llvm-6502/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldCOFF.cpp
Lang Hames da62155c11 [MCJIT][Orc] Refactor RTDyldMemoryManager, weave RuntimeDyld::SymbolInfo through
MCJIT.

This patch decouples the two responsibilities of the RTDyldMemoryManager class,
memory management and symbol resolution, into two new classes:
RuntimeDyld::MemoryManager and RuntimeDyld::SymbolResolver.

The symbol resolution interface is modified slightly, from:

  uint64_t getSymbolAddress(const std::string &Name);

to:

  RuntimeDyld::SymbolInfo findSymbol(const std::string &Name);

The latter passes symbol flags along with symbol addresses, allowing RuntimeDyld
and others to reason about non-strong/non-exported symbols.


The memory management interface removes the following method:

  void notifyObjectLoaded(ExecutionEngine *EE,
                          const object::ObjectFile &) {}

as it is not related to memory management. (Note: Backwards compatibility *is*
maintained for this method in MCJIT and OrcMCJITReplacement, see below).


The RTDyldMemoryManager class remains in-tree for backwards compatibility.
It inherits directly from RuntimeDyld::SymbolResolver, and indirectly from
RuntimeDyld::MemoryManager via the new MCJITMemoryManager class, which
just subclasses RuntimeDyld::MemoryManager and reintroduces the
notifyObjectLoaded method for backwards compatibility).

The EngineBuilder class retains the existing method:

  EngineBuilder&
  setMCJITMemoryManager(std::unique_ptr<RTDyldMemoryManager> mcjmm);

and includes two new methods:

  EngineBuilder&
  setMemoryManager(std::unique_ptr<MCJITMemoryManager> MM);

  EngineBuilder&
  setSymbolResolver(std::unique_ptr<RuntimeDyld::SymbolResolver> SR);

Clients should use EITHER:

A single call to setMCJITMemoryManager with an RTDyldMemoryManager.

OR (exclusive)

One call each to each of setMemoryManager and setSymbolResolver.

This patch should be fully compatible with existing uses of RTDyldMemoryManager.
If it is not it should be considered a bug, and the patch either fixed or
reverted.

If clients find the new API to be an improvement the goal will be to deprecate
and eventually remove the RTDyldMemoryManager class in favor of the new classes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233509 91177308-0d34-0410-b5e6-96231b3b80d8
2015-03-30 03:37:06 +00:00

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2.5 KiB
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//===-- RuntimeDyldCOFF.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 COFF support for the MC-JIT runtime dynamic linker.
//
//===----------------------------------------------------------------------===//
#include "RuntimeDyldCOFF.h"
#include "Targets/RuntimeDyldCOFFX86_64.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/Object/ObjectFile.h"
using namespace llvm;
using namespace llvm::object;
#define DEBUG_TYPE "dyld"
namespace {
class LoadedCOFFObjectInfo : public RuntimeDyld::LoadedObjectInfo {
public:
LoadedCOFFObjectInfo(RuntimeDyldImpl &RTDyld, unsigned BeginIdx,
unsigned EndIdx)
: RuntimeDyld::LoadedObjectInfo(RTDyld, BeginIdx, EndIdx) {}
OwningBinary<ObjectFile>
getObjectForDebug(const ObjectFile &Obj) const override {
return OwningBinary<ObjectFile>();
}
};
}
namespace llvm {
std::unique_ptr<RuntimeDyldCOFF>
llvm::RuntimeDyldCOFF::create(Triple::ArchType Arch,
RuntimeDyld::MemoryManager &MemMgr,
RuntimeDyld::SymbolResolver &Resolver) {
switch (Arch) {
default:
llvm_unreachable("Unsupported target for RuntimeDyldCOFF.");
break;
case Triple::x86_64:
return make_unique<RuntimeDyldCOFFX86_64>(MemMgr, Resolver);
}
}
std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
RuntimeDyldCOFF::loadObject(const object::ObjectFile &O) {
unsigned SectionStartIdx, SectionEndIdx;
std::tie(SectionStartIdx, SectionEndIdx) = loadObjectImpl(O);
return llvm::make_unique<LoadedCOFFObjectInfo>(*this, SectionStartIdx,
SectionEndIdx);
}
uint64_t RuntimeDyldCOFF::getSymbolOffset(const SymbolRef &Sym) {
uint64_t Address;
if (Sym.getAddress(Address))
return UnknownAddressOrSize;
if (Address == UnknownAddressOrSize)
return UnknownAddressOrSize;
const ObjectFile *Obj = Sym.getObject();
section_iterator SecI(Obj->section_end());
if (Sym.getSection(SecI))
return UnknownAddressOrSize;
if (SecI == Obj->section_end())
return UnknownAddressOrSize;
uint64_t SectionAddress = SecI->getAddress();
return Address - SectionAddress;
}
bool RuntimeDyldCOFF::isCompatibleFile(const object::ObjectFile &Obj) const {
return Obj.isCOFF();
}
} // namespace llvm