clang/lib/CodeGen/CGNonTrivialStruct.cpp

   1 //===--- CGNonTrivialStruct.cpp - Emit Special Functions for C Structs ----===//
   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 // This file defines functions to generate various special functions for C
  10 // structs.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "CodeGenFunction.h"
  15 #include "CodeGenModule.h"
  16 #include "clang/AST/NonTrivialTypeVisitor.h"
  17 #include "clang/CodeGen/CodeGenABITypes.h"
  18 #include "llvm/Support/ScopedPrinter.h"
  19 #include <array>
  20
  21 using namespace clang;
  22 using namespace CodeGen;
  23
  24 // Return the size of a field in number of bits.
  25 static uint64_t getFieldSize(const FieldDecl *FD, QualType FT,
  26                              ASTContext &Ctx) {
  27   if (FD && FD->isBitField())
  28     return FD->getBitWidthValue(Ctx);
  29   return Ctx.getTypeSize(FT);
  30 }
  31
  32 namespace {
  33 enum { DstIdx = 0, SrcIdx = 1 };
  34 const char *ValNameStr[2] = {"dst", "src"};
  35
  36 template <class Derived> struct StructVisitor {
  37   StructVisitor(ASTContext &Ctx) : Ctx(Ctx) {}
  38
  39   template <class... Ts>
  40   void visitStructFields(QualType QT, CharUnits CurStructOffset, Ts... Args) {
  41     const RecordDecl *RD = QT->castAs<RecordType>()->getDecl();
  42
  43     // Iterate over the fields of the struct.
  44     for (const FieldDecl *FD : RD->fields()) {
  45       QualType FT = FD->getType();
  46       FT = QT.isVolatileQualified() ? FT.withVolatile() : FT;
  47       asDerived().visit(FT, FD, CurStructOffset, Args...);
  48     }
  49
  50     asDerived().flushTrivialFields(Args...);
  51   }
  52
  53   template <class... Ts> void visitTrivial(Ts... Args) {}
  54
  55   template <class... Ts> void visitCXXDestructor(Ts... Args) {
  56     llvm_unreachable("field of a C++ struct type is not expected");
  57   }
  58
  59   template <class... Ts> void flushTrivialFields(Ts... Args) {}
  60
  61   uint64_t getFieldOffsetInBits(const FieldDecl *FD) {
  62     return FD ? Ctx.getASTRecordLayout(FD->getParent())
  63                     .getFieldOffset(FD->getFieldIndex())
  64               : 0;
  65   }
  66
  67   CharUnits getFieldOffset(const FieldDecl *FD) {
  68     return Ctx.toCharUnitsFromBits(getFieldOffsetInBits(FD));
  69   }
  70
  71   Derived &asDerived() { return static_cast<Derived &>(*this); }
  72
  73   ASTContext &getContext() { return Ctx; }
  74   ASTContext &Ctx;
  75 };
  76
  77 template <class Derived, bool IsMove>
  78 struct CopyStructVisitor : StructVisitor<Derived>,
  79                            CopiedTypeVisitor<Derived, IsMove> {
  80   using StructVisitor<Derived>::asDerived;
  81   using Super = CopiedTypeVisitor<Derived, IsMove>;
  82
  83   CopyStructVisitor(ASTContext &Ctx) : StructVisitor<Derived>(Ctx) {}
  84
  85   template <class... Ts>
  86   void preVisit(QualType::PrimitiveCopyKind PCK, QualType FT,
  87                 const FieldDecl *FD, CharUnits CurStructOffset, Ts &&... Args) {
  88     if (PCK)
  89       asDerived().flushTrivialFields(std::forward<Ts>(Args)...);
  90   }
  91
  92   template <class... Ts>
  93   void visitWithKind(QualType::PrimitiveCopyKind PCK, QualType FT,
  94                      const FieldDecl *FD, CharUnits CurStructOffset,
  95                      Ts &&... Args) {
  96     if (const auto *AT = asDerived().getContext().getAsArrayType(FT)) {
  97       asDerived().visitArray(PCK, AT, FT.isVolatileQualified(), FD,
  98                              CurStructOffset, std::forward<Ts>(Args)...);
  99       return;
 100     }
 101
 102     Super::visitWithKind(PCK, FT, FD, CurStructOffset,
 103                          std::forward<Ts>(Args)...);
 104   }
 105
 106   template <class... Ts>
 107   void visitTrivial(QualType FT, const FieldDecl *FD, CharUnits CurStructOffset,
 108                     Ts... Args) {
 109     assert(!FT.isVolatileQualified() && "volatile field not expected");
 110     ASTContext &Ctx = asDerived().getContext();
 111     uint64_t FieldSize = getFieldSize(FD, FT, Ctx);
 112
 113     // Ignore zero-sized fields.
 114     if (FieldSize == 0)
 115       return;
 116
 117     uint64_t FStartInBits = asDerived().getFieldOffsetInBits(FD);
 118     uint64_t FEndInBits = FStartInBits + FieldSize;
 119     uint64_t RoundedFEnd = llvm::alignTo(FEndInBits, Ctx.getCharWidth());
 120
 121     // Set Start if this is the first field of a sequence of trivial fields.
