C++ ArrayRef::size方法代码示例

//
// runTargetDesc - Output the target register and register file descriptions.
//
void
RegisterInfoEmitter::runTargetDesc(raw_ostream &OS, CodeGenTarget &Target,
                                   CodeGenRegBank &RegBank){
  EmitSourceFileHeader("Target Register and Register Classes Information", OS);

  OS << "\n#ifdef GET_REGINFO_TARGET_DESC\n";
  OS << "#undef GET_REGINFO_TARGET_DESC\n";

  OS << "namespace llvm {\n\n";

  // Get access to MCRegisterClass data.
  OS << "extern const MCRegisterClass " << Target.getName()
     << "MCRegisterClasses[];\n";

  // Start out by emitting each of the register classes.
  ArrayRef<CodeGenRegisterClass*> RegisterClasses = RegBank.getRegClasses();

  // Collect all registers belonging to any allocatable class.
  std::set<Record*> AllocatableRegs;

  // Collect allocatable registers.
  for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
    const CodeGenRegisterClass &RC = *RegisterClasses[rc];
    ArrayRef<Record*> Order = RC.getOrder();

    if (RC.Allocatable)
      AllocatableRegs.insert(Order.begin(), Order.end());
  }

  // Build a shared array of value types.
  SequenceToOffsetTable<std::vector<MVT::SimpleValueType> > VTSeqs;
  for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc)
    VTSeqs.add(RegisterClasses[rc]->VTs);
  VTSeqs.layout();
  OS << "\nstatic const MVT::SimpleValueType VTLists[] = {\n";
  VTSeqs.emit(OS, printSimpleValueType, "MVT::Other");
  OS << "};\n";

  // Now that all of the structs have been emitted, emit the instances.
  if (!RegisterClasses.empty()) {
    std::map<unsigned, std::set<unsigned> > SuperRegClassMap;

    OS << "\nstatic const TargetRegisterClass *const "
       << "NullRegClasses[] = { NULL };\n\n";

    unsigned NumSubRegIndices = RegBank.getSubRegIndices().size();

    if (NumSubRegIndices) {
      // Compute the super-register classes for each RegisterClass
      for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
        const CodeGenRegisterClass &RC = *RegisterClasses[rc];
        for (DenseMap<Record*,Record*>::const_iterator
             i = RC.SubRegClasses.begin(),
             e = RC.SubRegClasses.end(); i != e; ++i) {
          // Find the register class number of i->second for SuperRegClassMap.
          const CodeGenRegisterClass *RC2 = RegBank.getRegClass(i->second);
          assert(RC2 && "Invalid register class in SubRegClasses");
          SuperRegClassMap[RC2->EnumValue].insert(rc);
        }
      }

      // Emit the super-register classes for each RegisterClass
      for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
        const CodeGenRegisterClass &RC = *RegisterClasses[rc];

        // Give the register class a legal C name if it's anonymous.
        std::string Name = RC.getName();

        OS << "// " << Name
           << " Super-register Classes...\n"
           << "static const TargetRegisterClass *const "
           << Name << "SuperRegClasses[] = {\n  ";

        bool Empty = true;
        std::map<unsigned, std::set<unsigned> >::iterator I =
          SuperRegClassMap.find(rc);
        if (I != SuperRegClassMap.end()) {
          for (std::set<unsigned>::iterator II = I->second.begin(),
                 EE = I->second.end(); II != EE; ++II) {
            const CodeGenRegisterClass &RC2 = *RegisterClasses[*II];
            if (!Empty)
              OS << ", ";
            OS << "&" << RC2.getQualifiedName() << "RegClass";
            Empty = false;
          }
        }

        OS << (!Empty ? ", " : "") << "NULL";
        OS << "\n};\n\n";
      }
    }

    // Emit the sub-classes array for each RegisterClass
    for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
      const CodeGenRegisterClass &RC = *RegisterClasses[rc];

      // Give the register class a legal C name if it's anonymous.
//.........这里部分代码省略.........

void llvm::printCOFFUnwindInfo(const COFFObjectFile *Obj) {
  const coff_file_header *Header;
  if (error(Obj->getHeader(Header))) return;

  if (Header->Machine != COFF::IMAGE_FILE_MACHINE_AMD64) {
    errs() << "Unsupported image machine type "
              "(currently only AMD64 is supported).\n";
    return;
  }

  const coff_section *Pdata = 0;

  error_code ec;
  for (section_iterator SI = Obj->begin_sections(),
                        SE = Obj->end_sections();
                        SI != SE; SI.increment(ec)) {
    if (error(ec)) return;

    StringRef Name;
    if (error(SI->getName(Name))) continue;

    if (Name != ".pdata") continue;

    Pdata = Obj->getCOFFSection(SI);
    std::vector<RelocationRef> Rels;
    for (relocation_iterator RI = SI->begin_relocations(),
                             RE = SI->end_relocations();
                             RI != RE; RI.increment(ec)) {
      if (error(ec)) break;
      Rels.push_back(*RI);
    }

    // Sort relocations by address.
    std::sort(Rels.begin(), Rels.end(), RelocAddressLess);

    ArrayRef<uint8_t> Contents;
    if (error(Obj->getSectionContents(Pdata, Contents))) continue;
    if (Contents.empty()) continue;

