break;
}
case ELF::R_X86_64_PC32: {
- // Get the placeholder value from the generated object since
- // a previous relocation attempt may have overwritten the loaded version
- support::ulittle32_t::ref Placeholder(
- (void *)(Section.ObjAddress + Offset));
uint64_t FinalAddress = Section.LoadAddress + Offset;
int64_t RealOffset = Value + Addend - FinalAddress;
- // Don't add the placeholder if this is a stub
- if (Offset < Section.Size)
- RealOffset += Placeholder;
assert(RealOffset <= INT32_MAX && RealOffset >= INT32_MIN);
int32_t TruncOffset = (RealOffset & 0xFFFFFFFF);
support::ulittle32_t::ref(Section.Address + Offset) = TruncOffset;
break;
}
case ELF::R_X86_64_PC64: {
- // Get the placeholder value from the generated object since
- // a previous relocation attempt may have overwritten the loaded version
- support::ulittle64_t::ref Placeholder(
- (void *)(Section.ObjAddress + Offset));
uint64_t FinalAddress = Section.LoadAddress + Offset;
int64_t RealOffset = Value + Addend - FinalAddress;
- if (Offset < Section.Size)
- RealOffset += Placeholder;
support::ulittle64_t::ref(Section.Address + Offset) = RealOffset;
break;
}
uint32_t Type, int32_t Addend) {
switch (Type) {
case ELF::R_386_32: {
- // Get the placeholder value from the generated object since
- // a previous relocation attempt may have overwritten the loaded version
- support::ulittle32_t::ref Placeholder(
- (void *)(Section.ObjAddress + Offset));
- support::ulittle32_t::ref(Section.Address + Offset) =
- Placeholder + Value + Addend;
+ support::ulittle32_t::ref(Section.Address + Offset) = Value + Addend;
break;
}
case ELF::R_386_PC32: {
- // Get the placeholder value from the generated object since
- // a previous relocation attempt may have overwritten the loaded version
- support::ulittle32_t::ref Placeholder(
- (void *)(Section.ObjAddress + Offset));
uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
- uint32_t RealOffset = Placeholder + Value + Addend - FinalAddress;
+ uint32_t RealOffset = Value + Addend - FinalAddress;
support::ulittle32_t::ref(Section.Address + Offset) = RealOffset;
break;
}
uint64_t Offset, uint32_t Value,
uint32_t Type, int32_t Addend) {
// TODO: Add Thumb relocations.
- uint32_t *Placeholder =
- reinterpret_cast<uint32_t *>(Section.ObjAddress + Offset);
uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset);
uint32_t FinalAddress = ((Section.LoadAddress + Offset) & 0xFFFFFFFF);
Value += Addend;
case ELF::R_ARM_NONE:
break;
- // Write a 32bit value to relocation address, taking into account the
- // implicit addend encoded in the target.
case ELF::R_ARM_PREL31:
case ELF::R_ARM_TARGET1:
case ELF::R_ARM_ABS32:
- *TargetPtr = *Placeholder + Value;
+ *TargetPtr = Value;
break;
- // Write first 16 bit of 32 bit value to the mov instruction.
- // Last 4 bit should be shifted.
+ // Write first 16 bit of 32 bit value to the mov instruction.
+ // Last 4 bit should be shifted.
case ELF::R_ARM_MOVW_ABS_NC:
- // We are not expecting any other addend in the relocation address.
- // Using 0x000F0FFF because MOVW has its 16 bit immediate split into 2
- // non-contiguous fields.
- assert((*Placeholder & 0x000F0FFF) == 0);
- Value = Value & 0xFFFF;
- *TargetPtr = *Placeholder | (Value & 0xFFF);
- *TargetPtr |= ((Value >> 12) & 0xF) << 16;
- break;
- // Write last 16 bit of 32 bit value to the mov instruction.
- // Last 4 bit should be shifted.
case ELF::R_ARM_MOVT_ABS:
- // We are not expecting any other addend in the relocation address.
- // Use 0x000F0FFF for the same reason as R_ARM_MOVW_ABS_NC.
