//===- ExecutionEngine.h - Abstract Execution Engine Interface --*- C++ -*-===//
//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
// This file defines the abstract interface that implements execution support
// for LLVM.
//
//===----------------------------------------------------------------------===//
-#ifndef EXECUTION_ENGINE_H
-#define EXECUTION_ENGINE_H
+#ifndef LLVM_EXECUTION_ENGINE_H
+#define LLVM_EXECUTION_ENGINE_H
#include <vector>
-#include <string>
#include <map>
-#include <cassert>
+#include <string>
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/ValueMap.h"
+#include "llvm/Support/ValueHandle.h"
+#include "llvm/System/Mutex.h"
+#include "llvm/Target/TargetMachine.h"
+
+namespace llvm {
+
+struct GenericValue;
class Constant;
-class Type;
-class GlobalValue;
+class ExecutionEngine;
class Function;
+class GlobalVariable;
+class GlobalValue;
+class JITEventListener;
+class JITMemoryManager;
+class MachineCodeInfo;
class Module;
+class MutexGuard;
class TargetData;
-union GenericValue;
+class Type;
+
+class ExecutionEngineState {
+public:
+ struct AddressMapConfig : public ValueMapConfig<const GlobalValue*> {
+ typedef ExecutionEngineState *ExtraData;
+ static sys::Mutex *getMutex(ExecutionEngineState *EES);
+ static void onDelete(ExecutionEngineState *EES, const GlobalValue *Old);
+ static void onRAUW(ExecutionEngineState *, const GlobalValue *,
+ const GlobalValue *);
+ };
+
+ typedef ValueMap<const GlobalValue *, void *, AddressMapConfig>
+ GlobalAddressMapTy;
+
+private:
+ ExecutionEngine &EE;
+
+ /// GlobalAddressMap - A mapping between LLVM global values and their
+ /// actualized version...
+ GlobalAddressMapTy GlobalAddressMap;
+
+ /// GlobalAddressReverseMap - This is the reverse mapping of GlobalAddressMap,
+ /// used to convert raw addresses into the LLVM global value that is emitted
+ /// at the address. This map is not computed unless getGlobalValueAtAddress
+ /// is called at some point.
+ std::map<void *, AssertingVH<const GlobalValue> > GlobalAddressReverseMap;
+
+public:
+ ExecutionEngineState(ExecutionEngine &EE);
+
+ GlobalAddressMapTy &
+ getGlobalAddressMap(const MutexGuard &) {
+ return GlobalAddressMap;
+ }
+
+ std::map<void*, AssertingVH<const GlobalValue> > &
+ getGlobalAddressReverseMap(const MutexGuard &) {
+ return GlobalAddressReverseMap;
+ }
+
+ // Returns the address ToUnmap was mapped to.
+ void *RemoveMapping(const MutexGuard &, const GlobalValue *ToUnmap);
+};
+
class ExecutionEngine {
- Module &CurMod;
const TargetData *TD;
+ ExecutionEngineState EEState;
+ bool CompilingLazily;
+ bool GVCompilationDisabled;
+ bool SymbolSearchingDisabled;
-protected:
- // GlobalAddress - A mapping between LLVM global values and their actualized
- // version...
- std::map<const GlobalValue*, void *> GlobalAddress;
+ friend class EngineBuilder; // To allow access to JITCtor and InterpCtor.
- void setTargetData(const TargetData &td) {
- TD = &td;
+protected:
+ /// Modules - This is a list of Modules that we are JIT'ing from. We use a
+ /// smallvector to optimize for the case where there is only one module.
+ SmallVector<Module*, 1> Modules;
+
+ void setTargetData(const TargetData *td) {
+ TD = td;
}
+
+ /// getMemoryforGV - Allocate memory for a global variable.
+ virtual char* getMemoryForGV(const GlobalVariable* GV);
+
+ // To avoid having libexecutionengine depend on the JIT and interpreter
+ // libraries, the JIT and Interpreter set these functions to ctor pointers
+ // at startup time if they are linked in.
