objdump: Support newer ObjC image info flags

[kastiglione]

Summary

Add support for two additional ObjC image info flags: IS_SIMULATED and
HAS_CATEGORY_CLASS_PROPERTIES.

IS_SIMULATED indicates a Mach-O binary built for iOS simulator.

HAS_CATEGORY_CLASS_PROPERTIES indicates a Mach-O binary built by a compiler
that supports class properties in categories.

[compnerd]

Nice! I like the changes to the objdump, but, would it be possible to roundtrip the object files being added through obj2yaml and yaml2obj rather than checking in binaries?

[kastiglione]

Yep for sure. I will update the tests.

[kastiglione]

@compnerd The mach-o flavor of yaml2obj doesn't support section contents. In light of that, what do you think?

[kastiglione]

For tests, instead of yaml2obj, I'll generate object files via llvm-mc.

[kastiglione]

test without binaries

llvm/trunk/test/tools/llvm-objdump/macho-image-info.test

+# RUN: llvm-mc < %s -triple x86_64-darwin -filetype=obj | llvm-objdump -m -objc-meta-data - | FileCheck %s
+
+.section  __DATA,__objc_imageinfo,regular,no_dead_strip
+.long 0
+.long 96
+
+# CHECK: OBJC_IMAGE_IS_SIMULATED OBJC_IMAGE_HAS_CATEGORY_CLASS_PROPERTIES

llvm/trunk/tools/llvm-objdump/MachODump.cpp

 };
 struct imageInfo_t {
   uint32_t version;
   uint32_t flags;
 };
 /* masks for objc_image_info.flags */
 #define OBJC_IMAGE_IS_REPLACEMENT (1 << 0)
 #define OBJC_IMAGE_SUPPORTS_GC (1 << 1)
+#define OBJC_IMAGE_IS_SIMULATED (1 << 5)
+#define OBJC_IMAGE_HAS_CATEGORY_CLASS_PROPERTIES (1 << 6)
 
 struct message_ref64 {
   uint64_t imp; /* IMP (64-bit pointer) */
   uint64_t sel; /* SEL (64-bit pointer) */
 };
 
 struct message_ref32 {
   uint32_t imp; /* IMP (32-bit pointer) */
static void print_image_info64(SectionRef S, struct DisassembleInfo *info) {
   if (info->O->isLittleEndian() != sys::IsLittleEndianHost)
     swapStruct(o);
   outs() << "  version " << o.version << "\n";
   outs() << "    flags " << format("0x%" PRIx32, o.flags);
   if (o.flags & OBJC_IMAGE_IS_REPLACEMENT)
     outs() << " OBJC_IMAGE_IS_REPLACEMENT";
   if (o.flags & OBJC_IMAGE_SUPPORTS_GC)
     outs() << " OBJC_IMAGE_SUPPORTS_GC";
+  if (o.flags & OBJC_IMAGE_IS_SIMULATED)
+    outs() << " OBJC_IMAGE_IS_SIMULATED";
+  if (o.flags & OBJC_IMAGE_HAS_CATEGORY_CLASS_PROPERTIES)
+    outs() << " OBJC_IMAGE_HAS_CATEGORY_CLASS_PROPERTIES";
   swift_version = (o.flags >> 8) & 0xff;
   if (swift_version != 0) {
     if (swift_version == 1)
       outs() << " Swift 1.0";
     else if (swift_version == 2)
       outs() << " Swift 1.1";
     else if(swift_version == 3)
       outs() << " Swift 2.0";