namespace {
+static inline
+error_code check(error_code Err) {
+ if (Err) {
+ report_fatal_error(Err.message());
+ }
+ return Err;
+}
+
template<support::endianness target_endianness, bool is64Bits>
class DyldELFObject : public ELFObjectFile<target_endianness, is64Bits> {
LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits)
const ELFObjectFile<target_endianness, is64Bits> *v) {
return v->isDyldType();
}
- static inline bool classof(const DyldELFObject *v) {
- return true;
- }
};
template<support::endianness target_endianness, bool is64Bits>
RuntimeDyldELF::~RuntimeDyldELF() {
}
-void RuntimeDyldELF::resolveX86_64Relocation(uint8_t *LocalAddress,
- uint64_t FinalAddress,
+void RuntimeDyldELF::resolveX86_64Relocation(const SectionEntry &Section,
+ uint64_t Offset,
uint64_t Value,
uint32_t Type,
int64_t Addend) {
llvm_unreachable("Relocation type not implemented yet!");
break;
case ELF::R_X86_64_64: {
- uint64_t *Target = (uint64_t*)(LocalAddress);
+ uint64_t *Target = reinterpret_cast<uint64_t*>(Section.Address + Offset);
*Target = Value + Addend;
+ DEBUG(dbgs() << "Writing " << format("%p", (Value + Addend))
+ << " at " << format("%p\n",Target));
break;
}
case ELF::R_X86_64_32:
(Type == ELF::R_X86_64_32S &&
((int64_t)Value <= INT32_MAX && (int64_t)Value >= INT32_MIN)));
uint32_t TruncatedAddr = (Value & 0xFFFFFFFF);
- uint32_t *Target = reinterpret_cast<uint32_t*>(LocalAddress);
+ uint32_t *Target = reinterpret_cast<uint32_t*>(Section.Address + Offset);
*Target = TruncatedAddr;
+ DEBUG(dbgs() << "Writing " << format("%p", TruncatedAddr)
+ << " at " << format("%p\n",Target));
break;
}
case ELF::R_X86_64_PC32: {
- uint32_t *Placeholder = reinterpret_cast<uint32_t*>(LocalAddress);
+ // Get the placeholder value from the generated object since
+ // a previous relocation attempt may have overwritten the loaded version
+ uint32_t *Placeholder = reinterpret_cast<uint32_t*>(Section.ObjAddress
+ + Offset);
+ uint32_t *Target = reinterpret_cast<uint32_t*>(Section.Address + Offset);
+ uint64_t FinalAddress = Section.LoadAddress + Offset;
int64_t RealOffset = *Placeholder + Value + Addend - FinalAddress;
assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
- *Placeholder = TruncOffset;
+ *Target = TruncOffset;
break;
}
}
}
-void RuntimeDyldELF::resolveX86Relocation(uint8_t *LocalAddress,
- uint32_t FinalAddress,
+void RuntimeDyldELF::resolveX86Relocation(const SectionEntry &Section,
+ uint64_t Offset,
uint32_t Value,
uint32_t Type,
int32_t Addend) {
switch (Type) {
case ELF::R_386_32: {
- uint32_t *Target = (uint32_t*)(LocalAddress);
- uint32_t Placeholder = *Target;
- *Target = Placeholder + Value + Addend;
+ // Get the placeholder value from the generated object since
+ // a previous relocation attempt may have overwritten the loaded version
+ uint32_t *Placeholder = reinterpret_cast<uint32_t*>(Section.ObjAddress
+ + Offset);
+ uint32_t *Target = reinterpret_cast<uint32_t*>(Section.Address + Offset);
+ *Target = *Placeholder + Value + Addend;
break;
}
case ELF::R_386_PC32: {
- uint32_t *Placeholder = reinterpret_cast<uint32_t*>(LocalAddress);
+ // Get the placeholder value from the generated object since
+ // a previous relocation attempt may have overwritten the loaded version
+ uint32_t *Placeholder = reinterpret_cast<uint32_t*>(Section.ObjAddress
+ + Offset);
+ uint32_t *Target = reinterpret_cast<uint32_t*>(Section.Address + Offset);
+ uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
uint32_t RealOffset = *Placeholder + Value + Addend - FinalAddress;
- *Placeholder = RealOffset;
+ *Target = RealOffset;
break;
}
default:
}
}
-void RuntimeDyldELF::resolveARMRelocation(uint8_t *LocalAddress,
- uint32_t FinalAddress,
+void RuntimeDyldELF::resolveARMRelocation(const SectionEntry &Section,
+ uint64_t Offset,
uint32_t Value,
uint32_t Type,
int32_t Addend) {
// TODO: Add Thumb relocations.
