lib/Target/X86/X86TargetObjectFile.cpp

   1 //===-- llvm/Target/X86/X86TargetObjectFile.cpp - X86 Object Info ---------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "X86MCTargetExpr.h"
  11 #include "X86TargetObjectFile.h"
  12 #include "X86TargetMachine.h"
  13 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
  14 #include "llvm/MC/MCContext.h"
  15 #include "llvm/MC/MCSectionMachO.h"
  16 #include "llvm/Target/Mangler.h"
  17 #include "llvm/ADT/SmallString.h"
  18 #include "llvm/Support/Dwarf.h"
  19 using namespace llvm;
  20 using namespace dwarf;
  21
  22 void X86_MachoTargetObjectFile::Initialize(MCContext &Ctx,
  23                                            const TargetMachine &TM) {
  24   TargetLoweringObjectFileMachO::Initialize(Ctx, TM);
  25
  26   // Exception Handling.
  27   LSDASection = getMachOSection("__TEXT", "__gcc_except_tab", 0,
  28                                 SectionKind::getReadOnlyWithRel());
  29 }
  30
  31 unsigned X86_MachoTargetObjectFile::getTTypeEncoding() const {
  32   return DW_EH_PE_indirect | DW_EH_PE_pcrel | DW_EH_PE_sdata4;
  33 }
  34
  35 const MCExpr *X8664_MachoTargetObjectFile::
  36 getExprForDwarfGlobalReference(const GlobalValue *GV, Mangler *Mang,
  37                                MachineModuleInfo *MMI, unsigned Encoding,
  38                                MCStreamer &Streamer) const {
  39
  40   // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
  41   // is an indirect pc-relative reference.
  42   if (Encoding & (DW_EH_PE_indirect | DW_EH_PE_pcrel)) {
  43     const MCSymbol *Sym = Mang->getSymbol(GV);
  44     const MCExpr *Res =
  45       X86MCTargetExpr::Create(Sym, X86MCTargetExpr::GOTPCREL, getContext());
  46     const MCExpr *Four = MCConstantExpr::Create(4, getContext());
  47     return MCBinaryExpr::CreateAdd(Res, Four, getContext());
  48   }
  49
  50   return TargetLoweringObjectFileMachO::
  51     getExprForDwarfGlobalReference(GV, Mang, MMI, Encoding, Streamer);
  52 }
  53
  54 unsigned X8632_ELFTargetObjectFile::getPersonalityEncoding() const {
  55   if (TM.getRelocationModel() == Reloc::PIC_)
  56     return DW_EH_PE_indirect | DW_EH_PE_pcrel | DW_EH_PE_sdata4;
  57   else
  58     return DW_EH_PE_absptr;
  59 }
  60
  61 unsigned X8632_ELFTargetObjectFile::getLSDAEncoding() const {
  62   if (TM.getRelocationModel() == Reloc::PIC_)
  63     return DW_EH_PE_pcrel | DW_EH_PE_sdata4;
  64   else
  65     return DW_EH_PE_absptr;
  66 }
  67
  68 unsigned X8632_ELFTargetObjectFile::getFDEEncoding() const {
  69   if (TM.getRelocationModel() == Reloc::PIC_)
  70     return DW_EH_PE_pcrel | DW_EH_PE_sdata4;
  71   else
  72     return DW_EH_PE_absptr;
  73 }
  74
  75 unsigned X8632_ELFTargetObjectFile::getTTypeEncoding() const {
  76   if (TM.getRelocationModel() == Reloc::PIC_)
  77     return DW_EH_PE_indirect | DW_EH_PE_pcrel | DW_EH_PE_sdata4;
  78   else
  79     return DW_EH_PE_absptr;
  80 }
  81
  82 unsigned X8664_ELFTargetObjectFile::getPersonalityEncoding() const {
  83   CodeModel::Model Model = TM.getCodeModel();
  84   if (TM.getRelocationModel() == Reloc::PIC_)
  85     return DW_EH_PE_indirect | DW_EH_PE_pcrel | (Model == CodeModel::Small ||
  86                                                  Model == CodeModel::Medium ?
  87                                             DW_EH_PE_sdata4 : DW_EH_PE_sdata8);
  88
  89   if (Model == CodeModel::Small || Model == CodeModel::Medium)
  90     return DW_EH_PE_udata4;
  91
  92   return DW_EH_PE_absptr;
  93 }
  94
  95 unsigned X8664_ELFTargetObjectFile::getLSDAEncoding() const {
  96   CodeModel::Model Model = TM.getCodeModel();
  97   if (TM.getRelocationModel() == Reloc::PIC_)
  98     return DW_EH_PE_pcrel | (Model == CodeModel::Small ?
  99                              DW_EH_PE_sdata4 : DW_EH_PE_sdata8);
 100
 101   if (Model == CodeModel::Small)
 102     return DW_EH_PE_udata4;
 103
 104   return DW_EH_PE_absptr;
 105 }
 106
 107 unsigned X8664_ELFTargetObjectFile::getFDEEncoding() const {
 108   CodeModel::Model Model = TM.getCodeModel();
 109   if (TM.getRelocationModel() == Reloc::PIC_)
 110     return DW_EH_PE_pcrel | (Model == CodeModel::Small ||
 111                              Model == CodeModel::Medium ?
 112                              DW_EH_PE_sdata4 : DW_EH_PE_sdata8);
 113
 114   if (Model == CodeModel::Small || Model == CodeModel::Medium)
 115     return DW_EH_PE_udata4;
 116
 117   return DW_EH_PE_absptr;
 118 }
 119
 120 unsigned X8664_ELFTargetObjectFile::getTTypeEncoding() const {
 121   CodeModel::Model Model = TM.getCodeModel();
 122   if (TM.getRelocationModel() == Reloc::PIC_)
 123     return DW_EH_PE_indirect | DW_EH_PE_pcrel | (Model == CodeModel::Small ||
 124                                                  Model == CodeModel::Medium ?
 125                                             DW_EH_PE_sdata4 : DW_EH_PE_sdata8);
 126
 127   if (Model == CodeModel::Small)
 128     return DW_EH_PE_udata4;
 129
 130   return DW_EH_PE_absptr;
 131 }