1//===----- CGCXXABI.h - Interface to C++ ABIs -------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This provides an abstract class for C++ code generation. Concrete subclasses
11// of this implement code generation for specific C++ ABIs.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_LIB_CODEGEN_CGCXXABI_H
16#define LLVM_CLANG_LIB_CODEGEN_CGCXXABI_H
17
18#include "CodeGenFunction.h"
19#include "clang/Basic/LLVM.h"
20
21namespace llvm {
22class Constant;
23class Type;
24class Value;
25class CallInst;
26}
27
28namespace clang {
29class CastExpr;
30class CXXConstructorDecl;
31class CXXDestructorDecl;
32class CXXMethodDecl;
33class CXXRecordDecl;
34class FieldDecl;
35class MangleContext;
36
37namespace CodeGen {
38class CodeGenFunction;
39class CodeGenModule;
40struct CatchTypeInfo;
41
42/// \brief Implements C++ ABI-specific code generation functions.
43class CGCXXABI {
44protected:
45  CodeGenModule &CGM;
46  std::unique_ptr<MangleContext> MangleCtx;
47
48  CGCXXABI(CodeGenModule &CGM)
49    : CGM(CGM), MangleCtx(CGM.getContext().createMangleContext()) {}
50
51protected:
52  ImplicitParamDecl *getThisDecl(CodeGenFunction &CGF) {
53    return CGF.CXXABIThisDecl;
54  }
55  llvm::Value *getThisValue(CodeGenFunction &CGF) {
56    return CGF.CXXABIThisValue;
57  }
58  Address getThisAddress(CodeGenFunction &CGF) {
59    return Address(CGF.CXXABIThisValue, CGF.CXXABIThisAlignment);
60  }
61
62  /// Issue a diagnostic about unsupported features in the ABI.
63  void ErrorUnsupportedABI(CodeGenFunction &CGF, StringRef S);
64
65  /// Get a null value for unsupported member pointers.
66  llvm::Constant *GetBogusMemberPointer(QualType T);
67
68  ImplicitParamDecl *&getStructorImplicitParamDecl(CodeGenFunction &CGF) {
69    return CGF.CXXStructorImplicitParamDecl;
70  }
71  llvm::Value *&getStructorImplicitParamValue(CodeGenFunction &CGF) {
72    return CGF.CXXStructorImplicitParamValue;
73  }
74
75  /// Perform prolog initialization of the parameter variable suitable
76  /// for 'this' emitted by buildThisParam.
77  void EmitThisParam(CodeGenFunction &CGF);
78
79  ASTContext &getContext() const { return CGM.getContext(); }
80
81  virtual bool requiresArrayCookie(const CXXDeleteExpr *E, QualType eltType);
82  virtual bool requiresArrayCookie(const CXXNewExpr *E);
83
84  /// Determine whether there's something special about the rules of
85  /// the ABI tell us that 'this' is a complete object within the
86  /// given function.  Obvious common logic like being defined on a
87  /// final class will have been taken care of by the caller.
88  virtual bool isThisCompleteObject(GlobalDecl GD) const = 0;
89
90public:
91
92  virtual ~CGCXXABI();
93
94  /// Gets the mangle context.
95  MangleContext &getMangleContext() {
96    return *MangleCtx;
97  }
98
99  /// Returns true if the given constructor or destructor is one of the
100  /// kinds that the ABI says returns 'this' (only applies when called
101  /// non-virtually for destructors).
102  ///
103  /// There currently is no way to indicate if a destructor returns 'this'
104  /// when called virtually, and code generation does not support the case.
105  virtual bool HasThisReturn(GlobalDecl GD) const { return false; }
106
107  virtual bool hasMostDerivedReturn(GlobalDecl GD) const { return false; }
108
109  /// Returns true if the target allows calling a function through a pointer
110  /// with a different signature than the actual function (or equivalently,
111  /// bitcasting a function or function pointer to a different function type).
112  /// In principle in the most general case this could depend on the target, the
113  /// calling convention, and the actual types of the arguments and return
114  /// value. Here it just means whether the signature mismatch could *ever* be
115  /// allowed; in other words, does the target do strict checking of signatures
116  /// for all calls.
