1 files changed, 71 insertions, 0 deletions
diff --git a/mozglue/misc/AutoProfilerLabel.h b/mozglue/misc/AutoProfilerLabel.h
new file mode 100644
index 0000000000..82299c7b15
--- /dev/null
+++ b/mozglue/misc/AutoProfilerLabel.h
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_AutoProfilerLabel_h
+#define mozilla_AutoProfilerLabel_h
+
+#include "mozilla/Attributes.h"
+
+#include "mozilla/Types.h"
+#include <tuple>
+
+// The Gecko Profiler defines AutoProfilerLabel, an RAII class for
+// pushing/popping frames to/from the ProfilingStack.
+//
+// This file defines a class of the same name that does much the same thing,
+// but which can be used in (and only in) mozglue. A different class is
+// necessary because mozglue cannot directly access sProfilingStack.
+//
+// Note that this class is slightly slower than the other AutoProfilerLabel,
+// and it lacks the macro wrappers. It also is effectively hardwired to use
+// JS::ProfilingCategory::OTHER as the category pair, because that's what
+// the callbacks provided by the profiler use. (Specifying the categories in
+// this file would require #including ProfilingCategory.h in mozglue, which we
+// don't want to do.)
+
+namespace mozilla {
+
+// Enter should return a pointer that will be given to Exit.
+typedef void* (*ProfilerLabelEnter)(const char* aLabel,
+                                    const char* aDynamicString, void* aSp);
+typedef void (*ProfilerLabelExit)(void* EntryContext);
+
+// Register callbacks that do the entry/exit work involving sProfilingStack.
+MFBT_API void RegisterProfilerLabelEnterExit(ProfilerLabelEnter aEnter,
+                                             ProfilerLabelExit aExit);
+
+// This #ifdef prevents this AutoProfilerLabel from being defined in libxul,
+// which would conflict with the one in the profiler.
+#ifdef IMPL_MFBT
+
+class MOZ_RAII AutoProfilerLabel {
+ public:
+  AutoProfilerLabel(const char* aLabel, const char* aDynamicString);
+  ~AutoProfilerLabel();
+
+ private:
+  void* mEntryContext;
+  // Number of RegisterProfilerLabelEnterExit calls, to avoid giving an entry
+  // context from one generation to the next.
+  uint32_t mGeneration;
+};
+
+using ProfilerLabel = std::tuple<void*, uint32_t>;
+
+bool IsProfilerPresent();
+ProfilerLabel ProfilerLabelBegin(const char* aLabelName,
+                                 const char* aDynamicString, void* aSp);
+void ProfilerLabelEnd(const ProfilerLabel& aLabel);
+
+inline bool IsValidProfilerLabel(const ProfilerLabel& aLabel) {
+  return !!std::get<0>(aLabel);
+}
+
+#endif
+
+}  // namespace mozilla
+
+#endif  // mozilla_AutoProfilerLabel_h