#ifndef LLVM_RUNTIME_DYLD_MACHO_H
#define LLVM_RUNTIME_DYLD_MACHO_H
-#include "llvm/ADT/IndexedMap.h"
-#include "llvm/Object/MachOObject.h"
-#include "llvm/Support/Format.h"
+#include "ObjectImageCommon.h"
#include "RuntimeDyldImpl.h"
+#include "llvm/Object/MachO.h"
+#include "llvm/Support/Format.h"
+
+#define DEBUG_TYPE "dyld"
using namespace llvm;
using namespace llvm::object;
-
namespace llvm {
class RuntimeDyldMachO : public RuntimeDyldImpl {
-
- // For each symbol, keep a list of relocations based on it. Anytime
- // its address is reassigned (the JIT re-compiled the function, e.g.),
- // the relocations get re-resolved.
- // The symbol (or section) the relocation is sourced from is the Key
- // in the relocation list where it's stored.
- struct RelocationEntry {
- unsigned SectionID; // Section the relocation is contained in.
- uint64_t Offset; // Offset into the section for the relocation.
- uint32_t Data; // Second word of the raw macho relocation entry.
- int64_t Addend; // Addend encoded in the instruction itself, if any,
- // plus the offset into the source section for
- // the symbol once the relocation is resolvable.
-
- RelocationEntry(unsigned id, uint64_t offset, uint32_t data, int64_t addend)
- : SectionID(id), Offset(offset), Data(data), Addend(addend) {}
+protected:
+ struct SectionOffsetPair {
+ unsigned SectionID;
+ uint64_t Offset;
};
- typedef SmallVector<RelocationEntry, 4> RelocationList;
-
- // For each section, keep a list of referrers in that section that are clients
- // of relocations in other sections. Whenever a relocation gets created,
- // create a corresponding referrer. Whenever relocations are re-resolved,
- // re-resolve the referrers' relocations as well.
- struct Referrer {
- unsigned SectionID; // Section whose RelocationList contains the relocation.
- uint32_t Index; // Index of the RelocatonEntry in that RelocationList.
-
- Referrer(unsigned id, uint32_t index)
- : SectionID(id), Index(index) {}
+
+ struct EHFrameRelatedSections {
+ EHFrameRelatedSections()
+ : EHFrameSID(RTDYLD_INVALID_SECTION_ID),
+ TextSID(RTDYLD_INVALID_SECTION_ID),
+ ExceptTabSID(RTDYLD_INVALID_SECTION_ID) {}
+ EHFrameRelatedSections(SID EH, SID T, SID Ex)
+ : EHFrameSID(EH), TextSID(T), ExceptTabSID(Ex) {}
+ SID EHFrameSID;
+ SID TextSID;
+ SID ExceptTabSID;
};
- typedef SmallVector<Referrer, 4> ReferrerList;
-
- // Relocations to sections already loaded. Indexed by SectionID which is the
- // source of the address. The target where the address will be writen is
- // SectionID/Offset in the relocation itself.
- IndexedMap<RelocationList> Relocations;
- // Referrers corresponding to Relocations.
- IndexedMap<ReferrerList> Referrers;
- // Relocations to symbols that are not yet resolved. Must be external
- // relocations by definition. Indexed by symbol name.
- StringMap<RelocationList> UnresolvedRelocations;
-
- bool resolveRelocation(uint8_t *LocalAddress,
- uint64_t FinalAddress,
- uint64_t Value,
- bool isPCRel,
- unsigned Type,
- unsigned Size,
- int64_t Addend);
- bool resolveX86_64Relocation(uint8_t *LocalAddress,
- uint64_t FinalAddress,
- uint64_t Value,
- bool isPCRel,
- unsigned Type,
- unsigned Size,
- int64_t Addend);
- bool resolveARMRelocation(uint8_t *LocalAddress,
- uint64_t FinalAddress,
- uint64_t Value,
- bool isPCRel,
- unsigned Type,
- unsigned Size,
- int64_t Addend);
-
- bool loadSegment32(const MachOObject *Obj,
- const MachOObject::LoadCommandInfo *SegmentLCI,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
- bool loadSegment64(const MachOObject *Obj,
- const MachOObject::LoadCommandInfo *SegmentLCI,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
- bool processSymbols32(const MachOObject *Obj,
- SmallVectorImpl<unsigned> &SectionMap,
- SmallVectorImpl<StringRef> &SymbolNames,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
- bool processSymbols64(const MachOObject *Obj,
- SmallVectorImpl<unsigned> &SectionMap,
- SmallVectorImpl<StringRef> &SymbolNames,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
-
- void resolveSymbol(StringRef Name);
-public:
+ // When a module is loaded we save the SectionID of the EH frame section
+ // in a table until we receive a request to register all unregistered
+ // EH frame sections with the memory manager.
+ SmallVector<EHFrameRelatedSections, 2> UnregisteredEHFrameSections;
+
RuntimeDyldMachO(RTDyldMemoryManager *mm) : RuntimeDyldImpl(mm) {}
- bool loadObject(MemoryBuffer *InputBuffer);
+ /// Extract the addend encoded in the instruction.
+ uint64_t decodeAddend(uint8_t *LocalAddress, unsigned NumBytes,
+ uint32_t RelType) const;
+
+ /// Construct a RelocationValueRef representing the relocation target.
+ /// For Symbols in known sections, this will return a RelocationValueRef
+ /// representing a (SectionID, Offset) pair.
+ /// For Symbols whose section is not known, this will return a
+ /// (SymbolName, Offset) pair, where the Offset is taken from the instruction
+ /// immediate (held in RE.Addend).
