X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FExecutionEngine%2FRuntimeDyld%2FRuntimeDyldMachO.cpp;h=d12e7e5e4dcf2f6845dad18d27d386064134f4af;hb=42fdb1f00ffc5d0a0326f11cadaeec1c26691688;hp=32cf2a8594772463c0ae0ab399b55acde0f5b705;hpb=e0934bee3a4f40731169bc42b15a39ce39978175;p=oota-llvm.git diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp index 32cf2a85947..d12e7e5e4dc 100644 --- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp @@ -12,76 +12,267 @@ //===----------------------------------------------------------------------===// #define DEBUG_TYPE "dyld" +#include "RuntimeDyldMachO.h" #include "llvm/ADT/OwningPtr.h" -#include "llvm/ADT/StringRef.h" #include "llvm/ADT/STLExtras.h" -#include "RuntimeDyldImpl.h" +#include "llvm/ADT/StringRef.h" using namespace llvm; using namespace llvm::object; namespace llvm { -bool RuntimeDyldMachO:: -resolveRelocation(uint8_t *Address, uint64_t Value, bool isPCRel, - unsigned Type, unsigned Size, int64_t Addend) { +static unsigned char *processFDE(unsigned char *P, intptr_t DeltaForText, intptr_t DeltaForEH) { + uint32_t Length = *((uint32_t*)P); + P += 4; + unsigned char *Ret = P + Length; + uint32_t Offset = *((uint32_t*)P); + if (Offset == 0) // is a CIE + return Ret; + + P += 4; + intptr_t FDELocation = *((intptr_t*)P); + intptr_t NewLocation = FDELocation - DeltaForText; + *((intptr_t*)P) = NewLocation; + P += sizeof(intptr_t); + + // Skip the FDE address range + P += sizeof(intptr_t); + + uint8_t Augmentationsize = *P; + P += 1; + if (Augmentationsize != 0) { + intptr_t LSDA = *((intptr_t*)P); + intptr_t NewLSDA = LSDA - DeltaForEH; + *((intptr_t*)P) = NewLSDA; + } + + return Ret; +} + +static intptr_t computeDelta(SectionEntry *A, SectionEntry *B) { + intptr_t ObjDistance = A->ObjAddress - B->ObjAddress; + intptr_t MemDistance = A->LoadAddress - B->LoadAddress; + return ObjDistance - MemDistance; +} + +void RuntimeDyldMachO::registerEHFrames() { + + if (!MemMgr) + return; + for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) { + EHFrameRelatedSections &SectionInfo = UnregisteredEHFrameSections[i]; + if (SectionInfo.EHFrameSID == RTDYLD_INVALID_SECTION_ID || + SectionInfo.TextSID == RTDYLD_INVALID_SECTION_ID) + continue; + SectionEntry *Text = &Sections[SectionInfo.TextSID]; + SectionEntry *EHFrame = &Sections[SectionInfo.EHFrameSID]; + SectionEntry *ExceptTab = NULL; + if (SectionInfo.ExceptTabSID != RTDYLD_INVALID_SECTION_ID) + ExceptTab = &Sections[SectionInfo.ExceptTabSID]; + + intptr_t DeltaForText = computeDelta(Text, EHFrame); + intptr_t DeltaForEH = 0; + if (ExceptTab) + DeltaForEH = computeDelta(ExceptTab, EHFrame); + + unsigned char *P = EHFrame->Address; + unsigned char *End = P + EHFrame->Size; + do { + P = processFDE(P, DeltaForText, DeltaForEH); + } while(P != End); + + MemMgr->registerEHFrames(EHFrame->Address, + EHFrame->LoadAddress, + EHFrame->Size); + } + UnregisteredEHFrameSections.clear(); +} + +void RuntimeDyldMachO::finalizeLoad(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; + } + UnregisteredEHFrameSections.push_back(EHFrameRelatedSections(EHFrameSID, + TextSID, + ExceptTabSID)); +} + +// The target location for the relocation is described by RE.SectionID and +// RE.Offset. RE.SectionID can be used to find the SectionEntry. Each +// SectionEntry has three members describing its location. +// SectionEntry::Address is the address at which the section has been loaded +// into memory in the current (host) process. SectionEntry::LoadAddress is the +// address that the section will have in the target process. +// SectionEntry::ObjAddress is the address of the bits for this section in the +// original emitted object image (also in the current address space). +// +// Relocations will be applied as if the section were loaded at +// SectionEntry::LoadAddress, but they will be applied at an address based +// on SectionEntry::Address. SectionEntry::ObjAddress will be used to refer to +// Target memory contents if they are required for value calculations. +// +// The Value parameter