    ArrayRef<RuntimeFunction> RFs(
                  reinterpret_cast<const RuntimeFunction *>(Contents.data()),
                                  Contents.size() / sizeof(RuntimeFunction));
    for (const RuntimeFunction *I = RFs.begin(), *E = RFs.end(); I < E; ++I) {
      const uint64_t SectionOffset = std::distance(RFs.begin(), I)
                                     * sizeof(RuntimeFunction);

      outs() << "Function Table:\n";

      outs() << "  Start Address: ";
      printCOFFSymbolAddress(outs(), Rels, SectionOffset +
                             /*offsetof(RuntimeFunction, StartAddress)*/ 0,
                             I->StartAddress);
      outs() << "\n";

      outs() << "  End Address: ";
      printCOFFSymbolAddress(outs(), Rels, SectionOffset +
                             /*offsetof(RuntimeFunction, EndAddress)*/ 4,
                             I->EndAddress);
      outs() << "\n";

      outs() << "  Unwind Info Address: ";
      printCOFFSymbolAddress(outs(), Rels, SectionOffset +
                             /*offsetof(RuntimeFunction, UnwindInfoOffset)*/ 8,
                             I->UnwindInfoOffset);
      outs() << "\n";

      ArrayRef<uint8_t> XContents;
      uint64_t UnwindInfoOffset = 0;
      if (error(getSectionContents(Obj, Rels, SectionOffset +
                              /*offsetof(RuntimeFunction, UnwindInfoOffset)*/ 8,
                                   XContents, UnwindInfoOffset))) continue;
      if (XContents.empty()) continue;

      UnwindInfoOffset += I->UnwindInfoOffset;
      if (UnwindInfoOffset > XContents.size()) continue;

      const Win64EH::UnwindInfo *UI =
                            reinterpret_cast<const Win64EH::UnwindInfo *>
                              (XContents.data() + UnwindInfoOffset);

      // The casts to int are required in order to output the value as number.
      // Without the casts the value would be interpreted as char data (which
      // results in garbage output).
      outs() << "  Version: " << static_cast<int>(UI->getVersion()) << "\n";
      outs() << "  Flags: " << static_cast<int>(UI->getFlags());
      if (UI->getFlags()) {
          if (UI->getFlags() & UNW_ExceptionHandler)
            outs() << " UNW_ExceptionHandler";
          if (UI->getFlags() & UNW_TerminateHandler)
            outs() << " UNW_TerminateHandler";
          if (UI->getFlags() & UNW_ChainInfo)
            outs() << " UNW_ChainInfo";
      }
      outs() << "\n";
      outs() << "  Size of prolog: "
             << static_cast<int>(UI->PrologSize) << "\n";
      outs() << "  Number of Codes: "
             << static_cast<int>(UI->NumCodes) << "\n";
      // Maybe this should move to output of UOP_SetFPReg?
      if (UI->getFrameRegister()) {
//.........这里部分代码省略.........

/// Force liveness of registers.
void RegPressureTracker::addLiveRegs(ArrayRef<unsigned> Regs) {
  for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
    if (LiveRegs.insert(Regs[i]))
      increaseRegPressure(Regs[i]);
  }
}

ArrayRef<Ref<DataBlock> >
DataBlock::getDataBlocks(ArrayRef<unsigned char> rawCodewords,
                         Version *version,
                         ErrorCorrectionLevel &ecLevel) {

    // Figure out the number and size of data blocks used by this version and
    // error correction level
    Version::ECBlocks &ecBlocks = version->getECBlocksForLevel(ecLevel);

    // First count the total number of data blocks
    int totalBlocks = 0;
    vector<Version::ECB*> ecBlockArray = ecBlocks.getECBlocks();
    for (size_t i = 0; i < ecBlockArray.size(); i++) {
        totalBlocks += ecBlockArray[i]->getCount();
    }

    // Now establish DataBlocks of the appropriate size and number of data codewords
    ArrayRef<Ref<DataBlock> > result(totalBlocks);
    int numResultBlocks = 0;
    for (size_t j = 0; j < ecBlockArray.size(); j++) {
        Version::ECB *ecBlock = ecBlockArray[j];
        for (int i = 0; i < ecBlock->getCount(); i++) {
            int numDataCodewords = ecBlock->getDataCodewords();
            int numBlockCodewords = ecBlocks.getECCodewords() + numDataCodewords;
            ArrayRef<unsigned char> buffer(numBlockCodewords);
            Ref<DataBlock> blockRef(new DataBlock(numDataCodewords, buffer));
            result[numResultBlocks++] = blockRef;
        }
    }

    // All blocks have the same amount of data, except that the last n
    // (where n may be 0) have 1 more byte. Figure out where these start.
    int shorterBlocksTotalCodewords = result[0]->codewords_.size();
    int longerBlocksStartAt = result->size() - 1;
    while (longerBlocksStartAt >= 0) {
        int numCodewords = result[longerBlocksStartAt]->codewords_.size();
        if (numCodewords == shorterBlocksTotalCodewords) {
            break;
        }
        if (numCodewords != shorterBlocksTotalCodewords + 1) {
            throw IllegalArgumentException("Data block sizes differ by more than 1");
        }
        longerBlocksStartAt--;
    }
    longerBlocksStartAt++;

    int shorterBlocksNumDataCodewords = shorterBlocksTotalCodewords - ecBlocks.getECCodewords();
    // The last elements of result may be 1 element longer;
    // first fill out as many elements as all of them have
    int rawCodewordsOffset = 0;
    for (int i = 0; i < shorterBlocksNumDataCodewords; i++) {
        for (int j = 0; j < numResultBlocks; j++) {
            result[j]->codewords_[i] = rawCodewords[rawCodewordsOffset++];
        }
    }
    // Fill out the last data block in the longer ones
    for (int j = longerBlocksStartAt; j < numResultBlocks; j++) {
        result[j]->codewords_[shorterBlocksNumDataCodewords] = rawCodewords[rawCodewordsOffset++];
    }
    // Now add in error correction blocks
    int max = result[0]->codewords_.size();
    for (int i = shorterBlocksNumDataCodewords; i < max; i++) {
        for (int j = 0; j < numResultBlocks; j++) {
            int iOffset = j < longerBlocksStartAt ? i : i + 1;
            result[j]->codewords_[iOffset] = rawCodewords[rawCodewordsOffset++];
        }
    }

    if ((size_t) rawCodewordsOffset != rawCodewords.size()) {
        throw IllegalArgumentException("rawCodewordsOffset != rawCodewords.length");
    }

    return result;
}

SolutionDiff::SolutionDiff(ArrayRef<Solution> solutions) {
  if (solutions.size() <= 1)
    return;

