Move TLOF implementations to libCodegen to resolve layering violation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96288 91177308-0d34-0410-b5e6-96231b3b80d8

18 files changed, 1091 insertions, 1025 deletions

diff --git a/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h b/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h
new file mode 100644
index 0000000000..c5aa626a46
--- /dev/null
+++ b/include/llvm/CodeGen/TargetLoweringObjectFileImpl.h
@@ -0,0 +1,202 @@
+//==-- llvm/CodeGen/TargetLoweringObjectFileImpl.h - Object Info -*- C++ -*-==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements classes used to handle lowerings specific to common
+// object file formats.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H
+#define LLVM_CODEGEN_TARGETLOWERINGOBJECTFILEIMPL_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/MC/SectionKind.h"
+#include "llvm/Target/TargetLoweringObjectFile.h"
+
+namespace llvm {
+  class MachineModuleInfo;
+  class Mangler;
+  class MCAsmInfo;
+  class MCExpr;
+  class MCSection;
+  class MCSectionMachO;
+  class MCSymbol;
+  class MCContext;
+  class GlobalValue;
+  class TargetMachine;
+
+
+class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {
+  mutable void *UniquingMap;
+protected:
+  /// TLSDataSection - Section directive for Thread Local data.
+  ///
+  const MCSection *TLSDataSection;        // Defaults to ".tdata".
+
+  /// TLSBSSSection - Section directive for Thread Local uninitialized data.
+  /// Null if this target doesn't support a BSS section.
+  ///
+  const MCSection *TLSBSSSection;         // Defaults to ".tbss".
+
+  const MCSection *DataRelSection;
+  const MCSection *DataRelLocalSection;
+  const MCSection *DataRelROSection;
+  const MCSection *DataRelROLocalSection;
+
+  const MCSection *MergeableConst4Section;
+  const MCSection *MergeableConst8Section;
+  const MCSection *MergeableConst16Section;
+
+protected:
+  const MCSection *getELFSection(StringRef Section, unsigned Type,
+                                 unsigned Flags, SectionKind Kind,
+                                 bool IsExplicit = false) const;
+public:
+  TargetLoweringObjectFileELF() : UniquingMap(0) {}
+  ~TargetLoweringObjectFileELF();
+
+  virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
+
+  const MCSection *getDataRelSection() const { return DataRelSection; }
+
+  /// getSectionForConstant - Given a constant with the SectionKind, return a
+  /// section that it should be placed in.
+  virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
+
+
+  virtual const MCSection *
+  getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
+                           Mangler *Mang, const TargetMachine &TM) const;
+
+  virtual const MCSection *
+  SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+                         Mangler *Mang, const TargetMachine &TM) const;
+
+  /// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a reference
+  /// to the specified global variable from exception handling information.
+  ///
+  virtual const MCExpr *
+  getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
+                              MachineModuleInfo *MMI, unsigned Encoding) const;
+};
+
+
+
+class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {
+  mutable void *UniquingMap;
+
+  const MCSection *CStringSection;
+  const MCSection *UStringSection;
+  const MCSection *TextCoalSection;
+  const MCSection *ConstTextCoalSection;
+  const MCSection *ConstDataCoalSection;
+  const MCSection *ConstDataSection;
+  const MCSection *DataCoalSection;
+  const MCSection *DataCommonSection;
+  const MCSection *DataBSSSection;
+  const MCSection *FourByteConstantSection;
+  const MCSection *EightByteConstantSection;
+  const MCSection *SixteenByteConstantSection;
+
+  const MCSection *LazySymbolPointerSection;
+  const MCSection *NonLazySymbolPointerSection;
+public:
+  TargetLoweringObjectFileMachO() : UniquingMap(0) {}
+  ~TargetLoweringObjectFileMachO();
+
+  virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
+
+  virtual const MCSection *
+  SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+                         Mangler *Mang, const TargetMachine &TM) const;
+
+  virtual const MCSection *
+  getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
+                           Mangler *Mang, const TargetMachine &TM) const;
+
+  virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
+
+  /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively
+  /// decide not to emit the UsedDirective for some symbols in llvm.used.
