llvm-6502/include/llvm/ExecutionEngine/ExecutionEngine.h
Owen Anderson 8e1fc56b24 Make it feasible for clients using EngineBuilder to capture the TargetMachine that is created as part of selecting the appropriate target.
This is necessary if the client wants to be able to mutate TargetOptions (for example, fast FP math mode) after the initial creation of the ExecutionEngine.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153342 91177308-0d34-0410-b5e6-96231b3b80d8
2012-03-23 17:40:56 +00:00

624 lines
24 KiB
C++

//===- 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 LLVM_EXECUTION_ENGINE_H
#define LLVM_EXECUTION_ENGINE_H
#include "llvm/MC/MCCodeGenInfo.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/ValueMap.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ValueHandle.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include <vector>
#include <map>
#include <string>
namespace llvm {
struct GenericValue;
class Constant;
class ExecutionEngine;
class Function;
class GlobalVariable;
class GlobalValue;
class JITEventListener;
class JITMemoryManager;
class MachineCodeInfo;
class Module;
class MutexGuard;
class TargetData;
class Triple;
class Type;
/// \brief Helper class for helping synchronize access to the global address map
/// table.
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;
}
/// \brief Erase an entry from the mapping table.
///
/// \returns The address that \arg ToUnmap was happed to.
void *RemoveMapping(const MutexGuard &, const GlobalValue *ToUnmap);
};
/// \brief Abstract interface for implementation execution of LLVM modules,
/// designed to support both interpreter and just-in-time (JIT) compiler
/// implementations.
class ExecutionEngine {
/// The state object holding the global address mapping, which must be
/// accessed synchronously.
//
// FIXME: There is no particular need the entire map needs to be
// synchronized. Wouldn't a reader-writer design be better here?
ExecutionEngineState EEState;
/// The target data for the platform for which execution is being performed.
const TargetData *TD;
/// Whether lazy JIT compilation is enabled.
bool CompilingLazily;
/// Whether JIT compilation of external global variables is allowed.
bool GVCompilationDisabled;
/// Whether the JIT should perform lookups of external symbols (e.g.,
/// using dlsym).
bool SymbolSearchingDisabled;
friend class EngineBuilder; // To allow access to JITCtor and InterpCtor.
protected:
/// The 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 execution engine implementations set these functions to ctor
// pointers at startup time if they are linked in.
static ExecutionEngine *(*JITCtor)(
Module *M,
std::string *ErrorStr,
JITMemoryManager *JMM,
bool GVsWithCode,
TargetMachine *TM);
static ExecutionEngine *(*MCJITCtor)(
Module *M,
std::string *ErrorStr,
JITMemoryManager *JMM,
bool GVsWithCode,
TargetMachine *TM);
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;
/// This maps functions to their exception tables frames.
DenseMap<const Function*, void*> AllExceptionTables;
public:
/// lock - This lock 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;
//===--------------------------------------------------------------------===//
// 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.
///
/// \param GVsWithCode - 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 compatibility,
/// this flag should be flipped to false, so that by default
/// freeMachineCodeForFunction works.
static ExecutionEngine *create(Module *M,
bool ForceInterpreter = false,
std::string *ErrorStr = 0,
CodeGenOpt::Level OptLevel =
CodeGenOpt::Default,
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,
Reloc::Model RM = Reloc::Default,
CodeModel::Model CMM =
CodeModel::JITDefault);
/// 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;
/// getPointerToNamedFunction - This method returns the address of the
/// specified function by using the dlsym function call. As such it is only
/// useful for resolving library symbols, not code generated symbols.
///
/// If AbortOnFailure is false and no function with the given name is
/// found, this function silently returns a null pointer. Otherwise,
/// it prints a message to stderr and aborts.
///
virtual void *getPointerToNamedFunction(const std::string &Name,
bool AbortOnFailure = true) = 0;
/// mapSectionAddress - map a section to its target address space value.
/// Map the address of a JIT section as returned from the memory manager
/// to the address in the target process as the running code will see it.
/// This is the address which will be used for relocation resolution.
virtual void mapSectionAddress(void *LocalAddress, uint64_t TargetAddress) {
llvm_unreachable("Re-mapping of section addresses not supported with this "
"EE!");
}
/// runStaticConstructorsDestructors - This method is used to execute all of
/// the static constructors or destructors for a program.