- uint32_t* TargetPtr = (uint32_t*)LocalAddress;
+ uint32_t* TargetPtr = (uint32_t*)(Section.Address + Offset);
+ uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
Value += Addend;
- DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: " << LocalAddress
+ DEBUG(dbgs() << "resolveARMRelocation, LocalAddress: "
+ << Section.Address + Offset
<< " FinalAddress: " << format("%p",FinalAddress)
<< " Value: " << format("%x",Value)
<< " Type: " << format("%x",Type)
}
}
-void RuntimeDyldELF::resolveMIPSRelocation(uint8_t *LocalAddress,
- uint32_t FinalAddress,
+void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
+ uint64_t Offset,
uint32_t Value,
uint32_t Type,
int32_t Addend) {
- uint32_t* TargetPtr = (uint32_t*)LocalAddress;
+ uint32_t* TargetPtr = (uint32_t*)(Section.Address + Offset);
Value += Addend;
- DEBUG(dbgs() << "resolveMipselocation, LocalAddress: " << LocalAddress
- << " FinalAddress: " << format("%p",FinalAddress)
+ DEBUG(dbgs() << "resolveMipselocation, LocalAddress: "
+ << Section.Address + Offset
+ << " FinalAddress: "
+ << format("%p",Section.LoadAddress + Offset)
<< " Value: " << format("%x",Value)
<< " Type: " << format("%x",Type)
<< " Addend: " << format("%x",Addend)
}
}
-void RuntimeDyldELF::resolveRelocation(uint8_t *LocalAddress,
- uint64_t FinalAddress,
+// Return the .TOC. section address to R_PPC64_TOC relocations.
+uint64_t RuntimeDyldELF::findPPC64TOC() const {
+ // The TOC consists of sections .got, .toc, .tocbss, .plt in that
+ // order. The TOC starts where the first of these sections starts.
+ SectionList::const_iterator it = Sections.begin();
+ SectionList::const_iterator ite = Sections.end();
+ for (; it != ite; ++it) {
+ if (it->Name == ".got" ||
+ it->Name == ".toc" ||
+ it->Name == ".tocbss" ||
+ it->Name == ".plt")
+ break;
+ }
+ if (it == ite) {
+ // This may happen for
+ // * references to TOC base base (sym@toc, .odp relocation) without
+ // a .toc directive.
+ // In this case just use the first section (which is usually
+ // the .odp) since the code won't reference the .toc base
+ // directly.
+ it = Sections.begin();
+ }
+ assert (it != ite);
+ // Per the ppc64-elf-linux ABI, The TOC base is TOC value plus 0x8000
+ // thus permitting a full 64 Kbytes segment.
+ return it->LoadAddress + 0x8000;
+}
+
+// Returns the sections and offset associated with the ODP entry referenced
+// by Symbol.
+void RuntimeDyldELF::findOPDEntrySection(ObjectImage &Obj,
+ ObjSectionToIDMap &LocalSections,
+ RelocationValueRef &Rel) {
+ // Get the ELF symbol value (st_value) to compare with Relocation offset in
+ // .opd entries
+
+ error_code err;
+ for (section_iterator si = Obj.begin_sections(),
+ se = Obj.end_sections(); si != se; si.increment(err)) {
+ StringRef SectionName;
+ check(si->getName(SectionName));
+ if (SectionName != ".opd")
+ continue;
+
+ for (relocation_iterator i = si->begin_relocations(),
+ e = si->end_relocations(); i != e;) {
+ check(err);
+
+ // The R_PPC64_ADDR64 relocation indicates the first field
+ // of a .opd entry
+ uint64_t TypeFunc;
+ check(i->getType(TypeFunc));
+ if (TypeFunc != ELF::R_PPC64_ADDR64) {
+ i.increment(err);
+ continue;
+ }
+
+ SymbolRef TargetSymbol;
+ uint64_t TargetSymbolOffset;
+ int64_t TargetAdditionalInfo;
+ check(i->getSymbol(TargetSymbol));
+ check(i->getOffset(TargetSymbolOffset));
+ check(i->getAdditionalInfo(TargetAdditionalInfo));
+
+ i = i.increment(err);
+ if (i == e)
+ break;
+ check(err);
+
+ // Just check if following relocation is a R_PPC64_TOC
+ uint64_t TypeTOC;
+ check(i->getType(TypeTOC));
+ if (TypeTOC != ELF::R_PPC64_TOC)
+ continue;
+
+ // Finally compares the Symbol value and the target symbol offset
+ // to check if this .opd entry refers to the symbol the relocation
+ // points to.
