1/*
2 * Copyright (C) 2012, 2013 Apple 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef ProfilerDatabase_h
27#define ProfilerDatabase_h
28
29#include "JSCJSValue.h"
30#include "ProfilerBytecodes.h"
31#include "ProfilerCompilation.h"
32#include "ProfilerCompilationKind.h"
33#include <wtf/FastMalloc.h>
34#include <wtf/HashMap.h>
35#include <wtf/Noncopyable.h>
36#include <wtf/PassRefPtr.h>
37#include <wtf/SegmentedVector.h>
38#include <wtf/ThreadingPrimitives.h>
39#include <wtf/text/WTFString.h>
40
41namespace JSC { namespace Profiler {
42
43class Database {
44    WTF_MAKE_FAST_ALLOCATED; WTF_MAKE_NONCOPYABLE(Database);
45public:
46    JS_EXPORT_PRIVATE Database(VM&);
47    JS_EXPORT_PRIVATE ~Database();
48
49    int databaseID() const { return m_databaseID; }
50
51    Bytecodes* ensureBytecodesFor(CodeBlock*);
52    void notifyDestruction(CodeBlock*);
53
54    void addCompilation(PassRefPtr<Compilation>);
55
56    // Converts the database to a JavaScript object that is suitable for JSON stringification.
57    // Note that it's probably a good idea to use an ExecState* associated with a global
58    // object that is "clean" - i.e. array and object prototypes haven't had strange things
59    // done to them. And yes, it should be appropriate to just use a globalExec here.
60    JS_EXPORT_PRIVATE JSValue toJS(ExecState*) const;
61
62    // Converts the database to a JavaScript object using a private temporary global object,
63    // and then returns the JSON representation of that object.
64    JS_EXPORT_PRIVATE String toJSON() const;
65
66    // Saves the JSON representation (from toJSON()) to the given file. Returns false if the
67    // save failed.
68    JS_EXPORT_PRIVATE bool save(const char* filename) const;
69
70    void registerToSaveAtExit(const char* filename);
71
72private:
73    // Use a full-blown adaptive mutex because:
74    // - There is only one ProfilerDatabase per VM. The size overhead of the system's
75    //   mutex is negligible if you only have one of them.
76    // - It's locked infrequently - once per bytecode generation, compilation, and
77    //   code block collection - so the fact that the fast path still requires a
78    //   function call is neglible.
79    // - It tends to be held for a while. Currently, we hold it while generating
80    //   Profiler::Bytecodes for a CodeBlock. That's uncommon and shouldn't affect
81    //   performance, but if we did have contention, we would want a sensible,
82    //   power-aware backoff. An adaptive mutex will do this as a matter of course,
83    //   but a spinlock won't.
84    typedef Mutex Lock;
85    typedef MutexLocker Locker;
86
87
88    void addDatabaseToAtExit();
89    void removeDatabaseFromAtExit();
90    void performAtExitSave() const;
91    static Database* removeFirstAtExitDatabase();
92    static void atExitCallback();
93
94    int m_databaseID;
95    VM& m_vm;
96    SegmentedVector<Bytecodes> m_bytecodes;
97    HashMap<CodeBlock*, Bytecodes*> m_bytecodesMap;
98    Vector<RefPtr<Compilation>> m_compilations;
99    bool m_shouldSaveAtExit;
100    CString m_atExitSaveFilename;
101    Database* m_nextRegisteredDatabase;
102    Lock m_lock;
103};
104
105} } // namespace JSC::Profiler
106
107#endif // ProfilerDatabase_h
108
109