mirror of
https://github.com/c64scene-ar/llvm-6502.git
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additional bug fixes: 1. The bug that everyone hit was a problem in the asmprinter where it would remove $stub but keep the L prefix on a name when emitting the indirect symbol. This is easy to fix by keeping the name of the stub and the name of the symbol in a StringMap instead of just keeping a StringSet and trying to reconstruct it late. 2. There was a problem printing the personality function. The current logic to print out the personality function from the DWARF information is a bit of a cesspool right now that duplicates a bunch of other logic in the asm printer. The short version of it is that it depends on emitting both the L and _ prefix for symbols (at least on darwin) and until I can untangle it, it is best to switch the mangler back to emitting both prefixes. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75646 91177308-0d34-0410-b5e6-96231b3b80d8
775 lines
28 KiB
C++
775 lines
28 KiB
C++
//===-- MachOWriter.cpp - Target-independent Mach-O Writer code -----------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the target-independent Mach-O writer. This file writes
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// out the Mach-O file in the following order:
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//
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// #1 FatHeader (universal-only)
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// #2 FatArch (universal-only, 1 per universal arch)
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// Per arch:
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// #3 Header
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// #4 Load Commands
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// #5 Sections
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// #6 Relocations
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// #7 Symbols
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// #8 Strings
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//
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//===----------------------------------------------------------------------===//
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#include "MachO.h"
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#include "MachOWriter.h"
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#include "MachOCodeEmitter.h"
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#include "llvm/Constants.h"
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#include "llvm/DerivedTypes.h"
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#include "llvm/Module.h"
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#include "llvm/PassManager.h"
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#include "llvm/Target/TargetAsmInfo.h"
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#include "llvm/Target/TargetData.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetMachOWriterInfo.h"
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#include "llvm/Support/Mangler.h"
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#include "llvm/Support/OutputBuffer.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/raw_ostream.h"
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namespace llvm {
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/// AddMachOWriter - Concrete function to add the Mach-O writer to the function
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/// pass manager.
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ObjectCodeEmitter *AddMachOWriter(PassManagerBase &PM,
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raw_ostream &O,
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TargetMachine &TM) {
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MachOWriter *MOW = new MachOWriter(O, TM);
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PM.add(MOW);
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return MOW->getObjectCodeEmitter();
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}
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//===----------------------------------------------------------------------===//
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// MachOWriter Implementation
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//===----------------------------------------------------------------------===//
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char MachOWriter::ID = 0;
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MachOWriter::MachOWriter(raw_ostream &o, TargetMachine &tm)
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: MachineFunctionPass(&ID), O(o), TM(tm) {
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is64Bit = TM.getTargetData()->getPointerSizeInBits() == 64;
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isLittleEndian = TM.getTargetData()->isLittleEndian();
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TAI = TM.getTargetAsmInfo();
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// Create the machine code emitter object for this target.
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MachOCE = new MachOCodeEmitter(*this, *getTextSection(true));
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}
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MachOWriter::~MachOWriter() {
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delete MachOCE;
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}
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bool MachOWriter::doInitialization(Module &M) {
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// Set the magic value, now that we know the pointer size and endianness
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Header.setMagic(isLittleEndian, is64Bit);
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// Set the file type
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// FIXME: this only works for object files, we do not support the creation
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// of dynamic libraries or executables at this time.
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Header.filetype = MachOHeader::MH_OBJECT;
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Mang = new Mangler(M);
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return false;
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}
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bool MachOWriter::runOnMachineFunction(MachineFunction &MF) {
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return false;
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}
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/// doFinalization - Now that the module has been completely processed, emit
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/// the Mach-O file to 'O'.
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bool MachOWriter::doFinalization(Module &M) {
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// FIXME: we don't handle debug info yet, we should probably do that.
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// Okay, the.text section has been completed, build the .data, .bss, and
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// "common" sections next.
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for (Module::global_iterator I = M.global_begin(), E = M.global_end();
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I != E; ++I)
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EmitGlobal(I);
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// Emit the header and load commands.
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EmitHeaderAndLoadCommands();
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// Emit the various sections and their relocation info.
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EmitSections();
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EmitRelocations();
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// Write the symbol table and the string table to the end of the file.
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O.write((char*)&SymT[0], SymT.size());
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O.write((char*)&StrT[0], StrT.size());
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// We are done with the abstract symbols.
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SectionList.clear();
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SymbolTable.clear();
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DynamicSymbolTable.clear();
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// Release the name mangler object.
