[llvm-readobj][ELF] New `llvm-readobj` command line option `-mips-plt-got` to print a MIPS .got section

[atanasyan]

Summary

This patch adds to llvm-readobj a new command line option -mips-plt-got for printing a MIPS .got section. This option exists in the readelf tool but missed in the llvm-readobj.

[• rafael]

tools/llvm-readobj/ELFDumper.cpp

83

Can this be static?

690

Can this be static.

700–701

This is a refactoring, no? Can you split it?

702–703

This part too.

[atanasyan]

1. Refactored some code by the separate commit rL210509.
2. The findSectionByAddress() is a static function now.

[atanasyan]

Ping?

[• rafael]

LGTM in that this is now fully MIPS specific.

Is there any documentation about this format that you can put a link to in the comments.

tools/llvm-readobj/ELFDumper.cpp

1056

Style, start with a lowercase.

[atanasyan]

Thanks for review.

Closed by commit rL211150.

test/tools/llvm-readobj/mips-got.test

+RUN: llvm-readobj -mips-plt-got %p/Inputs/relocs.obj.elf-mips | \
+RUN:   FileCheck %s -check-prefix GOT-OBJ
+RUN: llvm-readobj -mips-plt-got %p/Inputs/dynamic-table-exe.mips | \
+RUN:   FileCheck %s -check-prefix GOT-EXE
+RUN: llvm-readobj -mips-plt-got %p/Inputs/dynamic-table-so.mips | \
+RUN:   FileCheck %s -check-prefix GOT-SO
+RUN: llvm-readobj -mips-plt-got %p/Inputs/got-tls.so.elf-mips64el | \
+RUN:   FileCheck %s -check-prefix GOT-TLS
+
+GOT-OBJ: Cannot find PLTGOT dynamic table tag.
+
+GOT-EXE:      Primary GOT {
+GOT-EXE-NEXT:   Canonical gp value: 0x418880
+GOT-EXE-NEXT:   Reserved entries [
+GOT-EXE-NEXT:     Entry {
+GOT-EXE-NEXT:       Address: 0x410890
+GOT-EXE-NEXT:       Access: -32752
+GOT-EXE-NEXT:       Initial: 0x0
+GOT-EXE-NEXT:       Purpose: Lazy resolver
+GOT-EXE-NEXT:     }
+GOT-EXE-NEXT:     Entry {
+GOT-EXE-NEXT:       Address: 0x410894
+GOT-EXE-NEXT:       Access: -32748
+GOT-EXE-NEXT:       Initial: 0x80000000
+GOT-EXE-NEXT:       Purpose: Module pointer (GNU extension)
+GOT-EXE-NEXT:     }
+GOT-EXE-NEXT:   ]
+GOT-EXE-NEXT:   Local entries [
+GOT-EXE-NEXT:     Entry {
+GOT-EXE-NEXT:       Address: 0x410898
+GOT-EXE-NEXT:       Access: -32744
+GOT-EXE-NEXT:       Initial: 0x400418
+GOT-EXE-NEXT:     }
+GOT-EXE-NEXT:     Entry {
+GOT-EXE-NEXT:       Address: 0x41089C
+GOT-EXE-NEXT:       Access: -32740
+GOT-EXE-NEXT:       Initial: 0x410840
+GOT-EXE-NEXT:     }
+GOT-EXE-NEXT:     Entry {
+GOT-EXE-NEXT:       Address: 0x4108A0
+GOT-EXE-NEXT:       Access: -32736
+GOT-EXE-NEXT:       Initial: 0x0
+GOT-EXE-NEXT:     }
+GOT-EXE-NEXT:   ]
+GOT-EXE-NEXT:   Global entries [
+GOT-EXE-NEXT:     Entry {
+GOT-EXE-NEXT:       Address: 0x4108A4
+GOT-EXE-NEXT:       Access: -32732
+GOT-EXE-NEXT:       Initial: 0x0
+GOT-EXE-NEXT:       Value: 0x0
+GOT-EXE-NEXT:       Type: Function (0x2)
+GOT-EXE-NEXT:       Section: Undefined (0x0)
+GOT-EXE-NEXT:       Name: __gmon_start__@ (1)
+GOT-EXE-NEXT:     }
+GOT-EXE-NEXT:   ]
+GOT-EXE-NEXT:   Number of TLS and multi-GOT entries: 0
+GOT-EXE-NEXT: }
+
+GOT-SO:      Primary GOT {
+GOT-SO-NEXT:   Canonical gp value: 0x188D0
+GOT-SO-NEXT:   Reserved entries [
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108E0
+GOT-SO-NEXT:       Access: -32752
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:       Purpose: Lazy resolver
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108E4
+GOT-SO-NEXT:       Access: -32748
+GOT-SO-NEXT:       Initial: 0x80000000
+GOT-SO-NEXT:       Purpose: Module pointer (GNU extension)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:   ]
