clang  9.0.0svn
MicrosoftCXXABI.cpp
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1 //===--- MicrosoftCXXABI.cpp - Emit LLVM Code from ASTs for a Module ------===//
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 provides C++ code generation targeting the Microsoft Visual C++ ABI.
10 // The class in this file generates structures that follow the Microsoft
11 // Visual C++ ABI, which is actually not very well documented at all outside
12 // of Microsoft.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #include "CGCXXABI.h"
17 #include "CGCleanup.h"
18 #include "CGVTables.h"
19 #include "CodeGenModule.h"
20 #include "CodeGenTypes.h"
21 #include "TargetInfo.h"
23 #include "clang/AST/Decl.h"
24 #include "clang/AST/DeclCXX.h"
25 #include "clang/AST/StmtCXX.h"
27 #include "llvm/ADT/StringExtras.h"
28 #include "llvm/ADT/StringSet.h"
29 #include "llvm/IR/Intrinsics.h"
30 
31 using namespace clang;
32 using namespace CodeGen;
33 
34 namespace {
35 
36 /// Holds all the vbtable globals for a given class.
37 struct VBTableGlobals {
38  const VPtrInfoVector *VBTables;
40 };
41 
42 class MicrosoftCXXABI : public CGCXXABI {
43 public:
44  MicrosoftCXXABI(CodeGenModule &CGM)
45  : CGCXXABI(CGM), BaseClassDescriptorType(nullptr),
46  ClassHierarchyDescriptorType(nullptr),
47  CompleteObjectLocatorType(nullptr), CatchableTypeType(nullptr),
48  ThrowInfoType(nullptr) {}
49 
50  bool HasThisReturn(GlobalDecl GD) const override;
51  bool hasMostDerivedReturn(GlobalDecl GD) const override;
52 
53  bool classifyReturnType(CGFunctionInfo &FI) const override;
54 
55  RecordArgABI getRecordArgABI(const CXXRecordDecl *RD) const override;
56 
57  bool isSRetParameterAfterThis() const override { return true; }
58 
59  bool isThisCompleteObject(GlobalDecl GD) const override {
60  // The Microsoft ABI doesn't use separate complete-object vs.
61  // base-object variants of constructors, but it does of destructors.
62  if (isa<CXXDestructorDecl>(GD.getDecl())) {
63  switch (GD.getDtorType()) {
64  case Dtor_Complete:
65  case Dtor_Deleting:
66  return true;
67 
68  case Dtor_Base:
69  return false;
70 
71  case Dtor_Comdat: llvm_unreachable("emitting dtor comdat as function?");
72  }
73  llvm_unreachable("bad dtor kind");
74  }
75 
76  // No other kinds.
77  return false;
78  }
79 
80  size_t getSrcArgforCopyCtor(const CXXConstructorDecl *CD,
81  FunctionArgList &Args) const override {
82  assert(Args.size() >= 2 &&
83  "expected the arglist to have at least two args!");
84  // The 'most_derived' parameter goes second if the ctor is variadic and
85  // has v-bases.
86  if (CD->getParent()->getNumVBases() > 0 &&
87  CD->getType()->castAs<FunctionProtoType>()->isVariadic())
88  return 2;
89  return 1;
90  }
91 
92  std::vector<CharUnits> getVBPtrOffsets(const CXXRecordDecl *RD) override {
93  std::vector<CharUnits> VBPtrOffsets;
94  const ASTContext &Context = getContext();
95  const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
96 
97  const VBTableGlobals &VBGlobals = enumerateVBTables(RD);
98  for (const std::unique_ptr<VPtrInfo> &VBT : *VBGlobals.VBTables) {
99  const ASTRecordLayout &SubobjectLayout =
100  Context.getASTRecordLayout(VBT->IntroducingObject);
101  CharUnits Offs = VBT->NonVirtualOffset;
102  Offs += SubobjectLayout.getVBPtrOffset();
103  if (VBT->getVBaseWithVPtr())
104  Offs += Layout.getVBaseClassOffset(VBT->getVBaseWithVPtr());
105  VBPtrOffsets.push_back(Offs);
106  }
107  llvm::array_pod_sort(VBPtrOffsets.begin(), VBPtrOffsets.end());
108  return VBPtrOffsets;
109  }
110 
111  StringRef GetPureVirtualCallName() override { return "_purecall"; }
112  StringRef GetDeletedVirtualCallName() override { return "_purecall"; }
113 
114  void emitVirtualObjectDelete(CodeGenFunction &CGF, const CXXDeleteExpr *DE,
115  Address Ptr, QualType ElementType,
116  const CXXDestructorDecl *Dtor) override;
117 
118  void emitRethrow(CodeGenFunction &CGF, bool isNoReturn) override;
119  void emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) override;
120 
121  void emitBeginCatch(CodeGenFunction &CGF, const CXXCatchStmt *C) override;
122 
123  llvm::GlobalVariable *getMSCompleteObjectLocator(const CXXRecordDecl *RD,
124  const VPtrInfo &Info);
125 
126  llvm::Constant *getAddrOfRTTIDescriptor(QualType Ty) override;
128  getAddrOfCXXCatchHandlerType(QualType Ty, QualType CatchHandlerType) override;
129 
130  /// MSVC needs an extra flag to indicate a catchall.
131  CatchTypeInfo getCatchAllTypeInfo() override {
132  return CatchTypeInfo{nullptr, 0x40};
133  }
134 
135  bool shouldTypeidBeNullChecked(bool IsDeref, QualType SrcRecordTy) override;
136  void EmitBadTypeidCall(CodeGenFunction &CGF) override;
137  llvm::Value *EmitTypeid(CodeGenFunction &CGF, QualType SrcRecordTy,
138  Address ThisPtr,
139  llvm::Type *StdTypeInfoPtrTy) override;
140 
141  bool shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
142  QualType SrcRecordTy) override;
143 
144  llvm::Value *EmitDynamicCastCall(CodeGenFunction &CGF, Address Value,
145  QualType SrcRecordTy, QualType DestTy,
146  QualType DestRecordTy,
147  llvm::BasicBlock *CastEnd) override;
148 
149  llvm::Value *EmitDynamicCastToVoid(CodeGenFunction &CGF, Address Value,
150  QualType SrcRecordTy,
151  QualType DestTy) override;
152 
153  bool EmitBadCastCall(CodeGenFunction &CGF) override;
154  bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const override {
155  return false;
156  }
157 
158  llvm::Value *
159  GetVirtualBaseClassOffset(CodeGenFunction &CGF, Address This,
160  const CXXRecordDecl *ClassDecl,
161  const CXXRecordDecl *BaseClassDecl) override;
162 
163  llvm::BasicBlock *
164  EmitCtorCompleteObjectHandler(CodeGenFunction &CGF,
165  const CXXRecordDecl *RD) override;
166 
167  llvm::BasicBlock *
168  EmitDtorCompleteObjectHandler(CodeGenFunction &CGF);
169 
170  void initializeHiddenVirtualInheritanceMembers(CodeGenFunction &CGF,
171  const CXXRecordDecl *RD) override;
172 
173  void EmitCXXConstructors(const CXXConstructorDecl *D) override;
174 
175  // Background on MSVC destructors
176  // ==============================
177  //
178  // Both Itanium and MSVC ABIs have destructor variants. The variant names
179  // roughly correspond in the following way:
180  // Itanium Microsoft
181  // Base -> no name, just ~Class
182  // Complete -> vbase destructor
183  // Deleting -> scalar deleting destructor
184  // vector deleting destructor
185  //
186  // The base and complete destructors are the same as in Itanium, although the
187  // complete destructor does not accept a VTT parameter when there are virtual
188  // bases. A separate mechanism involving vtordisps is used to ensure that
189  // virtual methods of destroyed subobjects are not called.
190  //
191  // The deleting destructors accept an i32 bitfield as a second parameter. Bit
192  // 1 indicates if the memory should be deleted. Bit 2 indicates if the this
193  // pointer points to an array. The scalar deleting destructor assumes that
194  // bit 2 is zero, and therefore does not contain a loop.
195  //
196  // For virtual destructors, only one entry is reserved in the vftable, and it
197  // always points to the vector deleting destructor. The vector deleting
198  // destructor is the most general, so it can be used to destroy objects in
199  // place, delete single heap objects, or delete arrays.
200  //
201  // A TU defining a non-inline destructor is only guaranteed to emit a base
202  // destructor, and all of the other variants are emitted on an as-needed basis
203  // in COMDATs. Because a non-base destructor can be emitted in a TU that
204  // lacks a definition for the destructor, non-base destructors must always
205  // delegate to or alias the base destructor.
206 
207  AddedStructorArgs
208  buildStructorSignature(GlobalDecl GD,
209  SmallVectorImpl<CanQualType> &ArgTys) override;
210 
211  /// Non-base dtors should be emitted as delegating thunks in this ABI.
212  bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
213  CXXDtorType DT) const override {
214  return DT != Dtor_Base;
215  }
216 
217  void setCXXDestructorDLLStorage(llvm::GlobalValue *GV,
218  const CXXDestructorDecl *Dtor,
219  CXXDtorType DT) const override;
220 
221  llvm::GlobalValue::LinkageTypes
222  getCXXDestructorLinkage(GVALinkage Linkage, const CXXDestructorDecl *Dtor,
223  CXXDtorType DT) const override;
224 
225  void EmitCXXDestructors(const CXXDestructorDecl *D) override;
226 
227  const CXXRecordDecl *
228  getThisArgumentTypeForMethod(const CXXMethodDecl *MD) override {
229  if (MD->isVirtual() && !isa<CXXDestructorDecl>(MD)) {
231  CGM.getMicrosoftVTableContext().getMethodVFTableLocation(MD);
232  // The vbases might be ordered differently in the final overrider object
233  // and the complete object, so the "this" argument may sometimes point to
234  // memory that has no particular type (e.g. past the complete object).
235  // In this case, we just use a generic pointer type.
236  // FIXME: might want to have a more precise type in the non-virtual
237  // multiple inheritance case.
238  if (ML.VBase || !ML.VFPtrOffset.isZero())
239  return nullptr;
240  }
241  return MD->getParent();
242  }
243 
244  Address
245  adjustThisArgumentForVirtualFunctionCall(CodeGenFunction &CGF, GlobalDecl GD,
246  Address This,
247  bool VirtualCall) override;
248 
249  void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
250  FunctionArgList &Params) override;
251 
252  void EmitInstanceFunctionProlog(CodeGenFunction &CGF) override;
253 
254  AddedStructorArgs
255  addImplicitConstructorArgs(CodeGenFunction &CGF, const CXXConstructorDecl *D,
256  CXXCtorType Type, bool ForVirtualBase,
257  bool Delegating, CallArgList &Args) override;
258 
259  void EmitDestructorCall(CodeGenFunction &CGF, const CXXDestructorDecl *DD,
260  CXXDtorType Type, bool ForVirtualBase,
261  bool Delegating, Address This) override;
262 
263  void emitVTableTypeMetadata(const VPtrInfo &Info, const CXXRecordDecl *RD,
264  llvm::GlobalVariable *VTable);
265 
266  void emitVTableDefinitions(CodeGenVTables &CGVT,
267  const CXXRecordDecl *RD) override;
268 
269  bool isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
270  CodeGenFunction::VPtr Vptr) override;
271 
272  /// Don't initialize vptrs if dynamic class
273  /// is marked with with the 'novtable' attribute.
274  bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass) override {
275  return !VTableClass->hasAttr<MSNoVTableAttr>();
276  }
277 
278  llvm::Constant *
279  getVTableAddressPoint(BaseSubobject Base,
280  const CXXRecordDecl *VTableClass) override;
281 
282  llvm::Value *getVTableAddressPointInStructor(
283  CodeGenFunction &CGF, const CXXRecordDecl *VTableClass,
284  BaseSubobject Base, const CXXRecordDecl *NearestVBase) override;
285 
286  llvm::Constant *
287  getVTableAddressPointForConstExpr(BaseSubobject Base,
288  const CXXRecordDecl *VTableClass) override;
289 
290  llvm::GlobalVariable *getAddrOfVTable(const CXXRecordDecl *RD,
291  CharUnits VPtrOffset) override;
292 
293  CGCallee getVirtualFunctionPointer(CodeGenFunction &CGF, GlobalDecl GD,
294  Address This, llvm::Type *Ty,
295  SourceLocation Loc) override;
296 
297  llvm::Value *EmitVirtualDestructorCall(CodeGenFunction &CGF,
298  const CXXDestructorDecl *Dtor,
299  CXXDtorType DtorType,
300  Address This,
301  const CXXMemberCallExpr *CE) override;
302 
303  void adjustCallArgsForDestructorThunk(CodeGenFunction &CGF, GlobalDecl GD,
304  CallArgList &CallArgs) override {
305  assert(GD.getDtorType() == Dtor_Deleting &&
306  "Only deleting destructor thunks are available in this ABI");
307  CallArgs.add(RValue::get(getStructorImplicitParamValue(CGF)),
308  getContext().IntTy);
309  }
310 
311  void emitVirtualInheritanceTables(const CXXRecordDecl *RD) override;
312 
313  llvm::GlobalVariable *
314  getAddrOfVBTable(const VPtrInfo &VBT, const CXXRecordDecl *RD,
315  llvm::GlobalVariable::LinkageTypes Linkage);
316 
317  llvm::GlobalVariable *
318  getAddrOfVirtualDisplacementMap(const CXXRecordDecl *SrcRD,
319  const CXXRecordDecl *DstRD) {
320  SmallString<256> OutName;
321  llvm::raw_svector_ostream Out(OutName);
322  getMangleContext().mangleCXXVirtualDisplacementMap(SrcRD, DstRD, Out);
323  StringRef MangledName = OutName.str();
324 
325  if (auto *VDispMap = CGM.getModule().getNamedGlobal(MangledName))
326  return VDispMap;
327 
328  MicrosoftVTableContext &VTContext = CGM.getMicrosoftVTableContext();
329  unsigned NumEntries = 1 + SrcRD->getNumVBases();
330  SmallVector<llvm::Constant *, 4> Map(NumEntries,
331  llvm::UndefValue::get(CGM.IntTy));
332  Map[0] = llvm::ConstantInt::get(CGM.IntTy, 0);
333  bool AnyDifferent = false;
334  for (const auto &I : SrcRD->vbases()) {
335  const CXXRecordDecl *VBase = I.getType()->getAsCXXRecordDecl();
336  if (!DstRD->isVirtuallyDerivedFrom(VBase))
337  continue;
338 
339  unsigned SrcVBIndex = VTContext.getVBTableIndex(SrcRD, VBase);
340  unsigned DstVBIndex = VTContext.getVBTableIndex(DstRD, VBase);
341  Map[SrcVBIndex] = llvm::ConstantInt::get(CGM.IntTy, DstVBIndex * 4);
342  AnyDifferent |= SrcVBIndex != DstVBIndex;
343  }
344  // This map would be useless, don't use it.
345  if (!AnyDifferent)
346  return nullptr;
347 
348  llvm::ArrayType *VDispMapTy = llvm::ArrayType::get(CGM.IntTy, Map.size());
349  llvm::Constant *Init = llvm::ConstantArray::get(VDispMapTy, Map);
350  llvm::GlobalValue::LinkageTypes Linkage =
351  SrcRD->isExternallyVisible() && DstRD->isExternallyVisible()
352  ? llvm::GlobalValue::LinkOnceODRLinkage
354  auto *VDispMap = new llvm::GlobalVariable(
355  CGM.getModule(), VDispMapTy, /*Constant=*/true, Linkage,
356  /*Initializer=*/Init, MangledName);
357  return VDispMap;
358  }
359 
360  void emitVBTableDefinition(const VPtrInfo &VBT, const CXXRecordDecl *RD,
361  llvm::GlobalVariable *GV) const;
362 
363  void setThunkLinkage(llvm::Function *Thunk, bool ForVTable,
364  GlobalDecl GD, bool ReturnAdjustment) override {
365  GVALinkage Linkage =
366  getContext().GetGVALinkageForFunction(cast<FunctionDecl>(GD.getDecl()));
367 
368  if (Linkage == GVA_Internal)
369  Thunk->setLinkage(llvm::GlobalValue::InternalLinkage);
370  else if (ReturnAdjustment)
371  Thunk->setLinkage(llvm::GlobalValue::WeakODRLinkage);
372  else
373  Thunk->setLinkage(llvm::GlobalValue::LinkOnceODRLinkage);
374  }
375 
376  bool exportThunk() override { return false; }
377 
378  llvm::Value *performThisAdjustment(CodeGenFunction &CGF, Address This,
379  const ThisAdjustment &TA) override;
380 
381  llvm::Value *performReturnAdjustment(CodeGenFunction &CGF, Address Ret,
382  const ReturnAdjustment &RA) override;
383 
384  void EmitThreadLocalInitFuncs(
385  CodeGenModule &CGM, ArrayRef<const VarDecl *> CXXThreadLocals,
386  ArrayRef<llvm::Function *> CXXThreadLocalInits,
387  ArrayRef<const VarDecl *> CXXThreadLocalInitVars) override;
388 
389  bool usesThreadWrapperFunction() const override { return false; }
390  LValue EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF, const VarDecl *VD,
391  QualType LValType) override;
392 
393  void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
394  llvm::GlobalVariable *DeclPtr,
395  bool PerformInit) override;
396  void registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
397  llvm::FunctionCallee Dtor,
398  llvm::Constant *Addr) override;
399 
400  // ==== Notes on array cookies =========
401  //
402  // MSVC seems to only use cookies when the class has a destructor; a
403  // two-argument usual array deallocation function isn't sufficient.
404  //
405  // For example, this code prints "100" and "1":
406  // struct A {
407  // char x;
408  // void *operator new[](size_t sz) {
409  // printf("%u\n", sz);
410  // return malloc(sz);
411  // }
412  // void operator delete[](void *p, size_t sz) {
413  // printf("%u\n", sz);
414  // free(p);
415  // }
416  // };
417  // int main() {
418  // A *p = new A[100];
419  // delete[] p;
420  // }
421  // Whereas it prints "104" and "104" if you give A a destructor.
422 
423  bool requiresArrayCookie(const CXXDeleteExpr *expr,
424  QualType elementType) override;
425  bool requiresArrayCookie(const CXXNewExpr *expr) override;
426  CharUnits getArrayCookieSizeImpl(QualType type) override;
427  Address InitializeArrayCookie(CodeGenFunction &CGF,
428  Address NewPtr,
429  llvm::Value *NumElements,
430  const CXXNewExpr *expr,
431  QualType ElementType) override;
432  llvm::Value *readArrayCookieImpl(CodeGenFunction &CGF,
433  Address allocPtr,
434  CharUnits cookieSize) override;
435 
436  friend struct MSRTTIBuilder;
437 
438  bool isImageRelative() const {
439  return CGM.getTarget().getPointerWidth(/*AddressSpace=*/0) == 64;
440  }
441 
442  // 5 routines for constructing the llvm types for MS RTTI structs.
443  llvm::StructType *getTypeDescriptorType(StringRef TypeInfoString) {
444  llvm::SmallString<32> TDTypeName("rtti.TypeDescriptor");
445  TDTypeName += llvm::utostr(TypeInfoString.size());
446  llvm::StructType *&TypeDescriptorType =
447  TypeDescriptorTypeMap[TypeInfoString.size()];
448  if (TypeDescriptorType)
449  return TypeDescriptorType;
450  llvm::Type *FieldTypes[] = {
451  CGM.Int8PtrPtrTy,
452  CGM.Int8PtrTy,
453  llvm::ArrayType::get(CGM.Int8Ty, TypeInfoString.size() + 1)};
454  TypeDescriptorType =
455  llvm::StructType::create(CGM.getLLVMContext(), FieldTypes, TDTypeName);
456  return TypeDescriptorType;
457  }
458 
459  llvm::Type *getImageRelativeType(llvm::Type *PtrType) {
460  if (!isImageRelative())
461  return PtrType;
462  return CGM.IntTy;
463  }
464 
465  llvm::StructType *getBaseClassDescriptorType() {
466  if (BaseClassDescriptorType)
467  return BaseClassDescriptorType;
468  llvm::Type *FieldTypes[] = {
469  getImageRelativeType(CGM.Int8PtrTy),
470  CGM.IntTy,
471  CGM.IntTy,
472  CGM.IntTy,
473  CGM.IntTy,
474  CGM.IntTy,
475  getImageRelativeType(getClassHierarchyDescriptorType()->getPointerTo()),
476  };
477  BaseClassDescriptorType = llvm::StructType::create(
478  CGM.getLLVMContext(), FieldTypes, "rtti.BaseClassDescriptor");
479  return BaseClassDescriptorType;
480  }
481 
482  llvm::StructType *getClassHierarchyDescriptorType() {
483  if (ClassHierarchyDescriptorType)
484  return ClassHierarchyDescriptorType;
485  // Forward-declare RTTIClassHierarchyDescriptor to break a cycle.
486  ClassHierarchyDescriptorType = llvm::StructType::create(
487  CGM.getLLVMContext(), "rtti.ClassHierarchyDescriptor");
488  llvm::Type *FieldTypes[] = {
489  CGM.IntTy,
490  CGM.IntTy,
491  CGM.IntTy,
492  getImageRelativeType(
493  getBaseClassDescriptorType()->getPointerTo()->getPointerTo()),
494  };
495  ClassHierarchyDescriptorType->setBody(FieldTypes);
496  return ClassHierarchyDescriptorType;
497  }
498 
499  llvm::StructType *getCompleteObjectLocatorType() {
500  if (CompleteObjectLocatorType)
501  return CompleteObjectLocatorType;
502  CompleteObjectLocatorType = llvm::StructType::create(
503  CGM.getLLVMContext(), "rtti.CompleteObjectLocator");
504  llvm::Type *FieldTypes[] = {
505  CGM.IntTy,
506  CGM.IntTy,
507  CGM.IntTy,
508  getImageRelativeType(CGM.Int8PtrTy),
509  getImageRelativeType(getClassHierarchyDescriptorType()->getPointerTo()),
510  getImageRelativeType(CompleteObjectLocatorType),
511  };
512  llvm::ArrayRef<llvm::Type *> FieldTypesRef(FieldTypes);
513  if (!isImageRelative())
514  FieldTypesRef = FieldTypesRef.drop_back();
515  CompleteObjectLocatorType->setBody(FieldTypesRef);
516  return CompleteObjectLocatorType;
517  }
518 
519  llvm::GlobalVariable *getImageBase() {
520  StringRef Name = "__ImageBase";
521  if (llvm::GlobalVariable *GV = CGM.getModule().getNamedGlobal(Name))
522  return GV;
523 
524  auto *GV = new llvm::GlobalVariable(CGM.getModule(), CGM.Int8Ty,
525  /*isConstant=*/true,
527  /*Initializer=*/nullptr, Name);
528  CGM.setDSOLocal(GV);
529  return GV;
530  }
531 
532  llvm::Constant *getImageRelativeConstant(llvm::Constant *PtrVal) {
533  if (!isImageRelative())
534  return PtrVal;
535 
536  if (PtrVal->isNullValue())
537  return llvm::Constant::getNullValue(CGM.IntTy);
538 
539  llvm::Constant *ImageBaseAsInt =
540  llvm::ConstantExpr::getPtrToInt(getImageBase(), CGM.IntPtrTy);
541  llvm::Constant *PtrValAsInt =
542  llvm::ConstantExpr::getPtrToInt(PtrVal, CGM.IntPtrTy);
543  llvm::Constant *Diff =
544  llvm::ConstantExpr::getSub(PtrValAsInt, ImageBaseAsInt,
545  /*HasNUW=*/true, /*HasNSW=*/true);
546  return llvm::ConstantExpr::getTrunc(Diff, CGM.IntTy);
547  }
548 
549 private:
550  MicrosoftMangleContext &getMangleContext() {
551  return cast<MicrosoftMangleContext>(CodeGen::CGCXXABI::getMangleContext());
552  }
553 
554  llvm::Constant *getZeroInt() {
555  return llvm::ConstantInt::get(CGM.IntTy, 0);
556  }
557 
558  llvm::Constant *getAllOnesInt() {
559  return llvm::Constant::getAllOnesValue(CGM.IntTy);
560  }
561 
562  CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD) override;
563 
564  void
565  GetNullMemberPointerFields(const MemberPointerType *MPT,
567 
568  /// Shared code for virtual base adjustment. Returns the offset from
569  /// the vbptr to the virtual base. Optionally returns the address of the
570  /// vbptr itself.
571  llvm::Value *GetVBaseOffsetFromVBPtr(CodeGenFunction &CGF,
572  Address Base,
573  llvm::Value *VBPtrOffset,
574  llvm::Value *VBTableOffset,
575  llvm::Value **VBPtr = nullptr);
576 
577  llvm::Value *GetVBaseOffsetFromVBPtr(CodeGenFunction &CGF,
578  Address Base,
579  int32_t VBPtrOffset,
580  int32_t VBTableOffset,
581  llvm::Value **VBPtr = nullptr) {
582  assert(VBTableOffset % 4 == 0 && "should be byte offset into table of i32s");
583  llvm::Value *VBPOffset = llvm::ConstantInt::get(CGM.IntTy, VBPtrOffset),
584  *VBTOffset = llvm::ConstantInt::get(CGM.IntTy, VBTableOffset);
585  return GetVBaseOffsetFromVBPtr(CGF, Base, VBPOffset, VBTOffset, VBPtr);
586  }
587 
588  std::tuple<Address, llvm::Value *, const CXXRecordDecl *>
589  performBaseAdjustment(CodeGenFunction &CGF, Address Value,
590  QualType SrcRecordTy);
591 
592  /// Performs a full virtual base adjustment. Used to dereference
593  /// pointers to members of virtual bases.
594  llvm::Value *AdjustVirtualBase(CodeGenFunction &CGF, const Expr *E,
595  const CXXRecordDecl *RD, Address Base,
596  llvm::Value *VirtualBaseAdjustmentOffset,
597  llvm::Value *VBPtrOffset /* optional */);
598 
599  /// Emits a full member pointer with the fields common to data and
600  /// function member pointers.
601  llvm::Constant *EmitFullMemberPointer(llvm::Constant *FirstField,
602  bool IsMemberFunction,
603  const CXXRecordDecl *RD,
604  CharUnits NonVirtualBaseAdjustment,
605  unsigned VBTableIndex);
606 
607  bool MemberPointerConstantIsNull(const MemberPointerType *MPT,
608  llvm::Constant *MP);
609 
610  /// - Initialize all vbptrs of 'this' with RD as the complete type.
611  void EmitVBPtrStores(CodeGenFunction &CGF, const CXXRecordDecl *RD);
612 
613  /// Caching wrapper around VBTableBuilder::enumerateVBTables().
614  const VBTableGlobals &enumerateVBTables(const CXXRecordDecl *RD);
615 
616  /// Generate a thunk for calling a virtual member function MD.
617  llvm::Function *EmitVirtualMemPtrThunk(const CXXMethodDecl *MD,
618  const MethodVFTableLocation &ML);
619 
620 public:
621  llvm::Type *ConvertMemberPointerType(const MemberPointerType *MPT) override;
622 
623  bool isZeroInitializable(const MemberPointerType *MPT) override;
624 
625  bool isMemberPointerConvertible(const MemberPointerType *MPT) const override {
626  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
627  return RD->hasAttr<MSInheritanceAttr>();
628  }
629 
630  llvm::Constant *EmitNullMemberPointer(const MemberPointerType *MPT) override;
631 
632  llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
633  CharUnits offset) override;
634  llvm::Constant *EmitMemberFunctionPointer(const CXXMethodDecl *MD) override;
635  llvm::Constant *EmitMemberPointer(const APValue &MP, QualType MPT) override;
636 
637  llvm::Value *EmitMemberPointerComparison(CodeGenFunction &CGF,
638  llvm::Value *L,
639  llvm::Value *R,
640  const MemberPointerType *MPT,
641  bool Inequality) override;
642 
643  llvm::Value *EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
644  llvm::Value *MemPtr,
645  const MemberPointerType *MPT) override;
646 
647  llvm::Value *
648  EmitMemberDataPointerAddress(CodeGenFunction &CGF, const Expr *E,
649  Address Base, llvm::Value *MemPtr,
650  const MemberPointerType *MPT) override;
651 
652  llvm::Value *EmitNonNullMemberPointerConversion(
653  const MemberPointerType *SrcTy, const MemberPointerType *DstTy,
656  CGBuilderTy &Builder);
657 
658  llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
659  const CastExpr *E,
660  llvm::Value *Src) override;
661 
662  llvm::Constant *EmitMemberPointerConversion(const CastExpr *E,
663  llvm::Constant *Src) override;
664 
665  llvm::Constant *EmitMemberPointerConversion(
666  const MemberPointerType *SrcTy, const MemberPointerType *DstTy,
668  CastExpr::path_const_iterator PathEnd, llvm::Constant *Src);
669 
670  CGCallee
671  EmitLoadOfMemberFunctionPointer(CodeGenFunction &CGF, const Expr *E,
672  Address This, llvm::Value *&ThisPtrForCall,
673  llvm::Value *MemPtr,
674  const MemberPointerType *MPT) override;
675 
676  void emitCXXStructor(GlobalDecl GD) override;
677 
678  llvm::StructType *getCatchableTypeType() {
679  if (CatchableTypeType)
680  return CatchableTypeType;
681  llvm::Type *FieldTypes[] = {
682  CGM.IntTy, // Flags
683  getImageRelativeType(CGM.Int8PtrTy), // TypeDescriptor
684  CGM.IntTy, // NonVirtualAdjustment
685  CGM.IntTy, // OffsetToVBPtr
686  CGM.IntTy, // VBTableIndex
687  CGM.IntTy, // Size
688  getImageRelativeType(CGM.Int8PtrTy) // CopyCtor
689  };
690  CatchableTypeType = llvm::StructType::create(
691  CGM.getLLVMContext(), FieldTypes, "eh.CatchableType");
692  return CatchableTypeType;
693  }
694 
695  llvm::StructType *getCatchableTypeArrayType(uint32_t NumEntries) {
696  llvm::StructType *&CatchableTypeArrayType =
697  CatchableTypeArrayTypeMap[NumEntries];
698  if (CatchableTypeArrayType)
699  return CatchableTypeArrayType;
700 
701  llvm::SmallString<23> CTATypeName("eh.CatchableTypeArray.");
702  CTATypeName += llvm::utostr(NumEntries);
703  llvm::Type *CTType =
704  getImageRelativeType(getCatchableTypeType()->getPointerTo());
705  llvm::Type *FieldTypes[] = {
706  CGM.IntTy, // NumEntries
707  llvm::ArrayType::get(CTType, NumEntries) // CatchableTypes
708  };
709  CatchableTypeArrayType =
710  llvm::StructType::create(CGM.getLLVMContext(), FieldTypes, CTATypeName);
711  return CatchableTypeArrayType;
712  }
713 
714  llvm::StructType *getThrowInfoType() {
715  if (ThrowInfoType)
716  return ThrowInfoType;
717  llvm::Type *FieldTypes[] = {
718  CGM.IntTy, // Flags
719  getImageRelativeType(CGM.Int8PtrTy), // CleanupFn
720  getImageRelativeType(CGM.Int8PtrTy), // ForwardCompat
721  getImageRelativeType(CGM.Int8PtrTy) // CatchableTypeArray
722  };
723  ThrowInfoType = llvm::StructType::create(CGM.getLLVMContext(), FieldTypes,
724  "eh.ThrowInfo");
725  return ThrowInfoType;
726  }
727 
728  llvm::FunctionCallee getThrowFn() {
729  // _CxxThrowException is passed an exception object and a ThrowInfo object
730  // which describes the exception.
