X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FMachOWriter.cpp;h=0c743759da6c0aef0a4e80fc01edba2e1f9c514e;hb=5c0d6ed325417baa5d119af9c2b6790231d8565f;hp=5ffd978f340cf28ad94999cf05ae4741e00ccb80;hpb=94be248dbb2d2a44e8f4d47f161b93704d33d279;p=oota-llvm.git diff --git a/lib/CodeGen/MachOWriter.cpp b/lib/CodeGen/MachOWriter.cpp index 5ffd978f340..0c743759da6 100644 --- a/lib/CodeGen/MachOWriter.cpp +++ b/lib/CodeGen/MachOWriter.cpp @@ -22,18 +22,34 @@ // //===----------------------------------------------------------------------===// +#include "MachOWriter.h" +#include "llvm/Constants.h" +#include "llvm/DerivedTypes.h" #include "llvm/Module.h" +#include "llvm/PassManager.h" +#include "llvm/CodeGen/FileWriters.h" #include "llvm/CodeGen/MachineCodeEmitter.h" #include "llvm/CodeGen/MachineConstantPool.h" -#include "llvm/CodeGen/MachOWriter.h" -#include "llvm/ExecutionEngine/ExecutionEngine.h" +#include "llvm/CodeGen/MachineJumpTableInfo.h" +#include "llvm/Target/TargetAsmInfo.h" #include "llvm/Target/TargetJITInfo.h" #include "llvm/Support/Mangler.h" #include "llvm/Support/MathExtras.h" +#include "llvm/Support/OutputBuffer.h" +#include "llvm/Support/Streams.h" #include -#include using namespace llvm; +/// AddMachOWriter - Concrete function to add the Mach-O writer to the function +/// pass manager. +MachineCodeEmitter *llvm::AddMachOWriter(FunctionPassManager &FPM, + std::ostream &O, + TargetMachine &TM) { + MachOWriter *MOW = new MachOWriter(O, TM); + FPM.add(MOW); + return &MOW->getMachineCodeEmitter(); +} + //===----------------------------------------------------------------------===// // MachOCodeEmitter Implementation //===----------------------------------------------------------------------===// @@ -43,13 +59,29 @@ namespace llvm { /// for functions to the Mach-O file. class MachOCodeEmitter : public MachineCodeEmitter { MachOWriter &MOW; - - /// MOS - The current section we're writing to - MachOWriter::MachOSection *MOS; + + /// Target machine description. + TargetMachine &TM; + + /// is64Bit/isLittleEndian - This information is inferred from the target + /// machine directly, indicating what header values and flags to set. + bool is64Bit, isLittleEndian; /// Relocations - These are the relocations that the function needs, as /// emitted. std::vector Relocations; + + /// CPLocations - This is a map of constant pool indices to offsets from the + /// start of the section for that constant pool index. + std::vector CPLocations; + + /// CPSections - This is a map of constant pool indices to the MachOSection + /// containing the constant pool entry for that index. + std::vector CPSections; + + /// JTLocations - This is a map of jump table indices to offsets from the + /// start of the section for that jump table index. + std::vector JTLocations; /// MBBLocations - This vector is a mapping from MBB ID's to their address. /// It is filled in by the StartMachineBasicBlock callback and queried by @@ -57,28 +89,34 @@ namespace llvm { std::vector MBBLocations; public: - MachOCodeEmitter(MachOWriter &mow) : MOW(mow) {} + MachOCodeEmitter(MachOWriter &mow) : MOW(mow), TM(MOW.TM) { + is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64; + isLittleEndian = TM.getTargetData()->isLittleEndian(); + } - void startFunction(MachineFunction &F); - bool finishFunction(MachineFunction &F); + virtual void startFunction(MachineFunction &MF); + virtual bool finishFunction(MachineFunction &MF); - void addRelocation(const MachineRelocation &MR) { + virtual void addRelocation(const MachineRelocation &MR) { Relocations.push_back(MR); } - virtual void StartMachineBasicBlock(MachineBasicBlock *MBB) { - if (MBBLocations.size() <= (unsigned)MBB->getNumber()) - MBBLocations.resize((MBB->getNumber()+1)*2); - MBBLocations[MBB->getNumber()] = getCurrentPCValue(); - } - + void emitConstantPool(MachineConstantPool *MCP); + void emitJumpTables(MachineJumpTableInfo *MJTI); + virtual intptr_t getConstantPoolEntryAddress(unsigned Index) const { - assert(0 && "CP not implementated yet!"); - return 0; + assert(CPLocations.size() > Index && "CP not emitted!"); + return CPLocations[Index]; } virtual intptr_t getJumpTableEntryAddress(unsigned Index) const { - assert(0 && "JT not implementated yet!"); - return 0; + assert(JTLocations.size() > Index && "JT not emitted!"); + return JTLocations[Index]; + } + + virtual void StartMachineBasicBlock(MachineBasicBlock *MBB) { + if (MBBLocations.size() <= (unsigned)MBB->getNumber()) + MBBLocations.resize((MBB->getNumber()+1)*2); + MBBLocations[MBB->getNumber()] = getCurrentPCOffset(); } virtual intptr_t getMachineBasicBlockAddress(MachineBasicBlock *MBB) const { @@ -88,11 +126,11 @@ namespace llvm { } /// JIT SPECIFIC FUNCTIONS - DO NOT