+  /// FIXME: REMOVE this (rdar://7071300)
+  virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
+                                          Mangler *) const;
+
+  /// getMachOSection - Return the MCSection for the specified mach-o section.
+  /// This requires the operands to be valid.
+  const MCSectionMachO *getMachOSection(StringRef Segment,
+                                        StringRef Section,
+                                        unsigned TypeAndAttributes,
+                                        SectionKind K) const {
+    return getMachOSection(Segment, Section, TypeAndAttributes, 0, K);
+  }
+  const MCSectionMachO *getMachOSection(StringRef Segment,
+                                        StringRef Section,
+                                        unsigned TypeAndAttributes,
+                                        unsigned Reserved2,
+                                        SectionKind K) const;
+
+  /// getTextCoalSection - Return the "__TEXT,__textcoal_nt" section we put weak
+  /// text symbols into.
+  const MCSection *getTextCoalSection() const {
+    return TextCoalSection;
+  }
+
+  /// getConstTextCoalSection - Return the "__TEXT,__const_coal" section
+  /// we put weak read-only symbols into.
+  const MCSection *getConstTextCoalSection() const {
+    return ConstTextCoalSection;
+  }
+
+  /// getLazySymbolPointerSection - Return the section corresponding to
+  /// the .lazy_symbol_pointer directive.
+  const MCSection *getLazySymbolPointerSection() const {
+    return LazySymbolPointerSection;
+  }
+
+  /// getNonLazySymbolPointerSection - Return the section corresponding to
+  /// the .non_lazy_symbol_pointer directive.
+  const MCSection *getNonLazySymbolPointerSection() const {
+    return NonLazySymbolPointerSection;
+  }
+
+  /// getSymbolForDwarfGlobalReference - The mach-o version of this method
+  /// defaults to returning a stub reference.
+  virtual const MCExpr *
+  getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
+                              MachineModuleInfo *MMI, unsigned Encoding) const;
+};
+
+
+
+class TargetLoweringObjectFileCOFF : public TargetLoweringObjectFile {
+  mutable void *UniquingMap;
+public:
+  TargetLoweringObjectFileCOFF() : UniquingMap(0) {}
+  ~TargetLoweringObjectFileCOFF();
+
+  virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
+
+  virtual const MCSection *
+  getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
+                           Mangler *Mang, const TargetMachine &TM) const;
+
+  virtual const MCSection *
+  SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+                         Mangler *Mang, const TargetMachine &TM) const;
+
+  /// getCOFFSection - Return the MCSection for the specified COFF section.
+  /// FIXME: Switch this to a semantic view eventually.
+  const MCSection *getCOFFSection(StringRef Name, bool isDirective,
+                                  SectionKind K) const;
+};
+
+} // end namespace llvm
+
+#endif
diff --git a/include/llvm/Target/TargetLoweringObjectFile.h b/include/llvm/Target/TargetLoweringObjectFile.h
index a2f8c75647..42d88a00a5 100644
--- a/include/llvm/Target/TargetLoweringObjectFile.h
+++ b/include/llvm/Target/TargetLoweringObjectFile.h
@@ -197,174 +197,6 @@ protected:
   SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
                          Mangler *Mang, const TargetMachine &TM) const;
 };
-  
-  
-  
-
-class TargetLoweringObjectFileELF : public TargetLoweringObjectFile {
-  mutable void *UniquingMap;
-protected:
-  /// TLSDataSection - Section directive for Thread Local data.
-  ///
-  const MCSection *TLSDataSection;        // Defaults to ".tdata".
-  
-  /// TLSBSSSection - Section directive for Thread Local uninitialized data.
-  /// Null if this target doesn't support a BSS section.
-  ///
-  const MCSection *TLSBSSSection;         // Defaults to ".tbss".
-  
-  const MCSection *DataRelSection;
-  const MCSection *DataRelLocalSection;
-  const MCSection *DataRelROSection;
-  const MCSection *DataRelROLocalSection;
-  
-  const MCSection *MergeableConst4Section;
-  const MCSection *MergeableConst8Section;
-  const MCSection *MergeableConst16Section;
-  
-protected:
-  const MCSection *getELFSection(StringRef Section, unsigned Type, 
-                                 unsigned Flags, SectionKind Kind,
-                                 bool IsExplicit = false) const;
-public:
-  TargetLoweringObjectFileELF() : UniquingMap(0) {}
-  ~TargetLoweringObjectFileELF();
-  
-  virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
-
-  const MCSection *getDataRelSection() const { return DataRelSection; }
-
-  /// getSectionForConstant - Given a constant with the SectionKind, return a
-  /// section that it should be placed in.