  // Populate the type bindings with the first solution.
  llvm::DenseMap<TypeVariableType *, SmallVector<Type, 2>> typeBindings;
  for (auto binding : solutions[0].typeBindings) {
    typeBindings[binding.first].push_back(binding.second);
  }

  // Populate the overload choices with the first solution.
  llvm::DenseMap<ConstraintLocator *, SmallVector<OverloadChoice, 2>>
    overloadChoices;
  for (auto choice : solutions[0].overloadChoices) {
    overloadChoices[choice.first].push_back(choice.second.choice);
  }

  // Find the type variables and overload locators common to all of the
  // solutions.
  for (auto &solution : solutions.slice(1)) {
    // For each type variable bound in all of the previous solutions, check
    // whether we have a binding for this type variable in this solution.
    SmallVector<TypeVariableType *, 4> removeTypeBindings;
    for (auto &binding : typeBindings) {
      auto known = solution.typeBindings.find(binding.first);
      if (known == solution.typeBindings.end()) {
        removeTypeBindings.push_back(binding.first);
        continue;
      }

      // Add this solution's binding to the results.
      binding.second.push_back(known->second);
    }

    // Remove those type variables for which this solution did not have a
    // binding.
    for (auto typeVar : removeTypeBindings) {
      typeBindings.erase(typeVar);
    }
    removeTypeBindings.clear();

    // For each overload locator for which we have an overload choice in
    // all of the previous solutions. Check whether we have an overload choice
    // in this solution.
    SmallVector<ConstraintLocator *, 4> removeOverloadChoices;
    for (auto &overloadChoice : overloadChoices) {
      auto known = solution.overloadChoices.find(overloadChoice.first);
      if (known == solution.overloadChoices.end()) {
        removeOverloadChoices.push_back(overloadChoice.first);
        continue;
      }

      // Add this solution's overload choice to the results.
      overloadChoice.second.push_back(known->second.choice);
    }

    // Remove those overload locators for which this solution did not have
    // an overload choice.
    for (auto overloadChoice : removeOverloadChoices) {
      overloadChoices.erase(overloadChoice);
    }
  }

  // Look through the type variables that have bindings in all of the
  // solutions, and add those that have differences to the diff.
  for (auto &binding : typeBindings) {
    Type singleType;
    for (auto type : binding.second) {
      if (!singleType)
        singleType = type;
      else if (!singleType->isEqual(type)) {
        // We have a difference. Add this binding to the diff.
        this->typeBindings.push_back(
          SolutionDiff::TypeBindingDiff{
            binding.first,
            std::move(binding.second)
          });

        break;
      }
    }
  }

  // Look through the overload locators that have overload choices in all of
  // the solutions, and add those that have differences to the diff.
  for (auto &overloadChoice : overloadChoices) {
    OverloadChoice singleChoice = overloadChoice.second[0];
    for (auto choice : overloadChoice.second) {
      if (!sameOverloadChoice(singleChoice, choice)) {
        // We have a difference. Add this set of overload choices to the diff.
        this->overloads.push_back(
          SolutionDiff::OverloadDiff{
            overloadChoice.first,
            overloadChoice.second
          });
        
      }
    }
  }
}

void APValue::printPretty(raw_ostream &Out, ASTContext &Ctx, QualType Ty) const{
  switch (getKind()) {
  case APValue::Uninitialized:
    Out << "<uninitialized>";
    return;
  case APValue::Int:
    if (Ty->isBooleanType())
      Out << (getInt().getBoolValue() ? "true" : "false");
    else
      Out << getInt();
    return;
  case APValue::Float:
    Out << GetApproxValue(getFloat());
    return;
  case APValue::Vector: {
    Out << '{';
    QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
    getVectorElt(0).printPretty(Out, Ctx, ElemTy);
    for (unsigned i = 1; i != getVectorLength(); ++i) {
      Out << ", ";
      getVectorElt(i).printPretty(Out, Ctx, ElemTy);
    }
    Out << '}';
    return;
  }
  case APValue::ComplexInt:
    Out << getComplexIntReal() << "+" << getComplexIntImag() << "i";
    return;
  case APValue::ComplexFloat:
    Out << GetApproxValue(getComplexFloatReal()) << "+"
        << GetApproxValue(getComplexFloatImag()) << "i";
    return;
  case APValue::LValue: {
    LValueBase Base = getLValueBase();
    if (!Base) {
      Out << "0";
      return;
    }

    bool IsReference = Ty->isReferenceType();
    QualType InnerTy
      = IsReference ? Ty.getNonReferenceType() : Ty->getPointeeType();

    if (!hasLValuePath()) {
      // No lvalue path: just print the offset.
      CharUnits O = getLValueOffset();
      CharUnits S = Ctx.getTypeSizeInChars(InnerTy);
      if (!O.isZero()) {
        if (IsReference)
          Out << "*(";
        if (O % S) {
          Out << "(char*)";
          S = CharUnits::One();
        }
        Out << '&';
      } else if (!IsReference)
        Out << '&';

      if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>())
        Out << *VD;
      else
        Base.get<const Expr*>()->printPretty(Out, 0, Ctx.getPrintingPolicy());
      if (!O.isZero()) {
        Out << " + " << (O / S);
        if (IsReference)
          Out << ')';
      }
      return;
    }

    // We have an lvalue path. Print it out nicely.
    if (!IsReference)
      Out << '&';
    else if (isLValueOnePastTheEnd())
      Out << "*(&";

