From 4c423773d85dd2655ab578b807eacfa0b33fdf3c Mon Sep 17 00:00:00 2001 From: Chris Bieneman Date: Fri, 3 Jun 2016 16:58:05 +0000 Subject: [yaml2obj] Sort MachO LinkEdit write operations based on offset This re-applies r271611, and hopefully the bots won't break this time. Although ld64 always outputs linkedit data in the same order, it isn't actually required to. This change makes yaml2obj resilient if the offsets are in arbitrary order. llvm-svn: 271687 --- llvm/tools/yaml2obj/yaml2macho.cpp | 90 +++++++++++++++++++++++++++----------- 1 file changed, 64 insertions(+), 26 deletions(-) (limited to 'llvm/tools/yaml2obj/yaml2macho.cpp') diff --git a/llvm/tools/yaml2obj/yaml2macho.cpp b/llvm/tools/yaml2obj/yaml2macho.cpp index d65aabc5c86..e08a3f2b9f9 100644 --- a/llvm/tools/yaml2obj/yaml2macho.cpp +++ b/llvm/tools/yaml2obj/yaml2macho.cpp @@ -46,8 +46,15 @@ private: Error writeLoadCommands(raw_ostream &OS); Error writeSectionData(raw_ostream &OS); Error writeLinkEditData(raw_ostream &OS); - void writeBindOpcodes(raw_ostream &OS, uint64_t offset, + void writeBindOpcodes(raw_ostream &OS, std::vector &BindOpcodes); + // LinkEdit writers + Error writeRebaseOpcodes(raw_ostream &OS); + Error writeBasicBindOpcodes(raw_ostream &OS); + Error writeWeakBindOpcodes(raw_ostream &OS); + Error writeLazyBindOpcodes(raw_ostream &OS); + Error writeNameList(raw_ostream &OS); + Error writeStringTable(raw_ostream &OS); Error writeExportTrie(raw_ostream &OS); void dumpExportEntry(raw_ostream &OS, MachOYAML::ExportEntry &Entry); @@ -275,9 +282,7 @@ Error MachOWriter::writeSectionData(raw_ostream &OS) { } void MachOWriter::writeBindOpcodes( - raw_ostream &OS, uint64_t offset, - std::vector &BindOpcodes) { - ZeroToOffset(OS, offset); + raw_ostream &OS, std::vector &BindOpcodes) { for (auto Opcode : BindOpcodes) { uint8_t OpByte = Opcode.Opcode | Opcode.Imm; @@ -337,21 +342,53 @@ void writeNListEntry(MachOYAML::NListEntry &NLE, raw_ostream &OS) { } Error MachOWriter::writeLinkEditData(raw_ostream &OS) { - MachOYAML::LinkEditData &LinkEdit = Obj.LinkEdit; + typedef Error (MachOWriter::*writeHandler)(raw_ostream &); + typedef std::pair writeOperation; + std::vector WriteQueue; + MachO::dyld_info_command *DyldInfoOnlyCmd = 0; MachO::symtab_command *SymtabCmd = 0; for (auto &LC : Obj.LoadCommands) { switch (LC.Data.load_command_data.cmd) { case MachO::LC_SYMTAB: SymtabCmd = &LC.Data.symtab_command_data; + WriteQueue.push_back( + std::make_pair(SymtabCmd->symoff, &MachOWriter::writeNameList)); + WriteQueue.push_back( + std::make_pair(SymtabCmd->stroff, &MachOWriter::writeStringTable)); break; case MachO::LC_DYLD_INFO_ONLY: DyldInfoOnlyCmd = &LC.Data.dyld_info_command_data; + WriteQueue.push_back(std::make_pair(DyldInfoOnlyCmd->rebase_off, + &MachOWriter::writeRebaseOpcodes)); + WriteQueue.push_back(std::make_pair(DyldInfoOnlyCmd->bind_off, + &MachOWriter::writeBasicBindOpcodes)); + WriteQueue.push_back(std::make_pair(DyldInfoOnlyCmd->weak_bind_off, + &MachOWriter::writeWeakBindOpcodes)); + WriteQueue.push_back(std::make_pair(DyldInfoOnlyCmd->lazy_bind_off, + &MachOWriter::writeLazyBindOpcodes)); + WriteQueue.push_back(std::make_pair(DyldInfoOnlyCmd->export_off, + &MachOWriter::writeExportTrie)); break; } } - ZeroToOffset(OS, DyldInfoOnlyCmd->rebase_off); + std::sort(WriteQueue.begin(), WriteQueue.end(), + [](const writeOperation &a, const writeOperation &b) { + return a.first < b.first; + }); + + for (auto writeOp : WriteQueue) { + ZeroToOffset(OS, writeOp.first); + if (auto Err = (this->*writeOp.second)(OS)) + return Err; + } + + return Error::success(); +} + +Error MachOWriter::writeRebaseOpcodes(raw_ostream &OS) { + MachOYAML::LinkEditData &LinkEdit = Obj.LinkEdit; for (auto Opcode : LinkEdit.RebaseOpcodes) { uint8_t OpByte = Opcode.Opcode | Opcode.Imm; @@ -360,38 +397,39 @@ Error MachOWriter::writeLinkEditData(raw_ostream &OS) { encodeULEB128(Data, OS); } } + return Error::success(); +} - writeBindOpcodes(OS, DyldInfoOnlyCmd->bind_off, LinkEdit.BindOpcodes); - writeBindOpcodes(OS, DyldInfoOnlyCmd->weak_bind_off, - LinkEdit.WeakBindOpcodes); - writeBindOpcodes(OS, DyldInfoOnlyCmd->lazy_bind_off, - LinkEdit.LazyBindOpcodes); +Error MachOWriter::writeBasicBindOpcodes(raw_ostream &OS) { + writeBindOpcodes(OS, Obj.LinkEdit.BindOpcodes); + return Error::success(); +} - ZeroToOffset(OS, DyldInfoOnlyCmd->export_off); - if (auto Err = writeExportTrie(OS)) - return Err; +Error MachOWriter::writeWeakBindOpcodes(raw_ostream &OS) { + writeBindOpcodes(OS, Obj.LinkEdit.WeakBindOpcodes); + return Error::success(); +} + +Error MachOWriter::writeLazyBindOpcodes(raw_ostream &OS) { + writeBindOpcodes(OS, Obj.LinkEdit.LazyBindOpcodes); + return Error::success(); +} - ZeroToOffset(OS, SymtabCmd->symoff); - - for (auto NLE : LinkEdit.NameList) { +Error MachOWriter::writeNameList(raw_ostream &OS) { + for (auto NLE : Obj.LinkEdit.NameList) { if (is64Bit) writeNListEntry(NLE, OS); else writeNListEntry(NLE, OS); } + return Error::success(); +} - auto currOffset = OS.tell() - fileStart; - if (currOffset < SymtabCmd->stroff) - Fill(OS, SymtabCmd->stroff - currOffset, 0xDEADBEEFu); - - for (auto Str : LinkEdit.StringTable) { +Error MachOWriter::writeStringTable(raw_ostream &OS) { + for (auto Str : Obj.LinkEdit.StringTable) { OS.write(Str.data(), Str.size()); OS.write('\0'); } - - // Fill to the end of the string table - ZeroToOffset(OS, SymtabCmd->stroff + SymtabCmd->strsize); - return Error::success(); } -- cgit v1.2.3