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delete Mang; Mang = 0;
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return false;
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}
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// getConstSection - Get constant section for Constant 'C'
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MachOSection *MachOWriter::getConstSection(Constant *C) {
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const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
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if (CVA && CVA->isCString())
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return getSection("__TEXT", "__cstring",
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MachOSection::S_CSTRING_LITERALS);
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const Type *Ty = C->getType();
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if (Ty->isPrimitiveType() || Ty->isInteger()) {
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unsigned Size = TM.getTargetData()->getTypeAllocSize(Ty);
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switch(Size) {
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default: break; // Fall through to __TEXT,__const
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case 4:
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return getSection("__TEXT", "__literal4",
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MachOSection::S_4BYTE_LITERALS);
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case 8:
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return getSection("__TEXT", "__literal8",
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MachOSection::S_8BYTE_LITERALS);
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case 16:
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return getSection("__TEXT", "__literal16",
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MachOSection::S_16BYTE_LITERALS);
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}
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}
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return getSection("__TEXT", "__const");
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}
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// getJumpTableSection - Select the Jump Table section
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MachOSection *MachOWriter::getJumpTableSection() {
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if (TM.getRelocationModel() == Reloc::PIC_)
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return getTextSection(false);
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else
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return getSection("__TEXT", "__const");
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}
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// getSection - Return the section with the specified name, creating a new
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// section if one does not already exist.
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MachOSection *MachOWriter::getSection(const std::string &seg,
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const std::string §,
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unsigned Flags /* = 0 */ ) {
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MachOSection *MOS = SectionLookup[seg+sect];
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if (MOS) return MOS;
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MOS = new MachOSection(seg, sect);
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SectionList.push_back(MOS);
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MOS->Index = SectionList.size();
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MOS->flags = MachOSection::S_REGULAR | Flags;
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SectionLookup[seg+sect] = MOS;
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return MOS;
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}
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// getTextSection - Return text section with different flags for code/data
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MachOSection *MachOWriter::getTextSection(bool isCode /* = true */ ) {
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if (isCode)
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return getSection("__TEXT", "__text",
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MachOSection::S_ATTR_PURE_INSTRUCTIONS |
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MachOSection::S_ATTR_SOME_INSTRUCTIONS);
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else
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return getSection("__TEXT", "__text");
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}
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MachOSection *MachOWriter::getBSSSection() {
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return getSection("__DATA", "__bss", MachOSection::S_ZEROFILL);
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}
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// GetJTRelocation - Get a relocation a new BB relocation based
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// on target information.
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MachineRelocation MachOWriter::GetJTRelocation(unsigned Offset,
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MachineBasicBlock *MBB) const {
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return TM.getMachOWriterInfo()->GetJTRelocation(Offset, MBB);
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}
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// GetTargetRelocation - Returns the number of relocations.
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unsigned MachOWriter::GetTargetRelocation(MachineRelocation &MR,
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unsigned FromIdx, unsigned ToAddr,
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unsigned ToIndex, OutputBuffer &RelocOut,
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OutputBuffer &SecOut, bool Scattered,
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bool Extern) {
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return TM.getMachOWriterInfo()->GetTargetRelocation(MR, FromIdx, ToAddr,
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ToIndex, RelocOut,
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SecOut, Scattered,
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Extern);
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}
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void MachOWriter::AddSymbolToSection(MachOSection *Sec, GlobalVariable *GV) {
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const Type *Ty = GV->getType()->getElementType();
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unsigned Size = TM.getTargetData()->getTypeAllocSize(Ty);
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unsigned Align = TM.getTargetData()->getPreferredAlignment(GV);
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// Reserve space in the .bss section for this symbol while maintaining the
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// desired section alignment, which must be at least as much as required by
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// this symbol.
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OutputBuffer SecDataOut(Sec->getData(), is64Bit, isLittleEndian);
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if (Align) {
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Align = Log2_32(Align);
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Sec->align = std::max(unsigned(Sec->align), Align);
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Sec->emitAlignment(Sec->align);
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}
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// Globals without external linkage apparently do not go in the symbol table.
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if (!GV->hasLocalLinkage()) {
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MachOSym Sym(GV, Mang->getMangledName(GV), Sec->Index, TAI);
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Sym.n_value = Sec->size();
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SymbolTable.push_back(Sym);
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}
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// Record the offset of the symbol, and then allocate space for it.
