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CGCXXABI.h
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1 //===----- CGCXXABI.h - Interface to C++ ABIs -------------------*- C++ -*-===//
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 an abstract class for C++ code generation. Concrete subclasses
10 // of this implement code generation for specific C++ ABIs.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LIB_CODEGEN_CGCXXABI_H
15 #define LLVM_CLANG_LIB_CODEGEN_CGCXXABI_H
16 
17 #include "CodeGenFunction.h"
18 #include "clang/Basic/LLVM.h"
19 
20 namespace llvm {
21 class Constant;
22 class Type;
23 class Value;
24 class CallInst;
25 }
26 
27 namespace clang {
28 class CastExpr;
29 class CXXConstructorDecl;
30 class CXXDestructorDecl;
31 class CXXMethodDecl;
32 class CXXRecordDecl;
33 class FieldDecl;
34 class MangleContext;
35 
36 namespace CodeGen {
37 class CGCallee;
38 class CodeGenFunction;
39 class CodeGenModule;
40 struct CatchTypeInfo;
41 
42 /// Implements C++ ABI-specific code generation functions.
43 class CGCXXABI {
44 protected:
46  std::unique_ptr<MangleContext> MangleCtx;
47 
49  : CGM(CGM), MangleCtx(CGM.getContext().createMangleContext()) {}
50 
51 protected:
53  return CGF.CXXABIThisDecl;
54  }
56  return CGF.CXXABIThisValue;
57  }
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 
69  return CGF.CXXStructorImplicitParamDecl;
70  }
72  return CGF.CXXStructorImplicitParamValue;
73  }
74 
75  /// Loads the incoming C++ this pointer as it was passed by the caller.
76  llvm::Value *loadIncomingCXXThis(CodeGenFunction &CGF);
77 
78  void setCXXABIThisValue(CodeGenFunction &CGF, llvm::Value *ThisPtr);
79 
80  ASTContext &getContext() const { return CGM.getContext(); }
81 
82  virtual bool requiresArrayCookie(const CXXDeleteExpr *E, QualType eltType);
83  virtual bool requiresArrayCookie(const CXXNewExpr *E);
84 
85  /// Determine whether there's something special about the rules of
86  /// the ABI tell us that 'this' is a complete object within the
87  /// given function. Obvious common logic like being defined on a
88  /// final class will have been taken care of by the caller.
89  virtual bool isThisCompleteObject(GlobalDecl GD) const = 0;
90 
91 public:
92 
93  virtual ~CGCXXABI();
94 
95  /// Gets the mangle context.
97  return *MangleCtx;
98  }
99 
100  /// Returns true if the given constructor or destructor is one of the
101  /// kinds that the ABI says returns 'this' (only applies when called
102  /// non-virtually for destructors).
103  ///
104  /// There currently is no way to indicate if a destructor returns 'this'
105  /// when called virtually, and code generation does not support the case.
106  virtual bool HasThisReturn(GlobalDecl GD) const { return false; }
107 
108  virtual bool hasMostDerivedReturn(GlobalDecl GD) const { return false; }
109 
110  /// Returns true if the target allows calling a function through a pointer
111  /// with a different signature than the actual function (or equivalently,
112  /// bitcasting a function or function pointer to a different function type).
113  /// In principle in the most general case this could depend on the target, the
114  /// calling convention, and the actual types of the arguments and return
115  /// value. Here it just means whether the signature mismatch could *ever* be
116  /// allowed; in other words, does the target do strict checking of signatures
117  /// for all calls.
118  virtual bool canCallMismatchedFunctionType() const { return true; }
119 
120  /// If the C++ ABI requires the given type be returned in a particular way,
121  /// this method sets RetAI and returns true.
122  virtual bool classifyReturnType(CGFunctionInfo &FI) const = 0;
123 
124  /// Specify how one should pass an argument of a record type.
126  /// Pass it using the normal C aggregate rules for the ABI, potentially
127  /// introducing extra copies and passing some or all of it in registers.
128  RAA_Default = 0,
129 
130  /// Pass it on the stack using its defined layout. The argument must be
131  /// evaluated directly into the correct stack position in the arguments area,
132  /// and the call machinery must not move it or introduce extra copies.