731  llvm::Type *Args[] = {CGM.Int8PtrTy, getThrowInfoType()->getPointerTo()};
732  llvm::FunctionType *FTy =
733  llvm::FunctionType::get(CGM.VoidTy, Args, /*IsVarArgs=*/false);
734  llvm::FunctionCallee Throw =
735  CGM.CreateRuntimeFunction(FTy, "_CxxThrowException");
736  // _CxxThrowException is stdcall on 32-bit x86 platforms.
737  if (CGM.getTarget().getTriple().getArch() == llvm::Triple::x86) {
738  if (auto *Fn = dyn_cast<llvm::Function>(Throw.getCallee()))
739  Fn->setCallingConv(llvm::CallingConv::X86_StdCall);
740  }
741  return Throw;
742  }
743 
744  llvm::Function *getAddrOfCXXCtorClosure(const CXXConstructorDecl *CD,
745  CXXCtorType CT);
746 
747  llvm::Constant *getCatchableType(QualType T,
748  uint32_t NVOffset = 0,
749  int32_t VBPtrOffset = -1,
750  uint32_t VBIndex = 0);
751 
752  llvm::GlobalVariable *getCatchableTypeArray(QualType T);
753 
754  llvm::GlobalVariable *getThrowInfo(QualType T) override;
755 
756  std::pair<llvm::Value *, const CXXRecordDecl *>
757  LoadVTablePtr(CodeGenFunction &CGF, Address This,
758  const CXXRecordDecl *RD) override;
759 
760 private:
761  typedef std::pair<const CXXRecordDecl *, CharUnits> VFTableIdTy;
762  typedef llvm::DenseMap<VFTableIdTy, llvm::GlobalVariable *> VTablesMapTy;
763  typedef llvm::DenseMap<VFTableIdTy, llvm::GlobalValue *> VFTablesMapTy;
764  /// All the vftables that have been referenced.
765  VFTablesMapTy VFTablesMap;
766  VTablesMapTy VTablesMap;
767 
768  /// This set holds the record decls we've deferred vtable emission for.
769  llvm::SmallPtrSet<const CXXRecordDecl *, 4> DeferredVFTables;
770 
771 
772  /// All the vbtables which have been referenced.
773  llvm::DenseMap<const CXXRecordDecl *, VBTableGlobals> VBTablesMap;
774 
775  /// Info on the global variable used to guard initialization of static locals.
776  /// The BitIndex field is only used for externally invisible declarations.
777  struct GuardInfo {
778  GuardInfo() : Guard(nullptr), BitIndex(0) {}
779  llvm::GlobalVariable *Guard;
780  unsigned BitIndex;
781  };
782 
783  /// Map from DeclContext to the current guard variable. We assume that the
784  /// AST is visited in source code order.
785  llvm::DenseMap<const DeclContext *, GuardInfo> GuardVariableMap;
786  llvm::DenseMap<const DeclContext *, GuardInfo> ThreadLocalGuardVariableMap;
787  llvm::DenseMap<const DeclContext *, unsigned> ThreadSafeGuardNumMap;
788 
789  llvm::DenseMap<size_t, llvm::StructType *> TypeDescriptorTypeMap;
790  llvm::StructType *BaseClassDescriptorType;
791  llvm::StructType *ClassHierarchyDescriptorType;
792  llvm::StructType *CompleteObjectLocatorType;
793 
794  llvm::DenseMap<QualType, llvm::GlobalVariable *> CatchableTypeArrays;
795 
796  llvm::StructType *CatchableTypeType;
797  llvm::DenseMap<uint32_t, llvm::StructType *> CatchableTypeArrayTypeMap;
798  llvm::StructType *ThrowInfoType;
799 };
800 
801 }
802 
805  switch (CGM.getTarget().getTriple().getArch()) {
806  default:
807  // FIXME: Implement for other architectures.
808  return RAA_Default;
809 
810  case llvm::Triple::thumb:
811  // Use the simple Itanium rules for now.
812  // FIXME: This is incompatible with MSVC for arguments with a dtor and no
813  // copy ctor.
814  return !RD->canPassInRegisters() ? RAA_Indirect : RAA_Default;
815 
816  case llvm::Triple::x86:
817  // All record arguments are passed in memory on x86. Decide whether to
818  // construct the object directly in argument memory, or to construct the
819  // argument elsewhere and copy the bytes during the call.
820 
821  // If C++ prohibits us from making a copy, construct the arguments directly
822  // into argument memory.
823  if (!RD->canPassInRegisters())
824  return RAA_DirectInMemory;
825 
826  // Otherwise, construct the argument into a temporary and copy the bytes
827  // into the outgoing argument memory.
828  return RAA_Default;
829 
830  case llvm::Triple::x86_64:
831  case llvm::Triple::aarch64:
832  return !RD->canPassInRegisters() ? RAA_Indirect : RAA_Default;
833  }
834 
835  llvm_unreachable("invalid enum");
836 }
837 
838 void MicrosoftCXXABI::emitVirtualObjectDelete(CodeGenFunction &CGF,
839  const CXXDeleteExpr *DE,
840  Address Ptr,
841  QualType ElementType,
842  const CXXDestructorDecl *Dtor) {
843  // FIXME: Provide a source location here even though there's no
844  // CXXMemberCallExpr for dtor call.
845  bool UseGlobalDelete = DE->isGlobalDelete();
846  CXXDtorType DtorType = UseGlobalDelete ? Dtor_Complete : Dtor_Deleting;
847  llvm::Value *MDThis =
848  EmitVirtualDestructorCall(CGF, Dtor, DtorType, Ptr, /*CE=*/nullptr);
849  if (UseGlobalDelete)
850  CGF.EmitDeleteCall(DE->getOperatorDelete(), MDThis, ElementType);
851 }
852 
853 void MicrosoftCXXABI::emitRethrow(CodeGenFunction &CGF, bool isNoReturn) {
854  llvm::Value *Args[] = {
855  llvm::ConstantPointerNull::get(CGM.Int8PtrTy),
856  llvm::ConstantPointerNull::get(getThrowInfoType()->getPointerTo())};
857  llvm::FunctionCallee Fn = getThrowFn();
858  if (isNoReturn)
859  CGF.EmitNoreturnRuntimeCallOrInvoke(Fn, Args);
860  else
861  CGF.EmitRuntimeCallOrInvoke(Fn, Args);
862 }
863 
864 void MicrosoftCXXABI::emitBeginCatch(CodeGenFunction &CGF,
865  const CXXCatchStmt *S) {
866  // In the MS ABI, the runtime handles the copy, and the catch handler is
867  // responsible for destruction.
868  VarDecl *CatchParam = S->getExceptionDecl();
869  llvm::BasicBlock *CatchPadBB = CGF.Builder.GetInsertBlock();
870  llvm::CatchPadInst *CPI =
871  cast<llvm::CatchPadInst>(CatchPadBB->getFirstNonPHI());
872  CGF.CurrentFuncletPad = CPI;
873 
874  // If this is a catch-all or the catch parameter is unnamed, we don't need to
875  // emit an alloca to the object.
876  if (!CatchParam || !CatchParam->getDeclName()) {
877  CGF.EHStack.pushCleanup<CatchRetScope>(NormalCleanup, CPI);
878  return;
879  }
880 
882  CPI->setArgOperand(2, var.getObjectAddress(CGF).getPointer());
883  CGF.EHStack.pushCleanup<CatchRetScope>(NormalCleanup, CPI);
884  CGF.EmitAutoVarCleanups(var);
885 }
886 
887 /// We need to perform a generic polymorphic operation (like a typeid
888 /// or a cast), which requires an object with a vfptr. Adjust the
889 /// address to point to an object with a vfptr.
890 std::tuple<Address, llvm::Value *, const CXXRecordDecl *>
891 MicrosoftCXXABI::performBaseAdjustment(CodeGenFunction &CGF, Address Value,
892  QualType SrcRecordTy) {
893  Value = CGF.Builder.CreateBitCast(Value, CGF.Int8PtrTy);
894  const CXXRecordDecl *SrcDecl = SrcRecordTy->getAsCXXRecordDecl();
895  const ASTContext &Context = getContext();
896 
897  // If the class itself has a vfptr, great. This check implicitly
898  // covers non-virtual base subobjects: a class with its own virtual
899  // functions would be a candidate to be a primary base.
900  if (Context.getASTRecordLayout(SrcDecl).hasExtendableVFPtr())
901  return std::make_tuple(Value, llvm::ConstantInt::get(CGF.Int32Ty, 0),
902  SrcDecl);
903 
904  // Okay, one of the vbases must have a vfptr, or else this isn't
905  // actually a polymorphic class.
906  const CXXRecordDecl *PolymorphicBase = nullptr;
907  for (auto &Base : SrcDecl->vbases()) {
908  const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
909  if (Context.getASTRecordLayout(BaseDecl).hasExtendableVFPtr()) {
910  PolymorphicBase = BaseDecl;
911  break;
912  }
913  }
914  assert(PolymorphicBase && "polymorphic class has no apparent vfptr?");
915 
917  GetVirtualBaseClassOffset(CGF, Value, SrcDecl, PolymorphicBase);
918  llvm::Value *Ptr = CGF.Builder.CreateInBoundsGEP(Value.getPointer(), Offset);
919  CharUnits VBaseAlign =
920  CGF.CGM.getVBaseAlignment(Value.getAlignment(), SrcDecl, PolymorphicBase);
921  return std::make_tuple(Address(Ptr, VBaseAlign), Offset, PolymorphicBase);
922 }
923 
924 bool MicrosoftCXXABI::shouldTypeidBeNullChecked(bool IsDeref,
925  QualType SrcRecordTy) {
926  const CXXRecordDecl *SrcDecl = SrcRecordTy->getAsCXXRecordDecl();
927  return IsDeref &&
928  !getContext().getASTRecordLayout(SrcDecl).hasExtendableVFPtr();
929 }
930 
931 static llvm::CallBase *emitRTtypeidCall(CodeGenFunction &CGF,
932  llvm::Value *Argument) {
933  llvm::Type *ArgTypes[] = {CGF.Int8PtrTy};
934  llvm::FunctionType *FTy =
935  llvm::FunctionType::get(CGF.Int8PtrTy, ArgTypes, false);
936  llvm::Value *Args[] = {Argument};
937  llvm::FunctionCallee Fn = CGF.CGM.CreateRuntimeFunction(FTy, "__RTtypeid");
938  return CGF.EmitRuntimeCallOrInvoke(Fn, Args);
939 }
940 
941 void MicrosoftCXXABI::EmitBadTypeidCall(CodeGenFunction &CGF) {
942  llvm::CallBase *Call =
943  emitRTtypeidCall(CGF, llvm::Constant::getNullValue(CGM.VoidPtrTy));
944  Call->setDoesNotReturn();
945  CGF.Builder.CreateUnreachable();
946 }
947 
948 llvm::Value *MicrosoftCXXABI::EmitTypeid(CodeGenFunction &CGF,
949  QualType SrcRecordTy,
950  Address ThisPtr,
951  llvm::Type *StdTypeInfoPtrTy) {
952  std::tie(ThisPtr, std::ignore, std::ignore) =
953  performBaseAdjustment(CGF, ThisPtr, SrcRecordTy);
954  llvm::CallBase *Typeid = emitRTtypeidCall(CGF, ThisPtr.getPointer());
955  return CGF.Builder.CreateBitCast(Typeid, StdTypeInfoPtrTy);
956 }
957 
958 bool MicrosoftCXXABI::shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
959  QualType SrcRecordTy) {
960  const CXXRecordDecl *SrcDecl = SrcRecordTy->getAsCXXRecordDecl();
961  return SrcIsPtr &&
962  !getContext().getASTRecordLayout(SrcDecl).hasExtendableVFPtr();
963 }
964 
965 llvm::Value *MicrosoftCXXABI::EmitDynamicCastCall(
966  CodeGenFunction &CGF, Address This, QualType SrcRecordTy,
967  QualType DestTy, QualType DestRecordTy, llvm::BasicBlock *CastEnd) {
968  llvm::Type *DestLTy = CGF.ConvertType(DestTy);
969 
970  llvm::Value *SrcRTTI =
972  llvm::Value *DestRTTI =
973  CGF.CGM.GetAddrOfRTTIDescriptor(DestRecordTy.getUnqualifiedType());
974 
976  std::tie(This, Offset, std::ignore) =
977  performBaseAdjustment(CGF, This, SrcRecordTy);
978  llvm::Value *ThisPtr = This.getPointer();
979  Offset = CGF.Builder.CreateTrunc(Offset, CGF.Int32Ty);
980 
981  // PVOID __RTDynamicCast(
982  // PVOID inptr,
983  // LONG VfDelta,
984  // PVOID SrcType,
985  // PVOID TargetType,
986  // BOOL isReference)
987  llvm::Type *ArgTypes[] = {CGF.Int8PtrTy, CGF.Int32Ty, CGF.Int8PtrTy,
988  CGF.Int8PtrTy, CGF.Int32Ty};
989  llvm::FunctionCallee Function = CGF.CGM.CreateRuntimeFunction(
990  llvm::FunctionType::get(CGF.Int8PtrTy, ArgTypes, false),
991  "__RTDynamicCast");
992  llvm::Value *Args[] = {
993  ThisPtr, Offset, SrcRTTI, DestRTTI,
994  llvm::ConstantInt::get(CGF.Int32Ty, DestTy->isReferenceType())};
995  ThisPtr = CGF.EmitRuntimeCallOrInvoke(Function, Args);
996  return CGF.Builder.CreateBitCast(ThisPtr, DestLTy);
997 }
998 
999 llvm::Value *
1000 MicrosoftCXXABI::EmitDynamicCastToVoid(CodeGenFunction &CGF, Address Value,
1001  QualType SrcRecordTy,
1002  QualType DestTy) {
1003  std::tie(Value, std::ignore, std::ignore) =
1004  performBaseAdjustment(CGF, Value, SrcRecordTy);
1005 
1006  // PVOID __RTCastToVoid(
1007  // PVOID inptr)
1008  llvm::Type *ArgTypes[] = {CGF.Int8PtrTy};
1009  llvm::FunctionCallee Function = CGF.CGM.CreateRuntimeFunction(
1010  llvm::FunctionType::get(CGF.Int8PtrTy, ArgTypes, false),
1011  "__RTCastToVoid");
1012  llvm::Value *Args[] = {Value.getPointer()};
1013  return CGF.EmitRuntimeCall(Function, Args);
1014 }
1015 
1016 bool MicrosoftCXXABI::EmitBadCastCall(CodeGenFunction &CGF) {
1017  return false;
1018 }
1019 
1020 llvm::Value *MicrosoftCXXABI::GetVirtualBaseClassOffset(
1021  CodeGenFunction &CGF, Address This, const CXXRecordDecl *ClassDecl,
1022  const CXXRecordDecl *BaseClassDecl) {
1023  const ASTContext &Context = getContext();
1024  int64_t VBPtrChars =
1025  Context.getASTRecordLayout(ClassDecl).getVBPtrOffset().getQuantity();
1026  llvm::Value *VBPtrOffset = llvm::ConstantInt::get(CGM.PtrDiffTy, VBPtrChars);
1027  CharUnits IntSize = Context.getTypeSizeInChars(Context.IntTy);
1028  CharUnits VBTableChars =
1029  IntSize *
1030  CGM.getMicrosoftVTableContext().getVBTableIndex(ClassDecl, BaseClassDecl);
1031  llvm::Value *VBTableOffset =
1032  llvm::ConstantInt::get(CGM.IntTy, VBTableChars.getQuantity());
1033 
1034  llvm::Value *VBPtrToNewBase =
1035  GetVBaseOffsetFromVBPtr(CGF, This, VBPtrOffset, VBTableOffset);
1036  VBPtrToNewBase =
1037  CGF.Builder.CreateSExtOrBitCast(VBPtrToNewBase, CGM.PtrDiffTy);
1038  return CGF.Builder.CreateNSWAdd(VBPtrOffset, VBPtrToNewBase);
1039 }
1040 
1041 bool MicrosoftCXXABI::HasThisReturn(GlobalDecl GD) const {
1042  return isa<CXXConstructorDecl>(GD.getDecl());
1043 }
1044 
1045 static bool isDeletingDtor(GlobalDecl GD) {
1046  return isa<CXXDestructorDecl>(GD.getDecl()) &&
1047  GD.getDtorType() == Dtor_Deleting;
1048 }
1049 
1050 bool MicrosoftCXXABI::hasMostDerivedReturn(GlobalDecl GD) const {
1051  return isDeletingDtor(GD);
1052 }
1053 
1054 static bool IsSizeGreaterThan128(const CXXRecordDecl *RD) {
1055  return RD->getASTContext().getTypeSize(RD->getTypeForDecl()) > 128;
1056 }
1057 
1059  // For AArch64, we use the C++14 definition of an aggregate, so we also
1060  // check for:
1061  // No private or protected non static data members.
1062  // No base classes
1063  // No virtual functions
1064  // Additionally, we need to ensure that there is a trivial copy assignment
1065  // operator, a trivial destructor and no user-provided constructors.
1066  if (RD->hasProtectedFields() || RD->hasPrivateFields())
1067  return true;
1068  if (RD->getNumBases() > 0)
1069  return true;
1070  if (RD->isPolymorphic())
1071  return true;
1072  if (RD->hasNonTrivialCopyAssignment())
1073  return true;
1074  for (const CXXConstructorDecl *Ctor : RD->ctors())
1075  if (Ctor->isUserProvided())
1076  return true;
1077  if (RD->hasNonTrivialDestructor())
1078  return true;
1079  return false;
1080 }
1081 
1083  const CXXRecordDecl *RD = FI.getReturnType()->getAsCXXRecordDecl();
1084  if (!RD)
1085  return false;
1086 
1087  bool isAArch64 = CGM.getTarget().getTriple().isAArch64();
1088  bool isSimple = !isAArch64 || !hasMicrosoftABIRestrictions(RD);
1089  bool isIndirectReturn =
1090  isAArch64 ? (!RD->canPassInRegisters() ||
1092  : !RD->isPOD();
1093  bool isInstanceMethod = FI.isInstanceMethod();
1094 
1095  if (isIndirectReturn || !isSimple || isInstanceMethod) {
1096  CharUnits Align = CGM.getContext().getTypeAlignInChars(FI.getReturnType());
1097  FI.getReturnInfo() = ABIArgInfo::getIndirect(Align, /*ByVal=*/false);
1098  FI.getReturnInfo().setSRetAfterThis(isInstanceMethod);
1099 
1100  FI.getReturnInfo().setInReg(isAArch64 &&
1101  !(isSimple && IsSizeGreaterThan128(RD)));
1102 
1103  return true;
1104  }
1105 
1106  // Otherwise, use the C ABI rules.
1107  return false;
1108 }
1109 
1110 llvm::BasicBlock *
1111 MicrosoftCXXABI::EmitCtorCompleteObjectHandler(CodeGenFunction &CGF,
1112  const CXXRecordDecl *RD) {
1113  llvm::Value *IsMostDerivedClass = getStructorImplicitParamValue(CGF);
1114  assert(IsMostDerivedClass &&
1115  "ctor for a class with virtual bases must have an implicit parameter");
1116  llvm::Value *IsCompleteObject =
1117  CGF.Builder.CreateIsNotNull(IsMostDerivedClass, "is_complete_object");
1118 
1119  llvm::BasicBlock *CallVbaseCtorsBB = CGF.createBasicBlock("ctor.init_vbases");
1120  llvm::BasicBlock *SkipVbaseCtorsBB = CGF.createBasicBlock("ctor.skip_vbases");
1121  CGF.Builder.CreateCondBr(IsCompleteObject,
1122  CallVbaseCtorsBB, SkipVbaseCtorsBB);
1123 
1124  CGF.EmitBlock(CallVbaseCtorsBB);
1125 
1126  // Fill in the vbtable pointers here.
1127  EmitVBPtrStores(CGF, RD);
1128 
1129  // CGF will put the base ctor calls in this basic block for us later.
1130 
1131  return SkipVbaseCtorsBB;
1132 }
1133 
1134 llvm::BasicBlock *
1135 MicrosoftCXXABI::EmitDtorCompleteObjectHandler(CodeGenFunction &CGF) {
1136  llvm::Value *IsMostDerivedClass = getStructorImplicitParamValue(CGF);
1137  assert(IsMostDerivedClass &&
1138  "ctor for a class with virtual bases must have an implicit parameter");
1139  llvm::Value *IsCompleteObject =
1140  CGF.Builder.CreateIsNotNull(IsMostDerivedClass, "is_complete_object");
1141 
1142  llvm::BasicBlock *CallVbaseDtorsBB = CGF.createBasicBlock("Dtor.dtor_vbases");
1143  llvm::BasicBlock *SkipVbaseDtorsBB = CGF.createBasicBlock("Dtor.skip_vbases");
1144  CGF.Builder.CreateCondBr(IsCompleteObject,
1145  CallVbaseDtorsBB, SkipVbaseDtorsBB);
1146 
1147  CGF.EmitBlock(CallVbaseDtorsBB);
1148  // CGF will put the base dtor calls in this basic block for us later.
1149 
1150  return SkipVbaseDtorsBB;
1151 }
1152 
1153 void MicrosoftCXXABI::initializeHiddenVirtualInheritanceMembers(
1154  CodeGenFunction &CGF, const CXXRecordDecl *RD) {
1155  // In most cases, an override for a vbase virtual method can adjust
1156  // the "this" parameter by applying a constant offset.
1157  // However, this is not enough while a constructor or a destructor of some
1158  // class X is being executed if all the following conditions are met:
1159  // - X has virtual bases, (1)
1160  // - X overrides a virtual method M of a vbase Y, (2)
1161  // - X itself is a vbase of the most derived class.
1162  //
1163  // If (1) and (2) are true, the vtorDisp for vbase Y is a hidden member of X
1164  // which holds the extra amount of "this" adjustment we must do when we use
1165  // the X vftables (i.e. during X ctor or dtor).
1166  // Outside the ctors and dtors, the values of vtorDisps are zero.
1167 
1168  const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
1169  typedef ASTRecordLayout::VBaseOffsetsMapTy VBOffsets;
1170  const VBOffsets &VBaseMap = Layout.getVBaseOffsetsMap();
1171  CGBuilderTy &Builder = CGF.Builder;
1172 
1173  unsigned AS = getThisAddress(CGF).getAddressSpace();
1174  llvm::Value *Int8This = nullptr; // Initialize lazily.
1175 
1176  for (const CXXBaseSpecifier &S : RD->vbases()) {
1177  const CXXRecordDecl *VBase = S.getType()->getAsCXXRecordDecl();
1178  auto I = VBaseMap.find(VBase);
1179  assert(I != VBaseMap.end());
1180  if (!I->second.hasVtorDisp())
1181  continue;
1182 
1183  llvm::Value *VBaseOffset =
1184  GetVirtualBaseClassOffset(CGF, getThisAddress(CGF), RD, VBase);
1185  uint64_t ConstantVBaseOffset = I->second.VBaseOffset.getQuantity();
1186 
1187  // vtorDisp_for_vbase = vbptr[vbase_idx] - offsetof(RD, vbase).
1188  llvm::Value *VtorDispValue = Builder.CreateSub(
1189  VBaseOffset, llvm::ConstantInt::get(CGM.PtrDiffTy, ConstantVBaseOffset),
1190  "vtordisp.value");
1191  VtorDispValue = Builder.CreateTruncOrBitCast(VtorDispValue, CGF.Int32Ty);
1192 
1193  if (!Int8This)
1194  Int8This = Builder.CreateBitCast(getThisValue(CGF),
1195  CGF.Int8Ty->getPointerTo(AS));
1196  llvm::Value *VtorDispPtr = Builder.CreateInBoundsGEP(Int8This, VBaseOffset);
1197  // vtorDisp is always the 32-bits before the vbase in the class layout.
1198  VtorDispPtr = Builder.CreateConstGEP1_32(VtorDispPtr, -4);
1199  VtorDispPtr = Builder.CreateBitCast(
1200  VtorDispPtr, CGF.Int32Ty->getPointerTo(AS), "vtordisp.ptr");
1201 
1202  Builder.CreateAlignedStore(VtorDispValue, VtorDispPtr,
1204  }
1205 }
1206 
1207 static bool hasDefaultCXXMethodCC(ASTContext &Context,
1208  const CXXMethodDecl *MD) {
1209  CallingConv ExpectedCallingConv = Context.getDefaultCallingConvention(
1210  /*IsVariadic=*/false, /*IsCXXMethod=*/true);
1211  CallingConv ActualCallingConv =
1212  MD->getType()->getAs<FunctionProtoType>()->getCallConv();
1213  return ExpectedCallingConv == ActualCallingConv;
1214 }
1215 
1216 void MicrosoftCXXABI::EmitCXXConstructors(const CXXConstructorDecl *D) {
1217  // There's only one constructor type in this ABI.
1218  CGM.EmitGlobal(GlobalDecl(D, Ctor_Complete));
1219 
1220  // Exported default constructors either have a simple call-site where they use
1221  // the typical calling convention and have a single 'this' pointer for an
1222  // argument -or- they get a wrapper function which appropriately thunks to the
1223  // real default constructor. This thunk is the default constructor closure.
1224  if (D->hasAttr<DLLExportAttr>() && D->isDefaultConstructor())
1225  if (!hasDefaultCXXMethodCC(getContext(), D) || D->getNumParams() != 0) {
1226  llvm::Function *Fn = getAddrOfCXXCtorClosure(D, Ctor_DefaultClosure);
1227  Fn->setLinkage(llvm::GlobalValue::WeakODRLinkage);
1228  CGM.setGVProperties(Fn, D);
1229  }
1230 }
1231 
1232 void MicrosoftCXXABI::EmitVBPtrStores(CodeGenFunction &CGF,
1233  const CXXRecordDecl *RD) {
1234  Address This = getThisAddress(CGF);
1235  This = CGF.Builder.CreateElementBitCast(This, CGM.Int8Ty, "this.int8");
1236  const ASTContext &Context = getContext();
1237  const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1238 
1239  const VBTableGlobals &VBGlobals = enumerateVBTables(RD);
1240  for (unsigned I = 0, E = VBGlobals.VBTables->size(); I != E; ++I) {
1241  const std::unique_ptr<VPtrInfo> &VBT = (*VBGlobals.VBTables)[I];
1242  llvm::GlobalVariable *GV = VBGlobals.Globals[I];
1243  const ASTRecordLayout &SubobjectLayout =
1244  Context.getASTRecordLayout(VBT->IntroducingObject);
1245  CharUnits Offs = VBT->NonVirtualOffset;
1246  Offs += SubobjectLayout.getVBPtrOffset();
1247  if (VBT->getVBaseWithVPtr())
1248  Offs += Layout.getVBaseClassOffset(VBT->getVBaseWithVPtr());
1249  Address VBPtr = CGF.Builder.CreateConstInBoundsByteGEP(This, Offs);
1250  llvm::Value *GVPtr =
1251  CGF.Builder.CreateConstInBoundsGEP2_32(GV->getValueType(), GV, 0, 0);
1252  VBPtr = CGF.Builder.CreateElementBitCast(VBPtr, GVPtr->getType(),
1253  "vbptr." + VBT->ObjectWithVPtr->getName());
1254  CGF.Builder.CreateStore(GVPtr, VBPtr);
1255  }
1256 }
1257 
1259 MicrosoftCXXABI::buildStructorSignature(GlobalDecl GD,
1260  SmallVectorImpl<CanQualType> &ArgTys) {
1261  AddedStructorArgs Added;
1262  // TODO: 'for base' flag
1263  if (isa<CXXDestructorDecl>(GD.getDecl()) &&
1264  GD.getDtorType() == Dtor_Deleting) {
1265  // The scalar deleting destructor takes an implicit int parameter.
1266  ArgTys.push_back(getContext().IntTy);
1267  ++Added.Suffix;
1268  }
1269  auto *CD = dyn_cast<CXXConstructorDecl>(GD.getDecl());
1270  if (!CD)
1271  return Added;
1272 
1273  // All parameters are already in place except is_most_derived, which goes
1274  // after 'this' if it's variadic and last if it's not.
1275 
1276  const CXXRecordDecl *Class = CD->getParent();
1277  const FunctionProtoType *FPT = CD->getType()->castAs<FunctionProtoType>();
1278  if (Class->getNumVBases()) {
1279  if (FPT->isVariadic()) {
1280  ArgTys.insert(ArgTys.begin() + 1, getContext().IntTy);
1281  ++Added.Prefix;
1282  } else {
1283  ArgTys.push_back(getContext().IntTy);
1284  ++Added.Suffix;
1285  }
1286  }
1287 
1288  return Added;
1289 }
1290 
1291 void MicrosoftCXXABI::setCXXDestructorDLLStorage(llvm::GlobalValue *GV,
1292  const CXXDestructorDecl *Dtor,
1293  CXXDtorType DT) const {
1294  // Deleting destructor variants are never imported or exported. Give them the
1295  // default storage class.
1296  if (DT == Dtor_Deleting) {
1297  GV->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
1298  } else {
1299  const NamedDecl *ND = Dtor;
1300  CGM.setDLLImportDLLExport(GV, ND);
1301  }
1302 }
1303 
1304 llvm::GlobalValue::LinkageTypes MicrosoftCXXABI::getCXXDestructorLinkage(
1305  GVALinkage Linkage, const CXXDestructorDecl *Dtor, CXXDtorType DT) const {
1306  // Internal things are always internal, regardless of attributes. After this,
1307  // we know the thunk is externally visible.
1308  if (Linkage == GVA_Internal)
1310 
1311  switch (DT) {
1312  case Dtor_Base:
1313  // The base destructor most closely tracks the user-declared constructor, so
1314  // we delegate back to the normal declarator case.
1315  return CGM.getLLVMLinkageForDeclarator(Dtor, Linkage,
1316  /*isConstantVariable=*/false);
1317  case Dtor_Complete:
1318  // The complete destructor is like an inline function, but it may be
1319  // imported and therefore must be exported as well. This requires changing
1320  // the linkage if a DLL attribute is present.
1321  if (Dtor->hasAttr<DLLExportAttr>())
1322  return llvm::GlobalValue::WeakODRLinkage;
1323  if (Dtor->hasAttr<DLLImportAttr>())
1324  return llvm::GlobalValue::AvailableExternallyLinkage;
1325  return llvm::GlobalValue::LinkOnceODRLinkage;
1326  case Dtor_Deleting:
1327  // Deleting destructors are like inline functions. They have vague linkage
1328  // and are emitted everywhere they are used. They are internal if the class
1329  // is internal.
1330  return llvm::GlobalValue::LinkOnceODRLinkage;
1331  case Dtor_Comdat:
1332  llvm_unreachable("MS C++ ABI does not support comdat dtors");
1333  }
1334  llvm_unreachable("invalid dtor type");
1335 }
1336 
1337 void MicrosoftCXXABI::EmitCXXDestructors(const CXXDestructorDecl *D) {
1338  // The TU defining a dtor is only guaranteed to emit a base destructor. All
1339  // other destructor variants are delegating thunks.