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// FIXME: remove when we have unified size + output buffer
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// Now that we know what section the GlovalVariable is going to be emitted
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// into, update our mappings.
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// FIXME: We may also need to update this when outputting non-GlobalVariable
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// GlobalValues such as functions.
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GVSection[GV] = Sec;
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GVOffset[GV] = Sec->size();
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// Allocate space in the section for the global.
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for (unsigned i = 0; i < Size; ++i)
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SecDataOut.outbyte(0);
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}
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void MachOWriter::EmitGlobal(GlobalVariable *GV) {
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const Type *Ty = GV->getType()->getElementType();
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unsigned Size = TM.getTargetData()->getTypeAllocSize(Ty);
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bool NoInit = !GV->hasInitializer();
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// If this global has a zero initializer, it is part of the .bss or common
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// section.
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if (NoInit || GV->getInitializer()->isNullValue()) {
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// If this global is part of the common block, add it now. Variables are
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// part of the common block if they are zero initialized and allowed to be
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// merged with other symbols.
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if (NoInit || GV->hasLinkOnceLinkage() || GV->hasWeakLinkage() ||
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GV->hasCommonLinkage()) {
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MachOSym ExtOrCommonSym(GV, Mang->getMangledName(GV),
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MachOSym::NO_SECT, TAI);
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// For undefined (N_UNDF) external (N_EXT) types, n_value is the size in
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// bytes of the symbol.
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ExtOrCommonSym.n_value = Size;
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SymbolTable.push_back(ExtOrCommonSym);
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// Remember that we've seen this symbol
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GVOffset[GV] = Size;
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return;
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}
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// Otherwise, this symbol is part of the .bss section.
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MachOSection *BSS = getBSSSection();
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AddSymbolToSection(BSS, GV);
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return;
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}
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// Scalar read-only data goes in a literal section if the scalar is 4, 8, or
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// 16 bytes, or a cstring. Other read only data goes into a regular const
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// section. Read-write data goes in the data section.
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MachOSection *Sec = GV->isConstant() ? getConstSection(GV->getInitializer()) :
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getDataSection();
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AddSymbolToSection(Sec, GV);
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InitMem(GV->getInitializer(), GVOffset[GV], TM.getTargetData(), Sec);
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}
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void MachOWriter::EmitHeaderAndLoadCommands() {
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// Step #0: Fill in the segment load command size, since we need it to figure
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// out the rest of the header fields
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MachOSegment SEG("", is64Bit);
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SEG.nsects = SectionList.size();
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SEG.cmdsize = SEG.cmdSize(is64Bit) +
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SEG.nsects * SectionList[0]->cmdSize(is64Bit);
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// Step #1: calculate the number of load commands. We always have at least
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// one, for the LC_SEGMENT load command, plus two for the normal
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// and dynamic symbol tables, if there are any symbols.
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Header.ncmds = SymbolTable.empty() ? 1 : 3;
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// Step #2: calculate the size of the load commands
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Header.sizeofcmds = SEG.cmdsize;
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if (!SymbolTable.empty())
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Header.sizeofcmds += SymTab.cmdsize + DySymTab.cmdsize;
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// Step #3: write the header to the file
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// Local alias to shortenify coming code.
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std::vector<unsigned char> &FH = Header.HeaderData;
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OutputBuffer FHOut(FH, is64Bit, isLittleEndian);
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FHOut.outword(Header.magic);
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FHOut.outword(TM.getMachOWriterInfo()->getCPUType());
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FHOut.outword(TM.getMachOWriterInfo()->getCPUSubType());
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FHOut.outword(Header.filetype);
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FHOut.outword(Header.ncmds);
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FHOut.outword(Header.sizeofcmds);
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FHOut.outword(Header.flags);
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if (is64Bit)
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FHOut.outword(Header.reserved);
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// Step #4: Finish filling in the segment load command and write it out
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for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
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E = SectionList.end(); I != E; ++I)
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SEG.filesize += (*I)->size();
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SEG.vmsize = SEG.filesize;
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SEG.fileoff = Header.cmdSize(is64Bit) + Header.sizeofcmds;
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FHOut.outword(SEG.cmd);
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FHOut.outword(SEG.cmdsize);
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FHOut.outstring(SEG.segname, 16);
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FHOut.outaddr(SEG.vmaddr);
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FHOut.outaddr(SEG.vmsize);
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FHOut.outaddr(SEG.fileoff);
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FHOut.outaddr(SEG.filesize);
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FHOut.outword(SEG.maxprot);
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FHOut.outword(SEG.initprot);
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FHOut.outword(SEG.nsects);
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FHOut.outword(SEG.flags);
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// Step #5: Finish filling in the fields of the MachOSections
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uint64_t currentAddr = 0;
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for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
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E = SectionList.end(); I != E; ++I) {
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MachOSection *MOS = *I;
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MOS->addr = currentAddr;
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MOS->offset = currentAddr + SEG.fileoff;
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// FIXME: do we need to do something with alignment here?