117  virtual bool canCallMismatchedFunctionType() const { return true; }
118
119  /// If the C++ ABI requires the given type be returned in a particular way,
120  /// this method sets RetAI and returns true.
121  virtual bool classifyReturnType(CGFunctionInfo &FI) const = 0;
122
123  /// Specify how one should pass an argument of a record type.
124  enum RecordArgABI {
125    /// Pass it using the normal C aggregate rules for the ABI, potentially
126    /// introducing extra copies and passing some or all of it in registers.
127    RAA_Default = 0,
128
129    /// Pass it on the stack using its defined layout.  The argument must be
130    /// evaluated directly into the correct stack position in the arguments area,
131    /// and the call machinery must not move it or introduce extra copies.
132    RAA_DirectInMemory,
133
134    /// Pass it as a pointer to temporary memory.
135    RAA_Indirect
136  };
137
138  /// Returns true if C++ allows us to copy the memory of an object of type RD
139  /// when it is passed as an argument.
140  bool canCopyArgument(const CXXRecordDecl *RD) const;
141
142  /// Returns how an argument of the given record type should be passed.
143  virtual RecordArgABI getRecordArgABI(const CXXRecordDecl *RD) const = 0;
144
145  /// Returns true if the implicit 'sret' parameter comes after the implicit
146  /// 'this' parameter of C++ instance methods.
147  virtual bool isSRetParameterAfterThis() const { return false; }
148
149  /// Find the LLVM type used to represent the given member pointer
150  /// type.
151  virtual llvm::Type *
152  ConvertMemberPointerType(const MemberPointerType *MPT);
153
154  /// Load a member function from an object and a member function
155  /// pointer.  Apply the this-adjustment and set 'This' to the
156  /// adjusted value.
157  virtual llvm::Value *EmitLoadOfMemberFunctionPointer(
158      CodeGenFunction &CGF, const Expr *E, Address This,
159      llvm::Value *&ThisPtrForCall, llvm::Value *MemPtr,
160      const MemberPointerType *MPT);
161
162  /// Calculate an l-value from an object and a data member pointer.
163  virtual llvm::Value *
164  EmitMemberDataPointerAddress(CodeGenFunction &CGF, const Expr *E,
165                               Address Base, llvm::Value *MemPtr,
166                               const MemberPointerType *MPT);
167
168  /// Perform a derived-to-base, base-to-derived, or bitcast member
169  /// pointer conversion.
170  virtual llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
171                                                   const CastExpr *E,
172                                                   llvm::Value *Src);
173
174  /// Perform a derived-to-base, base-to-derived, or bitcast member
175  /// pointer conversion on a constant value.
176  virtual llvm::Constant *EmitMemberPointerConversion(const CastExpr *E,
177                                                      llvm::Constant *Src);
178
179  /// Return true if the given member pointer can be zero-initialized
180  /// (in the C++ sense) with an LLVM zeroinitializer.
181  virtual bool isZeroInitializable(const MemberPointerType *MPT);
182
183  /// Return whether or not a member pointers type is convertible to an IR type.
184  virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const {
185    return true;
186  }
187
188  /// Create a null member pointer of the given type.
189  virtual llvm::Constant *EmitNullMemberPointer(const MemberPointerType *MPT);
190
191  /// Create a member pointer for the given method.
192  virtual llvm::Constant *EmitMemberFunctionPointer(const CXXMethodDecl *MD);
193
194  /// Create a member pointer for the given field.
195  virtual llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
196                                                CharUnits offset);
197
198  /// Create a member pointer for the given member pointer constant.
199  virtual llvm::Constant *EmitMemberPointer(const APValue &MP, QualType MPT);
200
201  /// Emit a comparison between two member pointers.  Returns an i1.
202  virtual llvm::Value *
203  EmitMemberPointerComparison(CodeGenFunction &CGF,
204                              llvm::Value *L,
205                              llvm::Value *R,
206                              const MemberPointerType *MPT,
207                              bool Inequality);
208
209  /// Determine if a member pointer is non-null.  Returns an i1.
210  virtual llvm::Value *
211  EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
212                             llvm::Value *MemPtr,
213                             const MemberPointerType *MPT);
214
215protected:
216  /// A utility method for computing the offset required for the given
217  /// base-to-derived or derived-to-base member-pointer conversion.
