_arm_movw_lo16_pcrel:
     case ARM::fixup_t2_movw_lo16:
-    case ARM::fixup_t2_movw_lo16_pcrel:
       Value = (FixedValue >> 16) & 0xffff;
       break;
     case ARM::fixup_arm_movt_hi16:
-    case ARM::fixup_arm_movt_hi16_pcrel:
     case ARM::fixup_t2_movt_hi16:
-    case ARM::fixup_t2_movt_hi16_pcrel:
       Value = FixedValue & 0xffff;
       break;
     }

lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp

@@ -116,7 +116,8 @@ MCObjectWriter *MipsAsmBackend::createObjectWriter(raw_ostream &OS) const {
 /// data fragment, at the offset specified by the fixup and following the
 /// fixup kind as appropriate.
 void MipsAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
-                                unsigned DataSize, uint64_t Value) const {
+                                unsigned DataSize, uint64_t Value,
+                                bool IsPCRel) const {
   MCFixupKind Kind = Fixup.getKind();
   Value = adjustFixupValue(Fixup, Value);
 

lib/Target/Mips/MCTargetDesc/MipsAsmBackend.h

@@ -40,7 +40,7 @@ public:
   MCObjectWriter *createObjectWriter(raw_ostream &OS) const;
 
   void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                  uint64_t Value) const;
+                  uint64_t Value, bool IsPCRel) const;
 
   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const;
 

lib/Target/Mips/MCTargetDesc/MipsBaseInfo.h

@@ -120,34 +120,6 @@ namespace MipsII {
     FormMask = 15
   };
 }
-
-inline static std::pair<const MCSymbolRefExpr*, int64_t>
-MipsGetSymAndOffset(const MCFixup &Fixup) {
-  MCFixupKind FixupKind = Fixup.getKind();
-
-  if ((FixupKind < FirstTargetFixupKind) ||
-      (FixupKind >= MCFixupKind(Mips::LastTargetFixupKind)))
-    return std::make_pair((const MCSymbolRefExpr*)0, (int64_t)0);
-
-  const MCExpr *Expr = Fixup.getValue();
-  MCExpr::ExprKind Kind = Expr->getKind();
-
-  if (Kind == MCExpr::Binary) {
-    const MCBinaryExpr *BE = static_cast<const MCBinaryExpr*>(Expr);
-    const MCExpr *LHS = BE->getLHS();
-    const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(BE->getRHS());
-
-    if ((LHS->getKind() != MCExpr::SymbolRef) || !CE)
-      return std::make_pair((const MCSymbolRefExpr*)0, (int64_t)0);
-
-    return std::make_pair(cast<MCSymbolRefExpr>(LHS), CE->getValue());
-  }
-
-  if (Kind != MCExpr::SymbolRef)
-    return std::make_pair((const MCSymbolRefExpr*)0, (int64_t)0);
-
-  return std::make_pair(cast<MCSymbolRefExpr>(Expr), 0);
-}
 }
 
 #endif

lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp

@@ -21,17 +21,6 @@
 using namespace llvm;
 
 namespace {
-  struct RelEntry {
-    RelEntry(const ELFRelocationEntry &R, const MCSymbol *S, int64_t O) :
-      Reloc(R), Sym(S), Offset(O) {}
-    ELFRelocationEntry Reloc;
-    const MCSymbol *Sym;
-    int64_t Offset;
-  };
-
-  typedef std::list<RelEntry> RelLs;
-  typedef RelLs::iterator RelLsIter;
-
   class MipsELFObjectWriter : public MCELFObjectTargetWriter {
   public:
     MipsELFObjectWriter(bool _is64Bit, uint8_t OSABI,
@@ -41,13 +30,7 @@ namespace {
 
     unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                           bool IsPCRel) const override;
-    virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
+    bool needsRelocateWithSymbol(unsigned Type) const override;
-                                           const MCValue &Target,
-                                           const MCFragment &F,
-                                           const MCFixup &Fixup,
-                                           bool IsPCRel) const;
-    virtual void sortRelocs(const MCAssembler &Asm,
-                            std::vector<ELFRelocationEntry> &Relocs);
   };
 }
 
