1 //===-- MCJIT.h - Class definition for the MCJIT ----------------*- C++ -*-===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 #ifndef LLVM_LIB_EXECUTIONENGINE_MCJIT_MCJIT_H
10 #define LLVM_LIB_EXECUTIONENGINE_MCJIT_MCJIT_H
12 #include "llvm/ADT/SmallPtrSet.h"
13 #include "llvm/ADT/SmallVector.h"
14 #include "llvm/ExecutionEngine/ExecutionEngine.h"
15 #include "llvm/ExecutionEngine/RTDyldMemoryManager.h"
16 #include "llvm/ExecutionEngine/RuntimeDyld.h"
23 // This is a helper class that the MCJIT execution engine uses for linking
24 // functions across modules that it owns. It aggregates the memory manager
25 // that is passed in to the MCJIT constructor and defers most functionality
27 class LinkingSymbolResolver
: public LegacyJITSymbolResolver
{
29 LinkingSymbolResolver(MCJIT
&Parent
,
30 std::shared_ptr
<LegacyJITSymbolResolver
> Resolver
)
31 : ParentEngine(Parent
), ClientResolver(std::move(Resolver
)) {}
33 JITSymbol
findSymbol(const std::string
&Name
) override
;
35 // MCJIT doesn't support logical dylibs.
36 JITSymbol
findSymbolInLogicalDylib(const std::string
&Name
) override
{
42 std::shared_ptr
<LegacyJITSymbolResolver
> ClientResolver
;
43 void anchor() override
;
46 // About Module states: added->loaded->finalized.
48 // The purpose of the "added" state is having modules in standby. (added=known
49 // but not compiled). The idea is that you can add a module to provide function
50 // definitions but if nothing in that module is referenced by a module in which
51 // a function is executed (note the wording here because it's not exactly the
52 // ideal case) then the module never gets compiled. This is sort of lazy
55 // The purpose of the "loaded" state (loaded=compiled and required sections
56 // copied into local memory but not yet ready for execution) is to have an
57 // intermediate state wherein clients can remap the addresses of sections, using
58 // MCJIT::mapSectionAddress, (in preparation for later copying to a new location
59 // or an external process) before relocations and page permissions are applied.
61 // It might not be obvious at first glance, but the "remote-mcjit" case in the
62 // lli tool does this. In that case, the intermediate action is taken by the
63 // RemoteMemoryManager in response to the notifyObjectLoaded function being
66 class MCJIT
: public ExecutionEngine
{
67 MCJIT(std::unique_ptr
<Module
> M
, std::unique_ptr
<TargetMachine
> tm
,
68 std::shared_ptr
<MCJITMemoryManager
> MemMgr
,
69 std::shared_ptr
<LegacyJITSymbolResolver
> Resolver
);
71 typedef llvm::SmallPtrSet
<Module
*, 4> ModulePtrSet
;
73 class OwningModuleContainer
{
75 OwningModuleContainer() {
77 ~OwningModuleContainer() {
78 freeModulePtrSet(AddedModules
);
79 freeModulePtrSet(LoadedModules
);
80 freeModulePtrSet(FinalizedModules
);
83 ModulePtrSet::iterator
begin_added() { return AddedModules
.begin(); }
84 ModulePtrSet::iterator
end_added() { return AddedModules
.end(); }
85 iterator_range
<ModulePtrSet::iterator
> added() {
86 return make_range(begin_added(), end_added());
89 ModulePtrSet::iterator
begin_loaded() { return LoadedModules
.begin(); }
90 ModulePtrSet::iterator
end_loaded() { return LoadedModules
.end(); }
92 ModulePtrSet::iterator
begin_finalized() { return FinalizedModules
.begin(); }
93 ModulePtrSet::iterator
end_finalized() { return FinalizedModules
.end(); }
95 void addModule(std::unique_ptr
<Module
> M
) {
96 AddedModules
.insert(M
.release());
99 bool removeModule(Module
*M
) {
100 return AddedModules
.erase(M
) || LoadedModules
.erase(M
) ||
101 FinalizedModules
.erase(M
);
104 bool hasModuleBeenAddedButNotLoaded(Module
*M
) {
105 return AddedModules
.contains(M
);
108 bool hasModuleBeenLoaded(Module
*M
) {
109 // If the module is in either the "loaded" or "finalized" sections it
111 return LoadedModules
.contains(M
) || FinalizedModules
.contains(M
);
114 bool hasModuleBeenFinalized(Module
*M
) {
115 return FinalizedModules
.contains(M
);
118 bool ownsModule(Module
* M
) {
119 return AddedModules
.contains(M
) || LoadedModules
.contains(M
) ||
120 FinalizedModules
.contains(M
);
123 void markModuleAsLoaded(Module
*M
) {
124 // This checks against logic errors in the MCJIT implementation.