- assert((*Placeholder & 0x000F0FFF) == 0);
-
- Value = (Value >> 16) & 0xFFFF;
- *TargetPtr = *Placeholder | (Value & 0xFFF);
+ if (Type == ELF::R_ARM_MOVW_ABS_NC)
+ Value = Value & 0xFFFF;
+ else if (Type == ELF::R_ARM_MOVT_ABS)
+ Value = (Value >> 16) & 0xFFFF;
+ *TargetPtr &= ~0x000F0FFF;
+ *TargetPtr = Value & 0xFFF;
*TargetPtr |= ((Value >> 12) & 0xF) << 16;
break;
- // Write 24 bit relative value to the branch instruction.
+ // Write 24 bit relative value to the branch instruction.
case ELF::R_ARM_PC24: // Fall through.
case ELF::R_ARM_CALL: // Fall through.
- case ELF::R_ARM_JUMP24: {
+ case ELF::R_ARM_JUMP24:
int32_t RelValue = static_cast<int32_t>(Value - FinalAddress - 8);
RelValue = (RelValue & 0x03FFFFFC) >> 2;
assert((*TargetPtr & 0xFFFFFF) == 0xFFFFFE);
*TargetPtr |= RelValue;
break;
}
- case ELF::R_ARM_PRIVATE_0:
- // This relocation is reserved by the ARM ELF ABI for internal use. We
- // appropriate it here to act as an R_ARM_ABS32 without any addend for use
- // in the stubs created during JIT (which can't put an addend into the
- // original object file).
- *TargetPtr = Value;
- break;
- }
}
void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
uint64_t Offset, uint32_t Value,
uint32_t Type, int32_t Addend) {
- uint32_t *Placeholder =
- reinterpret_cast<uint32_t *>(Section.ObjAddress + Offset);
uint32_t *TargetPtr = (uint32_t *)(Section.Address + Offset);
Value += Addend;
llvm_unreachable("Not implemented relocation type!");
break;
case ELF::R_MIPS_32:
- *TargetPtr = Value + (*Placeholder);
+ *TargetPtr = Value;
break;
case ELF::R_MIPS_26:
- *TargetPtr = ((*Placeholder) & 0xfc000000) | ((Value & 0x0fffffff) >> 2);
+ *TargetPtr = ((*TargetPtr) & 0xfc000000) | ((Value & 0x0fffffff) >> 2);
break;
case ELF::R_MIPS_HI16:
// Get the higher 16-bits. Also add 1 if bit 15 is 1.
- Value += ((*Placeholder) & 0x0000ffff) << 16;
*TargetPtr =
- ((*Placeholder) & 0xffff0000) | (((Value + 0x8000) >> 16) & 0xffff);
+ ((*TargetPtr) & 0xffff0000) | (((Value + 0x8000) >> 16) & 0xffff);
break;
case ELF::R_MIPS_LO16:
- Value += ((*Placeholder) & 0x0000ffff);
- *TargetPtr = ((*Placeholder) & 0xffff0000) | (Value & 0xffff);
- break;
- case ELF::R_MIPS_UNUSED1:
- // Similar to ELF::R_ARM_PRIVATE_0, R_MIPS_UNUSED1 and R_MIPS_UNUSED2
- // are used for internal JIT purpose. These relocations are similar to
- // R_MIPS_HI16 and R_MIPS_LO16, but they do not take any addend into
- // account.
- *TargetPtr =
- ((*TargetPtr) & 0xffff0000) | (((Value + 0x8000) >> 16) & 0xffff);
- break;
- case ELF::R_MIPS_UNUSED2:
*TargetPtr = ((*TargetPtr) & 0xffff0000) | (Value & 0xffff);
break;
}
}
}
+void *RuntimeDyldELF::computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const {
+ return (void*)(Sections[SectionID].ObjAddress + Offset);
+}
+
+void RuntimeDyldELF::processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value) {
+ RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
+ if (Value.SymbolName)
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+}
+
relocation_iterator RuntimeDyldELF::processRelocationRef(
unsigned SectionID, relocation_iterator RelI,
const ObjectFile &Obj,
0);
Section.StubOffset += getMaxStubSize();
}
- } else if (Arch == Triple::arm &&
- (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
- RelType == ELF::R_ARM_JUMP24)) {
- // This is an ARM branch relocation, need to use a stub function.
- DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
- SectionEntry &Section = Sections[SectionID];
+ } else if (Arch == Triple::arm) {
+ if (RelType == ELF::R_ARM_PC24 || RelType == ELF::R_ARM_CALL ||
+ RelType == ELF::R_ARM_JUMP24) {
+ // This is an ARM branch relocation, need to use a stub function.
+ DEBUG(dbgs() << "\t\tThis is an ARM branch relocation.");
+ SectionEntry &Section = Sections[SectionID];
- // Look for an existing stub.
- StubMap::const_iterator i = Stubs.find(Value);
- if (i != Stubs.end()) {
- resolveRelocation(Section, 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 =
+ // Look for an existing stub.
+ StubMap::const_iterator i = Stubs.find(Value);
+ if (i != Stubs.end()) {
+ resolveRelocation(Section, 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(SectionID, StubTargetAddr - Section.Address,
- ELF::R_ARM_PRIVATE_0, 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);
- Section.StubOffset += getMaxStubSize();
+ RelocationEntry RE(SectionID, StubTargetAddr - Section.Address,
+ ELF::R_ARM_ABS32, 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);
+ Section.StubOffset += getMaxStubSize();
+ }
+ } else {
+ uint32_t *Placeholder =
+ reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
+ if (RelType == ELF::R_ARM_PREL31 || RelType == ELF::R_ARM_TARGET1 ||
+ RelType == ELF::R_ARM_ABS32) {
+ Value.Addend += *Placeholder;
+ } else if (RelType == ELF::R_ARM_MOVW_ABS_NC || RelType == ELF::R_ARM_MOVT_ABS) {
+ // See ELF for ARM documentation
+ Value.Addend += (int16_t)((*Placeholder & 0xFFF) | (((*Placeholder >> 16) & 0xF) << 12));
+ }
+ processSimpleRelocation(SectionID, Offset, RelType, Value);
}
- } else if ((Arch == Triple::mipsel || Arch == Triple::mips) &&
- RelType == ELF::R_MIPS_26) {
- // This is an Mips branch relocation, need to use a stub function.
- DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
- SectionEntry &Section = Sections[SectionID];
- uint8_t *Target = Section.Address + Offset;
- uint32_t *TargetAddress = (uint32_t *)Target;
+ } else if ((Arch == Triple::mipsel || Arch == Triple::mips)) {
+ uint32_t *Placeholder = reinterpret_cast<uint32_t*>(computePlaceholderAddress(SectionID, Offset));
+ if (RelType == ELF::R_MIPS_26) {
+ // This is an Mips branch relocation, need to use a stub function.
+ DEBUG(dbgs() << "\t\tThis is a Mips branch relocation.");
+ SectionEntry &Section = Sections[SectionID];
- // Extract the addend from the instruction.
- uint32_t Addend = ((*TargetAddress) & 0x03ffffff) << 2;
+ // Extract the addend from the instruction.
+ // We shift up by two since the Value will be down shifted again
+ // when applying the relocation.
+ uint32_t Addend = ((*Placeholder) & 0x03ffffff) << 2;
- Value.Addend += Addend;
+ Value.Addend += Addend;
- // Look up for existing stub.
- StubMap::const_iterator i = Stubs.find(Value);
- if (i != Stubs.end()) {
- RelocationEntry RE(SectionID, Offset, RelType, i->second);
- addRelocationForSection(RE, SectionID);
- 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 =
+ // Look up for existing stub.
+ StubMap::const_iterator i = Stubs.find(Value);
+ if (i != Stubs.end()) {
+ RelocationEntry RE(SectionID, Offset, RelType, i->second);
+ addRelocationForSection(RE, SectionID);
+ 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);
- // Creating Hi and Lo relocations for the filled stub instructions.
