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diff --git a/js/public/AllocationRecording.h b/js/public/AllocationRecording.h
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+/* -*- Mode: C++; tab-width: 8; 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 js_AllocationRecording_h
+#define js_AllocationRecording_h
+
+#include <stdint.h>
+#include "jstypes.h"
+#include "js/TypeDecls.h"
+
+namespace JS {
+
+/**
+ * This struct holds the information needed to create a profiler marker payload
+ * that can represent a JS allocation. It translates JS engine specific classes,
+ * into something that can be used in the profiler.
+ */
+struct RecordAllocationInfo {
+  RecordAllocationInfo(const char16_t* typeName, const char* className,
+                       const char16_t* descriptiveTypeName,
+                       const char* coarseType, uint64_t size, bool inNursery)
+      : typeName(typeName),
+        className(className),
+        descriptiveTypeName(descriptiveTypeName),
+        coarseType(coarseType),
+        size(size),
+        inNursery(inNursery) {}
+
+  // These pointers are borrowed from the UbiNode, and can point to live data.
+  // It is important for the consumers of this struct to correctly
+  // duplicate the strings to take ownership of them.
+  const char16_t* typeName;
+  const char* className;
+  const char16_t* descriptiveTypeName;
+
+  // The coarseType points to a string literal, so does not need to be
+  // duplicated.
+  const char* coarseType;
+
+  // The size in bytes of the allocation.
+  uint64_t size;
+
+  // Whether or not the allocation is in the nursery or not.
+  bool inNursery;
+};
+
+typedef void (*RecordAllocationsCallback)(RecordAllocationInfo&& info);
+
+/**
+ * Enable recording JS allocations. This feature hooks into the object creation
+ * in the JavaScript engine, and reports back the allocation info through the
+ * callback. This allocation tracking is turned on for all encountered realms.
+ * The JS Debugger API can also turn on allocation tracking with its own
+ * probability. If both allocation tracking mechanisms are turned on at the same
+ * time, the Debugger's probability defers to the EnableRecordingAllocations's
+ * probability setting.
+ */
+JS_PUBLIC_API void EnableRecordingAllocations(
+    JSContext* cx, RecordAllocationsCallback callback, double probability);
+
+/**
+ * Turn off JS allocation recording. If any JS Debuggers are also recording
+ * allocations, then the probability will be reset to the Debugger's desired
+ * setting.
+ */
+JS_PUBLIC_API void DisableRecordingAllocations(JSContext* cx);
+
+}  // namespace JS
+
+#endif /* js_AllocationRecording_h */