path: root/lib/MC/MCAssembler.cpp

//===- lib/MC/MCAssembler.cpp - Assembler Backend Implementation ----------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#define DEBUG_TYPE "assembler"
#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/MC/MCValue.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MachO.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Debug.h"

// FIXME: Gross.
#include "../Target/X86/X86FixupKinds.h"

#include <vector>
using namespace llvm;

class MachObjectWriter;

STATISTIC(EmittedFragments, "Number of emitted assembler fragments");

// FIXME FIXME FIXME: There are number of places in this file where we convert
// what is a 64-bit assembler value used for computation into a value in the
// object file, which may truncate it. We should detect that truncation where
// invalid and report errors back.

static void WriteFileData(raw_ostream &OS, const MCSectionData &SD,
                          MachObjectWriter &MOW);

/// isVirtualSection - Check if this is a section which does not actually exist
/// in the object file.
static bool isVirtualSection(const MCSection &Section) {
  // FIXME: Lame.
  const MCSectionMachO &SMO = static_cast<const MCSectionMachO&>(Section);
  unsigned Type = SMO.getTypeAndAttributes() & MCSectionMachO::SECTION_TYPE;
  return (Type == MCSectionMachO::S_ZEROFILL);
}

static unsigned getFixupKindLog2Size(MCFixupKind Kind) {
  switch (Kind) {
  default: llvm_unreachable("invalid fixup kind!");
  case X86::reloc_pcrel_1byte:
  case FK_Data_1: return 0;
  case FK_Data_2: return 1;
  case X86::reloc_pcrel_4byte:
  case X86::reloc_riprel_4byte:
  case FK_Data_4: return 2;
  case FK_Data_8: return 3;
  }
}

sta