-  virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
-  
-  
-  virtual const MCSection *
-  getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind, 
-                           Mangler *Mang, const TargetMachine &TM) const;
-  
-  virtual const MCSection *
-  SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
-                         Mangler *Mang, const TargetMachine &TM) const;
-
-  /// getSymbolForDwarfGlobalReference - Return an MCExpr to use for a reference
-  /// to the specified global variable from exception handling information.
-  ///
-  virtual const MCExpr *
-  getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
-                              MachineModuleInfo *MMI, unsigned Encoding) const;
-};
-
-  
-  
-class TargetLoweringObjectFileMachO : public TargetLoweringObjectFile {
-  mutable void *UniquingMap;
-  
-  const MCSection *CStringSection;
-  const MCSection *UStringSection;
-  const MCSection *TextCoalSection;
-  const MCSection *ConstTextCoalSection;
-  const MCSection *ConstDataCoalSection;
-  const MCSection *ConstDataSection;
-  const MCSection *DataCoalSection;
-  const MCSection *DataCommonSection;
-  const MCSection *DataBSSSection;
-  const MCSection *FourByteConstantSection;
-  const MCSection *EightByteConstantSection;
-  const MCSection *SixteenByteConstantSection;
-  
-  const MCSection *LazySymbolPointerSection;
-  const MCSection *NonLazySymbolPointerSection;
-public:
-  TargetLoweringObjectFileMachO() : UniquingMap(0) {}
-  ~TargetLoweringObjectFileMachO();
-  
-  virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
-
-  virtual const MCSection *
-  SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
-                         Mangler *Mang, const TargetMachine &TM) const;
-  
-  virtual const MCSection *
-  getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind, 
-                           Mangler *Mang, const TargetMachine &TM) const;
-  
-  virtual const MCSection *getSectionForConstant(SectionKind Kind) const;
-  
-  /// shouldEmitUsedDirectiveFor - This hook allows targets to selectively
-  /// decide not to emit the UsedDirective for some symbols in llvm.used.
-  /// FIXME: REMOVE this (rdar://7071300)
-  virtual bool shouldEmitUsedDirectiveFor(const GlobalValue *GV,
-                                          Mangler *) const;
-
-  /// getMachOSection - Return the MCSection for the specified mach-o section.
-  /// This requires the operands to be valid.
-  const MCSectionMachO *getMachOSection(StringRef Segment,
-                                        StringRef Section,
-                                        unsigned TypeAndAttributes,
-                                        SectionKind K) const {
-    return getMachOSection(Segment, Section, TypeAndAttributes, 0, K);
-  }
-  const MCSectionMachO *getMachOSection(StringRef Segment,
-                                        StringRef Section,
-                                        unsigned TypeAndAttributes,
-                                        unsigned Reserved2,
-                                        SectionKind K) const;
-
-  /// getTextCoalSection - Return the "__TEXT,__textcoal_nt" section we put weak
-  /// text symbols into.
-  const MCSection *getTextCoalSection() const {
-    return TextCoalSection;
-  }
-  
-  /// getConstTextCoalSection - Return the "__TEXT,__const_coal" section
-  /// we put weak read-only symbols into.
-  const MCSection *getConstTextCoalSection() const {
-    return ConstTextCoalSection;
-  }
-  
-  /// getLazySymbolPointerSection - Return the section corresponding to
-  /// the .lazy_symbol_pointer directive.
-  const MCSection *getLazySymbolPointerSection() const {
-    return LazySymbolPointerSection;
-  }
-  
-  /// getNonLazySymbolPointerSection - Return the section corresponding to
-  /// the .non_lazy_symbol_pointer directive.