1340  CGM.EmitGlobal(GlobalDecl(D, Dtor_Base));
1341 }
1342 
1343 CharUnits
1344 MicrosoftCXXABI::getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD) {
1345  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
1346 
1347  if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
1348  // Complete destructors take a pointer to the complete object as a
1349  // parameter, thus don't need this adjustment.
1350  if (GD.getDtorType() == Dtor_Complete)
1351  return CharUnits();
1352 
1353  // There's no Dtor_Base in vftable but it shares the this adjustment with
1354  // the deleting one, so look it up instead.
1355  GD = GlobalDecl(DD, Dtor_Deleting);
1356  }
1357 
1359  CGM.getMicrosoftVTableContext().getMethodVFTableLocation(GD);
1360  CharUnits Adjustment = ML.VFPtrOffset;
1361 
1362  // Normal virtual instance methods need to adjust from the vfptr that first
1363  // defined the virtual method to the virtual base subobject, but destructors
1364  // do not. The vector deleting destructor thunk applies this adjustment for
1365  // us if necessary.
1366  if (isa<CXXDestructorDecl>(MD))
1367  Adjustment = CharUnits::Zero();
1368 
1369  if (ML.VBase) {
1370  const ASTRecordLayout &DerivedLayout =
1371  getContext().getASTRecordLayout(MD->getParent());
1372  Adjustment += DerivedLayout.getVBaseClassOffset(ML.VBase);
1373  }
1374 
1375  return Adjustment;
1376 }
1377 
1378 Address MicrosoftCXXABI::adjustThisArgumentForVirtualFunctionCall(
1379  CodeGenFunction &CGF, GlobalDecl GD, Address This,
1380  bool VirtualCall) {
1381  if (!VirtualCall) {
1382  // If the call of a virtual function is not virtual, we just have to
1383  // compensate for the adjustment the virtual function does in its prologue.
1384  CharUnits Adjustment = getVirtualFunctionPrologueThisAdjustment(GD);
1385  if (Adjustment.isZero())
1386  return This;
1387 
1388  This = CGF.Builder.CreateElementBitCast(This, CGF.Int8Ty);
1389  assert(Adjustment.isPositive());
1390  return CGF.Builder.CreateConstByteGEP(This, Adjustment);
1391  }
1392 
1393  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
1394 
1395  GlobalDecl LookupGD = GD;
1396  if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD)) {
1397  // Complete dtors take a pointer to the complete object,
1398  // thus don't need adjustment.
1399  if (GD.getDtorType() == Dtor_Complete)
1400  return This;
1401 
1402  // There's only Dtor_Deleting in vftable but it shares the this adjustment
1403  // with the base one, so look up the deleting one instead.
1404  LookupGD = GlobalDecl(DD, Dtor_Deleting);
1405  }
1407  CGM.getMicrosoftVTableContext().getMethodVFTableLocation(LookupGD);
1408 
1409  CharUnits StaticOffset = ML.VFPtrOffset;
1410 
1411  // Base destructors expect 'this' to point to the beginning of the base
1412  // subobject, not the first vfptr that happens to contain the virtual dtor.
1413  // However, we still need to apply the virtual base adjustment.
1414  if (isa<CXXDestructorDecl>(MD) && GD.getDtorType() == Dtor_Base)
1415  StaticOffset = CharUnits::Zero();
1416 
1417  Address Result = This;
1418  if (ML.VBase) {
1419  Result = CGF.Builder.CreateElementBitCast(Result, CGF.Int8Ty);
1420 
1421  const CXXRecordDecl *Derived = MD->getParent();
1422  const CXXRecordDecl *VBase = ML.VBase;
1423  llvm::Value *VBaseOffset =
1424  GetVirtualBaseClassOffset(CGF, Result, Derived, VBase);
1425  llvm::Value *VBasePtr =
1426  CGF.Builder.CreateInBoundsGEP(Result.getPointer(), VBaseOffset);
1427  CharUnits VBaseAlign =
1428  CGF.CGM.getVBaseAlignment(Result.getAlignment(), Derived, VBase);
1429  Result = Address(VBasePtr, VBaseAlign);
1430  }
1431  if (!StaticOffset.isZero()) {
1432  assert(StaticOffset.isPositive());
1433  Result = CGF.Builder.CreateElementBitCast(Result, CGF.Int8Ty);
1434  if (ML.VBase) {
1435  // Non-virtual adjustment might result in a pointer outside the allocated
1436  // object, e.g. if the final overrider class is laid out after the virtual
1437  // base that declares a method in the most derived class.
1438  // FIXME: Update the code that emits this adjustment in thunks prologues.
1439  Result = CGF.Builder.CreateConstByteGEP(Result, StaticOffset);
1440  } else {
1441  Result = CGF.Builder.CreateConstInBoundsByteGEP(Result, StaticOffset);
1442  }
1443  }
1444  return Result;
1445 }
1446 
1447 void MicrosoftCXXABI::addImplicitStructorParams(CodeGenFunction &CGF,
1448  QualType &ResTy,
1449  FunctionArgList &Params) {
1450  ASTContext &Context = getContext();
1451  const CXXMethodDecl *MD = cast<CXXMethodDecl>(CGF.CurGD.getDecl());
1452  assert(isa<CXXConstructorDecl>(MD) || isa<CXXDestructorDecl>(MD));
1453  if (isa<CXXConstructorDecl>(MD) && MD->getParent()->getNumVBases()) {
1454  auto *IsMostDerived = ImplicitParamDecl::Create(
1455  Context, /*DC=*/nullptr, CGF.CurGD.getDecl()->getLocation(),
1456  &Context.Idents.get("is_most_derived"), Context.IntTy,
1458  // The 'most_derived' parameter goes second if the ctor is variadic and last
1459  // if it's not. Dtors can't be variadic.
1460  const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
1461  if (FPT->isVariadic())
1462  Params.insert(Params.begin() + 1, IsMostDerived);
1463  else
1464  Params.push_back(IsMostDerived);
1465  getStructorImplicitParamDecl(CGF) = IsMostDerived;
1466  } else if (isDeletingDtor(CGF.CurGD)) {
1467  auto *ShouldDelete = ImplicitParamDecl::Create(
1468  Context, /*DC=*/nullptr, CGF.CurGD.getDecl()->getLocation(),
1469  &Context.Idents.get("should_call_delete"), Context.IntTy,
1471  Params.push_back(ShouldDelete);
1472  getStructorImplicitParamDecl(CGF) = ShouldDelete;
1473  }
1474 }
1475 
1476 void MicrosoftCXXABI::EmitInstanceFunctionProlog(CodeGenFunction &CGF) {
1477  // Naked functions have no prolog.
1478  if (CGF.CurFuncDecl && CGF.CurFuncDecl->hasAttr<NakedAttr>())
1479  return;
1480 
1481  // Overridden virtual methods of non-primary bases need to adjust the incoming
1482  // 'this' pointer in the prologue. In this hierarchy, C::b will subtract
1483  // sizeof(void*) to adjust from B* to C*:
1484  // struct A { virtual void a(); };
1485  // struct B { virtual void b(); };
1486  // struct C : A, B { virtual void b(); };
1487  //
1488  // Leave the value stored in the 'this' alloca unadjusted, so that the
1489  // debugger sees the unadjusted value. Microsoft debuggers require this, and
1490  // will apply the ThisAdjustment in the method type information.
1491  // FIXME: Do something better for DWARF debuggers, which won't expect this,
1492  // without making our codegen depend on debug info settings.
1493  llvm::Value *This = loadIncomingCXXThis(CGF);
1494  const CXXMethodDecl *MD = cast<CXXMethodDecl>(CGF.CurGD.getDecl());
1495  if (!CGF.CurFuncIsThunk && MD->isVirtual()) {
1496  CharUnits Adjustment = getVirtualFunctionPrologueThisAdjustment(CGF.CurGD);
1497  if (!Adjustment.isZero()) {
1498  unsigned AS = cast<llvm::PointerType>(This->getType())->getAddressSpace();
1499  llvm::Type *charPtrTy = CGF.Int8Ty->getPointerTo(AS),
1500  *thisTy = This->getType();
1501  This = CGF.Builder.CreateBitCast(This, charPtrTy);
1502  assert(Adjustment.isPositive());
1503  This = CGF.Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, This,
1504  -Adjustment.getQuantity());
1505  This = CGF.Builder.CreateBitCast(This, thisTy, "this.adjusted");
1506  }
1507  }
1508  setCXXABIThisValue(CGF, This);
1509 
1510  // If this is a function that the ABI specifies returns 'this', initialize
1511  // the return slot to 'this' at the start of the function.
1512  //
1513  // Unlike the setting of return types, this is done within the ABI
1514  // implementation instead of by clients of CGCXXABI because:
1515  // 1) getThisValue is currently protected
1516  // 2) in theory, an ABI could implement 'this' returns some other way;
1517  // HasThisReturn only specifies a contract, not the implementation
1518  if (HasThisReturn(CGF.CurGD))
1519  CGF.Builder.CreateStore(getThisValue(CGF), CGF.ReturnValue);
1520  else if (hasMostDerivedReturn(CGF.CurGD))
1521  CGF.Builder.CreateStore(CGF.EmitCastToVoidPtr(getThisValue(CGF)),
1522  CGF.ReturnValue);
1523 
1524  if (isa<CXXConstructorDecl>(MD) && MD->getParent()->getNumVBases()) {
1525  assert(getStructorImplicitParamDecl(CGF) &&
1526  "no implicit parameter for a constructor with virtual bases?");
1527  getStructorImplicitParamValue(CGF)
1528  = CGF.Builder.CreateLoad(
1529  CGF.GetAddrOfLocalVar(getStructorImplicitParamDecl(CGF)),
1530  "is_most_derived");
1531  }
1532 
1533  if (isDeletingDtor(CGF.CurGD)) {
1534  assert(getStructorImplicitParamDecl(CGF) &&
1535  "no implicit parameter for a deleting destructor?");
1536  getStructorImplicitParamValue(CGF)
1537  = CGF.Builder.CreateLoad(
1538  CGF.GetAddrOfLocalVar(getStructorImplicitParamDecl(CGF)),
1539  "should_call_delete");
1540  }
1541 }
1542 
1543 CGCXXABI::AddedStructorArgs MicrosoftCXXABI::addImplicitConstructorArgs(
1545  bool ForVirtualBase, bool Delegating, CallArgList &Args) {
1546  assert(Type == Ctor_Complete || Type == Ctor_Base);
1547 
1548  // Check if we need a 'most_derived' parameter.
1549  if (!D->getParent()->getNumVBases())
1550  return AddedStructorArgs{};
1551 
1552  // Add the 'most_derived' argument second if we are variadic or last if not.
1553  const FunctionProtoType *FPT = D->getType()->castAs<FunctionProtoType>();
1554  llvm::Value *MostDerivedArg;
1555  if (Delegating) {
1556  MostDerivedArg = getStructorImplicitParamValue(CGF);
1557  } else {
1558  MostDerivedArg = llvm::ConstantInt::get(CGM.Int32Ty, Type == Ctor_Complete);
1559  }
1560  RValue RV = RValue::get(MostDerivedArg);
1561  if (FPT->isVariadic()) {
1562  Args.insert(Args.begin() + 1, CallArg(RV, getContext().IntTy));
1563  return AddedStructorArgs::prefix(1);
1564  }
1565  Args.add(RV, getContext().IntTy);
1566  return AddedStructorArgs::suffix(1);
1567 }
1568 
1569 void MicrosoftCXXABI::EmitDestructorCall(CodeGenFunction &CGF,
1570  const CXXDestructorDecl *DD,
1571  CXXDtorType Type, bool ForVirtualBase,
1572  bool Delegating, Address This) {
1573  // Use the base destructor variant in place of the complete destructor variant
1574  // if the class has no virtual bases. This effectively implements some of the
1575  // -mconstructor-aliases optimization, but as part of the MS C++ ABI.
1576  if (Type == Dtor_Complete && DD->getParent()->getNumVBases() == 0)
1577  Type = Dtor_Base;
1578 
1579  GlobalDecl GD(DD, Type);
1580  CGCallee Callee = CGCallee::forDirect(CGM.getAddrOfCXXStructor(GD), GD);
1581 
1582  if (DD->isVirtual()) {
1583  assert(Type != CXXDtorType::Dtor_Deleting &&
1584  "The deleting destructor should only be called via a virtual call");
1585  This = adjustThisArgumentForVirtualFunctionCall(CGF, GlobalDecl(DD, Type),
1586  This, false);
1587  }
1588 
1589  llvm::BasicBlock *BaseDtorEndBB = nullptr;
1590  if (ForVirtualBase && isa<CXXConstructorDecl>(CGF.CurCodeDecl)) {
1591  BaseDtorEndBB = EmitDtorCompleteObjectHandler(CGF);
1592  }
1593 
1594  CGF.EmitCXXDestructorCall(GD, Callee, This.getPointer(),
1595  /*ImplicitParam=*/nullptr,
1596  /*ImplicitParamTy=*/QualType(), nullptr);
1597  if (BaseDtorEndBB) {
1598  // Complete object handler should continue to be the remaining
1599  CGF.Builder.CreateBr(BaseDtorEndBB);
1600  CGF.EmitBlock(BaseDtorEndBB);
1601  }
1602 }
1603 
1604 void MicrosoftCXXABI::emitVTableTypeMetadata(const VPtrInfo &Info,
1605  const CXXRecordDecl *RD,
1606  llvm::GlobalVariable *VTable) {
1607  if (!CGM.getCodeGenOpts().LTOUnit)
1608  return;
1609 
1610  // The location of the first virtual function pointer in the virtual table,
1611  // aka the "address point" on Itanium. This is at offset 0 if RTTI is
1612  // disabled, or sizeof(void*) if RTTI is enabled.
1613  CharUnits AddressPoint =
1614  getContext().getLangOpts().RTTIData
1615  ? getContext().toCharUnitsFromBits(
1616  getContext().getTargetInfo().getPointerWidth(0))
1617  : CharUnits::Zero();
1618 
1619  if (Info.PathToIntroducingObject.empty()) {
1620  CGM.AddVTableTypeMetadata(VTable, AddressPoint, RD);
1621  return;
1622  }
1623 
1624  // Add a bitset entry for the least derived base belonging to this vftable.
1625  CGM.AddVTableTypeMetadata(VTable, AddressPoint,
1626  Info.PathToIntroducingObject.back());
1627 
1628  // Add a bitset entry for each derived class that is laid out at the same
1629  // offset as the least derived base.
1630  for (unsigned I = Info.PathToIntroducingObject.size() - 1; I != 0; --I) {
1631  const CXXRecordDecl *DerivedRD = Info.PathToIntroducingObject[I - 1];
1632  const CXXRecordDecl *BaseRD = Info.PathToIntroducingObject[I];
1633 
1634  const ASTRecordLayout &Layout =
1635  getContext().getASTRecordLayout(DerivedRD);
1636  CharUnits Offset;
1637  auto VBI = Layout.getVBaseOffsetsMap().find(BaseRD);
1638  if (VBI == Layout.getVBaseOffsetsMap().end())
1639  Offset = Layout.getBaseClassOffset(BaseRD);
1640  else
1641  Offset = VBI->second.VBaseOffset;
1642  if (!Offset.isZero())
1643  return;
1644  CGM.AddVTableTypeMetadata(VTable, AddressPoint, DerivedRD);
1645  }
1646 
1647  // Finally do the same for the most derived class.
1648  if (Info.FullOffsetInMDC.isZero())
1649  CGM.AddVTableTypeMetadata(VTable, AddressPoint, RD);
1650 }
1651 
1652 void MicrosoftCXXABI::emitVTableDefinitions(CodeGenVTables &CGVT,
1653  const CXXRecordDecl *RD) {
1654  MicrosoftVTableContext &VFTContext = CGM.getMicrosoftVTableContext();
1655  const VPtrInfoVector &VFPtrs = VFTContext.getVFPtrOffsets(RD);
1656 
1657  for (const std::unique_ptr<VPtrInfo>& Info : VFPtrs) {
1658  llvm::GlobalVariable *VTable = getAddrOfVTable(RD, Info->FullOffsetInMDC);
1659  if (VTable->hasInitializer())
1660  continue;
1661 
1662  const VTableLayout &VTLayout =
1663  VFTContext.getVFTableLayout(RD, Info->FullOffsetInMDC);
1664 
1665  llvm::Constant *RTTI = nullptr;
1666  if (any_of(VTLayout.vtable_components(),
1667  [](const VTableComponent &VTC) { return VTC.isRTTIKind(); }))
1668  RTTI = getMSCompleteObjectLocator(RD, *Info);
1669 
1670  ConstantInitBuilder Builder(CGM);
1671  auto Components = Builder.beginStruct();
1672  CGVT.createVTableInitializer(Components, VTLayout, RTTI);
1673  Components.finishAndSetAsInitializer(VTable);
1674 
1675  emitVTableTypeMetadata(*Info, RD, VTable);
1676  }
1677 }
1678 
1679 bool MicrosoftCXXABI::isVirtualOffsetNeededForVTableField(
1681  return Vptr.NearestVBase != nullptr;
1682 }
1683 
1684 llvm::Value *MicrosoftCXXABI::getVTableAddressPointInStructor(
1685  CodeGenFunction &CGF, const CXXRecordDecl *VTableClass, BaseSubobject Base,
1686  const CXXRecordDecl *NearestVBase) {
1687  llvm::Constant *VTableAddressPoint = getVTableAddressPoint(Base, VTableClass);
1688  if (!VTableAddressPoint) {
1689  assert(Base.getBase()->getNumVBases() &&
1690  !getContext().getASTRecordLayout(Base.getBase()).hasOwnVFPtr());
1691  }
1692  return VTableAddressPoint;
1693 }
1694 
1696  const CXXRecordDecl *RD, const VPtrInfo &VFPtr,
1697  SmallString<256> &Name) {
1698  llvm::raw_svector_ostream Out(Name);
1699  MangleContext.mangleCXXVFTable(RD, VFPtr.MangledPath, Out);
1700 }
1701 
1702 llvm::Constant *
1703 MicrosoftCXXABI::getVTableAddressPoint(BaseSubobject Base,
1704  const CXXRecordDecl *VTableClass) {
1705  (void)getAddrOfVTable(VTableClass, Base.getBaseOffset());
1706  VFTableIdTy ID(VTableClass, Base.getBaseOffset());
1707  return VFTablesMap[ID];
1708 }
1709 
1710 llvm::Constant *MicrosoftCXXABI::getVTableAddressPointForConstExpr(
1711  BaseSubobject Base, const CXXRecordDecl *VTableClass) {
1712  llvm::Constant *VFTable = getVTableAddressPoint(Base, VTableClass);
1713  assert(VFTable && "Couldn't find a vftable for the given base?");
1714  return VFTable;
1715 }
1716 
1717 llvm::GlobalVariable *MicrosoftCXXABI::getAddrOfVTable(const CXXRecordDecl *RD,
1718  CharUnits VPtrOffset) {
1719  // getAddrOfVTable may return 0 if asked to get an address of a vtable which
1720  // shouldn't be used in the given record type. We want to cache this result in
1721  // VFTablesMap, thus a simple zero check is not sufficient.
1722 
1723  VFTableIdTy ID(RD, VPtrOffset);
1724  VTablesMapTy::iterator I;
1725  bool Inserted;
1726  std::tie(I, Inserted) = VTablesMap.insert(std::make_pair(ID, nullptr));
1727  if (!Inserted)
1728  return I->second;
1729 
1730  llvm::GlobalVariable *&VTable = I->second;
1731 
1732  MicrosoftVTableContext &VTContext = CGM.getMicrosoftVTableContext();
1733  const VPtrInfoVector &VFPtrs = VTContext.getVFPtrOffsets(RD);
1734 
1735  if (DeferredVFTables.insert(RD).second) {
1736  // We haven't processed this record type before.
1737  // Queue up this vtable for possible deferred emission.
1738  CGM.addDeferredVTable(RD);
1739 
1740 #ifndef NDEBUG
1741  // Create all the vftables at once in order to make sure each vftable has
1742  // a unique mangled name.
1743  llvm::StringSet<> ObservedMangledNames;
1744  for (size_t J = 0, F = VFPtrs.size(); J != F; ++J) {
1745  SmallString<256> Name;
1746  mangleVFTableName(getMangleContext(), RD, *VFPtrs[J], Name);
1747  if (!ObservedMangledNames.insert(Name.str()).second)
1748  llvm_unreachable("Already saw this mangling before?");
1749  }
1750 #endif
1751  }
1752 
1753  const std::unique_ptr<VPtrInfo> *VFPtrI = std::find_if(
1754  VFPtrs.begin(), VFPtrs.end(), [&](const std::unique_ptr<VPtrInfo>& VPI) {
1755  return VPI->FullOffsetInMDC == VPtrOffset;
1756  });
1757  if (VFPtrI == VFPtrs.end()) {
1758  VFTablesMap[ID] = nullptr;
1759  return nullptr;
1760  }
1761  const std::unique_ptr<VPtrInfo> &VFPtr = *VFPtrI;
1762 
1763  SmallString<256> VFTableName;
1764  mangleVFTableName(getMangleContext(), RD, *VFPtr, VFTableName);
1765 
1766  // Classes marked __declspec(dllimport) need vftables generated on the
1767  // import-side in order to support features like constexpr. No other
1768  // translation unit relies on the emission of the local vftable, translation
1769  // units are expected to generate them as needed.
1770  //
1771  // Because of this unique behavior, we maintain this logic here instead of
1772  // getVTableLinkage.
1773  llvm::GlobalValue::LinkageTypes VFTableLinkage =
1774  RD->hasAttr<DLLImportAttr>() ? llvm::GlobalValue::LinkOnceODRLinkage
1775  : CGM.getVTableLinkage(RD);
1776  bool VFTableComesFromAnotherTU =
1777  llvm::GlobalValue::isAvailableExternallyLinkage(VFTableLinkage) ||
1778  llvm::GlobalValue::isExternalLinkage(VFTableLinkage);
1779  bool VTableAliasIsRequred =
1780  !VFTableComesFromAnotherTU && getContext().getLangOpts().RTTIData;
1781 
1782  if (llvm::GlobalValue *VFTable =
1783  CGM.getModule().getNamedGlobal(VFTableName)) {
1784  VFTablesMap[ID] = VFTable;
1785  VTable = VTableAliasIsRequred
1786  ? cast<llvm::GlobalVariable>(
1787  cast<llvm::GlobalAlias>(VFTable)->getBaseObject())
1788  : cast<llvm::GlobalVariable>(VFTable);
1789  return VTable;
1790  }
1791 
1792  const VTableLayout &VTLayout =
1793  VTContext.getVFTableLayout(RD, VFPtr->FullOffsetInMDC);
1794  llvm::GlobalValue::LinkageTypes VTableLinkage =
1795  VTableAliasIsRequred ? llvm::GlobalValue::PrivateLinkage : VFTableLinkage;
1796 
1797  StringRef VTableName = VTableAliasIsRequred ? StringRef() : VFTableName.str();
1798 
1799  llvm::Type *VTableType = CGM.getVTables().getVTableType(VTLayout);
1800 
1801  // Create a backing variable for the contents of VTable. The VTable may
1802  // or may not include space for a pointer to RTTI data.
1803  llvm::GlobalValue *VFTable;
1804  VTable = new llvm::GlobalVariable(CGM.getModule(), VTableType,
1805  /*isConstant=*/true, VTableLinkage,
1806  /*Initializer=*/nullptr, VTableName);
1807  VTable->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1808 
1809  llvm::Comdat *C = nullptr;
1810  if (!VFTableComesFromAnotherTU &&
1811  (llvm::GlobalValue::isWeakForLinker(VFTableLinkage) ||
1812  (llvm::GlobalValue::isLocalLinkage(VFTableLinkage) &&
1813  VTableAliasIsRequred)))
1814  C = CGM.getModule().getOrInsertComdat(VFTableName.str());
1815 
1816  // Only insert a pointer into the VFTable for RTTI data if we are not
1817  // importing it. We never reference the RTTI data directly so there is no
1818  // need to make room for it.
1819  if (VTableAliasIsRequred) {
1820  llvm::Value *GEPIndices[] = {llvm::ConstantInt::get(CGM.Int32Ty, 0),
1821  llvm::ConstantInt::get(CGM.Int32Ty, 0),
1822  llvm::ConstantInt::get(CGM.Int32Ty, 1)};
1823  // Create a GEP which points just after the first entry in the VFTable,
1824  // this should be the location of the first virtual method.
1825  llvm::Constant *VTableGEP = llvm::ConstantExpr::getInBoundsGetElementPtr(
1826  VTable->getValueType(), VTable, GEPIndices);
1827  if (llvm::GlobalValue::isWeakForLinker(VFTableLinkage)) {
1828  VFTableLinkage = llvm::GlobalValue::ExternalLinkage;
1829  if (C)
1830  C->setSelectionKind(llvm::Comdat::Largest);
1831  }
1832  VFTable = llvm::GlobalAlias::create(CGM.Int8PtrTy,
1833  /*AddressSpace=*/0, VFTableLinkage,
1834  VFTableName.str(), VTableGEP,
1835  &CGM.getModule());
1836  VFTable->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1837  } else {
1838  // We don't need a GlobalAlias to be a symbol for the VTable if we won't
1839  // be referencing any RTTI data.
1840  // The GlobalVariable will end up being an appropriate definition of the
1841  // VFTable.
1842  VFTable = VTable;
1843  }
1844  if (C)
1845  VTable->setComdat(C);
1846 
1847  if (RD->hasAttr<DLLExportAttr>())
1848  VFTable->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
1849 
1850  VFTablesMap[ID] = VFTable;
1851  return VTable;
1852 }
1853 
1854 CGCallee MicrosoftCXXABI::getVirtualFunctionPointer(CodeGenFunction &CGF,
1855  GlobalDecl GD,
1856  Address This,
1857  llvm::Type *Ty,
1858  SourceLocation Loc) {
1859  CGBuilderTy &Builder = CGF.Builder;
1860 
1861  Ty = Ty->getPointerTo()->getPointerTo();
1862  Address VPtr =
1863  adjustThisArgumentForVirtualFunctionCall(CGF, GD, This, true);
1864 
1865  auto *MethodDecl = cast<CXXMethodDecl>(GD.getDecl());
1866  llvm::Value *VTable = CGF.GetVTablePtr(VPtr, Ty, MethodDecl->getParent());
1867 
1868  MicrosoftVTableContext &VFTContext = CGM.getMicrosoftVTableContext();
1869  MethodVFTableLocation ML = VFTContext.getMethodVFTableLocation(GD);
1870 
1871  // Compute the identity of the most derived class whose virtual table is
1872  // located at the MethodVFTableLocation ML.
1873  auto getObjectWithVPtr = [&] {
1874  return llvm::find_if(VFTContext.getVFPtrOffsets(
1875  ML.VBase ? ML.VBase : MethodDecl->getParent()),
1876  [&](const std::unique_ptr<VPtrInfo> &Info) {
1877  return Info->FullOffsetInMDC == ML.VFPtrOffset;
1878  })
1879  ->get()
1880  ->ObjectWithVPtr;
1881  };
1882 
1883  llvm::Value *VFunc;
1884  if (CGF.ShouldEmitVTableTypeCheckedLoad(MethodDecl->getParent())) {
1885  VFunc = CGF.EmitVTableTypeCheckedLoad(
1886  getObjectWithVPtr(), VTable,
1887  ML.Index * CGM.getContext().getTargetInfo().getPointerWidth(0) / 8);
1888  } else {
1889  if (CGM.getCodeGenOpts().PrepareForLTO)
1890  CGF.EmitTypeMetadataCodeForVCall(getObjectWithVPtr(), VTable, Loc);
1891 
1892  llvm::Value *VFuncPtr =
1893  Builder.CreateConstInBoundsGEP1_64(VTable, ML.Index, "vfn");
1894  VFunc = Builder.CreateAlignedLoad(VFuncPtr, CGF.getPointerAlign());
1895  }
1896 
1897  CGCallee Callee(GD, VFunc);
1898  return Callee;
1899 }
1900 
1901 llvm::Value *MicrosoftCXXABI::EmitVirtualDestructorCall(
1902  CodeGenFunction &CGF, const CXXDestructorDecl *Dtor, CXXDtorType DtorType,
1903  Address This, const CXXMemberCallExpr *CE) {
1904  assert(CE == nullptr || CE->arg_begin() == CE->arg_end());
1905  assert(DtorType == Dtor_Deleting || DtorType == Dtor_Complete);
1906 
1907  // We have only one destructor in the vftable but can get both behaviors
1908  // by passing an implicit int parameter.
1909  GlobalDecl GD(Dtor, Dtor_Deleting);
1910  const CGFunctionInfo *FInfo =
1911  &CGM.getTypes().arrangeCXXStructorDeclaration(GD);
1912  llvm::FunctionType *Ty = CGF.CGM.getTypes().GetFunctionType(*FInfo);
1913  CGCallee Callee = CGCallee::forVirtual(CE, GD, This, Ty);
1914 
1915  ASTContext &Context = getContext();
1916  llvm::Value *ImplicitParam = llvm::ConstantInt::get(
1917  llvm::IntegerType::getInt32Ty(CGF.getLLVMContext()),
1918  DtorType == Dtor_Deleting);
1919 
1920  This = adjustThisArgumentForVirtualFunctionCall(CGF, GD, This, true);
1921  RValue RV = CGF.EmitCXXDestructorCall(GD, Callee, This.getPointer(),
1922  ImplicitParam, Context.IntTy, CE);
1923  return RV.getScalarVal();
1924 }
1925 
1926 const VBTableGlobals &
1927 MicrosoftCXXABI::enumerateVBTables(const CXXRecordDecl *RD) {
1928  // At this layer, we can key the cache off of a single class, which is much
1929  // easier than caching each vbtable individually.
1930  llvm::DenseMap<const CXXRecordDecl*, VBTableGlobals>::iterator Entry;
1931  bool Added;
1932  std::tie(Entry, Added) =
1933  VBTablesMap.insert(std::make_pair(RD, VBTableGlobals()));
1934  VBTableGlobals &VBGlobals = Entry->second;
1935  if (!Added)
1936  return VBGlobals;
1937 
1938  MicrosoftVTableContext &Context = CGM.getMicrosoftVTableContext();
1939  VBGlobals.VBTables = &Context.enumerateVBTables(RD);
1940 
1941  // Cache the globals for all vbtables so we don't have to recompute the
1942  // mangled names.
1943  llvm::GlobalVariable::LinkageTypes Linkage = CGM.getVTableLinkage(RD);
1944  for (VPtrInfoVector::const_iterator I = VBGlobals.VBTables->begin(),
1945  E = VBGlobals.VBTables->end();
1946  I != E; ++I) {
1947  VBGlobals.Globals.push_back(getAddrOfVBTable(**I, RD, Linkage));
1948  }
1949 
1950  return VBGlobals;
1951 }
1952 
1953 llvm::Function *
1954 MicrosoftCXXABI::EmitVirtualMemPtrThunk(const CXXMethodDecl *MD,
1955  const MethodVFTableLocation &ML) {
1956  assert(!isa<CXXConstructorDecl>(MD) && !isa<CXXDestructorDecl>(MD) &&
1957  "can't form pointers to ctors or virtual dtors");
1958 
1959  // Calculate the mangled name.
