diff options
Diffstat (limited to 'contrib/llvm-project/llvm/lib/Object/XCOFFObjectFile.cpp')
-rw-r--r-- | contrib/llvm-project/llvm/lib/Object/XCOFFObjectFile.cpp | 788 |
1 files changed, 788 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/Object/XCOFFObjectFile.cpp b/contrib/llvm-project/llvm/lib/Object/XCOFFObjectFile.cpp new file mode 100644 index 000000000000..f98cd69a0d37 --- /dev/null +++ b/contrib/llvm-project/llvm/lib/Object/XCOFFObjectFile.cpp @@ -0,0 +1,788 @@ +//===--- XCOFFObjectFile.cpp - XCOFF object file implementation -----------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file defines the XCOFFObjectFile class. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Object/XCOFFObjectFile.h" +#include <cstddef> +#include <cstring> + +namespace llvm { +namespace object { + +enum { FUNCTION_SYM = 0x20, SYM_TYPE_MASK = 0x07, RELOC_OVERFLOW = 65535 }; + +// Checks that [Ptr, Ptr + Size) bytes fall inside the memory buffer +// 'M'. Returns a pointer to the underlying object on success. +template <typename T> +static Expected<const T *> getObject(MemoryBufferRef M, const void *Ptr, + const uint64_t Size = sizeof(T)) { + uintptr_t Addr = uintptr_t(Ptr); + if (std::error_code EC = Binary::checkOffset(M, Addr, Size)) + return errorCodeToError(EC); + return reinterpret_cast<const T *>(Addr); +} + +static uintptr_t getWithOffset(uintptr_t Base, ptrdiff_t Offset) { + return reinterpret_cast<uintptr_t>(reinterpret_cast<const char *>(Base) + + Offset); +} + +template <typename T> static const T *viewAs(uintptr_t in) { + return reinterpret_cast<const T *>(in); +} + +static StringRef generateXCOFFFixedNameStringRef(const char *Name) { + auto NulCharPtr = + static_cast<const char *>(memchr(Name, '\0', XCOFF::NameSize)); + return NulCharPtr ? StringRef(Name, NulCharPtr - Name) + : StringRef(Name, XCOFF::NameSize); +} + +template <typename T> StringRef XCOFFSectionHeader<T>::getName() const { + const T &DerivedXCOFFSectionHeader = static_cast<const T &>(*this); + return generateXCOFFFixedNameStringRef(DerivedXCOFFSectionHeader.Name); +} + +template <typename T> uint16_t XCOFFSectionHeader<T>::getSectionType() const { + const T &DerivedXCOFFSectionHeader = static_cast<const T &>(*this); + return DerivedXCOFFSectionHeader.Flags & SectionFlagsTypeMask; +} + +template <typename T> +bool XCOFFSectionHeader<T>::isReservedSectionType() const { + return getSectionType() & SectionFlagsReservedMask; +} + +bool XCOFFRelocation32::isRelocationSigned() const { + return Info & XR_SIGN_INDICATOR_MASK; +} + +bool XCOFFRelocation32::isFixupIndicated() const { + return Info & XR_FIXUP_INDICATOR_MASK; +} + +uint8_t XCOFFRelocation32::getRelocatedLength() const { + // The relocation encodes the bit length being relocated minus 1. Add back + // the 1 to get the actual length being relocated. + return (Info & XR_BIASED_LENGTH_MASK) + 1; +} + +void XCOFFObjectFile::checkSectionAddress(uintptr_t Addr, + uintptr_t TableAddress) const { + if (Addr < TableAddress) + report_fatal_error("Section header outside of section header table."); + + uintptr_t Offset = Addr - TableAddress; + if (Offset >= getSectionHeaderSize() * getNumberOfSections()) + report_fatal_error("Section header outside of section header table."); + + if (Offset % getSectionHeaderSize() != 0) + report_fatal_error( + "Section header pointer does not point to a valid section header."); +} + +const XCOFFSectionHeader32 * +XCOFFObjectFile::toSection32(DataRefImpl Ref) const { + assert(!is64Bit() && "32-bit interface called on 64-bit object file."); +#ifndef NDEBUG + checkSectionAddress(Ref.p, getSectionHeaderTableAddress()); +#endif + return viewAs<XCOFFSectionHeader32>(Ref.p); +} + +const XCOFFSectionHeader64 * +XCOFFObjectFile::toSection64(DataRefImpl Ref) const { + assert(is64Bit() && "64-bit interface called on a 32-bit object file."); +#ifndef NDEBUG + checkSectionAddress(Ref.p, getSectionHeaderTableAddress()); +#endif + return viewAs<XCOFFSectionHeader64>(Ref.p); +} + +const XCOFFSymbolEntry *XCOFFObjectFile::toSymbolEntry(DataRefImpl Ref) const { + assert(!is64Bit() && "Symbol table support not implemented for 64-bit."); + assert(Ref.p != 0 && "Symbol table pointer can not be nullptr!"); +#ifndef NDEBUG + checkSymbolEntryPointer(Ref.p); +#endif + auto SymEntPtr = viewAs<XCOFFSymbolEntry>(Ref.p); + return SymEntPtr; +} + +const XCOFFFileHeader32 *XCOFFObjectFile::fileHeader32() const { + assert(!is64Bit() && "32-bit interface called on 64-bit object file."); + return static_cast<const XCOFFFileHeader32 *>(FileHeader); +} + +const XCOFFFileHeader64 *XCOFFObjectFile::fileHeader64() const { + assert(is64Bit() && "64-bit interface called on a 32-bit object file."); + return static_cast<const XCOFFFileHeader64 *>(FileHeader); +} + +const XCOFFSectionHeader32 * +XCOFFObjectFile::sectionHeaderTable32() const { + assert(!is64Bit() && "32-bit interface called on 64-bit object file."); + return static_cast<const XCOFFSectionHeader32 *>(SectionHeaderTable); +} + +const XCOFFSectionHeader64 * +XCOFFObjectFile::sectionHeaderTable64() const { + assert(is64Bit() && "64-bit interface called on a 32-bit object file."); + return static_cast<const XCOFFSectionHeader64 *>(SectionHeaderTable); +} + +void XCOFFObjectFile::moveSymbolNext(DataRefImpl &Symb) const { + const XCOFFSymbolEntry *SymEntPtr = toSymbolEntry(Symb); + SymEntPtr += SymEntPtr->NumberOfAuxEntries + 1; +#ifndef NDEBUG + // This function is used by basic_symbol_iterator, which allows to + // point to the end-of-symbol-table address. + if (reinterpret_cast<uintptr_t>(SymEntPtr) != getEndOfSymbolTableAddress()) + checkSymbolEntryPointer(reinterpret_cast<uintptr_t>(SymEntPtr)); +#endif + Symb.p = reinterpret_cast<uintptr_t>(SymEntPtr); +} + +Expected<StringRef> +XCOFFObjectFile::getStringTableEntry(uint32_t Offset) const { + // The byte offset is relative to the start of the string table. + // A byte offset value of 0 is a null or zero-length symbol + // name. A byte offset in the range 1 to 3 (inclusive) points into the length + // field; as a soft-error recovery mechanism, we treat such cases as having an + // offset of 0. + if (Offset < 4) + return StringRef(nullptr, 0); + + if (StringTable.Data != nullptr && StringTable.Size > Offset) + return (StringTable.Data + Offset); + + return make_error<GenericBinaryError>("Bad offset for string table entry", + object_error::parse_failed); +} + +Expected<StringRef> +XCOFFObjectFile::getCFileName(const XCOFFFileAuxEnt *CFileEntPtr) const { + if (CFileEntPtr->NameInStrTbl.Magic != + XCOFFSymbolEntry::NAME_IN_STR_TBL_MAGIC) + return generateXCOFFFixedNameStringRef(CFileEntPtr->Name); + return getStringTableEntry(CFileEntPtr->NameInStrTbl.Offset); +} + +Expected<StringRef> XCOFFObjectFile::getSymbolName(DataRefImpl