[Object][ELF] Add support for dumping dynamic relocations when sections are stripped.

llvm-svn: 240703

3 files changed, 44 insertions, 3 deletions

diff --git a/llvm/tools/llvm-readobj/ELFDumper.cpp b/llvm/tools/llvm-readobj/ELFDumper.cpp
index d8c089a63e3..3df8ed9f710 100644
--- a/llvm/tools/llvm-readobj/ELFDumper.cpp
+++ b/llvm/tools/llvm-readobj/ELFDumper.cpp
@@ -47,6 +47,7 @@ public:
   void printFileHeaders() override;
   void printSections() override;
   void printRelocations() override;
+  void printDynamicRelocations() override;
   void printSymbols() override;
   void printDynamicSymbols() override;
   void printUnwindInfo() override;
@@ -676,6 +677,39 @@ void ELFDumper<ELFT>::printRelocations() {
   }
 }
 
+template<class ELFT>
+void ELFDumper<ELFT>::printDynamicRelocations() {
+  W.startLine() << "Dynamic Relocations {\n";
+  W.indent();
+  for (typename ELFO::Elf_Rela_Iter RelI = Obj->begin_dyn_rela(),
+    RelE = Obj->end_dyn_rela();
+    RelI != RelE; ++RelI) {
+    SmallString<32> RelocName;
+    Obj->getRelocationTypeName(RelI->getType(Obj->isMips64EL()), RelocName);
+    StringRef SymbolName;
+    uint32_t SymIndex = RelI->getSymbol(Obj->isMips64EL());
+    typename ELFO::Elf_Sym_Iter Sym = Obj->begin_dynamic_symbols() + SymIndex;
+    SymbolName = errorOrDefault(Obj->getSymbolName(Sym));
+    if (opts::ExpandRelocs) {
+      DictScope Group(W, "Relocation");
+      W.printHex("Offset", RelI->r_offset);
+      W.printNumber("Type", RelocName, (int)RelI->getType(Obj->isMips64EL()));
+      W.printString("Symbol", SymbolName.size() > 0 ? SymbolName : "-");
+      W.printHex("Addend", RelI->r_addend);
+    }
+    else {
+      raw_ostream& OS = W.startLine();
+      OS << W.hex(RelI->r_offset)
+        << " " << RelocName
+        << " " << (SymbolName.size() > 0 ? SymbolName : "-")
+        << " " << W.hex(RelI->r_addend)
+        << "\n";
+    }
+  }
+  W.unindent();
+  W.startLine() << "}\n";
+}
+
 template <class ELFT>
 void ELFDumper<ELFT>::printRelocations(const Elf_Shdr *Sec) {
   switch (Sec->sh_type) {
@@ -986,6 +1020,9 @@ static void printValue(const ELFFile<ELFT> *O, uint64_t Type, uint64_t Value,
   case DT_FLAGS_1:
     printFlags(Value, makeArrayRef(ElfDynamicDTFlags1), OS);
     break;
+  default:
+    OS << format("0x%" PRIX64, Value);
+    break;
   }
 }
 
diff --git a/llvm/tools/llvm-readobj/ObjDumper.h b/llvm/tools/llvm-readobj/ObjDumper.h
index 323f5e319cf..cfca850150f 100644
--- a/llvm/tools/llvm-readobj/ObjDumper.h
+++ b/llvm/tools/llvm-readobj/ObjDumper.h
@@ -33,6 +33,7 @@ public:
   virtual void printUnwindInfo() = 0;
 
   // Only implemented for ELF at this time.
+  virtual void printDynamicRelocations() { }
   virtual void printDynamicTable() { }
   virtual void printNeededLibraries() { }
   virtual void printProgramHeaders() { }
diff --git a/llvm/tools/llvm-readobj/llvm-readobj.cpp b/llvm/tools/llvm-readobj/llvm-readobj.cpp
index d40cc05d0f4..3a6483a1386 100644
--- a/llvm/tools/llvm-readobj/llvm-readobj.cpp
+++ b/llvm/tools/llvm-readobj/llvm-readobj.cpp
@@ -40,7 +40,6 @@
 #include <string>
 #include <system_error>
 
-
 using namespace llvm;
 using namespace llvm::object;
 
@@ -91,6 +90,10 @@ namespace opts {
     cl::desc("Alias for --relocations"),
     cl::aliasopt(Relocations));
 
+  // -dyn-relocations
+  cl::opt<bool> DynRelocs("dyn-relocations",
+    cl::desc("Display the dynamic relocation entries in the file"));
+
   // -symbols, -t
   cl::opt<bool> Symbols("symbols",
     cl::desc("Display the symbol table"));
@@ -280,6 +283,8 @@ static void dumpObject(const ObjectFile *Obj) {
     Dumper->printSections();
   if (opts::Relocations)
     Dumper->printRelocations();
+  if (opts::DynRelocs)
+    Dumper->printDynamicRelocations();
   if (opts::Symbols)
     Dumper->printSymbols();
   if (opts::DynamicSymbols)
@@ -313,7 +318,6 @@ static void dumpObject(const ObjectFile *Obj) {
     Dumper->printCOFFBaseReloc();
 }
 
-
 /// @brief Dumps each object file in \a Arc;
 static void dumpArchive(const Archive *Arc) {
   for (Archive::child_iterator ArcI = Arc->child_begin(),
@@ -374,7 +378,6 @@ static void dumpInput(StringRef File) {
     reportError(File, readobj_error::unrecognized_file_format);
 }
 
-
 int main(int argc, const char *argv[]) {
   sys::PrintStackTraceOnErrorSignal();
   PrettyStackTraceProgram X(argc, argv);