134 
135  /// Pass it as a pointer to temporary memory.
136  RAA_Indirect
137  };
138 
139  /// Returns true if C++ allows us to copy the memory of an object of type RD
140  /// when it is passed as an argument.
141  bool canCopyArgument(const CXXRecordDecl *RD) const;
142 
143  /// Returns how an argument of the given record type should be passed.
144  virtual RecordArgABI getRecordArgABI(const CXXRecordDecl *RD) const = 0;
145 
146  /// Returns true if the implicit 'sret' parameter comes after the implicit
147  /// 'this' parameter of C++ instance methods.
148  virtual bool isSRetParameterAfterThis() const { return false; }
149 
150  /// Find the LLVM type used to represent the given member pointer
151  /// type.
152  virtual llvm::Type *
153  ConvertMemberPointerType(const MemberPointerType *MPT);
154 
155  /// Load a member function from an object and a member function
156  /// pointer. Apply the this-adjustment and set 'This' to the
157  /// adjusted value.
158  virtual CGCallee EmitLoadOfMemberFunctionPointer(
159  CodeGenFunction &CGF, const Expr *E, Address This,
160  llvm::Value *&ThisPtrForCall, llvm::Value *MemPtr,
161  const MemberPointerType *MPT);
162 
163  /// Calculate an l-value from an object and a data member pointer.
164  virtual llvm::Value *
165  EmitMemberDataPointerAddress(CodeGenFunction &CGF, const Expr *E,
166  Address Base, llvm::Value *MemPtr,
167  const MemberPointerType *MPT);
168 
169  /// Perform a derived-to-base, base-to-derived, or bitcast member
170  /// pointer conversion.
171  virtual llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
172  const CastExpr *E,
173  llvm::Value *Src);
174 
175  /// Perform a derived-to-base, base-to-derived, or bitcast member
176  /// pointer conversion on a constant value.
177  virtual llvm::Constant *EmitMemberPointerConversion(const CastExpr *E,
178  llvm::Constant *Src);
179 
180  /// Return true if the given member pointer can be zero-initialized
181  /// (in the C++ sense) with an LLVM zeroinitializer.
182  virtual bool isZeroInitializable(const MemberPointerType *MPT);
183 
184  /// Return whether or not a member pointers type is convertible to an IR type.
185  virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const {
186  return true;
187  }
188 
189  /// Create a null member pointer of the given type.
190  virtual llvm::Constant *EmitNullMemberPointer(const MemberPointerType *MPT);
191 
192  /// Create a member pointer for the given method.
193  virtual llvm::Constant *EmitMemberFunctionPointer(const CXXMethodDecl *MD);
194 
195  /// Create a member pointer for the given field.
196  virtual llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
197  CharUnits offset);
198 
199  /// Create a member pointer for the given member pointer constant.
200  virtual llvm::Constant *EmitMemberPointer(const APValue &MP, QualType MPT);
201 
202  /// Emit a comparison between two member pointers. Returns an i1.
203  virtual llvm::Value *
204  EmitMemberPointerComparison(CodeGenFunction &CGF,
205  llvm::Value *L,
206  llvm::Value *R,
207  const MemberPointerType *MPT,
208  bool Inequality);
209 
210  /// Determine if a member pointer is non-null. Returns an i1.
211  virtual llvm::Value *
212  EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
213  llvm::Value *MemPtr,
214  const MemberPointerType *MPT);
215 
216 protected:
217  /// A utility method for computing the offset required for the given
218  /// base-to-derived or derived-to-base member-pointer conversion.
219  /// Does not handle virtual conversions (in case we ever fully
220  /// support an ABI that allows this). Returns null if no adjustment
221  /// is required.
222  llvm::Constant *getMemberPointerAdjustment(const CastExpr *E);
223 
224  /// Computes the non-virtual adjustment needed for a member pointer
225  /// conversion along an inheritance path stored in an APValue. Unlike
226  /// getMemberPointerAdjustment(), the adjustment can be negative if the path
227  /// is from a derived type to a base type.