- RelocationEntry REHi(SectionID, StubTargetAddr - Section.Address,
- ELF::R_MIPS_UNUSED1, Value.Addend);
- RelocationEntry RELo(SectionID, StubTargetAddr - Section.Address + 4,
- ELF::R_MIPS_UNUSED2, Value.Addend);
+ // Creating Hi and Lo relocations for the filled stub instructions.
+ RelocationEntry REHi(SectionID, StubTargetAddr - Section.Address,
+ ELF::R_MIPS_HI16, Value.Addend);
+ RelocationEntry RELo(SectionID, StubTargetAddr - Section.Address + 4,
+ ELF::R_MIPS_LO16, Value.Addend);
- if (Value.SymbolName) {
- addRelocationForSymbol(REHi, Value.SymbolName);
- addRelocationForSymbol(RELo, Value.SymbolName);
- } else {
- addRelocationForSection(REHi, Value.SectionID);
- addRelocationForSection(RELo, Value.SectionID);
- }
+ if (Value.SymbolName) {
+ addRelocationForSymbol(REHi, Value.SymbolName);
+ addRelocationForSymbol(RELo, Value.SymbolName);
+ }
+ else {
+ addRelocationForSection(REHi, Value.SectionID);
+ addRelocationForSection(RELo, Value.SectionID);
+ }
- RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset);
- addRelocationForSection(RE, SectionID);
- Section.StubOffset += getMaxStubSize();
+ RelocationEntry RE(SectionID, Offset, RelType, Section.StubOffset);
+ addRelocationForSection(RE, SectionID);
+ Section.StubOffset += getMaxStubSize();
+ }
+ } else {
+ if (RelType == ELF::R_MIPS_HI16)
+ Value.Addend += ((*Placeholder) & 0x0000ffff) << 16;
+ else if (RelType == ELF::R_MIPS_LO16)
+ Value.Addend += ((*Placeholder) & 0x0000ffff);
+ processSimpleRelocation(SectionID, Offset, RelType, Value);
}
} else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
if (RelType == ELF::R_PPC64_REL24) {
Addend);
else
resolveRelocation(Section, Offset, StubAddress, RelType, Addend);
- } else if (Arch == Triple::x86_64 && RelType == ELF::R_X86_64_PLT32) {
- // The way the PLT relocations normally work is that the linker allocates
- // the
- // PLT and this relocation makes a PC-relative call into the PLT. The PLT
- // entry will then jump to an address provided by the GOT. On first call,
- // the
- // GOT address will point back into PLT code that resolves the symbol. After
- // the first call, the GOT entry points to the actual function.
- //
- // For local functions we're ignoring all of that here and just replacing
- // the PLT32 relocation type with PC32, which will translate the relocation
- // into a PC-relative call directly to the function. For external symbols we
- // can't be sure the function will be within 2^32 bytes of the call site, so
- // we need to create a stub, which calls into the GOT. This case is
- // equivalent to the usual PLT implementation except that we use the stub
- // mechanism in RuntimeDyld (which puts stubs at the end of the section)
- // rather than allocating a PLT section.
- if (Value.SymbolName) {
- // This is a call to an external function.
- // Look for an existing stub.
- SectionEntry &Section = Sections[SectionID];
- StubMap::const_iterator i = Stubs.find(Value);
- uintptr_t StubAddress;
- if (i != Stubs.end()) {
+ } else if (Arch == Triple::x86_64) {
+ if (RelType == ELF::R_X86_64_PLT32) {
+ // The way the PLT relocations normally work is that the linker allocates
+ // the
+ // PLT and this relocation makes a PC-relative call into the PLT. The PLT
+ // entry will then jump to an address provided by the GOT. On first call,
+ // the
+ // GOT address will point back into PLT code that resolves the symbol. After
+ // the first call, the GOT entry points to the actual function.
+ //
+ // For local functions we're ignoring all of that here and just replacing
+ // the PLT32 relocation type with PC32, which will translate the relocation
+ // into a PC-relative call directly to the function. For external symbols we
+ // can't be sure the function will be within 2^32 bytes of the call site, so
+ // we need to create a stub, which calls into the GOT. This case is
+ // equivalent to the usual PLT implementation except that we use the stub
+ // mechanism in RuntimeDyld (which puts stubs at the end of the section)
+ // rather than allocating a PLT section.
