//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "dyld"
+#include "RuntimeDyldMachO.h"
#include "llvm/ADT/OwningPtr.h"
-#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/STLExtras.h"
-#include "RuntimeDyldMachO.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;
+}
+
+StringRef RuntimeDyldMachO::getEHFrameSection() {
+ SectionEntry *Text = NULL;
+ SectionEntry *EHFrame = NULL;
+ SectionEntry *ExceptTab = NULL;
+ for (int i = 0, e = Sections.size(); i != e; ++i) {
+ if (Sections[i].Name == "__eh_frame")
+ EHFrame = &Sections[i];
+ else if (Sections[i].Name == "__text")
+ Text = &Sections[i];
+ else if (Sections[i].Name == "__gcc_except_tab")
+ ExceptTab = &Sections[i];
+ }
+ if (Text == NULL || EHFrame == NULL)
+ return StringRef();
+
+ 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);
+
+ return StringRef((char*)EHFrame->Address, EHFrame->Size);
+}
+
+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) {
+ switch (Arch) {
default: llvm_unreachable("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);
+ 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;
+ }
+}
+
+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::RIT_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::RIT_Difference:
+ case macho::RIT_Generic_LocalDifference:
+ case macho::RIT_Generic_PreboundLazyPointer:
+ return Error("Relocation type not implemented yet!");
}
}
-bool RuntimeDyldMachO::
-resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
- unsigned Type, unsigned Size, int64_t Addend) {
+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:
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;
}
}
-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.
case macho::RIT_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;
case macho::RIT_ARM_Branch24Bit: {
// 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.
return false;
}
-bool RuntimeDyldMachO::
-loadSegment32(const MachOObject *Obj,
- const MachOObject::LoadCommandInfo *SegmentLCI,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
- // FIXME: This should really be combined w/ loadSegment64. Templatized
- // function on the 32/64 datatypes maybe?
- InMemoryStruct<macho::SegmentLoadCommand> SegmentLC;
- Obj->ReadSegmentLoadCommand(*SegmentLCI, SegmentLC);
- if (!SegmentLC)
- return Error("unable to load segment load command");
-
-
- SmallVector<unsigned, 16> SectionMap;
- for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) {
- InMemoryStruct<macho::Section> 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<const MachOObjectFile*>(OF);
+ macho::RelocationEntry 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<StringRef, 64> 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<macho::Section> 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<macho::RelocationEntry> 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<macho::SymtabLoadCommand> &SymtabLC) {
- InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
- Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC);
- if (!Segment64LC)
- return Error("unable to load segment load command");
-
-
- SmallVector<unsigned, 16> SectionMap;
- for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections; ++SectNum) {
- InMemoryStruct<macho::Section64> 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();
- unsigned Align = 1 << Sect->Align; // .o file has log2 alignment.
- if (Sect->Flags == 0x80000400)
- Buffer = MemMgr->allocateCodeSection(Sect->Size, Align, SectionID);
- else
- Buffer = MemMgr->allocateDataSection(Sect->Size, Align, SectionID);
-
- DEBUG(dbgs() << "Loading "
- << ((Sect->Flags == 0x80000400) ? "text" : "data")
- << " (ID #" << SectionID << ")"
- << " '" << Sect->SegmentName << ","
- << Sect->Name << "' of size " << Sect->Size
- << " (align " << Align << ")"
- << " 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<StringRef, 64> 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<macho::Section64> 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<macho::RelocationEntry> 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::RIT_X86_64_GOT) {
+ 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::RIT_X86_64_Unsigned, Value.Addend - 4, 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<unsigned> &SectionMap,
- SmallVectorImpl<StringRef> &SymbolNames,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
- // FIXME: Combine w/ processSymbols64. Factor 64/32 datatype and such.
- for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
- InMemoryStruct<macho::SymbolTableEntry> 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<unsigned> &SectionMap,
- SmallVectorImpl<StringRef> &SymbolNames,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
- for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
- InMemoryStruct<macho::Symbol64TableEntry> 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<SymbolLoc>::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<MachOObject> 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::RIT_X86_64_Unsigned, 4, true, 2);
+ } else if (Arch == Triple::arm &&
+ (RelType & 0xf) == macho::RIT_ARM_Branch24Bit) {
+ // 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::RIT_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<macho::SymtabLoadCommand> 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<macho::DysymtabLoadCommand> 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;