1960  SmallString<256> ThunkName;
1961  llvm::raw_svector_ostream Out(ThunkName);
1962  getMangleContext().mangleVirtualMemPtrThunk(MD, ML, Out);
1963 
1964  // If the thunk has been generated previously, just return it.
1965  if (llvm::GlobalValue *GV = CGM.getModule().getNamedValue(ThunkName))
1966  return cast<llvm::Function>(GV);
1967 
1968  // Create the llvm::Function.
1969  const CGFunctionInfo &FnInfo =
1970  CGM.getTypes().arrangeUnprototypedMustTailThunk(MD);
1971  llvm::FunctionType *ThunkTy = CGM.getTypes().GetFunctionType(FnInfo);
1972  llvm::Function *ThunkFn =
1974  ThunkName.str(), &CGM.getModule());
1975  assert(ThunkFn->getName() == ThunkName && "name was uniqued!");
1976 
1977  ThunkFn->setLinkage(MD->isExternallyVisible()
1978  ? llvm::GlobalValue::LinkOnceODRLinkage
1980  if (MD->isExternallyVisible())
1981  ThunkFn->setComdat(CGM.getModule().getOrInsertComdat(ThunkFn->getName()));
1982 
1983  CGM.SetLLVMFunctionAttributes(MD, FnInfo, ThunkFn);
1984  CGM.SetLLVMFunctionAttributesForDefinition(MD, ThunkFn);
1985 
1986  // Add the "thunk" attribute so that LLVM knows that the return type is
1987  // meaningless. These thunks can be used to call functions with differing
1988  // return types, and the caller is required to cast the prototype
1989  // appropriately to extract the correct value.
1990  ThunkFn->addFnAttr("thunk");
1991 
1992  // These thunks can be compared, so they are not unnamed.
1993  ThunkFn->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::None);
1994 
1995  // Start codegen.
1996  CodeGenFunction CGF(CGM);
1997  CGF.CurGD = GlobalDecl(MD);
1998  CGF.CurFuncIsThunk = true;
1999 
2000  // Build FunctionArgs, but only include the implicit 'this' parameter
2001  // declaration.
2002  FunctionArgList FunctionArgs;
2003  buildThisParam(CGF, FunctionArgs);
2004 
2005  // Start defining the function.
2006  CGF.StartFunction(GlobalDecl(), FnInfo.getReturnType(), ThunkFn, FnInfo,
2007  FunctionArgs, MD->getLocation(), SourceLocation());
2008  setCXXABIThisValue(CGF, loadIncomingCXXThis(CGF));
2009 
2010  // Load the vfptr and then callee from the vftable. The callee should have
2011  // adjusted 'this' so that the vfptr is at offset zero.
2012  llvm::Value *VTable = CGF.GetVTablePtr(
2013  getThisAddress(CGF), ThunkTy->getPointerTo()->getPointerTo(), MD->getParent());
2014 
2015  llvm::Value *VFuncPtr =
2016  CGF.Builder.CreateConstInBoundsGEP1_64(VTable, ML.Index, "vfn");
2017  llvm::Value *Callee =
2018  CGF.Builder.CreateAlignedLoad(VFuncPtr, CGF.getPointerAlign());
2019 
2020  CGF.EmitMustTailThunk(MD, getThisValue(CGF), {ThunkTy, Callee});
2021 
2022  return ThunkFn;
2023 }
2024 
2025 void MicrosoftCXXABI::emitVirtualInheritanceTables(const CXXRecordDecl *RD) {
2026  const VBTableGlobals &VBGlobals = enumerateVBTables(RD);
2027  for (unsigned I = 0, E = VBGlobals.VBTables->size(); I != E; ++I) {
2028  const std::unique_ptr<VPtrInfo>& VBT = (*VBGlobals.VBTables)[I];
2029  llvm::GlobalVariable *GV = VBGlobals.Globals[I];
2030  if (GV->isDeclaration())
2031  emitVBTableDefinition(*VBT, RD, GV);
2032  }
2033 }
2034 
2035 llvm::GlobalVariable *
2036 MicrosoftCXXABI::getAddrOfVBTable(const VPtrInfo &VBT, const CXXRecordDecl *RD,
2037  llvm::GlobalVariable::LinkageTypes Linkage) {
2038  SmallString<256> OutName;
2039  llvm::raw_svector_ostream Out(OutName);
2040  getMangleContext().mangleCXXVBTable(RD, VBT.MangledPath, Out);
2041  StringRef Name = OutName.str();
2042 
2043  llvm::ArrayType *VBTableType =
2044  llvm::ArrayType::get(CGM.IntTy, 1 + VBT.ObjectWithVPtr->getNumVBases());
2045 
2046  assert(!CGM.getModule().getNamedGlobal(Name) &&
2047  "vbtable with this name already exists: mangling bug?");
2048  CharUnits Alignment =
2049  CGM.getContext().getTypeAlignInChars(CGM.getContext().IntTy);
2050  llvm::GlobalVariable *GV = CGM.CreateOrReplaceCXXRuntimeVariable(
2051  Name, VBTableType, Linkage, Alignment.getQuantity());
2052  GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
2053 
2054  if (RD->hasAttr<DLLImportAttr>())
2055  GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
2056  else if (RD->hasAttr<DLLExportAttr>())
2057  GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
2058 
2059  if (!GV->hasExternalLinkage())
2060  emitVBTableDefinition(VBT, RD, GV);
2061 
2062  return GV;
2063 }
2064 
2065 void MicrosoftCXXABI::emitVBTableDefinition(const VPtrInfo &VBT,
2066  const CXXRecordDecl *RD,
2067  llvm::GlobalVariable *GV) const {
2068  const CXXRecordDecl *ObjectWithVPtr = VBT.ObjectWithVPtr;
2069 
2070  assert(RD->getNumVBases() && ObjectWithVPtr->getNumVBases() &&
2071  "should only emit vbtables for classes with vbtables");
2072 
2073  const ASTRecordLayout &BaseLayout =
2074  getContext().getASTRecordLayout(VBT.IntroducingObject);
2075  const ASTRecordLayout &DerivedLayout = getContext().getASTRecordLayout(RD);
2076 
2077  SmallVector<llvm::Constant *, 4> Offsets(1 + ObjectWithVPtr->getNumVBases(),
2078  nullptr);
2079 
2080  // The offset from ObjectWithVPtr's vbptr to itself always leads.
2081  CharUnits VBPtrOffset = BaseLayout.getVBPtrOffset();
2082  Offsets[0] = llvm::ConstantInt::get(CGM.IntTy, -VBPtrOffset.getQuantity());
2083 
2084  MicrosoftVTableContext &Context = CGM.getMicrosoftVTableContext();
2085  for (const auto &I : ObjectWithVPtr->vbases()) {
2086  const CXXRecordDecl *VBase = I.getType()->getAsCXXRecordDecl();
2087  CharUnits Offset = DerivedLayout.getVBaseClassOffset(VBase);
2088  assert(!Offset.isNegative());
2089 
2090  // Make it relative to the subobject vbptr.
2091  CharUnits CompleteVBPtrOffset = VBT.NonVirtualOffset + VBPtrOffset;
2092  if (VBT.getVBaseWithVPtr())
2093  CompleteVBPtrOffset +=
2094  DerivedLayout.getVBaseClassOffset(VBT.getVBaseWithVPtr());
2095  Offset -= CompleteVBPtrOffset;
2096 
2097  unsigned VBIndex = Context.getVBTableIndex(ObjectWithVPtr, VBase);
2098  assert(Offsets[VBIndex] == nullptr && "The same vbindex seen twice?");
2099  Offsets[VBIndex] = llvm::ConstantInt::get(CGM.IntTy, Offset.getQuantity());
2100  }
2101 
2102  assert(Offsets.size() ==
2103  cast<llvm::ArrayType>(cast<llvm::PointerType>(GV->getType())
2104  ->getElementType())->getNumElements());
2105  llvm::ArrayType *VBTableType =
2106  llvm::ArrayType::get(CGM.IntTy, Offsets.size());
2107  llvm::Constant *Init = llvm::ConstantArray::get(VBTableType, Offsets);
2108  GV->setInitializer(Init);
2109 
2110  if (RD->hasAttr<DLLImportAttr>())
2111  GV->setLinkage(llvm::GlobalVariable::AvailableExternallyLinkage);
2112 }
2113 
2114 llvm::Value *MicrosoftCXXABI::performThisAdjustment(CodeGenFunction &CGF,
2115  Address This,
2116  const ThisAdjustment &TA) {
2117  if (TA.isEmpty())
2118  return This.getPointer();
2119 
2120  This = CGF.Builder.CreateElementBitCast(This, CGF.Int8Ty);
2121 
2122  llvm::Value *V;
2123  if (TA.Virtual.isEmpty()) {
2124  V = This.getPointer();
2125  } else {
2126  assert(TA.Virtual.Microsoft.VtordispOffset < 0);
2127  // Adjust the this argument based on the vtordisp value.
2128  Address VtorDispPtr =
2131  VtorDispPtr = CGF.Builder.CreateElementBitCast(VtorDispPtr, CGF.Int32Ty);
2132  llvm::Value *VtorDisp = CGF.Builder.CreateLoad(VtorDispPtr, "vtordisp");
2133  V = CGF.Builder.CreateGEP(This.getPointer(),
2134  CGF.Builder.CreateNeg(VtorDisp));
2135 
2136  // Unfortunately, having applied the vtordisp means that we no
2137  // longer really have a known alignment for the vbptr step.
2138  // We'll assume the vbptr is pointer-aligned.
2139 
2140  if (TA.Virtual.Microsoft.VBPtrOffset) {
2141  // If the final overrider is defined in a virtual base other than the one
2142  // that holds the vfptr, we have to use a vtordispex thunk which looks up
2143  // the vbtable of the derived class.
2144  assert(TA.Virtual.Microsoft.VBPtrOffset > 0);
2145  assert(TA.Virtual.Microsoft.VBOffsetOffset >= 0);
2146  llvm::Value *VBPtr;
2147  llvm::Value *VBaseOffset =
2148  GetVBaseOffsetFromVBPtr(CGF, Address(V, CGF.getPointerAlign()),
2150  TA.Virtual.Microsoft.VBOffsetOffset, &VBPtr);
2151  V = CGF.Builder.CreateInBoundsGEP(VBPtr, VBaseOffset);
2152  }
2153  }
2154 
2155  if (TA.NonVirtual) {
2156  // Non-virtual adjustment might result in a pointer outside the allocated
2157  // object, e.g. if the final overrider class is laid out after the virtual
2158  // base that declares a method in the most derived class.
2159  V = CGF.Builder.CreateConstGEP1_32(V, TA.NonVirtual);
2160  }
2161 
2162  // Don't need to bitcast back, the call CodeGen will handle this.
2163  return V;
2164 }
2165 
2166 llvm::Value *
2167 MicrosoftCXXABI::performReturnAdjustment(CodeGenFunction &CGF, Address Ret,
2168  const ReturnAdjustment &RA) {
2169  if (RA.isEmpty())
2170  return Ret.getPointer();
2171 
2172  auto OrigTy = Ret.getType();
2173  Ret = CGF.Builder.CreateElementBitCast(Ret, CGF.Int8Ty);
2174 
2175  llvm::Value *V = Ret.getPointer();
2176  if (RA.Virtual.Microsoft.VBIndex) {
2177  assert(RA.Virtual.Microsoft.VBIndex > 0);
2178  int32_t IntSize = CGF.getIntSize().getQuantity();
2179  llvm::Value *VBPtr;
2180  llvm::Value *VBaseOffset =
2181  GetVBaseOffsetFromVBPtr(CGF, Ret, RA.Virtual.Microsoft.VBPtrOffset,
2182  IntSize * RA.Virtual.Microsoft.VBIndex, &VBPtr);
2183  V = CGF.Builder.CreateInBoundsGEP(VBPtr, VBaseOffset);
2184  }
2185 
2186  if (RA.NonVirtual)
2187  V = CGF.Builder.CreateConstInBoundsGEP1_32(CGF.Int8Ty, V, RA.NonVirtual);
2188 
2189  // Cast back to the original type.
2190  return CGF.Builder.CreateBitCast(V, OrigTy);
2191 }
2192 
2193 bool MicrosoftCXXABI::requiresArrayCookie(const CXXDeleteExpr *expr,
2194  QualType elementType) {
2195  // Microsoft seems to completely ignore the possibility of a
2196  // two-argument usual deallocation function.
2197  return elementType.isDestructedType();
2198 }
2199 
2200 bool MicrosoftCXXABI::requiresArrayCookie(const CXXNewExpr *expr) {
2201  // Microsoft seems to completely ignore the possibility of a
2202  // two-argument usual deallocation function.
2203  return expr->getAllocatedType().isDestructedType();
2204 }
2205 
2206 CharUnits MicrosoftCXXABI::getArrayCookieSizeImpl(QualType type) {
2207  // The array cookie is always a size_t; we then pad that out to the
2208  // alignment of the element type.
2209  ASTContext &Ctx = getContext();
2210  return std::max(Ctx.getTypeSizeInChars(Ctx.getSizeType()),
2211  Ctx.getTypeAlignInChars(type));
2212 }
2213 
2214 llvm::Value *MicrosoftCXXABI::readArrayCookieImpl(CodeGenFunction &CGF,
2215  Address allocPtr,
2216  CharUnits cookieSize) {
2217  Address numElementsPtr =
2218  CGF.Builder.CreateElementBitCast(allocPtr, CGF.SizeTy);
2219  return CGF.Builder.CreateLoad(numElementsPtr);
2220 }
2221 
2222 Address MicrosoftCXXABI::InitializeArrayCookie(CodeGenFunction &CGF,
2223  Address newPtr,
2224  llvm::Value *numElements,
2225  const CXXNewExpr *expr,
2226  QualType elementType) {
2227  assert(requiresArrayCookie(expr));
2228 
2229  // The size of the cookie.
2230  CharUnits cookieSize = getArrayCookieSizeImpl(elementType);
2231 
2232  // Compute an offset to the cookie.
2233  Address cookiePtr = newPtr;
2234 
2235  // Write the number of elements into the appropriate slot.
2236  Address numElementsPtr
2237  = CGF.Builder.CreateElementBitCast(cookiePtr, CGF.SizeTy);
2238  CGF.Builder.CreateStore(numElements, numElementsPtr);
2239 
2240  // Finally, compute a pointer to the actual data buffer by skipping
2241  // over the cookie completely.
2242  return CGF.Builder.CreateConstInBoundsByteGEP(newPtr, cookieSize);
2243 }
2244 
2246  llvm::FunctionCallee Dtor,
2247  llvm::Constant *Addr) {
2248  // Create a function which calls the destructor.
2249  llvm::Constant *DtorStub = CGF.createAtExitStub(VD, Dtor, Addr);
2250 
2251  // extern "C" int __tlregdtor(void (*f)(void));
2252  llvm::FunctionType *TLRegDtorTy = llvm::FunctionType::get(
2253  CGF.IntTy, DtorStub->getType(), /*IsVarArg=*/false);
2254 
2255  llvm::FunctionCallee TLRegDtor = CGF.CGM.CreateRuntimeFunction(
2256  TLRegDtorTy, "__tlregdtor", llvm::AttributeList(), /*Local=*/true);
2257  if (llvm::Function *TLRegDtorFn =
2258  dyn_cast<llvm::Function>(TLRegDtor.getCallee()))
2259  TLRegDtorFn->setDoesNotThrow();
2260 
2261  CGF.EmitNounwindRuntimeCall(TLRegDtor, DtorStub);
2262 }
2263 
2264 void MicrosoftCXXABI::registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
2265  llvm::FunctionCallee Dtor,
2266  llvm::Constant *Addr) {
2267  if (D.isNoDestroy(CGM.getContext()))
2268  return;
2269 
2270  if (D.getTLSKind())
2271  return emitGlobalDtorWithTLRegDtor(CGF, D, Dtor, Addr);
2272 
2273  // The default behavior is to use atexit.
2274  CGF.registerGlobalDtorWithAtExit(D, Dtor, Addr);
2275 }
2276 
2277 void MicrosoftCXXABI::EmitThreadLocalInitFuncs(
2278  CodeGenModule &CGM, ArrayRef<const VarDecl *> CXXThreadLocals,
2279  ArrayRef<llvm::Function *> CXXThreadLocalInits,
2280  ArrayRef<const VarDecl *> CXXThreadLocalInitVars) {
2281  if (CXXThreadLocalInits.empty())
2282  return;
2283 
2284  CGM.AppendLinkerOptions(CGM.getTarget().getTriple().getArch() ==
2285  llvm::Triple::x86
2286  ? "/include:___dyn_tls_init@12"
2287  : "/include:__dyn_tls_init");
2288 
2289  // This will create a GV in the .CRT$XDU section. It will point to our
2290  // initialization function. The CRT will call all of these function
2291  // pointers at start-up time and, eventually, at thread-creation time.
2292  auto AddToXDU = [&CGM](llvm::Function *InitFunc) {
2293  llvm::GlobalVariable *InitFuncPtr = new llvm::GlobalVariable(
2294  CGM.getModule(), InitFunc->getType(), /*IsConstant=*/true,
2296  Twine(InitFunc->getName(), "$initializer$"));
2297  InitFuncPtr->setSection(".CRT$XDU");
2298  // This variable has discardable linkage, we have to add it to @llvm.used to
2299  // ensure it won't get discarded.
2300  CGM.addUsedGlobal(InitFuncPtr);
2301  return InitFuncPtr;
2302  };
2303 
2304  std::vector<llvm::Function *> NonComdatInits;
2305  for (size_t I = 0, E = CXXThreadLocalInitVars.size(); I != E; ++I) {
2306  llvm::GlobalVariable *GV = cast<llvm::GlobalVariable>(
2307  CGM.GetGlobalValue(CGM.getMangledName(CXXThreadLocalInitVars[I])));
2308  llvm::Function *F = CXXThreadLocalInits[I];
2309 
2310  // If the GV is already in a comdat group, then we have to join it.
2311  if (llvm::Comdat *C = GV->getComdat())
2312  AddToXDU(F)->setComdat(C);
2313  else
2314  NonComdatInits.push_back(F);
2315  }
2316 
2317  if (!NonComdatInits.empty()) {
2318  llvm::FunctionType *FTy =
2319  llvm::FunctionType::get(CGM.VoidTy, /*isVarArg=*/false);
2320  llvm::Function *InitFunc = CGM.CreateGlobalInitOrDestructFunction(
2321  FTy, "__tls_init", CGM.getTypes().arrangeNullaryFunction(),
2322  SourceLocation(), /*TLS=*/true);
2323  CodeGenFunction(CGM).GenerateCXXGlobalInitFunc(InitFunc, NonComdatInits);
2324 
2325  AddToXDU(InitFunc);
2326  }
2327 }
2328 
2329 LValue MicrosoftCXXABI::EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF,
2330  const VarDecl *VD,
2331  QualType LValType) {
2332  CGF.CGM.ErrorUnsupported(VD, "thread wrappers");
2333  return LValue();
2334 }
2335 
2337  StringRef VarName("_Init_thread_epoch");
2338  CharUnits Align = CGM.getIntAlign();
2339  if (auto *GV = CGM.getModule().getNamedGlobal(VarName))
2340  return ConstantAddress(GV, Align);
2341  auto *GV = new llvm::GlobalVariable(
2342  CGM.getModule(), CGM.IntTy,
2343  /*Constant=*/false, llvm::GlobalVariable::ExternalLinkage,
2344  /*Initializer=*/nullptr, VarName,
2345  /*InsertBefore=*/nullptr, llvm::GlobalVariable::GeneralDynamicTLSModel);
2346  GV->setAlignment(Align.getQuantity());
2347  return ConstantAddress(GV, Align);
2348 }
2349 
2350 static llvm::FunctionCallee getInitThreadHeaderFn(CodeGenModule &CGM) {
2351  llvm::FunctionType *FTy =
2352  llvm::FunctionType::get(llvm::Type::getVoidTy(CGM.getLLVMContext()),
2353  CGM.IntTy->getPointerTo(), /*isVarArg=*/false);
2354  return CGM.CreateRuntimeFunction(
2355  FTy, "_Init_thread_header",
2356  llvm::AttributeList::get(CGM.getLLVMContext(),
2357  llvm::AttributeList::FunctionIndex,
2358  llvm::Attribute::NoUnwind),
2359  /*Local=*/true);
2360 }
2361 
2362 static llvm::FunctionCallee getInitThreadFooterFn(CodeGenModule &CGM) {
2363  llvm::FunctionType *FTy =
2364  llvm::FunctionType::get(llvm::Type::getVoidTy(CGM.getLLVMContext()),
2365  CGM.IntTy->getPointerTo(), /*isVarArg=*/false);
2366  return CGM.CreateRuntimeFunction(
2367  FTy, "_Init_thread_footer",
2368  llvm::AttributeList::get(CGM.getLLVMContext(),
2369  llvm::AttributeList::FunctionIndex,
2370  llvm::Attribute::NoUnwind),
2371  /*Local=*/true);
2372 }
2373 
2374 static llvm::FunctionCallee getInitThreadAbortFn(CodeGenModule &CGM) {
2375  llvm::FunctionType *FTy =
2376  llvm::FunctionType::get(llvm::Type::getVoidTy(CGM.getLLVMContext()),
2377  CGM.IntTy->getPointerTo(), /*isVarArg=*/false);
2378  return CGM.CreateRuntimeFunction(
2379  FTy, "_Init_thread_abort",
2380  llvm::AttributeList::get(CGM.getLLVMContext(),
2381  llvm::AttributeList::FunctionIndex,
2382  llvm::Attribute::NoUnwind),
2383  /*Local=*/true);
2384 }
2385 
2386 namespace {
2387 struct ResetGuardBit final : EHScopeStack::Cleanup {
2388  Address Guard;
2389  unsigned GuardNum;
2390  ResetGuardBit(Address Guard, unsigned GuardNum)
2391  : Guard(Guard), GuardNum(GuardNum) {}
2392 
2393  void Emit(CodeGenFunction &CGF, Flags flags) override {
2394  // Reset the bit in the mask so that the static variable may be
2395  // reinitialized.
2396  CGBuilderTy &Builder = CGF.Builder;
2397  llvm::LoadInst *LI = Builder.CreateLoad(Guard);
2398  llvm::ConstantInt *Mask =
2399  llvm::ConstantInt::get(CGF.IntTy, ~(1ULL << GuardNum));
2400  Builder.CreateStore(Builder.CreateAnd(LI, Mask), Guard);
2401  }
2402 };
2403 
2404 struct CallInitThreadAbort final : EHScopeStack::Cleanup {
2405  llvm::Value *Guard;
2406  CallInitThreadAbort(Address Guard) : Guard(Guard.getPointer()) {}
2407 
2408  void Emit(CodeGenFunction &CGF, Flags flags) override {
2409  // Calling _Init_thread_abort will reset the guard's state.
2411  }
2412 };
2413 }
2414 
2415 void MicrosoftCXXABI::EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
2416  llvm::GlobalVariable *GV,
2417  bool PerformInit) {
2418  // MSVC only uses guards for static locals.
2419  if (!D.isStaticLocal()) {
2420  assert(GV->hasWeakLinkage() || GV->hasLinkOnceLinkage());
2421  // GlobalOpt is allowed to discard the initializer, so use linkonce_odr.
2422  llvm::Function *F = CGF.CurFn;
2423  F->setLinkage(llvm::GlobalValue::LinkOnceODRLinkage);
2424  F->setComdat(CGM.getModule().getOrInsertComdat(F->getName()));
2425  CGF.EmitCXXGlobalVarDeclInit(D, GV, PerformInit);
2426  return;
2427  }
2428 
2429  bool ThreadlocalStatic = D.getTLSKind();
2430  bool ThreadsafeStatic = getContext().getLangOpts().ThreadsafeStatics;
2431 
2432  // Thread-safe static variables which aren't thread-specific have a
2433  // per-variable guard.
2434  bool HasPerVariableGuard = ThreadsafeStatic && !ThreadlocalStatic;
2435 
2436  CGBuilderTy &Builder = CGF.Builder;
2437  llvm::IntegerType *GuardTy = CGF.Int32Ty;
2438  llvm::ConstantInt *Zero = llvm::ConstantInt::get(GuardTy, 0);
2439  CharUnits GuardAlign = CharUnits::fromQuantity(4);
2440 
2441  // Get the guard variable for this function if we have one already.
2442  GuardInfo *GI = nullptr;
2443  if (ThreadlocalStatic)
2444  GI = &ThreadLocalGuardVariableMap[D.getDeclContext()];
2445  else if (!ThreadsafeStatic)
2446  GI = &GuardVariableMap[D.getDeclContext()];
2447 
2448  llvm::GlobalVariable *GuardVar = GI ? GI->Guard : nullptr;
2449  unsigned GuardNum;
2450  if (D.isExternallyVisible()) {
2451  // Externally visible variables have to be numbered in Sema to properly
2452  // handle unreachable VarDecls.
2453  GuardNum = getContext().getStaticLocalNumber(&D);
2454  assert(GuardNum > 0);
2455  GuardNum--;
2456  } else if (HasPerVariableGuard) {
2457  GuardNum = ThreadSafeGuardNumMap[D.getDeclContext()]++;
2458  } else {
2459  // Non-externally visible variables are numbered here in CodeGen.
2460  GuardNum = GI->BitIndex++;
2461  }
2462 
2463  if (!HasPerVariableGuard && GuardNum >= 32) {
2464  if (D.isExternallyVisible())
2465  ErrorUnsupportedABI(CGF, "more than 32 guarded initializations");
2466  GuardNum %= 32;
2467  GuardVar = nullptr;
2468  }
2469 
2470  if (!GuardVar) {
2471  // Mangle the name for the guard.
2472  SmallString<256> GuardName;
2473  {
2474  llvm::raw_svector_ostream Out(GuardName);
2475  if (HasPerVariableGuard)
2476  getMangleContext().mangleThreadSafeStaticGuardVariable(&D, GuardNum,
2477  Out);
2478  else
2479  getMangleContext().mangleStaticGuardVariable(&D, Out);
2480  }
2481 
2482  // Create the guard variable with a zero-initializer. Just absorb linkage,
2483  // visibility and dll storage class from the guarded variable.
2484  GuardVar =
2485  new llvm::GlobalVariable(CGM.getModule(), GuardTy, /*isConstant=*/false,
2486  GV->getLinkage(), Zero, GuardName.str());
2487  GuardVar->setVisibility(GV->getVisibility());
2488  GuardVar->setDLLStorageClass(GV->getDLLStorageClass());
2489  GuardVar->setAlignment(GuardAlign.getQuantity());
2490  if (GuardVar->isWeakForLinker())
2491  GuardVar->setComdat(
2492  CGM.getModule().getOrInsertComdat(GuardVar->getName()));
2493  if (D.getTLSKind())
2494  GuardVar->setThreadLocal(true);
2495  if (GI && !HasPerVariableGuard)
2496  GI->Guard = GuardVar;
2497  }
2498 
2499  ConstantAddress GuardAddr(GuardVar, GuardAlign);
2500 
2501  assert(GuardVar->getLinkage() == GV->getLinkage() &&
2502  "static local from the same function had different linkage");
2503 
2504  if (!HasPerVariableGuard) {
2505  // Pseudo code for the test:
2506  // if (!(GuardVar & MyGuardBit)) {
2507  // GuardVar |= MyGuardBit;
2508  // ... initialize the object ...;
2509  // }
2510 
2511  // Test our bit from the guard variable.
2512  llvm::ConstantInt *Bit = llvm::ConstantInt::get(GuardTy, 1ULL << GuardNum);
2513  llvm::LoadInst *LI = Builder.CreateLoad(GuardAddr);
2514  llvm::Value *NeedsInit =
2515  Builder.CreateICmpEQ(Builder.CreateAnd(LI, Bit), Zero);
2516  llvm::BasicBlock *InitBlock = CGF.createBasicBlock("init");
2517  llvm::BasicBlock *EndBlock = CGF.createBasicBlock("init.end");
2518  CGF.EmitCXXGuardedInitBranch(NeedsInit, InitBlock, EndBlock,
2520 
2521  // Set our bit in the guard variable and emit the initializer and add a global
2522  // destructor if appropriate.
2523  CGF.EmitBlock(InitBlock);
2524  Builder.CreateStore(Builder.CreateOr(LI, Bit), GuardAddr);
2525  CGF.EHStack.pushCleanup<ResetGuardBit>(EHCleanup, GuardAddr, GuardNum);
2526  CGF.EmitCXXGlobalVarDeclInit(D, GV, PerformInit);
2527  CGF.PopCleanupBlock();
2528  Builder.CreateBr(EndBlock);
2529 
2530  // Continue.
2531  CGF.EmitBlock(EndBlock);
2532  } else {
2533  // Pseudo code for the test:
2534  // if (TSS > _Init_thread_epoch) {
2535  // _Init_thread_header(&TSS);
2536  // if (TSS == -1) {
2537  // ... initialize the object ...;
2538  // _Init_thread_footer(&TSS);
2539  // }
2540  // }
2541  //
2542  // The algorithm is almost identical to what can be found in the appendix
2543  // found in N2325.
2544 
2545  // This BasicBLock determines whether or not we have any work to do.
2546  llvm::LoadInst *FirstGuardLoad = Builder.CreateLoad(GuardAddr);
2547  FirstGuardLoad->setOrdering(llvm::AtomicOrdering::Unordered);
2548  llvm::LoadInst *InitThreadEpoch =
2549  Builder.CreateLoad(getInitThreadEpochPtr(CGM));
2550  llvm::Value *IsUninitialized =
2551  Builder.CreateICmpSGT(FirstGuardLoad, InitThreadEpoch);
2552  llvm::BasicBlock *AttemptInitBlock = CGF.createBasicBlock("init.attempt");
2553  llvm::BasicBlock *EndBlock = CGF.createBasicBlock("init.end");
2554  CGF.EmitCXXGuardedInitBranch(IsUninitialized, AttemptInitBlock, EndBlock,
2556 
2557  // This BasicBlock attempts to determine whether or not this thread is
2558  // responsible for doing the initialization.
2559  CGF.EmitBlock(AttemptInitBlock);
2561  GuardAddr.getPointer());
2562  llvm::LoadInst *SecondGuardLoad = Builder.CreateLoad(GuardAddr);
2563  SecondGuardLoad->setOrdering(llvm::AtomicOrdering::Unordered);
2564  llvm::Value *ShouldDoInit =
2565  Builder.CreateICmpEQ(SecondGuardLoad, getAllOnesInt());
2566  llvm::BasicBlock *InitBlock = CGF.createBasicBlock("init");
2567  Builder.CreateCondBr(ShouldDoInit, InitBlock, EndBlock);
2568 
2569  // Ok, we ended up getting selected as the initializing thread.
2570  CGF.EmitBlock(InitBlock);
2571  CGF.EHStack.pushCleanup<CallInitThreadAbort>(EHCleanup, GuardAddr);
2572  CGF.EmitCXXGlobalVarDeclInit(D, GV, PerformInit);
2573  CGF.PopCleanupBlock();
2575  GuardAddr.getPointer());
2576  Builder.CreateBr(EndBlock);
2577 
2578  CGF.EmitBlock(EndBlock);
2579  }
2580 }
2581 
2582 bool MicrosoftCXXABI::isZeroInitializable(const MemberPointerType *MPT) {
2583  // Null-ness for function memptrs only depends on the first field, which is
2584  // the function pointer. The rest don't matter, so we can zero initialize.