125 // This function should never be called with either a Module that MCJIT
126 // does not own or a Module that has already been loaded and/or finalized.
127 assert(AddedModules
.count(M
) &&
128 "markModuleAsLoaded: Module not found in AddedModules");
130 // Remove the module from the "Added" set.
131 AddedModules
.erase(M
);
133 // Add the Module to the "Loaded" set.
134 LoadedModules
.insert(M
);
137 void markModuleAsFinalized(Module
*M
) {
138 // This checks against logic errors in the MCJIT implementation.
139 // This function should never be called with either a Module that MCJIT
140 // does not own, a Module that has not been loaded or a Module that has
141 // already been finalized.
142 assert(LoadedModules
.count(M
) &&
143 "markModuleAsFinalized: Module not found in LoadedModules");
145 // Remove the module from the "Loaded" section of the list.
146 LoadedModules
.erase(M
);
148 // Add the Module to the "Finalized" section of the list by inserting it
149 // before the 'end' iterator.
150 FinalizedModules
.insert(M
);
153 void markAllLoadedModulesAsFinalized() {
154 for (ModulePtrSet::iterator I
= LoadedModules
.begin(),
155 E
= LoadedModules
.end();
158 FinalizedModules
.insert(M
);
160 LoadedModules
.clear();
164 ModulePtrSet AddedModules
;
165 ModulePtrSet LoadedModules
;
166 ModulePtrSet FinalizedModules
;
168 void freeModulePtrSet(ModulePtrSet
& MPS
) {
169 // Go through the module set and delete everything.
170 for (ModulePtrSet::iterator I
= MPS
.begin(), E
= MPS
.end(); I
!= E
; ++I
) {
178 std::unique_ptr
<TargetMachine
> TM
;
180 std::shared_ptr
<MCJITMemoryManager
> MemMgr
;
181 LinkingSymbolResolver Resolver
;
183 std::vector
<JITEventListener
*> EventListeners
;
185 OwningModuleContainer OwnedModules
;
187 SmallVector
<object::OwningBinary
<object::Archive
>, 2> Archives
;
188 SmallVector
<std::unique_ptr
<MemoryBuffer
>, 2> Buffers
;
190 SmallVector
<std::unique_ptr
<object::ObjectFile
>, 2> LoadedObjects
;
192 // An optional ObjectCache to be notified of compiled objects and used to
193 // perform lookup of pre-compiled code to avoid re-compilation.
194 ObjectCache
*ObjCache
;
196 Function
*FindFunctionNamedInModulePtrSet(StringRef FnName
,
197 ModulePtrSet::iterator I
,
198 ModulePtrSet::iterator E
);
200 GlobalVariable
*FindGlobalVariableNamedInModulePtrSet(StringRef Name
,
202 ModulePtrSet::iterator I
,
203 ModulePtrSet::iterator E
);
205 void runStaticConstructorsDestructorsInModulePtrSet(bool isDtors
,
206 ModulePtrSet::iterator I
,
207 ModulePtrSet::iterator E
);
212 /// @name ExecutionEngine interface implementation
214 void addModule(std::unique_ptr
<Module
> M
) override
;
215 void addObjectFile(std::unique_ptr
<object::ObjectFile
> O
) override
;
216 void addObjectFile(object::OwningBinary
<object::ObjectFile
> O
) override
;
217 void addArchive(object::OwningBinary
<object::Archive
> O
) override
;
218 bool removeModule(Module
*M
) override
;
220 /// FindFunctionNamed - Search all of the active modules to find the function that
221 /// defines FnName. This is very slow operation and shouldn't be used for
223 Function
*FindFunctionNamed(StringRef FnName
) override
;
225 /// FindGlobalVariableNamed - Search all of the active modules to find the
226 /// global variable that defines Name. This is very slow operation and
227 /// shouldn't be used for general code.
228 GlobalVariable
*FindGlobalVariableNamed(StringRef Name
,
229 bool AllowInternal
= false) override
;
231 /// Sets the object manager that MCJIT should use to avoid compilation.
