blob: f8bcd616e111780528368429cf1a6147146d82ae [file] [log] [blame]
Jia Liub22310f2012-02-18 12:03:15 +00001//===-- X86TargetObjectFile.cpp - X86 Object Info -------------------------===//
Chris Lattnerb8666022009-09-16 01:46:41 +00002//
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
Anton Korobeynikovae4ccc12010-02-15 22:35:59 +000010#include "X86TargetObjectFile.h"
David Majnemer8bce66b2014-07-14 22:57:27 +000011#include "llvm/ADT/StringExtras.h"
Chandler Carruth07baed52014-01-13 08:04:33 +000012#include "llvm/IR/Mangler.h"
David Majnemerdee10572014-01-15 09:16:42 +000013#include "llvm/IR/Operator.h"
Chris Lattner3a78ce32009-09-18 20:22:52 +000014#include "llvm/MC/MCContext.h"
Daniel Dunbar55992562010-03-15 23:51:06 +000015#include "llvm/MC/MCExpr.h"
David Majnemer8bce66b2014-07-14 22:57:27 +000016#include "llvm/MC/MCSectionCOFF.h"
Rafael Espindolaca3e0ee2012-06-19 00:48:28 +000017#include "llvm/MC/MCSectionELF.h"
Anton Korobeynikovae4ccc12010-02-15 22:35:59 +000018#include "llvm/Support/Dwarf.h"
Rafael Espindoladaeafb42014-02-19 17:23:20 +000019#include "llvm/Target/TargetLowering.h"
Jakub Staszakab3d8782013-01-10 23:43:56 +000020
Chris Lattnerb8666022009-09-16 01:46:41 +000021using namespace llvm;
Anton Korobeynikovae4ccc12010-02-15 22:35:59 +000022using namespace dwarf;
Chris Lattnerb8666022009-09-16 01:46:41 +000023
Rafael Espindola15b26692014-02-09 14:50:44 +000024const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference(
25 const GlobalValue *GV, unsigned Encoding, Mangler &Mang,
Rafael Espindoladaeafb42014-02-19 17:23:20 +000026 const TargetMachine &TM, MachineModuleInfo *MMI,
27 MCStreamer &Streamer) const {
Anton Korobeynikovae4ccc12010-02-15 22:35:59 +000028
Chris Lattnerb8666022009-09-16 01:46:41 +000029 // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
30 // is an indirect pc-relative reference.
Joerg Sonnenbergerfe543642014-04-30 22:40:27 +000031 if ((Encoding & DW_EH_PE_indirect) && (Encoding & DW_EH_PE_pcrel)) {
Rafael Espindolaa3ad4e62014-02-19 20:30:41 +000032 const MCSymbol *Sym = TM.getSymbol(GV, Mang);
Anton Korobeynikovc9adb6a2010-02-15 22:38:10 +000033 const MCExpr *Res =
Daniel Dunbar55992562010-03-15 23:51:06 +000034 MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
Anton Korobeynikovc9adb6a2010-02-15 22:38:10 +000035 const MCExpr *Four = MCConstantExpr::Create(4, getContext());
36 return MCBinaryExpr::CreateAdd(Res, Four, getContext());
Anton Korobeynikovae4ccc12010-02-15 22:35:59 +000037 }
38
Rafael Espindola15b26692014-02-09 14:50:44 +000039 return TargetLoweringObjectFileMachO::getTTypeGlobalReference(
Rafael Espindoladaeafb42014-02-19 17:23:20 +000040 GV, Encoding, Mang, TM, MMI, Streamer);
Chris Lattnerb8666022009-09-16 01:46:41 +000041}
42
Rafael Espindoladaeafb42014-02-19 17:23:20 +000043MCSymbol *X86_64MachoTargetObjectFile::getCFIPersonalitySymbol(
44 const GlobalValue *GV, Mangler &Mang, const TargetMachine &TM,
45 MachineModuleInfo *MMI) const {