2585  if (MPT->isMemberFunctionPointer())
2586  return true;
2587 
2588  // The virtual base adjustment field is always -1 for null, so if we have one
2589  // we can't zero initialize. The field offset is sometimes also -1 if 0 is a
2590  // valid field offset.
2591  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
2592  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
2593  return (!MSInheritanceAttr::hasVBTableOffsetField(Inheritance) &&
2594  RD->nullFieldOffsetIsZero());
2595 }
2596 
2597 llvm::Type *
2598 MicrosoftCXXABI::ConvertMemberPointerType(const MemberPointerType *MPT) {
2599  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
2600  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
2602  if (MPT->isMemberFunctionPointer())
2603  fields.push_back(CGM.VoidPtrTy); // FunctionPointerOrVirtualThunk
2604  else
2605  fields.push_back(CGM.IntTy); // FieldOffset
2606 
2607  if (MSInheritanceAttr::hasNVOffsetField(MPT->isMemberFunctionPointer(),
2608  Inheritance))
2609  fields.push_back(CGM.IntTy);
2610  if (MSInheritanceAttr::hasVBPtrOffsetField(Inheritance))
2611  fields.push_back(CGM.IntTy);
2612  if (MSInheritanceAttr::hasVBTableOffsetField(Inheritance))
2613  fields.push_back(CGM.IntTy); // VirtualBaseAdjustmentOffset
2614 
2615  if (fields.size() == 1)
2616  return fields[0];
2617  return llvm::StructType::get(CGM.getLLVMContext(), fields);
2618 }
2619 
2620 void MicrosoftCXXABI::
2621 GetNullMemberPointerFields(const MemberPointerType *MPT,
2623  assert(fields.empty());
2624  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
2625  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
2626  if (MPT->isMemberFunctionPointer()) {
2627  // FunctionPointerOrVirtualThunk
2628  fields.push_back(llvm::Constant::getNullValue(CGM.VoidPtrTy));
2629  } else {
2630  if (RD->nullFieldOffsetIsZero())
2631  fields.push_back(getZeroInt()); // FieldOffset
2632  else
2633  fields.push_back(getAllOnesInt()); // FieldOffset
2634  }
2635 
2636  if (MSInheritanceAttr::hasNVOffsetField(MPT->isMemberFunctionPointer(),
2637  Inheritance))
2638  fields.push_back(getZeroInt());
2639  if (MSInheritanceAttr::hasVBPtrOffsetField(Inheritance))
2640  fields.push_back(getZeroInt());
2641  if (MSInheritanceAttr::hasVBTableOffsetField(Inheritance))
2642  fields.push_back(getAllOnesInt());
2643 }
2644 
2645 llvm::Constant *
2646 MicrosoftCXXABI::EmitNullMemberPointer(const MemberPointerType *MPT) {
2648  GetNullMemberPointerFields(MPT, fields);
2649  if (fields.size() == 1)
2650  return fields[0];
2651  llvm::Constant *Res = llvm::ConstantStruct::getAnon(fields);
2652  assert(Res->getType() == ConvertMemberPointerType(MPT));
2653  return Res;
2654 }
2655 
2656 llvm::Constant *
2657 MicrosoftCXXABI::EmitFullMemberPointer(llvm::Constant *FirstField,
2658  bool IsMemberFunction,
2659  const CXXRecordDecl *RD,
2660  CharUnits NonVirtualBaseAdjustment,
2661  unsigned VBTableIndex) {
2662  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
2663 
2664  // Single inheritance class member pointer are represented as scalars instead
2665  // of aggregates.
2666  if (MSInheritanceAttr::hasOnlyOneField(IsMemberFunction, Inheritance))
2667  return FirstField;
2668 
2670  fields.push_back(FirstField);
2671 
2672  if (MSInheritanceAttr::hasNVOffsetField(IsMemberFunction, Inheritance))
2673  fields.push_back(llvm::ConstantInt::get(
2674  CGM.IntTy, NonVirtualBaseAdjustment.getQuantity()));
2675 
2676  if (MSInheritanceAttr::hasVBPtrOffsetField(Inheritance)) {
2677  CharUnits Offs = CharUnits::Zero();
2678  if (VBTableIndex)
2679  Offs = getContext().getASTRecordLayout(RD).getVBPtrOffset();
2680  fields.push_back(llvm::ConstantInt::get(CGM.IntTy, Offs.getQuantity()));
2681  }
2682 
2683  // The rest of the fields are adjusted by conversions to a more derived class.
2684  if (MSInheritanceAttr::hasVBTableOffsetField(Inheritance))
2685  fields.push_back(llvm::ConstantInt::get(CGM.IntTy, VBTableIndex));
2686 
2687  return llvm::ConstantStruct::getAnon(fields);
2688 }
2689 
2690 llvm::Constant *
2691 MicrosoftCXXABI::EmitMemberDataPointer(const MemberPointerType *MPT,
2692  CharUnits offset) {
2693  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
2694  if (RD->getMSInheritanceModel() ==
2695  MSInheritanceAttr::Keyword_virtual_inheritance)
2696  offset -= getContext().getOffsetOfBaseWithVBPtr(RD);
2697  llvm::Constant *FirstField =
2698  llvm::ConstantInt::get(CGM.IntTy, offset.getQuantity());
2699  return EmitFullMemberPointer(FirstField, /*IsMemberFunction=*/false, RD,
2700  CharUnits::Zero(), /*VBTableIndex=*/0);
2701 }
2702 
2703 llvm::Constant *MicrosoftCXXABI::EmitMemberPointer(const APValue &MP,
2704  QualType MPType) {
2705  const MemberPointerType *DstTy = MPType->castAs<MemberPointerType>();
2706  const ValueDecl *MPD = MP.getMemberPointerDecl();
2707  if (!MPD)
2708  return EmitNullMemberPointer(DstTy);
2709 
2710  ASTContext &Ctx = getContext();
2711  ArrayRef<const CXXRecordDecl *> MemberPointerPath = MP.getMemberPointerPath();
2712 
2713  llvm::Constant *C;
2714  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(MPD)) {
2715  C = EmitMemberFunctionPointer(MD);
2716  } else {
2717  CharUnits FieldOffset = Ctx.toCharUnitsFromBits(Ctx.getFieldOffset(MPD));
2718  C = EmitMemberDataPointer(DstTy, FieldOffset);
2719  }
2720 
2721  if (!MemberPointerPath.empty()) {
2722  const CXXRecordDecl *SrcRD = cast<CXXRecordDecl>(MPD->getDeclContext());
2723  const Type *SrcRecTy = Ctx.getTypeDeclType(SrcRD).getTypePtr();
2724  const MemberPointerType *SrcTy =
2725  Ctx.getMemberPointerType(DstTy->getPointeeType(), SrcRecTy)
2726  ->castAs<MemberPointerType>();
2727 
2728  bool DerivedMember = MP.isMemberPointerToDerivedMember();
2729  SmallVector<const CXXBaseSpecifier *, 4> DerivedToBasePath;
2730  const CXXRecordDecl *PrevRD = SrcRD;
2731  for (const CXXRecordDecl *PathElem : MemberPointerPath) {
2732  const CXXRecordDecl *Base = nullptr;
2733  const CXXRecordDecl *Derived = nullptr;
2734  if (DerivedMember) {
2735  Base = PathElem;
2736  Derived = PrevRD;
2737  } else {
2738  Base = PrevRD;
2739  Derived = PathElem;
2740  }
2741  for (const CXXBaseSpecifier &BS : Derived->bases())
2742  if (BS.getType()->getAsCXXRecordDecl()->getCanonicalDecl() ==
2743  Base->getCanonicalDecl())
2744  DerivedToBasePath.push_back(&BS);
2745  PrevRD = PathElem;
2746  }
2747  assert(DerivedToBasePath.size() == MemberPointerPath.size());
2748 
2749  CastKind CK = DerivedMember ? CK_DerivedToBaseMemberPointer
2750  : CK_BaseToDerivedMemberPointer;
2751  C = EmitMemberPointerConversion(SrcTy, DstTy, CK, DerivedToBasePath.begin(),
2752  DerivedToBasePath.end(), C);
2753  }
2754  return C;
2755 }
2756 
2757 llvm::Constant *
2758 MicrosoftCXXABI::EmitMemberFunctionPointer(const CXXMethodDecl *MD) {
2759  assert(MD->isInstance() && "Member function must not be static!");
2760 
2761  CharUnits NonVirtualBaseAdjustment = CharUnits::Zero();
2763  CodeGenTypes &Types = CGM.getTypes();
2764 
2765  unsigned VBTableIndex = 0;
2766  llvm::Constant *FirstField;
2767  const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
2768  if (!MD->isVirtual()) {
2769  llvm::Type *Ty;
2770  // Check whether the function has a computable LLVM signature.
2771  if (Types.isFuncTypeConvertible(FPT)) {
2772  // The function has a computable LLVM signature; use the correct type.
2773  Ty = Types.GetFunctionType(Types.arrangeCXXMethodDeclaration(MD));
2774  } else {
2775  // Use an arbitrary non-function type to tell GetAddrOfFunction that the
2776  // function type is incomplete.
2777  Ty = CGM.PtrDiffTy;
2778  }
2779  FirstField = CGM.GetAddrOfFunction(MD, Ty);
2780  } else {
2781  auto &VTableContext = CGM.getMicrosoftVTableContext();
2782  MethodVFTableLocation ML = VTableContext.getMethodVFTableLocation(MD);
2783  FirstField = EmitVirtualMemPtrThunk(MD, ML);
2784  // Include the vfptr adjustment if the method is in a non-primary vftable.
2785  NonVirtualBaseAdjustment += ML.VFPtrOffset;
2786  if (ML.VBase)
2787  VBTableIndex = VTableContext.getVBTableIndex(RD, ML.VBase) * 4;
2788  }
2789 
2790  if (VBTableIndex == 0 &&
2791  RD->getMSInheritanceModel() ==
2792  MSInheritanceAttr::Keyword_virtual_inheritance)
2793  NonVirtualBaseAdjustment -= getContext().getOffsetOfBaseWithVBPtr(RD);
2794 
2795  // The rest of the fields are common with data member pointers.
2796  FirstField = llvm::ConstantExpr::getBitCast(FirstField, CGM.VoidPtrTy);
2797  return EmitFullMemberPointer(FirstField, /*IsMemberFunction=*/true, RD,
2798  NonVirtualBaseAdjustment, VBTableIndex);
2799 }
2800 
2801 /// Member pointers are the same if they're either bitwise identical *or* both
2802 /// null. Null-ness for function members is determined by the first field,
2803 /// while for data member pointers we must compare all fields.
2804 llvm::Value *
2805 MicrosoftCXXABI::EmitMemberPointerComparison(CodeGenFunction &CGF,
2806  llvm::Value *L,
2807  llvm::Value *R,
2808  const MemberPointerType *MPT,
2809  bool Inequality) {
2810  CGBuilderTy &Builder = CGF.Builder;
2811 
2812  // Handle != comparisons by switching the sense of all boolean operations.
2813  llvm::ICmpInst::Predicate Eq;
2814  llvm::Instruction::BinaryOps And, Or;
2815  if (Inequality) {
2816  Eq = llvm::ICmpInst::ICMP_NE;
2817  And = llvm::Instruction::Or;
2819  } else {
2820  Eq = llvm::ICmpInst::ICMP_EQ;
2821  And = llvm::Instruction::And;
2822  Or = llvm::Instruction::Or;
2823  }
2824 
2825  // If this is a single field member pointer (single inheritance), this is a
2826  // single icmp.
2827  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
2828  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
2829  if (MSInheritanceAttr::hasOnlyOneField(MPT->isMemberFunctionPointer(),
2830  Inheritance))
2831  return Builder.CreateICmp(Eq, L, R);
2832 
2833  // Compare the first field.
2834  llvm::Value *L0 = Builder.CreateExtractValue(L, 0, "lhs.0");
2835  llvm::Value *R0 = Builder.CreateExtractValue(R, 0, "rhs.0");
2836  llvm::Value *Cmp0 = Builder.CreateICmp(Eq, L0, R0, "memptr.cmp.first");
2837 
2838  // Compare everything other than the first field.
2839  llvm::Value *Res = nullptr;
2840  llvm::StructType *LType = cast<llvm::StructType>(L->getType());
2841  for (unsigned I = 1, E = LType->getNumElements(); I != E; ++I) {
2842  llvm::Value *LF = Builder.CreateExtractValue(L, I);
2843  llvm::Value *RF = Builder.CreateExtractValue(R, I);
2844  llvm::Value *Cmp = Builder.CreateICmp(Eq, LF, RF, "memptr.cmp.rest");
2845  if (Res)
2846  Res = Builder.CreateBinOp(And, Res, Cmp);
2847  else
2848  Res = Cmp;
2849  }
2850 
2851  // Check if the first field is 0 if this is a function pointer.
2852  if (MPT->isMemberFunctionPointer()) {
2853  // (l1 == r1 && ...) || l0 == 0
2854  llvm::Value *Zero = llvm::Constant::getNullValue(L0->getType());
2855  llvm::Value *IsZero = Builder.CreateICmp(Eq, L0, Zero, "memptr.cmp.iszero");
2856  Res = Builder.CreateBinOp(Or, Res, IsZero);
2857  }
2858 
2859  // Combine the comparison of the first field, which must always be true for
2860  // this comparison to succeeed.
2861  return Builder.CreateBinOp(And, Res, Cmp0, "memptr.cmp");
2862 }
2863 
2864 llvm::Value *
2865 MicrosoftCXXABI::EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
2866  llvm::Value *MemPtr,
2867  const MemberPointerType *MPT) {
2868  CGBuilderTy &Builder = CGF.Builder;
2870  // We only need one field for member functions.
2871  if (MPT->isMemberFunctionPointer())
2872  fields.push_back(llvm::Constant::getNullValue(CGM.VoidPtrTy));
2873  else
2874  GetNullMemberPointerFields(MPT, fields);
2875  assert(!fields.empty());
2876  llvm::Value *FirstField = MemPtr;
2877  if (MemPtr->getType()->isStructTy())
2878  FirstField = Builder.CreateExtractValue(MemPtr, 0);
2879  llvm::Value *Res = Builder.CreateICmpNE(FirstField, fields[0], "memptr.cmp0");
2880 
2881  // For function member pointers, we only need to test the function pointer
2882  // field. The other fields if any can be garbage.
2883  if (MPT->isMemberFunctionPointer())
2884  return Res;
2885 
2886  // Otherwise, emit a series of compares and combine the results.
2887  for (int I = 1, E = fields.size(); I < E; ++I) {
2888  llvm::Value *Field = Builder.CreateExtractValue(MemPtr, I);
2889  llvm::Value *Next = Builder.CreateICmpNE(Field, fields[I], "memptr.cmp");
2890  Res = Builder.CreateOr(Res, Next, "memptr.tobool");
2891  }
2892  return Res;
2893 }
2894 
2895 bool MicrosoftCXXABI::MemberPointerConstantIsNull(const MemberPointerType *MPT,
2896  llvm::Constant *Val) {
2897  // Function pointers are null if the pointer in the first field is null.
2898  if (MPT->isMemberFunctionPointer()) {
2899  llvm::Constant *FirstField = Val->getType()->isStructTy() ?
2900  Val->getAggregateElement(0U) : Val;
2901  return FirstField->isNullValue();
2902  }
2903 
2904  // If it's not a function pointer and it's zero initializable, we can easily
2905  // check zero.
2906  if (isZeroInitializable(MPT) && Val->isNullValue())
2907  return true;
2908 
2909  // Otherwise, break down all the fields for comparison. Hopefully these
2910  // little Constants are reused, while a big null struct might not be.
2912  GetNullMemberPointerFields(MPT, Fields);
2913  if (Fields.size() == 1) {
2914  assert(Val->getType()->isIntegerTy());
2915  return Val == Fields[0];
2916  }
2917 
2918  unsigned I, E;
2919  for (I = 0, E = Fields.size(); I != E; ++I) {
2920  if (Val->getAggregateElement(I) != Fields[I])
2921  break;
2922  }
2923  return I == E;
2924 }
2925 
2926 llvm::Value *
2927 MicrosoftCXXABI::GetVBaseOffsetFromVBPtr(CodeGenFunction &CGF,
2928  Address This,
2929  llvm::Value *VBPtrOffset,
2930  llvm::Value *VBTableOffset,
2931  llvm::Value **VBPtrOut) {
2932  CGBuilderTy &Builder = CGF.Builder;
2933  // Load the vbtable pointer from the vbptr in the instance.
2934  This = Builder.CreateElementBitCast(This, CGM.Int8Ty);
2935  llvm::Value *VBPtr =
2936  Builder.CreateInBoundsGEP(This.getPointer(), VBPtrOffset, "vbptr");
2937  if (VBPtrOut) *VBPtrOut = VBPtr;
2938  VBPtr = Builder.CreateBitCast(VBPtr,
2939  CGM.Int32Ty->getPointerTo(0)->getPointerTo(This.getAddressSpace()));
2940 
2941  CharUnits VBPtrAlign;
2942  if (auto CI = dyn_cast<llvm::ConstantInt>(VBPtrOffset)) {
2943  VBPtrAlign = This.getAlignment().alignmentAtOffset(
2944  CharUnits::fromQuantity(CI->getSExtValue()));
2945  } else {
2946  VBPtrAlign = CGF.getPointerAlign();
2947  }
2948 
2949  llvm::Value *VBTable = Builder.CreateAlignedLoad(VBPtr, VBPtrAlign, "vbtable");
2950 
2951  // Translate from byte offset to table index. It improves analyzability.
2952  llvm::Value *VBTableIndex = Builder.CreateAShr(
2953  VBTableOffset, llvm::ConstantInt::get(VBTableOffset->getType(), 2),
2954  "vbtindex", /*isExact=*/true);
2955 
2956  // Load an i32 offset from the vb-table.
2957  llvm::Value *VBaseOffs = Builder.CreateInBoundsGEP(VBTable, VBTableIndex);
2958  VBaseOffs = Builder.CreateBitCast(VBaseOffs, CGM.Int32Ty->getPointerTo(0));
2959  return Builder.CreateAlignedLoad(VBaseOffs, CharUnits::fromQuantity(4),
2960  "vbase_offs");
2961 }
2962 
2963 // Returns an adjusted base cast to i8*, since we do more address arithmetic on
2964 // it.
2965 llvm::Value *MicrosoftCXXABI::AdjustVirtualBase(
2966  CodeGenFunction &CGF, const Expr *E, const CXXRecordDecl *RD,
2967  Address Base, llvm::Value *VBTableOffset, llvm::Value *VBPtrOffset) {
2968  CGBuilderTy &Builder = CGF.Builder;
2969  Base = Builder.CreateElementBitCast(Base, CGM.Int8Ty);
2970  llvm::BasicBlock *OriginalBB = nullptr;
2971  llvm::BasicBlock *SkipAdjustBB = nullptr;
2972  llvm::BasicBlock *VBaseAdjustBB = nullptr;
2973 
2974  // In the unspecified inheritance model, there might not be a vbtable at all,
2975  // in which case we need to skip the virtual base lookup. If there is a
2976  // vbtable, the first entry is a no-op entry that gives back the original
2977  // base, so look for a virtual base adjustment offset of zero.
2978  if (VBPtrOffset) {
2979  OriginalBB = Builder.GetInsertBlock();
2980  VBaseAdjustBB = CGF.createBasicBlock("memptr.vadjust");
2981  SkipAdjustBB = CGF.createBasicBlock("memptr.skip_vadjust");
2982  llvm::Value *IsVirtual =
2983  Builder.CreateICmpNE(VBTableOffset, getZeroInt(),
2984  "memptr.is_vbase");
2985  Builder.CreateCondBr(IsVirtual, VBaseAdjustBB, SkipAdjustBB);
2986  CGF.EmitBlock(VBaseAdjustBB);
2987  }
2988 
2989  // If we weren't given a dynamic vbptr offset, RD should be complete and we'll
2990  // know the vbptr offset.
2991  if (!VBPtrOffset) {
2992  CharUnits offs = CharUnits::Zero();
2993  if (!RD->hasDefinition()) {
2994  DiagnosticsEngine &Diags = CGF.CGM.getDiags();
2995  unsigned DiagID = Diags.getCustomDiagID(
2997  "member pointer representation requires a "
2998  "complete class type for %0 to perform this expression");
2999  Diags.Report(E->getExprLoc(), DiagID) << RD << E->getSourceRange();
3000  } else if (RD->getNumVBases())
3001  offs = getContext().getASTRecordLayout(RD).getVBPtrOffset();
3002  VBPtrOffset = llvm::ConstantInt::get(CGM.IntTy, offs.getQuantity());
3003  }
3004  llvm::Value *VBPtr = nullptr;
3005  llvm::Value *VBaseOffs =
3006  GetVBaseOffsetFromVBPtr(CGF, Base, VBPtrOffset, VBTableOffset, &VBPtr);
3007  llvm::Value *AdjustedBase = Builder.CreateInBoundsGEP(VBPtr, VBaseOffs);
3008 
3009  // Merge control flow with the case where we didn't have to adjust.
3010  if (VBaseAdjustBB) {
3011  Builder.CreateBr(SkipAdjustBB);
3012  CGF.EmitBlock(SkipAdjustBB);
3013  llvm::PHINode *Phi = Builder.CreatePHI(CGM.Int8PtrTy, 2, "memptr.base");
3014  Phi->addIncoming(Base.getPointer(), OriginalBB);
3015  Phi->addIncoming(AdjustedBase, VBaseAdjustBB);
3016  return Phi;
3017  }
3018  return AdjustedBase;
3019 }
3020 
3021 llvm::Value *MicrosoftCXXABI::EmitMemberDataPointerAddress(
3022  CodeGenFunction &CGF, const Expr *E, Address Base, llvm::Value *MemPtr,
3023  const MemberPointerType *MPT) {
3024  assert(MPT->isMemberDataPointer());
3025  unsigned AS = Base.getAddressSpace();
3026  llvm::Type *PType =
3027  CGF.ConvertTypeForMem(MPT->getPointeeType())->getPointerTo(AS);
3028  CGBuilderTy &Builder = CGF.Builder;
3029  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
3030  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
3031 
3032  // Extract the fields we need, regardless of model. We'll apply them if we
3033  // have them.
3034  llvm::Value *FieldOffset = MemPtr;
3035  llvm::Value *VirtualBaseAdjustmentOffset = nullptr;
3036  llvm::Value *VBPtrOffset = nullptr;
3037  if (MemPtr->getType()->isStructTy()) {
3038  // We need to extract values.
3039  unsigned I = 0;
3040  FieldOffset = Builder.CreateExtractValue(MemPtr, I++);
3041  if (MSInheritanceAttr::hasVBPtrOffsetField(Inheritance))
3042  VBPtrOffset = Builder.CreateExtractValue(MemPtr, I++);
3043  if (MSInheritanceAttr::hasVBTableOffsetField(Inheritance))
3044  VirtualBaseAdjustmentOffset = Builder.CreateExtractValue(MemPtr, I++);
3045  }
3046 
3047  llvm::Value *Addr;
3048  if (VirtualBaseAdjustmentOffset) {
3049  Addr = AdjustVirtualBase(CGF, E, RD, Base, VirtualBaseAdjustmentOffset,
3050  VBPtrOffset);
3051  } else {
3052  Addr = Base.getPointer();
3053  }
3054 
3055  // Cast to char*.
3056  Addr = Builder.CreateBitCast(Addr, CGF.Int8Ty->getPointerTo(AS));
3057 
3058  // Apply the offset, which we assume is non-null.
3059  Addr = Builder.CreateInBoundsGEP(Addr, FieldOffset, "memptr.offset");
3060 
3061  // Cast the address to the appropriate pointer type, adopting the address
3062  // space of the base pointer.
3063  return Builder.CreateBitCast(Addr, PType);
3064 }
3065 
3066 llvm::Value *
3067 MicrosoftCXXABI::EmitMemberPointerConversion(CodeGenFunction &CGF,
3068  const CastExpr *E,
3069  llvm::Value *Src) {
3070  assert(E->getCastKind() == CK_DerivedToBaseMemberPointer ||
3071  E->getCastKind() == CK_BaseToDerivedMemberPointer ||
3072  E->getCastKind() == CK_ReinterpretMemberPointer);
3073 
3074  // Use constant emission if we can.
3075  if (isa<llvm::Constant>(Src))
3076  return EmitMemberPointerConversion(E, cast<llvm::Constant>(Src));
3077 
3078  // We may be adding or dropping fields from the member pointer, so we need
3079  // both types and the inheritance models of both records.
3080  const MemberPointerType *SrcTy =
3082  const MemberPointerType *DstTy = E->getType()->castAs<MemberPointerType>();
3083  bool IsFunc = SrcTy->isMemberFunctionPointer();
3084 
3085  // If the classes use the same null representation, reinterpret_cast is a nop.
3086  bool IsReinterpret = E->getCastKind() == CK_ReinterpretMemberPointer;
3087  if (IsReinterpret && IsFunc)
3088  return Src;
3089 
3090  CXXRecordDecl *SrcRD = SrcTy->getMostRecentCXXRecordDecl();
3091  CXXRecordDecl *DstRD = DstTy->getMostRecentCXXRecordDecl();
3092  if (IsReinterpret &&
3093  SrcRD->nullFieldOffsetIsZero() == DstRD->nullFieldOffsetIsZero())
3094  return Src;
3095 
3096  CGBuilderTy &Builder = CGF.Builder;
3097 
3098  // Branch past the conversion if Src is null.
3099  llvm::Value *IsNotNull = EmitMemberPointerIsNotNull(CGF, Src, SrcTy);
3100  llvm::Constant *DstNull = EmitNullMemberPointer(DstTy);
3101 
3102  // C++ 5.2.10p9: The null member pointer value is converted to the null member
3103  // pointer value of the destination type.
3104  if (IsReinterpret) {
3105  // For reinterpret casts, sema ensures that src and dst are both functions
3106  // or data and have the same size, which means the LLVM types should match.
3107  assert(Src->getType() == DstNull->getType());
3108  return Builder.CreateSelect(IsNotNull, Src, DstNull);
3109  }
3110 
3111  llvm::BasicBlock *OriginalBB = Builder.GetInsertBlock();
3112  llvm::BasicBlock *ConvertBB = CGF.createBasicBlock("memptr.convert");
3113  llvm::BasicBlock *ContinueBB = CGF.createBasicBlock("memptr.converted");
3114  Builder.CreateCondBr(IsNotNull, ConvertBB, ContinueBB);
3115  CGF.EmitBlock(ConvertBB);
3116 
3117  llvm::Value *Dst = EmitNonNullMemberPointerConversion(
3118  SrcTy, DstTy, E->getCastKind(), E->path_begin(), E->path_end(), Src,
3119  Builder);
3120 
3121  Builder.CreateBr(ContinueBB);
3122 
3123  // In the continuation, choose between DstNull and Dst.
3124  CGF.EmitBlock(ContinueBB);
3125  llvm::PHINode *Phi = Builder.CreatePHI(DstNull->getType(), 2, "memptr.converted");
3126  Phi->addIncoming(DstNull, OriginalBB);
3127  Phi->addIncoming(Dst, ConvertBB);
3128  return Phi;
3129 }
3130 
3131 llvm::Value *MicrosoftCXXABI::EmitNonNullMemberPointerConversion(
3132  const MemberPointerType *SrcTy, const MemberPointerType *DstTy, CastKind CK,
3135  CGBuilderTy &Builder) {
3136  const CXXRecordDecl *SrcRD = SrcTy->getMostRecentCXXRecordDecl();
3137  const CXXRecordDecl *DstRD = DstTy->getMostRecentCXXRecordDecl();
3138  MSInheritanceAttr::Spelling SrcInheritance = SrcRD->getMSInheritanceModel();
3139  MSInheritanceAttr::Spelling DstInheritance = DstRD->getMSInheritanceModel();
3140  bool IsFunc = SrcTy->isMemberFunctionPointer();
3141  bool IsConstant = isa<llvm::Constant>(Src);
3142 
3143  // Decompose src.
3144  llvm::Value *FirstField = Src;
3145  llvm::Value *NonVirtualBaseAdjustment = getZeroInt();
3146  llvm::Value *VirtualBaseAdjustmentOffset = getZeroInt();
3147  llvm::Value *VBPtrOffset = getZeroInt();
3148  if (!MSInheritanceAttr::hasOnlyOneField(IsFunc, SrcInheritance)) {
3149  // We need to extract values.
3150  unsigned I = 0;
3151  FirstField = Builder.CreateExtractValue(Src, I++);
3152  if (MSInheritanceAttr::hasNVOffsetField(IsFunc, SrcInheritance))
3153  NonVirtualBaseAdjustment = Builder.CreateExtractValue(Src, I++);
3154  if (MSInheritanceAttr::hasVBPtrOffsetField(SrcInheritance))
3155  VBPtrOffset = Builder.CreateExtractValue(Src, I++);
3156  if (MSInheritanceAttr::hasVBTableOffsetField(SrcInheritance))
3157  VirtualBaseAdjustmentOffset = Builder.CreateExtractValue(Src, I++);
3158  }
3159 
3160  bool IsDerivedToBase = (CK == CK_DerivedToBaseMemberPointer);
3161  const MemberPointerType *DerivedTy = IsDerivedToBase ? SrcTy : DstTy;
3162  const CXXRecordDecl *DerivedClass = DerivedTy->getMostRecentCXXRecordDecl();
3163 
3164  // For data pointers, we adjust the field offset directly. For functions, we
3165  // have a separate field.
3166  llvm::Value *&NVAdjustField = IsFunc ? NonVirtualBaseAdjustment : FirstField;
3167 
3168  // The virtual inheritance model has a quirk: the virtual base table is always
3169  // referenced when dereferencing a member pointer even if the member pointer
3170  // is non-virtual. This is accounted for by adjusting the non-virtual offset
3171  // to point backwards to the top of the MDC from the first VBase. Undo this
3172  // adjustment to normalize the member pointer.
3173  llvm::Value *SrcVBIndexEqZero =
3174  Builder.CreateICmpEQ(VirtualBaseAdjustmentOffset, getZeroInt());
3175  if (SrcInheritance == MSInheritanceAttr::Keyword_virtual_inheritance) {
3176  if (int64_t SrcOffsetToFirstVBase =
3177  getContext().getOffsetOfBaseWithVBPtr(SrcRD).getQuantity()) {
3178  llvm::Value *UndoSrcAdjustment = Builder.CreateSelect(
3179  SrcVBIndexEqZero,
3180  llvm::ConstantInt::get(CGM.IntTy, SrcOffsetToFirstVBase),
3181  getZeroInt());
3182  NVAdjustField = Builder.CreateNSWAdd(NVAdjustField, UndoSrcAdjustment);
3183  }
3184  }
3185 
3186  // A non-zero vbindex implies that we are dealing with a source member in a
3187  // floating virtual base in addition to some non-virtual offset. If the
3188  // vbindex is zero, we are dealing with a source that exists in a non-virtual,
3189  // fixed, base. The difference between these two cases is that the vbindex +
3190  // nvoffset *always* point to the member regardless of what context they are
3191  // evaluated in so long as the vbindex is adjusted. A member inside a fixed
3192  // base requires explicit nv adjustment.