Symb) const { + const XCOFFSymbolEntry *SymEntPtr = toSymbolEntry(Symb); + + // A storage class value with the high-order bit on indicates that the name is + // a symbolic debugger stabstring. + if (SymEntPtr->StorageClass & 0x80) + return StringRef("Unimplemented Debug Name"); + + if (SymEntPtr->NameInStrTbl.Magic != XCOFFSymbolEntry::NAME_IN_STR_TBL_MAGIC) + return generateXCOFFFixedNameStringRef(SymEntPtr->SymbolName); + + return getStringTableEntry(SymEntPtr->NameInStrTbl.Offset); +} + +Expected<uint64_t> XCOFFObjectFile::getSymbolAddress(DataRefImpl Symb) const { + assert(!is64Bit() && "Symbol table support not implemented for 64-bit."); + return toSymbolEntry(Symb)->Value; +} + +uint64_t XCOFFObjectFile::getSymbolValueImpl(DataRefImpl Symb) const { + assert(!is64Bit() && "Symbol table support not implemented for 64-bit."); + return toSymbolEntry(Symb)->Value; +} + +uint64_t XCOFFObjectFile::getCommonSymbolSizeImpl(DataRefImpl Symb) const { + uint64_t Result = 0; + llvm_unreachable("Not yet implemented!"); + return Result; +} + +Expected<SymbolRef::Type> +XCOFFObjectFile::getSymbolType(DataRefImpl Symb) const { + llvm_unreachable("Not yet implemented!"); + return SymbolRef::ST_Other; +} + +Expected<section_iterator> +XCOFFObjectFile::getSymbolSection(DataRefImpl Symb) const { + const XCOFFSymbolEntry *SymEntPtr = toSymbolEntry(Symb); + int16_t SectNum = SymEntPtr->SectionNumber; + + if (isReservedSectionNumber(SectNum)) + return section_end(); + + Expected<DataRefImpl> ExpSec = getSectionByNum(SectNum); + if (!ExpSec) + return ExpSec.takeError(); + + return section_iterator(SectionRef(ExpSec.get(), this)); +} + +void XCOFFObjectFile::moveSectionNext(DataRefImpl &Sec) const { + const char *Ptr = reinterpret_cast<const char *>(Sec.p); + Sec.p = reinterpret_cast<uintptr_t>(Ptr + getSectionHeaderSize()); +} + +Expected<StringRef> XCOFFObjectFile::getSectionName(DataRefImpl Sec) const { + return generateXCOFFFixedNameStringRef(getSectionNameInternal(Sec)); +} + +uint64_t XCOFFObjectFile::getSectionAddress(DataRefImpl Sec) const { + // Avoid ternary due to failure to convert the ubig32_t value to a unit64_t + // with MSVC. + if (is64Bit()) + return toSection64(Sec)->VirtualAddress; + + return toSection32(Sec)->VirtualAddress; +} + +uint64_t XCOFFObjectFile::getSectionIndex(DataRefImpl Sec) const { + // Section numbers in XCOFF are numbered beginning at 1. A section number of + // zero is used to indicate that a symbol is being imported or is undefined. + if (is64Bit()) + return toSection64(Sec) - sectionHeaderTable64() + 1; + else + return toSection32(Sec) - sectionHeaderTable32() + 1; +} + +uint64_t XCOFFObjectFile::getSectionSize(DataRefImpl Sec) const { + // Avoid ternary due to failure to convert the ubig32_t value to a unit64_t + // with MSVC. + if (is64Bit()) + return toSection64(Sec)->SectionSize; + + return toSection32(Sec)->SectionSize; +} + +Expected<ArrayRef<uint8_t>> +XCOFFObjectFile::getSectionContents(DataRefImpl Sec) const { + if (isSectionVirtual(Sec)) + return ArrayRef<uint8_t>(); + + uint64_t OffsetToRaw; + if (is64Bit()) + OffsetToRaw = toSection64(Sec)->FileOffsetToRawData; + else + OffsetToRaw = toSection32(Sec)->FileOffsetToRawData; + + const uint8_t * ContentStart = base() + OffsetToRaw; + uint64_t SectionSize = getSectionSize(Sec); + if (checkOffset(Data, uintptr_t(ContentStart), SectionSize)) + return make_error<BinaryError>(); + + return makeArrayRef(ContentStart,SectionSize); +} + +uint64_t XCOFFObjectFile::getSectionAlignment(DataRefImpl Sec) const { + uint64_t Result = 0; + llvm_unreachable("Not yet implemented!"); + return Result; +} + +bool XCOFFObjectFile::isSectionCompressed(DataRefImpl Sec) const { + bool Result = false; + llvm_unreachable("Not yet implemented!"); + return Result; +} + +bool XCOFFObjectFile::isSectionText(DataRefImpl Sec) const { + return getSectionFlags(Sec) & XCOFF::STYP_TEXT; +} + +bool XCOFFObjectFile::isSectionData(DataRefImpl Sec) const { + uint32_t Flags = getSectionFlags(Sec); + return Flags & (XCOFF::STYP_DATA | XCOFF::STYP_TDATA); +} + +bool XCOFFObjectFile::isSectionBSS(DataRefImpl Sec) const { + uint32_t Flags = getSectionFlags(Sec); + return Flags & (XCOFF::STYP_BSS | XCOFF::STYP_TBSS); +} + +bool XCOFFObjectFile::isSectionVirtual(DataRefImpl Sec) const { + return is64Bit() ? toSection64(Sec)->FileOffsetToRawData == 0 + : toSection32(Sec)->FileOffsetToRawData == 0; +} + +relocation_iterator XCOFFObjectFile::section_rel_begin(DataRefImpl Sec) const { + llvm_unreachable("Not yet implemented!"); + return relocation_iterator(RelocationRef()); +} + +relocation_iterator XCOFFObjectFile::section_rel_end(DataRefImpl Sec) const { + llvm_unreachable("Not yet implemented!"); + return relocation_iterator(RelocationRef()); +} + +void XCOFFObjectFile::moveRelocationNext(DataRefImpl &Rel) const { + llvm_unreachable("Not yet implemented!"); + return; +} + +uint64_t XCOFFObjectFile::getRelocationOffset(DataRefImpl Rel) const { + llvm_unreachable("Not yet implemented!"); + uint64_t Result = 0; + return Result; +} + +symbol_iterator XCOFFObjectFile::getRelocationSymbol(DataRefImpl Rel) const { + llvm_unreachable("Not yet implemented!"); + return symbol_iterator(SymbolRef()); +} + +uint64_t XCOFFObjectFile::getRelocationType(DataRefImpl Rel) const { + llvm_unreachable("Not yet implemented!"); + uint64_t Result = 0; + return Result; +} + +void XCOFFObjectFile::getRelocationTypeName( + DataRefImpl Rel, SmallVectorImpl<char> &Result) const { + llvm_unreachable("Not yet implemented!"); + return; +} + +uint32_t XCOFFObjectFile::getSymbolFlags(DataRefImpl Symb) const { + uint32_t Result = 0; + llvm_unreachable("Not yet implemented!"); + return Result; +} + +basic_symbol_iterator XCOFFObjectFile::symbol_begin() const { + assert(!is64Bit() && "64-bit support not implemented yet."); + DataRefImpl SymDRI; + SymDRI.p = reinterpret_cast<uintptr_t>(SymbolTblPtr); + return basic_symbol_iterator(SymbolRef(SymDRI, this)); +} + +basic_symbol_iterator XCOFFObjectFile::symbol_end() const { + assert(!is64Bit() && "64-bit support not implemented yet."); + DataRefImpl SymDRI; + SymDRI.p = reinterpret_cast<uintptr_t>( + SymbolTblPtr + getLogicalNumberOfSymbolTableEntries32()); + return basic_symbol_iterator(SymbolRef(SymDRI, this)); +} + +section_iterator XCOFFObjectFile::section_begin() const { + DataRefImpl DRI; + DRI.p = getSectionHeaderTableAddress(); + return section_iterator(SectionRef(DRI, this)); +} + +section_iterator XCOFFObjectFile::section_end() const { + DataRefImpl DRI; + DRI.p = getWithOffset(getSectionHeaderTableAddress(), + getNumberOfSections() * getSectionHeaderSize()); + return section_iterator(SectionRef(DRI, this)); +} + +uint8_t XCOFFObjectFile::getBytesInAddress() const { return is64Bit() ? 8 : 4; } + +StringRef XCOFFObjectFile::getFileFormatName() const { + return is64Bit() ? "aix5coff64-rs6000" : "aixcoff-rs6000"; +} + +Triple::ArchType XCOFFObjectFile::getArch() const { + return is64Bit() ? Triple::ppc64 : Triple::ppc; +} + +SubtargetFeatures XCOFFObjectFile::getFeatures() const { + return SubtargetFeatures(); +} + +bool XCOFFObjectFile::isRelocatableObject() const { + bool Result = false; + llvm_unreachable("Not yet implemented!"); + return Result; +} + +Expected<uint64_t> XCOFFObjectFile::getStartAddress() const { + // TODO FIXME Should get from auxiliary_header->o_entry when support for the + // auxiliary_header is added. + return 0; +} + +size_t XCOFFObjectFile::getFileHeaderSize() const { + return is64Bit() ? sizeof(XCOFFFileHeader64) : sizeof(XCOFFFileHeader32); +} + +size_t XCOFFObjectFile::getSectionHeaderSize() const { + return is64Bit() ? sizeof(XCOFFSectionHeader64) : + sizeof(XCOFFSectionHeader32); +} + +bool XCOFFObjectFile::is64Bit() const { + return Binary::ID_XCOFF64 == getType(); +} + +uint16_t XCOFFObjectFile::getMagic() const { + return is64Bit() ? fileHeader64()->Magic : fileHeader32()->Magic; +} + +Expected<DataRefImpl> XCOFFObjectFile::getSectionByNum(int16_t Num) const { + if (Num <= 0 || Num > getNumberOfSections()) + return errorCodeToError(object_error::invalid_section_index); + + DataRefImpl DRI; + DRI.p = getWithOffset(getSectionHeaderTableAddress(), + getSectionHeaderSize() * (Num - 1)); + return DRI; +} + +Expected<StringRef> +XCOFFObjectFile::getSymbolSectionName(const XCOFFSymbolEntry *SymEntPtr) const { + assert(!is64Bit() && "Symbol table support not implemented for 64-bit."); + int16_t SectionNum = SymEntPtr->SectionNumber; + + switch (SectionNum) { + case XCOFF::N_DEBUG: + return "N_DEBUG"; + case XCOFF::N_ABS: + return "N_ABS"; + case XCOFF::N_UNDEF: + return "N_UNDEF"; + default: + Expected<DataRefImpl> SecRef = getSectionByNum(SectionNum); + if (SecRef) + return generateXCOFFFixedNameStringRef( + getSectionNameInternal(SecRef.get())); + return SecRef.takeError(); + } +} + +bool XCOFFObjectFile::isReservedSectionNumber(int16_t SectionNumber) { + return (SectionNumber <= 0 && SectionNumber >= -2); +} + +uint16_t XCOFFObjectFile::getNumberOfSections() const { + return is64Bit() ? fileHeader64()->NumberOfSections + : fileHeader32()->NumberOfSections; +} + +int32_t XCOFFObjectFile::getTimeStamp() const { + return is64Bit() ? fileHeader64()->TimeStamp : fileHeader32()->TimeStamp; +} + +uint16_t XCOFFObjectFile::getOptionalHeaderSize() const { + return is64Bit() ? fileHeader64()->AuxHeaderSize + : fileHeader32()->AuxHeaderSize; +} + +uint32_t XCOFFObjectFile::getSymbolTableOffset32() const { + return fileHeader32()->SymbolTableOffset; +} + +int32_t XCOFFObjectFile::getRawNumberOfSymbolTableEntries32() const { + // As far as symbol table size is concerned, if this field is negative it is + // to be treated as a 0. However since this field is also used for printing we + // don't want to truncate any negative values. + return fileHeader32()->NumberOfSymTableEntries; +} + +uint32_t XCOFFObjectFile::getLogicalNumberOfSymbolTableEntries32() const { + return (fileHeader32()->NumberOfSymTableEntries >= 0 + ? fileHeader32()->NumberOfSymTableEntries + : 0); +} + +uint64_t XCOFFObjectFile::getSymbolTableOffset64() const { + return fileHeader64()->SymbolTableOffset; +} + +uint32_t