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currentAddr += MOS->size();
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}
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// Step #6: Emit the symbol table to temporary buffers, so that we know the
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// size of the string table when we write the next load command. This also
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// sorts and assigns indices to each of the symbols, which is necessary for
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// emitting relocations to externally-defined objects.
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BufferSymbolAndStringTable();
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// Step #7: Calculate the number of relocations for each section and write out
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// the section commands for each section
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currentAddr += SEG.fileoff;
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for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
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E = SectionList.end(); I != E; ++I) {
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MachOSection *MOS = *I;
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// Convert the relocations to target-specific relocations, and fill in the
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// relocation offset for this section.
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CalculateRelocations(*MOS);
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MOS->reloff = MOS->nreloc ? currentAddr : 0;
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currentAddr += MOS->nreloc * 8;
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// write the finalized section command to the output buffer
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FHOut.outstring(MOS->sectname, 16);
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FHOut.outstring(MOS->segname, 16);
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FHOut.outaddr(MOS->addr);
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FHOut.outaddr(MOS->size());
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FHOut.outword(MOS->offset);
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FHOut.outword(MOS->align);
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FHOut.outword(MOS->reloff);
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FHOut.outword(MOS->nreloc);
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FHOut.outword(MOS->flags);
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FHOut.outword(MOS->reserved1);
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FHOut.outword(MOS->reserved2);
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if (is64Bit)
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FHOut.outword(MOS->reserved3);
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}
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// Step #8: Emit LC_SYMTAB/LC_DYSYMTAB load commands
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SymTab.symoff = currentAddr;
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SymTab.nsyms = SymbolTable.size();
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SymTab.stroff = SymTab.symoff + SymT.size();
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SymTab.strsize = StrT.size();
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FHOut.outword(SymTab.cmd);
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FHOut.outword(SymTab.cmdsize);
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FHOut.outword(SymTab.symoff);
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FHOut.outword(SymTab.nsyms);
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FHOut.outword(SymTab.stroff);
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FHOut.outword(SymTab.strsize);
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// FIXME: set DySymTab fields appropriately
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// We should probably just update these in BufferSymbolAndStringTable since
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// thats where we're partitioning up the different kinds of symbols.
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FHOut.outword(DySymTab.cmd);
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FHOut.outword(DySymTab.cmdsize);
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FHOut.outword(DySymTab.ilocalsym);
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FHOut.outword(DySymTab.nlocalsym);
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FHOut.outword(DySymTab.iextdefsym);
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FHOut.outword(DySymTab.nextdefsym);
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FHOut.outword(DySymTab.iundefsym);
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FHOut.outword(DySymTab.nundefsym);
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FHOut.outword(DySymTab.tocoff);
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FHOut.outword(DySymTab.ntoc);
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FHOut.outword(DySymTab.modtaboff);
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FHOut.outword(DySymTab.nmodtab);
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FHOut.outword(DySymTab.extrefsymoff);
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FHOut.outword(DySymTab.nextrefsyms);
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FHOut.outword(DySymTab.indirectsymoff);
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FHOut.outword(DySymTab.nindirectsyms);
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FHOut.outword(DySymTab.extreloff);
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FHOut.outword(DySymTab.nextrel);
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FHOut.outword(DySymTab.locreloff);
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FHOut.outword(DySymTab.nlocrel);
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O.write((char*)&FH[0], FH.size());
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}
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/// EmitSections - Now that we have constructed the file header and load
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/// commands, emit the data for each section to the file.
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void MachOWriter::EmitSections() {
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for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
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E = SectionList.end(); I != E; ++I)
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// Emit the contents of each section
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if ((*I)->size())
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O.write((char*)&(*I)->getData()[0], (*I)->size());
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}
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/// EmitRelocations - emit relocation data from buffer.
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void MachOWriter::EmitRelocations() {
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for (std::vector<MachOSection*>::iterator I = SectionList.begin(),
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E = SectionList.end(); I != E; ++I)
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// Emit the relocation entry data for each section.