3193  llvm::Constant *BaseClassOffset = llvm::ConstantInt::get(
3194  CGM.IntTy,
3195  CGM.computeNonVirtualBaseClassOffset(DerivedClass, PathBegin, PathEnd)
3196  .getQuantity());
3197 
3198  llvm::Value *NVDisp;
3199  if (IsDerivedToBase)
3200  NVDisp = Builder.CreateNSWSub(NVAdjustField, BaseClassOffset, "adj");
3201  else
3202  NVDisp = Builder.CreateNSWAdd(NVAdjustField, BaseClassOffset, "adj");
3203 
3204  NVAdjustField = Builder.CreateSelect(SrcVBIndexEqZero, NVDisp, getZeroInt());
3205 
3206  // Update the vbindex to an appropriate value in the destination because
3207  // SrcRD's vbtable might not be a strict prefix of the one in DstRD.
3208  llvm::Value *DstVBIndexEqZero = SrcVBIndexEqZero;
3209  if (MSInheritanceAttr::hasVBTableOffsetField(DstInheritance) &&
3210  MSInheritanceAttr::hasVBTableOffsetField(SrcInheritance)) {
3211  if (llvm::GlobalVariable *VDispMap =
3212  getAddrOfVirtualDisplacementMap(SrcRD, DstRD)) {
3213  llvm::Value *VBIndex = Builder.CreateExactUDiv(
3214  VirtualBaseAdjustmentOffset, llvm::ConstantInt::get(CGM.IntTy, 4));
3215  if (IsConstant) {
3216  llvm::Constant *Mapping = VDispMap->getInitializer();
3217  VirtualBaseAdjustmentOffset =
3218  Mapping->getAggregateElement(cast<llvm::Constant>(VBIndex));
3219  } else {
3220  llvm::Value *Idxs[] = {getZeroInt(), VBIndex};
3221  VirtualBaseAdjustmentOffset =
3222  Builder.CreateAlignedLoad(Builder.CreateInBoundsGEP(VDispMap, Idxs),
3224  }
3225 
3226  DstVBIndexEqZero =
3227  Builder.CreateICmpEQ(VirtualBaseAdjustmentOffset, getZeroInt());
3228  }
3229  }
3230 
3231  // Set the VBPtrOffset to zero if the vbindex is zero. Otherwise, initialize
3232  // it to the offset of the vbptr.
3233  if (MSInheritanceAttr::hasVBPtrOffsetField(DstInheritance)) {
3234  llvm::Value *DstVBPtrOffset = llvm::ConstantInt::get(
3235  CGM.IntTy,
3236  getContext().getASTRecordLayout(DstRD).getVBPtrOffset().getQuantity());
3237  VBPtrOffset =
3238  Builder.CreateSelect(DstVBIndexEqZero, getZeroInt(), DstVBPtrOffset);
3239  }
3240 
3241  // Likewise, apply a similar adjustment so that dereferencing the member
3242  // pointer correctly accounts for the distance between the start of the first
3243  // virtual base and the top of the MDC.
3244  if (DstInheritance == MSInheritanceAttr::Keyword_virtual_inheritance) {
3245  if (int64_t DstOffsetToFirstVBase =
3246  getContext().getOffsetOfBaseWithVBPtr(DstRD).getQuantity()) {
3247  llvm::Value *DoDstAdjustment = Builder.CreateSelect(
3248  DstVBIndexEqZero,
3249  llvm::ConstantInt::get(CGM.IntTy, DstOffsetToFirstVBase),
3250  getZeroInt());
3251  NVAdjustField = Builder.CreateNSWSub(NVAdjustField, DoDstAdjustment);
3252  }
3253  }
3254 
3255  // Recompose dst from the null struct and the adjusted fields from src.
3256  llvm::Value *Dst;
3257  if (MSInheritanceAttr::hasOnlyOneField(IsFunc, DstInheritance)) {
3258  Dst = FirstField;
3259  } else {
3260  Dst = llvm::UndefValue::get(ConvertMemberPointerType(DstTy));
3261  unsigned Idx = 0;
3262  Dst = Builder.CreateInsertValue(Dst, FirstField, Idx++);
3263  if (MSInheritanceAttr::hasNVOffsetField(IsFunc, DstInheritance))
3264  Dst = Builder.CreateInsertValue(Dst, NonVirtualBaseAdjustment, Idx++);
3265  if (MSInheritanceAttr::hasVBPtrOffsetField(DstInheritance))
3266  Dst = Builder.CreateInsertValue(Dst, VBPtrOffset, Idx++);
3267  if (MSInheritanceAttr::hasVBTableOffsetField(DstInheritance))
3268  Dst = Builder.CreateInsertValue(Dst, VirtualBaseAdjustmentOffset, Idx++);
3269  }
3270  return Dst;
3271 }
3272 
3273 llvm::Constant *
3274 MicrosoftCXXABI::EmitMemberPointerConversion(const CastExpr *E,
3275  llvm::Constant *Src) {
3276  const MemberPointerType *SrcTy =
3278  const MemberPointerType *DstTy = E->getType()->castAs<MemberPointerType>();
3279 
3280  CastKind CK = E->getCastKind();
3281 
3282  return EmitMemberPointerConversion(SrcTy, DstTy, CK, E->path_begin(),
3283  E->path_end(), Src);
3284 }
3285 
3286 llvm::Constant *MicrosoftCXXABI::EmitMemberPointerConversion(
3287  const MemberPointerType *SrcTy, const MemberPointerType *DstTy, CastKind CK,
3289  CastExpr::path_const_iterator PathEnd, llvm::Constant *Src) {
3290  assert(CK == CK_DerivedToBaseMemberPointer ||
3291  CK == CK_BaseToDerivedMemberPointer ||
3292  CK == CK_ReinterpretMemberPointer);
3293  // If src is null, emit a new null for dst. We can't return src because dst
3294  // might have a new representation.
3295  if (MemberPointerConstantIsNull(SrcTy, Src))
3296  return EmitNullMemberPointer(DstTy);
3297 
3298  // We don't need to do anything for reinterpret_casts of non-null member
3299  // pointers. We should only get here when the two type representations have
3300  // the same size.
3301  if (CK == CK_ReinterpretMemberPointer)
3302  return Src;
3303 
3304  CGBuilderTy Builder(CGM, CGM.getLLVMContext());
3305  auto *Dst = cast<llvm::Constant>(EmitNonNullMemberPointerConversion(
3306  SrcTy, DstTy, CK, PathBegin, PathEnd, Src, Builder));
3307 
3308  return Dst;
3309 }
3310 
3311 CGCallee MicrosoftCXXABI::EmitLoadOfMemberFunctionPointer(
3312  CodeGenFunction &CGF, const Expr *E, Address This,
3313  llvm::Value *&ThisPtrForCall, llvm::Value *MemPtr,
3314  const MemberPointerType *MPT) {
3315  assert(MPT->isMemberFunctionPointer());
3316  const FunctionProtoType *FPT =
3318  const CXXRecordDecl *RD = MPT->getMostRecentCXXRecordDecl();
3319  llvm::FunctionType *FTy = CGM.getTypes().GetFunctionType(
3320  CGM.getTypes().arrangeCXXMethodType(RD, FPT, /*FD=*/nullptr));
3321  CGBuilderTy &Builder = CGF.Builder;
3322 
3323  MSInheritanceAttr::Spelling Inheritance = RD->getMSInheritanceModel();
3324 
3325  // Extract the fields we need, regardless of model. We'll apply them if we
3326  // have them.
3327  llvm::Value *FunctionPointer = MemPtr;
3328  llvm::Value *NonVirtualBaseAdjustment = nullptr;
3329  llvm::Value *VirtualBaseAdjustmentOffset = nullptr;
3330  llvm::Value *VBPtrOffset = nullptr;
3331  if (MemPtr->getType()->isStructTy()) {
3332  // We need to extract values.
3333  unsigned I = 0;
3334  FunctionPointer = Builder.CreateExtractValue(MemPtr, I++);
3335  if (MSInheritanceAttr::hasNVOffsetField(MPT, Inheritance))
3336  NonVirtualBaseAdjustment = Builder.CreateExtractValue(MemPtr, I++);
3337  if (MSInheritanceAttr::hasVBPtrOffsetField(Inheritance))
3338  VBPtrOffset = Builder.CreateExtractValue(MemPtr, I++);
3339  if (MSInheritanceAttr::hasVBTableOffsetField(Inheritance))
3340  VirtualBaseAdjustmentOffset = Builder.CreateExtractValue(MemPtr, I++);
3341  }
3342 
3343  if (VirtualBaseAdjustmentOffset) {
3344  ThisPtrForCall = AdjustVirtualBase(CGF, E, RD, This,
3345  VirtualBaseAdjustmentOffset, VBPtrOffset);
3346  } else {
3347  ThisPtrForCall = This.getPointer();
3348  }
3349 
3350  if (NonVirtualBaseAdjustment) {
3351  // Apply the adjustment and cast back to the original struct type.
3352  llvm::Value *Ptr = Builder.CreateBitCast(ThisPtrForCall, CGF.Int8PtrTy);
3353  Ptr = Builder.CreateInBoundsGEP(Ptr, NonVirtualBaseAdjustment);
3354  ThisPtrForCall = Builder.CreateBitCast(Ptr, ThisPtrForCall->getType(),
3355  "this.adjusted");
3356  }
3357 
3358  FunctionPointer =
3359  Builder.CreateBitCast(FunctionPointer, FTy->getPointerTo());
3360  CGCallee Callee(FPT, FunctionPointer);
3361  return Callee;
3362 }
3363 
3365  return new MicrosoftCXXABI(CGM);
3366 }
3367 
3368 // MS RTTI Overview:
3369 // The run time type information emitted by cl.exe contains 5 distinct types of
3370 // structures. Many of them reference each other.
3371 //
3372 // TypeInfo: Static classes that are returned by typeid.
3373 //
3374 // CompleteObjectLocator: Referenced by vftables. They contain information
3375 // required for dynamic casting, including OffsetFromTop. They also contain
3376 // a reference to the TypeInfo for the type and a reference to the
3377 // CompleteHierarchyDescriptor for the type.
3378 //
3379 // ClassHierarchyDescriptor: Contains information about a class hierarchy.
3380 // Used during dynamic_cast to walk a class hierarchy. References a base
3381 // class array and the size of said array.
3382 //
3383 // BaseClassArray: Contains a list of classes in a hierarchy. BaseClassArray is
3384 // somewhat of a misnomer because the most derived class is also in the list
3385 // as well as multiple copies of virtual bases (if they occur multiple times
3386 // in the hierarchy.) The BaseClassArray contains one BaseClassDescriptor for
3387 // every path in the hierarchy, in pre-order depth first order. Note, we do
3388 // not declare a specific llvm type for BaseClassArray, it's merely an array
3389 // of BaseClassDescriptor pointers.
3390 //
3391 // BaseClassDescriptor: Contains information about a class in a class hierarchy.
3392 // BaseClassDescriptor is also somewhat of a misnomer for the same reason that
3393 // BaseClassArray is. It contains information about a class within a
3394 // hierarchy such as: is this base is ambiguous and what is its offset in the
3395 // vbtable. The names of the BaseClassDescriptors have all of their fields
3396 // mangled into them so they can be aggressively deduplicated by the linker.
3397 
3398 static llvm::GlobalVariable *getTypeInfoVTable(CodeGenModule &CGM) {
3399  StringRef MangledName("??_7type_info@@6B@");
3400  if (auto VTable = CGM.getModule().getNamedGlobal(MangledName))
3401  return VTable;
3402  return new llvm::GlobalVariable(CGM.getModule(), CGM.Int8PtrTy,
3403  /*Constant=*/true,
3405  /*Initializer=*/nullptr, MangledName);
3406 }
3407 
3408 namespace {
3409 
3410 /// A Helper struct that stores information about a class in a class
3411 /// hierarchy. The information stored in these structs struct is used during
3412 /// the generation of ClassHierarchyDescriptors and BaseClassDescriptors.
3413 // During RTTI creation, MSRTTIClasses are stored in a contiguous array with
3414 // implicit depth first pre-order tree connectivity. getFirstChild and
3415 // getNextSibling allow us to walk the tree efficiently.
3416 struct MSRTTIClass {
3417  enum {
3418  IsPrivateOnPath = 1 | 8,
3419  IsAmbiguous = 2,
3420  IsPrivate = 4,
3421  IsVirtual = 16,
3422  HasHierarchyDescriptor = 64
3423  };
3424  MSRTTIClass(const CXXRecordDecl *RD) : RD(RD) {}
3425  uint32_t initialize(const MSRTTIClass *Parent,
3426  const CXXBaseSpecifier *Specifier);
3427 
3428  MSRTTIClass *getFirstChild() { return this + 1; }
3429  static MSRTTIClass *getNextChild(MSRTTIClass *Child) {
3430  return Child + 1 + Child->NumBases;
3431  }
3432 
3433  const CXXRecordDecl *RD, *VirtualRoot;
3434  uint32_t Flags, NumBases, OffsetInVBase;
3435 };
3436 
3437 /// Recursively initialize the base class array.
3438 uint32_t MSRTTIClass::initialize(const MSRTTIClass *Parent,
3439  const CXXBaseSpecifier *Specifier) {
3440  Flags = HasHierarchyDescriptor;
3441  if (!Parent) {
3442  VirtualRoot = nullptr;
3443  OffsetInVBase = 0;
3444  } else {
3445  if (Specifier->getAccessSpecifier() != AS_public)
3446  Flags |= IsPrivate | IsPrivateOnPath;
3447  if (Specifier->isVirtual()) {
3448  Flags |= IsVirtual;
3449  VirtualRoot = RD;
3450  OffsetInVBase = 0;
3451  } else {
3452  if (Parent->Flags & IsPrivateOnPath)
3453  Flags |= IsPrivateOnPath;
3454  VirtualRoot = Parent->VirtualRoot;
3455  OffsetInVBase = Parent->OffsetInVBase + RD->getASTContext()
3457  }
3458  }
3459  NumBases = 0;
3460  MSRTTIClass *Child = getFirstChild();
3461  for (const CXXBaseSpecifier &Base : RD->bases()) {
3462  NumBases += Child->initialize(this, &Base) + 1;
3463  Child = getNextChild(Child);
3464  }
3465  return NumBases;
3466 }
3467 
3468 static llvm::GlobalValue::LinkageTypes getLinkageForRTTI(QualType Ty) {
3469  switch (Ty->getLinkage()) {
3470  case NoLinkage:
3471  case InternalLinkage:
3472  case UniqueExternalLinkage:
3474 
3475  case VisibleNoLinkage:
3476  case ModuleInternalLinkage:
3477  case ModuleLinkage:
3478  case ExternalLinkage:
3479  return llvm::GlobalValue::LinkOnceODRLinkage;
3480  }
3481  llvm_unreachable("Invalid linkage!");
3482 }
3483 
3484 /// An ephemeral helper class for building MS RTTI types. It caches some
3485 /// calls to the module and information about the most derived class in a
3486 /// hierarchy.
3487 struct MSRTTIBuilder {
3488  enum {
3489  HasBranchingHierarchy = 1,
3490  HasVirtualBranchingHierarchy = 2,
3491  HasAmbiguousBases = 4
3492  };
3493 
3494  MSRTTIBuilder(MicrosoftCXXABI &ABI, const CXXRecordDecl *RD)
3495  : CGM(ABI.CGM), Context(CGM.getContext()),
3496  VMContext(CGM.getLLVMContext()), Module(CGM.getModule()), RD(RD),
3497  Linkage(getLinkageForRTTI(CGM.getContext().getTagDeclType(RD))),
3498  ABI(ABI) {}
3499 
3500  llvm::GlobalVariable *getBaseClassDescriptor(const MSRTTIClass &Classes);
3501  llvm::GlobalVariable *
3502  getBaseClassArray(SmallVectorImpl<MSRTTIClass> &Classes);
3503  llvm::GlobalVariable *getClassHierarchyDescriptor();
3504  llvm::GlobalVariable *getCompleteObjectLocator(const VPtrInfo &Info);
3505 
3506  CodeGenModule &CGM;
3507  ASTContext &Context;
3508  llvm::LLVMContext &VMContext;
3509  llvm::Module &Module;
3510  const CXXRecordDecl *RD;
3511  llvm::GlobalVariable::LinkageTypes Linkage;
3512  MicrosoftCXXABI &ABI;
3513 };
3514 
3515 } // namespace
3516 
3517 /// Recursively serializes a class hierarchy in pre-order depth first
3518 /// order.
3520  const CXXRecordDecl *RD) {
3521  Classes.push_back(MSRTTIClass(RD));
3522  for (const CXXBaseSpecifier &Base : RD->bases())
3523  serializeClassHierarchy(Classes, Base.getType()->getAsCXXRecordDecl());
3524 }
3525 
3526 /// Find ambiguity among base classes.
3527 static void
3529  llvm::SmallPtrSet<const CXXRecordDecl *, 8> VirtualBases;
3530  llvm::SmallPtrSet<const CXXRecordDecl *, 8> UniqueBases;
3531  llvm::SmallPtrSet<const CXXRecordDecl *, 8> AmbiguousBases;
3532  for (MSRTTIClass *Class = &Classes.front(); Class <= &Classes.back();) {
3533  if ((Class->Flags & MSRTTIClass::IsVirtual) &&
3534  !VirtualBases.insert(Class->RD).second) {
3535  Class = MSRTTIClass::getNextChild(Class);
3536  continue;
3537  }
3538  if (!UniqueBases.insert(Class->RD).second)
3539  AmbiguousBases.insert(Class->RD);
3540  Class++;
3541  }
3542  if (AmbiguousBases.empty())
3543  return;
3544  for (MSRTTIClass &Class : Classes)
3545  if (AmbiguousBases.count(Class.RD))
3546  Class.Flags |= MSRTTIClass::IsAmbiguous;
3547 }
3548 
3549 llvm::GlobalVariable *MSRTTIBuilder::getClassHierarchyDescriptor() {
3550  SmallString<256> MangledName;
3551  {
3552  llvm::raw_svector_ostream Out(MangledName);
3553  ABI.getMangleContext().mangleCXXRTTIClassHierarchyDescriptor(RD, Out);
3554  }
3555 
3556  // Check to see if we've already declared this ClassHierarchyDescriptor.
3557  if (auto CHD = Module.getNamedGlobal(MangledName))
3558  return CHD;
3559 
3560  // Serialize the class hierarchy and initialize the CHD Fields.
3562  serializeClassHierarchy(Classes, RD);
3563  Classes.front().initialize(/*Parent=*/nullptr, /*Specifier=*/nullptr);
3564  detectAmbiguousBases(Classes);
3565  int Flags = 0;
3566  for (auto Class : Classes) {
3567  if (Class.RD->getNumBases() > 1)
3568  Flags |= HasBranchingHierarchy;
3569  // Note: cl.exe does not calculate "HasAmbiguousBases" correctly. We
3570  // believe the field isn't actually used.
3571  if (Class.Flags & MSRTTIClass::IsAmbiguous)
3572  Flags |= HasAmbiguousBases;
3573  }
3574  if ((Flags & HasBranchingHierarchy) && RD->getNumVBases() != 0)
3575  Flags |= HasVirtualBranchingHierarchy;
3576  // These gep indices are used to get the address of the first element of the
3577  // base class array.
3578  llvm::Value *GEPIndices[] = {llvm::ConstantInt::get(CGM.IntTy, 0),
3579  llvm::ConstantInt::get(CGM.IntTy, 0)};
3580 
3581  // Forward-declare the class hierarchy descriptor
3582  auto Type = ABI.getClassHierarchyDescriptorType();
3583  auto CHD = new llvm::GlobalVariable(Module, Type, /*Constant=*/true, Linkage,
3584  /*Initializer=*/nullptr,
3585  MangledName);
3586  if (CHD->isWeakForLinker())
3587  CHD->setComdat(CGM.getModule().getOrInsertComdat(CHD->getName()));
3588 
3589  auto *Bases = getBaseClassArray(Classes);
3590 
3591  // Initialize the base class ClassHierarchyDescriptor.
3592  llvm::Constant *Fields[] = {
3593  llvm::ConstantInt::get(CGM.IntTy, 0), // reserved by the runtime
3594  llvm::ConstantInt::get(CGM.IntTy, Flags),
3595  llvm::ConstantInt::get(CGM.IntTy, Classes.size()),
3596  ABI.getImageRelativeConstant(llvm::ConstantExpr::getInBoundsGetElementPtr(
3597  Bases->getValueType(), Bases,
3598  llvm::ArrayRef<llvm::Value *>(GEPIndices))),
3599  };
3600  CHD->setInitializer(llvm::ConstantStruct::get(Type, Fields));
3601  return CHD;
3602 }
3603 
3604 llvm::GlobalVariable *
3605 MSRTTIBuilder::getBaseClassArray(SmallVectorImpl<MSRTTIClass> &Classes) {
3606  SmallString<256> MangledName;
3607  {
3608  llvm::raw_svector_ostream Out(MangledName);
3609  ABI.getMangleContext().mangleCXXRTTIBaseClassArray(RD, Out);
3610  }
3611 
3612  // Forward-declare the base class array.
3613  // cl.exe pads the base class array with 1 (in 32 bit mode) or 4 (in 64 bit
3614  // mode) bytes of padding. We provide a pointer sized amount of padding by
3615  // adding +1 to Classes.size(). The sections have pointer alignment and are
3616  // marked pick-any so it shouldn't matter.
3617  llvm::Type *PtrType = ABI.getImageRelativeType(
3618  ABI.getBaseClassDescriptorType()->getPointerTo());
3619  auto *ArrType = llvm::ArrayType::get(PtrType, Classes.size() + 1);
3620  auto *BCA =
3621  new llvm::GlobalVariable(Module, ArrType,
3622  /*Constant=*/true, Linkage,
3623  /*Initializer=*/nullptr, MangledName);
3624  if (BCA->isWeakForLinker())
3625  BCA->setComdat(CGM.getModule().getOrInsertComdat(BCA->getName()));
3626 
3627  // Initialize the BaseClassArray.
3628  SmallVector<llvm::Constant *, 8> BaseClassArrayData;
3629  for (MSRTTIClass &Class : Classes)
3630  BaseClassArrayData.push_back(
3631  ABI.getImageRelativeConstant(getBaseClassDescriptor(Class)));
3632  BaseClassArrayData.push_back(llvm::Constant::getNullValue(PtrType));
3633  BCA->setInitializer(llvm::ConstantArray::get(ArrType, BaseClassArrayData));
3634  return BCA;
3635 }
3636 
3637 llvm::GlobalVariable *
3638 MSRTTIBuilder::getBaseClassDescriptor(const MSRTTIClass &Class) {
3639  // Compute the fields for the BaseClassDescriptor. They are computed up front
3640  // because they are mangled into the name of the object.
3641  uint32_t OffsetInVBTable = 0;
3642  int32_t VBPtrOffset = -1;
3643  if (Class.VirtualRoot) {
3644  auto &VTableContext = CGM.getMicrosoftVTableContext();
3645  OffsetInVBTable = VTableContext.getVBTableIndex(RD, Class.VirtualRoot) * 4;
3646  VBPtrOffset = Context.getASTRecordLayout(RD).getVBPtrOffset().getQuantity();
3647  }
3648 
3649  SmallString<256> MangledName;
3650  {
3651  llvm::raw_svector_ostream Out(MangledName);
3652  ABI.getMangleContext().mangleCXXRTTIBaseClassDescriptor(
3653  Class.RD, Class.OffsetInVBase, VBPtrOffset, OffsetInVBTable,
3654  Class.Flags, Out);
3655  }
3656 
3657  // Check to see if we've already declared this object.
3658  if (auto BCD = Module.getNamedGlobal(MangledName))
3659  return BCD;
3660 
3661  // Forward-declare the base class descriptor.
3662  auto Type = ABI.getBaseClassDescriptorType();
3663  auto BCD =
3664  new llvm::GlobalVariable(Module, Type, /*Constant=*/true, Linkage,
3665  /*Initializer=*/nullptr, MangledName);
3666  if (BCD->isWeakForLinker())
3667  BCD->setComdat(CGM.getModule().getOrInsertComdat(BCD->getName()));
3668 
3669  // Initialize the BaseClassDescriptor.
3670  llvm::Constant *Fields[] = {
3671  ABI.getImageRelativeConstant(
3672  ABI.getAddrOfRTTIDescriptor(Context.getTypeDeclType(Class.RD))),
3673  llvm::ConstantInt::get(CGM.IntTy, Class.NumBases),
3674  llvm::ConstantInt::get(CGM.IntTy, Class.OffsetInVBase),
3675  llvm::ConstantInt::get(CGM.IntTy, VBPtrOffset),
3676  llvm::ConstantInt::get(CGM.IntTy, OffsetInVBTable),
3677  llvm::ConstantInt::get(CGM.IntTy, Class.Flags),
3678  ABI.getImageRelativeConstant(
3679  MSRTTIBuilder(ABI, Class.RD).getClassHierarchyDescriptor()),
3680  };
3681  BCD->setInitializer(llvm::ConstantStruct::get(Type, Fields));
3682  return BCD;
3683 }
3684 
3685 llvm::GlobalVariable *
3686 MSRTTIBuilder::getCompleteObjectLocator(const VPtrInfo &Info) {
3687  SmallString<256> MangledName;
3688  {
3689  llvm::raw_svector_ostream Out(MangledName);
3690  ABI.getMangleContext().mangleCXXRTTICompleteObjectLocator(RD, Info.MangledPath, Out);
3691  }
3692 
3693  // Check to see if we've already computed this complete object locator.
3694  if (auto COL = Module.getNamedGlobal(MangledName))
3695  return COL;
3696 
3697  // Compute the fields of the complete object locator.
3698  int OffsetToTop = Info.FullOffsetInMDC.getQuantity();
3699  int VFPtrOffset = 0;
3700  // The offset includes the vtordisp if one exists.
3701  if (const CXXRecordDecl *VBase = Info.getVBaseWithVPtr())
3702  if (Context.getASTRecordLayout(RD)
3704  .find(VBase)
3705  ->second.hasVtorDisp())
3706  VFPtrOffset = Info.NonVirtualOffset.getQuantity() + 4;
3707 
3708  // Forward-declare the complete object locator.
3709  llvm::StructType *Type = ABI.getCompleteObjectLocatorType();
3710  auto COL = new llvm::GlobalVariable(Module, Type, /*Constant=*/true, Linkage,
3711  /*Initializer=*/nullptr, MangledName);
3712 
3713  // Initialize the CompleteObjectLocator.
3714  llvm::Constant *Fields[] = {
3715  llvm::ConstantInt::get(CGM.IntTy, ABI.isImageRelative()),
3716  llvm::ConstantInt::get(CGM.IntTy, OffsetToTop),
3717  llvm::ConstantInt::get(CGM.IntTy, VFPtrOffset),
3718  ABI.getImageRelativeConstant(
3719  CGM.GetAddrOfRTTIDescriptor(Context.getTypeDeclType(RD))),
3720  ABI.getImageRelativeConstant(getClassHierarchyDescriptor()),
3721  ABI.getImageRelativeConstant(COL),
3722  };
3723  llvm::ArrayRef<llvm::Constant *> FieldsRef(Fields);
3724  if (!ABI.isImageRelative())
3725  FieldsRef = FieldsRef.drop_back();
3726  COL->setInitializer(llvm::ConstantStruct::get(Type, FieldsRef));
3727  if (COL->isWeakForLinker())
3728  COL->setComdat(CGM.getModule().getOrInsertComdat(COL->getName()));
3729  return COL;
3730 }
3731 
3733  bool &IsConst, bool &IsVolatile,
3734  bool &IsUnaligned) {
3735  T = Context.getExceptionObjectType(T);
3736 
3737  // C++14 [except.handle]p3:
3738  // A handler is a match for an exception object of type E if [...]
3739  // - the handler is of type cv T or const T& where T is a pointer type and
3740  // E is a pointer type that can be converted to T by [...]
3741  // - a qualification conversion
3742  IsConst = false;
3743  IsVolatile = false;
3744  IsUnaligned = false;
3745  QualType PointeeType = T->getPointeeType();
3746  if (!PointeeType.isNull()) {
3747  IsConst = PointeeType.isConstQualified();
3748  IsVolatile = PointeeType.isVolatileQualified();
3749  IsUnaligned = PointeeType.getQualifiers().hasUnaligned();
3750  }
3751 
3752  // Member pointer types like "const int A::*" are represented by having RTTI
3753  // for "int A::*" and separately storing the const qualifier.
3754  if (const auto *MPTy = T->getAs<MemberPointerType>())
3755  T = Context.getMemberPointerType(PointeeType.getUnqualifiedType(),
3756  MPTy->getClass());
3757 
3758  // Pointer types like "const int * const *" are represented by having RTTI
3759  // for "const int **" and separately storing the const qualifier.
3760  if (T->isPointerType())
3761  T = Context.getPointerType(PointeeType.getUnqualifiedType());
3762 
3763  return T;
3764 }
3765 
3767 MicrosoftCXXABI::getAddrOfCXXCatchHandlerType(QualType Type,
3768  QualType CatchHandlerType) {
3769  // TypeDescriptors for exceptions never have qualified pointer types,
3770  // qualifiers are stored separately in order to support qualification
3771  // conversions.
3772  bool IsConst, IsVolatile, IsUnaligned;
3773  Type =
3774  decomposeTypeForEH(getContext(), Type, IsConst, IsVolatile, IsUnaligned);
3775 
3776  bool IsReference = CatchHandlerType->isReferenceType();
3777 
3778  uint32_t Flags = 0;
3779  if (IsConst)
3780  Flags |= 1;
3781  if (IsVolatile)
3782  Flags |= 2;
3783  if (IsUnaligned)
3784  Flags |= 4;
3785  if (IsReference)
3786  Flags |= 8;
3787 
3788  return CatchTypeInfo{getAddrOfRTTIDescriptor(Type)->stripPointerCasts(),
3789  Flags};
3790 }
3791 
3792 /// Gets a TypeDescriptor. Returns a llvm::Constant * rather than a
3793 /// llvm::GlobalVariable * because different type descriptors have different
3794 /// types, and need to be abstracted. They are abstracting by casting the
3795 /// address to an Int8PtrTy.
3796 llvm::Constant *MicrosoftCXXABI::getAddrOfRTTIDescriptor(QualType Type) {
3797  SmallString<256> MangledName;
3798  {
3799  llvm::raw_svector_ostream Out(MangledName);
3800  getMangleContext().mangleCXXRTTI(Type, Out);
3801  }
3802 
3803  // Check to see if we've already declared this TypeDescriptor.
3804  if (llvm::GlobalVariable *GV = CGM.getModule().getNamedGlobal(MangledName))
3805  return llvm::ConstantExpr::getBitCast(GV, CGM.Int8PtrTy);
3806 
3807  // Note for the future: If we would ever like to do deferred emission of
3808  // RTTI, check if emitting vtables opportunistically need any adjustment.
3809 
3810  // Compute the fields for the TypeDescriptor.
