LLVM  9.0.0svn
X86TargetObjectFile.cpp
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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/ADT/StringExtras.h"
11 #include "llvm/BinaryFormat/COFF.h"
14 #include "llvm/IR/Mangler.h"
15 #include "llvm/IR/Operator.h"
16 #include "llvm/MC/MCContext.h"
17 #include "llvm/MC/MCExpr.h"
18 #include "llvm/MC/MCSectionCOFF.h"
19 #include "llvm/MC/MCSectionELF.h"
20 #include "llvm/MC/MCValue.h"
21 
22 using namespace llvm;
23 using namespace dwarf;
24 
26  const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM,
27  MachineModuleInfo *MMI, MCStreamer &Streamer) const {
28 
29  // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
30  // is an indirect pc-relative reference.
31  if ((Encoding & DW_EH_PE_indirect) && (Encoding & DW_EH_PE_pcrel)) {
32  const MCSymbol *Sym = TM.getSymbol(GV);
33  const MCExpr *Res =
35  const MCExpr *Four = MCConstantExpr::create(4, getContext());
36  return MCBinaryExpr::createAdd(Res, Four, getContext());
37  }
38 
40  GV, Encoding, TM, MMI, Streamer);
41 }
42 
44  const GlobalValue *GV, const TargetMachine &TM,
45  MachineModuleInfo *MMI) const {
46  return TM.getSymbol(GV);
47 }
48 
50  const MCSymbol *Sym, const MCValue &MV, int64_t Offset,
51  MachineModuleInfo *MMI, MCStreamer &Streamer) const {
52  // On Darwin/X86-64, we need to use foo@GOTPCREL+4 to access the got entry
53  // from a data section. In case there's an additional offset, then use
54  // foo@GOTPCREL+4+<offset>.
55  unsigned FinalOff = Offset+MV.getConstant()+4;
56  const MCExpr *Res =
58  const MCExpr *Off = MCConstantExpr::create(FinalOff, getContext());
59  return MCBinaryExpr::createAdd(Res, Off, getContext());
60 }
61 
63  const MCSymbol *Sym) const {
64  return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext());
65 }
66 
67 void
68 X86FreeBSDTargetObjectFile::Initialize(MCContext &Ctx,
69  const TargetMachine &TM) {
71  InitializeELF(TM.Options.UseInitArray);
72 }
73 
74 void
75 X86FuchsiaTargetObjectFile::Initialize(MCContext &Ctx,
76  const TargetMachine &TM) {
78  InitializeELF(TM.Options.UseInitArray);
79 }
80 
81 void
82 X86LinuxNaClTargetObjectFile::Initialize(MCContext &Ctx,
83  const TargetMachine &TM) {
85  InitializeELF(TM.Options.UseInitArray);
86 }
87 
88 void X86SolarisTargetObjectFile::Initialize(MCContext &Ctx,
89  const TargetMachine &TM) {
91  InitializeELF(TM.Options.UseInitArray);
92 }
static const MCSymbolRefExpr * create(const MCSymbol *Symbol, MCContext &Ctx)
Definition: MCExpr.h:321
This class represents lattice values for constants.
Definition: AllocatorList.h:23
This represents an "assembler immediate".
Definition: MCValue.h:39
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
MCSymbol * getCFIPersonalitySymbol(const GlobalValue *GV, const TargetMachine &TM, MachineModuleInfo *MMI) const override
const MCExpr * getTTypeGlobalReference(const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM, MachineModuleInfo *MMI, MCStreamer &Streamer) const override
The mach-o version of this method defaults to returning a stub reference.
int64_t getConstant() const
Definition: MCValue.h:46
const MCExpr * getDebugThreadLocalSymbol(const MCSymbol *Sym) const override
Describe a TLS variable address within debug info.
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:35
Context object for machine code objects.
Definition: MCContext.h:62
static const MCBinaryExpr * createAdd(const MCExpr *LHS, const MCExpr *RHS, MCContext &Ctx)
Definition: MCExpr.h:459
Streaming machine code generation interface.
Definition: MCStreamer.h:188
MCSymbol * getSymbol(const GlobalValue *GV) const
const MCExpr * getTTypeGlobalReference(const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM, MachineModuleInfo *MMI, MCStreamer &Streamer) const override
The mach-o version of this method defaults to returning a stub reference.
unsigned UseInitArray
UseInitArray - Use .init_array instead of .ctors for static constructors.
This file contains constants used for implementing Dwarf debug support.
TargetOptions Options
const MCExpr * getIndirectSymViaGOTPCRel(const MCSymbol *Sym, const MCValue &MV, int64_t Offset, MachineModuleInfo *MMI, MCStreamer &Streamer) const override
Get MachO PC relative GOT entry relocation.
Primary interface to the complete machine description for the target machine.
Definition: TargetMachine.h:65
void Initialize(MCContext &Ctx, const TargetMachine &TM) override
This method must be called before any actual lowering is done.
static const MCConstantExpr * create(int64_t Value, MCContext &Ctx)
Definition: MCExpr.cpp:163
This class contains meta information specific to a module.
This file describes how to lower LLVM code to machine code.