    QualType ElemTy;
    if (const ValueDecl *VD = Base.dyn_cast<const ValueDecl*>()) {
      Out << *VD;
      ElemTy = VD->getType();
    } else {
      const Expr *E = Base.get<const Expr*>();
      E->printPretty(Out, 0, Ctx.getPrintingPolicy());
      ElemTy = E->getType();
    }

    ArrayRef<LValuePathEntry> Path = getLValuePath();
    const CXXRecordDecl *CastToBase = 0;
    for (unsigned I = 0, N = Path.size(); I != N; ++I) {
      if (ElemTy->getAs<RecordType>()) {
        // The lvalue refers to a class type, so the next path entry is a base
        // or member.
        const Decl *BaseOrMember =
        BaseOrMemberType::getFromOpaqueValue(Path[I].BaseOrMember).getPointer();
        if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(BaseOrMember)) {
          CastToBase = RD;
          ElemTy = Ctx.getRecordType(RD);
        } else {
          const ValueDecl *VD = cast<ValueDecl>(BaseOrMember);
          Out << ".";
//.........这里部分代码省略.........

/// This function goes through the arguments of F and sees if we have anything
/// to optimize in which case it returns true. If we have nothing to optimize,
/// it returns false.
bool FunctionAnalyzer::analyze() {
  // For now ignore functions with indirect results.
  if (F->getLoweredFunctionType()->hasIndirectResult())
    return false;

  ArrayRef<SILArgument *> Args = F->begin()->getBBArgs();

  // A map from consumed SILArguments to the release associated with an
  // argument.
  ConsumedArgToEpilogueReleaseMatcher ArgToReturnReleaseMap(RCIA, F);
  ConsumedArgToEpilogueReleaseMatcher ArgToThrowReleaseMap(
      RCIA, F, ConsumedArgToEpilogueReleaseMatcher::ExitKind::Throw);

  for (unsigned i = 0, e = Args.size(); i != e; ++i) {
    ArgumentDescriptor A(Allocator, Args[i]);
    bool HaveOptimizedArg = false;

    bool isABIRequired = isArgumentABIRequired(Args[i]);
    auto OnlyRelease = getNonTrivialNonDebugReleaseUse(Args[i]);

    // If this argument is not ABI required and has not uses except for debug
    // instructions, remove it.
    if (!isABIRequired && OnlyRelease && OnlyRelease.getValue().isNull()) {
      A.IsDead = true;
      HaveOptimizedArg = true;
      ++NumDeadArgsEliminated;
    }

    // See if we can find a ref count equivalent strong_release or release_value
    // at the end of this function if our argument is an @owned parameter.
    if (A.hasConvention(ParameterConvention::Direct_Owned)) {
      if (auto *Release = ArgToReturnReleaseMap.releaseForArgument(A.Arg)) {
        SILInstruction *ReleaseInThrow = nullptr;

        // If the function has a throw block we must also find a matching
        // release in the throw block.
        if (!ArgToThrowReleaseMap.hasBlock() ||
            (ReleaseInThrow = ArgToThrowReleaseMap.releaseForArgument(A.Arg))) {

          // TODO: accept a second release in the throw block to let the
          // argument be dead.
          if (OnlyRelease && OnlyRelease.getValue().getPtrOrNull() == Release) {
            A.IsDead = true;
          }
          A.CalleeRelease = Release;
          A.CalleeReleaseInThrowBlock = ReleaseInThrow;
          HaveOptimizedArg = true;
          ++NumOwnedConvertedToGuaranteed;
        }
      }
    }

    if (A.shouldExplode()) {
      HaveOptimizedArg = true;
      ++NumSROAArguments;
    }

    if (HaveOptimizedArg) {
      ShouldOptimize = true;
      // Store that we have modified the self argument. We need to change the
      // calling convention later.
      if (Args[i]->isSelf())
        HaveModifiedSelfArgument = true;
    }

    // Add the argument to our list.
    ArgDescList.push_back(std::move(A));
  }

  return ShouldOptimize;
}

ManagedValue SILGenFunction::emitExistentialErasure(
                            SILLocation loc,
                            CanType concreteFormalType,
                            const TypeLowering &concreteTL,
                            const TypeLowering &existentialTL,
                            ArrayRef<ProtocolConformanceRef> conformances,
                            SGFContext C,
                            llvm::function_ref<ManagedValue (SGFContext)> F,
                            bool allowEmbeddedNSError) {
  // Mark the needed conformances as used.
  for (auto conformance : conformances)
    SGM.useConformance(conformance);

  // If we're erasing to the 'Error' type, we might be able to get an NSError
  // representation more efficiently.
  auto &ctx = getASTContext();
  if (ctx.LangOpts.EnableObjCInterop && conformances.size() == 1 &&
      conformances[0].getRequirement() == ctx.getErrorDecl() &&
      ctx.getNSErrorDecl()) {
    auto nsErrorDecl = ctx.getNSErrorDecl();

    // If the concrete type is NSError or a subclass thereof, just erase it
    // directly.
    auto nsErrorType = nsErrorDecl->getDeclaredType()->getCanonicalType();
    if (nsErrorType->isExactSuperclassOf(concreteFormalType, nullptr)) {
      ManagedValue nsError =  F(SGFContext());
      if (nsErrorType != concreteFormalType) {
        nsError = ManagedValue(B.createUpcast(loc, nsError.getValue(),
                                              getLoweredType(nsErrorType)),
                               nsError.getCleanup());
      }
      return emitBridgedToNativeError(loc, nsError);
    }

    // If the concrete type is known to conform to _BridgedStoredNSError,
    // call the _nsError witness getter to extract the NSError directly,
    // then just erase the NSError.
    if (auto storedNSErrorConformance =
          SGM.getConformanceToBridgedStoredNSError(loc, concreteFormalType)) {
      auto nsErrorVar = SGM.getNSErrorRequirement(loc);
      if (!nsErrorVar) return emitUndef(loc, existentialTL.getLoweredType());