 122     if (Start == End)
 123       Start = CurStructOffset + Ctx.toCharUnitsFromBits(FStartInBits);
 124     End = CurStructOffset + Ctx.toCharUnitsFromBits(RoundedFEnd);
 125   }
 126
 127   CharUnits Start = CharUnits::Zero(), End = CharUnits::Zero();
 128 };
 129
 130 // This function creates the mangled name of a special function of a non-trivial
 131 // C struct. Since there is no ODR in C, the function is mangled based on the
 132 // struct contents and not the name. The mangled name has the following
 133 // structure:
 134 //
 135 // <function-name> ::= <prefix> <alignment-info> "_" <struct-field-info>
 136 // <prefix> ::= "__destructor_" | "__default_constructor_" |
 137 //              "__copy_constructor_" | "__move_constructor_" |
 138 //              "__copy_assignment_" | "__move_assignment_"
 139 // <alignment-info> ::= <dst-alignment> ["_" <src-alignment>]
 140 // <struct-field-info> ::= <field-info>+
 141 // <field-info> ::= <struct-or-scalar-field-info> | <array-field-info>
 142 // <struct-or-scalar-field-info> ::= "_S" <struct-field-info> |
 143 //                                   <strong-field-info> | <trivial-field-info>
 144 // <array-field-info> ::= "_AB" <array-offset> "s" <element-size> "n"
 145 //                        <num-elements> <innermost-element-info> "_AE"
 146 // <innermost-element-info> ::= <struct-or-scalar-field-info>
 147 // <strong-field-info> ::= "_s" ["b"] ["v"] <field-offset>
 148 // <trivial-field-info> ::= "_t" ["v"] <field-offset> "_" <field-size>
 149
 150 template <class Derived> struct GenFuncNameBase {
 151   std::string getVolatileOffsetStr(bool IsVolatile, CharUnits Offset) {
 152     std::string S;
 153     if (IsVolatile)
 154       S = "v";
 155     S += llvm::to_string(Offset.getQuantity());
 156     return S;
 157   }
 158
 159   void visitARCStrong(QualType FT, const FieldDecl *FD,
 160                       CharUnits CurStructOffset) {
 161     appendStr("_s");
 162     if (FT->isBlockPointerType())
 163       appendStr("b");
 164     CharUnits FieldOffset = CurStructOffset + asDerived().getFieldOffset(FD);
 165     appendStr(getVolatileOffsetStr(FT.isVolatileQualified(), FieldOffset));
 166   }
 167
 168   void visitARCWeak(QualType FT, const FieldDecl *FD,
 169                     CharUnits CurStructOffset) {
 170     appendStr("_w");
 171     CharUnits FieldOffset = CurStructOffset + asDerived().getFieldOffset(FD);
 172     appendStr(getVolatileOffsetStr(FT.isVolatileQualified(), FieldOffset));
 173   }
 174
 175   void visitStruct(QualType QT, const FieldDecl *FD,
 176                    CharUnits CurStructOffset) {
 177     CharUnits FieldOffset = CurStructOffset + asDerived().getFieldOffset(FD);
 178     appendStr("_S");
 179     asDerived().visitStructFields(QT, FieldOffset);
 180   }
 181
 182   template <class FieldKind>
 183   void visitArray(FieldKind FK, const ArrayType *AT, bool IsVolatile,
 184                   const FieldDecl *FD, CharUnits CurStructOffset) {
 185     // String for non-volatile trivial fields is emitted when
 186     // flushTrivialFields is called.
 187     if (!FK)
 188       return asDerived().visitTrivial(QualType(AT, 0), FD, CurStructOffset);
 189
 190     asDerived().flushTrivialFields();
 191     CharUnits FieldOffset = CurStructOffset + asDerived().getFieldOffset(FD);
 192     ASTContext &Ctx = asDerived().getContext();
 193     const ConstantArrayType *CAT = cast<ConstantArrayType>(AT);
 194     unsigned NumElts = Ctx.getConstantArrayElementCount(CAT);
 195     QualType EltTy = Ctx.getBaseElementType(CAT);
 196     CharUnits EltSize = Ctx.getTypeSizeInChars(EltTy);
 197     appendStr("_AB" + llvm::to_string(FieldOffset.getQuantity()) + "s" +
 198               llvm::to_string(EltSize.getQuantity()) + "n" +
 199               llvm::to_string(NumElts));
 200     EltTy = IsVolatile ? EltTy.withVolatile() : EltTy;
 201     asDerived().visitWithKind(FK, EltTy, nullptr, FieldOffset);
 202     appendStr("_AE");
 203   }
 204
 205   void appendStr(StringRef Str) { Name += Str; }
 206
 207   std::string getName(QualType QT, bool IsVolatile) {
 208     QT = IsVolatile ? QT.withVolatile() : QT;
 209     asDerived().visitStructFields(QT, CharUnits::Zero());
 210     return Name;
 211   }
 212
 213   Derived &asDerived() { return static_cast<Derived &>(*this); }
 214
 215   std::string Name;
 216 };
 217
 218 template <class Derived>
 219 struct GenUnaryFuncName : StructVisitor<Derived>, GenFuncNameBase<Derived> {
 220   GenUnaryFuncName(StringRef Prefix, CharUnits DstAlignment, ASTContext &Ctx)
 221       : StructVisitor<Derived>(Ctx) {
 222     this->appendStr(Prefix);
 223     this->appendStr(llvm::to_string(DstAlignment.getQuantity()));
 224   }
 225 };
 226
 227 // Helper function to create a null constant.
 228 static llvm::Constant *getNullForVariable(Address Addr) {
 229   llvm::Type *Ty = Addr.getElementType();
 230   return llvm::ConstantPointerNull::get(cast<llvm::PointerType>(Ty));
 231 }
 232
 233 template <bool IsMove>
 234 struct GenBinaryFuncName : CopyStructVisitor<GenBinaryFuncName<IsMove>, IsMove>,
 235                            GenFuncNameBase<GenBinaryFuncName<IsMove>> {
 236
 237   GenBinaryFuncName(StringRef Prefix, CharUnits DstAlignment,
 238                     CharUnits SrcAlignment, ASTContext &Ctx)
 239       : CopyStructVisitor<GenBinaryFuncName<IsMove>, IsMove>(Ctx) {
 240     this->appendStr(Prefix);
 241     this->appendStr(llvm::to_string(DstAlignment.getQuantity()));
 242     this->appendStr("_" + llvm::to_string(SrcAlignment.getQuantity()));
 243   }
 244
 245   void flushTrivialFields() {
 246     if (this->Start == this->End)
 247       return;
 248
 249     this->appendStr("_t" + llvm::to_string(this->Start.getQuantity()) + "w" +
 250                     llvm::to_string((this->End - this->Start).getQuantity()));
 251
 252     this->Start = this->End = CharUnits::Zero();
 253   }
 254
 255   void visitVolatileTrivial(QualType FT, const FieldDecl *FD,
 256                             CharUnits CurStructOffset) {
 257     // Zero-length bit-fields don't need to be copied/assigned.
 258     if (FD && FD->isZeroLengthBitField(this->Ctx))
 259       return;
 260
 261     // Because volatile fields can be bit-fields and are individually copied,
 262     // their offset and width are in bits.