228  CharUnits getMemberPointerPathAdjustment(const APValue &MP);
229 
230 public:
231  virtual void emitVirtualObjectDelete(CodeGenFunction &CGF,
232  const CXXDeleteExpr *DE,
233  Address Ptr, QualType ElementType,
234  const CXXDestructorDecl *Dtor) = 0;
235  virtual void emitRethrow(CodeGenFunction &CGF, bool isNoReturn) = 0;
236  virtual void emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) = 0;
237  virtual llvm::GlobalVariable *getThrowInfo(QualType T) { return nullptr; }
238 
239  /// Determine whether it's possible to emit a vtable for \p RD, even
240  /// though we do not know that the vtable has been marked as used by semantic
241  /// analysis.
242  virtual bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const = 0;
243 
244  virtual void emitBeginCatch(CodeGenFunction &CGF, const CXXCatchStmt *C) = 0;
245 
246  virtual llvm::CallInst *
247  emitTerminateForUnexpectedException(CodeGenFunction &CGF,
248  llvm::Value *Exn);
249 
250  virtual llvm::Constant *getAddrOfRTTIDescriptor(QualType Ty) = 0;
251  virtual CatchTypeInfo
252  getAddrOfCXXCatchHandlerType(QualType Ty, QualType CatchHandlerType) = 0;
253  virtual CatchTypeInfo getCatchAllTypeInfo();
254 
255  virtual bool shouldTypeidBeNullChecked(bool IsDeref,
256  QualType SrcRecordTy) = 0;
257  virtual void EmitBadTypeidCall(CodeGenFunction &CGF) = 0;
258  virtual llvm::Value *EmitTypeid(CodeGenFunction &CGF, QualType SrcRecordTy,
259  Address ThisPtr,
260  llvm::Type *StdTypeInfoPtrTy) = 0;
261 
262  virtual bool shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
263  QualType SrcRecordTy) = 0;
264 
265  virtual llvm::Value *
266  EmitDynamicCastCall(CodeGenFunction &CGF, Address Value,
267  QualType SrcRecordTy, QualType DestTy,
268  QualType DestRecordTy, llvm::BasicBlock *CastEnd) = 0;
269 
270  virtual llvm::Value *EmitDynamicCastToVoid(CodeGenFunction &CGF,
271  Address Value,
272  QualType SrcRecordTy,
273  QualType DestTy) = 0;
274 
275  virtual bool EmitBadCastCall(CodeGenFunction &CGF) = 0;
276 
277  virtual llvm::Value *GetVirtualBaseClassOffset(CodeGenFunction &CGF,
278  Address This,
279  const CXXRecordDecl *ClassDecl,
280  const CXXRecordDecl *BaseClassDecl) = 0;
281 
282  virtual llvm::BasicBlock *EmitCtorCompleteObjectHandler(CodeGenFunction &CGF,
283  const CXXRecordDecl *RD);
284 
285  /// Emit the code to initialize hidden members required
286  /// to handle virtual inheritance, if needed by the ABI.
287  virtual void
289  const CXXRecordDecl *RD) {}
290 
291  /// Emit constructor variants required by this ABI.
292  virtual void EmitCXXConstructors(const CXXConstructorDecl *D) = 0;
293 
294  /// Notes how many arguments were added to the beginning (Prefix) and ending
295  /// (Suffix) of an arg list.
296  ///
297  /// Note that Prefix actually refers to the number of args *after* the first
298  /// one: `this` arguments always come first.
300  unsigned Prefix = 0;
301  unsigned Suffix = 0;
302  AddedStructorArgs() = default;
303  AddedStructorArgs(unsigned P, unsigned S) : Prefix(P), Suffix(S) {}
304  static AddedStructorArgs prefix(unsigned N) { return {N, 0}; }
305  static AddedStructorArgs suffix(unsigned N) { return {0, N}; }
306  };
307 
308  /// Build the signature of the given constructor or destructor variant by
309  /// adding any required parameters. For convenience, ArgTys has been
310  /// initialized with the type of 'this'.
