llvm-6502/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
Eli Bendersky a66a18505e Adding a basic ELF dynamic loader and MC-JIT for ELF. Functionality is currently basic and will be enhanced with future patches.
Patch developed by Andy Kaylor and Daniel Malea. Reviewed on llvm-commits.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148231 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-16 08:56:09 +00:00

121 lines
4.0 KiB
C++

//===-- RuntimeDyld.cpp - 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.
//
//===----------------------------------------------------------------------===//
//
// Implementation of the MC-JIT runtime dynamic linker.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "dyld"
#include "RuntimeDyldImpl.h"
#include "llvm/Support/Path.h"
using namespace llvm;
using namespace llvm::object;
// Empty out-of-line virtual destructor as the key function.
RTDyldMemoryManager::~RTDyldMemoryManager() {}
RuntimeDyldImpl::~RuntimeDyldImpl() {}
namespace llvm {
void RuntimeDyldImpl::extractFunction(StringRef Name, uint8_t *StartAddress,
uint8_t *EndAddress) {
// Allocate memory for the function via the memory manager.
uintptr_t Size = EndAddress - StartAddress + 1;
uintptr_t AllocSize = Size;
uint8_t *Mem = MemMgr->startFunctionBody(Name.data(), AllocSize);
assert(Size >= (uint64_t)(EndAddress - StartAddress + 1) &&
"Memory manager failed to allocate enough memory!");
// Copy the function payload into the memory block.
memcpy(Mem, StartAddress, Size);
MemMgr->endFunctionBody(Name.data(), Mem, Mem + Size);
// Remember where we put it.
Functions[Name] = sys::MemoryBlock(Mem, Size);
// Default the assigned address for this symbol to wherever this
// allocated it.
SymbolTable[Name] = Mem;
DEBUG(dbgs() << " allocated to [" << Mem << ", " << Mem + Size << "]\n");
}
// Resolve the relocations for all symbols we currently know about.
void RuntimeDyldImpl::resolveRelocations() {
// Just iterate over the symbols in our symbol table and assign their
// addresses.
StringMap<uint8_t*>::iterator i = SymbolTable.begin();
StringMap<uint8_t*>::iterator e = SymbolTable.end();
for (;i != e; ++i)
reassignSymbolAddress(i->getKey(), i->getValue());
}
//===----------------------------------------------------------------------===//
// RuntimeDyld class implementation
RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *mm) {
Dyld = 0;
MM = mm;
}
RuntimeDyld::~RuntimeDyld() {
delete Dyld;
}
bool RuntimeDyld::loadObject(MemoryBuffer *InputBuffer) {
if (!Dyld) {
sys::LLVMFileType type = sys::IdentifyFileType(
InputBuffer->getBufferStart(),
static_cast<unsigned>(InputBuffer->getBufferSize()));
switch (type) {
case sys::ELF_Relocatable_FileType:
case sys::ELF_Executable_FileType:
case sys::ELF_SharedObject_FileType:
case sys::ELF_Core_FileType:
Dyld = new RuntimeDyldELF(MM);
break;
case sys::Mach_O_Object_FileType:
case sys::Mach_O_Executable_FileType:
case sys::Mach_O_FixedVirtualMemorySharedLib_FileType:
case sys::Mach_O_Core_FileType:
case sys::Mach_O_PreloadExecutable_FileType:
case sys::Mach_O_DynamicallyLinkedSharedLib_FileType:
case sys::Mach_O_DynamicLinker_FileType:
case sys::Mach_O_Bundle_FileType:
case sys::Mach_O_DynamicallyLinkedSharedLibStub_FileType:
case sys::Mach_O_DSYMCompanion_FileType:
Dyld = new RuntimeDyldMachO(MM);
break;
case sys::Unknown_FileType:
case sys::Bitcode_FileType:
case sys::Archive_FileType:
case sys::COFF_FileType:
report_fatal_error("Incompatible object format!");
}
} else {
if (!Dyld->isCompatibleFormat(InputBuffer))
report_fatal_error("Incompatible object format!");
}
return Dyld->loadObject(InputBuffer);
}
void *RuntimeDyld::getSymbolAddress(StringRef Name) {
return Dyld->getSymbolAddress(Name);
}
void RuntimeDyld::resolveRelocations() {
Dyld->resolveRelocations();
}
void RuntimeDyld::reassignSymbolAddress(StringRef Name, uint8_t *Addr) {
Dyld->reassignSymbolAddress(Name, Addr);
}
StringRef RuntimeDyld::getErrorString() {
return Dyld->getErrorString();
}
} // end namespace llvm