llvm-6502/include/llvm/ExecutionEngine/ExecutionEngine.h
2006-11-09 19:30:47 +00:00

226 lines
8.2 KiB
C++

//===- ExecutionEngine.h - Abstract Execution Engine Interface --*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and 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
#include <vector>
#include <map>
#include <cassert>
#include <string>
#include "llvm/System/Mutex.h"
#include "llvm/ADT/SmallVector.h"
namespace llvm {
union GenericValue;
class Constant;
class Function;
class GlobalVariable;
class GlobalValue;
class Module;
class ModuleProvider;
class TargetData;
class Type;
class MutexGuard;
class ExecutionEngineState {
private:
/// GlobalAddressMap - A mapping between LLVM global values and their
/// actualized version...
std::map<const GlobalValue*, void *> 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 *, const GlobalValue*> GlobalAddressReverseMap;
public:
std::map<const GlobalValue*, void *> &
getGlobalAddressMap(const MutexGuard &locked) {
return GlobalAddressMap;
}
std::map<void*, const GlobalValue*> &
getGlobalAddressReverseMap(const MutexGuard& locked) {
return GlobalAddressReverseMap;
}
};
class ExecutionEngine {
const TargetData *TD;
ExecutionEngineState state;
bool LazyCompilationDisabled;
protected:
/// Modules - This is a list of ModuleProvider's that we are JIT'ing from. We
/// use a smallvector to optimize for the case where there is only one module.
SmallVector<ModuleProvider*, 1> Modules;
void setTargetData(const TargetData *td) {
TD = td;
}
// 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.
typedef ExecutionEngine *(*EECtorFn)(ModuleProvider*);
static EECtorFn JITCtor, InterpCtor;
public:
/// 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(ModuleProvider *P);
ExecutionEngine(Module *M);
virtual ~ExecutionEngine();
const TargetData *getTargetData() const { return TD; }
/// addModuleProvider - Add a ModuleProvider to the list of modules that we
/// can JIT from. Note that this takes ownership of the ModuleProvider: when
/// the ExecutionEngine is destroyed, it destroys the MP as well.
void addModuleProvider(ModuleProvider *P) {
Modules.push_back(P);
}
/// 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);
/// create - This is the factory method for creating an execution engine which
/// is appropriate for the current machine.
static ExecutionEngine *create(ModuleProvider *MP,
bool ForceInterpreter = false);
/// 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 module, depending on the
/// value of isDtors.
void runStaticConstructorsDestructors(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.
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();
/// 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.
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.
///
virtual void *getPointerToFunction(Function *F) = 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.
///
virtual void *getPointerToFunctionOrStub(Function *F) {
// Default implementation, just codegen the function.
return getPointerToFunction(F);
}
/// getGlobalValueAtAddress - Return the LLVM global value object that starts
/// at the specified address.
///
const GlobalValue *getGlobalValueAtAddress(void *Addr);
void StoreValueToMemory(GenericValue Val, GenericValue *Ptr, const 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);
}
/// DisableLazyCompilation - If called, the JIT will abort if lazy compilation
// is ever attempted.
void DisableLazyCompilation() {
LazyCompilationDisabled = true;
}
bool isLazyCompilationDisabled() const {
return LazyCompilationDisabled;
}
protected:
void emitGlobals();
// 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);
GenericValue LoadValueFromMemory(GenericValue *Ptr, const Type *Ty);
};
} // End llvm namespace
#endif