@@ -59,21 +42,6 @@ MipsELFObjectWriter::MipsELFObjectWriter(bool _is64Bit, uint8_t OSABI,
 
 MipsELFObjectWriter::~MipsELFObjectWriter() {}
 
-const MCSymbol *MipsELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
-                                                    const MCValue &Target,
-                                                    const MCFragment &F,
-                                                    const MCFixup &Fixup,
-                                                    bool IsPCRel) const {
-  assert(Target.getSymA() && "SymA cannot be 0.");
-  const MCSymbol &Sym = Target.getSymA()->getSymbol().AliasedSymbol();
-
-  if (Sym.getSection().getKind().isMergeableCString() ||
-      Sym.getSection().getKind().isMergeableConst())
-    return &Sym;
-
-  return NULL;
-}
-
 unsigned MipsELFObjectWriter::GetRelocType(const MCValue &Target,
                                            const MCFixup &Fixup,
                                            bool IsPCRel) const {
@@ -229,91 +197,23 @@ unsigned MipsELFObjectWriter::GetRelocType(const MCValue &Target,
   return Type;
 }
 
-// Return true if R is either a GOT16 against a local symbol or HI16.
+bool
-static bool NeedsMatchingLo(const MCAssembler &Asm, const RelEntry &R) {
+MipsELFObjectWriter::needsRelocateWithSymbol(unsigned Type) const {
-  if (!R.Sym)
+  // FIXME: This is extremelly conservative. This really needs to use a
+  // whitelist with a clear explanation for why each realocation needs to
+  // point to the symbol, not to the section.
+  switch (Type) {
+  default:
+    return true;
+
+  case ELF::R_MIPS_26:
+  case ELF::R_MIPS_LO16:
+  case ELF::R_MIPS_HI16:
+  case ELF::R_MIPS_32:
+  case ELF::R_MIPS_64:
+  case ELF::R_MIPS_GPREL16:
     return false;
-
-  MCSymbolData &SD = Asm.getSymbolData(R.Sym->AliasedSymbol());
-
-  return ((R.Reloc.Type == ELF::R_MIPS_GOT16) && !SD.isExternal()) ||
-    (R.Reloc.Type == ELF::R_MIPS_HI16);
-}
-
-static bool HasMatchingLo(const MCAssembler &Asm, RelLsIter I, RelLsIter Last) {
-  if (I == Last)
-    return false;
-
-  RelLsIter Hi = I++;
-
-  return (I->Reloc.Type == ELF::R_MIPS_LO16) && (Hi->Sym == I->Sym) &&
-    (Hi->Offset == I->Offset);
-}
-
-static bool HasSameSymbol(const RelEntry &R0, const RelEntry &R1) {
-  return R0.Sym == R1.Sym;
-}
-
-static int CompareOffset(const RelEntry &R0, const RelEntry &R1) {
