NativeStackSampler implementation for Mac.

chrome/common/stack_sampling_configuration.cc

Index: chrome/common/stack_sampling_configuration.cc
diff --git a/chrome/common/stack_sampling_configuration.cc b/chrome/common/stack_sampling_configuration.cc
index c2b0786442b1541f0c0f2ec144f5b300a16f3585..7379727e7acd7e34af1cdd262bf76c1314d3d2ef 100644
--- a/chrome/common/stack_sampling_configuration.cc
+++ b/chrome/common/stack_sampling_configuration.cc
@@ -5,6 +5,7 @@
 #include "chrome/common/stack_sampling_configuration.h"
 
 #include "base/command_line.h"
+#include "base/compiler_specific.h"

[Mark Mentovai, 2017/03/16 03:08:46]

I don’t know if you need this for anything, but "build/build_config.h" is needed
for OS_MACOSX, and while "base/compiler_specific.h" does #include that, you
ought to IWYU.

[Avi (use Gerrit), 2017/03/18 03:09:28]

Yes, that's the one that I meant.

 #include "base/lazy_instance.h"
 #include "base/rand_util.h"
 #include "chrome/common/channel_info.h"
@@ -17,16 +18,20 @@ namespace {
 base::LazyInstance<StackSamplingConfiguration>::Leaky g_configuration =
     LAZY_INSTANCE_INITIALIZER;
 
-// The profiler is currently only implemented for Windows x64, and only runs on
-// trunk, canary, and dev.
+// The profiler is currently only implemented for Windows x64 and Mac x64.
 bool IsProfilerSupported() {
-#if !defined(_WIN64)
-  return false;
-#else
+#if defined(_WIN64)

[Mark Mentovai, 2017/03/16 03:08:46]

This is multi-platform code, use OS_WIN now.

[Avi (use Gerrit), 2017/03/18 03:09:28]

Done.

+  // Only run on trunk, canary, and dev.
+  const version_info::Channel channel = chrome::GetChannel();
+  return channel == version_info::Channel::UNKNOWN ||
+         channel == version_info::Channel::CANARY ||
+         channel == version_info::Channel::DEV;
+#elif defined(OS_MACOSX)
+  // This is experimental, so only run on trunk.

[Mark Mentovai, 2017/03/16 03:08:46]

“unknown” doesn’t really mean trunk, it just means non-Chrome-branded. And a
more direct way to say that is

#if defined(GOOGLE_CHROME_BUILD)
  return false;
#else
  return true;
#endif

[Avi (use Gerrit), 2017/03/18 03:09:28]

Done.

   const version_info::Channel channel = chrome::GetChannel();
-  return (channel == version_info::Channel::UNKNOWN ||
-          channel == version_info::Channel::CANARY ||
-          channel == version_info::Channel::DEV);
+  return channel == version_info::Channel::UNKNOWN;
+#else
+  return false;
 #endif
 }