+GOT-SO-NEXT:   Local entries [
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108E8
+GOT-SO-NEXT:       Access: -32744
+GOT-SO-NEXT:       Initial: 0x108E0
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108EC
+GOT-SO-NEXT:       Access: -32740
+GOT-SO-NEXT:       Initial: 0x10000
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108F0
+GOT-SO-NEXT:       Access: -32736
+GOT-SO-NEXT:       Initial: 0x10920
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108F4
+GOT-SO-NEXT:       Access: -32732
+GOT-SO-NEXT:       Initial: 0x108CC
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108F8
+GOT-SO-NEXT:       Access: -32728
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x108FC
+GOT-SO-NEXT:       Access: -32724
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x10900
+GOT-SO-NEXT:       Access: -32720
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x10904
+GOT-SO-NEXT:       Access: -32716
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:   ]
+GOT-SO-NEXT:   Global entries [
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x10908
+GOT-SO-NEXT:       Access: -32712
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:       Value: 0x0
+GOT-SO-NEXT:       Type: None (0x0)
+GOT-SO-NEXT:       Section: Undefined (0x0)
+GOT-SO-NEXT:       Name: _ITM_registerTMCloneTable@ (87)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x1090C
+GOT-SO-NEXT:       Access: -32708
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:       Value: 0x0
+GOT-SO-NEXT:       Type: None (0x0)
+GOT-SO-NEXT:       Section: Undefined (0x0)
+GOT-SO-NEXT:       Name: _Jv_RegisterClasses@ (128)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x10910
+GOT-SO-NEXT:       Access: -32704
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:       Value: 0x0
+GOT-SO-NEXT:       Type: Function (0x2)
+GOT-SO-NEXT:       Section: Undefined (0x0)
+GOT-SO-NEXT:       Name: __gmon_start__@ (23)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x10914
+GOT-SO-NEXT:       Access: -32700
+GOT-SO-NEXT:       Initial: 0x840
+GOT-SO-NEXT:       Value: 0x840
+GOT-SO-NEXT:       Type: Function (0x2)
+GOT-SO-NEXT:       Section: Undefined (0x0)
+GOT-SO-NEXT:       Name: puts@GLIBC_2.0 (162)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x10918
+GOT-SO-NEXT:       Access: -32696
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:       Value: 0x0
+GOT-SO-NEXT:       Type: None (0x0)
+GOT-SO-NEXT:       Section: Undefined (0x0)
+GOT-SO-NEXT:       Name: _ITM_deregisterTMCloneTable@ (59)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:     Entry {
+GOT-SO-NEXT:       Address: 0x1091C
+GOT-SO-NEXT:       Access: -32692
+GOT-SO-NEXT:       Initial: 0x0
+GOT-SO-NEXT:       Value: 0x0
+GOT-SO-NEXT:       Type: Function (0x2)
+GOT-SO-NEXT:       Section: Undefined (0x0)
+GOT-SO-NEXT:       Name: __cxa_finalize@GLIBC_2.2 (113)
+GOT-SO-NEXT:     }
+GOT-SO-NEXT:   ]
+GOT-SO-NEXT:   Number of TLS and multi-GOT entries: 0
+GOT-SO-NEXT: }
+
+GOT-TLS:      Primary GOT {
+GOT-TLS-NEXT:   Canonical gp value: 0x18BF0
+GOT-TLS-NEXT:   Reserved entries [
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C00
+GOT-TLS-NEXT:       Access: -32752
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:       Purpose: Lazy resolver
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C08
+GOT-TLS-NEXT:       Access: -32744
+GOT-TLS-NEXT:       Initial: 0x8000000000000000