-  const MCSection *getNonLazySymbolPointerSection() const {
-    return NonLazySymbolPointerSection;
-  }
-  
-  /// getSymbolForDwarfGlobalReference - The mach-o version of this method
-  /// defaults to returning a stub reference.
-  virtual const MCExpr *
-  getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
-                              MachineModuleInfo *MMI, unsigned Encoding) const;
-};
-
-
-
-class TargetLoweringObjectFileCOFF : public TargetLoweringObjectFile {
-  mutable void *UniquingMap;
-public:
-  TargetLoweringObjectFileCOFF() : UniquingMap(0) {}
-  ~TargetLoweringObjectFileCOFF();
-  
-  virtual void Initialize(MCContext &Ctx, const TargetMachine &TM);
-  
-  virtual const MCSection *
-  getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind, 
-                           Mangler *Mang, const TargetMachine &TM) const;
-  
-  virtual const MCSection *
-  SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
-                         Mangler *Mang, const TargetMachine &TM) const;
-
-  /// getCOFFSection - Return the MCSection for the specified COFF section.
-  /// FIXME: Switch this to a semantic view eventually.
-  const MCSection *getCOFFSection(StringRef Name, bool isDirective,
-                                  SectionKind K) const;
-};
 
 } // end namespace llvm
 
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
new file mode 100644
index 0000000000..190b533237
--- /dev/null
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -0,0 +1,874 @@
+//===-- llvm/CodeGen/TargetLoweringObjectFileImpl.cpp - Object File Info --===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements classes used to handle lowerings specific to common
+// object file formats.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/CodeGen/MachineModuleInfoImpls.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSectionMachO.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Target/Mangler.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+//                                  ELF
+//===----------------------------------------------------------------------===//
+typedef StringMap<const MCSectionELF*> ELFUniqueMapTy;
+
+TargetLoweringObjectFileELF::~TargetLoweringObjectFileELF() {
+  // If we have the section uniquing map, free it.
+  delete (ELFUniqueMapTy*)UniquingMap;
+}
+
+const MCSection *TargetLoweringObjectFileELF::
+getELFSection(StringRef Section, unsigned Type, unsigned Flags,
+              SectionKind Kind, bool IsExplicit) const {
+  if (UniquingMap == 0)
+    UniquingMap = new ELFUniqueMapTy();
+  ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)UniquingMap;
+
+  // Do the lookup, if we have a hit, return it.
+  const MCSectionELF *&Entry = Map[Section];
+  if (Entry) return Entry;
+
+  return Entry = MCSectionELF::Create(Section, Type, Flags, Kind, IsExplicit,
+                                      getContext());
+}
+
+void TargetLoweringObjectFileELF::Initialize(MCContext &Ctx,
+                                             const TargetMachine &TM) {
+  if (UniquingMap != 0)
+    ((ELFUniqueMapTy*)UniquingMap)->clear();
+  TargetLoweringObjectFile::Initialize(Ctx, TM);
+
+  BSSSection =
+    getELFSection(".bss", MCSectionELF::SHT_NOBITS,
+                  MCSectionELF::SHF_WRITE | MCSectionELF::SHF_ALLOC,
+                  SectionKind::getBSS());
+
+  TextSection =
+    getELFSection(".text", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_EXECINSTR | MCSectionELF::SHF_ALLOC,
+                  SectionKind::getText());
+
+  DataSection =
+    getELFSection(".data", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_WRITE | MCSectionELF::SHF_ALLOC,
+                  SectionKind::getDataRel());
+
+  ReadOnlySection =
+    getELFSection(".rodata", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC,
+                  SectionKind::getReadOnly());
+
+  TLSDataSection =
+    getELFSection(".tdata", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_TLS |
+                  MCSectionELF::SHF_WRITE, SectionKind::getThreadData());
+
+  TLSBSSSection =
+    getELFSection(".tbss", MCSectionELF::SHT_NOBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_TLS |
+                  MCSectionELF::SHF_WRITE, SectionKind::getThreadBSS());
+
+  DataRelSection =
+    getELFSection(".data.rel", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getDataRel());
+
+  DataRelLocalSection =
+    getELFSection(".data.rel.local", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getDataRelLocal());
+
+  DataRelROSection =
+    getELFSection(".data.rel.ro", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getReadOnlyWithRel());
+
+  DataRelROLocalSection =
+    getELFSection(".data.rel.ro.local", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getReadOnlyWithRelLocal());
+
+  MergeableConst4Section =
+    getELFSection(".rodata.cst4", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
+                  SectionKind::getMergeableConst4());
+
+  MergeableConst8Section =
+    getELFSection(".rodata.cst8", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
+                  SectionKind::getMergeableConst8());
+
+  MergeableConst16Section =
+    getELFSection(".rodata.cst16", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_MERGE,
+                  SectionKind::getMergeableConst16());
+
+  StaticCtorSection =
+    getELFSection(".ctors", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getDataRel());
+
+  StaticDtorSection =
+    getELFSection(".dtors", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getDataRel());
+
+  // Exception Handling Sections.