218  /// Does not handle virtual conversions (in case we ever fully
219  /// support an ABI that allows this).  Returns null if no adjustment
220  /// is required.
221  llvm::Constant *getMemberPointerAdjustment(const CastExpr *E);
222
223  /// \brief Computes the non-virtual adjustment needed for a member pointer
224  /// conversion along an inheritance path stored in an APValue.  Unlike
225  /// getMemberPointerAdjustment(), the adjustment can be negative if the path
226  /// is from a derived type to a base type.
227  CharUnits getMemberPointerPathAdjustment(const APValue &MP);
228
229public:
230  virtual void emitVirtualObjectDelete(CodeGenFunction &CGF,
231                                       const CXXDeleteExpr *DE,
232                                       Address Ptr, QualType ElementType,
233                                       const CXXDestructorDecl *Dtor) = 0;
234  virtual void emitRethrow(CodeGenFunction &CGF, bool isNoReturn) = 0;
235  virtual void emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) = 0;
236  virtual llvm::GlobalVariable *getThrowInfo(QualType T) { return nullptr; }
237
238  /// \brief Determine whether it's possible to emit a vtable for \p RD, even
239  /// though we do not know that the vtable has been marked as used by semantic
240  /// analysis.
241  virtual bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const = 0;
242
243  virtual void emitBeginCatch(CodeGenFunction &CGF, const CXXCatchStmt *C) = 0;
244
245  virtual llvm::CallInst *
246  emitTerminateForUnexpectedException(CodeGenFunction &CGF,
247                                      llvm::Value *Exn);
248
249  virtual llvm::Constant *getAddrOfRTTIDescriptor(QualType Ty) = 0;
250  virtual CatchTypeInfo
251  getAddrOfCXXCatchHandlerType(QualType Ty, QualType CatchHandlerType) = 0;
252  virtual CatchTypeInfo getCatchAllTypeInfo();
253
254  virtual bool shouldTypeidBeNullChecked(bool IsDeref,
255                                         QualType SrcRecordTy) = 0;
256  virtual void EmitBadTypeidCall(CodeGenFunction &CGF) = 0;
257  virtual llvm::Value *EmitTypeid(CodeGenFunction &CGF, QualType SrcRecordTy,
258                                  Address ThisPtr,
259                                  llvm::Type *StdTypeInfoPtrTy) = 0;
260
261  virtual bool shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
262                                                  QualType SrcRecordTy) = 0;
263
264  virtual llvm::Value *
265  EmitDynamicCastCall(CodeGenFunction &CGF, Address Value,
266                      QualType SrcRecordTy, QualType DestTy,
267                      QualType DestRecordTy, llvm::BasicBlock *CastEnd) = 0;
268
269  virtual llvm::Value *EmitDynamicCastToVoid(CodeGenFunction &CGF,
270                                             Address Value,
271                                             QualType SrcRecordTy,
272                                             QualType DestTy) = 0;
273
274  virtual bool EmitBadCastCall(CodeGenFunction &CGF) = 0;
275
276  virtual llvm::Value *GetVirtualBaseClassOffset(CodeGenFunction &CGF,
277                                                 Address This,
278                                                 const CXXRecordDecl *ClassDecl,
279                                        const CXXRecordDecl *BaseClassDecl) = 0;
280
281  virtual llvm::BasicBlock *EmitCtorCompleteObjectHandler(CodeGenFunction &CGF,
282                                                          const CXXRecordDecl *RD);
283
284  /// Emit the code to initialize hidden members required
285  /// to handle virtual inheritance, if needed by the ABI.
286  virtual void
287  initializeHiddenVirtualInheritanceMembers(CodeGenFunction &CGF,
288                                            const CXXRecordDecl *RD) {}
289
290  /// Emit constructor variants required by this ABI.
291  virtual void EmitCXXConstructors(const CXXConstructorDecl *D) = 0;
292
293  /// Build the signature of the given constructor or destructor variant by
294  /// adding any required parameters.  For convenience, ArgTys has been
295  /// initialized with the type of 'this'.
296  virtual void buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
297                                      SmallVectorImpl<CanQualType> &ArgTys) = 0;
298
299  /// Returns true if the given destructor type should be emitted as a linkonce
300  /// delegating thunk, regardless of whether the dtor is defined in this TU or
301  /// not.