+ if (Rel.Addend != (intptr_t)TargetSymbolOffset)
+ continue;
+
+ section_iterator tsi(Obj.end_sections());
+ check(TargetSymbol.getSection(tsi));
+ Rel.SectionID = findOrEmitSection(Obj, (*tsi), true, LocalSections);
+ Rel.Addend = (intptr_t)TargetAdditionalInfo;
+ return;
+ }
+ }
+ llvm_unreachable("Attempting to get address of ODP entry!");
+}
+
+// Relocation masks following the #lo(value), #hi(value), #higher(value),
+// and #highest(value) macros defined in section 4.5.1. Relocation Types
+// in PPC-elf64abi document.
+//
+static inline
+uint16_t applyPPClo (uint64_t value)
+{
+ return value & 0xffff;
+}
+
+static inline
+uint16_t applyPPChi (uint64_t value)
+{
+ return (value >> 16) & 0xffff;
+}
+
+static inline
+uint16_t applyPPChigher (uint64_t value)
+{
+ return (value >> 32) & 0xffff;
+}
+
+static inline
+uint16_t applyPPChighest (uint64_t value)
+{
+ return (value >> 48) & 0xffff;
+}
+
+void RuntimeDyldELF::resolvePPC64Relocation(const SectionEntry &Section,
+ uint64_t Offset,
+ uint64_t Value,
+ uint32_t Type,
+ int64_t Addend) {
+ uint8_t* LocalAddress = Section.Address + Offset;
+ switch (Type) {
+ default:
+ llvm_unreachable("Relocation type not implemented yet!");
+ break;
+ case ELF::R_PPC64_ADDR16_LO :
+ writeInt16BE(LocalAddress, applyPPClo (Value + Addend));
+ break;
+ case ELF::R_PPC64_ADDR16_HI :
+ writeInt16BE(LocalAddress, applyPPChi (Value + Addend));
+ break;
+ case ELF::R_PPC64_ADDR16_HIGHER :
+ writeInt16BE(LocalAddress, applyPPChigher (Value + Addend));
+ break;
+ case ELF::R_PPC64_ADDR16_HIGHEST :
+ writeInt16BE(LocalAddress, applyPPChighest (Value + Addend));
+ break;
+ case ELF::R_PPC64_ADDR14 : {
+ assert(((Value + Addend) & 3) == 0);
+ // Preserve the AA/LK bits in the branch instruction
+ uint8_t aalk = *(LocalAddress+3);
+ writeInt16BE(LocalAddress + 2, (aalk & 3) | ((Value + Addend) & 0xfffc));
+ } break;
+ case ELF::R_PPC64_REL24 : {
+ uint64_t FinalAddress = (Section.LoadAddress + Offset);
+ int32_t delta = static_cast<int32_t>(Value - FinalAddress + Addend);
+ if (SignExtend32<24>(delta) != delta)
+ llvm_unreachable("Relocation R_PPC64_REL24 overflow");
+ // Generates a 'bl <address>' instruction
+ writeInt32BE(LocalAddress, 0x48000001 | (delta & 0x03FFFFFC));
+ } break;
+ case ELF::R_PPC64_ADDR64 :
+ writeInt64BE(LocalAddress, Value + Addend);
+ break;
+ case ELF::R_PPC64_TOC :
+ writeInt64BE(LocalAddress, findPPC64TOC());
+ break;
+ case ELF::R_PPC64_TOC16 : {
+ uint64_t TOCStart = findPPC64TOC();
+ Value = applyPPClo((Value + Addend) - TOCStart);
+ writeInt16BE(LocalAddress, applyPPClo(Value));
+ } break;
+ case ELF::R_PPC64_TOC16_DS : {
+ uint64_t TOCStart = findPPC64TOC();
+ Value = ((Value + Addend) - TOCStart);
+ writeInt16BE(LocalAddress, applyPPClo(Value));
+ } break;
+ }
+}
+
+
+void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
+ uint64_t Offset,
uint64_t Value,
uint32_t Type,
int64_t Addend) {
switch (Arch) {
case Triple::x86_64:
- resolveX86_64Relocation(LocalAddress, FinalAddress, Value, Type, Addend);
+ resolveX86_64Relocation(Section, Offset, Value, Type, Addend);
break;
case Triple::x86:
- resolveX86Relocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ resolveX86Relocation(Section, Offset,
(uint32_t)(Value & 0xffffffffL), Type,
(uint32_t)(Addend & 0xffffffffL));
break;
case Triple::arm: // Fall through.
