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[Mips64] Add support for MCJIT for MIPS64r2 and MIPS64r6
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Add support for resolving MIPS64r2 and MIPS64r6 relocations in MCJIT.

Patch by Vladimir Radosavljevic.

Differential Revision: http://reviews.llvm.org/D9667

llvm-svn: 238424
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@petar-jovanovic
petar-jovanovic committed May 28, 2015
1 parent fb7d5b8 commit 9720283
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Showing 32 changed files with 469 additions and 33 deletions.
3 changes: 2 additions & 1 deletion llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -149,6 +149,7 @@ RuntimeDyldImpl::loadObjectImpl(const object::ObjectFile &Obj) {
// Save information about our target
Arch = (Triple::ArchType)Obj.getArch();
IsTargetLittleEndian = Obj.isLittleEndian();
setMipsABI(Obj);

// Compute the memory size required to load all sections to be loaded
// and pass this information to the memory manager
Expand Down Expand Up @@ -689,7 +690,7 @@ uint8_t *RuntimeDyldImpl::createStubFunction(uint8_t *Addr,
// and stubs for branches Thumb - ARM and ARM - Thumb.
writeBytesUnaligned(0xe51ff004, Addr, 4); // ldr pc,<label>
return Addr + 4;
} else if (Arch == Triple::mipsel || Arch == Triple::mips) {
} else if (IsMipsO32ABI) {
// 0: 3c190000 lui t9,%hi(addr).
// 4: 27390000 addiu t9,t9,%lo(addr).
// 8: 03200008 jr t9.
Expand Down
253 changes: 247 additions & 6 deletions llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -507,6 +507,199 @@ void RuntimeDyldELF::resolveMIPSRelocation(const SectionEntry &Section,
}
}

void RuntimeDyldELF::setMipsABI(const ObjectFile &Obj) {
if (!StringRef(Triple::getArchTypePrefix(Arch)).equals("mips")) {
IsMipsO32ABI = false;
IsMipsN64ABI = false;
return;
}
unsigned AbiVariant;
Obj.getPlatformFlags(AbiVariant);
IsMipsO32ABI = AbiVariant & ELF::EF_MIPS_ABI_O32;
IsMipsN64ABI = Obj.getFileFormatName().equals("ELF64-mips");
if (AbiVariant & ELF::EF_MIPS_ABI2)
llvm_unreachable("Mips N32 ABI is not supported yet");
}

void RuntimeDyldELF::resolveMIPS64Relocation(const SectionEntry &Section,
uint64_t Offset, uint64_t Value,
uint32_t Type, int64_t Addend,
uint64_t SymOffset,
SID SectionID) {
uint32_t r_type = Type & 0xff;
uint32_t r_type2 = (Type >> 8) & 0xff;
uint32_t r_type3 = (Type >> 16) & 0xff;

// RelType is used to keep information for which relocation type we are
// applying relocation.
uint32_t RelType = r_type;
int64_t CalculatedValue = evaluateMIPS64Relocation(Section, Offset, Value,
RelType, Addend,
SymOffset, SectionID);
if (r_type2 != ELF::R_MIPS_NONE) {
RelType = r_type2;
CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
CalculatedValue, SymOffset,
SectionID);
}
if (r_type3 != ELF::R_MIPS_NONE) {
RelType = r_type3;
CalculatedValue = evaluateMIPS64Relocation(Section, Offset, 0, RelType,
CalculatedValue, SymOffset,
SectionID);
}
applyMIPS64Relocation(Section.Address + Offset, CalculatedValue, RelType);
}

int64_t
RuntimeDyldELF::evaluateMIPS64Relocation(const SectionEntry &Section,
uint64_t Offset, uint64_t Value,
uint32_t Type, int64_t Addend,
uint64_t SymOffset, SID SectionID) {