 263     uint64_t OffsetInBits =
 264         this->Ctx.toBits(CurStructOffset) + this->getFieldOffsetInBits(FD);
 265     this->appendStr("_tv" + llvm::to_string(OffsetInBits) + "w" +
 266                     llvm::to_string(getFieldSize(FD, FT, this->Ctx)));
 267   }
 268 };
 269
 270 struct GenDefaultInitializeFuncName
 271     : GenUnaryFuncName<GenDefaultInitializeFuncName>,
 272       DefaultInitializedTypeVisitor<GenDefaultInitializeFuncName> {
 273   using Super = DefaultInitializedTypeVisitor<GenDefaultInitializeFuncName>;
 274   GenDefaultInitializeFuncName(CharUnits DstAlignment, ASTContext &Ctx)
 275       : GenUnaryFuncName<GenDefaultInitializeFuncName>("__default_constructor_",
 276                                                        DstAlignment, Ctx) {}
 277   void visitWithKind(QualType::PrimitiveDefaultInitializeKind PDIK, QualType FT,
 278                      const FieldDecl *FD, CharUnits CurStructOffset) {
 279     if (const auto *AT = getContext().getAsArrayType(FT)) {
 280       visitArray(PDIK, AT, FT.isVolatileQualified(), FD, CurStructOffset);
 281       return;
 282     }
 283
 284     Super::visitWithKind(PDIK, FT, FD, CurStructOffset);
 285   }
 286 };
 287
 288 struct GenDestructorFuncName : GenUnaryFuncName<GenDestructorFuncName>,
 289                                DestructedTypeVisitor<GenDestructorFuncName> {
 290   using Super = DestructedTypeVisitor<GenDestructorFuncName>;
 291   GenDestructorFuncName(const char *Prefix, CharUnits DstAlignment,
 292                         ASTContext &Ctx)
 293       : GenUnaryFuncName<GenDestructorFuncName>(Prefix, DstAlignment, Ctx) {}
 294   void visitWithKind(QualType::DestructionKind DK, QualType FT,
 295                      const FieldDecl *FD, CharUnits CurStructOffset) {
 296     if (const auto *AT = getContext().getAsArrayType(FT)) {
 297       visitArray(DK, AT, FT.isVolatileQualified(), FD, CurStructOffset);
 298       return;
 299     }
 300
 301     Super::visitWithKind(DK, FT, FD, CurStructOffset);
 302   }
 303 };
 304
 305 // Helper function that creates CGFunctionInfo for an N-ary special function.
 306 template <size_t N>
 307 static const CGFunctionInfo &getFunctionInfo(CodeGenModule &CGM,
 308                                              FunctionArgList &Args) {
 309   ASTContext &Ctx = CGM.getContext();
 310   llvm::SmallVector<ImplicitParamDecl *, N> Params;
 311   QualType ParamTy = Ctx.getPointerType(Ctx.VoidPtrTy);
 312
 313   for (unsigned I = 0; I < N; ++I)
 314     Params.push_back(ImplicitParamDecl::Create(
 315         Ctx, nullptr, SourceLocation(), &Ctx.Idents.get(ValNameStr[I]), ParamTy,
 316         ImplicitParamDecl::Other));
 317
 318   llvm::append_range(Args, Params);
 319
 320   return CGM.getTypes().arrangeBuiltinFunctionDeclaration(Ctx.VoidTy, Args);
 321 }
 322
 323 template <size_t N, size_t... Ints>
 324 static std::array<Address, N> getParamAddrs(std::index_sequence<Ints...> IntSeq,
 325                                             std::array<CharUnits, N> Alignments,
 326                                             const FunctionArgList &Args,
 327                                             CodeGenFunction *CGF) {
 328   return std::array<Address, N>{
 329       {Address(CGF->Builder.CreateLoad(CGF->GetAddrOfLocalVar(Args[Ints])),
 330                CGF->VoidPtrTy, Alignments[Ints], KnownNonNull)...}};
 331 }
 332
 333 // Template classes that are used as bases for classes that emit special
 334 // functions.
 335 template <class Derived> struct GenFuncBase {
 336   template <size_t N>
 337   void visitStruct(QualType FT, const FieldDecl *FD, CharUnits CurStructOffset,
 338                    std::array<Address, N> Addrs) {
 339     this->asDerived().callSpecialFunction(
 340         FT, CurStructOffset + asDerived().getFieldOffset(FD), Addrs);
 341   }
 342
 343   template <class FieldKind, size_t N>
 344   void visitArray(FieldKind FK, const ArrayType *AT, bool IsVolatile,
 345                   const FieldDecl *FD, CharUnits CurStructOffset,
 346                   std::array<Address, N> Addrs) {
 347     // Non-volatile trivial fields are copied when flushTrivialFields is called.
 348     if (!FK)
 349       return asDerived().visitTrivial(QualType(AT, 0), FD, CurStructOffset,
 350                                       Addrs);
 351
 352     asDerived().flushTrivialFields(Addrs);
 353     CodeGenFunction &CGF = *this->CGF;
 354     ASTContext &Ctx = CGF.getContext();
 355
 356     // Compute the end address.
 357     QualType BaseEltQT;
 358     std::array<Address, N> StartAddrs = Addrs;
 359     for (unsigned I = 0; I < N; ++I)
 360       StartAddrs[I] = getAddrWithOffset(Addrs[I], CurStructOffset, FD);
 361     Address DstAddr = StartAddrs[DstIdx];
 362     llvm::Value *NumElts = CGF.emitArrayLength(AT, BaseEltQT, DstAddr);
 363     unsigned BaseEltSize = Ctx.getTypeSizeInChars(BaseEltQT).getQuantity();
 364     llvm::Value *BaseEltSizeVal =
 365         llvm::ConstantInt::get(NumElts->getType(), BaseEltSize);
 366     llvm::Value *SizeInBytes =
 367         CGF.Builder.CreateNUWMul(BaseEltSizeVal, NumElts);
 368     llvm::Value *DstArrayEnd = CGF.Builder.CreateInBoundsGEP(
 369         CGF.Int8Ty, DstAddr.getPointer(), SizeInBytes);
 370     llvm::BasicBlock *PreheaderBB = CGF.Builder.GetInsertBlock();
 371
 372     // Create the header block and insert the phi instructions.
 373     llvm::BasicBlock *HeaderBB = CGF.createBasicBlock("loop.header");
 374     CGF.EmitBlock(HeaderBB);
 375     llvm::PHINode *PHIs[N];
 376
 377     for (unsigned I = 0; I < N; ++I) {
 378       PHIs[I] = CGF.Builder.CreatePHI(CGF.CGM.Int8PtrPtrTy, 2, "addr.cur");
 379       PHIs[I]->addIncoming(StartAddrs[I].getPointer(), PreheaderBB);
 380     }
 381
 382     // Create the exit and loop body blocks.
 383     llvm::BasicBlock *ExitBB = CGF.createBasicBlock("loop.exit");
 384     llvm::BasicBlock *LoopBB = CGF.createBasicBlock("loop.body");
 385
 386     // Emit the comparison and conditional branch instruction that jumps to
 387     // either the exit or the loop body.
 388     llvm::Value *Done =
 389         CGF.Builder.CreateICmpEQ(PHIs[DstIdx], DstArrayEnd, "done");
 390     CGF.Builder.CreateCondBr(Done, ExitBB, LoopBB);
 391
 392     // Visit the element of the array in the loop body.
