Reimplement profiler sampler on Mac OS X to get it working under Chromium.

src/platform-win32.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1758 matching lines @@
   // Sampler thread handler.
   void Runner() {
     // Context used for sampling the register state of the profiled thread.
     CONTEXT context;
     memset(&context, 0, sizeof(context));
     // Loop until the sampler is disengaged.
     while (sampler_->IsActive()) {
       TickSample sample;
 
       // If profiling, we record the pc and sp of the profiled thread.
-      if (sampler_->IsProfiling()) {
-        // Pause the profiled thread and get its context.
-        SuspendThread(profiled_thread_);
+      if (sampler_->IsProfiling()
+          && SuspendThread(profiled_thread_) != (DWORD)-1) {
         context.ContextFlags = CONTEXT_FULL;
-        GetThreadContext(profiled_thread_, &context);
-        // Invoke tick handler with program counter and stack pointer.
+        if (GetThreadContext(profiled_thread_, &context) != 0) {
 #if V8_HOST_ARCH_X64
-        UNIMPLEMENTED();
-        sample.pc = context.Rip;
-        sample.sp = context.Rsp;
-        sample.fp = context.Rbp;
+          UNIMPLEMENTED();
+          sample.pc = context.Rip;
+          sample.sp = context.Rsp;
+          sample.fp = context.Rbp;
 #else
-        sample.pc = context.Eip;
-        sample.sp = context.Esp;
-        sample.fp = context.Ebp;
+          sample.pc = context.Eip;
+          sample.sp = context.Esp;
+          sample.fp = context.Ebp;
 #endif
+          sampler_->SampleStack(&sample);
+        }
+        ResumeThread(profiled_thread_);
       }
 
       // We always sample the VM state.
       sample.state = Logger::state();
+      // Invoke tick handler with program counter and stack pointer.
       sampler_->Tick(&sample);
 
-      if (sampler_->IsProfiling()) {
-        ResumeThread(profiled_thread_);
-      }
-
       // Wait until next sampling.
       Sleep(sampler_->interval_);
     }
   }
 };
 
 
 // Entry point for sampler thread.
 static unsigned int __stdcall SamplerEntry(void* arg) {
   Sampler::PlatformData* data =
@@ skipping 55 matching lines @@
 
   // Release the thread handles
   CloseHandle(data_->sampler_thread_);
   CloseHandle(data_->profiled_thread_);
 }
 
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal