1/*
2 * Copyright (C) 2011 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Neither the name of Google Inc. nor the names of its
11 * contributors may be used to endorse or promote products derived from
12 * this software without specific prior written permission.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
15 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
16 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
17 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
18 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
19 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
20 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#ifndef WTF_DynamicAnnotations_h
28#define WTF_DynamicAnnotations_h
29
30/* This file defines dynamic annotations for use with dynamic analysis
31 * tool such as ThreadSanitizer, Valgrind, etc.
32 *
33 * Dynamic annotation is a source code annotation that affects
34 * the generated code (that is, the annotation is not a comment).
35 * Each such annotation is attached to a particular
36 * instruction and/or to a particular object (address) in the program.
37 *
38 * By using dynamic annotations a developer can give more details to the dynamic
39 * analysis tool to improve its precision.
40 *
41 * In C/C++ program the annotations are represented as C macros.
42 * With the default build flags, these macros are empty, hence don't affect
43 * performance of a compiled binary.
44 * If dynamic annotations are enabled, they just call no-op functions.
45 * The dynamic analysis tools can intercept these functions and replace them
46 * with their own implementations.
47 *
48 * See http://code.google.com/p/data-race-test/wiki/DynamicAnnotations for more information.
49 */
50
51#if USE(DYNAMIC_ANNOTATIONS)
52/* Tell data race detector that we're not interested in reports on the given address range. */
53#define WTF_ANNOTATE_BENIGN_RACE_SIZED(address, size, description) WTFAnnotateBenignRaceSized(__FILE__, __LINE__, address, size, description)
54#define WTF_ANNOTATE_BENIGN_RACE(pointer, description) WTFAnnotateBenignRaceSized(__FILE__, __LINE__, pointer, sizeof(*(pointer)), description)
55
56/* Annotations for user-defined synchronization mechanisms.
57 * These annotations can be used to define happens-before arcs in user-defined
58 * synchronization mechanisms: the race detector will infer an arc from
59 * the former to the latter when they share the same argument pointer.
60 *
61 * The most common case requiring annotations is atomic reference counting:
62 * bool deref() {
63 *     ANNOTATE_HAPPENS_BEFORE(&m_refCount);
64 *     if (!atomicDecrement(&m_refCount)) {
65 *         // m_refCount is now 0
66 *         ANNOTATE_HAPPENS_AFTER(&m_refCount);
67 *         // "return true; happens-after each atomicDecrement of m_refCount"
68 *         return true;
69 *     }
70 *     return false;
71 * }
72 */
73#define WTF_ANNOTATE_HAPPENS_BEFORE(address) WTFAnnotateHappensBefore(__FILE__, __LINE__, address)
74#define WTF_ANNOTATE_HAPPENS_AFTER(address) WTFAnnotateHappensAfter(__FILE__, __LINE__, address)
75
76#ifdef __cplusplus
77extern "C" {
78#endif
79/* Don't use these directly, use the above macros instead. */
80void WTFAnnotateBenignRaceSized(const char* file, int line, const volatile void* memory, long size, const char* description);
81void WTFAnnotateHappensBefore(const char* file, int line, const volatile void* address);
82void WTFAnnotateHappensAfter(const char* file, int line, const volatile void* address);
83#ifdef __cplusplus
84} // extern "C"
85#endif
86
87#else // USE(DYNAMIC_ANNOTATIONS)
88/* These macros are empty when dynamic annotations are not enabled so you can
89 * use them without affecting the performance of release binaries. */
90#define WTF_ANNOTATE_BENIGN_RACE_SIZED(address, size, description)
91#define WTF_ANNOTATE_BENIGN_RACE(pointer, description)
92#define WTF_ANNOTATE_HAPPENS_BEFORE(address)
93#define WTF_ANNOTATE_HAPPENS_AFTER(address)
94#endif // USE(DYNAMIC_ANNOTATIONS)
95
96#endif // WTF_DynamicAnnotations_h
97