 393     CGF.EmitBlock(LoopBB);
 394     QualType EltQT = AT->getElementType();
 395     CharUnits EltSize = Ctx.getTypeSizeInChars(EltQT);
 396     std::array<Address, N> NewAddrs = Addrs;
 397
 398     for (unsigned I = 0; I < N; ++I)
 399       NewAddrs[I] =
 400             Address(PHIs[I], CGF.Int8PtrTy,
 401                     StartAddrs[I].getAlignment().alignmentAtOffset(EltSize));
 402
 403     EltQT = IsVolatile ? EltQT.withVolatile() : EltQT;
 404     this->asDerived().visitWithKind(FK, EltQT, nullptr, CharUnits::Zero(),
 405                                     NewAddrs);
 406
 407     LoopBB = CGF.Builder.GetInsertBlock();
 408
 409     for (unsigned I = 0; I < N; ++I) {
 410       // Instrs to update the destination and source addresses.
 411       // Update phi instructions.
 412       NewAddrs[I] = getAddrWithOffset(NewAddrs[I], EltSize);
 413       PHIs[I]->addIncoming(NewAddrs[I].getPointer(), LoopBB);
 414     }
 415
 416     // Insert an unconditional branch to the header block.
 417     CGF.Builder.CreateBr(HeaderBB);
 418     CGF.EmitBlock(ExitBB);
 419   }
 420
 421   /// Return an address with the specified offset from the passed address.
 422   Address getAddrWithOffset(Address Addr, CharUnits Offset) {
 423     assert(Addr.isValid() && "invalid address");
 424     if (Offset.getQuantity() == 0)
 425       return Addr;
 426     Addr = Addr.withElementType(CGF->CGM.Int8Ty);
 427     Addr = CGF->Builder.CreateConstInBoundsGEP(Addr, Offset.getQuantity());
 428     return Addr.withElementType(CGF->CGM.Int8PtrTy);
 429   }
 430
 431   Address getAddrWithOffset(Address Addr, CharUnits StructFieldOffset,
 432                             const FieldDecl *FD) {
 433     return getAddrWithOffset(Addr, StructFieldOffset +
 434                                        asDerived().getFieldOffset(FD));
 435   }
 436
 437   template <size_t N>
 438   llvm::Function *getFunction(StringRef FuncName, QualType QT,
 439                               std::array<CharUnits, N> Alignments,
 440                               CodeGenModule &CGM) {
 441     // If the special function already exists in the module, return it.
 442     if (llvm::Function *F = CGM.getModule().getFunction(FuncName)) {
 443       bool WrongType = false;
 444       if (!F->getReturnType()->isVoidTy())
 445         WrongType = true;
 446       else {
 447         for (const llvm::Argument &Arg : F->args())
 448           if (Arg.getType() != CGM.Int8PtrPtrTy)
 449             WrongType = true;
 450       }
 451
 452       if (WrongType) {
 453         std::string FuncName = std::string(F->getName());
 454         SourceLocation Loc = QT->castAs<RecordType>()->getDecl()->getLocation();
 455         CGM.Error(Loc, "special function " + FuncName +
 456                            " for non-trivial C struct has incorrect type");
 457         return nullptr;
 458       }
 459       return F;
 460     }
 461
 462     ASTContext &Ctx = CGM.getContext();
 463     FunctionArgList Args;
 464     const CGFunctionInfo &FI = getFunctionInfo<N>(CGM, Args);
 465     llvm::FunctionType *FuncTy = CGM.getTypes().GetFunctionType(FI);
 466     llvm::Function *F =
 467         llvm::Function::Create(FuncTy, llvm::GlobalValue::LinkOnceODRLinkage,
 468                                FuncName, &CGM.getModule());
 469     F->setVisibility(llvm::GlobalValue::HiddenVisibility);
 470     CGM.SetLLVMFunctionAttributes(GlobalDecl(), FI, F, /*IsThunk=*/false);
 471     CGM.SetLLVMFunctionAttributesForDefinition(nullptr, F);
 472     CodeGenFunction NewCGF(CGM);
 473     setCGF(&NewCGF);
 474     CGF->StartFunction(GlobalDecl(), Ctx.VoidTy, F, FI, Args);
 475     auto AL = ApplyDebugLocation::CreateArtificial(*CGF);
 476     std::array<Address, N> Addrs =
 477         getParamAddrs<N>(std::make_index_sequence<N>{}, Alignments, Args, CGF);
 478     asDerived().visitStructFields(QT, CharUnits::Zero(), Addrs);
 479     CGF->FinishFunction();
 480     return F;
 481   }
 482
 483   template <size_t N>
 484   void callFunc(StringRef FuncName, QualType QT, std::array<Address, N> Addrs,
 485                 CodeGenFunction &CallerCGF) {
 486     std::array<CharUnits, N> Alignments;
 487     llvm::Value *Ptrs[N];
 488
 489     for (unsigned I = 0; I < N; ++I) {
 490       Alignments[I] = Addrs[I].getAlignment();
 491       Ptrs[I] = Addrs[I].getPointer();
 492     }
 493
 494     if (llvm::Function *F =
 495             getFunction(FuncName, QT, Alignments, CallerCGF.CGM))
 496       CallerCGF.EmitNounwindRuntimeCall(F, Ptrs);
 497   }
 498
 499   Derived &asDerived() { return static_cast<Derived &>(*this); }
 500
 501   void setCGF(CodeGenFunction *F) { CGF = F; }
 502
 503   CodeGenFunction *CGF = nullptr;
 504 };
 505
 506 template <class Derived, bool IsMove>
 507 struct GenBinaryFunc : CopyStructVisitor<Derived, IsMove>,
 508                        GenFuncBase<Derived> {
 509   GenBinaryFunc(ASTContext &Ctx) : CopyStructVisitor<Derived, IsMove>(Ctx) {}
 510
 511   void flushTrivialFields(std::array<Address, 2> Addrs) {
 512     CharUnits Size = this->End - this->Start;
 513
 514     if (Size.getQuantity() == 0)
 515       return;
 516
 517     Address DstAddr = this->getAddrWithOffset(Addrs[DstIdx], this->Start);
 518     Address SrcAddr = this->getAddrWithOffset(Addrs[SrcIdx], this->Start);
 519
 520     // Emit memcpy.