XCOFFObjectFile::getNumberOfSymbolTableEntries64() const { + return fileHeader64()->NumberOfSymTableEntries; +} + +uintptr_t XCOFFObjectFile::getEndOfSymbolTableAddress() const { + uint32_t NumberOfSymTableEntries = + is64Bit() ? getNumberOfSymbolTableEntries64() + : getLogicalNumberOfSymbolTableEntries32(); + return getWithOffset(reinterpret_cast<uintptr_t>(SymbolTblPtr), + XCOFF::SymbolTableEntrySize * NumberOfSymTableEntries); +} + +void XCOFFObjectFile::checkSymbolEntryPointer(uintptr_t SymbolEntPtr) const { + if (SymbolEntPtr < reinterpret_cast<uintptr_t>(SymbolTblPtr)) + report_fatal_error("Symbol table entry is outside of symbol table."); + + if (SymbolEntPtr >= getEndOfSymbolTableAddress()) + report_fatal_error("Symbol table entry is outside of symbol table."); + + ptrdiff_t Offset = reinterpret_cast<const char *>(SymbolEntPtr) - + reinterpret_cast<const char *>(SymbolTblPtr); + + if (Offset % XCOFF::SymbolTableEntrySize != 0) + report_fatal_error( + "Symbol table entry position is not valid inside of symbol table."); +} + +uint32_t XCOFFObjectFile::getSymbolIndex(uintptr_t SymbolEntPtr) const { + return (reinterpret_cast<const char *>(SymbolEntPtr) - + reinterpret_cast<const char *>(SymbolTblPtr)) / + XCOFF::SymbolTableEntrySize; +} + +Expected<StringRef> +XCOFFObjectFile::getSymbolNameByIndex(uint32_t Index) const { + if (is64Bit()) + report_fatal_error("64-bit symbol table support not implemented yet."); + + if (Index >= getLogicalNumberOfSymbolTableEntries32()) + return errorCodeToError(object_error::invalid_symbol_index); + + DataRefImpl SymDRI; + SymDRI.p = reinterpret_cast<uintptr_t>(getPointerToSymbolTable() + Index); + return getSymbolName(SymDRI); +} + +uint16_t XCOFFObjectFile::getFlags() const { + return is64Bit() ? fileHeader64()->Flags : fileHeader32()->Flags; +} + +const char *XCOFFObjectFile::getSectionNameInternal(DataRefImpl Sec) const { + return is64Bit() ? toSection64(Sec)->Name : toSection32(Sec)->Name; +} + +uintptr_t XCOFFObjectFile::getSectionHeaderTableAddress() const { + return reinterpret_cast<uintptr_t>(SectionHeaderTable); +} + +int32_t XCOFFObjectFile::getSectionFlags(DataRefImpl Sec) const { + return is64Bit() ? toSection64(Sec)->Flags : toSection32(Sec)->Flags; +} + +XCOFFObjectFile::XCOFFObjectFile(unsigned int Type, MemoryBufferRef Object) + : ObjectFile(Type, Object) { + assert(Type == Binary::ID_XCOFF32 || Type == Binary::ID_XCOFF64); +} + +ArrayRef<XCOFFSectionHeader64> XCOFFObjectFile::sections64() const { + assert(is64Bit() && "64-bit interface called for non 64-bit file."); + const XCOFFSectionHeader64 *TablePtr = sectionHeaderTable64(); + return ArrayRef<XCOFFSectionHeader64>(TablePtr, + TablePtr + getNumberOfSections()); +} + +ArrayRef<XCOFFSectionHeader32> XCOFFObjectFile::sections32() const { + assert(!is64Bit() && "32-bit interface called for non 32-bit file."); + const XCOFFSectionHeader32 *TablePtr = sectionHeaderTable32(); + return ArrayRef<XCOFFSectionHeader32>(TablePtr, + TablePtr + getNumberOfSections()); +} + +// In an XCOFF32 file, when the field value is 65535, then an STYP_OVRFLO +// section header contains the actual count of relocation entries in the s_paddr +// field. STYP_OVRFLO headers contain the section index of their corresponding +// sections as their raw "NumberOfRelocations" field value. +Expected<uint32_t> XCOFFObjectFile::getLogicalNumberOfRelocationEntries( + const