-  return (R0.Offset > R1.Offset) ? 1 : ((R0.Offset == R1.Offset) ? 0 : -1);
-}
-
-void MipsELFObjectWriter::sortRelocs(const MCAssembler &Asm,
-                                     std::vector<ELFRelocationEntry> &Relocs) {
-  // Call the default function first. Relocations are sorted in descending
-  // order of r_offset.
-  MCELFObjectTargetWriter::sortRelocs(Asm, Relocs);
-
-  RelLs RelocLs;
-  std::vector<RelLsIter> Unmatched;
-
-  // Fill RelocLs. Traverse Relocs backwards so that relocations in RelocLs
-  // are in ascending order of r_offset.
-  for (std::vector<ELFRelocationEntry>::reverse_iterator R = Relocs.rbegin();
-       R != Relocs.rend(); ++R) {
-     std::pair<const MCSymbolRefExpr*, int64_t> P =
-       MipsGetSymAndOffset(*R->Fixup);
-     RelocLs.push_back(RelEntry(*R, P.first ? &P.first->getSymbol() : 0,
-                                P.second));
   }
-
-  // Get list of unmatched HI16 and GOT16.
-  for (RelLsIter R = RelocLs.begin(); R != RelocLs.end(); ++R)
-    if (NeedsMatchingLo(Asm, *R) && !HasMatchingLo(Asm, R, --RelocLs.end()))
-      Unmatched.push_back(R);
-
-  // Insert unmatched HI16 and GOT16 immediately before their matching LO16.
-  for (std::vector<RelLsIter>::iterator U = Unmatched.begin();
-       U != Unmatched.end(); ++U) {
-    RelLsIter LoPos = RelocLs.end(), HiPos = *U;
-    bool MatchedLo = false;
-
-    for (RelLsIter R = RelocLs.begin(); R != RelocLs.end(); ++R) {
-      if ((R->Reloc.Type == ELF::R_MIPS_LO16) && HasSameSymbol(*HiPos, *R) &&
-          (CompareOffset(*R, *HiPos) >= 0) &&
-          ((LoPos == RelocLs.end()) || ((CompareOffset(*R, *LoPos) < 0)) ||
-           (!MatchedLo && !CompareOffset(*R, *LoPos))))
-        LoPos = R;
-
-      MatchedLo = NeedsMatchingLo(Asm, *R) &&
-        HasMatchingLo(Asm, R, --RelocLs.end());
-    }
-
-    // If a matching LoPos was found, move HiPos and insert it before LoPos.
-    // Make the offsets of HiPos and LoPos match.
-    if (LoPos != RelocLs.end()) {
-      HiPos->Offset = LoPos->Offset;
-      RelocLs.insert(LoPos, *HiPos);
-      RelocLs.erase(HiPos);
-    }
-  }
-
-  // Put the sorted list back in reverse order.
-  assert(Relocs.size() == RelocLs.size());
-  unsigned I = RelocLs.size();
-
-  for (RelLsIter R = RelocLs.begin(); R != RelocLs.end(); ++R)
-    Relocs[--I] = R->Reloc;
 }
 