IMPLEMENT THESE HERE! - void startFunctionStub(unsigned StubSize) { + virtual void startFunctionStub(unsigned StubSize, unsigned Alignment = 1) { assert(0 && "JIT specific function called!"); abort(); } - void *finishFunctionStub(const Function *F) { + virtual void *finishFunctionStub(const Function *F) { assert(0 && "JIT specific function called!"); abort(); return 0; @@ -102,56 +140,97 @@ namespace llvm { /// startFunction - This callback is invoked when a new machine function is /// about to be emitted. -void MachOCodeEmitter::startFunction(MachineFunction &F) { +void MachOCodeEmitter::startFunction(MachineFunction &MF) { + const TargetData *TD = TM.getTargetData(); + const Function *F = MF.getFunction(); + // Align the output buffer to the appropriate alignment, power of 2. - // FIXME: GENERICIZE!! - unsigned Align = 4; + unsigned FnAlign = F->getAlignment(); + unsigned TDAlign = TD->getPrefTypeAlignment(F->getType()); + unsigned Align = Log2_32(std::max(FnAlign, TDAlign)); + assert(!(Align & (Align-1)) && "Alignment is not a power of two!"); // Get the Mach-O Section that this function belongs in. - MOS = &MOW.getTextSection(); + MachOWriter::MachOSection *MOS = MOW.getTextSection(); - // FIXME: better memory management + // FIXME: better memory management MOS->SectionData.reserve(4096); - BufferBegin = &(MOS->SectionData[0]); + BufferBegin = &MOS->SectionData[0]; BufferEnd = BufferBegin + MOS->SectionData.capacity(); - CurBufferPtr = BufferBegin + MOS->size; // Upgrade the section alignment if required. if (MOS->align < Align) MOS->align = Align; - // Make sure we only relocate to this function's MBBs. + // Round the size up to the correct alignment for starting the new function. + if ((MOS->size & ((1 << Align) - 1)) != 0) { + MOS->size += (1 << Align); + MOS->size &= ~((1 << Align) - 1); + } + + // FIXME: Using MOS->size directly here instead of calculating it from the + // output buffer size (impossible because the code emitter deals only in raw + // bytes) forces us to manually synchronize size and write padding zero bytes + // to the output buffer for all non-text sections. For text sections, we do + // not synchonize the output buffer, and we just blow up if anyone tries to + // write non-code to it. An assert should probably be added to + // AddSymbolToSection to prevent calling it on the text section. + CurBufferPtr = BufferBegin + MOS->size; + + // Clear per-function data structures. + CPLocations.clear(); + CPSections.clear(); + JTLocations.clear(); MBBLocations.clear(); } /// finishFunction - This callback is invoked after the function is completely /// finished. -bool MachOCodeEmitter::finishFunction(MachineFunction &F) { - MOS->size += CurBufferPtr - BufferBegin; - +bool MachOCodeEmitter::finishFunction(MachineFunction &MF) { + // Get the Mach-O Section that this function belongs in. + MachOWriter::MachOSection *MOS = MOW.getTextSection(); + // Get a symbol for the function to add to the symbol table - const GlobalValue *FuncV = F.getFunction(); - MachOSym FnSym(FuncV, MOW.Mang->getValueName(FuncV), MOS->Index); + // FIXME: it seems like we should call something like AddSymbolToSection + // in startFunction rather than changing the section size and symbol n_value + // here. + const GlobalValue *FuncV = MF.getFunction(); + MachOSym FnSym(FuncV, MOW.Mang->getValueName(FuncV), MOS->Index, TM); + FnSym.n_value = MOS->size; + MOS->size = CurBufferPtr - BufferBegin; + + // Emit constant pool to appropriate section(s) + emitConstantPool(MF.getConstantPool()); - // FIXME: emit constant pool to appropriate section(s) - // FIXME: emit jump table to appropriate section + // Emit jump tables to appropriate section + emitJumpTables(MF.getJumpTableInfo()); - // Resolve the function's relocations either to concrete pointers in the case - // of branches from one block to another, or to target relocation entries. + // If we have emitted any relocations to function-specific objects such as + // basic blocks, constant pools entries, or jump tables, record their + // addresses now so that we can rewrite them with the correct addresses + // later. for (unsigned i = 0, e = Relocations.size(); i != e; ++i) { MachineRelocation &MR = Relocations[i]; + intptr_t Addr; + if (MR.isBasicBlock()) { - void *MBBAddr = (void *)getMachineBasicBlockAddress(MR.getBasicBlock()); - MR.setResultPointer(MBBAddr); - MOW.TM.getJITInfo()->relocate(BufferBegin, &MR, 1, 0); - } else if (MR.isConstantPoolIndex() || MR.isJumpTableIndex()) { - // Get the address of the index. - uint64_t Addr = 0; - // Generate the relocation(s) for the index. - MOW.GetTargetRelocation(*MOS, MR, Addr); + Addr = getMachineBasicBlockAddress(MR.getBasicBlock()); + MR.setConstantVal(MOS->Index); + MR.setResultPointer((void*)Addr); + } else if (MR.isJumpTableIndex()) { + Addr = getJumpTableEntryAddress(MR.getJumpTableIndex()); + MR.setConstantVal(MOW.getJumpTableSection()->Index); + MR.setResultPointer((void*)Addr); + } else if (MR.isConstantPoolIndex()) { + Addr = getConstantPoolEntryAddress(MR.getConstantPoolIndex()); + MR.setConstantVal(CPSections[MR.getConstantPoolIndex()]); + MR.setResultPointer((void*)Addr); + } else if (MR.isGlobalValue()) { + // FIXME: This should be a set or something that uniques + MOW.PendingGlobals.push_back(MR.getGlobalValue()); } else { - // Handle other types later once we've finalized the sections in the file. - MOS->Relocations.push_back(MR); + assert(0 && "Unhandled relocation type"); } + MOS->Relocations.push_back(MR); } Relocations.clear(); @@ -160,11 +239,87 @@ bool MachOCodeEmitter::finishFunction(MachineFunction &F) { return false; } +/// emitConstantPool - For each constant pool entry, figure out which section +/// the constant should live in, allocate space for it, and emit it to the +/// Section data buffer. +void MachOCodeEmitter::emitConstantPool(MachineConstantPool *MCP) { + const std::vector &CP = MCP->getConstants(); + if (CP.empty()) return; + + // FIXME: handle PIC codegen + bool isPIC = TM.getRelocationModel() == Reloc::PIC_; + assert(!isPIC && "PIC codegen not yet handled for mach-o jump tables!"); + + // Although there is no strict necessity that I am aware of, we will do what + // gcc for OS X does and put each constant pool entry in a section of constant + // objects of a certain size. That means that float constants go in the + // literal4 section, and double objects go in literal8, etc. + // + // FIXME: revisit this decision if we ever do the "stick everything into one + // "giant object for PIC" optimization. + for (unsigned i = 0, e = CP.size(); i != e; ++i) { + const Type *Ty = CP[i].getType(); + unsigned Size = TM.getTargetData()->getTypeSize(Ty); + + MachOWriter::MachOSection *Sec = MOW.getConstSection(CP[i].Val.ConstVal); + OutputBuffer SecDataOut(Sec->SectionData, is64Bit, isLittleEndian); + + CPLocations.push_back(Sec->SectionData.size()); + CPSections.push_back(Sec->Index); + + // FIXME: remove when we have unified size + output buffer + Sec->size += Size; + + // Allocate space in the section for the global. + // FIXME: need alignment? + // FIXME: share between here and AddSymbolToSection? + for (unsigned j = 0; j < Size; ++j) + SecDataOut.outbyte(0); + + MOW.InitMem(CP[i].Val.ConstVal, &Sec->SectionData[0], CPLocations[i], + TM.getTargetData(), Sec->Relocations); + } +} + +/// emitJumpTables - Emit all the jump tables for a given jump table info +/// record to the appropriate section. +void MachOCodeEmitter::emitJumpTables(MachineJumpTableInfo *MJTI) { + const std::vector &JT = MJTI->getJumpTables(); + if (JT.empty()) return; + + // FIXME: handle PIC codegen + bool isPIC = TM.getRelocationModel() == Reloc::PIC_; + assert(!isPIC && "PIC codegen not yet handled for mach-o jump tables!"); + + MachOWriter::MachOSection *Sec = MOW.getJumpTableSection(); + unsigned TextSecIndex = MOW.getTextSection()->Index; + OutputBuffer SecDataOut(Sec->SectionData, is64Bit, isLittleEndian); + + for (unsigned i = 0, e = JT.size(); i != e; ++i) { + // For each jump table, record its offset from the start of the section, + // reserve space for the relocations to the MBBs, and add the relocations. + const std::vector &MBBs = JT[i].MBBs; + JTLocations.push_back(Sec->SectionData.size()); + for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi) { + MachineRelocation MR(MOW.GetJTRelocation(Sec->SectionData.size(), + MBBs[mi])); + MR.setResultPointer((void *)JTLocations[i]); + MR.setConstantVal(TextSecIndex); + Sec->Relocations.push_back(MR); + SecDataOut.outaddr(0); + } + } + // FIXME: remove when we have unified size + output buffer + Sec->size = Sec->SectionData.size(); +} + //===----------------------------------------------------------------------===// // MachOWriter Implementation //===----------------------------------------------------------------------===// -MachOWriter::MachOWriter(std::ostream &o, TargetMachine &tm) : O(o), TM(tm) { +char MachOWriter::ID = 0; +MachOWriter::MachOWriter(std::ostream &o, TargetMachine &tm) + : MachineFunctionPass((intptr_t)&ID), O(o), TM(tm) { is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64; isLittleEndian = TM.getTargetData()->isLittleEndian(); @@ -176,33 +331,51 @@ MachOWriter::~MachOWriter() { delete MCE; } -void MachOWriter::AddSymbolToSection(MachOSection &Sec, GlobalVariable *GV) { +void MachOWriter::AddSymbolToSection(MachOSection *Sec, GlobalVariable *GV) { const Type *Ty = GV->getType()->getElementType(); unsigned Size = TM.getTargetData()->getTypeSize(Ty); - unsigned