XCOFFSectionHeader32 &Sec) const { + + uint16_t SectionIndex = &Sec - sectionHeaderTable32() + 1; + + if (Sec.NumberOfRelocations < RELOC_OVERFLOW) + return Sec.NumberOfRelocations; + for (const auto &Sec : sections32()) { + if (Sec.Flags == XCOFF::STYP_OVRFLO && + Sec.NumberOfRelocations == SectionIndex) + return Sec.PhysicalAddress; + } + return errorCodeToError(object_error::parse_failed); +} + +Expected<ArrayRef<XCOFFRelocation32>> +XCOFFObjectFile::relocations(const XCOFFSectionHeader32 &Sec) const { + uintptr_t RelocAddr = getWithOffset(reinterpret_cast<uintptr_t>(FileHeader), + Sec.FileOffsetToRelocationInfo); + auto NumRelocEntriesOrErr = getLogicalNumberOfRelocationEntries(Sec); + if (Error E = NumRelocEntriesOrErr.takeError()) + return std::move(E); + + uint32_t NumRelocEntries = NumRelocEntriesOrErr.get(); + + auto RelocationOrErr = + getObject<XCOFFRelocation32>(Data, reinterpret_cast<void *>(RelocAddr), + NumRelocEntries * sizeof(XCOFFRelocation32)); + if (Error E = RelocationOrErr.takeError()) + return std::move(E); + + const XCOFFRelocation32 *StartReloc = RelocationOrErr.get(); + + return ArrayRef<XCOFFRelocation32>(StartReloc, StartReloc + NumRelocEntries); +} + +Expected<XCOFFStringTable> +XCOFFObjectFile::parseStringTable(const XCOFFObjectFile *Obj, uint64_t Offset) { + // If there is a string table, then the buffer must contain at least 4 bytes + // for the string table's size. Not having a string table is not an error. + if (auto EC = Binary::checkOffset( + Obj->Data, reinterpret_cast<uintptr_t>(Obj->base() + Offset), 4)) + return XCOFFStringTable{0, nullptr}; + + // Read the size out of the buffer. + uint32_t Size = support::endian::read32be(Obj->base() + Offset); + + // If the size is less then 4, then the string table is just a size and no + // string data. + if (Size <= 4) + return XCOFFStringTable{4, nullptr}; + + auto StringTableOrErr = + getObject<char>(Obj->Data, Obj->base() + Offset, Size); + if (Error E = StringTableOrErr.takeError()) + return std::move(E); + + const char *StringTablePtr = StringTableOrErr.get(); + if (StringTablePtr[Size - 1] != '\0') + return errorCodeToError(object_error::string_table_non_null_end); + + return XCOFFStringTable{Size, StringTablePtr}; +} + +Expected<std::unique_ptr<XCOFFObjectFile>> +XCOFFObjectFile::create(unsigned Type, MemoryBufferRef MBR) { + // Can't use std::make_unique because of the private constructor. + std::unique_ptr<XCOFFObjectFile> Obj; + Obj.reset(new XCOFFObjectFile(Type, MBR)); + + uint64_t CurOffset = 0; + const auto *Base = Obj->base(); + MemoryBufferRef Data = Obj->Data; + + // Parse file header. + auto FileHeaderOrErr = + getObject<void>(Data, Base + CurOffset, Obj->getFileHeaderSize()); + if (Error E = FileHeaderOrErr.takeError()) + return std::move(E); + Obj->FileHeader = FileHeaderOrErr.get(); + + CurOffset += Obj->getFileHeaderSize(); + // TODO FIXME we don't have support for an optional header yet, so just skip + // past it. + CurOffset += Obj->getOptionalHeaderSize(); + + // Parse the section header table if it is present. + if (Obj->getNumberOfSections()) { + auto SecHeadersOrErr = getObject<void>(Data, Base + CurOffset, + Obj->getNumberOfSections() * + Obj->getSectionHeaderSize()); + if (Error E = SecHeadersOrErr.takeError()) + return std::move(E); + Obj->SectionHeaderTable = SecHeadersOrErr.get(); + } + + // 64-bit object supports only