 MCObjectWriter *llvm::createMipsELFObjectWriter(raw_ostream &OS,

lib/Target/PowerPC/MCTargetDesc/PPCAsmBackend.cpp

@@ -110,7 +110,7 @@ public:
   }
 
   void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                  uint64_t Value) const {
+                  uint64_t Value, bool IsPCRel) const {
     Value = adjustFixupValue(Fixup.getKind(), Value);
     if (!Value) return;           // Doesn't change encoding.
 

lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp

@@ -30,14 +30,6 @@ namespace {
                                        bool IsPCRel) const;
     unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                           bool IsPCRel) const override;
-    virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
-                                           const MCValue &Target,
-                                           const MCFragment &F,
-                                           const MCFixup &Fixup,
-                                           bool IsPCRel) const;
-    virtual const MCSymbol *undefinedExplicitRelSym(const MCValue &Target,
-                                                    const MCFixup &Fixup,
-                                                    bool IsPCRel) const;
   };
 }
 
@@ -386,54 +378,6 @@ unsigned PPCELFObjectWriter::GetRelocType(const MCValue &Target,
   return getRelocTypeInner(Target, Fixup, IsPCRel);
 }
 
-const MCSymbol *PPCELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
-                                                   const MCValue &Target,
-                                                   const MCFragment &F,
-                                                   const MCFixup &Fixup,
-                                                   bool IsPCRel) const {
-  assert(Target.getSymA() && "SymA cannot be 0");
-  MCSymbolRefExpr::VariantKind Modifier = Fixup.getAccessVariant();
-
-  bool EmitThisSym;
-  switch (Modifier) {
-  // GOT references always need a relocation, even if the
-  // target symbol is local.
-  case MCSymbolRefExpr::VK_GOT:
-  case MCSymbolRefExpr::VK_PPC_GOT_LO:
-  case MCSymbolRefExpr::VK_PPC_GOT_HI:
-  case MCSymbolRefExpr::VK_PPC_GOT_HA:
-    EmitThisSym = true;
-    break;
-  default:
-    EmitThisSym = false;
-    break;
-  } 
-
-  if (EmitThisSym)
-    return &Target.getSymA()->getSymbol().AliasedSymbol();
-  return NULL;
-}
-
-const MCSymbol *PPCELFObjectWriter::undefinedExplicitRelSym(const MCValue &Target,
-                                                            const MCFixup &Fixup,
-                                                            bool IsPCRel) const {
-  assert(Target.getSymA() && "SymA cannot be 0");
-  const MCSymbol &Symbol = Target.getSymA()->getSymbol().AliasedSymbol();
-
-  unsigned RelocType = getRelocTypeInner(Target, Fixup, IsPCRel);
-
-  // The .odp creation emits a relocation against the symbol ".TOC." which
-  // create a R_PPC64_TOC relocation. However the relocation symbol name
-  // in final object creation should be NULL, since the symbol does not
-  // really exist, it is just the reference to TOC base for the current
-  // object file.
-  bool EmitThisSym = RelocType != ELF::R_PPC64_TOC;
-
-  if (EmitThisSym && !Symbol.isTemporary())
-    return &Symbol;
-  return NULL;
-}
-
 MCObjectWriter *llvm::createPPCELFObjectWriter(raw_ostream &OS,
                                                bool Is64Bit,
                                                bool IsLittleEndian,

lib/Target/R600/MCTargetDesc/AMDGPUAsmBackend.cpp

@@ -27,11 +27,10 @@ public:
                                         const MCAsmLayout &Layout) {
     //XXX: Implement if necessary.
   }
-  virtual void RecordRelocation(const MCAssembler &Asm,
+  void RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout,
-                                const MCAsmLayout &Layout,
+                        const MCFragment *Fragment, const MCFixup &Fixup,
-                                const MCFragment *Fragment,
+                        MCValue Target, bool &IsPCRel,
-                                const MCFixup &Fixup,
+                        uint64_t &FixedValue) override {
-                                MCValue Target, uint64_t &FixedValue) {
     assert(!"Not implemented");
   }
 
@@ -46,7 +45,7 @@ public:
 
   virtual unsigned getNumFixupKinds() const { return 0; };
   virtual void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                          uint64_t Value) const;
+                          uint64_t Value, bool IsPCRel) const;
   virtual bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
                                     const MCRelaxableFragment *DF,
                                     const MCAsmLayout &Layout) const {
@@ -71,7 +70,8 @@ void AMDGPUMCObjectWriter::WriteObject(MCAssembler &Asm,
 }
 
 void AMDGPUAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
-                                  unsigned DataSize, uint64_t Value) const {
+                                  unsigned DataSize, uint64_t Value,
+                                  bool IsPCRel) const {
 
   uint16_t *Dst = (uint16_t*)(Data + Fixup.getOffset());
   assert(Fixup.getKind() == FK_PCRel_4);

lib/Target/Sparc/MCTargetDesc/SparcAsmBackend.cpp

@@ -229,7 +229,7 @@ namespace {
       SparcAsmBackend(T), OSType(OSType) { }
 
     void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                    uint64_t Value) const {
+                    uint64_t Value, bool IsPCRel) const {
 
       Value = adjustFixupValue(Fixup.getKind(), Value);
       if (!Value) return;           // Doesn't change encoding.

lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp

@@ -30,12 +30,6 @@ namespace {
   protected:
     unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                           bool IsPCRel) const override;
-
-    virtual const MCSymbol *ExplicitRelSym(const MCAssembler &Asm,
-                                           const MCValue &Target,
-                                           const MCFragment &F,
-                                           const MCFixup &Fixup,
-                                           bool IsPCRel) const;
   };
 }
 
@@ -110,23 +104,6 @@ unsigned SparcELFObjectWriter::GetRelocType(const MCValue &Target,
   return ELF::R_SPARC_NONE;
 }
 
-const MCSymbol *SparcELFObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
-                                                     const MCValue &Target,
-                                                     const MCFragment &F,
-                                                     const MCFixup &Fixup,
-                                                     bool IsPCRel) const {
-
-  if (!Target.getSymA())
-    return NULL;
-  switch((unsigned)Fixup.getKind()) {
-  default: break;
-  case Sparc::fixup_sparc_got22:
-  case Sparc::fixup_sparc_got10:
-    return &Target.getSymA()->getSymbol().AliasedSymbol();
-  }
-  return NULL;
-}
-
 MCObjectWriter *llvm::createSparcELFObjectWriter(raw_ostream &OS,
                                                  bool Is64Bit,
                                                  uint8_t OSABI) {

lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp

@@ -48,7 +48,7 @@ public:
   }
   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
   void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                  uint64_t Value) const override;
+                  uint64_t Value, bool IsPCRel) const override;
   bool mayNeedRelaxation(const MCInst &Inst) const override {
     return false;
   }
@@ -85,7 +85,8 @@ SystemZMCAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
 }
 
 void SystemZMCAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
-                                     unsigned DataSize, uint64_t Value) const {
+                                     unsigned DataSize, uint64_t Value,
+                                     bool IsPCRel) const {
   MCFixupKind Kind = Fixup.getKind();
   unsigned Offset = Fixup.getOffset();
   unsigned Size = (getFixupKindInfo(Kind).TargetSize + 7) / 8;

lib/Target/SystemZ/MCTargetDesc/SystemZMCObjectWriter.cpp

@@ -26,9 +26,6 @@ protected:
   // Override MCELFObjectTargetWriter.
   unsigned GetRelocType(const MCValue &Target, const MCFixup &Fixup,
                         bool IsPCRel) const override;
-  const MCSymbol *ExplicitRelSym(const MCAssembler &Asm, const MCValue &Target,
-                                 const MCFragment &F, const MCFixup &Fixup,
-                                 bool IsPCRel) const override;
 };
 } // end anonymous namespace
 
@@ -111,21 +108,6 @@ unsigned SystemZObjectWriter::GetRelocType(const MCValue &Target,
   }
 }
 
-const MCSymbol *SystemZObjectWriter::ExplicitRelSym(const MCAssembler &Asm,
-                                                    const MCValue &Target,
-                                                    const MCFragment &F,
-                                                    const MCFixup &Fixup,
-                                                    bool IsPCRel) const {
-  // The addend in a PC-relative R_390_* relocation is always applied to
-  // the PC-relative part of the address.  If some kind of indirection
-  // is applied to the symbol first, we can't use an addend there too.
-  if (!Target.isAbsolute() &&
-      Target.getSymA()->getKind() != MCSymbolRefExpr::VK_None &&
-      IsPCRel)
-    return &Target.getSymA()->getSymbol().AliasedSymbol();
-  return NULL;
-}
-
 MCObjectWriter *llvm::createSystemZObjectWriter(raw_ostream &OS,
                                                 uint8_t OSABI) {
   MCELFObjectTargetWriter *MOTW = new SystemZObjectWriter(OSABI);

lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp

@@ -100,7 +100,7 @@ public:
   }
 
   void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
-                  uint64_t Value) const override {
+                  uint64_t Value, bool IsPCRel) const override {
     unsigned Size = 1 << getFixupKindLog2Size(Fixup.getKind());
 
     assert(Fixup.getOffset() + Size <= DataSize &&

test/MC/ARM/arm-elf-symver.s

@@ -24,16 +24,16 @@ global1:
 
