Implement suspended thread register count for darwin

[fjricci]

The defines might look a bit messy, but we're going to need them for GetRegistersAndSP anyway, so this seemed like the cleanest way to do things.

[kubamracek]

Can we also get an implementation of GetRegistersAndSP? It's hard to see where this patch is heading without the implementation of GetRegistersAndSP.

But if there's something blocking GetRegistersAndSP, then this looks okay to me.

lib/sanitizer_common/sanitizer_stoptheworld_mac.cc

16–17

Btw, do we still need __mips64 here? Darwin certainly doesn' support MIPS...

[fjricci]

In D32165#729513, @kubamracek wrote:

Can we also get an implementation of GetRegistersAndSP? It's hard to see where this patch is heading without the implementation of GetRegistersAndSP.

But if there's something blocking GetRegistersAndSP, then this looks okay to me.

Uploaded the GetRegisters patch here - D32182

lib/sanitizer_common/sanitizer_stoptheworld_mac.cc

16–17

I'll put up a patch to get rid of that, not sure why it was added

[kubamracek]

lib/sanitizer_common/sanitizer_stoptheworld_mac.cc

51–60

Can we use MACHINE_THREAD_STATE_COUNT (should be already defined in system headers) instead?

[fjricci]

Use MACHINE_THREAD_STATE_COUNT

lib/sanitizer_common/sanitizer_stoptheworld_mac.cc

 //===-- sanitizer_stoptheworld_mac.cc -------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // See sanitizer_stoptheworld.h for details.
 //
 //===----------------------------------------------------------------------===//
 
 #include "sanitizer_platform.h"
 
 #if SANITIZER_MAC && (defined(__x86_64__) || defined(__aarch64__) || \
                       defined(__mips64) || defined(__i386))
 
 #include <mach/mach.h>
 
 #include "sanitizer_stoptheworld.h"
 
 namespace __sanitizer {
 typedef struct {
   tid_t tid;

  private:
   InternalMmapVector<SuspendedThreadInfo> threads_;
 };
 
 void StopTheWorld(StopTheWorldCallback callback, void *argument) {
   CHECK(0 && "unimplemented");
 }
 
 tid_t SuspendedThreadsListMac::GetThreadID(uptr index) const {
   CHECK_LT(index, threads_.size());
   return threads_[index].tid;
 }
 
 thread_t SuspendedThreadsListMac::GetThread(uptr index) const {
   CHECK_LT(index, threads_.size());
   return threads_[index].thread;
 }
 
 uptr SuspendedThreadsListMac::ThreadCount() const {
   return threads_.size();
 }
 
 bool SuspendedThreadsListMac::ContainsThread(thread_t thread) const {
   for (uptr i = 0; i < threads_.size(); i++) {
     if (threads_[i].thread == thread) return true;
   }

 
 PtraceRegistersStatus SuspendedThreadsListMac::GetRegistersAndSP(
     uptr index, uptr *buffer, uptr *sp) const {
   CHECK(0 && "unimplemented");
   return REGISTERS_UNAVAILABLE_FATAL;
 }
 
 uptr SuspendedThreadsListMac::RegisterCount() const {
-  CHECK(0 && "unimplemented");
-  return 0;
+  return MACHINE_THREAD_STATE_COUNT;
 }
 } // namespace __sanitizer
 
 #endif  // SANITIZER_MAC && (defined(__x86_64__) || defined(__aarch64__)) ||
         //                   defined(__mips64) || defined(__i386))