+GOT-TLS-NEXT:       Purpose: Module pointer (GNU extension)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:   ]
+GOT-TLS-NEXT:   Local entries [
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C10
+GOT-TLS-NEXT:       Access: -32736
+GOT-TLS-NEXT:       Initial: 0x10000
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C18
+GOT-TLS-NEXT:       Access: -32728
+GOT-TLS-NEXT:       Initial: 0x10C00
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C20
+GOT-TLS-NEXT:       Access: -32720
+GOT-TLS-NEXT:       Initial: 0x10CB8
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C28
+GOT-TLS-NEXT:       Access: -32712
+GOT-TLS-NEXT:       Initial: 0x10BF0
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C30
+GOT-TLS-NEXT:       Access: -32704
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C38
+GOT-TLS-NEXT:       Access: -32696
+GOT-TLS-NEXT:       Initial: 0x948
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C40
+GOT-TLS-NEXT:       Access: -32688
+GOT-TLS-NEXT:       Initial: 0xA20
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C48
+GOT-TLS-NEXT:       Access: -32680
+GOT-TLS-NEXT:       Initial: 0xAF0
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C50
+GOT-TLS-NEXT:       Access: -32672
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C58
+GOT-TLS-NEXT:       Access: -32664
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C60
+GOT-TLS-NEXT:       Access: -32656
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:   ]
+GOT-TLS-NEXT:   Global entries [
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C68
+GOT-TLS-NEXT:       Access: -32648
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:       Value: 0x0
+GOT-TLS-NEXT:       Type: None (0x0)
+GOT-TLS-NEXT:       Section: Undefined (0x0)
+GOT-TLS-NEXT:       Name: _ITM_registerTMCloneTable@ (78)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C70
+GOT-TLS-NEXT:       Access: -32640
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:       Value: 0x0
+GOT-TLS-NEXT:       Type: None (0x0)
+GOT-TLS-NEXT:       Section: Undefined (0x0)
+GOT-TLS-NEXT:       Name: _Jv_RegisterClasses@ (119)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C78
+GOT-TLS-NEXT:       Access: -32632
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:       Value: 0x0
+GOT-TLS-NEXT:       Type: Function (0x2)
+GOT-TLS-NEXT:       Section: Undefined (0x0)
+GOT-TLS-NEXT:       Name: __gmon_start__@ (23)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C80
+GOT-TLS-NEXT:       Access: -32624
+GOT-TLS-NEXT:       Initial: 0xB60
+GOT-TLS-NEXT:       Value: 0xB60
+GOT-TLS-NEXT:       Type: Function (0x2)
+GOT-TLS-NEXT:       Section: Undefined (0x0)
+GOT-TLS-NEXT:       Name: __tls_get_addr@GLIBC_2.3 (150)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C88
+GOT-TLS-NEXT:       Access: -32616
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:       Value: 0x0
+GOT-TLS-NEXT:       Type: None (0x0)
+GOT-TLS-NEXT:       Section: Undefined (0x0)
+GOT-TLS-NEXT:       Name: _ITM_deregisterTMCloneTable@ (50)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:     Entry {
+GOT-TLS-NEXT:       Address: 0x10C90
+GOT-TLS-NEXT:       Access: -32608
+GOT-TLS-NEXT:       Initial: 0x0
+GOT-TLS-NEXT:       Value: 0x0
+GOT-TLS-NEXT:       Type: Function (0x2)
+GOT-TLS-NEXT:       Section: Undefined (0x0)
+GOT-TLS-NEXT:       Name: __cxa_finalize@GLIBC_2.2 (104)
+GOT-TLS-NEXT:     }
+GOT-TLS-NEXT:   ]
+GOT-TLS-NEXT:   Number of TLS and multi-GOT entries: 4
+GOT-TLS-NEXT: }