DEBUG(dbgs() << "evaluateMIPS64Relocation, LocalAddress: 0x"
<< format("%llx", Section.Address + Offset)
<< " FinalAddress: 0x"
<< format("%llx", Section.LoadAddress + Offset)
<< " Value: 0x" << format("%llx", Value) << " Type: 0x"
<< format("%x", Type) << " Addend: 0x" << format("%llx", Addend)
<< " SymOffset: " << format("%x", SymOffset)
<< "\n");

switch (Type) {
default:
llvm_unreachable("Not implemented relocation type!");
break;
case ELF::R_MIPS_JALR:
case ELF::R_MIPS_NONE:
break;
case ELF::R_MIPS_32:
case ELF::R_MIPS_64:
return Value + Addend;
case ELF::R_MIPS_26:
return ((Value + Addend) >> 2) & 0x3ffffff;
case ELF::R_MIPS_GPREL16: {
uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
return Value + Addend - (GOTAddr + 0x7ff0);
}
case ELF::R_MIPS_SUB:
return Value - Addend;
case ELF::R_MIPS_HI16:
// Get the higher 16-bits. Also add 1 if bit 15 is 1.
return ((Value + Addend + 0x8000) >> 16) & 0xffff;
case ELF::R_MIPS_LO16:
return (Value + Addend) & 0xffff;
case ELF::R_MIPS_CALL16:
case ELF::R_MIPS_GOT_DISP:
case ELF::R_MIPS_GOT_PAGE: {
uint8_t *LocalGOTAddr =
getSectionAddress(SectionToGOTMap[SectionID]) + SymOffset;
uint64_t GOTEntry = readBytesUnaligned(LocalGOTAddr, 8);

Value += Addend;
if (Type == ELF::R_MIPS_GOT_PAGE)
Value = (Value + 0x8000) & ~0xffff;

if (GOTEntry)
assert(GOTEntry == Value &&
"GOT entry has two different addresses.");
else
writeBytesUnaligned(Value, LocalGOTAddr, 8);

return (SymOffset - 0x7ff0) & 0xffff;
}
case ELF::R_MIPS_GOT_OFST: {
int64_t page = (Value + Addend + 0x8000) & ~0xffff;
return (Value + Addend - page) & 0xffff;
}
case ELF::R_MIPS_GPREL32: {
uint64_t GOTAddr = getSectionLoadAddress(SectionToGOTMap[SectionID]);
return Value + Addend - (GOTAddr + 0x7ff0);
}
case ELF::R_MIPS_PC16: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return ((Value + Addend - FinalAddress - 4) >> 2) & 0xffff;
}
case ELF::R_MIPS_PC18_S3: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return ((Value + Addend - ((FinalAddress | 7) ^ 7)) >> 3) & 0x3ffff;
}
case ELF::R_MIPS_PC19_S2: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return ((Value + Addend - FinalAddress) >> 2) & 0x7ffff;
}
case ELF::R_MIPS_PC21_S2: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return ((Value + Addend - FinalAddress) >> 2) & 0x1fffff;
}
case ELF::R_MIPS_PC26_S2: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return ((Value + Addend - FinalAddress) >> 2) & 0x3ffffff;
}
case ELF::R_MIPS_PCHI16: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return ((Value + Addend - FinalAddress + 0x8000) >> 16) & 0xffff;
}
case ELF::R_MIPS_PCLO16: {
uint64_t FinalAddress = (Section.LoadAddress + Offset);
return (Value + Addend - FinalAddress) & 0xffff;
}
}
return 0;
}

void RuntimeDyldELF::applyMIPS64Relocation(uint8_t *TargetPtr,
int64_t CalculatedValue,
uint32_t Type) {
uint32_t Insn = readBytesUnaligned(TargetPtr, 4);