      ArrayRef<Substitution> nsErrorVarSubstitutions;

      // Devirtualize.  Maybe this should be done implicitly by
      // emitPropertyLValue?
      if (storedNSErrorConformance->isConcrete()) {
        if (auto witnessVar = storedNSErrorConformance->getConcrete()
                                          ->getWitness(nsErrorVar, nullptr)) {
          nsErrorVar = cast<VarDecl>(witnessVar.getDecl());
          nsErrorVarSubstitutions = witnessVar.getSubstitutions();
        }
      }

      auto nativeError = F(SGFContext());

      WritebackScope writebackScope(*this);
      auto nsError =
        emitRValueForPropertyLoad(loc, nativeError, concreteFormalType,
                                  /*super*/ false, nsErrorVar,
                                  nsErrorVarSubstitutions,
                                  AccessSemantics::Ordinary, nsErrorType,
                                  SGFContext())
        .getAsSingleValue(*this, loc);

      return emitBridgedToNativeError(loc, nsError);
    }

    // Otherwise, if it's an archetype, try calling the _getEmbeddedNSError()
    // witness to try to dig out the embedded NSError.  But don't do this
    // when we're being called recursively.
    if (isa<ArchetypeType>(concreteFormalType) && allowEmbeddedNSError) {
      auto contBB = createBasicBlock();
      auto isNotPresentBB = createBasicBlock();
      auto isPresentBB = createBasicBlock();

      // Call swift_stdlib_getErrorEmbeddedNSError to attempt to extract an
      // NSError from the value.
      auto getEmbeddedNSErrorFn = SGM.getGetErrorEmbeddedNSError(loc);
      if (!getEmbeddedNSErrorFn)
        return emitUndef(loc, existentialTL.getLoweredType());

      Substitution getEmbeddedNSErrorSubstitutions[1] = {
        Substitution(concreteFormalType, conformances)
      };

      ManagedValue concreteValue = F(SGFContext());
      ManagedValue potentialNSError =
        emitApplyOfLibraryIntrinsic(loc,
                                    getEmbeddedNSErrorFn,
                                    getEmbeddedNSErrorSubstitutions,
                                    { concreteValue.copy(*this, loc) },
                                    SGFContext())
          .getAsSingleValue(*this, loc);

      // We're going to consume 'concreteValue' in exactly one branch,
      // so kill its cleanup now and recreate it on both branches.
      (void) concreteValue.forward(*this);

      // Check whether we got an NSError back.
//.........这里部分代码省略.........

/// AggregateAvailableValues - Given a bunch of primitive subelement values,
/// build out the right aggregate type (LoadTy) by emitting tuple and struct
/// instructions as necessary.
static SILValue
AggregateAvailableValues(SILInstruction *Inst, SILType LoadTy,
                         SILValue Address,
                         ArrayRef<std::pair<SILValue, unsigned>> AvailableValues,
                         unsigned FirstElt) {
  assert(LoadTy.isObject());
  SILModule &M = Inst->getModule();
  
  // Check to see if the requested value is fully available, as an aggregate.
  // This is a super-common case for single-element structs, but is also a
  // general answer for arbitrary structs and tuples as well.
  if (FirstElt < AvailableValues.size()) {  // #Elements may be zero.
    SILValue FirstVal = AvailableValues[FirstElt].first;
    if (FirstVal && AvailableValues[FirstElt].second == 0 &&
        FirstVal->getType() == LoadTy) {
      // If the first element of this value is available, check any extra ones
      // before declaring success.
      bool AllMatch = true;
      for (unsigned i = 0, e = getNumSubElements(LoadTy, M); i != e; ++i)
        if (AvailableValues[FirstElt+i].first != FirstVal ||
            AvailableValues[FirstElt+i].second != i) {
          AllMatch = false;
          break;
        }
      
      if (AllMatch)
        return FirstVal;
    }
  }
  
  
  SILBuilderWithScope B(Inst);
  
  if (TupleType *TT = LoadTy.getAs<TupleType>()) {
    SmallVector<SILValue, 4> ResultElts;
    
    for (unsigned EltNo : indices(TT->getElements())) {
      SILType EltTy = LoadTy.getTupleElementType(EltNo);
      unsigned NumSubElt = getNumSubElements(EltTy, M);
      
      // If we are missing any of the available values in this struct element,
      // compute an address to load from.
      SILValue EltAddr;
      if (anyMissing(FirstElt, NumSubElt, AvailableValues))
        EltAddr = B.createTupleElementAddr(Inst->getLoc(), Address, EltNo,
                                           EltTy.getAddressType());
      
      ResultElts.push_back(AggregateAvailableValues(Inst, EltTy, EltAddr,
                                                    AvailableValues, FirstElt));
      FirstElt += NumSubElt;
    }
    
    return B.createTuple(Inst->getLoc(), LoadTy, ResultElts);
  }
  
  // Extract struct elements from fully referenceable structs.
  if (auto *SD = getFullyReferenceableStruct(LoadTy)) {
    SmallVector<SILValue, 4> ResultElts;
    
    for (auto *FD : SD->getStoredProperties()) {
      SILType EltTy = LoadTy.getFieldType(FD, M);
      unsigned NumSubElt = getNumSubElements(EltTy, M);
      
      // If we are missing any of the available values in this struct element,
      // compute an address to load from.
      SILValue EltAddr;
      if (anyMissing(FirstElt, NumSubElt, AvailableValues))
        EltAddr = B.createStructElementAddr(Inst->getLoc(), Address, FD,
                                            EltTy.getAddressType());
      
      ResultElts.push_back(AggregateAvailableValues(Inst, EltTy, EltAddr,
                                                    AvailableValues, FirstElt));
      FirstElt += NumSubElt;
    }
    return B.createStruct(Inst->getLoc(), LoadTy, ResultElts);
  }
  