+ /// In both cases the Addend field is *NOT* fixed up to be PC-relative. That
+ /// should be done by the caller where appropriate by calling makePCRel on
+ /// the RelocationValueRef.
+ RelocationValueRef getRelocationValueRef(ObjectImage &ObjImg,
+ const relocation_iterator &RI,
+ const RelocationEntry &RE,
+ ObjSectionToIDMap &ObjSectionToID,
+ const SymbolTableMap &Symbols);
+
+ /// Make the RelocationValueRef addend PC-relative.
+ void makeValueAddendPCRel(RelocationValueRef &Value, ObjectImage &ObjImg,
+ const relocation_iterator &RI);
+
+ /// Dump information about the relocation entry (RE) and resolved value.
+ void dumpRelocationToResolve(const RelocationEntry &RE, uint64_t Value) const;
+
+public:
+ /// Create an ObjectImage from the given ObjectBuffer.
+ static ObjectImage *createObjectImage(ObjectBuffer *InputBuffer) {
+ return new ObjectImageCommon(InputBuffer);
+ }
+
+ /// Create an ObjectImage from the given ObjectFile.
+ static ObjectImage *
+ createObjectImageFromFile(std::unique_ptr<object::ObjectFile> InputObject) {
+ return new ObjectImageCommon(std::move(InputObject));
+ }
+
+ /// Create a RuntimeDyldMachO instance for the given target architecture.
+ static std::unique_ptr<RuntimeDyldMachO> create(Triple::ArchType Arch,
+ RTDyldMemoryManager *mm);
+
+ /// Write the least significant 'Size' bytes in 'Value' out at the address
+ /// pointed to by Addr. Check for overflow.
+ bool writeBytesUnaligned(uint8_t *Addr, uint64_t Value, unsigned Size);
- void reassignSectionAddress(unsigned SectionID, uint64_t Addr);
+ SectionEntry &getSection(unsigned SectionID) { return Sections[SectionID]; }
- static bool isKnownFormat(const MemoryBuffer *InputBuffer);
+ bool isCompatibleFormat(const ObjectBuffer *Buffer) const override;
+ bool isCompatibleFile(const object::ObjectFile *Obj) const override;
+ void registerEHFrames() override;
+};
- bool isCompatibleFormat(const MemoryBuffer *InputBuffer) const {
- return isKnownFormat(InputBuffer);
+/// RuntimeDyldMachOTarget - Templated base class for generic MachO linker
+/// algorithms and data structures.
+///
+/// Concrete, target specific sub-classes can be accessed via the impl()
+/// methods. (i.e. the RuntimeDyldMachO hierarchy uses the Curiously
+/// Recurring Template Idiom). Concrete subclasses for each target
+/// can be found in ./Targets.
+template <typename Impl>
+class RuntimeDyldMachOCRTPBase : public RuntimeDyldMachO {
+private:
+ Impl &impl() { return static_cast<Impl &>(*this); }
+ const Impl &impl() const { return static_cast<const Impl &>(*this); }
+
+protected:
+
+ /// Parse the given relocation, which must be a non-scattered, and
+ /// return a RelocationEntry representing the information. The 'Addend' field
+ /// will contain the unmodified instruction immediate.
+ RelocationEntry getBasicRelocationEntry(unsigned SectionID,
+ ObjectImage &ObjImg,
+ const relocation_iterator &RI) const {
+ const MachOObjectFile &Obj =
+ static_cast<const MachOObjectFile &>(*ObjImg.getObjectFile());
+ MachO::any_relocation_info RelInfo =
+ Obj.getRelocation(RI->getRawDataRefImpl());
+
+ const SectionEntry &Section = Sections[SectionID];
+ bool IsPCRel = Obj.getAnyRelocationPCRel(RelInfo);
+ unsigned Size = Obj.getAnyRelocationLength(RelInfo);
+ uint64_t Offset;
+ RI->getOffset(Offset);
+ uint8_t *LocalAddress = Section.Address + Offset;
+ unsigned NumBytes = 1 << Size;
+ uint32_t RelType = Obj.getAnyRelocationType(RelInfo);
+ uint64_t Addend = impl().decodeAddend(LocalAddress, NumBytes, RelType);
+
+ return RelocationEntry(SectionID, Offset, RelType, Addend, IsPCRel, Size);
+ }
+
+public:
+ RuntimeDyldMachOCRTPBase(RTDyldMemoryManager *mm) : RuntimeDyldMachO(mm) {}
+
+ void finalizeLoad(ObjectImage &ObjImg, ObjSectionToIDMap &SectionMap) {
+ unsigned EHFrameSID = RTDYLD_INVALID_SECTION_ID;
+ unsigned TextSID = RTDYLD_INVALID_SECTION_ID;
+ unsigned ExceptTabSID = RTDYLD_INVALID_SECTION_ID;
+ ObjSectionToIDMap::iterator i, e;
+
+ for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
+ const SectionRef &Section = i->first;
+ StringRef Name;
+ Section.getName(Name);
+ if (Name == "__eh_frame")
+ EHFrameSID = i->second;
+ else if (Name == "__text")
+ TextSID = i->second;
+ else if (Name == "__gcc_except_tab")
+ ExceptTabSID = i->second;
+ else
+ impl().finalizeSection(ObjImg, i->second, Section);
+ }
+ UnregisteredEHFrameSections.push_back(
+ EHFrameRelatedSections(EHFrameSID, TextSID, ExceptTabSID));
}
};
} // end namespace llvm
+#undef DEBUG_TYPE
+
#endif