+ if (Value.SymbolName) {
+ // This is a call to an external function.
+ // Look for an existing stub.
+ SectionEntry &Section = Sections[SectionID];
+ StubMap::const_iterator i = Stubs.find(Value);
+ uintptr_t StubAddress;
+ if (i != Stubs.end()) {
StubAddress = uintptr_t(Section.Address) + i->second;
DEBUG(dbgs() << " Stub function found\n");
- } else {
+ } else {
// Create a new stub function (equivalent to a PLT entry).
DEBUG(dbgs() << " Create a new stub function\n");
uintptr_t BaseAddress = uintptr_t(Section.Address);
uintptr_t StubAlignment = getStubAlignment();
StubAddress = (BaseAddress + Section.StubOffset + StubAlignment - 1) &
- -StubAlignment;
+ -StubAlignment;
unsigned StubOffset = StubAddress - BaseAddress;
Stubs[Value] = StubOffset;
createStubFunction((uint8_t *)StubAddress);
// Fill in the value of the symbol we're targeting into the GOT
addRelocationForSymbol(computeGOTOffsetRE(SectionID,GOTOffset,0,ELF::R_X86_64_64),
- Value.SymbolName);
+ Value.SymbolName);
+ }
+
+ // Make the target call a call into the stub table.
+ resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
+ Addend);
+ } else {
+ RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
+ Value.Offset);
+ addRelocationForSection(RE, Value.SectionID);
}
+ } else if (RelType == ELF::R_X86_64_GOTPCREL) {
+ uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
+ resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend);
- // Make the target call a call into the stub table.
- resolveRelocation(Section, Offset, StubAddress, ELF::R_X86_64_PC32,
- Addend);
+ // Fill in the value of the symbol we're targeting into the GOT
+ RelocationEntry RE = computeGOTOffsetRE(SectionID, GOTOffset, Value.Offset, ELF::R_X86_64_64);
+ if (Value.SymbolName)
+ addRelocationForSymbol(RE, Value.SymbolName);
+ else
+ addRelocationForSection(RE, Value.SectionID);
+ } else if (RelType == ELF::R_X86_64_PC32) {
+ Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
+ processSimpleRelocation(SectionID, Offset, RelType, Value);
+ } else if (RelType == ELF::R_X86_64_PC64) {
+ Value.Addend += support::ulittle64_t::ref(computePlaceholderAddress(SectionID, Offset));
+ processSimpleRelocation(SectionID, Offset, RelType, Value);
} else {
- RelocationEntry RE(SectionID, Offset, ELF::R_X86_64_PC32, Value.Addend,
- Value.Offset);
- addRelocationForSection(RE, Value.SectionID);
+ processSimpleRelocation(SectionID, Offset, RelType, Value);
}
- } else if (Arch == Triple::x86_64 && RelType == ELF::R_X86_64_GOTPCREL) {
- uint64_t GOTOffset = allocateGOTEntries(SectionID, 1);
- resolveGOTOffsetRelocation(SectionID, Offset, GOTOffset + Addend);
-
- // Fill in the value of the symbol we're targeting into the GOT
- RelocationEntry RE = computeGOTOffsetRE(SectionID, GOTOffset, Value.Offset, ELF::R_X86_64_64);
- if (Value.SymbolName)
- addRelocationForSymbol(RE, Value.SymbolName);
- else
- addRelocationForSection(RE, Value.SectionID);
} else {
- RelocationEntry RE(SectionID, Offset, RelType, Value.Addend, Value.Offset);
- if (Value.SymbolName)
- addRelocationForSymbol(RE, Value.SymbolName);
- else
- addRelocationForSection(RE, Value.SectionID);
+ if (Arch == Triple::x86) {
+ Value.Addend += support::ulittle32_t::ref(computePlaceholderAddress(SectionID, Offset));
+ }
+ processSimpleRelocation(SectionID, Offset, RelType, Value);
}
return ++RelI;
}
projects / oota-llvm.git / commitdiff