1/*
2 * Copyright (C) 2013-2018 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#pragma once
27
28#if ENABLE(DFG_JIT)
29
30#include "CodeBlock.h"
31#include "CompilationResult.h"
32#include "DFGCommonData.h"
33#include "DFGMinifiedGraph.h"
34#include "DFGOSREntry.h"
35#include "DFGOSRExit.h"
36#include "DFGVariableEventStream.h"
37#include "ExecutionCounter.h"
38#include "JITCode.h"
39#include <wtf/SegmentedVector.h>
40
41namespace JSC {
42
43class TrackedReferences;
44
45namespace DFG {
46
47class JITCompiler;
48
49class JITCode : public DirectJITCode {
50public:
51 JITCode();
52 virtual ~JITCode();
53
54 CommonData* dfgCommon() override;
55 JITCode* dfg() override;
56
57 OSREntryData* appendOSREntryData(unsigned bytecodeIndex, CodeLocationLabel<OSREntryPtrTag> machineCode)
58 {
59 DFG::OSREntryData entry;
60 entry.m_bytecodeIndex = bytecodeIndex;
61 entry.m_machineCode = machineCode;
62 osrEntry.append(entry);
63 return &osrEntry.last();
64 }
65
66 OSREntryData* osrEntryDataForBytecodeIndex(unsigned bytecodeIndex)
67 {
68 return tryBinarySearch<OSREntryData, unsigned>(
69 osrEntry, osrEntry.size(), bytecodeIndex,
70 getOSREntryDataBytecodeIndex);
71 }
72
73 void finalizeOSREntrypoints();
74
75 unsigned appendOSRExit(const OSRExit& exit)
76 {
77 unsigned result = osrExit.size();
78 osrExit.append(exit);
79 return result;
80 }
81
82 OSRExit& lastOSRExit()
83 {
84 return osrExit.last();
85 }
86
87 unsigned appendSpeculationRecovery(const SpeculationRecovery& recovery)
88 {
89 unsigned result = speculationRecovery.size();
90 speculationRecovery.append(recovery);
91 return result;
92 }
93
94 void reconstruct(
95 CodeBlock*, CodeOrigin, unsigned streamIndex, Operands<ValueRecovery>& result);
96
97 // This is only applicable if we're at a point where all values are spilled to the
98 // stack. Currently, it also has the restriction that the values must be in their
99 // bytecode-designated stack slots.
100 void reconstruct(
101 ExecState*, CodeBlock*, CodeOrigin, unsigned streamIndex, Operands<Optional<JSValue>>& result);
102
103#if ENABLE(FTL_JIT)
104 // NB. All of these methods take CodeBlock* because they may want to use
105 // CodeBlock's logic about scaling thresholds. It should be a DFG CodeBlock.
106
107 bool checkIfOptimizationThresholdReached(CodeBlock*);
108 void optimizeNextInvocation(CodeBlock*);
109 void dontOptimizeAnytimeSoon(CodeBlock*);
110 void optimizeAfterWarmUp(CodeBlock*);
111 void optimizeSoon(CodeBlock*);
112 void forceOptimizationSlowPathConcurrently(CodeBlock*);
113 void setOptimizationThresholdBasedOnCompilationResult(CodeBlock*, CompilationResult);
114#endif // ENABLE(FTL_JIT)
115
116 void validateReferences(const TrackedReferences&) override;
117
118 void shrinkToFit();
119
120 RegisterSet liveRegistersToPreserveAtExceptionHandlingCallSite(CodeBlock*, CallSiteIndex) override;
121#if ENABLE(FTL_JIT)
122 CodeBlock* osrEntryBlock() { return m_osrEntryBlock.get(); }
123 void setOSREntryBlock(VM&, const JSCell* owner, CodeBlock* osrEntryBlock);
124 void clearOSREntryBlockAndResetThresholds(CodeBlock* dfgCodeBlock);
125#endif
126
127 static ptrdiff_t commonDataOffset() { return OBJECT_OFFSETOF(JITCode, common); }
128
129 Optional<CodeOrigin> findPC(CodeBlock*, void* pc) override;
130
131 using DirectJITCode::initializeCodeRefForDFG;
132
133private:
134 friend class JITCompiler; // Allow JITCompiler to call setCodeRef().
135
136public:
137 CommonData common;
138 Vector<DFG::OSREntryData> osrEntry;
139 SegmentedVector<DFG::OSRExit, 8> osrExit;
140 Vector<DFG::SpeculationRecovery> speculationRecovery;
141 DFG::VariableEventStream variableEventStream;
142 DFG::MinifiedGraph minifiedDFG;
143
144#if ENABLE(FTL_JIT)
145 uint8_t neverExecutedEntry { 1 };
146
147 UpperTierExecutionCounter tierUpCounter;
148
149 // For osrEntryPoint that are in inner loop, this maps their bytecode to the bytecode
150 // of the outerloop entry points in order (from innermost to outermost).
151 //
152 // The key may not always be a target for OSR Entry but the list in the value is guaranteed
153 // to be usable for OSR Entry.
154 HashMap<unsigned, Vector<unsigned>> tierUpInLoopHierarchy;
155
156 // Map each bytecode of CheckTierUpAndOSREnter to its stream index.
157 HashMap<unsigned, unsigned, WTF::IntHash<unsigned>, WTF::UnsignedWithZeroKeyHashTraits<unsigned>> bytecodeIndexToStreamIndex;
158
159 enum class TriggerReason : uint8_t {
160 DontTrigger,
161 CompilationDone,
162 StartCompilation,
163 };
164
165 // Map each bytecode of CheckTierUpAndOSREnter to its trigger forcing OSR Entry.
166 // This can never be modified after it has been initialized since the addresses of the triggers
167 // are used by the JIT.
168 HashMap<unsigned, TriggerReason> tierUpEntryTriggers;
169
170 // Set of bytecode that were the target of a TierUp operation.
171 HashSet<unsigned, WTF::IntHash<unsigned>, WTF::UnsignedWithZeroKeyHashTraits<unsigned>> tierUpEntrySeen;
172
173 WriteBarrier<CodeBlock> m_osrEntryBlock;
174 unsigned osrEntryRetry;
175 bool abandonOSREntry;
176#endif // ENABLE(FTL_JIT)
177};
178
179} } // namespace JSC::DFG
180
181#endif // ENABLE(DFG_JIT)
182