Imported Upstream version 5.18.0.246

Former-commit-id: 0c7ce5b1a7851e13f22acfd379b7f9fb304e4833

external/llvm/lib/Target/X86/X86TargetObjectFile.cpp

@@ -0,0 +1,190 @@
+//===-- X86TargetObjectFile.cpp - X86 Object Info -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "X86TargetObjectFile.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/BinaryFormat/COFF.h"
+#include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/CodeGen/TargetLowering.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/IR/Operator.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSectionCOFF.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCValue.h"
+
+using namespace llvm;
+using namespace dwarf;
+
+const MCExpr *X86_64MachoTargetObjectFile::getTTypeGlobalReference(
+    const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM,
+    MachineModuleInfo *MMI, MCStreamer &Streamer) const {
+
+  // On Darwin/X86-64, we can reference dwarf symbols with foo@GOTPCREL+4, which
+  // is an indirect pc-relative reference.
+  if ((Encoding & DW_EH_PE_indirect) && (Encoding & DW_EH_PE_pcrel)) {
+    const MCSymbol *Sym = TM.getSymbol(GV);
+    const MCExpr *Res =
+      MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
+    const MCExpr *Four = MCConstantExpr::create(4, getContext());
+    return MCBinaryExpr::createAdd(Res, Four, getContext());
+  }
+
+  return TargetLoweringObjectFileMachO::getTTypeGlobalReference(
+      GV, Encoding, TM, MMI, Streamer);
+}
+
+MCSymbol *X86_64MachoTargetObjectFile::getCFIPersonalitySymbol(
+    const GlobalValue *GV, const TargetMachine &TM,
+    MachineModuleInfo *MMI) const {
+  return TM.getSymbol(GV);
+}
+
+const MCExpr *X86_64MachoTargetObjectFile::getIndirectSymViaGOTPCRel(
+    const MCSymbol *Sym, const MCValue &MV, int64_t Offset,
+    MachineModuleInfo *MMI, MCStreamer &Streamer) const {
+  // On Darwin/X86-64, we need to use foo@GOTPCREL+4 to access the got entry
+  // from a data section. In case there's an additional offset, then use
+  // foo@GOTPCREL+4+<offset>.
+  unsigned FinalOff = Offset+MV.getConstant()+4;
+  const MCExpr *Res =
+    MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_GOTPCREL, getContext());
+  const MCExpr *Off = MCConstantExpr::create(FinalOff, getContext());
+  return MCBinaryExpr::createAdd(Res, Off, getContext());
+}
+
+const MCExpr *X86ELFTargetObjectFile::getDebugThreadLocalSymbol(
+    const MCSymbol *Sym) const {
+  return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_DTPOFF, getContext());
+}
+
+void
+X86FreeBSDTargetObjectFile::Initialize(MCContext &Ctx,
+                                       const TargetMachine &TM) {
+  TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+  InitializeELF(TM.Options.UseInitArray);
+}
+
+void
+X86FuchsiaTargetObjectFile::Initialize(MCContext &Ctx,
+                                       const TargetMachine &TM) {
+  TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+  InitializeELF(TM.Options.UseInitArray);
+}
+
+void
+X86LinuxNaClTargetObjectFile::Initialize(MCContext &Ctx,
+                                         const TargetMachine &TM) {
+  TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+  InitializeELF(TM.Options.UseInitArray);
+}
+
+void X86SolarisTargetObjectFile::Initialize(MCContext &Ctx,
+                                            const TargetMachine &TM) {
+  TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+  InitializeELF(TM.Options.UseInitArray);
+}
+
+const MCExpr *X86WindowsTargetObjectFile::lowerRelativeReference(
+    const GlobalValue *LHS, const GlobalValue *RHS,
+    const TargetMachine &TM) const {