tools/llvm-readobj/ELFDumper.cpp

 //===----------------------------------------------------------------------===//
 
 #include "llvm-readobj.h"
 #include "ARMAttributeParser.h"
 #include "ARMEHABIPrinter.h"
 #include "Error.h"
 #include "ObjDumper.h"
 #include "StreamWriter.h"
+#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Object/ELFObjectFile.h"
 #include "llvm/Support/ARMBuildAttributes.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Format.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/raw_ostream.h"
public:
   void printDynamicSymbols() override;
   void printUnwindInfo() override;
 
   void printDynamicTable() override;
   void printNeededLibraries() override;
   void printProgramHeaders() override;
 
   void printAttributes() override;
+  void printMipsPLTGOT() override;
 
 private:
   typedef ELFFile<ELFT> ELFO;
   typedef typename ELFO::Elf_Shdr Elf_Shdr;
   typedef typename ELFO::Elf_Sym Elf_Sym;
 
   void printSymbol(typename ELFO::Elf_Sym_Iter Symbol);
 
   void printRelocations(const Elf_Shdr *Sec);
   void printRelocation(const Elf_Shdr *Sec, typename ELFO::Elf_Rela Rel);
 
   const ELFO *Obj;
 };
 
 template <class T> T errorOrDefault(ErrorOr<T> Val, T Default = T()) {
   if (!Val) {
     error(Val.getError());
     return Default;
   }
 
   return *Val;
 }
 } // namespace
 
 namespace llvm {
 
 template <class ELFT>
 static error_code createELFDumper(const ELFFile<ELFT> *Obj,
                                   StreamWriter &Writer,
                                   std::unique_ptr<ObjDumper> &Result) {
   Result.reset(new ELFDumper<ELFT>(Obj, Writer));
   return readobj_error::success;
 }
if (SectionIndex == SHN_XINDEX)
       SectionIndex = Obj.getSymbolTableIndex(&*Symbol);
     assert(SectionIndex != SHN_XINDEX &&
            "getSymbolTableIndex should handle this");
     const typename ELFO::Elf_Shdr *Sec = Obj.getSection(SectionIndex);
     SectionName = errorOrDefault(Obj.getSectionName(Sec));
   }
 }
 
+template <class ELFT>
+static const typename ELFFile<ELFT>::Elf_Shdr *
+findSectionByAddress(const ELFFile<ELFT> *Obj, uint64_t Addr) {
+  for (const auto &Shdr : Obj->sections())
+    if (Shdr.sh_addr == Addr)
+      return &Shdr;
+  return nullptr;
+}
+
 static const EnumEntry<unsigned> ElfClass[] = {
   { "None",   ELF::ELFCLASSNONE },
   { "32-bit", ELF::ELFCLASS32   },
   { "64-bit", ELF::ELFCLASS64   },
 };
 
 static const EnumEntry<unsigned> ElfDataEncoding[] = {
   { "None",         ELF::ELFDATANONE },
OS << W.hex(Rel.r_offset)
        << " " << RelocName
        << " " << (SymbolName.size() > 0 ? SymbolName : "-")
        << " " << W.hex(Rel.r_addend)
        << "\n";
   }
 }
 
 template<class ELFT>
 void ELFDumper<ELFT>::printSymbols() {
   ListScope Group(W, "Symbols");
   for (typename ELFO::Elf_Sym_Iter SymI = Obj->begin_symbols(),
                                    SymE = Obj->end_symbols();
        SymI != SymE; ++SymI) {
     printSymbol(SymI);
   }
 }
 
 template<class ELFT>
 void ELFDumper<ELFT>::printDynamicSymbols() {
   ListScope Group(W, "DynamicSymbols");
 
   for (typename ELFO::Elf_Sym_Iter SymI = Obj->begin_dynamic_symbols(),
                                    SymE = Obj->end_dynamic_symbols();
        SymI != SymE; ++SymI) {
     printSymbol(SymI);
   }
 }
 
 template <class ELFT>
 void ELFDumper<ELFT>::printSymbol(typename ELFO::Elf_Sym_Iter Symbol) {
   unsigned SectionIndex = 0;
   StringRef SectionName;
   getSectionNameIndex(*Obj, Symbol, SectionName, SectionIndex);
   std::string FullSymbolName = getFullSymbolName(*Obj, Symbol);
 
   DictScope D(W, "Symbol");
   W.printNumber("Name", FullSymbolName, Symbol->st_name);
   W.printHex   ("Value", Symbol->st_value);
   W.printNumber("Size", Symbol->st_size);
   W.printEnum  ("Binding", Symbol->getBinding(),
                   makeArrayRef(ElfSymbolBindings));
for (ELFO::Elf_Shdr_Iter SI = Obj->begin_sections(), SE = Obj->end_sections();
     if (Contents->size() == 1)
       continue;
 