302  virtual bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
303                                      CXXDtorType DT) const = 0;
304
305  /// Emit destructor variants required by this ABI.
306  virtual void EmitCXXDestructors(const CXXDestructorDecl *D) = 0;
307
308  /// Get the type of the implicit "this" parameter used by a method. May return
309  /// zero if no specific type is applicable, e.g. if the ABI expects the "this"
310  /// parameter to point to some artificial offset in a complete object due to
311  /// vbases being reordered.
312  virtual const CXXRecordDecl *
313  getThisArgumentTypeForMethod(const CXXMethodDecl *MD) {
314    return MD->getParent();
315  }
316
317  /// Perform ABI-specific "this" argument adjustment required prior to
318  /// a call of a virtual function.
319  /// The "VirtualCall" argument is true iff the call itself is virtual.
320  virtual Address
321  adjustThisArgumentForVirtualFunctionCall(CodeGenFunction &CGF, GlobalDecl GD,
322                                           Address This, bool VirtualCall) {
323    return This;
324  }
325
326  /// Build a parameter variable suitable for 'this'.
327  void buildThisParam(CodeGenFunction &CGF, FunctionArgList &Params);
328
329  /// Insert any ABI-specific implicit parameters into the parameter list for a
330  /// function.  This generally involves extra data for constructors and
331  /// destructors.
332  ///
333  /// ABIs may also choose to override the return type, which has been
334  /// initialized with the type of 'this' if HasThisReturn(CGF.CurGD) is true or
335  /// the formal return type of the function otherwise.
336  virtual void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
337                                         FunctionArgList &Params) = 0;
338
339  /// Get the ABI-specific "this" parameter adjustment to apply in the prologue
340  /// of a virtual function.
341  virtual CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD) {
342    return CharUnits::Zero();
343  }
344
345  /// Perform ABI-specific "this" parameter adjustment in a virtual function
346  /// prologue.
347  virtual llvm::Value *adjustThisParameterInVirtualFunctionPrologue(
348      CodeGenFunction &CGF, GlobalDecl GD, llvm::Value *This) {
349    return This;
350  }
351
352  /// Emit the ABI-specific prolog for the function.
353  virtual void EmitInstanceFunctionProlog(CodeGenFunction &CGF) = 0;
354
355  /// Add any ABI-specific implicit arguments needed to call a constructor.
356  ///
357  /// \return The number of args added to the call, which is typically zero or
358  /// one.
359  virtual unsigned
360  addImplicitConstructorArgs(CodeGenFunction &CGF, const CXXConstructorDecl *D,
361                             CXXCtorType Type, bool ForVirtualBase,
362                             bool Delegating, CallArgList &Args) = 0;
363
364  /// Emit the destructor call.
365  virtual void EmitDestructorCall(CodeGenFunction &CGF,
366                                  const CXXDestructorDecl *DD, CXXDtorType Type,
367                                  bool ForVirtualBase, bool Delegating,
368                                  Address This) = 0;
369
370  /// Emits the VTable definitions required for the given record type.
371  virtual void emitVTableDefinitions(CodeGenVTables &CGVT,
372                                     const CXXRecordDecl *RD) = 0;
373
374  /// Checks if ABI requires extra virtual offset for vtable field.
375  virtual bool
376  isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
377                                      CodeGenFunction::VPtr Vptr) = 0;
378
379  /// Checks if ABI requires to initilize vptrs for given dynamic class.
380  virtual bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass) = 0;
381
382  /// Get the address point of the vtable for the given base subobject.
383  virtual llvm::Constant *
384  getVTableAddressPoint(BaseSubobject Base,
385                        const CXXRecordDecl *VTableClass) = 0;
386
387  /// Get the address point of the vtable for the given base subobject while
388  /// building a constructor or a destructor.
389  virtual llvm::Value *
390  getVTableAddressPointInStructor(CodeGenFunction &CGF, const CXXRecordDecl *RD,
391                                  BaseSubobject Base,
392                                  const CXXRecordDecl *NearestVBase) = 0;
393
394  /// Get the address point of the vtable for the given base subobject while
395  /// building a constexpr.