+ static ExecutionEngine *(*JITCtor)(
+ Module *M,
+ std::string *ErrorStr,
+ JITMemoryManager *JMM,
+ CodeGenOpt::Level OptLevel,
+ bool GVsWithCode,
+ CodeModel::Model CMM,
+ StringRef MArch,
+ StringRef MCPU,
+ const SmallVectorImpl<std::string>& MAttrs);
+ static ExecutionEngine *(*InterpCtor)(Module *M,
+ std::string *ErrorStr);
+
+ /// LazyFunctionCreator - If an unknown function is needed, this function
+ /// pointer is invoked to create it. If this returns null, the JIT will abort.
+ void* (*LazyFunctionCreator)(const std::string &);
+
+ /// ExceptionTableRegister - If Exception Handling is set, the JIT will
+ /// register dwarf tables with this function.
+ typedef void (*EERegisterFn)(void*);
+ EERegisterFn ExceptionTableRegister;
+ EERegisterFn ExceptionTableDeregister;
+ std::vector<void*> AllExceptionTables;
+
public:
- ExecutionEngine(Module *M) : CurMod(*M) {
- assert(M && "Module is null?");
- }
+ /// lock - This lock is protects the ExecutionEngine, JIT, JITResolver and
+ /// JITEmitter classes. It must be held while changing the internal state of
+ /// any of those classes.
+ sys::Mutex lock; // Used to make this class and subclasses thread-safe
+
+ //===--------------------------------------------------------------------===//
+ // ExecutionEngine Startup
+ //===--------------------------------------------------------------------===//
+
virtual ~ExecutionEngine();
+
+ /// create - This is the factory method for creating an execution engine which
+ /// is appropriate for the current machine. This takes ownership of the
+ /// module.
+ static ExecutionEngine *create(Module *M,
+ bool ForceInterpreter = false,
+ std::string *ErrorStr = 0,
+ CodeGenOpt::Level OptLevel =
+ CodeGenOpt::Default,
+ // Allocating globals with code breaks
+ // freeMachineCodeForFunction and is probably
+ // unsafe and bad for performance. However,
+ // we have clients who depend on this
+ // behavior, so we must support it.
+ // Eventually, when we're willing to break
+ // some backwards compatability, this flag
+ // should be flipped to false, so that by
+ // default freeMachineCodeForFunction works.
+ bool GVsWithCode = true);
+
+ /// createJIT - This is the factory method for creating a JIT for the current
+ /// machine, it does not fall back to the interpreter. This takes ownership
+ /// of the Module and JITMemoryManager if successful.
+ ///
+ /// Clients should make sure to initialize targets prior to calling this
+ /// function.
+ static ExecutionEngine *createJIT(Module *M,
+ std::string *ErrorStr = 0,
+ JITMemoryManager *JMM = 0,
+ CodeGenOpt::Level OptLevel =
+ CodeGenOpt::Default,
+ bool GVsWithCode = true,
+ CodeModel::Model CMM =
+ CodeModel::Default);
+
+ /// addModule - Add a Module to the list of modules that we can JIT from.
+ /// Note that this takes ownership of the Module: when the ExecutionEngine is
+ /// destroyed, it destroys the Module as well.
+ virtual void addModule(Module *M) {
+ Modules.push_back(M);
+ }
+
+ //===----------------------------------------------------------------------===//
+
+ const TargetData *getTargetData() const { return TD; }
+
+
+ /// removeModule - Remove a Module from the list of modules. Returns true if
+ /// M is found.
+ virtual bool removeModule(Module *M);
+
+ /// FindFunctionNamed - Search all of the active modules to find the one that
+ /// defines FnName. This is very slow operation and shouldn't be used for
+ /// general code.