+
+  // FIXME: We're emitting LSDA info into a readonly section on ELF, even though
+  // it contains relocatable pointers.  In PIC mode, this is probably a big
+  // runtime hit for C++ apps.  Either the contents of the LSDA need to be
+  // adjusted or this should be a data section.
+  LSDASection =
+    getELFSection(".gcc_except_table", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC, SectionKind::getReadOnly());
+  EHFrameSection =
+    getELFSection(".eh_frame", MCSectionELF::SHT_PROGBITS,
+                  MCSectionELF::SHF_ALLOC | MCSectionELF::SHF_WRITE,
+                  SectionKind::getDataRel());
+
+  // Debug Info Sections.
+  DwarfAbbrevSection =
+    getELFSection(".debug_abbrev", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfInfoSection =
+    getELFSection(".debug_info", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfLineSection =
+    getELFSection(".debug_line", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfFrameSection =
+    getELFSection(".debug_frame", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfPubNamesSection =
+    getELFSection(".debug_pubnames", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfPubTypesSection =
+    getELFSection(".debug_pubtypes", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfStrSection =
+    getELFSection(".debug_str", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfLocSection =
+    getELFSection(".debug_loc", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfARangesSection =
+    getELFSection(".debug_aranges", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfRangesSection =
+    getELFSection(".debug_ranges", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+  DwarfMacroInfoSection =
+    getELFSection(".debug_macinfo", MCSectionELF::SHT_PROGBITS, 0,
+                  SectionKind::getMetadata());
+}
+
+
+static SectionKind
+getELFKindForNamedSection(StringRef Name, SectionKind K) {
+  if (Name.empty() || Name[0] != '.') return K;
+
+  // Some lame default implementation based on some magic section names.
+  if (Name == ".bss" ||
+      Name.startswith(".bss.") ||
+      Name.startswith(".gnu.linkonce.b.") ||
+      Name.startswith(".llvm.linkonce.b.") ||
+      Name == ".sbss" ||
+      Name.startswith(".sbss.") ||
+      Name.startswith(".gnu.linkonce.sb.") ||
+      Name.startswith(".llvm.linkonce.sb."))
+    return SectionKind::getBSS();
+
+  if (Name == ".tdata" ||
+      Name.startswith(".tdata.") ||
+      Name.startswith(".gnu.linkonce.td.") ||
+      Name.startswith(".llvm.linkonce.td."))
+    return SectionKind::getThreadData();
+
+  if (Name == ".tbss" ||
+      Name.startswith(".tbss.") ||
+      Name.startswith(".gnu.linkonce.tb.") ||
+      Name.startswith(".llvm.linkonce.tb."))