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if ((*I)->RelocBuffer.size())
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O.write((char*)&(*I)->RelocBuffer[0], (*I)->RelocBuffer.size());
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}
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/// BufferSymbolAndStringTable - Sort the symbols we encountered and assign them
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/// each a string table index so that they appear in the correct order in the
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/// output file.
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void MachOWriter::BufferSymbolAndStringTable() {
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// The order of the symbol table is:
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// 1. local symbols
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// 2. defined external symbols (sorted by name)
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// 3. undefined external symbols (sorted by name)
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// Before sorting the symbols, check the PendingGlobals for any undefined
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|
// globals that need to be put in the symbol table.
|
|
for (std::vector<GlobalValue*>::iterator I = PendingGlobals.begin(),
|
|
E = PendingGlobals.end(); I != E; ++I) {
|
|
if (GVOffset[*I] == 0 && GVSection[*I] == 0) {
|
|
MachOSym UndfSym(*I, Mang->getMangledName(*I), MachOSym::NO_SECT, TAI);
|
|
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(), MachOSym::SymCmp());
|
|
|
|
// Parition the symbol table entries so that all local symbols come before
|
|
// all symbols with external linkage. { 1 | 2 3 }
|
|
std::partition(SymbolTable.begin(), SymbolTable.end(),
|
|
MachOSym::PartitionByLocal);
|
|
|
|
// Advance iterator to beginning of external symbols and partition so that
|
|
// all external symbols defined in this module come before all external
|
|
// symbols defined elsewhere. { 1 | 2 | 3 }
|
|
for (std::vector<MachOSym>::iterator I = SymbolTable.begin(),
|
|
E = SymbolTable.end(); I != E; ++I) {
|
|
if (!MachOSym::PartitionByLocal(*I)) {
|
|
std::partition(I, E, MachOSym::PartitionByDefined);
|
|
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<MachOSym>::iterator I = SymbolTable.begin(),
|
|
E = SymbolTable.end(); I != E; ++I) {
|
|
if (MachOSym::PartitionByLocal(*I)) {
|
|
++DySymTab.nlocalsym;
|
|
++DySymTab.iextdefsym;
|
|
++DySymTab.iundefsym;
|
|
} else if (MachOSym::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.
|
|
OutputBuffer StrTOut(StrT, is64Bit, isLittleEndian);
|
|
StrTOut.outbyte(0);
|
|
|
|
// The order of the string table is:
|
|
// 1. strings for external symbols
|
|
// 2. strings for local symbols
|
|
// Since this is the opposite order from the symbol table, which we have just
|
|
// sorted, we can walk the symbol table backwards to output the string table.
|
|
for (std::vector<MachOSym>::reverse_iterator I = SymbolTable.rbegin(),
|
|
E = SymbolTable.rend(); I != E; ++I) {
|
|
if (I->GVName == "") {
|
|
I->n_strx = 0;
|
|
} else {
|
|
I->n_strx = StrT.size();
|
|
StrTOut.outstring(I->GVName, I->GVName.length()+1);
|
|
}
|
|
}
|
|
|
|
OutputBuffer SymTOut(SymT, is64Bit, isLittleEndian);
|
|
|
|
unsigned index = 0;
|
|
for (std::vector<MachOSym>::iterator I = SymbolTable.begin(),
|
|
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<GlobalValue*>(I->GV);
|
|
if (GV && GVSection[GV])
|
|
I->n_value += GVSection[GV]->addr;
|
|
if (GV && (GVOffset[GV] == -1))
|
|
GVOffset[GV] = index;
|
|
|
|
// Emit nlist to buffer
|
|
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) {
|
|
std::vector<MachineRelocation> Relocations = MOS.getRelocations();
|
|
for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
|
|
MachineRelocation &MR = 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.getData(), is64Bit, isLittleEndian);
|
|
|
|
MOS.nreloc += GetTargetRelocation(MR, MOS.Index, TargetAddr, TargetIndex,
|
|
RelocOut, SecOut, Scattered, Extern);
|
|
}
|
|
}
|
|
|
|
// InitMem - Write the value of a Constant to the specified memory location,
|
|
// converting it into bytes and relocations.