Align = Log2_32(TM.getTargetData()->getTypeAlignment(Ty)); + unsigned Align = GV->getAlignment(); + if (Align == 0) + Align = TM.getTargetData()->getPrefTypeAlignment(Ty); - MachOSym Sym(GV, Mang->getValueName(GV), Sec.Index); // Reserve space in the .bss section for this symbol while maintaining the // desired section alignment, which must be at least as much as required by // this symbol. + OutputBuffer SecDataOut(Sec->SectionData, is64Bit, isLittleEndian); + if (Align) { - Sec.align = std::max(unsigned(Sec.align), Align); - Sec.size = (Sec.size + Align - 1) & ~(Align-1); + uint64_t OrigSize = Sec->size; + Align = Log2_32(Align); + Sec->align = std::max(unsigned(Sec->align), Align); + Sec->size = (Sec->size + Align - 1) & ~(Align-1); + + // Add alignment padding to buffer as well. + // FIXME: remove when we have unified size + output buffer + unsigned AlignedSize = Sec->size - OrigSize; + for (unsigned i = 0; i < AlignedSize; ++i) + SecDataOut.outbyte(0); } - // Record the offset of the symbol, and then allocate space for it. - Sym.n_value = Sec.size; - Sec.size += Size; - - switch (GV->getLinkage()) { - default: // weak/linkonce handled above - assert(0 && "Unexpected linkage type!"); - case GlobalValue::ExternalLinkage: - Sym.n_type |= MachOSym::N_EXT; - break; - case GlobalValue::InternalLinkage: - break; + // Globals without external linkage apparently do not go in the symbol table. + if (GV->getLinkage() != GlobalValue::InternalLinkage) { + MachOSym Sym(GV, Mang->getValueName(GV), Sec->Index, TM); + Sym.n_value = Sec->size; + SymbolTable.push_back(Sym); } - SymbolTable.push_back(Sym); + + // Record the offset of the symbol, and then allocate space for it. + // FIXME: remove when we have unified size + output buffer + Sec->size += Size; + + // Now that we know what section the GlovalVariable is going to be emitted + // into, update our mappings. + // FIXME: We may also need to update this when outputting non-GlobalVariable + // GlobalValues such as functions. + GVSection[GV] = Sec; + GVOffset[GV] = Sec->SectionData.size(); + + // Allocate space in the section for the global. + for (unsigned i = 0; i < Size; ++i) + SecDataOut.outbyte(0); } void MachOWriter::EmitGlobal(GlobalVariable *GV) { @@ -217,20 +390,17 @@ void MachOWriter::EmitGlobal(GlobalVariable *GV) { // part of the common block if they are zero initialized and allowed to be // merged with other symbols. if (NoInit || GV->hasLinkOnceLinkage() || GV->hasWeakLinkage()) { - MachOSym ExtOrCommonSym(GV, Mang->getValueName(GV), MachOSym::NO_SECT); + MachOSym ExtOrCommonSym(GV, Mang->getValueName(GV), MachOSym::NO_SECT,TM); // For undefined (N_UNDF) external (N_EXT) types, n_value is the size in // bytes of the symbol. ExtOrCommonSym.n_value = Size; - // If the symbol is external, we'll put it on a list of symbols whose - // addition to the symbol table is being pended until we find a reference - if (NoInit) - PendingSyms.push_back(ExtOrCommonSym); - else - SymbolTable.push_back(ExtOrCommonSym); + SymbolTable.push_back(ExtOrCommonSym); + // Remember that we've seen this symbol + GVOffset[GV] = Size; return; } // Otherwise, this symbol is part of the .bss section. - MachOSection &BSS = getBSSSection(); + MachOSection *BSS = getBSSSection(); AddSymbolToSection(BSS, GV); return; } @@ -238,23 +408,11 @@ void MachOWriter::EmitGlobal(GlobalVariable *GV) { // Scalar read-only data goes in a literal section if the scalar is 4, 8, or // 16 bytes, or a cstring. Other read only data goes into a regular const // section. Read-write data goes in the data section. - MachOSection &Sec = GV->isConstant() ? getConstSection(Ty) : getDataSection(); + MachOSection *Sec = GV->isConstant() ? getConstSection(GV->getInitializer()) : + getDataSection(); AddSymbolToSection(Sec, GV); - - // FIXME: A couple significant changes are required for this to work, even for - // trivial cases such as a constant integer: - // 0. InitializeMemory needs to be split out of ExecutionEngine. We don't - // want to have to create an ExecutionEngine such as JIT just to write - // some bytes into a buffer. The only thing necessary for - // InitializeMemory to function properly should be TargetData. - // - // 1. InitializeMemory needs to be enhanced to return MachineRelocations - // rather than accessing the address of objects such basic blocks, - // constant pools, and jump tables. The client of InitializeMemory such - // as an object writer or jit emitter should then handle these relocs - // appropriately. - // - // FIXME: need to allocate memory for the global initializer. + InitMem(GV->getInitializer(), &Sec->SectionData[0], GVOffset[GV], + TM.getTargetData(), Sec->Relocations); } @@ -287,19 +445,12 @@ bool