1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
|
/*
* Copyright (C) 2011 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "DFGOSRExitCompiler.h"
#if ENABLE(DFG_JIT)
#include "CallFrame.h"
#include "DFGCommon.h"
#include "LinkBuffer.h"
#include "RepatchBuffer.h"
namespace JSC { namespace DFG {
extern "C" {
void compileOSRExit(ExecState* exec)
{
SamplingRegion samplingRegion("DFG OSR Exit Compilation");
CodeBlock* codeBlock = exec->codeBlock();
ASSERT(codeBlock);
ASSERT(codeBlock->getJITType() == JITCode::DFGJIT);
JSGlobalData* globalData = &exec->globalData();
uint32_t exitIndex = globalData->osrExitIndex;
OSRExit& exit = codeBlock->osrExit(exitIndex);
// Make sure all code on our inline stack is JIT compiled. This is necessary since
// we may opt to inline a code block even before it had ever been compiled by the
// JIT, but our OSR exit infrastructure currently only works if the target of the
// OSR exit is JIT code. This could be changed since there is nothing particularly
// hard about doing an OSR exit into the interpreter, but for now this seems to make
// sense in that if we're OSR exiting from inlined code of a DFG code block, then
// probably it's a good sign that the thing we're exiting into is hot. Even more
// interestingly, since the code was inlined, it may never otherwise get JIT
// compiled since the act of inlining it may ensure that it otherwise never runs.
for (CodeOrigin codeOrigin = exit.m_codeOrigin; codeOrigin.inlineCallFrame; codeOrigin = codeOrigin.inlineCallFrame->caller) {
static_cast<FunctionExecutable*>(codeOrigin.inlineCallFrame->executable.get())
->baselineCodeBlockFor(codeOrigin.inlineCallFrame->isCall ? CodeForCall : CodeForConstruct)
->jitCompile(exec);
}
// Compute the value recoveries.
Operands<ValueRecovery> operands;
codeBlock->variableEventStream().reconstruct(codeBlock, exit.m_codeOrigin, codeBlock->minifiedDFG(), exit.m_streamIndex, operands);
// There may be overrides, for forward speculations.
for (size_t i = 0; i < exit.m_valueRecoveryOverrides.size(); i++)
operands.setOperand(exit.m_valueRecoveryOverrides[i]->operand, exit.m_valueRecoveryOverrides[i]->recovery);
SpeculationRecovery* recovery = 0;
if (exit.m_recoveryIndex)
recovery = &codeBlock->speculationRecovery(exit.m_recoveryIndex - 1);
#if DFG_ENABLE(DEBUG_VERBOSE)
dataLog("Generating OSR exit #%u (seq#%u, bc#%u, @%u, %s) for code block %p.\n", exitIndex, exit.m_streamIndex, exit.m_codeOrigin.bytecodeIndex, exit.m_nodeIndex, exitKindToString(exit.m_kind), codeBlock);
#endif
{
CCallHelpers jit(globalData, codeBlock);
OSRExitCompiler exitCompiler(jit);
jit.jitAssertHasValidCallFrame();
exitCompiler.compileExit(exit, operands, recovery);
LinkBuffer patchBuffer(*globalData, &jit, codeBlock);
exit.m_code = FINALIZE_CODE_IF(
shouldShowDisassembly(),
patchBuffer,
("DFG OSR exit #%u (bc#%u, @%u, %s) from CodeBlock %p",
exitIndex, exit.m_codeOrigin.bytecodeIndex, exit.m_nodeIndex,
exitKindToString(exit.m_kind), codeBlock));
}
{
RepatchBuffer repatchBuffer(codeBlock);
repatchBuffer.relink(exit.m_check.codeLocationForRepatch(codeBlock), CodeLocationLabel(exit.m_code.code()));
}
globalData->osrExitJumpDestination = exit.m_code.code().executableAddress();
}
} // extern "C"
void OSRExitCompiler::handleExitCounts(const OSRExit& exit)
{
m_jit.add32(AssemblyHelpers::TrustedImm32(1), AssemblyHelpers::AbsoluteAddress(&exit.m_count));
m_jit.move(AssemblyHelpers::TrustedImmPtr(m_jit.codeBlock()), GPRInfo::regT0);
AssemblyHelpers::Jump tooFewFails;
m_jit.load32(AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()), GPRInfo::regT2);
m_jit.add32(AssemblyHelpers::TrustedImm32(1), GPRInfo::regT2);
m_jit.store32(GPRInfo::regT2, AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfOSRExitCounter()));
m_jit.move(AssemblyHelpers::TrustedImmPtr(m_jit.baselineCodeBlock()), GPRInfo::regT0);
tooFewFails = m_jit.branch32(AssemblyHelpers::BelowOrEqual, GPRInfo::regT2, AssemblyHelpers::TrustedImm32(m_jit.codeBlock()->exitCountThresholdForReoptimization()));
// Reoptimize as soon as possible.
#if !NUMBER_OF_ARGUMENT_REGISTERS
m_jit.poke(GPRInfo::regT0);
#else
m_jit.move(GPRInfo::regT0, GPRInfo::argumentGPR0);
ASSERT(GPRInfo::argumentGPR0 != GPRInfo::regT1);
#endif
m_jit.move(AssemblyHelpers::TrustedImmPtr(bitwise_cast<void*>(triggerReoptimizationNow)), GPRInfo::regT1);
m_jit.call(GPRInfo::regT1);
AssemblyHelpers::Jump doneAdjusting = m_jit.jump();
tooFewFails.link(&m_jit);
// Adjust the execution counter such that the target is to only optimize after a while.
int32_t targetValue =
ExecutionCounter::applyMemoryUsageHeuristicsAndConvertToInt(
m_jit.baselineCodeBlock()->counterValueForOptimizeAfterLongWarmUp(),
m_jit.baselineCodeBlock());
m_jit.store32(AssemblyHelpers::TrustedImm32(-targetValue), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecuteCounter()));
targetValue = ExecutionCounter::clippedThreshold(m_jit.codeBlock()->globalObject(), targetValue);
m_jit.store32(AssemblyHelpers::TrustedImm32(targetValue), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionActiveThreshold()));
m_jit.store32(AssemblyHelpers::TrustedImm32(ExecutionCounter::formattedTotalCount(targetValue)), AssemblyHelpers::Address(GPRInfo::regT0, CodeBlock::offsetOfJITExecutionTotalCount()));
doneAdjusting.link(&m_jit);
}
} } // namespace JSC::DFG
#endif // ENABLE(DFG_JIT)
|