case Triple::thumb:
- resolveARMRelocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ resolveARMRelocation(Section, Offset,
(uint32_t)(Value & 0xffffffffL), Type,
(uint32_t)(Addend & 0xffffffffL));
break;
case Triple::mips: // Fall through.
case Triple::mipsel:
- resolveMIPSRelocation(LocalAddress, (uint32_t)(FinalAddress & 0xffffffffL),
+ resolveMIPSRelocation(Section, Offset,
(uint32_t)(Value & 0xffffffffL), Type,
(uint32_t)(Addend & 0xffffffffL));
break;
+ case Triple::ppc64:
+ resolvePPC64Relocation(Section, Offset, Value, Type, Addend);
+ break;
default: llvm_unreachable("Unsupported CPU type!");
}
}
RelocationValueRef Value;
// First search for the symbol in the local symbol table
SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
+ SymbolRef::Type SymType;
+ Symbol.getType(SymType);
if (lsi != Symbols.end()) {
Value.SectionID = lsi->second.first;
Value.Addend = lsi->second.second;
Value.SectionID = gsi->second.first;
Value.Addend = gsi->second.second;
} else {
- SymbolRef::Type SymType;
- Symbol.getType(SymType);
switch (SymType) {
case SymbolRef::ST_Debug: {
// TODO: Now ELF SymbolRef::ST_Debug = STT_SECTION, it's not obviously
if (si == Obj.end_sections())
llvm_unreachable("Symbol section not found, bad object file format!");
DEBUG(dbgs() << "\t\tThis is section symbol\n");
- Value.SectionID = findOrEmitSection(Obj, (*si), true, ObjSectionToID);
+ // Default to 'true' in case isText fails (though it never does).
+ bool isCode = true;
+ si->isText(isCode);
+ Value.SectionID = findOrEmitSection(Obj,
+ (*si),
+ isCode,
+ ObjSectionToID);
Value.Addend = Addend;
break;
}
// This is an ARM branch relocation, need to use a stub function.
DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
SectionEntry &Section = Sections[Rel.SectionID];
- uint8_t *Target = Section.Address + Rel.Offset;
- // Look up for existing stub.
+ // Look for an existing stub.
StubMap::const_iterator i = Stubs.find(Value);
if (i != Stubs.end()) {
- resolveRelocation(Target, (uint64_t)Target, (uint64_t)Section.Address +
- i->second, RelType, 0);
+ resolveRelocation(Section, Rel.Offset,
+ (uint64_t)Section.Address + i->second, RelType, 0);
DEBUG(dbgs() << " Stub function found\n");
} else {
// Create a new stub function.
else
addRelocationForSection(RE, Value.SectionID);
- resolveRelocation(Target, (uint64_t)Target, (uint64_t)Section.Address +
- Section.StubOffset, RelType, 0);
+ resolveRelocation(Section, Rel.Offset,
+ (uint64_t)Section.Address + Section.StubOffset,
+ RelType, 0);
Section.StubOffset += getMaxStubSize();
}
} else if (Arch == Triple::mipsel && RelType == ELF::R_MIPS_26) {
// Look up for existing stub.
StubMap::const_iterator i = Stubs.find(Value);
if (i != Stubs.end()) {
- resolveRelocation(Target, (uint64_t)Target,
- (uint64_t)Section.Address +
- i->second, RelType, 0);
+ resolveRelocation(Section, Rel.Offset,
+ (uint64_t)Section.Address + i->second, RelType, 0);
DEBUG(dbgs() << " Stub function found\n");
} else {
// Create a new stub function.
addRelocationForSection(RELo, Value.SectionID);
}
- resolveRelocation(Target, (uint64_t)Target,
- (uint64_t)Section.Address +
- Section.StubOffset, RelType, 0);
+ resolveRelocation(Section, Rel.Offset,
+ (uint64_t)Section.Address + Section.StubOffset,
+ RelType, 0);
Section.StubOffset += getMaxStubSize();
}
+ } else if (Arch == Triple::ppc64) {
+ if (RelType == ELF::R_PPC64_REL24) {
+ // A PPC branch relocation will need a stub function if the target is
+ // an external symbol (Symbol::ST_Unknown) or if the target address
+ // is not within the signed 24-bits branch address.
