1 //===- ExecutionEngine.h - Abstract Execution Engine Interface --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the abstract interface that implements execution support
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_EXECUTIONENGINE_EXECUTIONENGINE_H
16 #define LLVM_EXECUTIONENGINE_EXECUTIONENGINE_H
18 #include "llvm-c/ExecutionEngine.h"
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/IR/Module.h"
22 #include "llvm/IR/ValueHandle.h"
23 #include "llvm/IR/ValueMap.h"
24 #include "llvm/MC/MCCodeGenInfo.h"
25 #include "llvm/Object/Binary.h"
26 #include "llvm/Support/ErrorHandling.h"
27 #include "llvm/Support/Mutex.h"
28 #include "llvm/Target/TargetMachine.h"
29 #include "llvm/Target/TargetOptions.h"
39 class ExecutionEngine;
43 class JITEventListener;
44 class MachineCodeInfo;
47 class RTDyldMemoryManager;
56 /// \brief Helper class for helping synchronize access to the global address map
57 /// table. Access to this class should be serialized under a mutex.
58 class ExecutionEngineState {
60 struct AddressMapConfig : public ValueMapConfig<const GlobalValue*> {
61 typedef ExecutionEngineState *ExtraData;
62 static sys::Mutex *getMutex(ExecutionEngineState *EES);
63 static void onDelete(ExecutionEngineState *EES, const GlobalValue *Old);
64 static void onRAUW(ExecutionEngineState *, const GlobalValue *,
68 typedef ValueMap<const GlobalValue *, void *, AddressMapConfig>
74 /// GlobalAddressMap - A mapping between LLVM global values and their
75 /// actualized version...
76 GlobalAddressMapTy GlobalAddressMap;
78 /// GlobalAddressReverseMap - This is the reverse mapping of GlobalAddressMap,
79 /// used to convert raw addresses into the LLVM global value that is emitted
80 /// at the address. This map is not computed unless getGlobalValueAtAddress
81 /// is called at some point.
82 std::map<void *, AssertingVH<const GlobalValue> > GlobalAddressReverseMap;
85 ExecutionEngineState(ExecutionEngine &EE);
87 GlobalAddressMapTy &getGlobalAddressMap() {
88 return GlobalAddressMap;
91 std::map<void*, AssertingVH<const GlobalValue> > &
92 getGlobalAddressReverseMap() {
93 return GlobalAddressReverseMap;
96 /// \brief Erase an entry from the mapping table.
98 /// \returns The address that \p ToUnmap was happed to.
99 void *RemoveMapping(const GlobalValue *ToUnmap);
102 /// \brief Abstract interface for implementation execution of LLVM modules,
103 /// designed to support both interpreter and just-in-time (JIT) compiler
105 class ExecutionEngine {
106 /// The state object holding the global address mapping, which must be
107 /// accessed synchronously.
109 // FIXME: There is no particular need the entire map needs to be
110 // synchronized. Wouldn't a reader-writer design be better here?
111 ExecutionEngineState EEState;
113 /// The target data for the platform for which execution is being performed.
114 const DataLayout *DL;
116 /// Whether lazy JIT compilation is enabled.
117 bool CompilingLazily;
119 /// Whether JIT compilation of external global variables is allowed.
120 bool GVCompilationDisabled;
122 /// Whether the JIT should perform lookups of external symbols (e.g.,
124 bool SymbolSearchingDisabled;
126 /// Whether the JIT should verify IR modules during compilation.
129 friend class EngineBuilder; // To allow access to JITCtor and InterpCtor.
132 /// The list of Modules that we are JIT'ing from. We use a SmallVector to
133 /// optimize for the case where there is only one module.
134 SmallVector<std::unique_ptr<Module>, 1> Modules;
136 void setDataLayout(const DataLayout *Val) { DL = Val; }
138 /// getMemoryforGV - Allocate memory for a global variable.
139 virtual char *getMemoryForGV(const GlobalVariable *GV);
141 static ExecutionEngine *(*MCJITCtor)(
142 std::unique_ptr<Module> M,
143 std::string *ErrorStr,
144 std::unique_ptr<RTDyldMemoryManager> MCJMM,
145 std::unique_ptr<TargetMachine> TM);
147 static ExecutionEngine *(*OrcMCJITReplacementCtor)(
148 std::string *ErrorStr,
149 std::unique_ptr<RTDyldMemoryManager> OrcJMM,
150 std::unique_ptr<TargetMachine> TM);
152 static ExecutionEngine *(*InterpCtor)(std::unique_ptr<Module> M,
153 std::string *ErrorStr);
155 /// LazyFunctionCreator - If an unknown function is needed, this function
156 /// pointer is invoked to create it. If this returns null, the JIT will
158 void *(*LazyFunctionCreator)(const std::string &);
161 /// lock - This lock protects the ExecutionEngine and MCJIT classes. It must
162 /// be held while changing the internal state of any of those classes.
