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
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
|
#pragma once
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-parameter"
#endif
//===------ LazyReexports.h -- Utilities for lazy reexports -----*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Lazy re-exports are similar to normal re-exports, except that for callable
// symbols the definitions are replaced with trampolines that will look up and
// call through to the re-exported symbol at runtime. This can be used to
// enable lazy compilation.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_EXECUTIONENGINE_ORC_LAZYREEXPORTS_H
#define LLVM_EXECUTIONENGINE_ORC_LAZYREEXPORTS_H
#include "llvm/ADT/STLExtras.h"
#include "llvm/ExecutionEngine/Orc/Core.h"
#include "llvm/ExecutionEngine/Orc/IndirectionUtils.h"
#include "llvm/ExecutionEngine/Orc/Speculation.h"
namespace llvm {
class Triple;
namespace orc {
/// Manages a set of 'lazy call-through' trampolines. These are compiler
/// re-entry trampolines that are pre-bound to look up a given symbol in a given
/// JITDylib, then jump to that address. Since compilation of symbols is
/// triggered on first lookup, these call-through trampolines can be used to
/// implement lazy compilation.
///
/// The easiest way to construct these call-throughs is using the lazyReexport
/// function.
class LazyCallThroughManager {
public:
using NotifyResolvedFunction =
unique_function<Error(JITTargetAddress ResolvedAddr)>;
LazyCallThroughManager(ExecutionSession &ES,
JITTargetAddress ErrorHandlerAddr, TrampolinePool *TP);
// Return a free call-through trampoline and bind it to look up and call
// through to the given symbol.
Expected<JITTargetAddress>
getCallThroughTrampoline(JITDylib &SourceJD, SymbolStringPtr SymbolName,
NotifyResolvedFunction NotifyResolved);
void resolveTrampolineLandingAddress(
JITTargetAddress TrampolineAddr,
TrampolinePool::NotifyLandingResolvedFunction NotifyLandingResolved);
virtual ~LazyCallThroughManager() = default;
protected:
using NotifyLandingResolvedFunction =
TrampolinePool::NotifyLandingResolvedFunction;
struct ReexportsEntry {
JITDylib *SourceJD;
SymbolStringPtr SymbolName;
};
JITTargetAddress reportCallThroughError(Error Err);
Expected<ReexportsEntry> findReexport(JITTargetAddress TrampolineAddr);
Error notifyResolved(JITTargetAddress TrampolineAddr,
JITTargetAddress ResolvedAddr);
void setTrampolinePool(TrampolinePool &TP) { this->TP = &TP; }
private:
using ReexportsMap = std::map<JITTargetAddress, ReexportsEntry>;
using NotifiersMap = std::map<JITTargetAddress, NotifyResolvedFunction>;
std::mutex LCTMMutex;
ExecutionSession &ES;
JITTargetAddress ErrorHandlerAddr;
TrampolinePool *TP = nullptr;
ReexportsMap Reexports;
NotifiersMap Notifiers;
};
/// A lazy call-through manager that builds trampolines in the current process.
class LocalLazyCallThroughManager : public LazyCallThroughManager {
private:
using NotifyTargetResolved = unique_function<void(JITTargetAddress)>;
LocalLazyCallThroughManager(ExecutionSession &ES,
JITTargetAddress ErrorHandlerAddr)
: LazyCallThroughManager(ES, ErrorHandlerAddr, nullptr) {}
template <typename ORCABI> Error init() {
auto TP = LocalTrampolinePool<ORCABI>::Create(
[this](JITTargetAddress TrampolineAddr,
TrampolinePool::NotifyLandingResolvedFunction
NotifyLandingResolved) {
resolveTrampolineLandingAddress(TrampolineAddr,
std::move(NotifyLandingResolved));
});
if (!TP)
return TP.takeError();
this->TP = std::move(*TP);
setTrampolinePool(*this->TP);
return Error::success();
}
std::unique_ptr<TrampolinePool> TP;
public:
/// Create a LocalLazyCallThroughManager using the given ABI. See
/// createLocalLazyCallThroughManager.
template <typename ORCABI>
static Expected<std::unique_ptr<LocalLazyCallThroughManager>>
Create(ExecutionSession &ES, JITTargetAddress ErrorHandlerAddr) {
auto LLCTM = std::unique_ptr<LocalLazyCallThroughManager>(
new LocalLazyCallThroughManager(ES, ErrorHandlerAddr));
if (auto Err = LLCTM->init<ORCABI>())
return std::move(Err);
return std::move(LLCTM);
}
};
/// Create a LocalLazyCallThroughManager from the given triple and execution
/// session.
Expected<std::unique_ptr<LazyCallThroughManager>>
createLocalLazyCallThroughManager(const Triple &T, ExecutionSession &ES,
JITTargetAddress ErrorHandlerAddr);
/// A materialization unit that builds lazy re-exports. These are callable
/// entry points that call through to the given symbols.
/// Unlike a 'true' re-export, the address of the lazy re-export will not
/// match the address of the re-exported symbol, but calling it will behave
/// the same as calling the re-exported symbol.
class LazyReexportsMaterializationUnit : public MaterializationUnit {
public:
LazyReexportsMaterializationUnit(LazyCallThroughManager &LCTManager,
IndirectStubsManager &ISManager,
JITDylib &SourceJD,
SymbolAliasMap CallableAliases,
ImplSymbolMap *SrcJDLoc);
StringRef getName() const override;
private:
void materialize(std::unique_ptr<MaterializationResponsibility> R) override;
void discard(const JITDylib &JD, const SymbolStringPtr &Name) override;
static MaterializationUnit::Interface
extractFlags(const SymbolAliasMap &Aliases);
LazyCallThroughManager &LCTManager;
IndirectStubsManager &ISManager;
JITDylib &SourceJD;
SymbolAliasMap CallableAliases;
ImplSymbolMap *AliaseeTable;
};
/// Define lazy-reexports based on the given SymbolAliasMap. Each lazy re-export
/// is a callable symbol that will look up and dispatch to the given aliasee on
/// first call. All subsequent calls will go directly to the aliasee.
inline std::unique_ptr<LazyReexportsMaterializationUnit>
lazyReexports(LazyCallThroughManager &LCTManager,
IndirectStubsManager &ISManager, JITDylib &SourceJD,
SymbolAliasMap CallableAliases,
ImplSymbolMap *SrcJDLoc = nullptr) {
return std::make_unique<LazyReexportsMaterializationUnit>(
LCTManager, ISManager, SourceJD, std::move(CallableAliases), SrcJDLoc);
}
} // End namespace orc
} // End namespace llvm
#endif // LLVM_EXECUTIONENGINE_ORC_LAZYREEXPORTS_H
#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif
|