here is the load address of the symbol for the +// relocation to be applied. For relocations which refer to symbols in the +// current object Value will be the LoadAddress of the section in which +// the symbol resides (RE.Addend provides additional information about the +// symbol location). For external symbols, Value will be the address of the +// symbol in the target address space. +void RuntimeDyldMachO::resolveRelocation(const RelocationEntry &RE, + uint64_t Value) { + const SectionEntry &Section = Sections[RE.SectionID]; + return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend, + RE.IsPCRel, RE.Size); +} + +void RuntimeDyldMachO::resolveRelocation(const SectionEntry &Section, + uint64_t Offset, + uint64_t Value, + uint32_t Type, + int64_t Addend, + bool isPCRel, + unsigned LogSize) { + uint8_t *LocalAddress = Section.Address + Offset; + uint64_t FinalAddress = Section.LoadAddress + Offset; + unsigned MachoType = Type; + unsigned Size = 1 << LogSize; + + DEBUG(dbgs() << "resolveRelocation LocalAddress: " + << format("%p", LocalAddress) + << " FinalAddress: " << format("%p", FinalAddress) + << " Value: " << format("%p", Value) + << " Addend: " << Addend + << " isPCRel: " << isPCRel + << " MachoType: " << MachoType + << " Size: " << Size + << "\n"); + // This just dispatches to the proper target specific routine. - switch (CPUType) { - default: assert(0 && "Unsupported CPU type!"); - case mach::CTM_x86_64: - return resolveX86_64Relocation((uintptr_t)Address, (uintptr_t)Value, - isPCRel, Type, Size, Addend); - case mach::CTM_ARM: - return resolveARMRelocation((uintptr_t)Address, (uintptr_t)Value, - isPCRel, Type, Size, Addend); + switch (Arch) { + default: llvm_unreachable("Unsupported CPU type!"); + case Triple::x86_64: + resolveX86_64Relocation(LocalAddress, + FinalAddress, + (uintptr_t)Value, + isPCRel, + MachoType, + Size, + Addend); + break; + case Triple::x86: + resolveI386Relocation(LocalAddress, + FinalAddress, + (uintptr_t)Value, + isPCRel, + MachoType, + Size, + Addend); + break; + case Triple::arm: // Fall through. + case Triple::thumb: + resolveARMRelocation(LocalAddress, + FinalAddress, + (uintptr_t)Value, + isPCRel, + MachoType, + Size, + Addend); + break; } - llvm_unreachable(""); } -bool RuntimeDyldMachO:: -resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel, - unsigned Type, unsigned Size, int64_t Addend) { +bool RuntimeDyldMachO::resolveI386Relocation(uint8_t *LocalAddress, + uint64_t FinalAddress, + uint64_t Value, + bool isPCRel, + unsigned Type, + unsigned Size, + int64_t Addend) { + if (isPCRel) + Value -= FinalAddress + 4; // see resolveX86_64Relocation + + switch (Type) { + default: + llvm_unreachable("Invalid relocation type!"); + case MachO::GENERIC_RELOC_VANILLA: { + uint8_t *p = LocalAddress; + uint64_t ValueToWrite = Value + Addend; + for (unsigned i = 0; i < Size; ++i) { + *p++ = (uint8_t)(ValueToWrite & 0xff); + ValueToWrite >>= 8; + } + return false; + } + case MachO::GENERIC_RELOC_SECTDIFF: + case MachO::GENERIC_RELOC_LOCAL_SECTDIFF: + case MachO::GENERIC_RELOC_PB_LA_PTR: + return Error("Relocation type not implemented yet!"); + } +} + +bool RuntimeDyldMachO::resolveX86_64Relocation(uint8_t *LocalAddress, + uint64_t FinalAddress, + uint64_t Value, + bool isPCRel, + unsigned Type, + unsigned Size, + int64_t Addend) { // If the relocation is PC-relative, the value to be encoded is the // pointer difference. if (isPCRel) // FIXME: It seems this value needs to be adjusted by 4 for an effective PC // address. Is that expected? Only for branches, perhaps? - Value -= Address + 4; + Value -= FinalAddress + 4; switch(Type) { default: llvm_unreachable("Invalid relocation type!"); - case macho::RIT_X86_64_Signed1: - case macho::RIT_X86_64_Signed2: - case macho::RIT_X86_64_Signed4: - case macho::RIT_X86_64_Signed: - case macho::RIT_X86_64_Unsigned: - case macho::RIT_X86_64_Branch: { + case MachO::X86_64_RELOC_SIGNED_1: + case MachO::X86_64_RELOC_SIGNED_2: + case MachO::X86_64_RELOC_SIGNED_4: + case MachO::X86_64_RELOC_SIGNED: + case