llvm-6502/include/llvm/ExecutionEngine/RuntimeDyld.h
2013-01-10 00:45:19 +00:00

117 lines
4.8 KiB
C++

//===-- RuntimeDyld.h - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Interface for the runtime dynamic linker facilities of the MC-JIT.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_EXECUTIONENGINE_RUNTIMEDYLD_H
#define LLVM_EXECUTIONENGINE_RUNTIMEDYLD_H
#include "llvm/ADT/StringRef.h"
#include "llvm/ExecutionEngine/ObjectBuffer.h"
#include "llvm/Support/Memory.h"
namespace llvm {
class RuntimeDyldImpl;
class ObjectImage;
// RuntimeDyld clients often want to handle the memory management of
// what gets placed where. For JIT clients, this is the subset of
// JITMemoryManager required for dynamic loading of binaries.
//
// FIXME: As the RuntimeDyld fills out, additional routines will be needed
// for the varying types of objects to be allocated.
class RTDyldMemoryManager {
RTDyldMemoryManager(const RTDyldMemoryManager&) LLVM_DELETED_FUNCTION;
void operator=(const RTDyldMemoryManager&) LLVM_DELETED_FUNCTION;
public:
RTDyldMemoryManager() {}
virtual ~RTDyldMemoryManager();
/// Allocate a memory block of (at least) the given size suitable for
/// executable code. The SectionID is a unique identifier assigned by the JIT
/// engine, and optionally recorded by the memory manager to access a loaded
/// section.
virtual uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
unsigned SectionID) = 0;
/// Allocate a memory block of (at least) the given size suitable for data.
/// The SectionID is a unique identifier assigned by the JIT engine, and
/// optionally recorded by the memory manager to access a loaded section.
virtual uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
unsigned SectionID, bool IsReadOnly) = 0;
/// This method returns the address of the specified function. 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 returns a null pointer. Otherwise, it prints a
/// message to stderr and aborts.
virtual void *getPointerToNamedFunction(const std::string &Name,
bool AbortOnFailure = true) = 0;
/// This method is called when object loading is complete and section page
/// permissions can be applied. It is up to the memory manager implementation
/// to decide whether or not to act on this method. The memory manager will
/// typically allocate all sections as read-write and then apply specific
/// permissions when this method is called.
///
/// Returns true if an error occurred, false otherwise.
virtual bool applyPermissions(std::string *ErrMsg = 0) = 0;
};
class RuntimeDyld {
RuntimeDyld(const RuntimeDyld &) LLVM_DELETED_FUNCTION;
void operator=(const RuntimeDyld &) LLVM_DELETED_FUNCTION;
// RuntimeDyldImpl is the actual class. RuntimeDyld is just the public
// interface.
RuntimeDyldImpl *Dyld;
RTDyldMemoryManager *MM;
protected:
// Change the address associated with a section when resolving relocations.
// Any relocations already associated with the symbol will be re-resolved.
void reassignSectionAddress(unsigned SectionID, uint64_t Addr);
public:
RuntimeDyld(RTDyldMemoryManager *);
~RuntimeDyld();
/// Prepare the object contained in the input buffer for execution.
/// Ownership of the input buffer is transferred to the ObjectImage
/// instance returned from this function if successful. In the case of load
/// failure, the input buffer will be deleted.
ObjectImage *loadObject(ObjectBuffer *InputBuffer);
/// Get the address of our local copy of the symbol. This may or may not
/// be the address used for relocation (clients can copy the data around
/// and resolve relocatons based on where they put it).
void *getSymbolAddress(StringRef Name);
/// Get the address of the target copy of the symbol. This is the address
/// used for relocation.
uint64_t getSymbolLoadAddress(StringRef Name);
/// Resolve the relocations for all symbols we currently know about.
void resolveRelocations();
/// 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.
void mapSectionAddress(const void *LocalAddress, uint64_t TargetAddress);
StringRef getErrorString();
};
} // end namespace llvm
#endif