NativeStackSampler implementation for Mac.

base/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 694 matching lines @@
     "process/process_metrics_linux.cc",
     "process/process_metrics_mac.cc",
 
     #"process/process_metrics_openbsd.cc",  # Unused in Chromium build.
     "process/process_metrics_posix.cc",
     "process/process_metrics_win.cc",
     "process/process_posix.cc",
     "process/process_win.cc",
     "profiler/native_stack_sampler.cc",
     "profiler/native_stack_sampler.h",
+    "profiler/native_stack_sampler_mac.cc",
     "profiler/native_stack_sampler_posix.cc",
     "profiler/native_stack_sampler_win.cc",
     "profiler/scoped_profile.cc",
     "profiler/scoped_profile.h",
     "profiler/scoped_tracker.cc",
     "profiler/scoped_tracker.h",
     "profiler/stack_sampling_profiler.cc",
     "profiler/stack_sampling_profiler.h",
     "profiler/tracked_time.cc",
     "profiler/tracked_time.h",
@@ skipping 719 matching lines @@
   }
 
   # Mac or iOS.
   if (is_mac || is_ios) {
     sources -= [
       "memory/shared_memory_posix.cc",
       "native_library_posix.cc",
       "strings/sys_string_conversions_posix.cc",
       "threading/platform_thread_internal_posix.cc",
     ]
+
+    if (is_mac) {
+      sources -= [ "profiler/native_stack_sampler_posix.cc" ]
+    }
   } else {
     # Non-Mac/ios.
     sources -= [
       "files/file_path_watcher_fsevents.cc",
       "files/file_path_watcher_fsevents.h",
       "files/file_path_watcher_kqueue.cc",
       "files/file_path_watcher_kqueue.h",
     ]
   }
 
@@ skipping 344 matching lines @@
 
   loadable_module("scoped_handle_test_dll") {
     sources = [
       "win/scoped_handle_test_dll.cc",
     ]
     deps = [
       ":base",
       "//base/win:base_win_features",
     ]
   }
+}
 
+if (is_win || is_mac) {
   if (current_cpu == "x64") {
     # Must be a shared library so that it can be unloaded during testing.
     shared_library("base_profiler_test_support_library") {
       sources = [
         "profiler/test_support_library.cc",
       ]
       deps = [
         "//build/config/sanitizers:deps",
       ]
     }
@@ skipping 430 matching lines @@
 
   if (use_partition_alloc) {
     sources += [ "allocator/partition_allocator/partition_alloc_unittest.cc" ]
   }
 
   if (is_mac) {
     libs = [
       "CoreFoundation.framework",
       "Foundation.framework",
     ]
+    if (current_cpu == "x64") {
+      data_deps += [ ":base_profiler_test_support_library" ]
+    }
   }
 
   if (is_linux) {
     if (is_desktop_linux) {
       sources += [ "nix/xdg_util_unittest.cc" ]
     }
 
     deps += [ "//base/test:malloc_wrapper" ]
 
     if (!is_component_build) {
@@ skipping 18 matching lines @@
       "debug/proc_maps_linux_unittest.cc",
       "trace_event/trace_event_android_unittest.cc",
     ]
     set_sources_assignment_filter(sources_assignment_filter)
   }
 
   if (is_win) {
     deps += [ "//base:scoped_handle_test_dll" ]
     if (current_cpu == "x64") {
       sources += [ "profiler/win32_stack_frame_unwinder_unittest.cc" ]
-      deps += [ ":base_profiler_test_support_library" ]
+      data_deps += [ ":base_profiler_test_support_library" ]

[Avi (use Gerrit), 2017/02/16 06:11:15]

How does this work without this change? A normal "deps" means that you're
hard-linking a requirement to this support library, which on the Mac at least
means that you can't unload it.

[Mike Wittman, 2017/02/16 21:51:34]

Apparently there's no corresponding restriction on Windows. I just verified that
the module gets unloaded in the test.

[Avi (use Gerrit), 2017/02/17 03:41:09]

:\

This is technically more correct, as the test intends to have an independent
library being loaded and unloaded, rather than unloading one that was
automatically loaded. I'm planning on leaving this in, even if it works today as
is.

[Mike Wittman, 2017/02/17 17:09:15]

I'm fine with this; my comment was just intended to provide context for what's
happening on Windows.

     }
   }
 
   if (use_experimental_allocator_shim) {
     sources += [ "allocator/allocator_shim_unittest.cc" ]
   }
 
   # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
   configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
@@ skipping 328 matching lines @@
 }
 
 fuzzer_test("base_json_correctness_fuzzer") {
   sources = [
     "json/correctness_fuzzer.cc",
   ]
   deps = [
     ":base",
   ]
 }