X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FMC%2FMachObjectWriter.cpp;h=5820a224c527b57f060d3212fc36512de3649079;hb=fef904d0e824a2c587f8c1063b6c4fbf47fec898;hp=69efe231ad6e97ceb0127fa3f942f06e116b0456;hpb=ba8297ec08cdf7ae0c1e0c18ce07922e1f822643;p=oota-llvm.git diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp index 69efe231ad6..5820a224c52 100644 --- a/lib/MC/MachObjectWriter.cpp +++ b/lib/MC/MachObjectWriter.cpp @@ -8,20 +8,21 @@ //===----------------------------------------------------------------------===// #include "llvm/MC/MCMachObjectWriter.h" -#include "llvm/ADT/OwningPtr.h" #include "llvm/ADT/StringMap.h" #include "llvm/ADT/Twine.h" #include "llvm/MC/MCAssembler.h" +#include "llvm/MC/MCAsmBackend.h" #include "llvm/MC/MCAsmLayout.h" #include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCFixupKindInfo.h" #include "llvm/MC/MCObjectWriter.h" #include "llvm/MC/MCSectionMachO.h" #include "llvm/MC/MCSymbol.h" #include "llvm/MC/MCMachOSymbolFlags.h" #include "llvm/MC/MCValue.h" #include "llvm/Object/MachOFormat.h" +#include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" -#include "llvm/Target/TargetAsmBackend.h" #include using namespace llvm; @@ -291,7 +292,7 @@ void MachObjectWriter::WriteNlist(MachSymbolData &MSD, const MCSymbol &Symbol = Data.getSymbol(); uint8_t Type = 0; uint16_t Flags = Data.getFlags(); - uint32_t Address = 0; + uint64_t Address = 0; // Set the N_TYPE bits. See . // @@ -351,6 +352,21 @@ void MachObjectWriter::WriteNlist(MachSymbolData &MSD, Write32(Address); } +void MachObjectWriter::WriteLinkeditLoadCommand(uint32_t Type, + uint32_t DataOffset, + uint32_t DataSize) { + uint64_t Start = OS.tell(); + (void) Start; + + Write32(Type); + Write32(macho::LinkeditLoadCommandSize); + Write32(DataOffset); + Write32(DataSize); + + assert(OS.tell() - Start == macho::LinkeditLoadCommandSize); +} + + void MachObjectWriter::RecordRelocation(const MCAssembler &Asm, const MCAsmLayout &Layout, const MCFragment *Fragment, @@ -584,20 +600,41 @@ IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, // requires the compiler to use .set to absolutize the differences between // symbols which the compiler knows to be assembly time constants, so we // don't need to worry about considering symbol differences fully resolved. + // + // If the file isn't using sub-sections-via-symbols, we can make the + // same assumptions about any symbol that we normally make about + // assembler locals. if (!Asm.getBackend().hasReliableSymbolDifference()) { - if (!SA.isTemporary() || !SA.isInSection() || &SecA != &SecB) + if (!SA.isInSection() || &SecA != &SecB || + (!SA.isTemporary() && + FB.getAtom() != Asm.getSymbolData(SA).getFragment()->getAtom() && + Asm.getSubsectionsViaSymbols())) return false; return true; } + // For Darwin x86_64, there is one special case when the reference IsPCRel. + // If the fragment with the reference does not have a base symbol but meets + // the simple way of dealing with this, in that it is a temporary symbol in + // the same atom then it is assumed to be fully resolved. This is needed so + // a relocation entry is not created and so the static linker does not + // mess up the reference later. + else if(!FB.getAtom() && + SA.isTemporary() && SA.isInSection() && &SecA == &SecB){ + return true; + } } else { if (!TargetObjectWriter->useAggressiveSymbolFolding()) return false; } - const MCFragment &FA = *Asm.getSymbolData(SA).getFragment(); + const MCFragment *FA = Asm.getSymbolData(SA).getFragment(); + + // Bail if the symbol has no fragment. + if (!FA) + return false; - A_Base = FA.getAtom(); + A_Base = FA->getAtom(); if (!A_Base) return false; @@ -613,7 +650,8 @@ IsSymbolRefDifferenceFullyResolvedImpl(const MCAssembler &Asm, return false; } -void MachObjectWriter::WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) { +void MachObjectWriter::WriteObject(MCAssembler &Asm, + const MCAsmLayout &Layout) { unsigned NumSections = Asm.size(); // The section data starts after the header, the segment load command (and @@ -632,6 +670,13 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) macho::DysymtabLoadCommandSize); } + // Add the data-in-code load command size, if used. + unsigned NumDataRegions = Asm.getDataRegions().size(); + if (NumDataRegions) { + ++NumLoadCommands; + LoadCommandsSize += macho::LinkeditLoadCommandSize; + } + // Compute the total size of the section data, as well as its file size and vm // size. uint64_t SectionDataStart = (is64Bit() ? macho::Header64Size : @@ -679,6 +724,15 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) RelocTableEnd += NumRelocs * macho::RelocationInfoSize; } + // Write the data-in-code load command, if used. + uint64_t DataInCodeTableEnd = RelocTableEnd + NumDataRegions * 8; + if (NumDataRegions) { + uint64_t DataRegionsOffset = RelocTableEnd; + uint64_t DataRegionsSize = NumDataRegions * 8; + WriteLinkeditLoadCommand(macho::LCT_DataInCode, DataRegionsOffset, + DataRegionsSize); + } + // Write the symbol table load command, if used. if (NumSymbols) { unsigned FirstLocalSymbol = 0; @@ -695,10 +749,10 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) // If used, the indirect symbols are written after the section data. if (NumIndirectSymbols) - IndirectSymbolOffset = RelocTableEnd; + IndirectSymbolOffset = DataInCodeTableEnd; // The symbol table is written after the indirect symbol data. - uint64_t SymbolTableOffset = RelocTableEnd + IndirectSymbolSize; + uint64_t SymbolTableOffset = DataInCodeTableEnd + IndirectSymbolSize; // The string table is written after symbol table. uint64_t StringTableOffset = @@ -716,7 +770,7 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) // Write the actual section data. for (MCAssembler::const_iterator it = Asm.begin(), ie = Asm.end(); it != ie; ++it) { - Asm.WriteSectionData(it, Layout); + Asm.writeSectionData(it, Layout); uint64_t Pad = getPaddingSize(it, Layout); for (unsigned int i = 0; i < Pad; ++i) @@ -738,6 +792,23 @@ void MachObjectWriter::WriteObject(MCAssembler &Asm, const MCAsmLayout &Layout) } } + // Write out the data-in-code region payload, if there is one. + for (MCAssembler::const_data_region_iterator + it = Asm.data_region_begin(), ie = Asm.data_region_end(); + it != ie; ++it) { + const DataRegionData *Data = &(*it); + uint64_t Start = getSymbolAddress(&Layout.getAssembler().getSymbolData(*Data->Start), Layout); + uint64_t End = getSymbolAddress(&Layout.getAssembler().getSymbolData(*Data->End), Layout); + DEBUG(dbgs() << "data in code region-- kind: " << Data->Kind + << " start: " << Start << "(" << Data->Start->getName() << ")" + << " end: " << End << "(" << Data->End->getName() << ")" + << " size: " << End - Start + << "\n"); + Write32(Start); + Write16(End - Start); + Write16(Data->Kind); + } + // Write the symbol table data, if used. if (NumSymbols) { // Write the indirect symbol entries.