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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/. */
+
+/*
+ * Provides a common interface to the ASan (AddressSanitizer) and Valgrind
+ * functions used to mark memory in certain ways. In detail, the following
+ * three macros are provided:
+ *
+ * MOZ_MAKE_MEM_NOACCESS - Mark memory as unsafe to access (e.g. freed)
+ * MOZ_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined
+ * MOZ_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined
+ *
+ * With Valgrind in use, these directly map to the three respective Valgrind
+ * macros. With ASan in use, the NOACCESS macro maps to poisoning the memory,
+ * while the UNDEFINED/DEFINED macros unpoison memory.
+ *
+ * With no memory checker available, all macros expand to the empty statement.
+ */
+
+#ifndef mozilla_MemoryChecking_h
+#define mozilla_MemoryChecking_h
+
+#if defined(MOZ_VALGRIND)
+# include "valgrind/memcheck.h"
+#endif
+
+#if defined(MOZ_ASAN) || defined(MOZ_VALGRIND)
+# define MOZ_HAVE_MEM_CHECKS 1
+#endif
+
+#if defined(MOZ_ASAN)
+# include <stddef.h>
+
+# include "mozilla/Attributes.h"
+# include "mozilla/Types.h"
+
+# ifdef _MSC_VER
+// In clang-cl based ASAN, we link against the memory poisoning functions
+// statically.
+# define MOZ_ASAN_VISIBILITY
+# else
+# define MOZ_ASAN_VISIBILITY MOZ_EXPORT
+# endif
+
+extern "C" {
+/* These definitions are usually provided through the
+ * sanitizer/asan_interface.h header installed by ASan.
+ */
+void MOZ_ASAN_VISIBILITY __asan_poison_memory_region(void const volatile* addr,
+ size_t size);
+void MOZ_ASAN_VISIBILITY
+__asan_unpoison_memory_region(void const volatile* addr, size_t size);
+
+# define MOZ_MAKE_MEM_NOACCESS(addr, size) \
+ __asan_poison_memory_region((addr), (size))
+
+# define MOZ_MAKE_MEM_UNDEFINED(addr, size) \
+ __asan_unpoison_memory_region((addr), (size))
+
+# define MOZ_MAKE_MEM_DEFINED(addr, size) \
+ __asan_unpoison_memory_region((addr), (size))
+
+/*
+ * These definitions are usually provided through the
+ * sanitizer/lsan_interface.h header installed by LSan.
+ */
+void MOZ_EXPORT __lsan_ignore_object(const void* p);
+}
+#elif defined(MOZ_MSAN)
+# include <stddef.h>
+
+# include "mozilla/Types.h"
+
+extern "C" {
+/* These definitions are usually provided through the
+ * sanitizer/msan_interface.h header installed by MSan.
+ */
+void MOZ_EXPORT __msan_poison(void const volatile* addr, size_t size);
+void MOZ_EXPORT __msan_unpoison(void const volatile* addr, size_t size);
+
+# define MOZ_MAKE_MEM_NOACCESS(addr, size) __msan_poison((addr), (size))
+
+# define MOZ_MAKE_MEM_UNDEFINED(addr, size) __msan_poison((addr), (size))
+
+# define MOZ_MAKE_MEM_DEFINED(addr, size) __msan_unpoison((addr), (size))
+}
+#elif defined(MOZ_VALGRIND)
+# define MOZ_MAKE_MEM_NOACCESS(addr, size) \
+ VALGRIND_MAKE_MEM_NOACCESS((addr), (size))
+
+# define MOZ_MAKE_MEM_UNDEFINED(addr, size) \
+ VALGRIND_MAKE_MEM_UNDEFINED((addr), (size))
+
+# define MOZ_MAKE_MEM_DEFINED(addr, size) \
+ VALGRIND_MAKE_MEM_DEFINED((addr), (size))
+#else
+
+# define MOZ_MAKE_MEM_NOACCESS(addr, size) \
+ do { \
+ } while (0)
+# define MOZ_MAKE_MEM_UNDEFINED(addr, size) \
+ do { \
+ } while (0)
+# define MOZ_MAKE_MEM_DEFINED(addr, size) \
+ do { \
+ } while (0)
+
+#endif
+
+/*
+ * MOZ_LSAN_INTENTIONAL_LEAK(X) is a macro to tell LeakSanitizer that X
+ * points to a value that will intentionally never be deallocated during
+ * the execution of the process.
+ *
+ * Additional uses of this macro should be reviewed by people
+ * conversant in leak-checking and/or MFBT peers.
+ */
+#if defined(MOZ_ASAN)
+# define MOZ_LSAN_INTENTIONALLY_LEAK_OBJECT(X) __lsan_ignore_object(X)
+#else
+# define MOZ_LSAN_INTENTIONALLY_LEAK_OBJECT(X) /* nothing */
+#endif // defined(MOZ_ASAN)
+
+#endif /* mozilla_MemoryChecking_h */