  // Otherwise, we have a simple primitive.  If the value is available, use it,
  // otherwise emit a load of the value.
  auto Val = AvailableValues[FirstElt];
  if (!Val.first)
    return B.createLoad(Inst->getLoc(), Address);
  
  SILValue EltVal = ExtractSubElement(Val.first, Val.second, B, Inst->getLoc());
  // It must be the same type as LoadTy if available.
  assert(EltVal->getType() == LoadTy &&
         "Subelement types mismatch");
  return EltVal;
}

/// Return true if we can evaluate the specified expression tree if the vector
/// elements were shuffled in a different order.
static bool CanEvaluateShuffled(Value *V, ArrayRef<int> Mask,
                                unsigned Depth = 5) {
  // We can always reorder the elements of a constant.
  if (isa<Constant>(V))
    return true;

  // We won't reorder vector arguments. No IPO here.
  Instruction *I = dyn_cast<Instruction>(V);
  if (!I) return false;

  // Two users may expect different orders of the elements. Don't try it.
  if (!I->hasOneUse())
    return false;

  if (Depth == 0) return false;

  switch (I->getOpcode()) {
    case Instruction::Add:
    case Instruction::FAdd:
    case Instruction::Sub:
    case Instruction::FSub:
    case Instruction::Mul:
    case Instruction::FMul:
    case Instruction::UDiv:
    case Instruction::SDiv:
    case Instruction::FDiv:
    case Instruction::URem:
    case Instruction::SRem:
    case Instruction::FRem:
    case Instruction::Shl:
    case Instruction::LShr:
    case Instruction::AShr:
    case Instruction::And:
    case Instruction::Or:
    case Instruction::Xor:
    case Instruction::ICmp:
    case Instruction::FCmp:
    case Instruction::Trunc:
    case Instruction::ZExt:
    case Instruction::SExt:
    case Instruction::FPToUI:
    case Instruction::FPToSI:
    case Instruction::UIToFP:
    case Instruction::SIToFP:
    case Instruction::FPTrunc:
    case Instruction::FPExt:
    case Instruction::GetElementPtr: {
      for (Value *Operand : I->operands()) {
        if (!CanEvaluateShuffled(Operand, Mask, Depth-1))
          return false;
      }
      return true;
    }
    case Instruction::InsertElement: {
      ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(2));
      if (!CI) return false;
      int ElementNumber = CI->getLimitedValue();

      // Verify that 'CI' does not occur twice in Mask. A single 'insertelement'
      // can't put an element into multiple indices.
      bool SeenOnce = false;
      for (int i = 0, e = Mask.size(); i != e; ++i) {
        if (Mask[i] == ElementNumber) {
          if (SeenOnce)
            return false;
          SeenOnce = true;
        }
      }
      return CanEvaluateShuffled(I->getOperand(0), Mask, Depth-1);
    }
  }
  return false;
}

bool LiveRangeCalc::findReachingDefs(LiveRange &LR, MachineBasicBlock &UseMBB,
                                     SlotIndex Use, unsigned PhysReg,
                                     ArrayRef<SlotIndex> Undefs) {
  unsigned UseMBBNum = UseMBB.getNumber();

  // Block numbers where LR should be live-in.
  SmallVector<unsigned, 16> WorkList(1, UseMBBNum);

  // Remember if we have seen more than one value.
  bool UniqueVNI = true;
  VNInfo *TheVNI = nullptr;

  bool FoundUndef = false;

  // Using Seen as a visited set, perform a BFS for all reaching defs.
  for (unsigned i = 0; i != WorkList.size(); ++i) {
    MachineBasicBlock *MBB = MF->getBlockNumbered(WorkList[i]);

#ifndef NDEBUG
    if (Undefs.size() > 0 && MBB->pred_empty()) {
      MBB->getParent()->verify();
      errs() << "Use of " << PrintReg(PhysReg)
             << " does not have a corresponding definition on every path:\n";
      const MachineInstr *MI = Indexes->getInstructionFromIndex(Use);
      if (MI != nullptr)
        errs() << Use << " " << *MI;
      llvm_unreachable("Use not jointly dominated by defs.");
    }

    if (TargetRegisterInfo::isPhysicalRegister(PhysReg) &&
        !MBB->isLiveIn(PhysReg)) {
      MBB->getParent()->verify();
      const TargetRegisterInfo *TRI = MRI->getTargetRegisterInfo();
      errs() << "The register " << PrintReg(PhysReg, TRI)
             << " needs to be live in to BB#" << MBB->getNumber()
             << ", but is missing from the live-in list.\n";
      llvm_unreachable("Invalid global physical register");
    }
#endif
    FoundUndef |= MBB->pred_empty();

    for (MachineBasicBlock::pred_iterator PI = MBB->pred_begin(),
         PE = MBB->pred_end(); PI != PE; ++PI) {
       MachineBasicBlock *Pred = *PI;

       // Is this a known live-out block?
       if (Seen.test(Pred->getNumber())) {
         if (VNInfo *VNI = Map[Pred].first) {
           if (TheVNI && TheVNI != VNI)
             UniqueVNI = false;
           TheVNI = VNI;
         }
         continue;
       }

       SlotIndex Start, End;
       std::tie(Start, End) = Indexes->getMBBRange(Pred);

       // First time we see Pred.  Try to determine the live-out value, but set
       // it as null if Pred is live-through with an unknown value.
       auto EP = LR.extendInBlock(Undefs, Start, End);
       VNInfo *VNI = EP.first;
       FoundUndef |= EP.second;
       setLiveOutValue(Pred, VNI);
       if (VNI) {
         if (TheVNI && TheVNI != VNI)
           UniqueVNI = false;
         TheVNI = VNI;
       }
       if (VNI || EP.second)
         continue;