165 //===--------------------------------------------------------------------===//
166 // ExecutionEngine Startup
167 //===--------------------------------------------------------------------===//
169 virtual ~ExecutionEngine();
171 /// Add a Module to the list of modules that we can JIT from.
172 virtual void addModule(std::unique_ptr<Module> M) {
173 Modules.push_back(std::move(M));
176 /// addObjectFile - Add an ObjectFile to the execution engine.
178 /// This method is only supported by MCJIT. MCJIT will immediately load the
179 /// object into memory and adds its symbols to the list used to resolve
180 /// external symbols while preparing other objects for execution.
182 /// Objects added using this function will not be made executable until
183 /// needed by another object.
185 /// MCJIT will take ownership of the ObjectFile.
186 virtual void addObjectFile(std::unique_ptr<object::ObjectFile> O);
187 virtual void addObjectFile(object::OwningBinary<object::ObjectFile> O);
189 /// addArchive - Add an Archive to the execution engine.
191 /// This method is only supported by MCJIT. MCJIT will use the archive to
192 /// resolve external symbols in objects it is loading. If a symbol is found
193 /// in the Archive the contained object file will be extracted (in memory)
194 /// and loaded for possible execution.
195 virtual void addArchive(object::OwningBinary<object::Archive> A);
197 //===--------------------------------------------------------------------===//
199 const DataLayout *getDataLayout() const { return DL; }
201 /// removeModule - Remove a Module from the list of modules. Returns true if
203 virtual bool removeModule(Module *M);
205 /// FindFunctionNamed - Search all of the active modules to find the one that
206 /// defines FnName. This is very slow operation and shouldn't be used for
208 virtual Function *FindFunctionNamed(const char *FnName);
210 /// runFunction - Execute the specified function with the specified arguments,
211 /// and return the result.
212 virtual GenericValue runFunction(Function *F,
213 const std::vector<GenericValue> &ArgValues) = 0;
215 /// getPointerToNamedFunction - This method returns the address of the
216 /// specified function by using the dlsym function call. As such it is only
217 /// useful for resolving library symbols, not code generated symbols.
219 /// If AbortOnFailure is false and no function with the given name is
220 /// found, this function silently returns a null pointer. Otherwise,
221 /// it prints a message to stderr and aborts.
223 /// This function is deprecated for the MCJIT execution engine.
224 virtual void *getPointerToNamedFunction(StringRef Name,
225 bool AbortOnFailure = true) = 0;
227 /// mapSectionAddress - map a section to its target address space value.
228 /// Map the address of a JIT section as returned from the memory manager
229 /// to the address in the target process as the running code will see it.
230 /// This is the address which will be used for relocation resolution.
231 virtual void mapSectionAddress(const void *LocalAddress, uint64_t TargetAddress) {
232 llvm_unreachable("Re-mapping of section addresses not supported with this "
236 /// generateCodeForModule - Run code generation for the specified module and
237 /// load it into memory.
239 /// When this function has completed, all code and data for the specified
240 /// module, and any module on which this module depends, will be generated
241 /// and loaded into memory, but relocations will not yet have been applied
242 /// and all memory will be readable and writable but not executable.
244 /// This function is primarily useful when generating code for an external
245 /// target, allowing the client an opportunity to remap section addresses
246 /// before relocations are applied. Clients that intend to execute code
247 /// locally can use the getFunctionAddress call, which will generate code
248 /// and apply final preparations all in one step.
250 /// This method has no effect for the interpeter.
251 virtual void generateCodeForModule(Module *M) {}
253 /// finalizeObject - ensure the module is fully processed and is usable.
255 /// It is the user-level function for completing the process of making the
256 /// object usable for execution. It should be called after sections within an
257 /// object have been relocated using mapSectionAddress. When this method is
258 /// called the MCJIT execution engine will reapply relocations for a loaded
259 /// object. This method has no effect for the interpeter.
260 virtual void finalizeObject() {}
262 /// runStaticConstructorsDestructors - This method is used to execute all of
263 /// the static constructors or destructors for a program.
265 /// \param isDtors - Run the destructors instead of constructors.
