libraries/source/spidermonkey/include-win32-release/js/friend/XrayJitInfo.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  * vim: set ts=8 sts=2 et sw=2 tw=80:
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /*
   8  * JIT info so SpiderMonkey can efficiently work with Gecko XrayWrapper
   9  * instances.
  10  *
  11  * This header is completely irrelevant to non-Gecko embedders.
  12  */
  13
  14 #ifndef js_friend_XrayJitInfo_h
  15 #define js_friend_XrayJitInfo_h
  16
  17 #include <stddef.h>  // size_t
  18
  19 #include "jstypes.h"  // JS_PUBLIC_API
  20
  21 class JS_PUBLIC_API JSObject;
  22
  23 namespace js {
  24
  25 class JS_PUBLIC_API BaseProxyHandler;
  26
  27 }  // namespace js
  28
  29 namespace JS {
  30
  31 // Callbacks and other information for use by the JITs when optimizing accesses
  32 // on xray wrappers.
  33 struct XrayJitInfo {
  34   // Test whether a proxy handler is a cross compartment xray with no
  35   // security checks.
  36   bool (*isCrossCompartmentXray)(const js::BaseProxyHandler* handler);
  37
  38   // Test whether xrays in |obj|'s compartment have expandos of their own,
  39   // instead of sharing them with Xrays from other compartments.
  40   bool (*compartmentHasExclusiveExpandos)(JSObject* obj);
  41
  42   // Proxy reserved slot used by xrays in sandboxes to store their holder
  43   // object.
  44   size_t xrayHolderSlot;
  45
  46   // Reserved slot used by xray holders to store the xray's expando object.
  47   size_t holderExpandoSlot;
  48
  49   // Reserved slot used by xray expandos to store a custom prototype.
  50   size_t expandoProtoSlot;
  51 };
  52
  53 extern JS_PUBLIC_API void SetXrayJitInfo(XrayJitInfo* info);
  54
  55 }  // namespace JS
  56
  57 #endif  // js_friend_XrayJitInfo_h