switch (Type) {
default:
break;
case ELF::R_MIPS_32:
case ELF::R_MIPS_GPREL32:
writeBytesUnaligned(CalculatedValue & 0xffffffff, TargetPtr, 4);
break;
case ELF::R_MIPS_64:
case ELF::R_MIPS_SUB:
writeBytesUnaligned(CalculatedValue, TargetPtr, 8);
break;
case ELF::R_MIPS_26:
case ELF::R_MIPS_PC26_S2:
Insn = (Insn & 0xfc000000) | CalculatedValue;
writeBytesUnaligned(Insn, TargetPtr, 4);
break;
case ELF::R_MIPS_GPREL16:
Insn = (Insn & 0xffff0000) | (CalculatedValue & 0xffff);
writeBytesUnaligned(Insn, TargetPtr, 4);
break;
case ELF::R_MIPS_HI16:
case ELF::R_MIPS_LO16:
case ELF::R_MIPS_PCHI16:
case ELF::R_MIPS_PCLO16:
case ELF::R_MIPS_PC16:
case ELF::R_MIPS_CALL16:
case ELF::R_MIPS_GOT_DISP:
case ELF::R_MIPS_GOT_PAGE:
case ELF::R_MIPS_GOT_OFST:
Insn = (Insn & 0xffff0000) | CalculatedValue;
writeBytesUnaligned(Insn, TargetPtr, 4);
break;
case ELF::R_MIPS_PC18_S3:
Insn = (Insn & 0xfffc0000) | CalculatedValue;
writeBytesUnaligned(Insn, TargetPtr, 4);
break;
case ELF::R_MIPS_PC19_S2:
Insn = (Insn & 0xfff80000) | CalculatedValue;
writeBytesUnaligned(Insn, TargetPtr, 4);
break;
case ELF::R_MIPS_PC21_S2:
Insn = (Insn & 0xffe00000) | CalculatedValue;
writeBytesUnaligned(Insn, TargetPtr, 4);
break;
}
}

// Return the .TOC. section and offset.
void RuntimeDyldELF::findPPC64TOCSection(const ObjectFile &Obj,
ObjSectionToIDMap &LocalSections,
Expand Down Expand Up @@ -784,13 +977,13 @@ void RuntimeDyldELF::resolveRelocation(const RelocationEntry &RE,
uint64_t Value) {
const SectionEntry &Section = Sections[RE.SectionID];
return resolveRelocation(Section, RE.Offset, Value, RE.RelType, RE.Addend,
RE.SymOffset);
RE.SymOffset, RE.SectionID);
}

void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
uint64_t Offset, uint64_t Value,
uint32_t Type, int64_t Addend,
uint64_t SymOffset) {
uint64_t SymOffset, SID SectionID) {
switch (Arch) {
case Triple::x86_64:
resolveX86_64Relocation(Section, Offset, Value, Type, Addend, SymOffset);
Expand All @@ -812,8 +1005,16 @@ void RuntimeDyldELF::resolveRelocation(const SectionEntry &Section,
break;
case Triple::mips: // Fall through.
case Triple::mipsel:
resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL),
Type, (uint32_t)(Addend & 0xffffffffL));
case Triple::mips64:
case Triple::mips64el:
if (IsMipsO32ABI)
resolveMIPSRelocation(Section, Offset, (uint32_t)(Value & 0xffffffffL),
Type, (uint32_t)(Addend & 0xffffffffL));
else if (IsMipsN64ABI)
resolveMIPS64Relocation(Section, Offset, Value, Type, Addend, SymOffset,
SectionID);
else
llvm_unreachable("Mips ABI not handled");
break;
case Triple::ppc64: // Fall through.
case Triple::ppc64le:
Expand Down Expand Up @@ -999,7 +1200,7 @@ relocation_iterator RuntimeDyldELF::processRelocationRef(
}
processSimpleRelocation(SectionID, Offset, RelType, Value);
}
} else if ((Arch == Triple::mipsel || Arch == Triple::mips)) {
} else if (IsMipsO32ABI) {
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.
Expand Down Expand Up @@ -1054,6 +1255,23 @@ relocation_iterator RuntimeDyldELF::processRelocationRef(
Value.Addend += *Placeholder;
processSimpleRelocation(SectionID, Offset, RelType, Value);
}
} else if (IsMipsN64ABI) {
uint32_t r_type = RelType & 0xff;
RelocationEntry RE(SectionID, Offset, RelType, Value.Addend);
if (r_type == ELF::R_MIPS_CALL16 || r_type == ELF::R_MIPS_GOT_PAGE
|| r_type == ELF::R_MIPS_GOT_DISP) {
StringMap<uint64_t>::iterator i = GOTSymbolOffsets.find(TargetName);
if (i != GOTSymbolOffsets.end())
RE.SymOffset = i->second;
else {
RE.SymOffset = allocateGOTEntries(SectionID, 1);
GOTSymbolOffsets[TargetName] = RE.SymOffset;
}
}
if (Value.SymbolName)
addRelocationForSymbol(RE, Value.SymbolName);
else
addRelocationForSection(RE, Value.SectionID);
} else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
if (RelType == ELF::R_PPC64_REL24) {
// Determine ABI variant in use for this object.
Expand Down Expand Up @@ -1356,9 +1574,18 @@ size_t RuntimeDyldELF::getGOTEntrySize() {
case Triple::x86:
case Triple::arm:
case Triple::thumb:
Result = sizeof(uint32_t);
break;
case Triple::mips:
case Triple::mipsel:
Result = sizeof(uint32_t);
case Triple::mips64:
case Triple::mips64el:
if (IsMipsO32ABI)
Result = sizeof(uint32_t);
else if (IsMipsN64ABI)
Result = sizeof(uint64_t);
else
llvm_unreachable("Mips ABI not handled");
break;
default:
llvm_unreachable("Unsupported CPU type!");
Expand Down Expand Up @@ -1413,6 +1640,20 @@ void RuntimeDyldELF::finalizeLoad(const ObjectFile &Obj,
// For now, initialize all GOT entries to zero. We'll fill them in as
// needed when GOT-based relocations are applied.
memset(Addr, 0, TotalSize);
if (IsMipsN64ABI) {
// To correctly resolve Mips GOT relocations, we need a mapping from
// object's sections to GOTs.
for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
SI != SE; ++SI) {
if (SI->relocation_begin() != SI->relocation_end()) {
section_iterator RelocatedSection = SI->getRelocatedSection();
ObjSectionToIDMap::iterator i = SectionMap.find(*RelocatedSection);
assert (i != SectionMap.end());
SectionToGOTMap[i->second] = GOTSectionID;
}
}
GOTSymbolOffsets.clear();
}
}