3811  SmallString<256> TypeInfoString;
3812  {
3813  llvm::raw_svector_ostream Out(TypeInfoString);
3814  getMangleContext().mangleCXXRTTIName(Type, Out);
3815  }
3816 
3817  // Declare and initialize the TypeDescriptor.
3818  llvm::Constant *Fields[] = {
3819  getTypeInfoVTable(CGM), // VFPtr
3820  llvm::ConstantPointerNull::get(CGM.Int8PtrTy), // Runtime data
3821  llvm::ConstantDataArray::getString(CGM.getLLVMContext(), TypeInfoString)};
3822  llvm::StructType *TypeDescriptorType =
3823  getTypeDescriptorType(TypeInfoString);
3824  auto *Var = new llvm::GlobalVariable(
3825  CGM.getModule(), TypeDescriptorType, /*Constant=*/false,
3826  getLinkageForRTTI(Type),
3827  llvm::ConstantStruct::get(TypeDescriptorType, Fields),
3828  MangledName);
3829  if (Var->isWeakForLinker())
3830  Var->setComdat(CGM.getModule().getOrInsertComdat(Var->getName()));
3831  return llvm::ConstantExpr::getBitCast(Var, CGM.Int8PtrTy);
3832 }
3833 
3834 /// Gets or a creates a Microsoft CompleteObjectLocator.
3835 llvm::GlobalVariable *
3836 MicrosoftCXXABI::getMSCompleteObjectLocator(const CXXRecordDecl *RD,
3837  const VPtrInfo &Info) {
3838  return MSRTTIBuilder(*this, RD).getCompleteObjectLocator(Info);
3839 }
3840 
3841 void MicrosoftCXXABI::emitCXXStructor(GlobalDecl GD) {
3842  if (auto *ctor = dyn_cast<CXXConstructorDecl>(GD.getDecl())) {
3843  // There are no constructor variants, always emit the complete destructor.
3844  llvm::Function *Fn =
3846  CGM.maybeSetTrivialComdat(*ctor, *Fn);
3847  return;
3848  }
3849 
3850  auto *dtor = cast<CXXDestructorDecl>(GD.getDecl());
3851 
3852  // Emit the base destructor if the base and complete (vbase) destructors are
3853  // equivalent. This effectively implements -mconstructor-aliases as part of
3854  // the ABI.
3855  if (GD.getDtorType() == Dtor_Complete &&
3856  dtor->getParent()->getNumVBases() == 0)
3857  GD = GD.getWithDtorType(Dtor_Base);
3858 
3859  // The base destructor is equivalent to the base destructor of its
3860  // base class if there is exactly one non-virtual base class with a
3861  // non-trivial destructor, there are no fields with a non-trivial
3862  // destructor, and the body of the destructor is trivial.
3863  if (GD.getDtorType() == Dtor_Base && !CGM.TryEmitBaseDestructorAsAlias(dtor))
3864  return;
3865 
3866  llvm::Function *Fn = CGM.codegenCXXStructor(GD);
3867  if (Fn->isWeakForLinker())
3868  Fn->setComdat(CGM.getModule().getOrInsertComdat(Fn->getName()));
3869 }
3870 
3871 llvm::Function *
3872 MicrosoftCXXABI::getAddrOfCXXCtorClosure(const CXXConstructorDecl *CD,
3873  CXXCtorType CT) {
3874  assert(CT == Ctor_CopyingClosure || CT == Ctor_DefaultClosure);
3875 
3876  // Calculate the mangled name.
3877  SmallString<256> ThunkName;
3878  llvm::raw_svector_ostream Out(ThunkName);
3879  getMangleContext().mangleCXXCtor(CD, CT, Out);
3880 
3881  // If the thunk has been generated previously, just return it.
3882  if (llvm::GlobalValue *GV = CGM.getModule().getNamedValue(ThunkName))
3883  return cast<llvm::Function>(GV);
3884 
3885  // Create the llvm::Function.
3886  const CGFunctionInfo &FnInfo = CGM.getTypes().arrangeMSCtorClosure(CD, CT);
3887  llvm::FunctionType *ThunkTy = CGM.getTypes().GetFunctionType(FnInfo);
3888  const CXXRecordDecl *RD = CD->getParent();
3889  QualType RecordTy = getContext().getRecordType(RD);
3890  llvm::Function *ThunkFn = llvm::Function::Create(
3891  ThunkTy, getLinkageForRTTI(RecordTy), ThunkName.str(), &CGM.getModule());
3892  ThunkFn->setCallingConv(static_cast<llvm::CallingConv::ID>(
3893  FnInfo.getEffectiveCallingConvention()));
3894  if (ThunkFn->isWeakForLinker())
3895  ThunkFn->setComdat(CGM.getModule().getOrInsertComdat(ThunkFn->getName()));
3896  bool IsCopy = CT == Ctor_CopyingClosure;
3897 
3898  // Start codegen.
3899  CodeGenFunction CGF(CGM);
3900  CGF.CurGD = GlobalDecl(CD, Ctor_Complete);
3901 
3902  // Build FunctionArgs.
3903  FunctionArgList FunctionArgs;
3904 
3905  // A constructor always starts with a 'this' pointer as its first argument.
3906  buildThisParam(CGF, FunctionArgs);
3907 
3908  // Following the 'this' pointer is a reference to the source object that we
3909  // are copying from.
3910  ImplicitParamDecl SrcParam(
3911  getContext(), /*DC=*/nullptr, SourceLocation(),
3912  &getContext().Idents.get("src"),
3913  getContext().getLValueReferenceType(RecordTy,
3914  /*SpelledAsLValue=*/true),
3916  if (IsCopy)
3917  FunctionArgs.push_back(&SrcParam);
3918 
3919  // Constructors for classes which utilize virtual bases have an additional
3920  // parameter which indicates whether or not it is being delegated to by a more
3921  // derived constructor.
3922  ImplicitParamDecl IsMostDerived(getContext(), /*DC=*/nullptr,
3923  SourceLocation(),
3924  &getContext().Idents.get("is_most_derived"),
3925  getContext().IntTy, ImplicitParamDecl::Other);
3926  // Only add the parameter to the list if the class has virtual bases.
3927  if (RD->getNumVBases() > 0)
3928  FunctionArgs.push_back(&IsMostDerived);
3929 
3930  // Start defining the function.
3931  auto NL = ApplyDebugLocation::CreateEmpty(CGF);
3932  CGF.StartFunction(GlobalDecl(), FnInfo.getReturnType(), ThunkFn, FnInfo,
3933  FunctionArgs, CD->getLocation(), SourceLocation());
3934  // Create a scope with an artificial location for the body of this function.
3935  auto AL = ApplyDebugLocation::CreateArtificial(CGF);
3936  setCXXABIThisValue(CGF, loadIncomingCXXThis(CGF));
3937  llvm::Value *This = getThisValue(CGF);
3938 
3939  llvm::Value *SrcVal =
3940  IsCopy ? CGF.Builder.CreateLoad(CGF.GetAddrOfLocalVar(&SrcParam), "src")
3941  : nullptr;
3942 
3943  CallArgList Args;
3944 
3945  // Push the this ptr.
3946  Args.add(RValue::get(This), CD->getThisType());
3947 
3948  // Push the src ptr.
3949  if (SrcVal)
3950  Args.add(RValue::get(SrcVal), SrcParam.getType());
3951 
3952  // Add the rest of the default arguments.
3954  ArrayRef<ParmVarDecl *> params = CD->parameters().drop_front(IsCopy ? 1 : 0);
3955  for (const ParmVarDecl *PD : params) {
3956  assert(PD->hasDefaultArg() && "ctor closure lacks default args");
3957  ArgVec.push_back(PD->getDefaultArg());
3958  }
3959 
3960  CodeGenFunction::RunCleanupsScope Cleanups(CGF);
3961 
3962  const auto *FPT = CD->getType()->castAs<FunctionProtoType>();
3963  CGF.EmitCallArgs(Args, FPT, llvm::makeArrayRef(ArgVec), CD, IsCopy ? 1 : 0);
3964 
3965  // Insert any ABI-specific implicit constructor arguments.
3966  AddedStructorArgs ExtraArgs =
3967  addImplicitConstructorArgs(CGF, CD, Ctor_Complete,
3968  /*ForVirtualBase=*/false,
3969  /*Delegating=*/false, Args);
3970  // Call the destructor with our arguments.
3971  llvm::Constant *CalleePtr =
3973  CGCallee Callee =
3974  CGCallee::forDirect(CalleePtr, GlobalDecl(CD, Ctor_Complete));
3975  const CGFunctionInfo &CalleeInfo = CGM.getTypes().arrangeCXXConstructorCall(
3976  Args, CD, Ctor_Complete, ExtraArgs.Prefix, ExtraArgs.Suffix);
3977  CGF.EmitCall(CalleeInfo, Callee, ReturnValueSlot(), Args);
3978 
3979  Cleanups.ForceCleanup();
3980 
3981  // Emit the ret instruction, remove any temporary instructions created for the
3982  // aid of CodeGen.
3984 
3985  return ThunkFn;
3986 }
3987 
3988 llvm::Constant *MicrosoftCXXABI::getCatchableType(QualType T,
3989  uint32_t NVOffset,
3990  int32_t VBPtrOffset,
3991  uint32_t VBIndex) {
3992  assert(!T->isReferenceType());
3993 
3994  CXXRecordDecl *RD = T->getAsCXXRecordDecl();
3995  const CXXConstructorDecl *CD =
3996  RD ? CGM.getContext().getCopyConstructorForExceptionObject(RD) : nullptr;
3998  if (CD)
3999  if (!hasDefaultCXXMethodCC(getContext(), CD) || CD->getNumParams() != 1)
4000  CT = Ctor_CopyingClosure;
4001 
4002  uint32_t Size = getContext().getTypeSizeInChars(T).getQuantity();
4003  SmallString<256> MangledName;
4004  {
4005  llvm::raw_svector_ostream Out(MangledName);
4006  getMangleContext().mangleCXXCatchableType(T, CD, CT, Size, NVOffset,
4007  VBPtrOffset, VBIndex, Out);
4008  }
4009  if (llvm::GlobalVariable *GV = CGM.getModule().getNamedGlobal(MangledName))
4010  return getImageRelativeConstant(GV);
4011 
4012  // The TypeDescriptor is used by the runtime to determine if a catch handler
4013  // is appropriate for the exception object.
4014  llvm::Constant *TD = getImageRelativeConstant(getAddrOfRTTIDescriptor(T));
4015 
4016  // The runtime is responsible for calling the copy constructor if the
4017  // exception is caught by value.
4018  llvm::Constant *CopyCtor;
4019  if (CD) {
4020  if (CT == Ctor_CopyingClosure)
4021  CopyCtor = getAddrOfCXXCtorClosure(CD, Ctor_CopyingClosure);
4022  else
4023  CopyCtor = CGM.getAddrOfCXXStructor(GlobalDecl(CD, Ctor_Complete));
4024 
4025  CopyCtor = llvm::ConstantExpr::getBitCast(CopyCtor, CGM.Int8PtrTy);
4026  } else {
4027  CopyCtor = llvm::Constant::getNullValue(CGM.Int8PtrTy);
4028  }
4029  CopyCtor = getImageRelativeConstant(CopyCtor);
4030 
4031  bool IsScalar = !RD;
4032  bool HasVirtualBases = false;
4033  bool IsStdBadAlloc = false; // std::bad_alloc is special for some reason.
4034  QualType PointeeType = T;
4035  if (T->isPointerType())
4036  PointeeType = T->getPointeeType();
4037  if (const CXXRecordDecl *RD = PointeeType->getAsCXXRecordDecl()) {
4038  HasVirtualBases = RD->getNumVBases() > 0;
4039  if (IdentifierInfo *II = RD->getIdentifier())
4040  IsStdBadAlloc = II->isStr("bad_alloc") && RD->isInStdNamespace();
4041  }
4042 
4043  // Encode the relevant CatchableType properties into the Flags bitfield.
4044  // FIXME: Figure out how bits 2 or 8 can get set.
4045  uint32_t Flags = 0;
4046  if (IsScalar)
4047  Flags |= 1;
4048  if (HasVirtualBases)
4049  Flags |= 4;
4050  if (IsStdBadAlloc)
4051  Flags |= 16;
4052 
4053  llvm::Constant *Fields[] = {
4054  llvm::ConstantInt::get(CGM.IntTy, Flags), // Flags
4055  TD, // TypeDescriptor
4056  llvm::ConstantInt::get(CGM.IntTy, NVOffset), // NonVirtualAdjustment
4057  llvm::ConstantInt::get(CGM.IntTy, VBPtrOffset), // OffsetToVBPtr
4058  llvm::ConstantInt::get(CGM.IntTy, VBIndex), // VBTableIndex
4059  llvm::ConstantInt::get(CGM.IntTy, Size), // Size
4060  CopyCtor // CopyCtor
4061  };
4062  llvm::StructType *CTType = getCatchableTypeType();
4063  auto *GV = new llvm::GlobalVariable(
4064  CGM.getModule(), CTType, /*Constant=*/true, getLinkageForRTTI(T),
4065  llvm::ConstantStruct::get(CTType, Fields), MangledName);
4066  GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
4067  GV->setSection(".xdata");
4068  if (GV->isWeakForLinker())
4069  GV->setComdat(CGM.getModule().getOrInsertComdat(GV->getName()));
4070  return getImageRelativeConstant(GV);
4071 }
4072 
4073 llvm::GlobalVariable *MicrosoftCXXABI::getCatchableTypeArray(QualType T) {
4074  assert(!T->isReferenceType());
4075 
4076  // See if we've already generated a CatchableTypeArray for this type before.
4077  llvm::GlobalVariable *&CTA = CatchableTypeArrays[T];
4078  if (CTA)
4079  return CTA;
4080 
4081  // Ensure that we don't have duplicate entries in our CatchableTypeArray by
4082  // using a SmallSetVector. Duplicates may arise due to virtual bases
4083  // occurring more than once in the hierarchy.
4085 
4086  // C++14 [except.handle]p3:
4087  // A handler is a match for an exception object of type E if [...]
4088  // - the handler is of type cv T or cv T& and T is an unambiguous public
4089  // base class of E, or
4090  // - the handler is of type cv T or const T& where T is a pointer type and
4091  // E is a pointer type that can be converted to T by [...]
4092  // - a standard pointer conversion (4.10) not involving conversions to
4093  // pointers to private or protected or ambiguous classes
4094  const CXXRecordDecl *MostDerivedClass = nullptr;
4095  bool IsPointer = T->isPointerType();
4096  if (IsPointer)
4097  MostDerivedClass = T->getPointeeType()->getAsCXXRecordDecl();
4098  else
4099  MostDerivedClass = T->getAsCXXRecordDecl();
4100 
4101  // Collect all the unambiguous public bases of the MostDerivedClass.
4102  if (MostDerivedClass) {
4103  const ASTContext &Context = getContext();
4104  const ASTRecordLayout &MostDerivedLayout =
4105  Context.getASTRecordLayout(MostDerivedClass);
4106  MicrosoftVTableContext &VTableContext = CGM.getMicrosoftVTableContext();
4108  serializeClassHierarchy(Classes, MostDerivedClass);
4109  Classes.front().initialize(/*Parent=*/nullptr, /*Specifier=*/nullptr);
4110  detectAmbiguousBases(Classes);
4111  for (const MSRTTIClass &Class : Classes) {
4112  // Skip any ambiguous or private bases.
4113  if (Class.Flags &
4114  (MSRTTIClass::IsPrivateOnPath | MSRTTIClass::IsAmbiguous))
4115  continue;
4116  // Write down how to convert from a derived pointer to a base pointer.
4117  uint32_t OffsetInVBTable = 0;
4118  int32_t VBPtrOffset = -1;
4119  if (Class.VirtualRoot) {
4120  OffsetInVBTable =
4121  VTableContext.getVBTableIndex(MostDerivedClass, Class.VirtualRoot)*4;
4122  VBPtrOffset = MostDerivedLayout.getVBPtrOffset().getQuantity();
4123  }
4124 
4125  // Turn our record back into a pointer if the exception object is a
4126  // pointer.
4127  QualType RTTITy = QualType(Class.RD->getTypeForDecl(), 0);
4128  if (IsPointer)
4129  RTTITy = Context.getPointerType(RTTITy);
4130  CatchableTypes.insert(getCatchableType(RTTITy, Class.OffsetInVBase,
4131  VBPtrOffset, OffsetInVBTable));
4132  }
4133  }
4134 
4135  // C++14 [except.handle]p3:
4136  // A handler is a match for an exception object of type E if
4137  // - The handler is of type cv T or cv T& and E and T are the same type
4138  // (ignoring the top-level cv-qualifiers)
4139  CatchableTypes.insert(getCatchableType(T));
4140 
4141  // C++14 [except.handle]p3:
4142  // A handler is a match for an exception object of type E if
4143  // - the handler is of type cv T or const T& where T is a pointer type and
4144  // E is a pointer type that can be converted to T by [...]
4145  // - a standard pointer conversion (4.10) not involving conversions to
4146  // pointers to private or protected or ambiguous classes
4147  //
4148  // C++14 [conv.ptr]p2:
4149  // A prvalue of type "pointer to cv T," where T is an object type, can be
4150  // converted to a prvalue of type "pointer to cv void".
4151  if (IsPointer && T->getPointeeType()->isObjectType())
4152  CatchableTypes.insert(getCatchableType(getContext().VoidPtrTy));
4153 
4154  // C++14 [except.handle]p3:
4155  // A handler is a match for an exception object of type E if [...]
4156  // - the handler is of type cv T or const T& where T is a pointer or
4157  // pointer to member type and E is std::nullptr_t.
4158  //
4159  // We cannot possibly list all possible pointer types here, making this
4160  // implementation incompatible with the standard. However, MSVC includes an
4161  // entry for pointer-to-void in this case. Let's do the same.
4162  if (T->isNullPtrType())
4163  CatchableTypes.insert(getCatchableType(getContext().VoidPtrTy));
4164 
4165  uint32_t NumEntries = CatchableTypes.size();
4166  llvm::Type *CTType =
4167  getImageRelativeType(getCatchableTypeType()->getPointerTo());
4168  llvm::ArrayType *AT = llvm::ArrayType::get(CTType, NumEntries);
4169  llvm::StructType *CTAType = getCatchableTypeArrayType(NumEntries);
4170  llvm::Constant *Fields[] = {
4171  llvm::ConstantInt::get(CGM.IntTy, NumEntries), // NumEntries
4172  llvm::ConstantArray::get(
4173  AT, llvm::makeArrayRef(CatchableTypes.begin(),
4174  CatchableTypes.end())) // CatchableTypes
4175  };
4176  SmallString<256> MangledName;
4177  {
4178  llvm::raw_svector_ostream Out(MangledName);
4179  getMangleContext().mangleCXXCatchableTypeArray(T, NumEntries, Out);
4180  }
4181  CTA = new llvm::GlobalVariable(
4182  CGM.getModule(), CTAType, /*Constant=*/true, getLinkageForRTTI(T),
4183  llvm::ConstantStruct::get(CTAType, Fields), MangledName);
4184  CTA->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
4185  CTA->setSection(".xdata");
4186  if (CTA->isWeakForLinker())
4187  CTA->setComdat(CGM.getModule().getOrInsertComdat(CTA->getName()));
4188  return CTA;
4189 }
4190 
4191 llvm::GlobalVariable *MicrosoftCXXABI::getThrowInfo(QualType T) {
4192  bool IsConst, IsVolatile, IsUnaligned;
4193  T = decomposeTypeForEH(getContext(), T, IsConst, IsVolatile, IsUnaligned);
4194 
4195  // The CatchableTypeArray enumerates the various (CV-unqualified) types that
4196  // the exception object may be caught as.
4197  llvm::GlobalVariable *CTA = getCatchableTypeArray(T);
4198  // The first field in a CatchableTypeArray is the number of CatchableTypes.
4199  // This is used as a component of the mangled name which means that we need to
4200  // know what it is in order to see if we have previously generated the
4201  // ThrowInfo.
4202  uint32_t NumEntries =
4203  cast<llvm::ConstantInt>(CTA->getInitializer()->getAggregateElement(0U))
4204  ->getLimitedValue();
4205 
4206  SmallString<256> MangledName;
4207  {
4208  llvm::raw_svector_ostream Out(MangledName);
4209  getMangleContext().mangleCXXThrowInfo(T, IsConst, IsVolatile, IsUnaligned,
4210  NumEntries, Out);
4211  }
4212 
4213  // Reuse a previously generated ThrowInfo if we have generated an appropriate
4214  // one before.
4215  if (llvm::GlobalVariable *GV = CGM.getModule().getNamedGlobal(MangledName))
4216  return GV;
4217 
4218  // The RTTI TypeDescriptor uses an unqualified type but catch clauses must
4219  // be at least as CV qualified. Encode this requirement into the Flags
4220  // bitfield.
4221  uint32_t Flags = 0;
4222  if (IsConst)
4223  Flags |= 1;
4224  if (IsVolatile)
4225  Flags |= 2;
4226  if (IsUnaligned)
4227  Flags |= 4;
4228 
4229  // The cleanup-function (a destructor) must be called when the exception
4230  // object's lifetime ends.
4231  llvm::Constant *CleanupFn = llvm::Constant::getNullValue(CGM.Int8PtrTy);
4232  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4233  if (CXXDestructorDecl *DtorD = RD->getDestructor())
4234  if (!DtorD->isTrivial())
4235  CleanupFn = llvm::ConstantExpr::getBitCast(
4237  CGM.Int8PtrTy);
4238  // This is unused as far as we can tell, initialize it to null.
4239  llvm::Constant *ForwardCompat =
4240  getImageRelativeConstant(llvm::Constant::getNullValue(CGM.Int8PtrTy));
4241  llvm::Constant *PointerToCatchableTypes = getImageRelativeConstant(
4242  llvm::ConstantExpr::getBitCast(CTA, CGM.Int8PtrTy));
4243  llvm::StructType *TIType = getThrowInfoType();
4244  llvm::Constant *Fields[] = {
4245  llvm::ConstantInt::get(CGM.IntTy, Flags), // Flags
4246  getImageRelativeConstant(CleanupFn), // CleanupFn
4247  ForwardCompat, // ForwardCompat
4248  PointerToCatchableTypes // CatchableTypeArray
4249  };
4250  auto *GV = new llvm::GlobalVariable(
4251  CGM.getModule(), TIType, /*Constant=*/true, getLinkageForRTTI(T),
4252  llvm::ConstantStruct::get(TIType, Fields), StringRef(MangledName));
4253  GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
4254  GV->setSection(".xdata");
4255  if (GV->isWeakForLinker())
4256  GV->setComdat(CGM.getModule().getOrInsertComdat(GV->getName()));
4257  return GV;
4258 }
4259 
4260 void MicrosoftCXXABI::emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) {
4261  const Expr *SubExpr = E->getSubExpr();
4262  QualType ThrowType = SubExpr->getType();
4263  // The exception object lives on the stack and it's address is passed to the
4264  // runtime function.
4265  Address AI = CGF.CreateMemTemp(ThrowType);
4266  CGF.EmitAnyExprToMem(SubExpr, AI, ThrowType.getQualifiers(),
4267  /*IsInit=*/true);
4268 
4269  // The so-called ThrowInfo is used to describe how the exception object may be
4270  // caught.
4271  llvm::GlobalVariable *TI = getThrowInfo(ThrowType);
4272 
4273  // Call into the runtime to throw the exception.
4274  llvm::Value *Args[] = {
4275  CGF.Builder.CreateBitCast(AI.getPointer(), CGM.Int8PtrTy),
4276  TI
4277  };
4279 }
4280 
4281 std::pair<llvm::Value *, const CXXRecordDecl *>
4282 MicrosoftCXXABI::LoadVTablePtr(CodeGenFunction &CGF, Address This,
4283  const CXXRecordDecl *RD) {
4284  std::tie(This, std::ignore, RD) =
4285  performBaseAdjustment(CGF, This, QualType(RD->getTypeForDecl(), 0));
4286  return {CGF.GetVTablePtr(This, CGM.Int8PtrTy, RD), RD};
4287 }
ReturnValueSlot - Contains the address where the return value of a function can be stored...
Definition: CGCall.h:363
void EmitCXXGuardedInitBranch(llvm::Value *NeedsInit, llvm::BasicBlock *InitBlock, llvm::BasicBlock *NoInitBlock, GuardKind Kind, const VarDecl *D)
Emit a branch to select whether or not to perform guarded initialization.
Definition: CGDeclCXX.cpp:286
struct clang::ReturnAdjustment::VirtualAdjustment::@134 Microsoft
static QualType decomposeTypeForEH(ASTContext &Context, QualType T, bool &IsConst, bool &IsVolatile, bool &IsUnaligned)
llvm::IntegerType * IntTy
int
void setSRetAfterThis(bool AfterThis)
External linkage, which indicates that the entity can be referred to from other translation units...
Definition: Linkage.h:59
Other implicit parameter.
Definition: Decl.h:1524
Complete object ctor.
Definition: ABI.h:25
A (possibly-)qualified type.
Definition: Type.h:643
static llvm::CallBase * emitRTtypeidCall(CodeGenFunction &CGF, llvm::Value *Argument)
base_class_range bases()
Definition: DeclCXX.h:825
llvm::Type * ConvertTypeForMem(QualType T)
unsigned getNumBases() const
Retrieves the number of base classes of this class.
Definition: DeclCXX.h:819
uint32_t VBPtrOffset
The offset (in bytes) of the vbptr, relative to the beginning of the derived class.
Definition: ABI.h:60
Internal linkage according to the Modules TS, but can be referred to from other translation units ind...
Definition: Linkage.h:49
const Expr * getSubExpr() const
Definition: ExprCXX.h:1066
Address CreateMemTemp(QualType T, const Twine &Name="tmp", Address *Alloca=nullptr)
CreateMemTemp - Create a temporary memory object of the given type, with appropriate alignmen and cas...
Definition: CGExpr.cpp:138
bool isEmpty() const
Definition: ABI.h:154
llvm::LLVMContext & getLLVMContext()
static void detectAmbiguousBases(SmallVectorImpl< MSRTTIClass > &Classes)
Find ambiguity among base classes.
CXXDtorType getDtorType() const
Definition: GlobalDecl.h:83
The standard implementation of ConstantInitBuilder used in Clang.
const ASTRecordLayout & getASTRecordLayout(const RecordDecl *D) const
Get or compute information about the layout of the specified record (struct/union/class) D...
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:505
const llvm::Triple & getTriple() const
Returns the target triple of the primary target.
Definition: TargetInfo.h:983
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:232
No linkage, which means that the entity is unique and can only be referred to from within its scope...
Definition: Linkage.h:26
unsigned getNumVBases() const
Retrieves the number of virtual base classes of this class.
Definition: DeclCXX.h:840
QualType getThisType() const
Returns the type of the this pointer.
Definition: DeclCXX.cpp:2265
bool isEmpty() const
Definition: ABI.h:86
const Type * getTypeForDecl() const
Definition: Decl.h:2929
llvm::Constant * getAddrOfCXXStructor(GlobalDecl GD, const CGFunctionInfo *FnInfo=nullptr, llvm::FunctionType *FnType=nullptr, bool DontDefer=false, ForDefinition_t IsForDefinition=NotForDefinition)
Return the address of the constructor/destructor of the given type.
bool isVariadic() const
Whether this function prototype is variadic.
Definition: Type.h:4020
CharUnits VFPtrOffset
This is the offset of the vfptr from the start of the last vbase, or the complete type if there are n...
const CGFunctionInfo & arrangeCXXMethodType(const CXXRecordDecl *RD, const FunctionProtoType *FTP, const CXXMethodDecl *MD)
Arrange the argument and result information for a call to an unknown C++ non-static member function o...
Definition: CGCall.cpp:250
bool isVirtual() const
Definition: DeclCXX.h:2157
const Decl * CurCodeDecl
CurCodeDecl - This is the inner-most code context, which includes blocks.
bool isVirtual() const
Determines whether the base class is a virtual base class (or not).
Definition: DeclCXX.h:245
bool isPOD() const
Whether this class is a POD-type (C++ [class]p4)
Definition: DeclCXX.h:1317
The base class of the type hierarchy.
Definition: Type.h:1418
int64_t NonVirtual
The non-virtual adjustment from the derived object to its nearest virtual base.
Definition: ABI.h:110
DiagnosticBuilder Report(SourceLocation Loc, unsigned DiagID)
Issue the message to the client.
Definition: Diagnostic.h:1296
bool isZero() const
isZero - Test whether the quantity equals zero.
Definition: CharUnits.h:115
const NestedNameSpecifier * Specifier
bool isFuncTypeConvertible(const FunctionType *FT)
isFuncTypeConvertible - Utility to check whether a function type can be converted to an LLVM type (i...
Linkage getLinkage() const
Determine the linkage of this type.
Definition: Type.cpp:3692
BasePath MangledPath
The bases from the inheritance path that got used to mangle the vbtable name.
llvm::IntegerType * Int8Ty
i8, i16, i32, and i64
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2566
bool TryEmitBaseDestructorAsAlias(const CXXDestructorDecl *D)
Try to emit a base destructor as an alias to its primary base-class destructor.
Definition: CGCXX.cpp:33
static llvm::FunctionCallee getInitThreadFooterFn(CodeGenModule &CGM)
Default closure variant of a ctor.
Definition: ABI.h:29
MSInheritanceAttr::Spelling getMSInheritanceModel() const
Returns the inheritance model used for this record.
bool isDefaultConstructor() const
Whether this constructor is a default constructor (C++ [class.ctor]p5), which can be used to default-...
Definition: DeclCXX.cpp:2445
const CXXBaseSpecifier *const * path_const_iterator
Definition: Expr.h:3190
Address GetAddrOfLocalVar(const VarDecl *VD)
GetAddrOfLocalVar - Return the address of a local variable.
GlobalDecl getWithCtorType(CXXCtorType Type)
Definition: GlobalDecl.h:122
Represents a variable declaration or definition.
Definition: Decl.h:812
Address getObjectAddress(CodeGenFunction &CGF) const
Returns the address of the object within this declaration.
const CXXRecordDecl * VBase
If nonnull, holds the last vbase which contains the vfptr that the method definition is adjusted to...
const internal::VariadicDynCastAllOfMatcher< Stmt, Expr > expr
Matches expressions.
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6818
A this pointer adjustment.
Definition: ABI.h:107
DiagnosticsEngine & getDiags() const
Address CreateConstInBoundsByteGEP(Address Addr, CharUnits Offset, const llvm::Twine &Name="")
Given a pointer to i8, adjust it by a given constant offset.
Definition: CGBuilder.h:244
QualType getMemberPointerType(QualType T, const Type *Cls) const
Return the uniqued reference to the type for a member pointer to the specified type in the specified ...
llvm::Value * getPointer() const
Definition: Address.h:37
A C++ throw-expression (C++ [except.throw]).
Definition: ExprCXX.h:1044
bool hasDefinition() const
Definition: DeclCXX.h:778
Represents a parameter to a function.
Definition: Decl.h:1564
Linkage
Describes the different kinds of linkage (C++ [basic.link], C99 6.2.2) that an entity may have...
Definition: Linkage.h:23
unsigned getAddressSpace() const
Return the address space that this address resides in.