       // No, we need a live-in value for Pred as well
       if (Pred != &UseMBB)
         WorkList.push_back(Pred->getNumber());
       else
          // Loopback to UseMBB, so value is really live through.
         Use = SlotIndex();
    }
  }

  LiveIn.clear();
  FoundUndef |= (TheVNI == nullptr);
  if (Undefs.size() > 0 && FoundUndef)
    UniqueVNI = false;

  // Both updateSSA() and LiveRangeUpdater benefit from ordered blocks, but
  // neither require it. Skip the sorting overhead for small updates.
  if (WorkList.size() > 4)
    array_pod_sort(WorkList.begin(), WorkList.end());

  // If a unique reaching def was found, blit in the live ranges immediately.
  if (UniqueVNI) {
    assert(TheVNI != nullptr);
    LiveRangeUpdater Updater(&LR);
    for (unsigned BN : WorkList) {
      SlotIndex Start, End;
      std::tie(Start, End) = Indexes->getMBBRange(BN);
      // Trim the live range in UseMBB.
      if (BN == UseMBBNum && Use.isValid())
//.........这里部分代码省略.........

void NonNullParamChecker::checkPreCall(const CallEvent &Call,
                                       CheckerContext &C) const {
  const Decl *FD = Call.getDecl();
  if (!FD)
    return;

  // Merge all non-null attributes
  unsigned NumArgs = Call.getNumArgs();
  llvm::SmallBitVector AttrNonNull(NumArgs);
  for (const auto *NonNull : FD->specific_attrs<NonNullAttr>()) {
    if (!NonNull->args_size()) {
      AttrNonNull.set(0, NumArgs);
      break;
    }
    for (unsigned Val : NonNull->args()) {
      if (Val >= NumArgs)
        continue;
      AttrNonNull.set(Val);
    }
  }

  ProgramStateRef state = C.getState();

  CallEvent::param_type_iterator TyI = Call.param_type_begin(),
                                 TyE = Call.param_type_end();

  for (unsigned idx = 0; idx < NumArgs; ++idx) {

    // Check if the parameter is a reference. We want to report when reference
    // to a null pointer is passed as a paramter.
    bool haveRefTypeParam = false;
    if (TyI != TyE) {
      haveRefTypeParam = (*TyI)->isReferenceType();
      TyI++;
    }

    bool haveAttrNonNull = AttrNonNull[idx];
    if (!haveAttrNonNull) {
      // Check if the parameter is also marked 'nonnull'.
      ArrayRef<ParmVarDecl*> parms = Call.parameters();
      if (idx < parms.size())
        haveAttrNonNull = parms[idx]->hasAttr<NonNullAttr>();
    }

    if (!haveRefTypeParam && !haveAttrNonNull)
      continue;

    // If the value is unknown or undefined, we can't perform this check.
    const Expr *ArgE = Call.getArgExpr(idx);
    SVal V = Call.getArgSVal(idx);
    Optional<DefinedSVal> DV = V.getAs<DefinedSVal>();
    if (!DV)
      continue;

    // Process the case when the argument is not a location.
    assert(!haveRefTypeParam || DV->getAs<Loc>());

    if (haveAttrNonNull && !DV->getAs<Loc>()) {
      // If the argument is a union type, we want to handle a potential
      // transparent_union GCC extension.
      if (!ArgE)
        continue;

      QualType T = ArgE->getType();
      const RecordType *UT = T->getAsUnionType();
      if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
        continue;

      if (Optional<nonloc::CompoundVal> CSV =
              DV->getAs<nonloc::CompoundVal>()) {
        nonloc::CompoundVal::iterator CSV_I = CSV->begin();
        assert(CSV_I != CSV->end());
        V = *CSV_I;
        DV = V.getAs<DefinedSVal>();
        assert(++CSV_I == CSV->end());
        // FIXME: Handle (some_union){ some_other_union_val }, which turns into
        // a LazyCompoundVal inside a CompoundVal.
        if (!V.getAs<Loc>())
          continue;
        // Retrieve the corresponding expression.
        if (const CompoundLiteralExpr *CE = dyn_cast<CompoundLiteralExpr>(ArgE))
          if (const InitListExpr *IE =
                dyn_cast<InitListExpr>(CE->getInitializer()))
             ArgE = dyn_cast<Expr>(*(IE->begin()));

      } else {
        // FIXME: Handle LazyCompoundVals?
        continue;
      }
    }

    ConstraintManager &CM = C.getConstraintManager();
    ProgramStateRef stateNotNull, stateNull;
    std::tie(stateNotNull, stateNull) = CM.assumeDual(state, *DV);

    if (stateNull) {
      if (!stateNotNull) {
        // Generate an error node.  Check for a null node in case
        // we cache out.
        if (ExplodedNode *errorNode = C.generateErrorNode(stateNull)) {
//.........这里部分代码省略.........

unsigned BasicTTI::getIntrinsicInstrCost(Intrinsic::ID IID, Type *RetTy,
                                         ArrayRef<Type *> Tys) const {
  unsigned ISD = 0;
  switch (IID) {
  default: {
    // Assume that we need to scalarize this intrinsic.
    unsigned ScalarizationCost = 0;
    unsigned ScalarCalls = 1;
    if (RetTy->isVectorTy()) {
      ScalarizationCost = getScalarizationOverhead(RetTy, true, false);
      ScalarCalls = std::max(ScalarCalls, RetTy->getVectorNumElements());
    }
    for (unsigned i = 0, ie = Tys.size(); i != ie; ++i) {
      if (Tys[i]->isVectorTy()) {
        ScalarizationCost += getScalarizationOverhead(Tys[i], false, true);
        ScalarCalls = std::max(ScalarCalls, RetTy->getVectorNumElements());
      }
    }