+    return SectionKind::getThreadBSS();
+
+  return K;
+}
+
+
+static unsigned getELFSectionType(StringRef Name, SectionKind K) {
+
+  if (Name == ".init_array")
+    return MCSectionELF::SHT_INIT_ARRAY;
+
+  if (Name == ".fini_array")
+    return MCSectionELF::SHT_FINI_ARRAY;
+
+  if (Name == ".preinit_array")
+    return MCSectionELF::SHT_PREINIT_ARRAY;
+
+  if (K.isBSS() || K.isThreadBSS())
+    return MCSectionELF::SHT_NOBITS;
+
+  return MCSectionELF::SHT_PROGBITS;
+}
+
+
+static unsigned
+getELFSectionFlags(SectionKind K) {
+  unsigned Flags = 0;
+
+  if (!K.isMetadata())
+    Flags |= MCSectionELF::SHF_ALLOC;
+
+  if (K.isText())
+    Flags |= MCSectionELF::SHF_EXECINSTR;
+
+  if (K.isWriteable())
+    Flags |= MCSectionELF::SHF_WRITE;
+
+  if (K.isThreadLocal())
+    Flags |= MCSectionELF::SHF_TLS;
+
+  // K.isMergeableConst() is left out to honour PR4650
+  if (K.isMergeableCString() || K.isMergeableConst4() ||
+      K.isMergeableConst8() || K.isMergeableConst16())
+    Flags |= MCSectionELF::SHF_MERGE;
+
+  if (K.isMergeableCString())
+    Flags |= MCSectionELF::SHF_STRINGS;
+
+  return Flags;
+}
+
+
+const MCSection *TargetLoweringObjectFileELF::
+getExplicitSectionGlobal(const GlobalValue *GV, SectionKind Kind,
+                         Mangler *Mang, const TargetMachine &TM) const {
+  StringRef SectionName = GV->getSection();
+
+  // Infer section flags from the section name if we can.
+  Kind = getELFKindForNamedSection(SectionName, Kind);
+
+  return getELFSection(SectionName,
+                       getELFSectionType(SectionName, Kind),
+                       getELFSectionFlags(Kind), Kind, true);
+}
+
+static const char *getSectionPrefixForUniqueGlobal(SectionKind Kind) {
+  if (Kind.isText())                 return ".gnu.linkonce.t.";
+  if (Kind.isReadOnly())             return ".gnu.linkonce.r.";
+
+  if (Kind.isThreadData())           return ".gnu.linkonce.td.";
+  if (Kind.isThreadBSS())            return ".gnu.linkonce.tb.";
+
+  if (Kind.isDataNoRel())            return ".gnu.linkonce.d.";
+  if (Kind.isDataRelLocal())         return ".gnu.linkonce.d.rel.local.";
+  if (Kind.isDataRel())              return ".gnu.linkonce.d.rel.";
+  if (Kind.isReadOnlyWithRelLocal()) return ".gnu.linkonce.d.rel.ro.local.";
+
+  assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+  return ".gnu.linkonce.d.rel.ro.";
+}
+
+const MCSection *TargetLoweringObjectFileELF::
+SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+                       Mangler *Mang, const TargetMachine &TM) const {
+
+  // If this global is linkonce/weak and the target handles this by emitting it
+  // into a 'uniqued' section name, create and return the section now.
+  if (GV->isWeakForLinker() && !Kind.isCommon() && !Kind.isBSS()) {
+    const char *Prefix = getSectionPrefixForUniqueGlobal(Kind);
+    SmallString<128> Name;
+    Name.append(Prefix, Prefix+strlen(Prefix));
+    Mang->getNameWithPrefix(Name, GV, false);
+    return getELFSection(Name.str(), getELFSectionType(Name.str(), Kind),
+                         getELFSectionFlags(Kind), Kind);
+  }
+
+  if (Kind.isText()) return TextSection;
+
+  if (Kind.isMergeable1ByteCString() ||
+      Kind.isMergeable2ByteCString() ||
+      Kind.isMergeable4ByteCString()) {
+
+    // We also need alignment here.
+    // FIXME: this is getting the alignment of the character, not the
+    // alignment of the global!