|
|
void MachOWriter::InitMem(const Constant *C, uintptr_t Offset,
|
|
const TargetData *TD, MachOSection* mos) {
|
|
typedef std::pair<const Constant*, intptr_t> CPair;
|
|
std::vector<CPair> WorkList;
|
|
uint8_t *Addr = &mos->getData()[0];
|
|
|
|
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<UndefValue>(PC)) {
|
|
continue;
|
|
} else if (const ConstantVector *CP = dyn_cast<ConstantVector>(PC)) {
|
|
unsigned ElementSize =
|
|
TD->getTypeAllocSize(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<ConstantExpr>(PC)) {
|
|
//
|
|
// FIXME: Handle ConstantExpression. See EE::getConstantValue()
|
|
//
|
|
switch (CE->getOpcode()) {
|
|
case Instruction::GetElementPtr: {
|
|
SmallVector<Value*, 8> 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";
|
|
llvm_unreachable(0);
|
|
}
|
|
} else if (PC->getType()->isSingleValueType()) {
|
|
unsigned char *ptr = (unsigned char *)PA;
|
|
switch (PC->getType()->getTypeID()) {
|
|
case Type::IntegerTyID: {
|
|
unsigned NumBits = cast<IntegerType>(PC->getType())->getBitWidth();
|
|
uint64_t val = cast<ConstantInt>(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 {
|
|
llvm_unreachable("Not implemented: bit widths > 64");
|
|
}
|
|
break;
|
|
}
|
|
case Type::FloatTyID: {
|
|
uint32_t val = cast<ConstantFP>(PC)->getValueAPF().bitcastToAPInt().
|
|
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<ConstantFP>(PC)->getValueAPF().bitcastToAPInt().
|
|
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<ConstantPointerNull>(PC))
|
|
memset(ptr, 0, TD->getPointerSize());
|
|
else if (const GlobalValue* GV = dyn_cast<GlobalValue>(PC)) {
|
|
// FIXME: what about function stubs?
|
|
mos->addRelocation(MachineRelocation::getGV(PA-(intptr_t)Addr,
|
|
MachineRelocation::VANILLA,
|
|
const_cast<GlobalValue*>(GV),
|
|
ScatteredOffset));
|
|
ScatteredOffset = 0;
|
|
} else
|
|
llvm_unreachable("Unknown constant pointer type!");
|
|
break;
|
|
default:
|
|
std::string msg;
|
|
raw_string_ostream Msg(msg);
|
|
Msg << "ERROR: Constant unimp for type: " << *PC->getType();
|
|
llvm_report_error(Msg.str());
|
|
}
|
|
} else if (isa<ConstantAggregateZero>(PC)) {
|
|
memset((void*)PA, 0, (size_t)TD->getTypeAllocSize(PC->getType()));
|
|
} else if (const ConstantArray *CPA = dyn_cast<ConstantArray>(PC)) {
|
|
unsigned ElementSize =
|
|
TD->getTypeAllocSize(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<ConstantStruct>(PC)) {
|
|
const StructLayout *SL =
|
|
TD->getStructLayout(cast<StructType>(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";
|
|
llvm_unreachable("Unknown constant type to initialize memory with!");
|
|
}
|
|
}
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// MachOSym Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
MachOSym::MachOSym(const GlobalValue *gv, std::string name, uint8_t sect,
|
|
const TargetAsmInfo *TAI) :
|
|
GV(gv), n_strx(0), n_type(sect == NO_SECT ? N_UNDF : N_SECT), n_sect(sect),
|
|
n_desc(0), n_value(0) {
|
|
|
|
switch (GV->getLinkage()) {
|
|
default:
|
|
llvm_unreachable("Unexpected linkage type!");
|
|
break;
|
|
case GlobalValue::WeakAnyLinkage:
|
|
case GlobalValue::WeakODRLinkage:
|
|
case GlobalValue::LinkOnceAnyLinkage:
|
|
case GlobalValue::LinkOnceODRLinkage:
|
|
case GlobalValue::CommonLinkage:
|
|
assert(!isa<Function>(gv) && "Unexpected linkage type for Function!");
|
|
case GlobalValue::ExternalLinkage:
|
|
GVName = TAI->getGlobalPrefix() + name;
|
|
n_type |= GV->hasHiddenVisibility() ? N_PEXT : N_EXT;
|
|
break;
|
|
case GlobalValue::PrivateLinkage:
|
|
GVName = TAI->getPrivateGlobalPrefix() + name;
|
|
break;
|
|
case GlobalValue::InternalLinkage:
|
|
GVName = TAI->getGlobalPrefix() + name;
|
|
break;
|
|
}
|
|
}
|
|
|
|
} // end namespace llvm
|
|
|