+ Function *FindFunctionNamed(const char *FnName);
+
+ /// runFunction - Execute the specified function with the specified arguments,
+ /// and return the result.
+ ///
+ virtual GenericValue runFunction(Function *F,
+ const std::vector<GenericValue> &ArgValues) = 0;
+
+ /// runStaticConstructorsDestructors - This method is used to execute all of
+ /// the static constructors or destructors for a program, depending on the
+ /// value of isDtors.
+ void runStaticConstructorsDestructors(bool isDtors);
+ /// runStaticConstructorsDestructors - This method is used to execute all of
+ /// the static constructors or destructors for a module, depending on the
+ /// value of isDtors.
+ void runStaticConstructorsDestructors(Module *module, bool isDtors);
+
+
+ /// runFunctionAsMain - This is a helper function which wraps runFunction to
+ /// handle the common task of starting up main with the specified argc, argv,
+ /// and envp parameters.
+ int runFunctionAsMain(Function *Fn, const std::vector<std::string> &argv,
+ const char * const * envp);
+
+
+ /// addGlobalMapping - Tell the execution engine that the specified global is
+ /// at the specified location. This is used internally as functions are JIT'd
+ /// and as global variables are laid out in memory. It can and should also be
+ /// used by clients of the EE that want to have an LLVM global overlay
+ /// existing data in memory. Mappings are automatically removed when their
+ /// GlobalValue is destroyed.
+ void addGlobalMapping(const GlobalValue *GV, void *Addr);
+
+ /// clearAllGlobalMappings - Clear all global mappings and start over again
+ /// use in dynamic compilation scenarios when you want to move globals
+ void clearAllGlobalMappings();
+
+ /// clearGlobalMappingsFromModule - Clear all global mappings that came from a
+ /// particular module, because it has been removed from the JIT.
+ void clearGlobalMappingsFromModule(Module *M);
+
+ /// updateGlobalMapping - Replace an existing mapping for GV with a new
+ /// address. This updates both maps as required. If "Addr" is null, the
+ /// entry for the global is removed from the mappings. This returns the old
+ /// value of the pointer, or null if it was not in the map.
+ void *updateGlobalMapping(const GlobalValue *GV, void *Addr);
+
+ /// getPointerToGlobalIfAvailable - This returns the address of the specified
+ /// global value if it is has already been codegen'd, otherwise it returns
+ /// null.
+ ///
+ void *getPointerToGlobalIfAvailable(const GlobalValue *GV);
+
+ /// getPointerToGlobal - This returns the address of the specified global
+ /// value. This may involve code generation if it's a function.
+ ///
+ void *getPointerToGlobal(const GlobalValue *GV);
+
+ /// getPointerToFunction - The different EE's represent function bodies in
+ /// different ways. They should each implement this to say what a function
+ /// pointer should look like. When F is destroyed, the ExecutionEngine will
+ /// remove its global mapping and free any machine code. Be sure no threads
+ /// are running inside F when that happens.
+ ///
+ virtual void *getPointerToFunction(Function *F) = 0;
+
+ /// getPointerToBasicBlock - The different EE's represent basic blocks in
+ /// different ways. Return the representation for a blockaddress of the
+ /// specified block.
+ ///
+ virtual void *getPointerToBasicBlock(BasicBlock *BB) = 0;
- Module &getModule() const { return CurMod; }
- const TargetData &getTargetData() const { return *TD; }
+ /// getPointerToFunctionOrStub - If the specified function has been
+ /// code-gen'd, return a pointer to the function. If not, compile it, or use
+ /// a stub to implement lazy compilation if available. See
+ /// getPointerToFunction for the requirements on destroying F.
+ ///
+ virtual void *getPointerToFunctionOrStub(Function *F) {
+ // Default implementation, just codegen the function.
+ return getPointerToFunction(F);
+ }
- /// run - Start execution with the specified function, arguments, and
- /// environment.
+ // The JIT overrides a version that actually does this.