266 virtual void runStaticConstructorsDestructors(bool isDtors);
268 /// This method is used to execute all of the static constructors or
269 /// destructors for a particular module.
271 /// \param isDtors - Run the destructors instead of constructors.
272 void runStaticConstructorsDestructors(Module &module, bool isDtors);
275 /// runFunctionAsMain - This is a helper function which wraps runFunction to
276 /// handle the common task of starting up main with the specified argc, argv,
277 /// and envp parameters.
278 int runFunctionAsMain(Function *Fn, const std::vector<std::string> &argv,
279 const char * const * envp);
282 /// addGlobalMapping - Tell the execution engine that the specified global is
283 /// at the specified location. This is used internally as functions are JIT'd
284 /// and as global variables are laid out in memory. It can and should also be
285 /// used by clients of the EE that want to have an LLVM global overlay
286 /// existing data in memory. Mappings are automatically removed when their
287 /// GlobalValue is destroyed.
288 void addGlobalMapping(const GlobalValue *GV, void *Addr);
290 /// clearAllGlobalMappings - Clear all global mappings and start over again,
291 /// for use in dynamic compilation scenarios to move globals.
292 void clearAllGlobalMappings();
294 /// clearGlobalMappingsFromModule - Clear all global mappings that came from a
295 /// particular module, because it has been removed from the JIT.
296 void clearGlobalMappingsFromModule(Module *M);
298 /// updateGlobalMapping - Replace an existing mapping for GV with a new
299 /// address. This updates both maps as required. If "Addr" is null, the
300 /// entry for the global is removed from the mappings. This returns the old
301 /// value of the pointer, or null if it was not in the map.
302 void *updateGlobalMapping(const GlobalValue *GV, void *Addr);
304 /// getPointerToGlobalIfAvailable - This returns the address of the specified
305 /// global value if it is has already been codegen'd, otherwise it returns
308 /// This function is deprecated for the MCJIT execution engine. It doesn't
309 /// seem to be needed in that case, but an equivalent can be added if it is.
310 void *getPointerToGlobalIfAvailable(const GlobalValue *GV);
312 /// getPointerToGlobal - This returns the address of the specified global
313 /// value. This may involve code generation if it's a function.
315 /// This function is deprecated for the MCJIT execution engine. Use
316 /// getGlobalValueAddress instead.
317 void *getPointerToGlobal(const GlobalValue *GV);
319 /// getPointerToFunction - The different EE's represent function bodies in
320 /// different ways. They should each implement this to say what a function
321 /// pointer should look like. When F is destroyed, the ExecutionEngine will
322 /// remove its global mapping and free any machine code. Be sure no threads
323 /// are running inside F when that happens.
325 /// This function is deprecated for the MCJIT execution engine. Use
326 /// getFunctionAddress instead.
327 virtual void *getPointerToFunction(Function *F) = 0;
329 /// getPointerToFunctionOrStub - If the specified function has been
330 /// code-gen'd, return a pointer to the function. If not, compile it, or use
331 /// a stub to implement lazy compilation if available. See
332 /// getPointerToFunction for the requirements on destroying F.
334 /// This function is deprecated for the MCJIT execution engine. Use
335 /// getFunctionAddress instead.
336 virtual void *getPointerToFunctionOrStub(Function *F) {
337 // Default implementation, just codegen the function.
338 return getPointerToFunction(F);
341 /// getGlobalValueAddress - Return the address of the specified global
342 /// value. This may involve code generation.
344 /// This function should not be called with the interpreter engine.
345 virtual uint64_t getGlobalValueAddress(const std::string &Name) {
346 // Default implementation for the interpreter. MCJIT will override this.
347 // JIT and interpreter clients should use getPointerToGlobal instead.
351 /// getFunctionAddress - Return the address of the specified function.
352 /// This may involve code generation.
353 virtual uint64_t getFunctionAddress(const std::string &Name) {
354 // Default implementation for the interpreter. MCJIT will override this.
355 // Interpreter clients should use getPointerToFunction instead.
359 /// getGlobalValueAtAddress - Return the LLVM global value object that starts
360 /// at the specified address.
362 const GlobalValue *getGlobalValueAtAddress(void *Addr);
364 /// StoreValueToMemory - Stores the data in Val of type Ty at address Ptr.
365 /// Ptr is the address of the memory at which to store Val, cast to
366 /// GenericValue *. It is not a pointer to a GenericValue containing the
367 /// address at which to store Val.
