1/*
2 * Copyright (C) 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 FTLForOSREntryJITCode_h
27#define FTLForOSREntryJITCode_h
28
29#if ENABLE(FTL_JIT)
30
31#include "FTLJITCode.h"
32
33namespace JSC { namespace FTL {
34
35// OSR entry into the FTL has a number of quirks:
36//
37// - OSR entry only happens through special OSR entry compilations. They have their
38//   own CodeBlock and their own JITCode.
39//
40// - We only OSR enter in loop headers that have a null inline call frame.
41//
42// - Each OSR entry compilation allows entry through only one bytecode index.
43
44class ForOSREntryJITCode : public FTL::JITCode {
45public:
46    ForOSREntryJITCode();
47    ~ForOSREntryJITCode();
48
49    void initializeEntryBuffer(VM&, unsigned numCalleeRegisters);
50    ScratchBuffer* entryBuffer() const { return m_entryBuffer; }
51
52    void setBytecodeIndex(unsigned value) { m_bytecodeIndex = value; }
53    unsigned bytecodeIndex() const { return m_bytecodeIndex; }
54
55    void countEntryFailure() { m_entryFailureCount++; }
56    unsigned entryFailureCount() const { return m_entryFailureCount; }
57
58    ForOSREntryJITCode* ftlForOSREntry();
59
60private:
61    ScratchBuffer* m_entryBuffer; // Only for OSR entry code blocks.
62    unsigned m_bytecodeIndex;
63    unsigned m_entryFailureCount;
64};
65
66} } // namespace JSC::FTL
67
68#endif // ENABLE(FLT_JIT)
69
70#endif // FTLForOSREntryJITCode_h
71
72