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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /js/src/jsapi-tests/hidePointer.cpp
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'js/src/jsapi-tests/hidePointer.cpp')
-rw-r--r--js/src/jsapi-tests/hidePointer.cpp25
1 files changed, 25 insertions, 0 deletions
diff --git a/js/src/jsapi-tests/hidePointer.cpp b/js/src/jsapi-tests/hidePointer.cpp
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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/. */
+
+#include "mozilla/Atomics.h"
+
+// This is an attempt to hide pointer values from the C++ compiler. This might
+// not stand up in the presence of PGO but that's probably not important.
+
+// g_hidden_pointer is public so that it's limited what the compiler can assume
+// about it, and atomic so that we don't run afoul of the compiler's UB
+// analysis.
+
+mozilla::Atomic<void*> g_hidden_pointer;
+
+// Call this to install a pointer into the global.
+
+MOZ_NEVER_INLINE void setHiddenPointer(void* p) { g_hidden_pointer = p; }
+
+// Call this to retrieve the pointer.
+
+MOZ_NEVER_INLINE void* getHiddenPointer() { return g_hidden_pointer; }