MachO::X86_64_RELOC_UNSIGNED: + case MachO::X86_64_RELOC_BRANCH: { Value += Addend; // Mask in the target value a byte at a time (we don't have an alignment // guarantee for the target address, so this is safest). - uint8_t *p = (uint8_t*)Address; + uint8_t *p = (uint8_t*)LocalAddress; for (unsigned i = 0; i < Size; ++i) { *p++ = (uint8_t)Value; Value >>= 8; } return false; } - case macho::RIT_X86_64_GOTLoad: - case macho::RIT_X86_64_GOT: - case macho::RIT_X86_64_Subtractor: - case macho::RIT_X86_64_TLV: + case MachO::X86_64_RELOC_GOT_LOAD: + case MachO::X86_64_RELOC_GOT: + case MachO::X86_64_RELOC_SUBTRACTOR: + case MachO::X86_64_RELOC_TLV: return Error("Relocation type not implemented yet!"); } - return false; } -bool RuntimeDyldMachO:: -resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel, - unsigned Type, unsigned Size, int64_t Addend) { +bool RuntimeDyldMachO::resolveARMRelocation(uint8_t *LocalAddress, + uint64_t FinalAddress, + uint64_t Value, + bool isPCRel, + unsigned Type, + unsigned Size, + int64_t Addend) { // If the relocation is PC-relative, the value to be encoded is the // pointer difference. if (isPCRel) { - Value -= Address; + Value -= FinalAddress; // ARM PCRel relocations have an effective-PC offset of two instructions // (four bytes in Thumb mode, 8 bytes in ARM mode). // FIXME: For now, assume ARM mode. @@ -91,21 +282,20 @@ resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel, switch(Type) { default: llvm_unreachable("Invalid relocation type!"); - case macho::RIT_Vanilla: { - llvm_unreachable("Invalid relocation type!"); + case MachO::ARM_RELOC_VANILLA: { // Mask in the target value a byte at a time (we don't have an alignment // guarantee for the target address, so this is safest). - uint8_t *p = (uint8_t*)Address; + uint8_t *p = (uint8_t*)LocalAddress; for (unsigned i = 0; i < Size; ++i) { *p++ = (uint8_t)Value; Value >>= 8; } break; } - case macho::RIT_ARM_Branch24Bit: { + case MachO::ARM_RELOC_BR24: { // Mask the value into the target address. We know instructions are // 32-bit aligned, so we can do it all at once. - uint32_t *p = (uint32_t*)Address; + uint32_t *p = (uint32_t*)LocalAddress; // The low two bits of the value are not encoded. Value >>= 2; // Mask the value to 24 bits. @@ -118,475 +308,146 @@ resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel, *p = (*p & ~0xffffff) | Value; break; } - case macho::RIT_ARM_ThumbBranch22Bit: - case macho::RIT_ARM_ThumbBranch32Bit: - case macho::RIT_ARM_Half: - case macho::RIT_ARM_HalfDifference: - case macho::RIT_Pair: - case macho::RIT_Difference: - case macho::RIT_ARM_LocalDifference: - case macho::RIT_ARM_PreboundLazyPointer: + case MachO::ARM_THUMB_RELOC_BR22: + case MachO::ARM_THUMB_32BIT_BRANCH: + case MachO::ARM_RELOC_HALF: + case MachO::ARM_RELOC_HALF_SECTDIFF: + case MachO::ARM_RELOC_PAIR: + case MachO::ARM_RELOC_SECTDIFF: + case MachO::ARM_RELOC_LOCAL_SECTDIFF: + case MachO::ARM_RELOC_PB_LA_PTR: return Error("Relocation type not implemented yet!"); } return false; } -bool RuntimeDyldMachO:: -loadSegment32(const MachOObject *Obj, - const MachOObject::LoadCommandInfo *SegmentLCI, - const InMemoryStruct &SymtabLC) { - // FIXME: This should really be combined w/ loadSegment64. Templatized - // function on the 32/64 datatypes maybe? - InMemoryStruct SegmentLC; - Obj->ReadSegmentLoadCommand(*SegmentLCI, SegmentLC); - if (!SegmentLC) - return Error("unable to load segment load command"); - - - SmallVector SectionMap; - for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) { - InMemoryStruct Sect; - Obj->ReadSection(*SegmentLCI, SectNum, Sect); - if (!Sect) - return Error("unable to load section: '" + Twine(SectNum) + "'"); - - // Allocate memory via the MM for the section. - uint8_t *Buffer; - uint32_t SectionID = Sections.size(); - if (Sect->Flags != 0x80000400) - Buffer = MemMgr->allocateCodeSection(Sect->Size, Sect->Align, SectionID); - else - Buffer = MemMgr->allocateDataSection(Sect->Size, Sect->Align, SectionID); - - DEBUG(dbgs() << "Loading " - << ((Sect->Flags == 0x80000400) ? "text" : "data") - << " (ID #" << SectionID << ")" - << " '" << Sect->SegmentName << "," - << Sect->Name << "' of size " << Sect->Size - << " to address " << Buffer << ".