1 files changed, 66 insertions, 1 deletions

diff --git a/llvm/tools/llvm-objdump/MachODump.cpp b/llvm/tools/llvm-objdump/MachODump.cpp
index 67aa6a3c1ad..e103842e54f 100644
--- a/llvm/tools/llvm-objdump/MachODump.cpp
+++ b/llvm/tools/llvm-objdump/MachODump.cpp
@@ -36,6 +36,7 @@
 #include "llvm/Support/Format.h"
 #include "llvm/Support/FormattedStream.h"
 #include "llvm/Support/GraphWriter.h"
+#include "llvm/Support/LEB128.h"
 #include "llvm/Support/MachO.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/TargetRegistry.h"
@@ -85,6 +86,11 @@ cl::opt<bool>
                      cl::desc("Print the data in code table for Mach-O objects "
                               "(requires -macho)"));
 
+cl::opt<bool>
+    llvm::LinkOptHints("link-opt-hints",
+                       cl::desc("Print the linker optimization hints for "
+                                "Mach-O objects (requires -macho)"));
+
 static cl::list<std::string>
     ArchFlags("arch", cl::desc("architecture(s) from a Mach-O file to dump"),
               cl::ZeroOrMore);
@@ -436,6 +442,63 @@ static void PrintDataInCodeTable(MachOObjectFile *O, bool verbose) {
   }
 }
 
+static void PrintLinkOptHints(MachOObjectFile *O) {
+  MachO::linkedit_data_command LohLC = O->getLinkOptHintsLoadCommand();
+  const char *loh = O->getData().substr(LohLC.dataoff, 1).data();
+  uint32_t nloh = LohLC.datasize;
+  outs() << "Linker optimiztion hints (" << nloh << " total bytes)\n";
+  for (uint32_t i = 0; i < nloh;) {
+    unsigned n;
+    uint64_t identifier = decodeULEB128((const uint8_t *)(loh + i), &n);
+    i += n;
+    outs() << "    identifier " << identifier << " ";
+    if (i >= nloh)
+      return;
+    switch (identifier) {
+    case 1:
+      outs() << "AdrpAdrp\n";
+      break;
+    case 2:
+      outs() << "AdrpLdr\n";
+      break;
+    case 3:
+      outs() << "AdrpAddLdr\n";
+      break;
+    case 4:
+      outs() << "AdrpLdrGotLdr\n";
+      break;
+    case 5:
+      outs() << "AdrpAddStr\n";
+      break;
+    case 6:
+      outs() << "AdrpLdrGotStr\n";
+      break;
+    case 7:
+      outs() << "AdrpAdd\n";
+      break;
+    case 8:
+      outs() << "AdrpLdrGot\n";
+      break;
+    default:
+      outs() << "Unknown identifier value\n";
+      break;
+    }
+    uint64_t narguments = decodeULEB128((const uint8_t *)(loh + i), &n);
+    i += n;
+    outs() << "    narguments " << narguments << "\n";
+    if (i >= nloh)
+      return;
+
+    for (uint32_t j = 0; j < narguments; j++) {
+      uint64_t value = decodeULEB128((const uint8_t *)(loh + i), &n);
+      i += n;
+      outs() << "\tvalue " << format("0x%" PRIx64, value) << "\n";
+      if (i >= nloh)
+        return;
+    }
+  }
+}
+
 // checkMachOAndArchFlags() checks to see if the ObjectFile is a Mach-O file
 // and if it is and there is a list of architecture flags is specified then
 // check to make sure this Mach-O file is one of those architectures or all
@@ -483,7 +546,7 @@ static void ProcessMachO(StringRef Filename, MachOObjectFile *MachOOF,
   // info.  And don't print it otherwise like in the case of printing the
   // UniversalHeaders or ArchiveHeaders.
   if (Disassemble || PrivateHeaders || ExportsTrie || Rebase || Bind ||
-      LazyBind || WeakBind || IndirectSymbols || DataInCode) {
+      LazyBind || WeakBind || IndirectSymbols || DataInCode || LinkOptHints) {
     outs() << Filename;
     if (!ArchiveMemberName.empty())
       outs() << '(' << ArchiveMemberName << ')';
@@ -498,6 +561,8 @@ static void ProcessMachO(StringRef Filename, MachOObjectFile *MachOOF,
     PrintIndirectSymbols(MachOOF, true);
   if (DataInCode)
     PrintDataInCodeTable(MachOOF, true);
+  if (LinkOptHints)
+    PrintLinkOptHints(MachOOF);
   if (Relocations)
     PrintRelocations(MachOOF);
   if (SectionHeaders)