[llvm-readobj/ELF] Print GNU Hash section

Add a new command line switch, -gnu-hash-table, to print the content of that section.

Differential Revision: http://reviews.llvm.org/D13696

llvm-svn: 250291

1 files changed, 24 insertions, 0 deletions

diff --git a/llvm/tools/llvm-readobj/ELFDumper.cpp b/llvm/tools/llvm-readobj/ELFDumper.cpp
index b39d56667c1..2f07f47919e 100644
--- a/llvm/tools/llvm-readobj/ELFDumper.cpp
+++ b/llvm/tools/llvm-readobj/ELFDumper.cpp
@@ -56,6 +56,7 @@ public:
   void printNeededLibraries() override;
   void printProgramHeaders() override;
   void printHashTable() override;
+  void printGnuHashTable() override;
   void printLoadName() override;
 
   void printAttributes() override;
@@ -76,6 +77,7 @@ private:
   typedef typename ELFO::Elf_Rela_Range Elf_Rela_Range;
   typedef typename ELFO::Elf_Phdr Elf_Phdr;
   typedef typename ELFO::Elf_Hash Elf_Hash;
+  typedef typename ELFO::Elf_GnuHash Elf_GnuHash;
   typedef typename ELFO::Elf_Ehdr Elf_Ehdr;
   typedef typename ELFO::Elf_Word Elf_Word;
   typedef typename ELFO::uintX_t uintX_t;
@@ -136,6 +138,7 @@ private:
   const Elf_Sym *DynSymStart = nullptr;
   StringRef SOName;
   const Elf_Hash *HashTable = nullptr;
+  const Elf_GnuHash *GnuHashTable = nullptr;
   const Elf_Shdr *DotDynSymSec = nullptr;
   const Elf_Shdr *DotSymtabSec = nullptr;
   ArrayRef<Elf_Word> ShndxTable;
@@ -850,6 +853,10 @@ ELFDumper<ELFT>::ELFDumper(const ELFFile<ELFT> *Obj, StreamWriter &Writer)
       HashTable =
           reinterpret_cast<const Elf_Hash *>(toMappedAddr(Dyn.getPtr()));
       break;
+    case ELF::DT_GNU_HASH:
+      GnuHashTable =
+          reinterpret_cast<const Elf_GnuHash *>(toMappedAddr(Dyn.getPtr()));
+      break;
     case ELF::DT_RELA:
       DynRelaRegion.Addr = toMappedAddr(Dyn.getPtr());
       break;
@@ -1533,6 +1540,23 @@ void ELFDumper<ELFT>::printHashTable() {
   W.printList("Chains", HashTable->chains());
 }
 
+template <typename ELFT>
+void ELFDumper<ELFT>::printGnuHashTable() {
+  DictScope D(W, "GnuHashTable");
+  if (!GnuHashTable)
+    return;
+  W.printNumber("Num Buckets", GnuHashTable->nbuckets);
+  W.printNumber("First Hashed Symbol Index", GnuHashTable->symndx);
+  W.printNumber("Num Mask Words", GnuHashTable->maskwords);
+  W.printNumber("Shift Count", GnuHashTable->shift2);
+  W.printHexList("Bloom Filter", GnuHashTable->filter());
+  W.printList("Buckets", GnuHashTable->buckets());
+  if (!DotDynSymSec)
+    reportError("No dynamic symbol section");
+  W.printHexList("Values",
+                 GnuHashTable->values(DotDynSymSec->getEntityCount()));
+}
+
 template <typename ELFT> void ELFDumper<ELFT>::printLoadName() {
   outs() << "LoadName: " << SOName << '\n';
 }