 521     if (Size.getQuantity() >= 16 ||
 522         !llvm::has_single_bit<uint32_t>(Size.getQuantity())) {
 523       llvm::Value *SizeVal =
 524           llvm::ConstantInt::get(this->CGF->SizeTy, Size.getQuantity());
 525       DstAddr = DstAddr.withElementType(this->CGF->Int8Ty);
 526       SrcAddr = SrcAddr.withElementType(this->CGF->Int8Ty);
 527       this->CGF->Builder.CreateMemCpy(DstAddr, SrcAddr, SizeVal, false);
 528     } else {
 529       llvm::Type *Ty = llvm::Type::getIntNTy(
 530           this->CGF->getLLVMContext(),
 531           Size.getQuantity() * this->CGF->getContext().getCharWidth());
 532       DstAddr = DstAddr.withElementType(Ty);
 533       SrcAddr = SrcAddr.withElementType(Ty);
 534       llvm::Value *SrcVal = this->CGF->Builder.CreateLoad(SrcAddr, false);
 535       this->CGF->Builder.CreateStore(SrcVal, DstAddr, false);
 536     }
 537
 538     this->Start = this->End = CharUnits::Zero();
 539   }
 540
 541   template <class... Ts>
 542   void visitVolatileTrivial(QualType FT, const FieldDecl *FD, CharUnits Offset,
 543                             std::array<Address, 2> Addrs) {
 544     LValue DstLV, SrcLV;
 545     if (FD) {
 546       // No need to copy zero-length bit-fields.
 547       if (FD->isZeroLengthBitField(this->CGF->getContext()))
 548         return;
 549
 550       QualType RT = QualType(FD->getParent()->getTypeForDecl(), 0);
 551       llvm::Type *Ty = this->CGF->ConvertType(RT);
 552       Address DstAddr = this->getAddrWithOffset(Addrs[DstIdx], Offset);
 553       LValue DstBase =
 554           this->CGF->MakeAddrLValue(DstAddr.withElementType(Ty), FT);
 555       DstLV = this->CGF->EmitLValueForField(DstBase, FD);
 556       Address SrcAddr = this->getAddrWithOffset(Addrs[SrcIdx], Offset);
 557       LValue SrcBase =
 558           this->CGF->MakeAddrLValue(SrcAddr.withElementType(Ty), FT);
 559       SrcLV = this->CGF->EmitLValueForField(SrcBase, FD);
 560     } else {
 561       llvm::Type *Ty = this->CGF->ConvertTypeForMem(FT);
 562       Address DstAddr = Addrs[DstIdx].withElementType(Ty);
 563       Address SrcAddr = Addrs[SrcIdx].withElementType(Ty);
 564       DstLV = this->CGF->MakeAddrLValue(DstAddr, FT);
 565       SrcLV = this->CGF->MakeAddrLValue(SrcAddr, FT);
 566     }
 567     RValue SrcVal = this->CGF->EmitLoadOfLValue(SrcLV, SourceLocation());
 568     this->CGF->EmitStoreThroughLValue(SrcVal, DstLV);
 569   }
 570 };
 571
 572 // These classes that emit the special functions for a non-trivial struct.
 573 struct GenDestructor : StructVisitor<GenDestructor>,
 574                        GenFuncBase<GenDestructor>,
 575                        DestructedTypeVisitor<GenDestructor> {
 576   using Super = DestructedTypeVisitor<GenDestructor>;
 577   GenDestructor(ASTContext &Ctx) : StructVisitor<GenDestructor>(Ctx) {}
 578
 579   void visitWithKind(QualType::DestructionKind DK, QualType FT,
 580                      const FieldDecl *FD, CharUnits CurStructOffset,
 581                      std::array<Address, 1> Addrs) {
 582     if (const auto *AT = getContext().getAsArrayType(FT)) {
 583       visitArray(DK, AT, FT.isVolatileQualified(), FD, CurStructOffset, Addrs);
 584       return;
 585     }
 586
 587     Super::visitWithKind(DK, FT, FD, CurStructOffset, Addrs);
 588   }
 589
 590   void visitARCStrong(QualType QT, const FieldDecl *FD,
 591                       CharUnits CurStructOffset, std::array<Address, 1> Addrs) {
 592     CGF->destroyARCStrongImprecise(
 593         *CGF, getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD), QT);
 594   }
 595
 596   void visitARCWeak(QualType QT, const FieldDecl *FD, CharUnits CurStructOffset,
 597                     std::array<Address, 1> Addrs) {
 598     CGF->destroyARCWeak(
 599         *CGF, getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD), QT);
 600   }
 601
 602   void callSpecialFunction(QualType FT, CharUnits Offset,
 603                            std::array<Address, 1> Addrs) {
 604     CGF->callCStructDestructor(
 605         CGF->MakeAddrLValue(getAddrWithOffset(Addrs[DstIdx], Offset), FT));
 606   }
 607 };
 608
 609 struct GenDefaultInitialize
 610     : StructVisitor<GenDefaultInitialize>,
 611       GenFuncBase<GenDefaultInitialize>,
 612       DefaultInitializedTypeVisitor<GenDefaultInitialize> {
 613   using Super = DefaultInitializedTypeVisitor<GenDefaultInitialize>;
 614   typedef GenFuncBase<GenDefaultInitialize> GenFuncBaseTy;
 615
 616   GenDefaultInitialize(ASTContext &Ctx)
 617       : StructVisitor<GenDefaultInitialize>(Ctx) {}
 618
 619   void visitWithKind(QualType::PrimitiveDefaultInitializeKind PDIK, QualType FT,
 620                      const FieldDecl *FD, CharUnits CurStructOffset,
 621                      std::array<Address, 1> Addrs) {
 622     if (const auto *AT = getContext().getAsArrayType(FT)) {
 623       visitArray(PDIK, AT, FT.isVolatileQualified(), FD, CurStructOffset,
 624                  Addrs);
 625       return;
 626     }
 627
 628     Super::visitWithKind(PDIK, FT, FD, CurStructOffset, Addrs);
 629   }
 630
 631   void visitARCStrong(QualType QT, const FieldDecl *FD,
 632                       CharUnits CurStructOffset, std::array<Address, 1> Addrs) {
 633     CGF->EmitNullInitialization(
 634         getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD), QT);
 635   }
 636
 637   void visitARCWeak(QualType QT, const FieldDecl *FD, CharUnits CurStructOffset,
 638                     std::array<Address, 1> Addrs) {
 639     CGF->EmitNullInitialization(
 640         getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD), QT);
 641   }
 642
 643   template <class FieldKind, size_t... Is>
 644   void visitArray(FieldKind FK, const ArrayType *AT, bool IsVolatile,
 645                   const FieldDecl *FD, CharUnits CurStructOffset,
 646                   std::array<Address, 1> Addrs) {
 647     if (!FK)
 648       return visitTrivial(QualType(AT, 0), FD, CurStructOffset, Addrs);
 649
 650     ASTContext &Ctx = getContext();
 651     CharUnits Size = Ctx.getTypeSizeInChars(QualType(AT, 0));
 652     QualType EltTy = Ctx.getBaseElementType(QualType(AT, 0));
 653
 654     if (Size < CharUnits::fromQuantity(16) || EltTy->getAs<RecordType>()) {
 655       GenFuncBaseTy::visitArray(FK, AT, IsVolatile, FD, CurStructOffset, Addrs);
 656       return;
 657     }
 658
 659     llvm::Constant *SizeVal = CGF->Builder.getInt64(Size.getQuantity());
 660     Address DstAddr = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 661     Address Loc = DstAddr.withElementType(CGF->Int8Ty);
 662     CGF->Builder.CreateMemSet(Loc, CGF->Builder.getInt8(0), SizeVal,
 663                               IsVolatile);
 664   }
 665
 666   void callSpecialFunction(QualType FT, CharUnits Offset,
 667                            std::array<Address, 1> Addrs) {
 668     CGF->callCStructDefaultConstructor(
 669         CGF->MakeAddrLValue(getAddrWithOffset(Addrs[DstIdx], Offset), FT));