+ virtual void runJITOnFunction(Function *, MachineCodeInfo * = 0) { }
+
+ /// getGlobalValueAtAddress - Return the LLVM global value object that starts
+ /// at the specified address.
///
- virtual int run(const std::string &FnName,
- const std::vector<std::string> &Args,
- const char ** envp) = 0;
+ const GlobalValue *getGlobalValueAtAddress(void *Addr);
+
+
+ void StoreValueToMemory(const GenericValue &Val, GenericValue *Ptr,
+ const Type *Ty);
+ void InitializeMemory(const Constant *Init, void *Addr);
- /// createJIT - Create an return a new JIT compiler if there is one available
- /// for the current target. Otherwise it returns null.
+ /// recompileAndRelinkFunction - This method is used to force a function
+ /// which has already been compiled to be compiled again, possibly
+ /// after it has been modified. Then the entry to the old copy is overwritten
+ /// with a branch to the new copy. If there was no old copy, this acts
+ /// just like VM::getPointerToFunction().
///
- static ExecutionEngine *createJIT(Module *M, unsigned Config);
+ virtual void *recompileAndRelinkFunction(Function *F) = 0;
- /// createInterpreter - Create a new interpreter object. This can never fail.
+ /// freeMachineCodeForFunction - Release memory in the ExecutionEngine
+ /// corresponding to the machine code emitted to execute this function, useful
+ /// for garbage-collecting generated code.
///
- static ExecutionEngine *createInterpreter(Module *M, unsigned Config,
- bool DebugMode, bool TraceMode);
+ virtual void freeMachineCodeForFunction(Function *F) = 0;
- void addGlobalMapping(const Function *F, void *Addr) {
- void *&CurVal = GlobalAddress[(const GlobalValue*)F];
- assert(CurVal == 0 && "GlobalMapping already established!");
- CurVal = Addr;
+ /// getOrEmitGlobalVariable - Return the address of the specified global
+ /// variable, possibly emitting it to memory if needed. This is used by the
+ /// Emitter.
+ virtual void *getOrEmitGlobalVariable(const GlobalVariable *GV) {
+ return getPointerToGlobal((GlobalValue*)GV);
}
- // getPointerToGlobalIfAvailable - This returns the address of the specified
- // global value if it is available, otherwise it returns null.
- //
- void *getPointerToGlobalIfAvailable(const GlobalValue *GV) {
- std::map<const GlobalValue*, void*>::iterator I = GlobalAddress.find(GV);
- return I != GlobalAddress.end() ? I->second : 0;
+ /// Registers a listener to be called back on various events within
+ /// the JIT. See JITEventListener.h for more details. Does not
+ /// take ownership of the argument. The argument may be NULL, in
+ /// which case these functions do nothing.
+ virtual void RegisterJITEventListener(JITEventListener *) {}
+ virtual void UnregisterJITEventListener(JITEventListener *) {}
+
+ /// DisableLazyCompilation - When lazy compilation is off (the default), the
+ /// JIT will eagerly compile every function reachable from the argument to
+ /// getPointerToFunction. If lazy compilation is turned on, the JIT will only
+ /// compile the one function and emit stubs to compile the rest when they're
+ /// first called. If lazy compilation is turned off again while some lazy
+ /// stubs are still around, and one of those stubs is called, the program will
+ /// abort.
+ ///
+ /// In order to safely compile lazily in a threaded program, the user must
+ /// ensure that 1) only one thread at a time can call any particular lazy
+ /// stub, and 2) any thread modifying LLVM IR must hold the JIT's lock
+ /// (ExecutionEngine::lock) or otherwise ensure that no other thread calls a
+ /// lazy stub. See http://llvm.org/PR5184 for details.
+ void DisableLazyCompilation(bool Disabled = true) {
+ CompilingLazily = !Disabled;
+ }
+ bool isCompilingLazily() const {
+ return CompilingLazily;
+ }
+ // Deprecated in favor of isCompilingLazily (to reduce double-negatives).
