Fixed x64 disassembler for cmpb_al

Review URL: https://codereview.chromium.org/11666007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13268 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/disasm-x64.cc

@@ -1731,6 +1731,11 @@ int DisassemblerX64::InstructionDecode(v8::internal::Vector<char> out_buffer,
         data += F6F7Instruction(data);
         break;
 
+      case 0x3C:
+        AppendToBuffer("cmp al, 0x%x", *reinterpret_cast<int8_t*>(data + 1));
+        data +=2;
+        break;
+
       default:
         UnimplementedInstruction();
         data += 1;