MachOWriter::doFinalization(Module &M) { I != E; ++I) EmitGlobal(I); - // Emit the symbol table to temporary buffers, so that we know the size of - // the string table when we write the load commands in the next phase. - BufferSymbolAndStringTable(); - // Emit the header and load commands. EmitHeaderAndLoadCommands(); - // Emit the text and data sections. + // Emit the various sections and their relocation info. EmitSections(); - // Emit the relocation entry data for each section. - O.write((char*)&RelocBuffer[0], RelocBuffer.size()); - // Write the symbol table and the string table to the end of the file. O.write((char*)&SymT[0], SymT.size()); O.write((char*)&StrT[0], StrT.size()); @@ -320,7 +471,7 @@ void MachOWriter::EmitHeaderAndLoadCommands() { MachOSegment SEG("", is64Bit); SEG.nsects = SectionList.size(); SEG.cmdsize = SEG.cmdSize(is64Bit) + - SEG.nsects * SectionList.begin()->cmdSize(is64Bit); + SEG.nsects * SectionList[0]->cmdSize(is64Bit); // Step #1: calculate the number of load commands. We always have at least // one, for the LC_SEGMENT load command, plus two for the normal @@ -335,112 +486,119 @@ void MachOWriter::EmitHeaderAndLoadCommands() { // Step #3: write the header to the file // Local alias to shortenify coming code. DataBuffer &FH = Header.HeaderData; - outword(FH, Header.magic); - outword(FH, Header.cputype); - outword(FH, Header.cpusubtype); - outword(FH, Header.filetype); - outword(FH, Header.ncmds); - outword(FH, Header.sizeofcmds); - outword(FH, Header.flags); + OutputBuffer FHOut(FH, is64Bit, isLittleEndian); + + FHOut.outword(Header.magic); + FHOut.outword(TM.getMachOWriterInfo()->getCPUType()); + FHOut.outword(TM.getMachOWriterInfo()->getCPUSubType()); + FHOut.outword(Header.filetype); + FHOut.outword(Header.ncmds); + FHOut.outword(Header.sizeofcmds); + FHOut.outword(Header.flags); if (is64Bit) - outword(FH, Header.reserved); + FHOut.outword(Header.reserved); // Step #4: Finish filling in the segment load command and write it out - for (std::list::iterator I = SectionList.begin(), + for (std::vector::iterator I = SectionList.begin(), E = SectionList.end(); I != E; ++I) - SEG.filesize += I->size; + SEG.filesize += (*I)->size; + SEG.vmsize = SEG.filesize; SEG.fileoff = Header.cmdSize(is64Bit) + Header.sizeofcmds; - outword(FH, SEG.cmd); - outword(FH, SEG.cmdsize); - outstring(FH, SEG.segname, 16); - outaddr(FH, SEG.vmaddr); - outaddr(FH, SEG.vmsize); - outaddr(FH, SEG.fileoff); - outaddr(FH, SEG.filesize); - outword(FH, SEG.maxprot); - outword(FH, SEG.initprot); - outword(FH, SEG.nsects); - outword(FH, SEG.flags); + FHOut.outword(SEG.cmd); + FHOut.outword(SEG.cmdsize); + FHOut.outstring(SEG.segname, 16); + FHOut.outaddr(SEG.vmaddr); + FHOut.outaddr(SEG.vmsize); + FHOut.outaddr(SEG.fileoff); + FHOut.outaddr(SEG.filesize); + FHOut.outword(SEG.maxprot); + FHOut.outword(SEG.initprot); + FHOut.outword(SEG.nsects); + FHOut.outword(SEG.flags); // Step #5: Finish filling in the fields of the MachOSections uint64_t currentAddr = 0; - for (std::list::iterator I = SectionList.begin(), + for (std::vector::iterator I = SectionList.begin(), E = SectionList.end(); I != E; ++I) { - I->addr = currentAddr; - I->offset = currentAddr + SEG.fileoff; + MachOSection *MOS = *I; + MOS->addr = currentAddr; + MOS->offset = currentAddr + SEG.fileoff; + // FIXME: do we need to do something with alignment here? - currentAddr += I->size; + currentAddr += MOS->size; } - // Step #6: Calculate the number of relocations for each section and write out + // Step #6: Emit the symbol table to temporary buffers, so that we know the + // size of the string table when we write the next load command. This also + // sorts and assigns indices to each of the symbols, which is necessary for + // emitting relocations to externally-defined objects. + BufferSymbolAndStringTable(); + + // Step #7: Calculate the number of relocations for each section and write out // the section commands for each section currentAddr += SEG.fileoff; - for (std::list::iterator I = SectionList.begin(), + for (std::vector::iterator I = SectionList.begin(), E = SectionList.end(); I != E; ++I) { - // calculate the relocation info for this section command - // FIXME: this could get complicated calculating the address argument, we - // should probably split this out into its own function. - for (unsigned i = 0, e = I->Relocations.size(); i != e; ++i) - GetTargetRelocation(*I, I->Relocations[i], 0); - if (I->nreloc != 0) { - I->reloff = currentAddr; - currentAddr += I->nreloc * 8; - } + MachOSection *MOS = *I; + // Convert the relocations to target-specific relocations, and fill in the + // relocation offset for this section. + CalculateRelocations(*MOS); + MOS->reloff = MOS->nreloc ? currentAddr : 0; + currentAddr += MOS->nreloc * 8; // write the finalized section command to the output buffer - outstring(FH, I->sectname, 16); - outstring(FH, I->segname, 16); - outaddr(FH, I->addr); - outaddr(FH, I->size); - outword(FH, I->offset); - outword(FH, I->align); - outword(FH, I->reloff); - outword(FH, I->nreloc); - outword(FH, I->flags); - outword(FH, I->reserved1); - outword(FH, I->reserved2); + FHOut.outstring(MOS->sectname, 16); + FHOut.outstring(MOS->segname, 16); + FHOut.outaddr(MOS->addr); + FHOut.outaddr(MOS->size); + FHOut.outword(MOS->offset); + FHOut.outword(MOS->align); + FHOut.outword(MOS->reloff); + FHOut.outword(MOS->nreloc); + FHOut.outword(MOS->flags); + FHOut.outword(MOS->reserved1); + FHOut.outword(MOS->reserved2); if (is64Bit) - outword(FH, I->reserved3); + FHOut.outword(MOS->reserved3); } - // Step #7: Emit LC_SYMTAB/LC_DYSYMTAB load commands - // FIXME: add size of relocs + // Step #8: Emit LC_SYMTAB/LC_DYSYMTAB load commands SymTab.symoff = currentAddr; SymTab.nsyms = SymbolTable.size(); SymTab.stroff = SymTab.symoff + SymT.size(); SymTab.strsize = StrT.size(); - outword(FH, SymTab.cmd); - outword(FH, SymTab.cmdsize); - outword(FH, SymTab.symoff); - outword(FH, SymTab.nsyms); - outword(FH, SymTab.stroff); - outword(FH, SymTab.strsize); + FHOut.outword(SymTab.cmd); + FHOut.outword(SymTab.cmdsize); + FHOut.outword(SymTab.symoff); + FHOut.outword(SymTab.nsyms); + FHOut.outword(SymTab.stroff); + FHOut.outword(SymTab.strsize); // FIXME: set DySymTab fields appropriately // We should probably just update these in BufferSymbolAndStringTable since // thats where we're partitioning up the different kinds of symbols. - outword(FH, DySymTab.cmd); - outword(FH, DySymTab.cmdsize); - outword(FH, DySymTab.ilocalsym); - outword(FH, DySymTab.nlocalsym); - outword(FH, DySymTab.iextdefsym); - outword(FH, DySymTab.nextdefsym); - outword(FH, DySymTab.iundefsym); - outword(FH, DySymTab.nundefsym); - outword(FH, DySymTab.tocoff); - outword(FH, DySymTab.ntoc); - outword(FH, DySymTab.modtaboff); - outword(FH, DySymTab.nmodtab); - outword(FH, DySymTab.extrefsymoff); - outword(FH, DySymTab.nextrefsyms); - outword(FH, DySymTab.indirectsymoff); - outword(FH, DySymTab.nindirectsyms); - outword(FH, DySymTab.extreloff); - outword(FH, DySymTab.nextrel); - outword(FH, DySymTab.locreloff); - outword(FH, DySymTab.nlocrel); + FHOut.outword(DySymTab.cmd); + FHOut.outword(DySymTab.cmdsize); + FHOut.outword(DySymTab.ilocalsym); + FHOut.outword(DySymTab.nlocalsym); + FHOut.outword(DySymTab.iextdefsym); + FHOut.outword(DySymTab.nextdefsym); + FHOut.outword(DySymTab.iundefsym); + FHOut.outword(DySymTab.nundefsym); + FHOut.outword(DySymTab.tocoff); + FHOut.outword(DySymTab.ntoc); + FHOut.outword(DySymTab.modtaboff); + FHOut.outword(DySymTab.nmodtab); + FHOut.outword(DySymTab.extrefsymoff); + FHOut.outword(DySymTab.nextrefsyms); + FHOut.outword(DySymTab.indirectsymoff); + FHOut.outword(DySymTab.nindirectsyms); + FHOut.outword(DySymTab.extreloff); + FHOut.outword(DySymTab.nextrel); + FHOut.outword(DySymTab.locreloff); + FHOut.outword(DySymTab.nlocrel); O.write((char*)&FH[0], FH.size()); } @@ -448,16 +606,19 @@ void MachOWriter::EmitHeaderAndLoadCommands() { /// EmitSections - Now that we have constructed the file header and load /// commands, emit the data for each section to the file. void MachOWriter::EmitSections() { - for (std::list::iterator I = SectionList.begin(), - E = SectionList.end(); I != E; ++I) { - O.write((char*)&I->SectionData[0], I->size); - } + for (std::vector::iterator I = SectionList.begin(), + E = SectionList.end(); I != E; ++I) + // Emit the contents of each section + O.write((char*)&(*I)->SectionData[0], (*I)->size); + for (std::vector::iterator I = SectionList.begin(), + E = SectionList.end(); I != E; ++I) + // Emit the relocation entry data for each section. + O.write((char*)&(*I)->RelocBuffer[0], (*I)->RelocBuffer.size()); } /// PartitionByLocal - Simple boolean predicate that returns true if Sym is /// a local symbol rather than an external symbol. bool MachOWriter::PartitionByLocal(const MachOSym &Sym) { - // FIXME: Not totally sure if private extern counts as external return (Sym.n_type & (MachOSym::N_EXT | MachOSym::N_PEXT)) == 0; } @@ -477,6 +638,17 @@ void MachOWriter::BufferSymbolAndStringTable() { // 2. defined external symbols (sorted by name) // 3. undefined external symbols (sorted by name) + // Before sorting the symbols, check the PendingGlobals for any undefined + // globals that need to be put in the symbol table. + for (std::vector::iterator I = PendingGlobals.begin(), + E = PendingGlobals.end(); I != E; ++I) { + if (GVOffset[*I] == 0 && GVSection[*I] == 0) { + MachOSym