// Look for and record the EH frame section.
Expand Down
25 changes: 23 additions & 2 deletions llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -25,7 +25,7 @@ class RuntimeDyldELF : public RuntimeDyldImpl {

void resolveRelocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend,
uint64_t SymOffset = 0);
uint64_t SymOffset = 0, SID SectionID = 0);

void resolveX86_64Relocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend,
Expand All @@ -49,12 +49,24 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
void resolveSystemZRelocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend);

void resolveMIPS64Relocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend,
uint64_t SymOffset, SID SectionID);

int64_t evaluateMIPS64Relocation(const SectionEntry &Section,
uint64_t Offset, uint64_t Value,
uint32_t Type, int64_t Addend,
uint64_t SymOffset, SID SectionID);

void applyMIPS64Relocation(uint8_t *TargetPtr, int64_t CalculatedValue,
uint32_t Type);

unsigned getMaxStubSize() override {
if (Arch == Triple::aarch64 || Arch == Triple::aarch64_be)
return 20; // movz; movk; movk; movk; br
if (Arch == Triple::arm || Arch == Triple::thumb)
return 8; // 32-bit instruction and 32-bit address
else if (Arch == Triple::mipsel || Arch == Triple::mips)
else if (IsMipsO32ABI)
return 16;
else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le)
return 44;
Expand All @@ -73,6 +85,8 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
return 1;
}

void setMipsABI(const ObjectFile &Obj) override;

void findPPC64TOCSection(const ObjectFile &Obj,
ObjSectionToIDMap &LocalSections,
RelocationValueRef &Rel);
Expand Down Expand Up @@ -114,6 +128,13 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
// that consume more than one slot)
unsigned CurrentGOTIndex;

// A map from section to a GOT section that has entries for section's GOT
// relocations. (Mips64 specific)
DenseMap<SID, SID> SectionToGOTMap;

// A map to avoid duplicate got entries (Mips64 specific)
StringMap<uint64_t> GOTSymbolOffsets;

// When a module is loaded we save the SectionID of the EH frame section
// in a table until we receive a request to register all unregistered
// EH frame sections with the memory manager.
Expand Down
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