     ARMAttributeParser(W).Parse(*Contents);
   }
 }
 }
 
+namespace {
+template <class ELFT> class MipsGOTParser {
+public:
+  typedef object::ELFFile<ELFT> ObjectFile;
+  typedef typename ObjectFile::Elf_Shdr Elf_Shdr;
+
+  MipsGOTParser(const ObjectFile *Obj, StreamWriter &W) : Obj(Obj), W(W) {}
+
+  void ParseGOT(const Elf_Shdr &GOTShdr);
+
+private:
+  typedef typename ObjectFile::Elf_Sym_Iter Elf_Sym_Iter;
+  typedef typename ObjectFile::Elf_Addr GOTEntry;
+  typedef typename ObjectFile::template ELFEntityIterator<const GOTEntry>
+  GOTIter;
+
+  const ObjectFile *Obj;
+  StreamWriter &W;
+
+  std::size_t GetGOTTotal(ArrayRef<uint8_t> GOT) const;
+  GOTIter MakeGOTIter(ArrayRef<uint8_t> GOT, std::size_t EntryNum);
+
+  bool GetGOTTags(uint64_t &LocalGotNum, uint64_t &GotSym);
+  void printGotEntry(uint64_t GotAddr, GOTIter BeginIt, GOTIter It);
+  void printGlobalGotEntry(uint64_t GotAddr, GOTIter BeginIt, GOTIter It,
+                           Elf_Sym_Iter Sym);
+};
+}
+
+template <class ELFT>
+void MipsGOTParser<ELFT>::ParseGOT(const Elf_Shdr &GOTShdr) {
+  ErrorOr<ArrayRef<uint8_t>> GOT = Obj->getSectionContents(&GOTShdr);
+  if (!GOT) {
+    W.startLine() << "The .got section is empty.\n";
+    return;
+  }
+
+  uint64_t DtLocalGotNum;
+  uint64_t DtGotSym;
+  if (!GetGOTTags(DtLocalGotNum, DtGotSym))
+    return;
+
+  if (DtLocalGotNum > GetGOTTotal(*GOT)) {
+    W.startLine() << "MIPS_LOCAL_GOTNO exceeds a number of GOT entries.\n";
+    return;
+  }
+
+  Elf_Sym_Iter DynSymBegin = Obj->begin_dynamic_symbols();
+  Elf_Sym_Iter DynSymEnd = Obj->end_dynamic_symbols();
+  std::size_t DynSymTotal = std::size_t(std::distance(DynSymBegin, DynSymEnd));
+
+  if (DtGotSym + 1 > DynSymTotal) {
+    W.startLine() << "MIPS_GOTSYM exceeds a number of dynamic symbols.\n";
+    return;
+  }
+
+  std::size_t GlobalGotNum = DynSymTotal - DtGotSym;
+
+  if (DtLocalGotNum + GlobalGotNum > GetGOTTotal(*GOT)) {
+    W.startLine() << "Number of global GOT entries exceeds the size of GOT.\n";
+    return;
+  }
+
+  GOTIter GotBegin = MakeGOTIter(*GOT, 0);
+  GOTIter GotLocalEnd = MakeGOTIter(*GOT, DtLocalGotNum);
+  GOTIter It = GotBegin;
+
+  DictScope GS(W, "Primary GOT");
+
+  W.printHex("Canonical gp value", GOTShdr.sh_addr + 0x7ff0);
+  {
+    ListScope RS(W, "Reserved entries");
+
+    {
+      DictScope D(W, "Entry");
+      printGotEntry(GOTShdr.sh_addr, GotBegin, It++);
+      W.printString("Purpose", StringRef("Lazy resolver"));
+    }
+
+    if (It != GotLocalEnd && (*It >> (sizeof(GOTEntry) * 8 - 1)) != 0) {
+      DictScope D(W, "Entry");
+      printGotEntry(GOTShdr.sh_addr, GotBegin, It++);
+      W.printString("Purpose", StringRef("Module pointer (GNU extension)"));
+    }
+  }
+  {
+    ListScope LS(W, "Local entries");
+    for (; It != GotLocalEnd; ++It) {
+      DictScope D(W, "Entry");
+      printGotEntry(GOTShdr.sh_addr, GotBegin, It);
+    }
+  }
+  {
+    ListScope GS(W, "Global entries");
+
+    GOTIter GotGlobalEnd = MakeGOTIter(*GOT, DtLocalGotNum + GlobalGotNum);
+    Elf_Sym_Iter GotDynSym = DynSymBegin + DtGotSym;
+    for (; It != GotGlobalEnd; ++It) {
+      DictScope D(W, "Entry");
+      printGlobalGotEntry(GOTShdr.sh_addr, GotBegin, It, GotDynSym++);
+    }
+  }
+