+ // Remove this in LLVM 2.8.
+ bool isLazyCompilationDisabled() const {
+ return !CompilingLazily;
}
- // getPointerToGlobal - This returns the address of the specified global
- // value. This may involve code generation if it's a function.
- //
- void *getPointerToGlobal(const GlobalValue *GV);
+ /// DisableGVCompilation - If called, the JIT will abort if it's asked to
+ /// allocate space and populate a GlobalVariable that is not internal to
+ /// the module.
+ void DisableGVCompilation(bool Disabled = true) {
+ GVCompilationDisabled = Disabled;
+ }
+ bool isGVCompilationDisabled() const {
+ return GVCompilationDisabled;
+ }
- // getPointerToFunction - The different EE's represent function bodies in
- // different ways. They should each implement this to say what a function
- // pointer should look like.
- //
- virtual void *getPointerToFunction(Function *F) = 0;
+ /// DisableSymbolSearching - If called, the JIT will not try to lookup unknown
+ /// symbols with dlsym. A client can still use InstallLazyFunctionCreator to
+ /// resolve symbols in a custom way.
+ void DisableSymbolSearching(bool Disabled = true) {
+ SymbolSearchingDisabled = Disabled;
+ }
+ bool isSymbolSearchingDisabled() const {
+ return SymbolSearchingDisabled;
+ }
+
+ /// InstallLazyFunctionCreator - If an unknown function is needed, the
+ /// specified function pointer is invoked to create it. If it returns null,
+ /// the JIT will abort.
+ void InstallLazyFunctionCreator(void* (*P)(const std::string &)) {
+ LazyFunctionCreator = P;
+ }
+
+ /// InstallExceptionTableRegister - The JIT will use the given function
+ /// to register the exception tables it generates.
+ void InstallExceptionTableRegister(EERegisterFn F) {
+ ExceptionTableRegister = F;
+ }
+ void InstallExceptionTableDeregister(EERegisterFn F) {
+ ExceptionTableDeregister = F;
+ }
+
+ /// RegisterTable - Registers the given pointer as an exception table. It uses
+ /// the ExceptionTableRegister function.
+ void RegisterTable(void* res) {
+ if (ExceptionTableRegister) {
+ ExceptionTableRegister(res);
+ AllExceptionTables.push_back(res);
+ }
+ }
+
+ /// DeregisterAllTables - Deregisters all previously registered pointers to an
+ /// exception tables. It uses the ExceptionTableoDeregister function.
+ void DeregisterAllTables();
protected:
+ explicit ExecutionEngine(Module *M);
+
void emitGlobals();
-public: // FIXME: protected: // API shared among subclasses
+ // EmitGlobalVariable - This method emits the specified global variable to the
+ // address specified in GlobalAddresses, or allocates new memory if it's not
+ // already in the map.
+ void EmitGlobalVariable(const GlobalVariable *GV);
+
GenericValue getConstantValue(const Constant *C);
- void StoreValueToMemory(GenericValue Val, GenericValue *Ptr, const Type *Ty);
- GenericValue LoadValueFromMemory(GenericValue *Ptr, const Type *Ty);
- void *CreateArgv(const std::vector<std::string> &InputArgv);
- void InitializeMemory(const Constant *Init, void *Addr);
+ void LoadValueFromMemory(GenericValue &Result, GenericValue *Ptr,
+ const Type *Ty);
};
+namespace EngineKind {
+ // These are actually bitmasks that get or-ed together.
+ enum Kind {
+ JIT = 0x1,
+ Interpreter = 0x2
+ };
+ const static Kind Either = (Kind)(JIT | Interpreter);
+}
+
+/// EngineBuilder - Builder class for ExecutionEngines. Use this by
+/// stack-allocating a builder, chaining the various set* methods, and
+/// terminating it with a .create() call.