Rafael Espindolaa3ad4e62014-02-19 20:30:41 +000046 return TM.getSymbol(GV, Mang);
Rafael Espindola08704342011-04-27 23:08:15 +000047}
Rafael Espindolaca3e0ee2012-06-19 00:48:28 +000048
49void
50X86LinuxTargetObjectFile::Initialize(MCContext &Ctx, const TargetMachine &TM) {
51 TargetLoweringObjectFileELF::Initialize(Ctx, TM);
52 InitializeELF(TM.Options.UseInitArray);
53}
David Blaikie1b01ae82013-07-01 21:45:25 +000054
Ulrich Weigand2b6fc8d2013-07-02 18:47:09 +000055const MCExpr *
David Blaikie1b01ae82013-07-01 21:45:25 +000056X86LinuxTargetObjectFile::getDebugThreadLocalSymbol(
57 const MCSymbol *Sym) const {
58 return MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext());
59}
David Majnemerdee10572014-01-15 09:16:42 +000060
Rafael Espindoladaeafb42014-02-19 17:23:20 +000061const MCExpr *X86WindowsTargetObjectFile::getExecutableRelativeSymbol(
62 const ConstantExpr *CE, Mangler &Mang, const TargetMachine &TM) const {
David Majnemerdee10572014-01-15 09:16:42 +000063 // We are looking for the difference of two symbols, need a subtraction
64 // operation.
65 const SubOperator *Sub = dyn_cast<SubOperator>(CE);
66 if (!Sub)
Craig Topper062a2ba2014-04-25 05:30:21 +000067 return nullptr;
David Majnemerdee10572014-01-15 09:16:42 +000068
69 // Symbols must first be numbers before we can subtract them, we need to see a
70 // ptrtoint on both subtraction operands.
71 const PtrToIntOperator *SubLHS =
72 dyn_cast<PtrToIntOperator>(Sub->getOperand(0));
73 const PtrToIntOperator *SubRHS =
74 dyn_cast<PtrToIntOperator>(Sub->getOperand(1));
75 if (!SubLHS || !SubRHS)
Craig Topper062a2ba2014-04-25 05:30:21 +000076 return nullptr;
David Majnemerdee10572014-01-15 09:16:42 +000077
78 // Our symbols should exist in address space zero, cowardly no-op if
79 // otherwise.
80 if (SubLHS->getPointerAddressSpace() != 0 ||
81 SubRHS->getPointerAddressSpace() != 0)
Craig Topper062a2ba2014-04-25 05:30:21 +000082 return nullptr;
David Majnemerdee10572014-01-15 09:16:42 +000083
84 // Both ptrtoint instructions must wrap global variables:
85 // - Only global variables are eligible for image relative relocations.
86 // - The subtrahend refers to the special symbol __ImageBase, a global.
87 const GlobalVariable *GVLHS =
88 dyn_cast<GlobalVariable>(SubLHS->getPointerOperand());
89 const GlobalVariable *GVRHS =
90 dyn_cast<GlobalVariable>(SubRHS->getPointerOperand());
91 if (!GVLHS || !GVRHS)
Craig Topper062a2ba2014-04-25 05:30:21 +000092 return nullptr;
David Majnemerdee10572014-01-15 09:16:42 +000093
94 // We expect __ImageBase to be a global variable without a section, externally
95 // defined.
96 //
97 // It should look something like this: @__ImageBase = external constant i8
98 if (GVRHS->isThreadLocal() || GVRHS->getName() != "__ImageBase" ||
99 !GVRHS->hasExternalLinkage() || GVRHS->hasInitializer() ||
100 GVRHS->hasSection())
Craig Topper062a2ba2014-04-25 05:30:21 +0000101 return nullptr;
David Majnemerdee10572014-01-15 09:16:42 +0000102
103 // An image-relative, thread-local, symbol makes no sense.