+  std::size_t SpecGotNum = GetGOTTotal(*GOT) - DtLocalGotNum - GlobalGotNum;
+  W.printNumber("Number of TLS and multi-GOT entries", SpecGotNum);
+}
+
+template <class ELFT>
+std::size_t MipsGOTParser<ELFT>::GetGOTTotal(ArrayRef<uint8_t> GOT) const {
+  return GOT.size() / sizeof(GOTEntry);
+}
+
+template <class ELFT>
+typename MipsGOTParser<ELFT>::GOTIter
+MipsGOTParser<ELFT>::MakeGOTIter(ArrayRef<uint8_t> GOT, std::size_t EntryNum) {
+  const char *Data = reinterpret_cast<const char *>(GOT.data());
+  return GOTIter(sizeof(GOTEntry), Data + EntryNum * sizeof(GOTEntry));
+}
+
+template <class ELFT>
+bool MipsGOTParser<ELFT>::GetGOTTags(uint64_t &LocalGotNum, uint64_t &GotSym) {
+  bool FoundLocalGotNum = false;
+  bool FoundGotSym = false;
+  for (const auto &Entry : Obj->dynamic_table()) {
+    switch (Entry.getTag()) {
+    case ELF::DT_MIPS_LOCAL_GOTNO:
+      LocalGotNum = Entry.getVal();
+      FoundLocalGotNum = true;
+      break;
+    case ELF::DT_MIPS_GOTSYM:
+      GotSym = Entry.getVal();
+      FoundGotSym = true;
+      break;
+    }
+  }
+
+  if (!FoundLocalGotNum) {
+    W.startLine() << "Cannot find MIPS_LOCAL_GOTNO dynamic table tag.\n";
+    return false;
+  }
+
+  if (!FoundGotSym) {
+    W.startLine() << "Cannot find MIPS_GOTSYM dynamic table tag.\n";
+    return false;
+  }
+
+  return true;
+}
+
+template <class ELFT>
+void MipsGOTParser<ELFT>::printGotEntry(uint64_t GotAddr, GOTIter BeginIt,
+                                        GOTIter It) {
+  int64_t Offset = std::distance(BeginIt, It) * sizeof(GOTEntry);
+  W.printHex("Address", GotAddr + Offset);
+  W.printNumber("Access", Offset - 0x7ff0);
+  W.printHex("Initial", *It);
+}
+
+template <class ELFT>
+void MipsGOTParser<ELFT>::printGlobalGotEntry(uint64_t GotAddr, GOTIter BeginIt,
+                                              GOTIter It, Elf_Sym_Iter Sym) {
+  printGotEntry(GotAddr, BeginIt, It);
+
+  W.printHex("Value", Sym->st_value);
+  W.printEnum("Type", Sym->getType(), makeArrayRef(ElfSymbolTypes));
+
+  unsigned SectionIndex = 0;
+  StringRef SectionName;
+  getSectionNameIndex(*Obj, Sym, SectionName, SectionIndex);
+  W.printHex("Section", SectionName, SectionIndex);
+
+  std::string FullSymbolName = getFullSymbolName(*Obj, Sym);
+  W.printNumber("Name", FullSymbolName, Sym->st_name);
+}
+
+template <class ELFT> void ELFDumper<ELFT>::printMipsPLTGOT() {
+  if (Obj->getHeader()->e_machine != EM_MIPS) {
+    W.startLine() << "MIPS PLT GOT is available for MIPS targets only.\n";
+    return;
+  }
+
+  llvm::Optional<uint64_t> DtPltGot;
+  for (const auto &Entry : Obj->dynamic_table()) {
+    if (Entry.getTag() == ELF::DT_PLTGOT) {
+      DtPltGot = Entry.getVal();
+      break;
+    }
+  }
+
+  if (!DtPltGot) {
+    W.startLine() << "Cannot find PLTGOT dynamic table tag.\n";
+    return;
+  }
+
+  const Elf_Shdr *GotShdr = findSectionByAddress(Obj, *DtPltGot);
+  if (!GotShdr) {
+    W.startLine() << "There is no .got section in the file.\n";
+    return;
+  }
+
+  MipsGOTParser<ELFT>(Obj, W).ParseGOT(*GotShdr);
+}

tools/llvm-readobj/ObjDumper.h

public:
   // Only implemented for ELF at this time.
   virtual void printDynamicTable() { }
   virtual void printNeededLibraries() { }
   virtual void printProgramHeaders() { }
 