 670   }
 671 };
 672
 673 struct GenCopyConstructor : GenBinaryFunc<GenCopyConstructor, false> {
 674   GenCopyConstructor(ASTContext &Ctx)
 675       : GenBinaryFunc<GenCopyConstructor, false>(Ctx) {}
 676
 677   void visitARCStrong(QualType QT, const FieldDecl *FD,
 678                       CharUnits CurStructOffset, std::array<Address, 2> Addrs) {
 679     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 680     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 681     llvm::Value *SrcVal = CGF->EmitLoadOfScalar(
 682         Addrs[SrcIdx], QT.isVolatileQualified(), QT, SourceLocation());
 683     llvm::Value *Val = CGF->EmitARCRetain(QT, SrcVal);
 684     CGF->EmitStoreOfScalar(Val, CGF->MakeAddrLValue(Addrs[DstIdx], QT), true);
 685   }
 686
 687   void visitARCWeak(QualType QT, const FieldDecl *FD, CharUnits CurStructOffset,
 688                     std::array<Address, 2> Addrs) {
 689     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 690     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 691     CGF->EmitARCCopyWeak(Addrs[DstIdx], Addrs[SrcIdx]);
 692   }
 693
 694   void callSpecialFunction(QualType FT, CharUnits Offset,
 695                            std::array<Address, 2> Addrs) {
 696     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], Offset);
 697     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], Offset);
 698     CGF->callCStructCopyConstructor(CGF->MakeAddrLValue(Addrs[DstIdx], FT),
 699                                     CGF->MakeAddrLValue(Addrs[SrcIdx], FT));
 700   }
 701 };
 702
 703 struct GenMoveConstructor : GenBinaryFunc<GenMoveConstructor, true> {
 704   GenMoveConstructor(ASTContext &Ctx)
 705       : GenBinaryFunc<GenMoveConstructor, true>(Ctx) {}
 706
 707   void visitARCStrong(QualType QT, const FieldDecl *FD,
 708                       CharUnits CurStructOffset, std::array<Address, 2> Addrs) {
 709     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 710     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 711     LValue SrcLV = CGF->MakeAddrLValue(Addrs[SrcIdx], QT);
 712     llvm::Value *SrcVal =
 713         CGF->EmitLoadOfLValue(SrcLV, SourceLocation()).getScalarVal();
 714     CGF->EmitStoreOfScalar(getNullForVariable(SrcLV.getAddress(*CGF)), SrcLV);
 715     CGF->EmitStoreOfScalar(SrcVal, CGF->MakeAddrLValue(Addrs[DstIdx], QT),
 716                            /* isInitialization */ true);
 717   }
 718
 719   void visitARCWeak(QualType QT, const FieldDecl *FD, CharUnits CurStructOffset,
 720                     std::array<Address, 2> Addrs) {
 721     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 722     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 723     CGF->EmitARCMoveWeak(Addrs[DstIdx], Addrs[SrcIdx]);
 724   }
 725
 726   void callSpecialFunction(QualType FT, CharUnits Offset,
 727                            std::array<Address, 2> Addrs) {
 728     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], Offset);
 729     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], Offset);
 730     CGF->callCStructMoveConstructor(CGF->MakeAddrLValue(Addrs[DstIdx], FT),
 731                                     CGF->MakeAddrLValue(Addrs[SrcIdx], FT));
 732   }
 733 };
 734
 735 struct GenCopyAssignment : GenBinaryFunc<GenCopyAssignment, false> {
 736   GenCopyAssignment(ASTContext &Ctx)
 737       : GenBinaryFunc<GenCopyAssignment, false>(Ctx) {}
 738
 739   void visitARCStrong(QualType QT, const FieldDecl *FD,
 740                       CharUnits CurStructOffset, std::array<Address, 2> Addrs) {
 741     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 742     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 743     llvm::Value *SrcVal = CGF->EmitLoadOfScalar(
 744         Addrs[SrcIdx], QT.isVolatileQualified(), QT, SourceLocation());
 745     CGF->EmitARCStoreStrong(CGF->MakeAddrLValue(Addrs[DstIdx], QT), SrcVal,
 746                             false);
 747   }
 748
 749   void visitARCWeak(QualType QT, const FieldDecl *FD, CharUnits CurStructOffset,
 750                     std::array<Address, 2> Addrs) {
 751     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 752     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 753     CGF->emitARCCopyAssignWeak(QT, Addrs[DstIdx], Addrs[SrcIdx]);
 754   }
 755
 756   void callSpecialFunction(QualType FT, CharUnits Offset,
 757                            std::array<Address, 2> Addrs) {
 758     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], Offset);
 759     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], Offset);
 760     CGF->callCStructCopyAssignmentOperator(
 761         CGF->MakeAddrLValue(Addrs[DstIdx], FT),
 762         CGF->MakeAddrLValue(Addrs[SrcIdx], FT));
 763   }
 764 };
 765
 766 struct GenMoveAssignment : GenBinaryFunc<GenMoveAssignment, true> {
 767   GenMoveAssignment(ASTContext &Ctx)
 768       : GenBinaryFunc<GenMoveAssignment, true>(Ctx) {}
 769
 770   void visitARCStrong(QualType QT, const FieldDecl *FD,
 771                       CharUnits CurStructOffset, std::array<Address, 2> Addrs) {
 772     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 773     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 774     LValue SrcLV = CGF->MakeAddrLValue(Addrs[SrcIdx], QT);
 775     llvm::Value *SrcVal =
 776         CGF->EmitLoadOfLValue(SrcLV, SourceLocation()).getScalarVal();
 777     CGF->EmitStoreOfScalar(getNullForVariable(SrcLV.getAddress(*CGF)), SrcLV);
 778     LValue DstLV = CGF->MakeAddrLValue(Addrs[DstIdx], QT);
 779     llvm::Value *DstVal =
 780         CGF->EmitLoadOfLValue(DstLV, SourceLocation()).getScalarVal();
 781     CGF->EmitStoreOfScalar(SrcVal, DstLV);
 782     CGF->EmitARCRelease(DstVal, ARCImpreciseLifetime);
 783   }
 784
 785   void visitARCWeak(QualType QT, const FieldDecl *FD, CharUnits CurStructOffset,
 786                     std::array<Address, 2> Addrs) {
 787     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], CurStructOffset, FD);
 788     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], CurStructOffset, FD);
 789     CGF->emitARCMoveAssignWeak(QT, Addrs[DstIdx], Addrs[SrcIdx]);
 790   }
 791
 792   void callSpecialFunction(QualType FT, CharUnits Offset,
 793                            std::array<Address, 2> Addrs) {
 794     Addrs[DstIdx] = getAddrWithOffset(Addrs[DstIdx], Offset);
 795     Addrs[SrcIdx] = getAddrWithOffset(Addrs[SrcIdx], Offset);
 796     CGF->callCStructMoveAssignmentOperator(
 797         CGF->MakeAddrLValue(Addrs[DstIdx], FT),
 798         CGF->MakeAddrLValue(Addrs[SrcIdx], FT));
 799   }
 800 };
 801
 802 } // namespace
 803
 804 void CodeGenFunction::destroyNonTrivialCStruct(CodeGenFunction &CGF,
 805                                                Address Addr, QualType Type) {
 806   CGF.callCStructDestructor(CGF.MakeAddrLValue(Addr, Type));
 807 }
 808
 809 // Default-initialize a variable that is a non-trivial struct or an array of
 810 // such structure.