368 void StoreValueToMemory(const GenericValue &Val, GenericValue *Ptr,
371 void InitializeMemory(const Constant *Init, void *Addr);
373 /// getOrEmitGlobalVariable - Return the address of the specified global
374 /// variable, possibly emitting it to memory if needed. This is used by the
377 /// This function is deprecated for the MCJIT execution engine. Use
378 /// getGlobalValueAddress instead.
379 virtual void *getOrEmitGlobalVariable(const GlobalVariable *GV) {
380 return getPointerToGlobal((const GlobalValue *)GV);
383 /// Registers a listener to be called back on various events within
384 /// the JIT. See JITEventListener.h for more details. Does not
385 /// take ownership of the argument. The argument may be NULL, in
386 /// which case these functions do nothing.
387 virtual void RegisterJITEventListener(JITEventListener *) {}
388 virtual void UnregisterJITEventListener(JITEventListener *) {}
390 /// Sets the pre-compiled object cache. The ownership of the ObjectCache is
391 /// not changed. Supported by MCJIT but not the interpreter.
392 virtual void setObjectCache(ObjectCache *) {
393 llvm_unreachable("No support for an object cache");
396 /// setProcessAllSections (MCJIT Only): By default, only sections that are
397 /// "required for execution" are passed to the RTDyldMemoryManager, and other
398 /// sections are discarded. Passing 'true' to this method will cause
399 /// RuntimeDyld to pass all sections to its RTDyldMemoryManager regardless
400 /// of whether they are "required to execute" in the usual sense.
402 /// Rationale: Some MCJIT clients want to be able to inspect metadata
403 /// sections (e.g. Dwarf, Stack-maps) to enable functionality or analyze
404 /// performance. Passing these sections to the memory manager allows the
405 /// client to make policy about the relevant sections, rather than having
407 virtual void setProcessAllSections(bool ProcessAllSections) {
408 llvm_unreachable("No support for ProcessAllSections option");
411 /// Return the target machine (if available).
412 virtual TargetMachine *getTargetMachine() { return nullptr; }
414 /// DisableLazyCompilation - When lazy compilation is off (the default), the
415 /// JIT will eagerly compile every function reachable from the argument to
416 /// getPointerToFunction. If lazy compilation is turned on, the JIT will only
417 /// compile the one function and emit stubs to compile the rest when they're
418 /// first called. If lazy compilation is turned off again while some lazy
419 /// stubs are still around, and one of those stubs is called, the program will
422 /// In order to safely compile lazily in a threaded program, the user must
423 /// ensure that 1) only one thread at a time can call any particular lazy
424 /// stub, and 2) any thread modifying LLVM IR must hold the JIT's lock
425 /// (ExecutionEngine::lock) or otherwise ensure that no other thread calls a
426 /// lazy stub. See http://llvm.org/PR5184 for details.
427 void DisableLazyCompilation(bool Disabled = true) {
428 CompilingLazily = !Disabled;
430 bool isCompilingLazily() const {
431 return CompilingLazily;
434 /// DisableGVCompilation - If called, the JIT will abort if it's asked to
435 /// allocate space and populate a GlobalVariable that is not internal to
437 void DisableGVCompilation(bool Disabled = true) {
438 GVCompilationDisabled = Disabled;
440 bool isGVCompilationDisabled() const {
441 return GVCompilationDisabled;
444 /// DisableSymbolSearching - If called, the JIT will not try to lookup unknown
445 /// symbols with dlsym. A client can still use InstallLazyFunctionCreator to
446 /// resolve symbols in a custom way.
447 void DisableSymbolSearching(bool Disabled = true) {
448 SymbolSearchingDisabled = Disabled;
450 bool isSymbolSearchingDisabled() const {
451 return SymbolSearchingDisabled;
454 /// Enable/Disable IR module verification.
456 /// Note: Module verification is enabled by default in Debug builds, and
457 /// disabled by default in Release. Use this method to override the default.
458 void setVerifyModules(bool Verify) {
459 VerifyModules = Verify;
461 bool getVerifyModules() const {
462 return VerifyModules;
465 /// InstallLazyFunctionCreator - If an unknown function is needed, the
466 /// specified function pointer is invoked to create it. If it returns null,
467 /// the JIT will abort.
468 void InstallLazyFunctionCreator(void* (*P)(const std::string &)) {
469 LazyFunctionCreator = P;
473 ExecutionEngine() : EEState(*this) {}
474 explicit ExecutionEngine(std::unique_ptr<Module> M);
478 void EmitGlobalVariable(const GlobalVariable *GV);
480 GenericValue getConstantValue(const Constant *C);
481 void LoadValueFromMemory(GenericValue &Result, GenericValue *Ptr,
485 namespace EngineKind {
486 // These are actually bitmasks that get or-ed together.
