llvm/lib/Target/X86/X86TargetObjectFile.cpp

   1 //===-- X86TargetObjectFile.cpp - X86 Object Info -------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "X86TargetObjectFile.h"
  10 #include "llvm/BinaryFormat/Dwarf.h"
  11 #include "llvm/MC/MCExpr.h"
  12 #include "llvm/MC/MCValue.h"
  13 #include "llvm/Target/TargetMachine.h"
  14
  15 using namespace llvm;
  16 using namespace dwarf;
  17
  18 const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference(
  19     const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM,
  20     MachineModuleInfo *MMI, MCStreamer &Streamer) const {
  21
  22   // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
  23   // is an indirect pc-relative reference.
  24   if ((Encoding & DW_EH_PE_indirect) && (Encoding & DW_EH_PE_pcrel)) {
  25     const MCSymbol *Sym = TM.getSymbol(GV);
  26     const MCExpr *Res =
  27       MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
  28     const MCExpr *Four = MCConstantExpr::create(4, getContext());
  29     return MCBinaryExpr::createAdd(Res, Four, getContext());
  30   }
  31
  32   return TargetLoweringObjectFileMachO::getTTypeGlobalReference(
  33       GV, Encoding, TM, MMI, Streamer);
  34 }
  35
  36 MCSymbol *X86_64MachoTargetObjectFile::getCFIPersonalitySymbol(
  37     const GlobalValue *GV, const TargetMachine &TM,
  38     MachineModuleInfo *MMI) const {
  39   return TM.getSymbol(GV);
  40 }
  41
  42 const MCExpr *X86_64MachoTargetObjectFile::getIndirectSymViaGOTPCRel(
  43     const GlobalValue *GV, const MCSymbol *Sym, const MCValue &MV,
  44     int64_t Offset, MachineModuleInfo *MMI, MCStreamer &Streamer) const {
  45   // On Darwin/X86-64, we need to use foo@GOTPCREL+4 to access the got entry
  46   // from a data section. In case there's an additional offset, then use
  47   // foo@GOTPCREL+4+<offset>.
  48   unsigned FinalOff = Offset+MV.getConstant()+4;
  49   const MCExpr *Res =
  50     MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
  51   const MCExpr *Off = MCConstantExpr::create(FinalOff, getContext());
  52   return MCBinaryExpr::createAdd(Res, Off, getContext());
  53 }
  54
  55 const MCExpr *X86ELFTargetObjectFile::getDebugThreadLocalSymbol(
  56     const MCSymbol *Sym) const {
  57   return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext());
  58 }
  59
  60 const MCExpr *X86_64ELFTargetObjectFile::getIndirectSymViaGOTPCRel(
  61     const GlobalValue *GV, const MCSymbol *Sym, const MCValue &MV,
  62     int64_t Offset, MachineModuleInfo *MMI, MCStreamer &Streamer) const {
  63   int64_t FinalOffset = Offset + MV.getConstant();
  64   const MCExpr *Res =
  65       MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
  66   const MCExpr *Off = MCConstantExpr::create(FinalOffset, getContext());
  67   return MCBinaryExpr::createAdd(Res, Off, getContext());
  68 }