396  virtual llvm::Constant *
397  getVTableAddressPointForConstExpr(BaseSubobject Base,
398                                    const CXXRecordDecl *VTableClass) = 0;
399
400  /// Get the address of the vtable for the given record decl which should be
401  /// used for the vptr at the given offset in RD.
402  virtual llvm::GlobalVariable *getAddrOfVTable(const CXXRecordDecl *RD,
403                                                CharUnits VPtrOffset) = 0;
404
405  /// Build a virtual function pointer in the ABI-specific way.
406  virtual llvm::Value *getVirtualFunctionPointer(CodeGenFunction &CGF,
407                                                 GlobalDecl GD,
408                                                 Address This,
409                                                 llvm::Type *Ty,
410                                                 SourceLocation Loc) = 0;
411
412  /// Emit the ABI-specific virtual destructor call.
413  virtual llvm::Value *
414  EmitVirtualDestructorCall(CodeGenFunction &CGF, const CXXDestructorDecl *Dtor,
415                            CXXDtorType DtorType, Address This,
416                            const CXXMemberCallExpr *CE) = 0;
417
418  virtual void adjustCallArgsForDestructorThunk(CodeGenFunction &CGF,
419                                                GlobalDecl GD,
420                                                CallArgList &CallArgs) {}
421
422  /// Emit any tables needed to implement virtual inheritance.  For Itanium,
423  /// this emits virtual table tables.  For the MSVC++ ABI, this emits virtual
424  /// base tables.
425  virtual void emitVirtualInheritanceTables(const CXXRecordDecl *RD) = 0;
426
427  virtual void setThunkLinkage(llvm::Function *Thunk, bool ForVTable,
428                               GlobalDecl GD, bool ReturnAdjustment) = 0;
429
430  virtual llvm::Value *performThisAdjustment(CodeGenFunction &CGF,
431                                             Address This,
432                                             const ThisAdjustment &TA) = 0;
433
434  virtual llvm::Value *performReturnAdjustment(CodeGenFunction &CGF,
435                                               Address Ret,
436                                               const ReturnAdjustment &RA) = 0;
437
438  virtual void EmitReturnFromThunk(CodeGenFunction &CGF,
439                                   RValue RV, QualType ResultType);
440
441  virtual size_t getSrcArgforCopyCtor(const CXXConstructorDecl *,
442                                      FunctionArgList &Args) const = 0;
443
444  /// Gets the offsets of all the virtual base pointers in a given class.
445  virtual std::vector<CharUnits> getVBPtrOffsets(const CXXRecordDecl *RD);
446
447  /// Gets the pure virtual member call function.
448  virtual StringRef GetPureVirtualCallName() = 0;
449
450  /// Gets the deleted virtual member call name.
451  virtual StringRef GetDeletedVirtualCallName() = 0;
452
453  /**************************** Array cookies ******************************/
454
455  /// Returns the extra size required in order to store the array
456  /// cookie for the given new-expression.  May return 0 to indicate that no
457  /// array cookie is required.
458  ///
459  /// Several cases are filtered out before this method is called:
460  ///   - non-array allocations never need a cookie
461  ///   - calls to \::operator new(size_t, void*) never need a cookie
462  ///
463  /// \param expr - the new-expression being allocated.
464  virtual CharUnits GetArrayCookieSize(const CXXNewExpr *expr);
465
466  /// Initialize the array cookie for the given allocation.
467  ///
468  /// \param NewPtr - a char* which is the presumed-non-null
469  ///   return value of the allocation function
470  /// \param NumElements - the computed number of elements,
471  ///   potentially collapsed from the multidimensional array case;
472  ///   always a size_t
473  /// \param ElementType - the base element allocated type,
474  ///   i.e. the allocated type after stripping all array types
475  virtual Address InitializeArrayCookie(CodeGenFunction &CGF,
476                                        Address NewPtr,
477                                        llvm::Value *NumElements,
478                                        const CXXNewExpr *expr,
479                                        QualType ElementType);
480
481  /// Reads the array cookie associated with the given pointer,
482  /// if it has one.