 @ CHECK: Relocations [
 @ CHECK-NEXT:   Section (2) .rel.text {
-@ CHECK-NEXT:     0x0 R_ARM_ABS32 defined1 0x0
+@ CHECK-NEXT:     0x0 R_ARM_ABS32 .text 0x0
 @ CHECK-NEXT:     0x4 R_ARM_ABS32 bar2@zed 0x0
-@ CHECK-NEXT:     0x8 R_ARM_ABS32 defined2 0x0
+@ CHECK-NEXT:     0x8 R_ARM_ABS32 .text 0x0
-@ CHECK-NEXT:     0xC R_ARM_ABS32 defined3 0x0
+@ CHECK-NEXT:     0xC R_ARM_ABS32 .text 0x0
 @ CHECK-NEXT:     0x10 R_ARM_ABS32 bar6@zed 0x0
 @ CHECK-NEXT:   }
 @ CHECK-NEXT: ]
 
 @ CHECK:  Symbol {
-@ CHECK:    Name: bar1@zed (28)
+@ CHECK:    Name: bar1@zed
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Local (0x0)
@@ -42,7 +42,7 @@ global1:
 @ CHECK-NEXT:     Section: .text (0x1)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: bar3@@zed (46)
+@ CHECK-NEXT:     Name: bar3@@zed
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Local (0x0)
@@ -51,7 +51,7 @@ global1:
 @ CHECK-NEXT:     Section: .text (0x1)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: bar5@@zed (56)
+@ CHECK-NEXT:     Name: bar5@@zed
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Local (0x0)
@@ -60,7 +60,7 @@ global1:
 @ CHECK-NEXT:     Section: .text (0x1)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: defined1 (1)
+@ CHECK-NEXT:     Name: defined1
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Local (0x0)
@@ -69,16 +69,7 @@ global1:
 @ CHECK-NEXT:     Section: .text (0x1)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: defined2 (10)
+@ CHECK-NEXT:     Name: defined2
-@ CHECK-NEXT:     Value: 0x0
-@ CHECK-NEXT:     Size: 0
-@ CHECK-NEXT:     Binding: Local (0x0)
-@ CHECK-NEXT:     Type: None (0x0)
-@ CHECK-NEXT:     Other: 0
-@ CHECK-NEXT:     Section: .text (0x1)
-@ CHECK-NEXT:   }
-@ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: defined3 (19)
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Local (0x0)
@@ -114,7 +105,7 @@ global1:
 @ CHECK-NEXT:     Section: .bss (0x4)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: g1@@zed (88)
+@ CHECK-NEXT:     Name: g1@@zed
 @ CHECK-NEXT:     Value: 0x14
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Global (0x1)
@@ -123,7 +114,7 @@ global1:
 @ CHECK-NEXT:     Section: .text (0x1)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: global1 (80)
+@ CHECK-NEXT:     Name: global1
 @ CHECK-NEXT:     Value: 0x14
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Global (0x1)
@@ -132,7 +123,7 @@ global1:
 @ CHECK-NEXT:     Section: .text (0x1)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: bar2@zed (37)
+@ CHECK-NEXT:     Name: bar2@zed
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Global (0x1)
@@ -141,7 +132,7 @@ global1:
 @ CHECK-NEXT:     Section: Undefined (0x0)
 @ CHECK-NEXT:   }
 @ CHECK-NEXT:   Symbol {
-@ CHECK-NEXT:     Name: bar6@zed (66)
+@ CHECK-NEXT:     Name: bar6@zed
 @ CHECK-NEXT:     Value: 0x0
 @ CHECK-NEXT:     Size: 0
 @ CHECK-NEXT:     Binding: Global (0x1)