+  // Our symbols should exist in address space zero, cowardly no-op if
+  // otherwise.
+  if (LHS->getType()->getPointerAddressSpace() != 0 ||
+      RHS->getType()->getPointerAddressSpace() != 0)
+    return nullptr;
+
+  // Both ptrtoint instructions must wrap global objects:
+  // - Only global variables are eligible for image relative relocations.
+  // - The subtrahend refers to the special symbol __ImageBase, a GlobalVariable.
+  // We expect __ImageBase to be a global variable without a section, externally
+  // defined.
+  //
+  // It should look something like this: @__ImageBase = external constant i8
+  if (!isa<GlobalObject>(LHS) || !isa<GlobalVariable>(RHS) ||
+      LHS->isThreadLocal() || RHS->isThreadLocal() ||
+      RHS->getName() != "__ImageBase" || !RHS->hasExternalLinkage() ||
+      cast<GlobalVariable>(RHS)->hasInitializer() || RHS->hasSection())
+    return nullptr;
+
+  return MCSymbolRefExpr::create(TM.getSymbol(LHS),
+                                 MCSymbolRefExpr::VK_COFF_IMGREL32,
+                                 getContext());
+}
+
+static std::string APIntToHexString(const APInt &AI) {
+  unsigned Width = (AI.getBitWidth() / 8) * 2;
+  std::string HexString = utohexstr(AI.getLimitedValue(), /*LowerCase=*/true);
+  unsigned Size = HexString.size();
+  assert(Width >= Size && "hex string is too large!");
+  HexString.insert(HexString.begin(), Width - Size, '0');
+
+  return HexString;
+}
+
+static std::string scalarConstantToHexString(const Constant *C) {
+  Type *Ty = C->getType();
+  if (isa<UndefValue>(C)) {
+    return APIntToHexString(APInt::getNullValue(Ty->getPrimitiveSizeInBits()));
+  } else if (const auto *CFP = dyn_cast<ConstantFP>(C)) {
+    return APIntToHexString(CFP->getValueAPF().bitcastToAPInt());
+  } else if (const auto *CI = dyn_cast<ConstantInt>(C)) {
+    return APIntToHexString(CI->getValue());
+  } else {
+    unsigned NumElements;
+    if (isa<VectorType>(Ty))
+      NumElements = Ty->getVectorNumElements();
+    else
+      NumElements = Ty->getArrayNumElements();
+    std::string HexString;
+    for (int I = NumElements - 1, E = -1; I != E; --I)
+      HexString += scalarConstantToHexString(C->getAggregateElement(I));
+    return HexString;
+  }
+}
+
+MCSection *X86WindowsTargetObjectFile::getSectionForConstant(
+    const DataLayout &DL, SectionKind Kind, const Constant *C,
+    unsigned &Align) const {
+  if (Kind.isMergeableConst() && C) {
+    const unsigned Characteristics = COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+                                     COFF::IMAGE_SCN_MEM_READ |
+                                     COFF::IMAGE_SCN_LNK_COMDAT;
+    std::string COMDATSymName;
+    if (Kind.isMergeableConst4()) {
+      if (Align <= 4) {
+        COMDATSymName = "__real@" + scalarConstantToHexString(C);
+        Align = 4;
+      }
+    } else if (Kind.isMergeableConst8()) {
+      if (Align <= 8) {
+        COMDATSymName = "__real@" + scalarConstantToHexString(C);
+        Align = 8;
+      }
+    } else if (Kind.isMergeableConst16()) {
+      if (Align <= 16) {
+        COMDATSymName = "__xmm@" + scalarConstantToHexString(C);
+        Align = 16;
+      }
+    } else if (Kind.isMergeableConst32()) {
+      if (Align <= 32) {
+        COMDATSymName = "__ymm@" + scalarConstantToHexString(C);
+        Align = 32;
+      }
+    }
+
+    if (!COMDATSymName.empty())
+      return getContext().getCOFFSection(".rdata", Characteristics, Kind,
+                                         COMDATSymName,
+                                         COFF::IMAGE_COMDAT_SELECT_ANY);
+  }
+
+  return TargetLoweringObjectFile::getSectionForConstant(DL, Kind, C, Align);
+}