+ SectionEntry &Section = Sections[Rel.SectionID];
+ uint8_t *Target = Section.Address + Rel.Offset;
+ bool RangeOverflow = false;
+ if (SymType != SymbolRef::ST_Unknown) {
+ // A function call may points to the .opd entry, so the final symbol value
+ // in calculated based in the relocation values in .opd section.
+ findOPDEntrySection(Obj, ObjSectionToID, Value);
+ uint8_t *RelocTarget = Sections[Value.SectionID].Address + Value.Addend;
+ int32_t delta = static_cast<int32_t>(Target - RelocTarget);
+ // If it is within 24-bits branch range, just set the branch target
+ if (SignExtend32<24>(delta) == delta) {
+ RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend);
+ if (Value.SymbolName)
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+ } else {
+ RangeOverflow = true;
+ }
+ }
+ if (SymType == SymbolRef::ST_Unknown || RangeOverflow == true) {
+ // It is an external symbol (SymbolRef::ST_Unknown) or within a range
+ // larger than 24-bits.
+ StubMap::const_iterator i = Stubs.find(Value);
+ if (i != Stubs.end()) {
+ // Symbol function stub already created, just relocate to it
+ resolveRelocation(Section, Rel.Offset,
+ (uint64_t)Section.Address + i->second, RelType, 0);
+ DEBUG(dbgs() << " Stub function found\n");
+ } else {
+ // Create a new stub function.
+ DEBUG(dbgs() << " Create a new stub function\n");
+ Stubs[Value] = Section.StubOffset;
+ uint8_t *StubTargetAddr = createStubFunction(Section.Address +
+ Section.StubOffset);
+ RelocationEntry RE(Rel.SectionID, StubTargetAddr - Section.Address,
+ ELF::R_PPC64_ADDR64, Value.Addend);
+
+ // Generates the 64-bits address loads as exemplified in section
+ // 4.5.1 in PPC64 ELF ABI.
+ RelocationEntry REhst(Rel.SectionID,
+ StubTargetAddr - Section.Address + 2,
+ ELF::R_PPC64_ADDR16_HIGHEST, Value.Addend);
+ RelocationEntry REhr(Rel.SectionID,
+ StubTargetAddr - Section.Address + 6,
+ ELF::R_PPC64_ADDR16_HIGHER, Value.Addend);
+ RelocationEntry REh(Rel.SectionID,
+ StubTargetAddr - Section.Address + 14,
+ ELF::R_PPC64_ADDR16_HI, Value.Addend);
+ RelocationEntry REl(Rel.SectionID,
+ StubTargetAddr - Section.Address + 18,
+ ELF::R_PPC64_ADDR16_LO, Value.Addend);
+
+ if (Value.SymbolName) {
+ addRelocationForSymbol(REhst, Value.SymbolName);
+ addRelocationForSymbol(REhr, Value.SymbolName);
+ addRelocationForSymbol(REh, Value.SymbolName);
+ addRelocationForSymbol(REl, Value.SymbolName);
+ } else {
+ addRelocationForSection(REhst, Value.SectionID);
+ addRelocationForSection(REhr, Value.SectionID);
+ addRelocationForSection(REh, Value.SectionID);
+ addRelocationForSection(REl, Value.SectionID);
+ }
+
+ resolveRelocation(Section, Rel.Offset,
+ (uint64_t)Section.Address + Section.StubOffset,
+ RelType, 0);
+ if (SymType == SymbolRef::ST_Unknown)
+ // Restore the TOC for external calls
+ writeInt32BE(Target+4, 0xE8410028); // ld r2,40(r1)
+ Section.StubOffset += getMaxStubSize();
+ }
+ }
+ } else {
+ RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend);
+ // Extra check to avoid relocation againt empty symbols (usually
+ // the R_PPC64_TOC).
+ if (Value.SymbolName && !TargetName.empty())
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+ }
} else {
RelocationEntry RE(Rel.SectionID, Rel.Offset, RelType, Value.Addend);
if (Value.SymbolName)
}
}
+unsigned RuntimeDyldELF::getCommonSymbolAlignment(const SymbolRef &Sym) {
+ // In ELF, the value of an SHN_COMMON symbol is its alignment requirement.
+ uint64_t Align;
+ Check(Sym.getValue(Align));
+ return Align;
+}
+
bool RuntimeDyldELF::isCompatibleFormat(const ObjectBuffer *Buffer) const {
if (Buffer->getBufferSize() < strlen(ELF::ElfMagic))
return false;