 811 void CodeGenFunction::defaultInitNonTrivialCStructVar(LValue Dst) {
 812   GenDefaultInitialize Gen(getContext());
 813   Address DstPtr = Dst.getAddress(*this).withElementType(CGM.Int8PtrTy);
 814   Gen.setCGF(this);
 815   QualType QT = Dst.getType();
 816   QT = Dst.isVolatile() ? QT.withVolatile() : QT;
 817   Gen.visit(QT, nullptr, CharUnits::Zero(), std::array<Address, 1>({{DstPtr}}));
 818 }
 819
 820 template <class G, size_t N>
 821 static void callSpecialFunction(G &&Gen, StringRef FuncName, QualType QT,
 822                                 bool IsVolatile, CodeGenFunction &CGF,
 823                                 std::array<Address, N> Addrs) {
 824   auto SetArtificialLoc = ApplyDebugLocation::CreateArtificial(CGF);
 825   for (unsigned I = 0; I < N; ++I)
 826     Addrs[I] = Addrs[I].withElementType(CGF.CGM.Int8PtrTy);
 827   QT = IsVolatile ? QT.withVolatile() : QT;
 828   Gen.callFunc(FuncName, QT, Addrs, CGF);
 829 }
 830
 831 template <class G, size_t N>
 832 static llvm::Function *
 833 getSpecialFunction(G &&Gen, StringRef FuncName, QualType QT, bool IsVolatile,
 834                    std::array<CharUnits, N> Alignments, CodeGenModule &CGM) {
 835   QT = IsVolatile ? QT.withVolatile() : QT;
 836   // The following call requires an array of addresses as arguments, but doesn't
 837   // actually use them (it overwrites them with the addresses of the arguments
 838   // of the created function).
 839   return Gen.getFunction(FuncName, QT, Alignments, CGM);
 840 }
 841
 842 // Functions to emit calls to the special functions of a non-trivial C struct.
 843 void CodeGenFunction::callCStructDefaultConstructor(LValue Dst) {
 844   bool IsVolatile = Dst.isVolatile();
 845   Address DstPtr = Dst.getAddress(*this);
 846   QualType QT = Dst.getType();
 847   GenDefaultInitializeFuncName GenName(DstPtr.getAlignment(), getContext());
 848   std::string FuncName = GenName.getName(QT, IsVolatile);
 849   callSpecialFunction(GenDefaultInitialize(getContext()), FuncName, QT,
 850                       IsVolatile, *this, std::array<Address, 1>({{DstPtr}}));
 851 }
 852
 853 std::string CodeGenFunction::getNonTrivialCopyConstructorStr(
 854     QualType QT, CharUnits Alignment, bool IsVolatile, ASTContext &Ctx) {
 855   GenBinaryFuncName<false> GenName("", Alignment, Alignment, Ctx);
 856   return GenName.getName(QT, IsVolatile);
 857 }
 858
 859 std::string CodeGenFunction::getNonTrivialDestructorStr(QualType QT,
 860                                                         CharUnits Alignment,
 861                                                         bool IsVolatile,
 862                                                         ASTContext &Ctx) {
 863   GenDestructorFuncName GenName("", Alignment, Ctx);
 864   return GenName.getName(QT, IsVolatile);
 865 }
 866
 867 void CodeGenFunction::callCStructDestructor(LValue Dst) {
 868   bool IsVolatile = Dst.isVolatile();
 869   Address DstPtr = Dst.getAddress(*this);
 870   QualType QT = Dst.getType();
 871   GenDestructorFuncName GenName("__destructor_", DstPtr.getAlignment(),
 872                                 getContext());
 873   std::string FuncName = GenName.getName(QT, IsVolatile);
 874   callSpecialFunction(GenDestructor(getContext()), FuncName, QT, IsVolatile,
 875                       *this, std::array<Address, 1>({{DstPtr}}));
 876 }
 877
 878 void CodeGenFunction::callCStructCopyConstructor(LValue Dst, LValue Src) {
 879   bool IsVolatile = Dst.isVolatile() || Src.isVolatile();
 880   Address DstPtr = Dst.getAddress(*this), SrcPtr = Src.getAddress(*this);
 881   QualType QT = Dst.getType();
 882   GenBinaryFuncName<false> GenName("__copy_constructor_", DstPtr.getAlignment(),
 883                                    SrcPtr.getAlignment(), getContext());
 884   std::string FuncName = GenName.getName(QT, IsVolatile);
 885   callSpecialFunction(GenCopyConstructor(getContext()), FuncName, QT,
 886                       IsVolatile, *this,
 887                       std::array<Address, 2>({{DstPtr, SrcPtr}}));
 888 }
 889
 890 void CodeGenFunction::callCStructCopyAssignmentOperator(LValue Dst, LValue Src
 891
 892 ) {
 893   bool IsVolatile = Dst.isVolatile() || Src.isVolatile();
 894   Address DstPtr = Dst.getAddress(*this), SrcPtr = Src.getAddress(*this);
 895   QualType QT = Dst.getType();
 896   GenBinaryFuncName<false> GenName("__copy_assignment_", DstPtr.getAlignment(),
 897                                    SrcPtr.getAlignment(), getContext());
 898   std::string FuncName = GenName.getName(QT, IsVolatile);
 899   callSpecialFunction(GenCopyAssignment(getContext()), FuncName, QT, IsVolatile,
 900                       *this, std::array<Address, 2>({{DstPtr, SrcPtr}}));
 901 }
 902
 903 void CodeGenFunction::callCStructMoveConstructor(LValue Dst, LValue Src) {