232 void setObjectCache(ObjectCache
*manager
) override
;
234 void setProcessAllSections(bool ProcessAllSections
) override
{
235 Dyld
.setProcessAllSections(ProcessAllSections
);
238 void generateCodeForModule(Module
*M
) override
;
240 /// finalizeObject - ensure the module is fully processed and is usable.
242 /// It is the user-level function for completing the process of making the
243 /// object usable for execution. It should be called after sections within an
244 /// object have been relocated using mapSectionAddress. When this method is
245 /// called the MCJIT execution engine will reapply relocations for a loaded
247 /// Is it OK to finalize a set of modules, add modules and finalize again.
248 // FIXME: Do we really need both of these?
249 void finalizeObject() override
;
250 virtual void finalizeModule(Module
*);
251 void finalizeLoadedModules();
253 /// runStaticConstructorsDestructors - This method is used to execute all of
254 /// the static constructors or destructors for a program.
256 /// \param isDtors - Run the destructors instead of constructors.
257 void runStaticConstructorsDestructors(bool isDtors
) override
;
259 void *getPointerToFunction(Function
*F
) override
;
261 GenericValue
runFunction(Function
*F
,
262 ArrayRef
<GenericValue
> ArgValues
) override
;
264 /// getPointerToNamedFunction - This method returns the address of the
265 /// specified function by using the dlsym function call. As such it is only
266 /// useful for resolving library symbols, not code generated symbols.
268 /// If AbortOnFailure is false and no function with the given name is
269 /// found, this function silently returns a null pointer. Otherwise,
270 /// it prints a message to stderr and aborts.
272 void *getPointerToNamedFunction(StringRef Name
,
273 bool AbortOnFailure
= true) override
;
275 /// mapSectionAddress - map a section to its target address space value.
276 /// Map the address of a JIT section as returned from the memory manager
277 /// to the address in the target process as the running code will see it.
278 /// This is the address which will be used for relocation resolution.
279 void mapSectionAddress(const void *LocalAddress
,
280 uint64_t TargetAddress
) override
{
281 Dyld
.mapSectionAddress(LocalAddress
, TargetAddress
);
283 void RegisterJITEventListener(JITEventListener
*L
) override
;
284 void UnregisterJITEventListener(JITEventListener
*L
) override
;
286 // If successful, these function will implicitly finalize all loaded objects.
287 // To get a function address within MCJIT without causing a finalize, use
289 uint64_t getGlobalValueAddress(const std::string
&Name
) override
;
290 uint64_t getFunctionAddress(const std::string
&Name
) override
;
292 TargetMachine
*getTargetMachine() override
{ return TM
.get(); }
295 /// @name (Private) Registration Interfaces
298 static void Register() {
299 MCJITCtor
= createJIT
;
302 static ExecutionEngine
*
303 createJIT(std::unique_ptr
<Module
> M
, std::string
*ErrorStr
,
304 std::shared_ptr
<MCJITMemoryManager
> MemMgr
,
305 std::shared_ptr
<LegacyJITSymbolResolver
> Resolver
,
306 std::unique_ptr
<TargetMachine
> TM
);
310 // Takes a mangled name and returns the corresponding JITSymbol (if a
311 // definition of that mangled name has been added to the JIT).
312 JITSymbol
findSymbol(const std::string
&Name
, bool CheckFunctionsOnly
);
314 // DEPRECATED - Please use findSymbol instead.
316 // This is not directly exposed via the ExecutionEngine API, but it is
317 // used by the LinkingMemoryManager.
319 // getSymbolAddress takes an unmangled name and returns the corresponding
320 // JITSymbol if a definition of the name has been added to the JIT.
321 uint64_t getSymbolAddress(const std::string
&Name
,
322 bool CheckFunctionsOnly
);
325 /// emitObject -- Generate a JITed object in memory from the specified module
326 /// Currently, MCJIT only supports a single module and the module passed to
327 /// this function call is expected to be the contained module. The module
328 /// is passed as a parameter here to prepare for multiple module support in
330 std::unique_ptr
<MemoryBuffer
> emitObject(Module
*M
);
332 void notifyObjectLoaded(const object::ObjectFile
&Obj
,
333 const RuntimeDyld::LoadedObjectInfo
&L
);
334 void notifyFreeingObject(const object::ObjectFile
&Obj
);
336 JITSymbol
findExistingSymbol(const std::string
&Name
);
337 Module
*findModuleForSymbol(const std::string
&Name
, bool CheckFunctionsOnly
);
340 } // end llvm namespace
342 #endif // LLVM_LIB_EXECUTIONENGINE_MCJIT_MCJIT_H