///
/// \param isDtors - Run the destructors instead of constructors.
void runStaticConstructorsDestructors(bool isDtors);
/// runStaticConstructorsDestructors - This method is used to execute all of
/// the static constructors or destructors for a particular module.
///
/// \param isDtors - Run the destructors instead of constructors.
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,
/// for use in dynamic compilation scenarios 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;
/// 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);
}
// 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.
///
const GlobalValue *getGlobalValueAtAddress(void *Addr);
/// StoreValueToMemory - Stores the data in Val of type Ty at address Ptr.
/// Ptr is the address of the memory at which to store Val, cast to
/// GenericValue *. It is not a pointer to a GenericValue containing the
/// address at which to store Val.
void StoreValueToMemory(const GenericValue &Val, GenericValue *Ptr,
Type *Ty);
void InitializeMemory(const Constant *Init, void *Addr);
/// 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().
virtual void *recompileAndRelinkFunction(Function *F) = 0;
/// freeMachineCodeForFunction - Release memory in the ExecutionEngine
/// corresponding to the machine code emitted to execute this function, useful
/// for garbage-collecting generated code.
virtual void freeMachineCodeForFunction(Function *F) = 0;
/// 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);
}
/// 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;
}
/// 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;
}
/// 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(const Function *fn, void* res) {
if (ExceptionTableRegister) {
ExceptionTableRegister(res);
AllExceptionTables[fn] = res;
}
}
/// DeregisterTable - Deregisters the exception frame previously registered
/// for the given function.
void DeregisterTable(const Function *Fn) {
if (ExceptionTableDeregister) {
DenseMap<const Function*, void*>::iterator frame =
AllExceptionTables.find(Fn);
if(frame != AllExceptionTables.end()) {
ExceptionTableDeregister(frame->second);
AllExceptionTables.erase(frame);
}
}
}
/// DeregisterAllTables - Deregisters all previously registered pointers to an
/// exception tables. It uses the ExceptionTableoDeregister function.
void DeregisterAllTables();
protected:
explicit ExecutionEngine(Module *M);
void emitGlobals();
void EmitGlobalVariable(const GlobalVariable *GV);
GenericValue getConstantValue(const Constant *C);
void LoadValueFromMemory(GenericValue &Result, GenericValue *Ptr,
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;
TargetOptions Options;
Reloc::Model RelocModel;
CodeModel::Model CMModel;
std::string MArch;
std::string MCPU;
SmallVector<std::string, 4> MAttrs;
bool UseMCJIT;
/// InitEngine - Does the common initialization of default options.
void InitEngine() {
WhichEngine = EngineKind::Either;
ErrorStr = NULL;
OptLevel = CodeGenOpt::Default;
JMM = NULL;
Options = TargetOptions();
AllocateGVsWithCode = false;
RelocModel = Reloc::Default;
CMModel = CodeModel::JITDefault;
UseMCJIT = false;
}
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;
}
/// setTargetOptions - Set the target options that the ExecutionEngine
/// target is using. Defaults to TargetOptions().
EngineBuilder &setTargetOptions(const TargetOptions &Opts) {
Options = Opts;
return *this;
}
/// setRelocationModel - Set the relocation model that the ExecutionEngine
/// target is using. Defaults to target specific default "Reloc::Default".
EngineBuilder &setRelocationModel(Reloc::Model RM) {
RelocModel = RM;
return *this;
}
/// setCodeModel - Set the CodeModel that the ExecutionEngine target
/// data is using. Defaults to target specific default
/// "CodeModel::JITDefault".
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;
}
/// setUseMCJIT - Set whether the MC-JIT implementation should be used
/// (experimental).
EngineBuilder &setUseMCJIT(bool Value) {
UseMCJIT = Value;
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;
}
TargetMachine *selectTarget();
/// selectTarget - Pick a target either via -march or by guessing the native
/// arch. Add any CPU features specified via -mcpu or -mattr.
TargetMachine *selectTarget(const Triple &TargetTriple,
StringRef MArch,
StringRef MCPU,
const SmallVectorImpl<std::string>& MAttrs);
ExecutionEngine *create() {
return create(selectTarget());
}
ExecutionEngine *create(TargetMachine *TM);
};
} // End llvm namespace
#endif