Definition: Address.h:56
void add(RValue rvalue, QualType type)
Definition: CGCall.h:287
const ValueDecl * getMemberPointerDecl() const
Definition: APValue.cpp:772
CharUnits getBaseOffset() const
getBaseOffset - Returns the base class offset.
Definition: BaseSubobject.h:46
int32_t VBOffsetOffset
The offset (in bytes) of the vbase offset in the vbtable.
Definition: ABI.h:131
DeclarationName getDeclName() const
Get the actual, stored name of the declaration, which may be a special name.
Definition: Decl.h:297
One of these records is kept for each identifier that is lexed.
CodeGenFunction - This class organizes the per-function state that is used while generating LLVM code...
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:154
virtual void mangleCXXVFTable(const CXXRecordDecl *Derived, ArrayRef< const CXXRecordDecl *> BasePath, raw_ostream &Out)=0
Mangle vftable symbols.
bool ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD)
Returns whether we should perform a type checked load when loading a virtual function for virtual cal...
Definition: CGClass.cpp:2775
bool isReferenceType() const
Definition: Type.h:6363
Denotes a cleanup that should run when a scope is exited using exceptional control flow (a throw stat...
Definition: EHScopeStack.h:80
A return adjustment.
Definition: ABI.h:41
static CharUnits Zero()
Zero - Construct a CharUnits quantity of zero.
Definition: CharUnits.h:52
CharUnits getVBaseClassOffset(const CXXRecordDecl *VBase) const
getVBaseClassOffset - Get the offset, in chars, for the given base class.
Definition: RecordLayout.h:240
Expr * getSubExpr()
Definition: Expr.h:3173
void registerGlobalDtorWithAtExit(const VarDecl &D, llvm::FunctionCallee fn, llvm::Constant *addr)
Call atexit() with a function that passes the given argument to the given function.
Definition: CGDeclCXX.cpp:250
Describes a module or submodule.
Definition: Module.h:64
static llvm::FunctionCallee getThrowFn(CodeGenModule &CGM)
IdentifierTable & Idents
Definition: ASTContext.h:569
bool hasPrivateFields() const
Definition: DeclCXX.h:1334
bool hasProtectedFields() const
Definition: DeclCXX.h:1338
static ApplyDebugLocation CreateArtificial(CodeGenFunction &CGF)
Apply TemporaryLocation if it is valid.
Definition: CGDebugInfo.h:730
ArrayRef< ParmVarDecl * > parameters() const
Definition: Decl.h:2289
static bool hasMicrosoftABIRestrictions(const CXXRecordDecl *RD)
ArrayRef< VTableComponent > vtable_components() const
FunctionDecl * getOperatorDelete() const
Definition: ExprCXX.h:2300
Base object ctor.
Definition: ABI.h:26
Address CreateElementBitCast(Address Addr, llvm::Type *Ty, const llvm::Twine &Name="")
Cast the element type of the given address to a different type, preserving information like the align...
Definition: CGBuilder.h:156
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:37
void EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD, llvm::Value *VTable, SourceLocation Loc)
If whole-program virtual table optimization is enabled, emit an assumption that VTable is a member of...
Definition: CGClass.cpp:2625
AccessSpecifier getAccessSpecifier() const
Returns the access specifier for this base specifier.
Definition: DeclCXX.h:272
llvm::CallInst * EmitRuntimeCall(llvm::FunctionCallee callee, const Twine &name="")
const CXXRecordDecl * IntroducingObject
This is the class that introduced the vptr by declaring new virtual methods or virtual bases...
path_iterator path_begin()
Definition: Expr.h:3193
Deleting dtor.
Definition: ABI.h:34
CharUnits getAlignment() const
Return the alignment of this pointer.
Definition: Address.h:66
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:148
static ConstantAddress getInitThreadEpochPtr(CodeGenModule &CGM)
bool isVolatileQualified() const
Determine whether this type is volatile-qualified.
Definition: Type.h:6197
const CGFunctionInfo & arrangeCXXConstructorCall(const CallArgList &Args, const CXXConstructorDecl *D, CXXCtorType CtorKind, unsigned ExtraPrefixArgs, unsigned ExtraSuffixArgs, bool PassProtoArgs=true)
Arrange a call to a C++ method, passing the given arguments.
Definition: CGCall.cpp:389
QualType getExceptionObjectType(QualType T) const
const VPtrInfoVector & getVFPtrOffsets(const CXXRecordDecl *RD)
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Definition: Type.h:6127
CXXRecordDecl * getCanonicalDecl() override
Retrieves the "canonical" declaration of the given declaration.
Definition: DeclCXX.h:730
void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr, QualType DeleteTy, llvm::Value *NumElements=nullptr, CharUnits CookieSize=CharUnits())
Definition: CGExprCXX.cpp:1737
static bool hasDefaultCXXMethodCC(ASTContext &Context, const CXXMethodDecl *MD)
llvm::BasicBlock * createBasicBlock(const Twine &name="", llvm::Function *parent=nullptr, llvm::BasicBlock *before=nullptr)
createBasicBlock - Create an LLVM basic block.
Denotes a cleanup that should run when a scope is exited using normal control flow (falling off the e...
Definition: EHScopeStack.h:84
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:3121
void ForceCleanup(std::initializer_list< llvm::Value **> ValuesToReload={})
Force the emission of cleanups now, instead of waiting until this object is destroyed.
const VBaseOffsetsMapTy & getVBaseOffsetsMap() const
Definition: RecordLayout.h:315
const CGFunctionInfo & arrangeCXXMethodDeclaration(const CXXMethodDecl *MD)
C++ methods have some special rules and also have implicit parameters.
Definition: CGCall.cpp:278
GlobalDecl CurGD
CurGD - The GlobalDecl for the current function being compiled.
bool isInstance() const
Definition: DeclCXX.h:2140
CXXDestructorDecl * getDestructor() const
Returns the destructor decl for this class.
Definition: DeclCXX.cpp:1736
GlobalDecl getWithDtorType(CXXDtorType Type)
Definition: GlobalDecl.h:129
struct clang::ThisAdjustment::VirtualAdjustment::@136 Microsoft
CallingConv getDefaultCallingConvention(bool IsVariadic, bool IsCXXMethod, bool IsBuiltin=false) const
Retrieves the default calling convention for the current target.
bool isNegative() const
isNegative - Test whether the quantity is less than zero.
Definition: CharUnits.h:124
CXXRecordDecl * getMostRecentNonInjectedDecl()
Definition: DeclCXX.h:756
arg_iterator arg_end()
Definition: Expr.h:2718
static ImplicitParamDecl * Create(ASTContext &C, DeclContext *DC, SourceLocation IdLoc, IdentifierInfo *Id, QualType T, ImplicitParamKind ParamKind)
Create implicit parameter.
Definition: Decl.cpp:4557
NodeId Parent
Definition: ASTDiff.cpp:191
bool hasAttr() const
Definition: DeclBase.h:542
CanQualType getReturnType() const
static void emitGlobalDtorWithTLRegDtor(CodeGenFunction &CGF, const VarDecl &VD, llvm::FunctionCallee Dtor, llvm::Constant *Addr)
AutoVarEmission EmitAutoVarAlloca(const VarDecl &var)
EmitAutoVarAlloca - Emit the alloca and debug information for a local variable.
Definition: CGDecl.cpp:1379
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1636
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3704
void EmitAnyExprToMem(const Expr *E, Address Location, Qualifiers Quals, bool IsInitializer)
EmitAnyExprToMem - Emits the code necessary to evaluate an arbitrary expression into the given memory...
Definition: CGExpr.cpp:222
CastKind
CastKind - The kind of operation required for a conversion.
RValue - This trivial value class is used to represent the result of an expression that is evaluated...
Definition: CGValue.h:38
union clang::ReturnAdjustment::VirtualAdjustment Virtual
Module linkage, which indicates that the entity can be referred to from other translation units withi...
Definition: Linkage.h:55
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
Definition: CharUnits.h:178
unsigned Offset
Definition: Format.cpp:1711
ASTRecordLayout - This class contains layout information for one RecordDecl, which is a struct/union/...
Definition: RecordLayout.h:38
llvm::Value * GetVTablePtr(Address This, llvm::Type *VTableTy, const CXXRecordDecl *VTableClass)
GetVTablePtr - Return the Value of the vtable pointer member pointed to by This.
Definition: CGClass.cpp:2575
CXXDtorType
C++ destructor types.
Definition: ABI.h:33
Represent the declaration of a variable (in which case it is an lvalue) a function (in which case it ...
Definition: Decl.h:636
This represents one expression.
Definition: Expr.h:108
bool isPositive() const
isPositive - Test whether the quantity is greater than zero.
Definition: CharUnits.h:121
Enters a new scope for capturing cleanups, all of which will be executed once the scope is exited...
void EmitCallArgs(CallArgList &Args, const T *CallArgTypeInfo, llvm::iterator_range< CallExpr::const_arg_iterator > ArgRange, AbstractCallee AC=AbstractCallee(), unsigned ParamsToSkip=0, EvaluationOrder Order=EvaluationOrder::Default)
EmitCallArgs - Emit call arguments for a function.
const CGFunctionInfo & arrangeNullaryFunction()
A nullary function is a freestanding function of type &#39;void ()&#39;.
Definition: CGCall.cpp:694
static llvm::FunctionCallee getInitThreadAbortFn(CodeGenModule &CGM)
const T * castAs() const
Member-template castAs<specific type>.
Definition: Type.h:6883
static CGCallee forDirect(llvm::Constant *functionPtr, const CGCalleeInfo &abstractInfo=CGCalleeInfo())
Definition: CGCall.h:133
#define V(N, I)
Definition: ASTContext.h:2907
Represents a C++ destructor within a class.
Definition: DeclCXX.h:2830
VarDecl * getExceptionDecl() const
Definition: StmtCXX.h:49
QualType getTagDeclType(const TagDecl *Decl) const
Return the unique reference to the type for the specified TagDecl (struct/union/class/enum) decl...
bool isNullPtrType() const
Definition: Type.h:6635
llvm::PointerType * getType() const
Return the type of the pointer value.
Definition: Address.h:43
CharUnits getTypeAlignInChars(QualType T) const
Return the ABI-specified alignment of a (complete) type T, in characters.
DeclContext * getDeclContext()
Definition: DeclBase.h:438
TLSKind getTLSKind() const
Definition: Decl.cpp:1970
static CharUnits fromQuantity(QuantityType Quantity)
fromQuantity - Construct a CharUnits quantity from a raw integer type.
Definition: CharUnits.h:62
MicrosoftVTableContext & getMicrosoftVTableContext()
static bool classifyReturnType(const CGCXXABI &CXXABI, CGFunctionInfo &FI, const ABIInfo &Info)
Definition: TargetInfo.cpp:158
llvm::LLVMContext & getLLVMContext()
const CXXRecordDecl * getBase() const
getBase - Returns the base class declaration.
Definition: BaseSubobject.h:43
bool isPolymorphic() const
Whether this class is polymorphic (C++ [class.virtual]), which means that the class contains or inher...
Definition: DeclCXX.h:1350
Base object dtor.
Definition: ABI.h:36
QualType getType() const
Definition: Expr.h:137
bool hasNonTrivialDestructor() const
Determine whether this class has a non-trivial destructor (C++ [class.dtor]p3)
Definition: DeclCXX.h:1501
bool hasExtendableVFPtr() const
hasVFPtr - Does this class have a virtual function table pointer that can be extended by a derived cl...
Definition: RecordLayout.h:267
DeclContext * getParent()
getParent - Returns the containing DeclContext.
Definition: DeclBase.h:1772
void GenerateCXXGlobalInitFunc(llvm::Function *Fn, ArrayRef< llvm::Function *> CXXThreadLocals, ConstantAddress Guard=ConstantAddress::invalid())
GenerateCXXGlobalInitFunc - Generates code for initializing global variables.
Definition: CGDeclCXX.cpp:649
llvm::Value * EmitCastToVoidPtr(llvm::Value *value)
Emit a cast to void* in the appropriate address space.
Definition: CGExpr.cpp:49
CharUnits getVBPtrOffset() const
getVBPtrOffset - Get the offset for virtual base table pointer.
Definition: RecordLayout.h:305
const TargetInfo & getTarget() const
void EmitCXXGlobalVarDeclInit(const VarDecl &D, llvm::Constant *DeclPtr, bool PerformInit)
EmitCXXGlobalVarDeclInit - Create the initializer for a C++ variable with global storage.
Definition: CGDeclCXX.cpp:161
QualType getTypeDeclType(const TypeDecl *Decl, const TypeDecl *PrevDecl=nullptr) const
Return the unique reference to the type for the specified type declaration.
Definition: ASTContext.h:1398
ASTContext & getContext() const
bool isNull() const
Return true if this QualType doesn&#39;t point to a type yet.
Definition: Type.h:708
bool nullFieldOffsetIsZero() const
In the Microsoft C++ ABI, use zero for the field offset of a null data member pointer if we can guara...
Definition: DeclCXX.h:1960
The COMDAT used for dtors.
Definition: ABI.h:37
CallingConv
CallingConv - Specifies the calling convention that a function uses.
Definition: Specifiers.h:264
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:40
bool isConstQualified() const
Determine whether this type is const-qualified.
Definition: Type.h:6186
The l-value was considered opaque, so the alignment was determined from a type.
int64_t NonVirtual
The non-virtual adjustment from the derived object to its nearest virtual base.
Definition: ABI.h:44
unsigned getVBTableIndex(const CXXRecordDecl *Derived, const CXXRecordDecl *VBase)
Returns the index of VBase in the vbtable of Derived.
unsigned getEffectiveCallingConvention() const
getEffectiveCallingConvention - Return the actual calling convention to use, which may depend on the ...
Address CreateBitCast(Address Addr, llvm::Type *Ty, const llvm::Twine &Name="")
Definition: CGBuilder.h:141
static llvm::FunctionCallee getInitThreadHeaderFn(CodeGenModule &CGM)
Encodes a location in the source.
IdentifierInfo & get(StringRef Name)
Return the identifier token info for the specified named identifier.
bool isMemberDataPointer() const
Returns true if the member type (i.e.
Definition: Type.h:2803
Address CreateConstInBoundsGEP2_32(Address Addr, unsigned Idx0, unsigned Idx1, const llvm::Twine &Name="")
Definition: CGBuilder.h:258
CastKind getCastKind() const
Definition: Expr.h:3167
RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee, ReturnValueSlot ReturnValue, const CallArgList &Args, llvm::CallBase **callOrInvoke, SourceLocation Loc)
EmitCall - Generate a call of the given function, expecting the given result type, and using the given argument list which specifies both the LLVM arguments and the types they were derived from.
Definition: CGCall.cpp:3776
Represents a new-expression for memory allocation and constructor calls, e.g: "new CXXNewExpr(foo)"...
Definition: ExprCXX.h:2000
Represents a call to a member function that may be written either with member call syntax (e...
Definition: ExprCXX.h:170
ASTContext & getASTContext() const LLVM_READONLY
Definition: DeclBase.cpp:376
static bool IsSizeGreaterThan128(const CXXRecordDecl *RD)
const Decl * getDecl() const
Definition: GlobalDecl.h:76
Represents a single component in a vtable.
Definition: VTableBuilder.h:29
MangleContext - Context for tracking state which persists across multiple calls to the C++ name mangl...
Definition: Mangle.h:43
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2114
const VTableLayout & getVFTableLayout(const CXXRecordDecl *RD, CharUnits VFPtrOffset)
QualType getAllocatedType() const
Definition: ExprCXX.h:2093
llvm::Constant * GetAddrOfRTTIDescriptor(QualType Ty, bool ForEH=false)
Get the address of the RTTI descriptor for the given type.
void createVTableInitializer(ConstantStructBuilder &builder, const VTableLayout &layout, llvm::Constant *rtti)
Add vtable components for the given vtable layout to the given global initializer.
Definition: CGVTables.cpp:710
const CXXRecordDecl * ObjectWithVPtr
This is the most derived class that has this vptr at offset zero.
An aligned address.
Definition: Address.h:24
void StartFunction(GlobalDecl GD, QualType RetTy, llvm::Function *Fn, const CGFunctionInfo &FnInfo, const FunctionArgList &Args, SourceLocation Loc=SourceLocation(), SourceLocation StartLoc=SourceLocation())
Emit code for the start of a function.
DestructionKind isDestructedType() const
Returns a nonzero value if objects of this type require non-trivial work to clean up after...
Definition: Type.h:1163
unsigned getCustomDiagID(Level L, const char(&FormatString)[N])
Return an ID for a diagnostic with the specified format string and level.
Definition: Diagnostic.h:777
All available information about a concrete callee.
Definition: CGCall.h:66
bool canPassInRegisters() const
Determine whether this class can be passed in registers.
Definition: Decl.h:3750
MangleContext & getMangleContext()
Gets the mangle context.
Definition: CGCXXABI.h:96
Complete object dtor.
Definition: ABI.h:35
llvm::Instruction * CurrentFuncletPad
constexpr XRayInstrMask None
Definition: XRayInstr.h:37
CGCXXABI * CreateMicrosoftCXXABI(CodeGenModule &CGM)
Creates a Microsoft-family ABI.
static void mangleVFTableName(MicrosoftMangleContext &MangleContext, const CXXRecordDecl *RD, const VPtrInfo &VFPtr, SmallString< 256 > &Name)
bool isMemberPointerToDerivedMember() const
Definition: APValue.cpp:779
The MS C++ ABI needs a pointer to RTTI data plus some flags to describe the type of a catch handler...
Definition: CGCleanup.h:37
void FinishFunction(SourceLocation EndLoc=SourceLocation())
FinishFunction - Complete IR generation of the current function.
CXXCtorType
C++ constructor types.
Definition: ABI.h:24
SourceLocation getExprLoc() const LLVM_READONLY
getExprLoc - Return the preferred location for the arrow when diagnosing a problem with a generic exp...
Definition: Expr.cpp:215
void addUsedGlobal(llvm::GlobalValue *GV)
Add a global to a list to be added to the llvm.used metadata.
FunctionArgList - Type for representing both the decl and type of parameters to a function...
Definition: CGCall.h:358
llvm::Value * getScalarVal() const
getScalarVal() - Return the Value* of this scalar value.
Definition: CGValue.h:58
CXXRecordDecl * getMostRecentCXXRecordDecl() const
Definition: Type.cpp:4120
bool isVirtuallyDerivedFrom(const CXXRecordDecl *Base) const
Determine whether this class is virtually derived from the class Base.
void ErrorUnsupported(const Stmt *S, const char *Type)
Print out an error that codegen doesn&#39;t support the specified stmt yet.
CGFunctionInfo - Class to encapsulate the information about a function definition.
This class organizes the cross-function state that is used while generating LLVM code.
CharUnits alignmentAtOffset(CharUnits offset) const
Given that this is a non-zero alignment value, what is the alignment at the given offset...
Definition: CharUnits.h:189
llvm::GlobalValue * GetGlobalValue(StringRef Ref)
Dataflow Directional Tag Classes.
void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type, bool ForVirtualBase, bool Delegating, Address This)
Definition: CGClass.cpp:2402
External linkage within a unique namespace.
Definition: Linkage.h:40
static bool isDeletingDtor(GlobalDecl GD)
uint64_t Index
Method&#39;s index in the vftable.
Represents a delete expression for memory deallocation and destructor calls, e.g. ...
Definition: ExprCXX.h:2260
const VPtrInfoVector & enumerateVBTables(const CXXRecordDecl *RD)
llvm::LoadInst * CreateAlignedLoad(llvm::Value *Addr, CharUnits Align, const llvm::Twine &Name="")
Definition: CGBuilder.h:90
llvm::Constant * getPointer() const
Definition: Address.h:83
std::unique_ptr< DiagnosticConsumer > create(StringRef OutputFile, DiagnosticOptions *Diags, bool MergeChildRecords=false)
Returns a DiagnosticConsumer that serializes diagnostics to a bitcode file.
llvm::LoadInst * CreateLoad(Address Addr, const llvm::Twine &Name="")
Definition: CGBuilder.h:69
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2237
A pointer to member type per C++ 8.3.3 - Pointers to members.
Definition: Type.h:2773
CharUnits NonVirtualOffset
IntroducingObject is at this offset from its containing complete object or virtual base...
llvm::StoreInst * CreateStore(llvm::Value *Val, Address Addr, bool IsVolatile=false)
Definition: CGBuilder.h:107
llvm::Module & getModule() const
void maybeSetTrivialComdat(const Decl &D, llvm::GlobalObject &GO)
CharUnits getVBaseAlignment(CharUnits DerivedAlign, const CXXRecordDecl *Derived, const CXXRecordDecl *VBase)
Returns the assumed alignment of a virtual base of a class.
Definition: CGClass.cpp:55
ArrayRef< const CXXRecordDecl * > getMemberPointerPath() const
Definition: APValue.cpp:786
llvm::Function * createAtExitStub(const VarDecl &VD, llvm::FunctionCallee Dtor, llvm::Constant *Addr)
Create a stub function, suitable for being passed to atexit, which passes the given address to the gi...
Definition: CGDeclCXX.cpp:217
union clang::ThisAdjustment::VirtualAdjustment Virtual
bool hasNonTrivialCopyAssignment() const
Determine whether this class has a non-trivial copy assignment operator (C++ [class.copy]p11, C++11 [class.copy]p25)
Definition: DeclCXX.h:1469
path_iterator path_end()
Definition: Expr.h:3194
void EmitAutoVarCleanups(const AutoVarEmission &emission)
Definition: CGDecl.cpp:1978
void EmitNoreturnRuntimeCallOrInvoke(llvm::FunctionCallee callee, ArrayRef< llvm::Value *> args)
Emits a call or invoke to the given noreturn runtime function.
Definition: CGCall.cpp:3705
void AppendLinkerOptions(StringRef Opts)
Appends Opts to the "llvm.linker.options" metadata value.
static llvm::GlobalVariable * getTypeInfoVTable(CodeGenModule &CGM)
StructBuilder beginStruct(llvm::StructType *structTy=nullptr)
const CXXRecordDecl * getVBaseWithVPtr() const
The vptr is stored inside the non-virtual component of this virtual base.
arg_iterator arg_begin()
Definition: Expr.h:2715
Implements C++ ABI-specific code generation functions.
Definition: CGCXXABI.h:43
This class organizes the cross-module state that is used while lowering AST types to LLVM types...
Definition: CodeGenTypes.h:59
bool isStaticLocal() const
Returns true if a variable with function scope is a static local variable.
Definition: Decl.h:1059
llvm::Constant * GetAddrOfFunction(GlobalDecl GD, llvm::Type *Ty=nullptr, bool ForVTable=false, bool DontDefer=false, ForDefinition_t IsForDefinition=NotForDefinition)
Return the address of the given function.
StringRef getMangledName(GlobalDecl GD)
Internal linkage, which indicates that the entity can be referred to from within the translation unit...
Definition: Linkage.h:31
llvm::FunctionCallee CreateRuntimeFunction(llvm::FunctionType *Ty, StringRef Name, llvm::AttributeList ExtraAttrs=llvm::AttributeList(), bool Local=false)
Create or return a runtime function declaration with the specified type and name. ...
void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false)
EmitBlock - Emit the given block.
Definition: CGStmt.cpp:450
APValue - This class implements a discriminated union of [uninitialized] [APSInt] [APFloat]...
Definition: APValue.h:76
Represents a base class of a C++ class.
Definition: DeclCXX.h:192
bool isObjectType() const
Determine whether this type is an object type.
Definition: Type.h:1879
uint64_t getTypeSize(QualType T) const
Return the size of the specified (complete) type T, in bits.
Definition: ASTContext.h:2079
static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT, CGCXXABI &CXXABI)
Definition: TargetInfo.cpp:139
const Decl * CurFuncDecl
CurFuncDecl - Holds the Decl for the current outermost non-closure context.
uint64_t getFieldOffset(const ValueDecl *FD) const
Get the offset of a FieldDecl or IndirectFieldDecl, in bits.
CharUnits toCharUnitsFromBits(int64_t BitSize) const
Convert a size in bits to a size in characters.
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate.h) and friends (in DeclFriend.h).
static bool isInstanceMethod(const Decl *D)
QualType getUnqualifiedType() const
Retrieve the unqualified variant of the given type, removing as little sugar as possible.
Definition: Type.h:6207
Address CreateConstByteGEP(Address Addr, CharUnits Offset, const llvm::Twine &Name="")
Definition: CGBuilder.h:250
bool hasUnaligned() const
Definition: Type.h:293
Represents a C++ struct/union/class.
Definition: DeclCXX.h:300
bool isMemberFunctionPointer() const
Returns true if the member type (i.e.
Definition: Type.h:2797
llvm::Function * CreateGlobalInitOrDestructFunction(llvm::FunctionType *ty, const Twine &name, const CGFunctionInfo &FI, SourceLocation Loc=SourceLocation(), bool TLS=false)
Definition: CGDeclCXX.cpp:323
CXXCatchStmt - This represents a C++ catch block.
Definition: StmtCXX.h:28
llvm::Type * ConvertType(QualType T)
Qualifiers getQualifiers() const
Retrieve the set of qualifiers applied to this type.
Definition: Type.h:6154
A specialization of Address that requires the address to be an LLVM Constant.
Definition: Address.h:74
int32_t VtordispOffset
The offset of the vtordisp (in bytes), relative to the ECX.
Definition: ABI.h:124
Address ReturnValue
ReturnValue - The temporary alloca to hold the return value.
No linkage according to the standard, but is visible from other translation units because of types de...
Definition: Linkage.h:44
QualType getPointerType(QualType T) const
Return the uniqued reference to the type for a pointer to the specified type.
static CGCallee forVirtual(const CallExpr *CE, GlobalDecl MD, Address Addr, llvm::FunctionType *FTy)
Definition: CGCall.h:144
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
Definition: Stmt.cpp:251
llvm::DenseMap< const CXXRecordDecl *, VBaseInfo > VBaseOffsetsMapTy
Definition: RecordLayout.h:59
bool isGlobalDelete() const
Definition: ExprCXX.h:2286
Copying closure variant of a ctor.
Definition: ABI.h:28
CharUnits computeNonVirtualBaseClassOffset(const CXXRecordDecl *DerivedClass, CastExpr::path_const_iterator Start, CastExpr::path_const_iterator End)
Definition: CGClass.cpp:149
CharUnits FullOffsetInMDC
Static offset from the top of the most derived class to this vfptr, including any virtual base offset...
const CGFunctionInfo & arrangeMSCtorClosure(const CXXConstructorDecl *CD, CXXCtorType CT)
Definition: CGCall.cpp:539
__DEVICE__ int max(int __a, int __b)
CanQualType IntTy
Definition: ASTContext.h:1023
Struct with all information about dynamic [sub]class needed to set vptr.
void initialize(TemplateInstantiationCallbackPtrs &Callbacks, const Sema &TheSema)
llvm::Function * codegenCXXStructor(GlobalDecl GD)
Definition: CGCXX.cpp:206
MethodVFTableLocation getMethodVFTableLocation(GlobalDecl GD)
static RValue get(llvm::Value *V)
Definition: CGValue.h:85
GVALinkage
A more specific kind of linkage than enum Linkage.
Definition: Linkage.h:73
Holds information about the inheritance path to a virtual base or function table pointer.
bool isPointerType() const
Definition: Type.h:6351
CharUnits getTypeSizeInChars(QualType T) const
Return the size of the specified (complete) type T, in characters.
static ApplyDebugLocation CreateEmpty(CodeGenFunction &CGF)
Set the IRBuilder to not attach debug locations.
Definition: CGDebugInfo.h:747
llvm::StoreInst * CreateAlignedStore(llvm::Value *Val, llvm::Value *Addr, CharUnits Align, bool IsVolatile=false)
Definition: CGBuilder.h:114
QualType getType() const
Definition: Decl.h:647
uint32_t VBIndex
Index of the virtual base in the vbtable.
Definition: ABI.h:63
LValue - This represents an lvalue references.
Definition: CGValue.h:166
Information for lazily generating a cleanup.
Definition: EHScopeStack.h:146
This represents a decl that may have a name.
Definition: Decl.h:248
void EmitMustTailThunk(GlobalDecl GD, llvm::Value *AdjustedThisPtr, llvm::FunctionCallee Callee)
Emit a musttail call for a thunk with a potentially adjusted this pointer.
Definition: CGVTables.cpp:376
BasePath PathToIntroducingObject
This holds the base classes path from the complete type to the first base with the given vfptr offset...
const CXXConstructorDecl * getCopyConstructorForExceptionObject(CXXRecordDecl *RD)
bool CurFuncIsThunk
In C++, whether we are code generating a thunk.
Notes how many arguments were added to the beginning (Prefix) and ending (Suffix) of an arg list...
Definition: CGCXXABI.h:295
RecordArgABI
Specify how one should pass an argument of a record type.
Definition: CGCXXABI.h:125
llvm::CallInst * EmitNounwindRuntimeCall(llvm::FunctionCallee callee, const Twine &name="")
llvm::CallBase * EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee, ArrayRef< llvm::Value *> args, const Twine &name="")
Emits a call or invoke instruction to the given runtime function.
Definition: CGCall.cpp:3736
unsigned getNumParams() const
Return the number of parameters this function must have based on its FunctionType.
Definition: Decl.cpp:3138
ctor_range ctors() const
Definition: DeclCXX.h:887
CallArgList - Type for representing both the value and type of arguments in a call.
Definition: CGCall.h:262
int32_t VBPtrOffset
The offset of the vbptr of the derived class (in bytes), relative to the ECX after vtordisp adjustmen...
Definition: ABI.h:128
void PopCleanupBlock(bool FallThroughIsBranchThrough=false)
PopCleanupBlock - Will pop the cleanup entry on the stack and process all branch fixups.
Definition: CGCleanup.cpp:644
static void serializeClassHierarchy(SmallVectorImpl< MSRTTIClass > &Classes, const CXXRecordDecl *RD)
Recursively serializes a class hierarchy in pre-order depth first order.
base_class_range vbases()
Definition: DeclCXX.h:842
static ABIArgInfo getIndirect(CharUnits Alignment, bool ByVal=true, bool Realign=false, llvm::Type *Padding=nullptr)
llvm::Value * EmitVTableTypeCheckedLoad(const CXXRecordDecl *RD, llvm::Value *VTable, uint64_t VTableByteOffset)
Emit a type checked load from the given vtable.
Definition: CGClass.cpp:2787
SourceLocation getLocation() const
Definition: DeclBase.h:429
QualType getPointeeType() const
Definition: Type.h:2793
bool isExternallyVisible() const
Definition: Decl.h:379
static OMPLinearClause * Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc, OpenMPLinearClauseKind Modifier, SourceLocation ModifierLoc, SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef< Expr *> VL, ArrayRef< Expr *> PL, ArrayRef< Expr *> IL, Expr *Step, Expr *CalcStep, Stmt *PreInit, Expr *PostUpdate)
Creates clause with a list of variables VL and a linear step Step.
CanQualType getSizeType() const
Return the unique type for "size_t" (C99 7.17), defined in <stddef.h>.
llvm::FunctionType * GetFunctionType(const CGFunctionInfo &Info)
GetFunctionType - Get the LLVM function type for.
Definition: CGCall.cpp:1541
bool isNoDestroy(const ASTContext &) const
Do we need to emit an exit-time destructor for this variable?
Definition: Decl.cpp:2562