483  ///
484  /// \param Ptr - a pointer to the first element in the array
485  /// \param ElementType - the base element type of elements of the array
486  /// \param NumElements - an out parameter which will be initialized
487  ///   with the number of elements allocated, or zero if there is no
488  ///   cookie
489  /// \param AllocPtr - an out parameter which will be initialized
490  ///   with a char* pointing to the address returned by the allocation
491  ///   function
492  /// \param CookieSize - an out parameter which will be initialized
493  ///   with the size of the cookie, or zero if there is no cookie
494  virtual void ReadArrayCookie(CodeGenFunction &CGF, Address Ptr,
495                               const CXXDeleteExpr *expr,
496                               QualType ElementType, llvm::Value *&NumElements,
497                               llvm::Value *&AllocPtr, CharUnits &CookieSize);
498
499  /// Return whether the given global decl needs a VTT parameter.
500  virtual bool NeedsVTTParameter(GlobalDecl GD);
501
502protected:
503  /// Returns the extra size required in order to store the array
504  /// cookie for the given type.  Assumes that an array cookie is
505  /// required.
506  virtual CharUnits getArrayCookieSizeImpl(QualType elementType);
507
508  /// Reads the array cookie for an allocation which is known to have one.
509  /// This is called by the standard implementation of ReadArrayCookie.
510  ///
511  /// \param ptr - a pointer to the allocation made for an array, as a char*
512  /// \param cookieSize - the computed cookie size of an array
513  ///
514  /// Other parameters are as above.
515  ///
516  /// \return a size_t
517  virtual llvm::Value *readArrayCookieImpl(CodeGenFunction &IGF, Address ptr,
518                                           CharUnits cookieSize);
519
520public:
521
522  /*************************** Static local guards ****************************/
523
524  /// Emits the guarded initializer and destructor setup for the given
525  /// variable, given that it couldn't be emitted as a constant.
526  /// If \p PerformInit is false, the initialization has been folded to a
527  /// constant and should not be performed.
528  ///
529  /// The variable may be:
530  ///   - a static local variable
531  ///   - a static data member of a class template instantiation
532  virtual void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
533                               llvm::GlobalVariable *DeclPtr,
534                               bool PerformInit) = 0;
535
536  /// Emit code to force the execution of a destructor during global
537  /// teardown.  The default implementation of this uses atexit.
538  ///
539  /// \param Dtor - a function taking a single pointer argument
540  /// \param Addr - a pointer to pass to the destructor function.
541  virtual void registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
542                                  llvm::Constant *Dtor,
543                                  llvm::Constant *Addr) = 0;
544
545  /*************************** thread_local initialization ********************/
546
547  /// Emits ABI-required functions necessary to initialize thread_local
548  /// variables in this translation unit.
549  ///
550  /// \param CXXThreadLocals - The thread_local declarations in this translation
551  ///        unit.
552  /// \param CXXThreadLocalInits - If this translation unit contains any
553  ///        non-constant initialization or non-trivial destruction for
554  ///        thread_local variables, a list of functions to perform the
555  ///        initialization.
556  virtual void EmitThreadLocalInitFuncs(
557      CodeGenModule &CGM, ArrayRef<const VarDecl *> CXXThreadLocals,
558      ArrayRef<llvm::Function *> CXXThreadLocalInits,
559      ArrayRef<const VarDecl *> CXXThreadLocalInitVars) = 0;
560
561  // Determine if references to thread_local global variables can be made
562  // directly or require access through a thread wrapper function.
563  virtual bool usesThreadWrapperFunction() const = 0;
564
565  /// Emit a reference to a non-local thread_local variable (including
566  /// triggering the initialization of all thread_local variables in its
567  /// translation unit).
568  virtual LValue EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF,
569                                              const VarDecl *VD,
570                                              QualType LValType) = 0;
571
572  /// Emit a single constructor/destructor with the given type from a C++
573  /// constructor Decl.
574  virtual void emitCXXStructor(const CXXMethodDecl *MD, StructorType Type) = 0;
575};
576
577// Create an instance of a C++ ABI class:
578
579/// Creates an Itanium-family ABI.
580CGCXXABI *CreateItaniumCXXABI(CodeGenModule &CGM);
581
582/// Creates a Microsoft-family ABI.
583CGCXXABI *CreateMicrosoftCXXABI(CodeGenModule &CGM);
584
585}
586}
587
588#endif
589