491 const static Kind Either = (Kind)(JIT | Interpreter);
494 /// Builder class for ExecutionEngines. Use this by stack-allocating a builder,
495 /// chaining the various set* methods, and terminating it with a .create()
497 class EngineBuilder {
499 std::unique_ptr<Module> M;
500 EngineKind::Kind WhichEngine;
501 std::string *ErrorStr;
502 CodeGenOpt::Level OptLevel;
503 std::unique_ptr<RTDyldMemoryManager> MCJMM;
504 TargetOptions Options;
505 Reloc::Model RelocModel;
506 CodeModel::Model CMModel;
509 SmallVector<std::string, 4> MAttrs;
511 bool UseOrcMCJITReplacement;
514 /// Default constructor for EngineBuilder.
517 /// Constructor for EngineBuilder.
518 EngineBuilder(std::unique_ptr<Module> M);
520 // Out-of-line since we don't have the def'n of RTDyldMemoryManager here.
523 /// setEngineKind - Controls whether the user wants the interpreter, the JIT,
524 /// or whichever engine works. This option defaults to EngineKind::Either.
525 EngineBuilder &setEngineKind(EngineKind::Kind w) {
530 /// setMCJITMemoryManager - Sets the MCJIT memory manager to use. This allows
531 /// clients to customize their memory allocation policies for the MCJIT. This
532 /// is only appropriate for the MCJIT; setting this and configuring the builder
533 /// to create anything other than MCJIT will cause a runtime error. If create()
534 /// is called and is successful, the created engine takes ownership of the
535 /// memory manager. This option defaults to NULL.
536 EngineBuilder &setMCJITMemoryManager(std::unique_ptr<RTDyldMemoryManager> mcjmm);
538 /// setErrorStr - Set the error string to write to on error. This option
539 /// defaults to NULL.
540 EngineBuilder &setErrorStr(std::string *e) {
545 /// setOptLevel - Set the optimization level for the JIT. This option
546 /// defaults to CodeGenOpt::Default.
547 EngineBuilder &setOptLevel(CodeGenOpt::Level l) {
552 /// setTargetOptions - Set the target options that the ExecutionEngine
553 /// target is using. Defaults to TargetOptions().
554 EngineBuilder &setTargetOptions(const TargetOptions &Opts) {
559 /// setRelocationModel - Set the relocation model that the ExecutionEngine
560 /// target is using. Defaults to target specific default "Reloc::Default".
561 EngineBuilder &setRelocationModel(Reloc::Model RM) {
566 /// setCodeModel - Set the CodeModel that the ExecutionEngine target
567 /// data is using. Defaults to target specific default
568 /// "CodeModel::JITDefault".
569 EngineBuilder &setCodeModel(CodeModel::Model M) {
574 /// setMArch - Override the architecture set by the Module's triple.
575 EngineBuilder &setMArch(StringRef march) {
576 MArch.assign(march.begin(), march.end());
580 /// setMCPU - Target a specific cpu type.
581 EngineBuilder &setMCPU(StringRef mcpu) {
582 MCPU.assign(mcpu.begin(), mcpu.end());
586 /// setVerifyModules - Set whether the JIT implementation should verify
587 /// IR modules during compilation.
588 EngineBuilder &setVerifyModules(bool Verify) {
589 VerifyModules = Verify;
593 /// setMAttrs - Set cpu-specific attributes.
594 template<typename StringSequence>
595 EngineBuilder &setMAttrs(const StringSequence &mattrs) {
597 MAttrs.append(mattrs.begin(), mattrs.end());
601 // \brief Use OrcMCJITReplacement instead of MCJIT. Off by default.
602 void setUseOrcMCJITReplacement(bool UseOrcMCJITReplacement) {
603 this->UseOrcMCJITReplacement = UseOrcMCJITReplacement;
606 TargetMachine *selectTarget();
608 /// selectTarget - Pick a target either via -march or by guessing the native
609 /// arch. Add any CPU features specified via -mcpu or -mattr.
610 TargetMachine *selectTarget(const Triple &TargetTriple,
613 const SmallVectorImpl<std::string>& MAttrs);
615 ExecutionEngine *create() {
616 return create(selectTarget());
619 ExecutionEngine *create(TargetMachine *TM);
622 // Create wrappers for C Binding types (see CBindingWrapping.h).
623 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(ExecutionEngine, LLVMExecutionEngineRef)
625 } // End llvm namespace