UndfSym(*I, Mang->getValueName(*I), MachOSym::NO_SECT, TM); + SymbolTable.push_back(UndfSym); + GVOffset[*I] = -1; + } + } + // Sort the symbols by name, so that when we partition the symbols by scope // of definition, we won't have to sort by name within each partition. std::sort(SymbolTable.begin(), SymbolTable.end(), MachOSymCmp()); @@ -495,10 +667,28 @@ void MachOWriter::BufferSymbolAndStringTable() { break; } } + + // Calculate the starting index for each of the local, extern defined, and + // undefined symbols, as well as the number of each to put in the LC_DYSYMTAB + // load command. + for (std::vector::iterator I = SymbolTable.begin(), + E = SymbolTable.end(); I != E; ++I) { + if (PartitionByLocal(*I)) { + ++DySymTab.nlocalsym; + ++DySymTab.iextdefsym; + ++DySymTab.iundefsym; + } else if (PartitionByDefined(*I)) { + ++DySymTab.nextdefsym; + ++DySymTab.iundefsym; + } else { + ++DySymTab.nundefsym; + } + } // Write out a leading zero byte when emitting string table, for n_strx == 0 // which means an empty string. - outbyte(StrT, 0); + OutputBuffer StrTOut(StrT, is64Bit, isLittleEndian); + StrTOut.outbyte(0); // The order of the string table is: // 1. strings for external symbols @@ -511,26 +701,234 @@ void MachOWriter::BufferSymbolAndStringTable() { I->n_strx = 0; } else { I->n_strx = StrT.size(); - outstring(StrT, I->GVName, I->GVName.length()+1); + StrTOut.outstring(I->GVName, I->GVName.length()+1); } } + OutputBuffer SymTOut(SymT, is64Bit, isLittleEndian); + + unsigned index = 0; for (std::vector::iterator I = SymbolTable.begin(), - E = SymbolTable.end(); I != E; ++I) { + E = SymbolTable.end(); I != E; ++I, ++index) { + // Add the section base address to the section offset in the n_value field + // to calculate the full address. + // FIXME: handle symbols where the n_value field is not the address + GlobalValue *GV = const_cast(I->GV); + if (GV && GVSection[GV]) + I->n_value += GVSection[GV]->addr; + if (GV && (GVOffset[GV] == -1)) + GVOffset[GV] = index; + // Emit nlist to buffer - outword(SymT, I->n_strx); - outbyte(SymT, I->n_type); - outbyte(SymT, I->n_sect); - outhalf(SymT, I->n_desc); - outaddr(SymT, I->n_value); + SymTOut.outword(I->n_strx); + SymTOut.outbyte(I->n_type); + SymTOut.outbyte(I->n_sect); + SymTOut.outhalf(I->n_desc); + SymTOut.outaddr(I->n_value); + } +} + +/// CalculateRelocations - For each MachineRelocation in the current section, +/// calculate the index of the section containing the object to be relocated, +/// and the offset into that section. From this information, create the +/// appropriate target-specific MachORelocation type and add buffer it to be +/// written out after we are finished writing out sections. +void MachOWriter::CalculateRelocations(MachOSection &MOS) { + for (unsigned i = 0, e = MOS.Relocations.size(); i != e; ++i) { + MachineRelocation &MR = MOS.Relocations[i]; + unsigned TargetSection = MR.getConstantVal(); + unsigned TargetAddr = 0; + unsigned TargetIndex = 0; + + // This is a scattered relocation entry if it points to a global value with + // a non-zero offset. + bool Scattered = false; + bool Extern = false; + + // Since we may not have seen the GlobalValue we were interested in yet at + // the time we emitted the relocation for it, fix it up now so that it + // points to the offset into the correct section. + if (MR.isGlobalValue()) { + GlobalValue *GV = MR.getGlobalValue(); + MachOSection *MOSPtr = GVSection[GV]; + intptr_t Offset = GVOffset[GV]; + + // If we have never seen the global before, it must be to a symbol + // defined in another module (N_UNDF). + if (!MOSPtr) { + // FIXME: need to append stub suffix + Extern = true; + TargetAddr = 0; + TargetIndex = GVOffset[GV]; + } else { + Scattered = TargetSection != 0; + TargetSection = MOSPtr->Index; + } + MR.setResultPointer((void*)Offset); + } + + // If the symbol is locally defined, pass in the address of the section and + // the section index to the code which will generate the target relocation. + if (!Extern) { + MachOSection &To = *SectionList[TargetSection - 1]; + TargetAddr = To.addr; + TargetIndex = To.Index; + } + + OutputBuffer RelocOut(MOS.RelocBuffer, is64Bit, isLittleEndian); + OutputBuffer SecOut(MOS.SectionData, is64Bit, isLittleEndian); + + MOS.nreloc += GetTargetRelocation(MR, MOS.Index, TargetAddr, TargetIndex, + RelocOut, SecOut, Scattered, Extern); } } -MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect) : - GV(gv), GVName(name), n_strx(0), n_type(sect == NO_SECT ? N_UNDF : N_SECT), - n_sect(sect), n_desc(0), n_value(0) { - // FIXME: take a target machine, and then add the appropriate prefix for - // the linkage type based on the TargetAsmInfo +// InitMem - Write the value of a Constant to the specified memory location, +// converting it into bytes and