[dwarfdump] Add support for dumping mach-o universal objectfiles

llvm-svn: 243862
diff --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
index 018e666..f641c6b 100644
--- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
+++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
@@ -15,6 +15,7 @@
 #include "llvm/ADT/Triple.h"
 #include "llvm/DebugInfo/DIContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/Object/MachOUniversal.h"
 #include "llvm/Object/ObjectFile.h"
 #include "llvm/Object/RelocVisitor.h"
 #include "llvm/Support/CommandLine.h"
@@ -76,11 +77,11 @@
   exit(1);
 }
 
-static void DumpObjectFile(ObjectFile &Obj, StringRef Filename) {
+static void DumpObjectFile(ObjectFile &Obj, Twine Filename) {
   std::unique_ptr<DIContext> DICtx(new DWARFContextInMemory(Obj));
 
-  outs() << Filename
-         << ":\tfile format " << Obj.getFileFormatName() << "\n\n";
+  outs() << Filename.str() << ":\tfile format " << Obj.getFileFormatName()
+         << "\n\n";
   // Dump the complete DWARF structure.
   DICtx->dump(outs(), DumpType);
 }
@@ -91,12 +92,19 @@
   error(Filename, BuffOrErr.getError());
   std::unique_ptr<MemoryBuffer> Buff = std::move(BuffOrErr.get());
 
-  ErrorOr<std::unique_ptr<ObjectFile>> ObjOrErr =
-      ObjectFile::createObjectFile(Buff->getMemBufferRef());
-  error(Filename, ObjOrErr.getError());
-  ObjectFile &Obj = *ObjOrErr.get();
+  ErrorOr<std::unique_ptr<Binary>> BinOrErr =
+      object::createBinary(Buff->getMemBufferRef());
+  error(Filename, BinOrErr.getError());
 
-  DumpObjectFile(Obj, Filename);
+  if (auto *Obj = dyn_cast<ObjectFile>(BinOrErr->get()))
+    DumpObjectFile(*Obj, Filename);
+  else if (auto *Fat = dyn_cast<MachOUniversalBinary>(BinOrErr->get()))
+    for (auto &ObjForArch : Fat->objects()) {
+      auto MachOOrErr = ObjForArch.getAsObjectFile();
+      error(Filename, MachOOrErr.getError());
+      DumpObjectFile(**MachOOrErr,
+                     Filename + " (" + ObjForArch.getArchTypeName() + ")");
+    }
 }
 
 int main(int argc, char **argv) {