\n"); - - // Copy the payload from the object file into the allocated buffer. - uint8_t *Base = (uint8_t*)Obj->getData(SegmentLC->FileOffset, - SegmentLC->FileSize).data(); - memcpy(Buffer, Base + Sect->Address, Sect->Size); - - // Remember what got allocated for this SectionID. - Sections.push_back(sys::MemoryBlock(Buffer, Sect->Size)); - SectionLocalMemToID[Buffer] = SectionID; - - // By default, the load address of a section is its memory buffer. - SectionLoadAddress.push_back((uint64_t)Buffer); - - // Keep a map of object file section numbers to corresponding SectionIDs - // while processing the file. - SectionMap.push_back(SectionID); - } +void RuntimeDyldMachO::processRelocationRef(unsigned SectionID, + RelocationRef RelI, + ObjectImage &Obj, + ObjSectionToIDMap &ObjSectionToID, + const SymbolTableMap &Symbols, + StubMap &Stubs) { + const ObjectFile *OF = Obj.getObjectFile(); + const MachOObjectFile *MachO = static_cast(OF); + MachO::any_relocation_info RE= MachO->getRelocation(RelI.getRawDataRefImpl()); + + uint32_t RelType = MachO->getAnyRelocationType(RE); + + // FIXME: Properly handle scattered relocations. + // For now, optimistically skip these: they can often be ignored, as + // the static linker will already have applied the relocation, and it + // only needs to be reapplied if symbols move relative to one another. + // Note: This will fail horribly where the relocations *do* need to be + // applied, but that was already the case. + if (MachO->isRelocationScattered(RE)) + return; - // Process the symbol table. - SmallVector SymbolNames; - processSymbols32(Obj, SectionMap, SymbolNames, SymtabLC); - - // Process the relocations for each section we're loading. - Relocations.grow(Relocations.size() + SegmentLC->NumSections); - for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) { - InMemoryStruct Sect; - Obj->ReadSection(*SegmentLCI, SectNum, Sect); - if (!Sect) - return Error("unable to load section: '" + Twine(SectNum) + "'"); - for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) { - InMemoryStruct RE; - Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE); - if (RE->Word0 & macho::RF_Scattered) - return Error("NOT YET IMPLEMENTED: scattered relocations."); - // Word0 of the relocation is the offset into the section where the - // relocation should be applied. We need to translate that into an - // offset into a function since that's our atom. - uint32_t Offset = RE->Word0; - bool isExtern = (RE->Word1 >> 27) & 1; - - // FIXME: Get the relocation addend from the target address. - // FIXME: VERY imporant for internal relocations. - - // Figure out the source symbol of the relocation. If isExtern is true, - // this relocation references the symbol table, otherwise it references - // a section in the same object, numbered from 1 through NumSections - // (SectionBases is [0, NumSections-1]). - uint32_t SourceNum = RE->Word1 & 0xffffff; // 24-bit value - if (!isExtern) { - assert(SourceNum > 0 && "Invalid relocation section number!"); - unsigned SectionID = SectionMap[SourceNum - 1]; - unsigned TargetID = SectionMap[SectNum]; - DEBUG(dbgs() << "Internal relocation at Section #" - << TargetID << " + " << Offset - << " from Section #" - << SectionID << " (Word1: " - << format("0x%x", RE->Word1) << ")\n"); - - // Store the relocation information. It will get resolved when - // the section addresses are assigned. - Relocations[SectionID].push_back(RelocationEntry(TargetID, - Offset, - RE->Word1, - 0 /*Addend*/)); + RelocationValueRef Value; + SectionEntry &Section = Sections[SectionID]; + + bool isExtern = MachO->getPlainRelocationExternal(RE); + bool IsPCRel = MachO->getAnyRelocationPCRel(RE); + unsigned Size = MachO->getAnyRelocationLength(RE); + uint64_t Offset; + RelI.getOffset(Offset); + uint8_t *LocalAddress = Section.Address + Offset; + unsigned NumBytes = 1 << Size; + uint64_t Addend = 0; + memcpy(&Addend, LocalAddress, NumBytes); + + if (isExtern) { + // Obtain the symbol name which is referenced in the relocation + symbol_iterator Symbol = RelI.getSymbol(); + StringRef TargetName; + Symbol->getName(TargetName); + // First search for the symbol in the local symbol table + SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data()); + if (lsi != Symbols.end()) { + Value.SectionID = lsi->second.first; + Value.Addend = lsi->second.second + Addend; + } else { + // Search for the symbol in the global symbol table + SymbolTableMap::const_iterator gsi = GlobalSymbolTable.find(TargetName.data()); + if (gsi != GlobalSymbolTable.end()) { + Value.SectionID = gsi->second.first; + Value.Addend = gsi->second.second + Addend; } else { - StringRef SourceName = SymbolNames[SourceNum]; - - // Now store the relocation information. Associate it with the source - // symbol. Just add it to the unresolved list and let the general - // path post-load resolve it if we know where the symbol is. - UnresolvedRelocations[SourceName].push_back(RelocationEntry(SectNum, - Offset, - RE->Word1, - 0 /*Addend*/)); - DEBUG(dbgs() << "Relocation at Section #" << SectNum << " + " << Offset - << " from '" << SourceName << "(Word1: " - << format("0x%x", RE->Word1) << ")\n"); + Value.SymbolName = TargetName.data(); + Value.Addend = Addend; } } + } else { + SectionRef Sec = MachO->getRelocationSection(RE); + Value.SectionID = findOrEmitSection(Obj, Sec, true, ObjSectionToID); + uint64_t Addr; + Sec.getAddress(Addr); + Value.Addend = Addend - Addr; } - // Resolve the addresses of any symbols that were defined in this segment. - for (int i = 0, e = SymbolNames.size(); i != e; ++i) - resolveSymbol(SymbolNames[i]); - - return false; -} - - -bool RuntimeDyldMachO:: -loadSegment64(const MachOObject *Obj, - const MachOObject::LoadCommandInfo *SegmentLCI, - const InMemoryStruct &SymtabLC) { - InMemoryStruct Segment64LC; - Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC); - if (!Segment64LC) - return Error("unable to load segment load command"); - - - SmallVector SectionMap; - for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections; ++SectNum) { - InMemoryStruct Sect; - Obj->ReadSection64(*SegmentLCI, SectNum, Sect); - if (!Sect) - return Error("unable to load section: '" + Twine(SectNum) + "'"); - - // Allocate memory via the MM for the section. - uint8_t *Buffer; - uint32_t SectionID = Sections.size(); - if (Sect->Flags != 0x80000400) - Buffer = MemMgr->allocateCodeSection(Sect->Size, Sect->Align, SectionID); - else - Buffer = MemMgr->allocateDataSection(Sect->Size, Sect->Align, SectionID); - - DEBUG(dbgs() << "Loading " - << ((Sect->Flags == 0x80000400) ? "text" : "data") - << " (ID #" << SectionID << ")" - << " '" << Sect->SegmentName << "," - << Sect->Name << "' of size " << Sect->Size - << " to address " << Buffer << ".\n"); - - // Copy the payload from the object file into the allocated buffer. - uint8_t *Base = (uint8_t*)Obj->getData(Segment64LC->FileOffset, - Segment64LC->FileSize).data(); - memcpy(Buffer, Base + Sect->Address, Sect->Size); - - // Remember what got allocated for this SectionID. - Sections.push_back(sys::MemoryBlock(Buffer, Sect->Size)); - SectionLocalMemToID[Buffer] = SectionID; - - // By default, the load address of a section is its memory buffer. - SectionLoadAddress.push_back((uint64_t)Buffer); - - // Keep a map of object file section numbers to corresponding SectionIDs - // while processing the file. - SectionMap.push_back(SectionID); - } - - // Process the symbol table. - SmallVector SymbolNames; - processSymbols64(Obj, SectionMap, SymbolNames, SymtabLC); - - // Process the relocations for each section we're loading. - Relocations.grow(Relocations.size() + Segment64LC->NumSections); - for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections; ++SectNum) { - InMemoryStruct Sect; - Obj->ReadSection64(*SegmentLCI, SectNum, Sect); - if (!Sect) - return Error("unable to load section: '" + Twine(SectNum) + "'"); - for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) { - InMemoryStruct RE; - Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE); - if (RE->Word0 & macho::RF_Scattered) - return Error("NOT YET IMPLEMENTED: scattered relocations."); - // Word0 of the relocation is the offset into the section where the - // relocation should be applied. We need to translate that into an - // offset into a function since that's our atom. - uint32_t Offset = RE->Word0; - bool isExtern = (RE->Word1 >> 27) & 1; - - // FIXME: Get the relocation addend from the target address. - // FIXME: VERY imporant for internal relocations. - - // Figure out the source symbol of the relocation. If isExtern is true, - // this relocation references the symbol table, otherwise it references - // a section in the same object, numbered from 1 through NumSections - // (SectionBases is [0, NumSections-1]). - uint32_t SourceNum = RE->Word1 & 0xffffff; // 24-bit value - if (!isExtern) { - assert(SourceNum > 0 && "Invalid relocation section number!"); - unsigned SectionID = SectionMap[SourceNum - 1]; - unsigned TargetID = SectionMap[SectNum]; - DEBUG(dbgs() << "Internal relocation at Section #" - << TargetID << " + " << Offset - << " from Section #" - << SectionID << " (Word1: " - << format("0x%x", RE->Word1) << ")\n"); - - // Store the relocation information. It will get resolved when - // the section addresses are assigned. - Relocations[SectionID].push_back(RelocationEntry(TargetID, - Offset, - RE->Word1, - 0 /*Addend*/)); - } else { - StringRef SourceName = SymbolNames[SourceNum]; - - // Now store the relocation information. Associate it with the source - // symbol. Just add it to the unresolved list and let the general - // path post-load resolve it if we know where the symbol is. - UnresolvedRelocations[SourceName].push_back(RelocationEntry(SectNum, - Offset, - RE->Word1, - 0 /*Addend*/)); - DEBUG(dbgs() << "Relocation at Section #" << SectNum << " + " << Offset - << " from '" << SourceName << "(Word1: " - << format("0x%x", RE->Word1) << ")\n"); - } + if (Arch == Triple::x86_64 && (RelType == MachO::X86_64_RELOC_GOT || + RelType == MachO::X86_64_RELOC_GOT_LOAD)) { + assert(IsPCRel); + assert(Size == 2); + StubMap::const_iterator i = Stubs.find(Value); + uint8_t *Addr; + if (i != Stubs.end()) { + Addr = Section.Address + i->second; + } else { + Stubs[Value] = Section.StubOffset; + uint8_t *GOTEntry = Section.Address + Section.StubOffset; + RelocationEntry RE(SectionID, Section.StubOffset, + MachO::X86_64_RELOC_UNSIGNED, 0, false, 3); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + Section.StubOffset += 8; + Addr = GOTEntry; } - } - - // Resolve the addresses of any symbols that were defined in this segment. - for (int i = 0, e = SymbolNames.size(); i != e; ++i) - resolveSymbol(SymbolNames[i]); - - return false; -} - -bool RuntimeDyldMachO:: -processSymbols32(const MachOObject *Obj, - SmallVectorImpl &SectionMap, - SmallVectorImpl &SymbolNames, - const InMemoryStruct &SymtabLC) { - // FIXME: Combine w/ processSymbols64. Factor 64/32 datatype and such. - for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { - InMemoryStruct STE; - Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE); - if (!STE) - return Error("unable to read symbol: '" + Twine(i) + "'"); - // Get the symbol name. - StringRef Name = Obj->getStringAtIndex(STE->StringIndex); - SymbolNames.push_back(Name); - - // FIXME: Check the symbol type and flags. - if (STE->Type != 0xF) // external, defined in this segment. - continue; - // Flags in the upper nibble we don't care about. - if ((STE->Flags & 0xf) != 0x0) - continue; - - // Remember the symbol. - uint32_t SectionID = SectionMap[STE->SectionIndex - 1]; - SymbolTable[Name] = SymbolLoc(SectionID, STE->Value); - - DEBUG(dbgs() << "Symbol: '" << Name << "' @ " - << (getSectionAddress(SectionID) + STE->Value) - << "\n"); - } - return false; -} - -bool RuntimeDyldMachO:: -processSymbols64(const MachOObject *Obj, - SmallVectorImpl &SectionMap, - SmallVectorImpl &SymbolNames, - const InMemoryStruct &SymtabLC) { - for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { - InMemoryStruct STE; - Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE); - if (!STE) - return Error("unable to read symbol: '" + Twine(i) + "'"); - // Get the symbol name. - StringRef Name = Obj->getStringAtIndex(STE->StringIndex); - SymbolNames.push_back(Name); - - // FIXME: Check the symbol type and flags. - if (STE->Type != 0xF) // external, defined in this segment. - continue; - // Flags in the upper nibble we don't care about. - if ((STE->Flags & 0xf) != 0x0) - continue; - - // Remember the symbol. - uint32_t SectionID = SectionMap[STE->SectionIndex - 1]; - SymbolTable[Name] = SymbolLoc(SectionID, STE->Value); - - DEBUG(dbgs() << "Symbol: '" << Name << "' @ " - << (getSectionAddress(SectionID) + STE->Value) - << "\n"); - } - return false; -} - -// resolveSymbol - Resolve any relocations to the specified symbol if -// we know where it lives. -void RuntimeDyldMachO::resolveSymbol(StringRef Name) { - StringMap::const_iterator Loc = SymbolTable.find(Name); - if (Loc == SymbolTable.end()) - return; - - RelocationList &Relocs = UnresolvedRelocations[Name]; - DEBUG(dbgs() << "Resolving symbol '" << Name << "'\n"); - for (int i = 0, e = Relocs.size(); i != e; ++i) { - // Change the relocation to be section relative rather than symbol - // relative and move it to the resolved relocation list. - RelocationEntry Entry = Relocs[i]; - Entry.Addend += Loc->second.second; - Relocations[Loc->second.first].push_back(Entry); - } - // FIXME: Keep a worklist of the relocations we've added so that we can - // resolve more selectively later. - Relocs.clear(); -} - -bool RuntimeDyldMachO::loadObject(MemoryBuffer *InputBuffer) { - // If the linker is in an error state, don't do anything. - if (hasError()) - return true; - // Load the Mach-O wrapper object. - std::string ErrorStr; - OwningPtr Obj( - MachOObject::LoadFromBuffer(InputBuffer, &ErrorStr)); - if (!Obj) - return Error("unable to load object: '" + ErrorStr + "'"); - - // Get the CPU type information from the header. - const macho::Header &Header = Obj->getHeader(); - - // FIXME: Error checking that the loaded object is compatible with - // the system we're running on. - CPUType = Header.CPUType; - CPUSubtype = Header.CPUSubtype; - - // Validate that the load commands match what we expect. - const MachOObject::LoadCommandInfo *SegmentLCI = 0, *SymtabLCI = 0, - *DysymtabLCI = 0; - for (unsigned i = 0; i != Header.NumLoadCommands; ++i) { - const MachOObject::LoadCommandInfo &LCI = Obj->getLoadCommandInfo(i); - switch (LCI.Command.Type) { - case macho::LCT_Segment: - case macho::LCT_Segment64: - if (SegmentLCI) - return Error("unexpected input object (multiple segments)"); - SegmentLCI = &LCI; - break; - case macho::LCT_Symtab: - if (SymtabLCI) - return Error("unexpected input object (multiple symbol tables)"); - SymtabLCI = &LCI; - break; - case macho::LCT_Dysymtab: - if (DysymtabLCI) - return Error("unexpected input object (multiple symbol tables)"); - DysymtabLCI = &LCI; - break; - default: - return Error("unexpected input object (unexpected load command"); + resolveRelocation(Section, Offset, (uint64_t)Addr, + MachO::X86_64_RELOC_UNSIGNED, Value.Addend, true, 2); + } else if (Arch == Triple::arm && + (RelType & 0xf) == MachO::ARM_RELOC_BR24) { + // This is an ARM branch relocation, need to use a stub function. + + // Look up for existing stub. + StubMap::const_iterator i = Stubs.find(Value); + if (i != Stubs.end()) + resolveRelocation(Section, Offset, + (uint64_t)Section.Address + i->second, + RelType, 0, IsPCRel, Size); + else { + // Create a new stub function. + Stubs[Value] = Section.StubOffset; + uint8_t *StubTargetAddr = createStubFunction(Section.Address + + Section.StubOffset); + RelocationEntry RE(SectionID, StubTargetAddr - Section.Address, + MachO::GENERIC_RELOC_VANILLA, Value.Addend); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); + resolveRelocation(Section, Offset, + (uint64_t)Section.Address + Section.StubOffset, + RelType, 