Fixed a bug in llvm-objdump when disassembling using -macho option for a binary

containing no symbols.  Fixed the crash and fixed it not disassembling anything.

llvm-svn: 157031

1 files changed, 29 insertions, 2 deletions

diff --git a/llvm/tools/llvm-objdump/MachODump.cpp b/llvm/tools/llvm-objdump/MachODump.cpp
index 60c33f27892..5e175a004d4 100644
--- a/llvm/tools/llvm-objdump/MachODump.cpp
+++ b/llvm/tools/llvm-objdump/MachODump.cpp
@@ -286,8 +286,10 @@ void llvm::DisassembleInputMachO(StringRef Filename) {
 
   // Read and register the symbol table data.
   InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
-  MachOObj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
-  MachOObj->RegisterStringTable(*SymtabLC);
+  if (SymtabLCI) {
+    MachOObj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
+    MachOObj->RegisterStringTable(*SymtabLC);
+  }
 
   std::vector<SectionRef> Sections;
   std::vector<SymbolRef> Symbols;
@@ -498,6 +500,31 @@ void llvm::DisassembleInputMachO(StringRef Filename) {
             InstrAnalysis.get(), Start, DebugOut, FunctionMap, Functions);
       }
     }
+    if (!CFG && !symbolTableWorked) {
+      // Reading the symbol table didn't work, disassemble the whole section. 
+      uint64_t SectAddress;
+      Sections[SectIdx].getAddress(SectAddress);
+      uint64_t SectSize;
+      Sections[SectIdx].getSize(SectSize);
+      uint64_t InstSize;
+      for (uint64_t Index = 0; Index < SectSize; Index += InstSize) {
+	MCInst Inst;
+
+	if (DisAsm->getInstruction(Inst, InstSize, memoryObject, Index,
+				   DebugOut, nulls())) {
+	  outs() << format("%8" PRIx64 ":\t", SectAddress + Index);
+
+	  DumpBytes(StringRef(Bytes.data() + Index, InstSize));
+	  IP->printInst(&Inst, outs(), "");
+
+	  outs() << "\n";
+	} else {
+	  errs() << "llvm-objdump: warning: invalid instruction encoding\n";
+	  if (InstSize == 0)
+	    InstSize = 1; // skip illegible bytes
+	}
+      }
+    }
 
     if (CFG) {
       if (!symbolTableWorked) {