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#include "config.h"
27#include "DFGTierUpCheckInjectionPhase.h"
28
29#if ENABLE(DFG_JIT)
30
31#include "DFGGraph.h"
32#include "DFGInsertionSet.h"
33#include "DFGNaturalLoops.h"
34#include "DFGPhase.h"
35#include "FTLCapabilities.h"
36#include "FunctionWhitelist.h"
37#include "JSCInlines.h"
38#include <wtf/NeverDestroyed.h>
39
40namespace JSC { namespace DFG {
41
42static FunctionWhitelist& ensureGlobalFTLWhitelist()
43{
44 static LazyNeverDestroyed<FunctionWhitelist> ftlWhitelist;
45 static std::once_flag initializeWhitelistFlag;
46 std::call_once(initializeWhitelistFlag, [] {
47 const char* functionWhitelistFile = Options::ftlWhitelist();
48 ftlWhitelist.construct(functionWhitelistFile);
49 });
50 return ftlWhitelist;
51}
52
53using NaturalLoop = CPSNaturalLoop;
54
55class TierUpCheckInjectionPhase : public Phase {
56public:
57 TierUpCheckInjectionPhase(Graph& graph)
58 : Phase(graph, "tier-up check injection")
59 {
60 }
61
62 bool run()
63 {
64 RELEASE_ASSERT(m_graph.m_plan.mode() == DFGMode);
65
66 if (!Options::useFTLJIT())
67 return false;
68
69 if (m_graph.m_profiledBlock->m_didFailFTLCompilation)
70 return false;
71
72 if (!Options::bytecodeRangeToFTLCompile().isInRange(m_graph.m_profiledBlock->instructionsSize()))
73 return false;
74
75 if (!ensureGlobalFTLWhitelist().contains(m_graph.m_profiledBlock))
76 return false;
77
78#if ENABLE(FTL_JIT)
79 FTL::CapabilityLevel level = FTL::canCompile(m_graph);
80 if (level == FTL::CannotCompile)
81 return false;
82
83 if (!Options::useOSREntryToFTL())
84 level = FTL::CanCompile;
85
86 m_graph.ensureCPSNaturalLoops();
87 CPSNaturalLoops& naturalLoops = *m_graph.m_cpsNaturalLoops;
88 HashMap<const NaturalLoop*, BytecodeIndex> naturalLoopToLoopHint = buildNaturalLoopToLoopHintMap(naturalLoops);
89
90 HashMap<BytecodeIndex, LoopHintDescriptor> tierUpHierarchy;
91
92 InsertionSet insertionSet(m_graph);
93 for (BlockIndex blockIndex = m_graph.numBlocks(); blockIndex--;) {
94 BasicBlock* block = m_graph.block(blockIndex);
95 if (!block)
96 continue;
97
98 for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
99 Node* node = block->at(nodeIndex);
100 if (node->op() != LoopHint)
101 continue;
102
103 NodeOrigin origin = node->origin;
104 bool canOSREnter = canOSREnterAtLoopHint(level, block, nodeIndex);
105
106 NodeType tierUpType = CheckTierUpAndOSREnter;
107 if (!canOSREnter)
108 tierUpType = CheckTierUpInLoop;
109 insertionSet.insertNode(nodeIndex + 1, SpecNone, tierUpType, origin);
110
111 auto bytecodeIndex = origin.semantic.bytecodeIndex();
112 if (canOSREnter)
113 m_graph.m_plan.tierUpAndOSREnterBytecodes().append(bytecodeIndex);
114
115 if (const NaturalLoop* loop = naturalLoops.innerMostLoopOf(block)) {
116 LoopHintDescriptor descriptor;
117 descriptor.canOSREnter = canOSREnter;
118
119 const NaturalLoop* outerLoop = loop;
120 while ((outerLoop = naturalLoops.innerMostOuterLoop(*outerLoop))) {
121 auto it = naturalLoopToLoopHint.find(outerLoop);
122 if (it != naturalLoopToLoopHint.end())
123 descriptor.osrEntryCandidates.append(it->value);
124 }
125 tierUpHierarchy.add(bytecodeIndex, WTFMove(descriptor));
126 }
127 break;
128 }
129
130 NodeAndIndex terminal = block->findTerminal();
131 if (terminal.node->isFunctionTerminal()) {
132 insertionSet.insertNode(
133 terminal.index, SpecNone, CheckTierUpAtReturn, terminal.node->origin);
134 }
135
136 insertionSet.execute(block);
137 }
138
139 // Add all the candidates that can be OSR Entered.
