xref: /freebsd/contrib/llvm-project/llvm/lib/Target/X86/X86TargetObjectFile.cpp (revision 770cf0a5f02dc8983a89c6568d741fbc25baa999)
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 "MCTargetDesc/X86MCAsmInfo.h"
11 #include "llvm/BinaryFormat/Dwarf.h"
12 #include "llvm/MC/MCExpr.h"
13 #include "llvm/MC/MCValue.h"
14 #include "llvm/Target/TargetMachine.h"
15 
16 using namespace llvm;
17 using namespace dwarf;
18 
19 const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference(
20     const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM,
21     MachineModuleInfo *MMI, MCStreamer &Streamer) const {
22 
23   // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
24   // is an indirect pc-relative reference.
25   if ((Encoding & DW_EH_PE_indirect) && (Encoding & DW_EH_PE_pcrel)) {
26     const MCSymbol *Sym = TM.getSymbol(GV);
27     const MCExpr *Res =
28         MCSymbolRefExpr::create(Sym, X86::S_GOTPCREL, getContext());
29     const MCExpr *Four = MCConstantExpr::create(4, getContext());
30     return MCBinaryExpr::createAdd(Res, Four, getContext());
31   }
32 
33   return TargetLoweringObjectFileMachO::getTTypeGlobalReference(
34       GV, Encoding, TM, MMI, Streamer);
35 }
36 
37 MCSymbol *X86_64MachoTargetObjectFile::getCFIPersonalitySymbol(
38     const GlobalValue *GV, const TargetMachine &TM,
39     MachineModuleInfo *MMI) const {
40   return TM.getSymbol(GV);
41 }
42 
43 const MCExpr *X86_64MachoTargetObjectFile::getIndirectSymViaGOTPCRel(
44     const GlobalValue *GV, const MCSymbol *Sym, const MCValue &MV,
45     int64_t Offset, MachineModuleInfo *MMI, MCStreamer &Streamer) const {
46   // On Darwin/X86-64, we need to use foo@GOTPCREL+4 to access the got entry
47   // from a data section. In case there's an additional offset, then use
48   // foo@GOTPCREL+4+<offset>.
49   unsigned FinalOff = Offset+MV.getConstant()+4;
50   const MCExpr *Res =
51       MCSymbolRefExpr::create(Sym, X86::S_GOTPCREL, getContext());
52   const MCExpr *Off = MCConstantExpr::create(FinalOff, getContext());
53   return MCBinaryExpr::createAdd(Res, Off, getContext());
54 }
55 
56 X86ELFTargetObjectFile::X86ELFTargetObjectFile() {
57   PLTRelativeSpecifier = X86::S_PLT;
58 }
59 
60 const MCExpr *X86ELFTargetObjectFile::getDebugThreadLocalSymbol(
61     const MCSymbol *Sym) const {
62   return MCSymbolRefExpr::create(Sym, X86::S_DTPOFF, getContext());
63 }
64 
65 const MCExpr *X86_64ELFTargetObjectFile::getIndirectSymViaGOTPCRel(
66     const GlobalValue *GV, const MCSymbol *Sym, const MCValue &MV,
67     int64_t Offset, MachineModuleInfo *MMI, MCStreamer &Streamer) const {
68   int64_t FinalOffset = Offset + MV.getConstant();
69   const MCExpr *Res =
70       MCSymbolRefExpr::create(Sym, X86::S_GOTPCREL, getContext());
71   const MCExpr *Off = MCConstantExpr::create(FinalOffset, getContext());
72   return MCBinaryExpr::createAdd(Res, Off, getContext());
73 }
74