   // Only implemented for ARM ELF at this time.
   virtual void printAttributes() { }
 
+  // Only implemented for MIPS ELF at this time.
+  virtual void printMipsPLTGOT() { }
+
 protected:
   StreamWriter& W;
 };
 
 error_code createCOFFDumper(const object::ObjectFile *Obj, StreamWriter &Writer,
                             std::unique_ptr<ObjDumper> &Result);
 
 error_code createELFDumper(const object::ObjectFile *Obj, StreamWriter &Writer,

tools/llvm-readobj/llvm-readobj.h

namespace opts {
   extern llvm::cl::opt<bool> SectionData;
   extern llvm::cl::opt<bool> Relocations;
   extern llvm::cl::opt<bool> Symbols;
   extern llvm::cl::opt<bool> DynamicSymbols;
   extern llvm::cl::opt<bool> UnwindInfo;
   extern llvm::cl::opt<bool> ExpandRelocs;
   extern llvm::cl::opt<bool> CodeViewLineTables;
   extern llvm::cl::opt<bool> ARMAttributes;
+  extern llvm::cl::opt<bool> MipsPLTGOT;
 } // namespace opts
 
 #define LLVM_READOBJ_ENUM_ENT(ns, enum) \
   { #enum, ns::enum }
 
 #endif

tools/llvm-readobj/llvm-readobj.cpp

namespace opts {
   cl::opt<bool> CodeViewLineTables("codeview-linetables",
     cl::desc("Display CodeView line table information"));
 
   // -arm-attributes, -a
   cl::opt<bool> ARMAttributes("arm-attributes",
                               cl::desc("Display the ARM attributes section"));
   cl::alias ARMAttributesShort("-a", cl::desc("Alias for --arm-attributes"),
                                cl::aliasopt(ARMAttributes));
+
+  // -mips-plt-got
+  cl::opt<bool>
+  MipsPLTGOT("mips-plt-got",
+             cl::desc("Display the MIPS GOT and PLT GOT sections"));
 } // namespace opts
 
 static int ReturnValue = EXIT_SUCCESS;
 
 namespace llvm {
 
 bool error(error_code EC) {
   if (!EC)

 static void reportError(StringRef Input, StringRef Message) {
   if (Input == "-")
     Input = "<stdin>";
 
   errs() << Input << ": " << Message << "\n";
   ReturnValue = EXIT_FAILURE;
 }
 
+static bool isMipsArch(unsigned Arch) {
+  switch (Arch) {
+  case llvm::Triple::mips:
+  case llvm::Triple::mipsel:
+  case llvm::Triple::mips64:
+  case llvm::Triple::mips64el:
+    return true;
+  default:
+    return false;
+  }
+}
+
 /// @brief Creates an format-specific object file dumper.
 static error_code createDumper(const ObjectFile *Obj, StreamWriter &Writer,
                                std::unique_ptr<ObjDumper> &Result) {
   if (!Obj)
     return readobj_error::unsupported_file_format;
 
   if (Obj->isCOFF())
     return createCOFFDumper(Obj, Writer, Result);
if (opts::DynamicTable)
     Dumper->printDynamicTable();
   if (opts::NeededLibraries)
     Dumper->printNeededLibraries();
   if (opts::ProgramHeaders)
     Dumper->printProgramHeaders();
   if (Obj->getArch() == llvm::Triple::arm && Obj->isELF())
     if (opts::ARMAttributes)
       Dumper->printAttributes();
+  if (isMipsArch(Obj->getArch()) && Obj->isELF())
+    if (opts::MipsPLTGOT)
+      Dumper->printMipsPLTGOT();
 }
 
 
 /// @brief Dumps each object file in \a Arc;
 static void dumpArchive(const Archive *Arc) {
   for (Archive::child_iterator ArcI = Arc->child_begin(),
                                ArcE = Arc->child_end();
                                ArcI != ArcE; ++ArcI) {