relocations. +void MachOWriter::InitMem(const Constant *C, void *Addr, intptr_t Offset, + const TargetData *TD, + std::vector &MRs) { + typedef std::pair CPair; + std::vector WorkList; + + WorkList.push_back(CPair(C,(intptr_t)Addr + Offset)); + + intptr_t ScatteredOffset = 0; + + while (!WorkList.empty()) { + const Constant *PC = WorkList.back().first; + intptr_t PA = WorkList.back().second; + WorkList.pop_back(); + + if (isa(PC)) { + continue; + } else if (const ConstantVector *CP = dyn_cast(PC)) { + unsigned ElementSize = TD->getTypeSize(CP->getType()->getElementType()); + for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i) + WorkList.push_back(CPair(CP->getOperand(i), PA+i*ElementSize)); + } else if (const ConstantExpr *CE = dyn_cast(PC)) { + // + // FIXME: Handle ConstantExpression. See EE::getConstantValue() + // + switch (CE->getOpcode()) { + case Instruction::GetElementPtr: { + SmallVector Indices(CE->op_begin()+1, CE->op_end()); + ScatteredOffset = TD->getIndexedOffset(CE->getOperand(0)->getType(), + &Indices[0], Indices.size()); + WorkList.push_back(CPair(CE->getOperand(0), PA)); + break; + } + case Instruction::Add: + default: + cerr << "ConstantExpr not handled as global var init: " << *CE << "\n"; + abort(); + break; + } + } else if (PC->getType()->isFirstClassType()) { + unsigned char *ptr = (unsigned char *)PA; + switch (PC->getType()->getTypeID()) { + case Type::IntegerTyID: { + unsigned NumBits = cast(PC->getType())->getBitWidth(); + uint64_t val = cast(PC)->getZExtValue(); + if (NumBits <= 8) + ptr[0] = val; + else if (NumBits <= 16) { + if (TD->isBigEndian()) + val = ByteSwap_16(val); + ptr[0] = val; + ptr[1] = val >> 8; + } else if (NumBits <= 32) { + if (TD->isBigEndian()) + val = ByteSwap_32(val); + ptr[0] = val; + ptr[1] = val >> 8; + ptr[2] = val >> 16; + ptr[3] = val >> 24; + } else if (NumBits <= 64) { + if (TD->isBigEndian()) + val = ByteSwap_64(val); + ptr[0] = val; + ptr[1] = val >> 8; + ptr[2] = val >> 16; + ptr[3] = val >> 24; + ptr[4] = val >> 32; + ptr[5] = val >> 40; + ptr[6] = val >> 48; + ptr[7] = val >> 56; + } else { + assert(0 && "Not implemented: bit widths > 64"); + } + break; + } + case Type::FloatTyID: { + uint32_t val = cast(PC)->getValueAPF().convertToAPInt(). + getZExtValue(); + if (TD->isBigEndian()) + val = ByteSwap_32(val); + ptr[0] = val; + ptr[1] = val >> 8; + ptr[2] = val >> 16; + ptr[3] = val >> 24; + break; + } + case Type::DoubleTyID: { + uint64_t val = cast(PC)->getValueAPF().convertToAPInt(). + getZExtValue(); + if (TD->isBigEndian()) + val = ByteSwap_64(val); + ptr[0] = val; + ptr[1] = val >> 8; + ptr[2] = val >> 16; + ptr[3] = val >> 24; + ptr[4] = val >> 32; + ptr[5] = val >> 40; + ptr[6] = val >> 48; + ptr[7] = val >> 56; + break; + } + case Type::PointerTyID: + if (isa(PC)) + memset(ptr, 0, TD->getPointerSize()); + else if (const GlobalValue* GV = dyn_cast(PC)) { + // FIXME: what about function stubs? + MRs.push_back(MachineRelocation::getGV(PA-(intptr_t)Addr, + MachineRelocation::VANILLA, + const_cast(GV), + ScatteredOffset)); + ScatteredOffset = 0; + } else + assert(0 && "Unknown constant pointer type!"); + break; + default: + cerr << "ERROR: Constant unimp for type: " << *PC->getType() << "\n"; + abort(); + } + } else if (isa(PC)) { + memset((void*)PA, 0, (size_t)TD->getTypeSize(PC->getType())); + } else if (const ConstantArray *CPA = dyn_cast(PC)) { + unsigned ElementSize = TD->getTypeSize(CPA->getType()->getElementType()); + for (unsigned i = 0, e = CPA->getNumOperands(); i != e; ++i) + WorkList.push_back(CPair(CPA->getOperand(i), PA+i*ElementSize)); + } else if (const ConstantStruct *CPS = dyn_cast(PC)) { + const StructLayout *SL = + TD->getStructLayout(cast(CPS->getType())); + for (unsigned i = 0, e = CPS->getNumOperands(); i != e; ++i) + WorkList.push_back(CPair(CPS->getOperand(i), + PA+SL->getElementOffset(i))); + } else { + cerr << "Bad Type: " << *PC->getType() << "\n"; + assert(0 && "Unknown constant type to initialize memory with!"); + } + } +} + +MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect, + TargetMachine &TM) : + GV(gv), n_strx(0), n_type(sect == NO_SECT ? N_UNDF : N_SECT), n_sect(sect), + n_desc(0), n_value(0) { + + const TargetAsmInfo *TAI = TM.getTargetAsmInfo(); + switch (GV->getLinkage()) { default: assert(0 && "Unexpected linkage type!"); @@ -539,9 +937,11 @@ MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect) : case GlobalValue::LinkOnceLinkage: assert(!isa(gv) && "Unexpected linkage type for Function!"); case GlobalValue::ExternalLinkage: - n_type |= N_EXT; + GVName = TAI->getGlobalPrefix() + name; + n_type |= GV->hasHiddenVisibility() ? N_PEXT : N_EXT; break; case GlobalValue::InternalLinkage: + GVName = TAI->getGlobalPrefix() + name; break; } }