 904   bool IsVolatile = Dst.isVolatile() || Src.isVolatile();
 905   Address DstPtr = Dst.getAddress(*this), SrcPtr = Src.getAddress(*this);
 906   QualType QT = Dst.getType();
 907   GenBinaryFuncName<true> GenName("__move_constructor_", DstPtr.getAlignment(),
 908                                   SrcPtr.getAlignment(), getContext());
 909   std::string FuncName = GenName.getName(QT, IsVolatile);
 910   callSpecialFunction(GenMoveConstructor(getContext()), FuncName, QT,
 911                       IsVolatile, *this,
 912                       std::array<Address, 2>({{DstPtr, SrcPtr}}));
 913 }
 914
 915 void CodeGenFunction::callCStructMoveAssignmentOperator(LValue Dst, LValue Src
 916
 917 ) {
 918   bool IsVolatile = Dst.isVolatile() || Src.isVolatile();
 919   Address DstPtr = Dst.getAddress(*this), SrcPtr = Src.getAddress(*this);
 920   QualType QT = Dst.getType();
 921   GenBinaryFuncName<true> GenName("__move_assignment_", DstPtr.getAlignment(),
 922                                   SrcPtr.getAlignment(), getContext());
 923   std::string FuncName = GenName.getName(QT, IsVolatile);
 924   callSpecialFunction(GenMoveAssignment(getContext()), FuncName, QT, IsVolatile,
 925                       *this, std::array<Address, 2>({{DstPtr, SrcPtr}}));
 926 }
 927
 928 llvm::Function *clang::CodeGen::getNonTrivialCStructDefaultConstructor(
 929     CodeGenModule &CGM, CharUnits DstAlignment, bool IsVolatile, QualType QT) {
 930   ASTContext &Ctx = CGM.getContext();
 931   GenDefaultInitializeFuncName GenName(DstAlignment, Ctx);
 932   std::string FuncName = GenName.getName(QT, IsVolatile);
 933   return getSpecialFunction(GenDefaultInitialize(Ctx), FuncName, QT, IsVolatile,
 934                             std::array<CharUnits, 1>({{DstAlignment}}), CGM);
 935 }
 936
 937 llvm::Function *clang::CodeGen::getNonTrivialCStructCopyConstructor(
 938     CodeGenModule &CGM, CharUnits DstAlignment, CharUnits SrcAlignment,
 939     bool IsVolatile, QualType QT) {
 940   ASTContext &Ctx = CGM.getContext();
 941   GenBinaryFuncName<false> GenName("__copy_constructor_", DstAlignment,
 942                                    SrcAlignment, Ctx);
 943   std::string FuncName = GenName.getName(QT, IsVolatile);
 944   return getSpecialFunction(
 945       GenCopyConstructor(Ctx), FuncName, QT, IsVolatile,
 946       std::array<CharUnits, 2>({{DstAlignment, SrcAlignment}}), CGM);
 947 }
 948
 949 llvm::Function *clang::CodeGen::getNonTrivialCStructMoveConstructor(
 950     CodeGenModule &CGM, CharUnits DstAlignment, CharUnits SrcAlignment,
 951     bool IsVolatile, QualType QT) {
 952   ASTContext &Ctx = CGM.getContext();
 953   GenBinaryFuncName<true> GenName("__move_constructor_", DstAlignment,
 954                                   SrcAlignment, Ctx);
 955   std::string FuncName = GenName.getName(QT, IsVolatile);
 956   return getSpecialFunction(
 957       GenMoveConstructor(Ctx), FuncName, QT, IsVolatile,
 958       std::array<CharUnits, 2>({{DstAlignment, SrcAlignment}}), CGM);
 959 }
 960
 961 llvm::Function *clang::CodeGen::getNonTrivialCStructCopyAssignmentOperator(
 962     CodeGenModule &CGM, CharUnits DstAlignment, CharUnits SrcAlignment,
 963     bool IsVolatile, QualType QT) {
 964   ASTContext &Ctx = CGM.getContext();
 965   GenBinaryFuncName<false> GenName("__copy_assignment_", DstAlignment,
 966                                    SrcAlignment, Ctx);
 967   std::string FuncName = GenName.getName(QT, IsVolatile);
 968   return getSpecialFunction(
 969       GenCopyAssignment(Ctx), FuncName, QT, IsVolatile,
 970       std::array<CharUnits, 2>({{DstAlignment, SrcAlignment}}), CGM);
 971 }
 972
 973 llvm::Function *clang::CodeGen::getNonTrivialCStructMoveAssignmentOperator(
 974     CodeGenModule &CGM, CharUnits DstAlignment, CharUnits SrcAlignment,
 975     bool IsVolatile, QualType QT) {
 976   ASTContext &Ctx = CGM.getContext();
 977   GenBinaryFuncName<true> GenName("__move_assignment_", DstAlignment,
 978                                   SrcAlignment, Ctx);
 979   std::string FuncName = GenName.getName(QT, IsVolatile);
 980   return getSpecialFunction(
 981       GenMoveAssignment(Ctx), FuncName, QT, IsVolatile,
 982       std::array<CharUnits, 2>({{DstAlignment, SrcAlignment}}), CGM);
 983 }
 984
 985 llvm::Function *clang::CodeGen::getNonTrivialCStructDestructor(
 986     CodeGenModule &CGM, CharUnits DstAlignment, bool IsVolatile, QualType QT) {
 987   ASTContext &Ctx = CGM.getContext();
 988   GenDestructorFuncName GenName("__destructor_", DstAlignment, Ctx);
 989   std::string FuncName = GenName.getName(QT, IsVolatile);
 990   return getSpecialFunction(GenDestructor(Ctx), FuncName, QT, IsVolatile,
 991                             std::array<CharUnits, 1>({{DstAlignment}}), CGM);
 992 }