file header and section headers for now. + if (Obj->is64Bit()) + return std::move(Obj); + + // If there is no symbol table we are done parsing the memory buffer. + if (Obj->getLogicalNumberOfSymbolTableEntries32() == 0) + return std::move(Obj); + + // Parse symbol table. + CurOffset = Obj->fileHeader32()->SymbolTableOffset; + uint64_t SymbolTableSize = (uint64_t)(sizeof(XCOFFSymbolEntry)) * + Obj->getLogicalNumberOfSymbolTableEntries32(); + auto SymTableOrErr = + getObject<XCOFFSymbolEntry>(Data, Base + CurOffset, SymbolTableSize); + if (Error E = SymTableOrErr.takeError()) + return std::move(E); + Obj->SymbolTblPtr = SymTableOrErr.get(); + CurOffset += SymbolTableSize; + + // Parse String table. + Expected<XCOFFStringTable> StringTableOrErr = + parseStringTable(Obj.get(), CurOffset); + if (Error E = StringTableOrErr.takeError()) + return std::move(E); + Obj->StringTable = StringTableOrErr.get(); + + return std::move(Obj); +} + +Expected<std::unique_ptr<ObjectFile>> +ObjectFile::createXCOFFObjectFile(MemoryBufferRef MemBufRef, + unsigned FileType) { + return XCOFFObjectFile::create(FileType, MemBufRef); +} + +XCOFF::StorageClass XCOFFSymbolRef::getStorageClass() const { + return OwningObjectPtr->toSymbolEntry(SymEntDataRef)->StorageClass; +} + +uint8_t XCOFFSymbolRef::getNumberOfAuxEntries() const { + return OwningObjectPtr->toSymbolEntry(SymEntDataRef)->NumberOfAuxEntries; +} + +const XCOFFCsectAuxEnt32 *XCOFFSymbolRef::getXCOFFCsectAuxEnt32() const { + assert(!OwningObjectPtr->is64Bit() && + "32-bit interface called on 64-bit object file."); + assert(hasCsectAuxEnt() && "No Csect Auxiliary Entry is found."); + + // In XCOFF32, the csect auxilliary entry is always the last auxiliary + // entry for the symbol. + uintptr_t AuxAddr = getWithOffset( + SymEntDataRef.p, XCOFF::SymbolTableEntrySize * getNumberOfAuxEntries()); + +#ifndef NDEBUG + OwningObjectPtr->checkSymbolEntryPointer(AuxAddr); +#endif + + return reinterpret_cast<const XCOFFCsectAuxEnt32 *>(AuxAddr); +} + +uint16_t XCOFFSymbolRef::getType() const { + return OwningObjectPtr->toSymbolEntry(SymEntDataRef)->SymbolType; +} + +int16_t XCOFFSymbolRef::getSectionNumber() const { + return OwningObjectPtr->toSymbolEntry(SymEntDataRef)->SectionNumber; +} + +bool XCOFFSymbolRef::hasCsectAuxEnt() const { + XCOFF::StorageClass SC = getStorageClass(); + return (SC == XCOFF::C_EXT || SC == XCOFF::C_WEAKEXT || + SC == XCOFF::C_HIDEXT); +} + +bool XCOFFSymbolRef::isFunction() const { + if (OwningObjectPtr->is64Bit()) + report_fatal_error("64-bit support is unimplemented yet."); + + if (getType() & FUNCTION_SYM) + return true; + + if (!hasCsectAuxEnt()) + return false; + + const XCOFFCsectAuxEnt32 *CsectAuxEnt = getXCOFFCsectAuxEnt32(); + + // A function definition should be a label definition. + if ((CsectAuxEnt->SymbolAlignmentAndType & SYM_TYPE_MASK) != XCOFF::XTY_LD) + return false; + + if (CsectAuxEnt->StorageMappingClass != XCOFF::XMC_PR) + return false; + + int16_t SectNum = getSectionNumber(); + Expected<DataRefImpl> SI = OwningObjectPtr->getSectionByNum(SectNum); + if (!SI) + return false; + + return (OwningObjectPtr->getSectionFlags(SI.get()) & XCOFF::STYP_TEXT); +} + +// Explictly instantiate template classes. +template struct XCOFFSectionHeader<XCOFFSectionHeader32>; +template struct XCOFFSectionHeader<XCOFFSectionHeader64>; + +} // namespace object +} // namespace llvm |