0, IsPCRel, Size); + Section.StubOffset += getMaxStubSize(); } - } - - if (!SymtabLCI) - return Error("no symbol table found in object"); - if (!SegmentLCI) - return Error("no segments found in object"); - - // Read and register the symbol table data. - InMemoryStruct SymtabLC; - Obj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC); - if (!SymtabLC) - return Error("unable to load symbol table load command"); - Obj->RegisterStringTable(*SymtabLC); - - // Read the dynamic link-edit information, if present (not present in static - // objects). - if (DysymtabLCI) { - InMemoryStruct DysymtabLC; - Obj->ReadDysymtabLoadCommand(*DysymtabLCI, DysymtabLC); - if (!DysymtabLC) - return Error("unable to load dynamic link-exit load command"); - - // FIXME: We don't support anything interesting yet. -// if (DysymtabLC->LocalSymbolsIndex != 0) -// return Error("NOT YET IMPLEMENTED: local symbol entries"); -// if (DysymtabLC->ExternalSymbolsIndex != 0) -// return Error("NOT YET IMPLEMENTED: non-external symbol entries"); -// if (DysymtabLC->UndefinedSymbolsIndex != SymtabLC->NumSymbolTableEntries) -// return Error("NOT YET IMPLEMENTED: undefined symbol entries"); - } - - // Load the segment load command. - if (SegmentLCI->Command.Type == macho::LCT_Segment) { - if (loadSegment32(Obj.get(), SegmentLCI, SymtabLC)) - return true; } else { - if (loadSegment64(Obj.get(), SegmentLCI, SymtabLC)) - return true; + RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, + IsPCRel, Size); + if (Value.SymbolName) + addRelocationForSymbol(RE, Value.SymbolName); + else + addRelocationForSection(RE, Value.SectionID); } - - // Assign the addresses of the sections from the object so that any - // relocations to them get set properly. - // FIXME: This is done directly from the client at the moment. We should - // default the values to the local storage, at least when the target arch - // is the same as the host arch. - - return false; } -// Assign an address to a symbol name and resolve all the relocations -// associated with it. -void RuntimeDyldMachO::reassignSectionAddress(unsigned SectionID, - uint64_t Addr) { - // The address to use for relocation resolution is not - // the address of the local section buffer. We must be doing - // a remote execution environment of some sort. Re-apply any - // relocations referencing this section with the given address. - // - // Addr is a uint64_t because we can't assume the pointer width - // of the target is the same as that of the host. Just use a generic - // "big enough" type. - - SectionLoadAddress[SectionID] = Addr; - - RelocationList &Relocs = Relocations[SectionID]; - for (unsigned i = 0, e = Relocs.size(); i != e; ++i) { - RelocationEntry &RE = Relocs[i]; - uint8_t *Target = (uint8_t*)Sections[RE.SectionID].base() + RE.Offset; - bool isPCRel = (RE.Data >> 24) & 1; - unsigned Type = (RE.Data >> 28) & 0xf; - unsigned Size = 1 << ((RE.Data >> 25) & 3); - - DEBUG(dbgs() << "Resolving relocation at Section #" << RE.SectionID - << " + " << RE.Offset << " (" << format("%p", Target) << ")" - << " from Section #" << SectionID << " (" << format("%p", Addr) << ")" - << "(" << (isPCRel ? "pcrel" : "absolute") - << ", type: " << Type << ", Size: " << Size << ", Addend: " - << RE.Addend << ").\n"); - - resolveRelocation(Target, Addr, isPCRel, Type, Size, RE.Addend); - } -} -bool RuntimeDyldMachO::isKnownFormat(const MemoryBuffer *InputBuffer) { - StringRef Magic = InputBuffer->getBuffer().slice(0, 4); +bool RuntimeDyldMachO::isCompatibleFormat( + const ObjectBuffer *InputBuffer) const { + if (InputBuffer->getBufferSize() < 4) + return false; + StringRef Magic(InputBuffer->getBufferStart(), 4); if (Magic == "\xFE\xED\xFA\xCE") return true; if (Magic == "\xCE\xFA\xED\xFE") return true; if (Magic == "\xFE\xED\xFA\xCF") return true; @@ -594,4 +455,9 @@ bool RuntimeDyldMachO::isKnownFormat(const MemoryBuffer *InputBuffer) { return false; } +bool RuntimeDyldMachO::isCompatibleFile( + const object::ObjectFile *Obj) const { + return Obj->isMachO(); +} + } // end namespace llvm