+class EngineBuilder {
+
+ private:
+ Module *M;
+ EngineKind::Kind WhichEngine;
+ std::string *ErrorStr;
+ CodeGenOpt::Level OptLevel;
+ JITMemoryManager *JMM;
+ bool AllocateGVsWithCode;
+ CodeModel::Model CMModel;
+ std::string MArch;
+ std::string MCPU;
+ SmallVector<std::string, 4> MAttrs;
+
+ /// InitEngine - Does the common initialization of default options.
+ ///
+ void InitEngine() {
+ WhichEngine = EngineKind::Either;
+ ErrorStr = NULL;
+ OptLevel = CodeGenOpt::Default;
+ JMM = NULL;
+ AllocateGVsWithCode = false;
+ CMModel = CodeModel::Default;
+ }
+
+ public:
+ /// EngineBuilder - Constructor for EngineBuilder. If create() is called and
+ /// is successful, the created engine takes ownership of the module.
+ EngineBuilder(Module *m) : M(m) {
+ InitEngine();
+ }
+
+ /// setEngineKind - Controls whether the user wants the interpreter, the JIT,
+ /// or whichever engine works. This option defaults to EngineKind::Either.
+ EngineBuilder &setEngineKind(EngineKind::Kind w) {
+ WhichEngine = w;
+ return *this;
+ }
+
+ /// setJITMemoryManager - Sets the memory manager to use. This allows
+ /// clients to customize their memory allocation policies. If create() is
+ /// called and is successful, the created engine takes ownership of the
+ /// memory manager. This option defaults to NULL.
+ EngineBuilder &setJITMemoryManager(JITMemoryManager *jmm) {
+ JMM = jmm;
+ return *this;
+ }
+
+ /// setErrorStr - Set the error string to write to on error. This option
+ /// defaults to NULL.
+ EngineBuilder &setErrorStr(std::string *e) {
+ ErrorStr = e;
+ return *this;
+ }
+
+ /// setOptLevel - Set the optimization level for the JIT. This option
+ /// defaults to CodeGenOpt::Default.
+ EngineBuilder &setOptLevel(CodeGenOpt::Level l) {
+ OptLevel = l;
+ return *this;
+ }
+
+ /// setCodeModel - Set the CodeModel that the ExecutionEngine target
+ /// data is using. Defaults to target specific default "CodeModel::Default".
+ EngineBuilder &setCodeModel(CodeModel::Model M) {
+ CMModel = M;
+ return *this;
+ }
+
+ /// setAllocateGVsWithCode - Sets whether global values should be allocated
+ /// into the same buffer as code. For most applications this should be set
+ /// to false. Allocating globals with code breaks freeMachineCodeForFunction
+ /// and is probably unsafe and bad for performance. However, we have clients
+ /// who depend on this behavior, so we must support it. This option defaults
+ /// to false so that users of the new API can safely use the new memory
+ /// manager and free machine code.
+ EngineBuilder &setAllocateGVsWithCode(bool a) {
+ AllocateGVsWithCode = a;
+ return *this;
+ }
+
+ /// setMArch - Override the architecture set by the Module's triple.
+ EngineBuilder &setMArch(StringRef march) {
+ MArch.assign(march.begin(), march.end());
+ return *this;
+ }
+
+ /// setMCPU - Target a specific cpu type.
+ EngineBuilder &setMCPU(StringRef mcpu) {
+ MCPU.assign(mcpu.begin(), mcpu.end());
+ return *this;
+ }
+
+ /// setMAttrs - Set cpu-specific attributes.
+ template<typename StringSequence>
+ EngineBuilder &setMAttrs(const StringSequence &mattrs) {
+ MAttrs.clear();
+ MAttrs.append(mattrs.begin(), mattrs.end());
+ return *this;
+ }
+
+ ExecutionEngine *create();
+};
+
+} // End llvm namespace
+
#endif