140 for (auto entry : tierUpHierarchy) {
141 Vector<BytecodeIndex> tierUpCandidates;
142 for (BytecodeIndex bytecodeIndex : entry.value.osrEntryCandidates) {
143 auto descriptorIt = tierUpHierarchy.find(bytecodeIndex);
144 if (descriptorIt != tierUpHierarchy.end()
145 && descriptorIt->value.canOSREnter)
146 tierUpCandidates.append(bytecodeIndex);
147 }
148
149 if (!tierUpCandidates.isEmpty())
150 m_graph.m_plan.tierUpInLoopHierarchy().add(entry.key, WTFMove(tierUpCandidates));
151 }
152 m_graph.m_plan.setWillTryToTierUp(true);
153 return true;
154#else // ENABLE(FTL_JIT)
155 RELEASE_ASSERT_NOT_REACHED();
156 return false;
157#endif // ENABLE(FTL_JIT)
158 }
159
160private:
161#if ENABLE(FTL_JIT)
162 struct LoopHintDescriptor {
163 Vector<BytecodeIndex> osrEntryCandidates;
164 bool canOSREnter;
165 };
166
167 bool canOSREnterAtLoopHint(FTL::CapabilityLevel level, const BasicBlock* block, unsigned nodeIndex)
168 {
169 Node* node = block->at(nodeIndex);
170 ASSERT(node->op() == LoopHint);
171
172 NodeOrigin origin = node->origin;
173 if (level != FTL::CanCompileAndOSREnter || origin.semantic.inlineCallFrame())
174 return false;
175
176 // We only put OSR checks for the first LoopHint in the block. Note that
177 // more than one LoopHint could happen in cases where we did a lot of CFG
178 // simplification in the bytecode parser, but it should be very rare.
179 for (unsigned subNodeIndex = nodeIndex; subNodeIndex--;) {
180 if (!block->at(subNodeIndex)->isSemanticallySkippable())
181 return false;
182 }
183 return true;
184 }
185
186 HashMap<const NaturalLoop*, BytecodeIndex> buildNaturalLoopToLoopHintMap(const CPSNaturalLoops& naturalLoops)
187 {
188 HashMap<const NaturalLoop*, BytecodeIndex> naturalLoopsToLoopHint;
189
190 for (BasicBlock* block : m_graph.blocksInNaturalOrder()) {
191 for (unsigned nodeIndex = 0; nodeIndex < block->size(); ++nodeIndex) {
192 Node* node = block->at(nodeIndex);
193 if (node->op() != LoopHint)
194 continue;
195
196 if (const NaturalLoop* loop = naturalLoops.innerMostLoopOf(block)) {
197 BytecodeIndex bytecodeIndex = node->origin.semantic.bytecodeIndex();
198 naturalLoopsToLoopHint.add(loop, bytecodeIndex);
199 }
200 break;
201 }
202 }
203 return naturalLoopsToLoopHint;
204 }
205#endif
206};
207
208bool performTierUpCheckInjection(Graph& graph)
209{
210 return runPhase<TierUpCheckInjectionPhase>(graph);
211}
212
213} } // namespace JSC::DFG
214
215#endif // ENABLE(DFG_JIT)
216
217
218