test/MC/ELF/bad-expr2.s

@@ -0,0 +1,12 @@
+// RUN: not llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o /dev/null \
+// RUN: 2>&1 | FileCheck %s
+
+// CHECK: No relocation available to represent this relative expression
+// CHECK: call foo - bar
+
+
+        call foo - bar
+        .section .foo
+foo:
+        .section .bar
+bar:

test/MC/ELF/bad-expr3.s

@@ -0,0 +1,10 @@
+// RUN: not llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o /dev/null \
+// RUN: 2>&1 | FileCheck %s
+
+// CHECK: Cannot represent a difference across sections
+
+        .long foo - bar
+        .section .zed
+foo:
+        .section .bah
+bar:

test/MC/ELF/merge.s

@@ -1,10 +1,7 @@
 // RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | llvm-readobj -r | FileCheck  %s
 
-// Test that PIC relocations with local symbols in a mergeable section are done
+// Test that relocations with local symbols in a mergeable section are done
-// with a reference to the symbol. Not sure if this is a linker limitation,
+// with a reference to the symbol if the offset is non zero.
-// but this matches the behavior of gas.
-
-// Non-PIC relocations with 0 offset don't use the symbol.
 
 
         movsd   .Lfoo(%rip), %xmm1
@@ -13,6 +10,7 @@
         jmp	foo@PLT
         movq 	foo@GOTPCREL, %rax
         movq    zed, %rax
+        movsd   .Lfoo+4(%rip), %xmm1
 
         .section        .sec1,"aM",@progbits,16
 .Lfoo:
@@ -30,5 +28,6 @@ foo:
 // CHECK-NEXT:     0x{{[^ ]+}} R_X86_64_PLT32    foo  0x{{[^ ]+}}
 // CHECK-NEXT:     0x{{[^ ]+}} R_X86_64_GOTPCREL foo  0x{{[^ ]+}}
 // CHECK-NEXT:     0x{{[^ ]+}} R_X86_64_32S      zed  0x{{[^ ]+}}
+// CHECK-NEXT:     0x{{[^ ]+}} R_X86_64_PC32    .sec1 0x{{[^ ]+}}
 // CHECK-NEXT:   }
 // CHECK-NEXT: ]

test/MC/ELF/relocation-386.s

@@ -5,7 +5,7 @@
 
 // CHECK:      Relocations [
 // CHECK-NEXT:   Section (2) .rel.text {
-// CHECK-NEXT:     0x2          R_386_GOTOFF     .Lfoo 0x0
+// CHECK-NEXT:     0x2          R_386_GOTOFF     .rodata.str1.16 0x0
 // CHECK-NEXT:     0x{{[^ ]+}}  R_386_PLT32      bar2 0x0
 // CHECK-NEXT:     0x{{[^ ]+}}  R_386_GOTPC      _GLOBAL_OFFSET_TABLE_ 0x0
 // Relocation 3 (bar3@GOTOFF) is done with symbol 7 (bss)
@@ -67,7 +67,7 @@
 
 // Symbol 4 is zed
 // CHECK:        Symbol {
-// CHECK:          Name: zed (53)
+// CHECK:          Name: zed
 // CHECK-NEXT:     Value: 0x0
 // CHECK-NEXT:     Size: 0
 // CHECK-NEXT:     Binding: Local

test/MC/ELF/relocation-pc.s

@@ -26,7 +26,7 @@
 // CHECK-NEXT:     AddressAlignment: 8
 // CHECK-NEXT:     EntrySize: 24
 // CHECK-NEXT:     Relocations [
-// CHECK-NEXT:       0x1 R_X86_64_PC8 - 0x0
+// CHECK-NEXT:       0x1 R_X86_64_PC8 - 0xFFFFFFFFFFFFFFFF
-// CHECK-NEXT:       0x3 R_X86_64_PC32 - 0x0
+// CHECK-NEXT:       0x3 R_X86_64_PC32 - 0xFFFFFFFFFFFFFEFC
 // CHECK-NEXT:     ]
 // CHECK-NEXT:   }