+    unsigned Align =
+      TM.getTargetData()->getPreferredAlignment(cast<GlobalVariable>(GV));
+
+    const char *SizeSpec = ".rodata.str1.";
+    if (Kind.isMergeable2ByteCString())
+      SizeSpec = ".rodata.str2.";
+    else if (Kind.isMergeable4ByteCString())
+      SizeSpec = ".rodata.str4.";
+    else
+      assert(Kind.isMergeable1ByteCString() && "unknown string width");
+
+
+    std::string Name = SizeSpec + utostr(Align);
+    return getELFSection(Name, MCSectionELF::SHT_PROGBITS,
+                         MCSectionELF::SHF_ALLOC |
+                         MCSectionELF::SHF_MERGE |
+                         MCSectionELF::SHF_STRINGS,
+                         Kind);
+  }
+
+  if (Kind.isMergeableConst()) {
+    if (Kind.isMergeableConst4() && MergeableConst4Section)
+      return MergeableConst4Section;
+    if (Kind.isMergeableConst8() && MergeableConst8Section)
+      return MergeableConst8Section;
+    if (Kind.isMergeableConst16() && MergeableConst16Section)
+      return MergeableConst16Section;
+    return ReadOnlySection;  // .const
+  }
+
+  if (Kind.isReadOnly())             return ReadOnlySection;
+
+  if (Kind.isThreadData())           return TLSDataSection;
+  if (Kind.isThreadBSS())            return TLSBSSSection;
+
+  // Note: we claim that common symbols are put in BSSSection, but they are
+  // really emitted with the magic .comm directive, which creates a symbol table
+  // entry but not a section.
+  if (Kind.isBSS() || Kind.isCommon()) return BSSSection;
+
+  if (Kind.isDataNoRel())            return DataSection;
+  if (Kind.isDataRelLocal())         return DataRelLocalSection;
+  if (Kind.isDataRel())              return DataRelSection;
+  if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
+
+  assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+  return DataRelROSection;
+}
+
+/// getSectionForConstant - Given a mergeable constant with the
+/// specified size and relocation information, return a section that it
+/// should be placed in.
+const MCSection *TargetLoweringObjectFileELF::
+getSectionForConstant(SectionKind Kind) const {
+  if (Kind.isMergeableConst4() && MergeableConst4Section)
+    return MergeableConst4Section;
+  if (Kind.isMergeableConst8() && MergeableConst8Section)
+    return MergeableConst8Section;
+  if (Kind.isMergeableConst16() && MergeableConst16Section)
+    return MergeableConst16Section;
+  if (Kind.isReadOnly())
+    return ReadOnlySection;
+
+  if (Kind.isReadOnlyWithRelLocal()) return DataRelROLocalSection;
+  assert(Kind.isReadOnlyWithRel() && "Unknown section kind");
+  return DataRelROSection;
+}
+
+const MCExpr *TargetLoweringObjectFileELF::
+getSymbolForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
+                             MachineModuleInfo *MMI, unsigned Encoding) const {
+
+  if (Encoding & dwarf::DW_EH_PE_indirect) {
+    MachineModuleInfoELF &ELFMMI = MMI->getObjFileInfo<MachineModuleInfoELF>();
+
+    SmallString<128> Name;
+    Mang->getNameWithPrefix(Name, GV, true);
+    Name += ".DW.stub";
+
+    // Add information about the stub reference to ELFMMI so that the stub
+    // gets emitted by the asmprinter.
+    MCSymbol *Sym = getContext().GetOrCreateSymbol(Name.str());
+    MCSymbol *&StubSym = ELFMMI.getGVStubEntry(Sym);
+    if (StubSym == 0) {
+      Name.clear();
+      Mang->getNameWithPrefix(Name, GV, false);
+      StubSym = getContext().GetOrCreateSymbol(Name.str());
+    }
+
+    return TargetLoweringObjectFile::
+      getSymbolForDwarfReference(Sym, MMI,
+                                 Encoding & ~dwarf::DW_EH_PE_indirect);
+  }
+
+  return TargetLoweringObjectFile::
+    getSymbolForDwarfGlobalReference(GV, Mang, MMI, Encoding);
+}
+
+//===----------------------------------------------------------------------===//
+//                                 MachO
+//===----------------------------------------------------------------------===//
+
+typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
+
+TargetLoweringObjectFileMachO::~TargetLoweringObjectFileMachO() {
+  // If we have the MachO uniquing map, free it.
+  delete (MachOUniqueMapTy*)UniquingMap;
+}
+
+
+const MCSectionMachO *TargetLoweringObjectFileMachO::
+getMachOSection(StringRef Segment, StringRef Section,
+                unsigned TypeAndAttributes,
+                unsigned Reserved2, SectionKind Kind) const {
+  // We unique sections by their segment/section pair.  The returned section
+  // may not have the same flags as the requested section, if so this should be
+  // diagnosed by the client as