104 if (GVLHS->isThreadLocal())
Craig Topper062a2ba2014-04-25 05:30:21 +0000105 return nullptr;
David Majnemerdee10572014-01-15 09:16:42 +0000106
Rafael Espindolaa3ad4e62014-02-19 20:30:41 +0000107 return MCSymbolRefExpr::Create(TM.getSymbol(GVLHS, Mang),
Rafael Espindoladaeafb42014-02-19 17:23:20 +0000108 MCSymbolRefExpr::VK_COFF_IMGREL32,
109 getContext());
David Majnemerdee10572014-01-15 09:16:42 +0000110}
David Majnemer8bce66b2014-07-14 22:57:27 +0000111
David Majnemer4e3ccc02014-07-15 02:34:12 +0000112static std::string APIntToHexString(const APInt &AI) {
113 unsigned Width = (AI.getBitWidth() / 8) * 2;
David Majnemer8bce66b2014-07-14 22:57:27 +0000114 std::string HexString = utohexstr(AI.getLimitedValue(), /*LowerCase=*/true);
115 unsigned Size = HexString.size();
116 assert(Width >= Size && "hex string is too large!");
117 HexString.insert(HexString.begin(), Width - Size, '0');
118
119 return HexString;
120}
121
122
123static std::string scalarConstantToHexString(const Constant *C) {
124 Type *Ty = C->getType();
David Majnemer4e3ccc02014-07-15 02:34:12 +0000125 APInt AI;
126 if (isa<UndefValue>(C)) {
127 AI = APInt(Ty->getPrimitiveSizeInBits(), /*val=*/0);
128 } else if (Ty->isFloatTy() || Ty->isDoubleTy()) {
David Majnemer8bce66b2014-07-14 22:57:27 +0000129 const auto *CFP = cast<ConstantFP>(C);
David Majnemer4e3ccc02014-07-15 02:34:12 +0000130 AI = CFP->getValueAPF().bitcastToAPInt();
131 } else if (Ty->isIntegerTy()) {
David Majnemer8bce66b2014-07-14 22:57:27 +0000132 const auto *CI = cast<ConstantInt>(C);
David Majnemer4e3ccc02014-07-15 02:34:12 +0000133 AI = CI->getValue();
134 } else {
135 llvm_unreachable("unexpected constant pool element type!");
David Majnemer8bce66b2014-07-14 22:57:27 +0000136 }
David Majnemer4e3ccc02014-07-15 02:34:12 +0000137 return APIntToHexString(AI);
David Majnemer8bce66b2014-07-14 22:57:27 +0000138}
139
140const MCSection *
141X86WindowsTargetObjectFile::getSectionForConstant(SectionKind Kind,
142 const Constant *C) const {
143 if (Kind.isReadOnly()) {
144 if (C) {
145 Type *Ty = C->getType();
146 SmallString<32> COMDATSymName;
147 if (Ty->isFloatTy() || Ty->isDoubleTy()) {
148 COMDATSymName = "__real@";
149 COMDATSymName += scalarConstantToHexString(C);
150 } else if (const auto *VTy = dyn_cast<VectorType>(Ty)) {
151 uint64_t NumBits = VTy->getBitWidth();
152 if (NumBits == 128 || NumBits == 256) {
David Majnemer8bce66b2014-07-14 22:57:27 +0000153 COMDATSymName = NumBits == 128 ? "__xmm@" : "__ymm@";
David Majnemer3821ff02014-07-15 23:01:10 +0000154 for (int I = VTy->getNumElements() - 1, E = -1; I != E; --I)
155 COMDATSymName +=
156 scalarConstantToHexString(C->getAggregateElement(I));
David Majnemer8bce66b2014-07-14 22:57:27 +0000157 }
158 }
159 if (!COMDATSymName.empty()) {
160 unsigned Characteristics = COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
161 COFF::IMAGE_SCN_MEM_READ |
162 COFF::IMAGE_SCN_LNK_COMDAT;
163 return getContext().getCOFFSection(".rdata", Characteristics, Kind,
164 COMDATSymName,
165 COFF::IMAGE_COMDAT_SELECT_ANY);
166 }
167 }
168 }
169
170 return TargetLoweringObjectFile::getSectionForConstant(Kind, C);
171}