    return ScalarCalls + ScalarizationCost;
  }
  // Look for intrinsics that can be lowered directly or turned into a scalar
  // intrinsic call.
  case Intrinsic::sqrt:    ISD = ISD::FSQRT;  break;
  case Intrinsic::sin:     ISD = ISD::FSIN;   break;
  case Intrinsic::cos:     ISD = ISD::FCOS;   break;
  case Intrinsic::exp:     ISD = ISD::FEXP;   break;
  case Intrinsic::exp2:    ISD = ISD::FEXP2;  break;
  case Intrinsic::log:     ISD = ISD::FLOG;   break;
  case Intrinsic::log10:   ISD = ISD::FLOG10; break;
  case Intrinsic::log2:    ISD = ISD::FLOG2;  break;
  case Intrinsic::fabs:    ISD = ISD::FABS;   break;
  case Intrinsic::floor:   ISD = ISD::FFLOOR; break;
  case Intrinsic::ceil:    ISD = ISD::FCEIL;  break;
  case Intrinsic::trunc:   ISD = ISD::FTRUNC; break;
  case Intrinsic::rint:    ISD = ISD::FRINT;  break;
  case Intrinsic::pow:     ISD = ISD::FPOW;   break;
  case Intrinsic::fma:     ISD = ISD::FMA;    break;
  case Intrinsic::fmuladd: ISD = ISD::FMA;    break; // FIXME: mul + add?
  }

  std::pair<unsigned, MVT> LT = TLI->getTypeLegalizationCost(RetTy);

  if (TLI->isOperationLegalOrPromote(ISD, LT.second)) {
    // The operation is legal. Assume it costs 1.
    // If the type is split to multiple registers, assume that thre is some
    // overhead to this.
    // TODO: Once we have extract/insert subvector cost we need to use them.
    if (LT.first > 1)
      return LT.first * 2;
    return LT.first * 1;
  }

  if (!TLI->isOperationExpand(ISD, LT.second)) {
    // If the operation is custom lowered then assume
    // thare the code is twice as expensive.
    return LT.first * 2;
  }

  // Else, assume that we need to scalarize this intrinsic. For math builtins
  // this will emit a costly libcall, adding call overhead and spills. Make it
  // very expensive.
  if (RetTy->isVectorTy()) {
    unsigned Num = RetTy->getVectorNumElements();
    unsigned Cost = TopTTI->getIntrinsicInstrCost(IID, RetTy->getScalarType(),
                                                  Tys);
    return 10 * Cost * Num;
  }

  // This is going to be turned into a library call, make it expensive.
  return 10;
}

/// Produce note diagnostics for a jump into a protected scope.
void JumpScopeChecker::NoteJumpIntoScopes(ArrayRef<unsigned> ToScopes) {
  assert(!ToScopes.empty());
  for (unsigned I = 0, E = ToScopes.size(); I != E; ++I)
    if (Scopes[ToScopes[I]].InDiag)
      S.Diag(Scopes[ToScopes[I]].Loc, Scopes[ToScopes[I]].InDiag);
}

void elf::ObjectFile<ELFT>::initializeSections(
    DenseSet<CachedHashStringRef> &ComdatGroups) {
  const ELFFile<ELFT> &Obj = this->getObj();

  ArrayRef<Elf_Shdr> ObjSections =
      check(this->getObj().sections(), toString(this));
  uint64_t Size = ObjSections.size();
  this->Sections.resize(Size);
  this->SectionStringTable =
      check(Obj.getSectionStringTable(ObjSections), toString(this));

  for (size_t I = 0, E = ObjSections.size(); I < E; I++) {
    if (this->Sections[I] == &InputSection::Discarded)
      continue;
    const Elf_Shdr &Sec = ObjSections[I];

    // SHF_EXCLUDE'ed sections are discarded by the linker. However,
    // if -r is given, we'll let the final link discard such sections.
    // This is compatible with GNU.
    if ((Sec.sh_flags & SHF_EXCLUDE) && !Config->Relocatable) {
      this->Sections[I] = &InputSection::Discarded;
      continue;
    }

    switch (Sec.sh_type) {
    case SHT_GROUP: {
      // De-duplicate section groups by their signatures.
      StringRef Signature = getShtGroupSignature(ObjSections, Sec);
      bool IsNew = ComdatGroups.insert(CachedHashStringRef(Signature)).second;
      this->Sections[I] = &InputSection::Discarded;

      // If it is a new section group, we want to keep group members.
      // Group leader sections, which contain indices of group members, are
      // discarded because they are useless beyond this point. The only
      // exception is the -r option because in order to produce re-linkable
      // object files, we want to pass through basically everything.
      if (IsNew) {
        if (Config->Relocatable)
          this->Sections[I] = createInputSection(Sec);
        continue;
      }

      // Otherwise, discard group members.
      for (uint32_t SecIndex : getShtGroupEntries(Sec)) {
        if (SecIndex >= Size)
          fatal(toString(this) +
                ": invalid section index in group: " + Twine(SecIndex));
        this->Sections[SecIndex] = &InputSection::Discarded;
      }
      break;
    }
    case SHT_SYMTAB:
      this->initSymtab(ObjSections, &Sec);
      break;
    case SHT_SYMTAB_SHNDX:
      this->SymtabSHNDX =
          check(Obj.getSHNDXTable(Sec, ObjSections), toString(this));
      break;
    case SHT_STRTAB:
    case SHT_NULL:
      break;
    default:
      this->Sections[I] = createInputSection(Sec);
    }

    // .ARM.exidx sections have a reverse dependency on the InputSection they
    // have a SHF_LINK_ORDER dependency, this is identified by the sh_link.
    if (Sec.sh_flags & SHF_LINK_ORDER) {
      if (Sec.sh_link >= this->Sections.size())
        fatal(toString(this) + ": invalid sh_link index: " +
              Twine(Sec.sh_link));
      this->Sections[Sec.sh_link]->DependentSections.push_back(
          this->Sections[I]);
    }
  }
}