311  virtual AddedStructorArgs
312  buildStructorSignature(GlobalDecl GD,
313  SmallVectorImpl<CanQualType> &ArgTys) = 0;
314 
315  /// Returns true if the given destructor type should be emitted as a linkonce
316  /// delegating thunk, regardless of whether the dtor is defined in this TU or
317  /// not.
318  virtual bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
319  CXXDtorType DT) const = 0;
320 
321  virtual void setCXXDestructorDLLStorage(llvm::GlobalValue *GV,
322  const CXXDestructorDecl *Dtor,
323  CXXDtorType DT) const;
324 
325  virtual llvm::GlobalValue::LinkageTypes
326  getCXXDestructorLinkage(GVALinkage Linkage, const CXXDestructorDecl *Dtor,
327  CXXDtorType DT) const;
328 
329  /// Emit destructor variants required by this ABI.
330  virtual void EmitCXXDestructors(const CXXDestructorDecl *D) = 0;
331 
332  /// Get the type of the implicit "this" parameter used by a method. May return
333  /// zero if no specific type is applicable, e.g. if the ABI expects the "this"
334  /// parameter to point to some artificial offset in a complete object due to
335  /// vbases being reordered.
336  virtual const CXXRecordDecl *
338  return MD->getParent();
339  }
340 
341  /// Perform ABI-specific "this" argument adjustment required prior to
342  /// a call of a virtual function.
343  /// The "VirtualCall" argument is true iff the call itself is virtual.
344  virtual Address
346  Address This, bool VirtualCall) {
347  return This;
348  }
349 
350  /// Build a parameter variable suitable for 'this'.
351  void buildThisParam(CodeGenFunction &CGF, FunctionArgList &Params);
352 
353  /// Insert any ABI-specific implicit parameters into the parameter list for a
354  /// function. This generally involves extra data for constructors and
355  /// destructors.
356  ///
357  /// ABIs may also choose to override the return type, which has been
358  /// initialized with the type of 'this' if HasThisReturn(CGF.CurGD) is true or
359  /// the formal return type of the function otherwise.
360  virtual void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
361  FunctionArgList &Params) = 0;
362 
363  /// Get the ABI-specific "this" parameter adjustment to apply in the prologue
364  /// of a virtual function.
366  return CharUnits::Zero();
367  }
368 
369  /// Emit the ABI-specific prolog for the function.
370  virtual void EmitInstanceFunctionProlog(CodeGenFunction &CGF) = 0;
371 
372  /// Add any ABI-specific implicit arguments needed to call a constructor.
373  ///
374  /// \return The number of arguments added at the beginning and end of the
375  /// call, which is typically zero or one.
376  virtual AddedStructorArgs
377  addImplicitConstructorArgs(CodeGenFunction &CGF, const CXXConstructorDecl *D,
378  CXXCtorType Type, bool ForVirtualBase,
379  bool Delegating, CallArgList &Args) = 0;
380 
381  /// Emit the destructor call.
382  virtual void EmitDestructorCall(CodeGenFunction &CGF,
383  const CXXDestructorDecl *DD, CXXDtorType Type,
384  bool ForVirtualBase, bool Delegating,
385  Address This) = 0;
386 
387  /// Emits the VTable definitions required for the given record type.
388  virtual void emitVTableDefinitions(CodeGenVTables &CGVT,
389  const CXXRecordDecl *RD) = 0;
390 
391  /// Checks if ABI requires extra virtual offset for vtable field.
392  virtual bool
393  isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
394  CodeGenFunction::VPtr Vptr) = 0;
395 
396  /// Checks if ABI requires to initialize vptrs for given dynamic class.
397  virtual bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass) = 0;
398 
399  /// Get the address point of the vtable for the given base subobject.
400  virtual llvm::Constant *
401  getVTableAddressPoint(BaseSubobject Base,
402  const CXXRecordDecl *VTableClass) = 0;
403 
404  /// Get the address point of the vtable for the given base subobject while
405  /// building a constructor or a destructor.
406  virtual llvm::Value *
407  getVTableAddressPointInStructor(CodeGenFunction &CGF, const CXXRecordDecl *RD,
408  BaseSubobject Base,
409  const CXXRecordDecl *NearestVBase) = 0;
410 
411  /// Get the address point of the vtable for the given base subobject while
412  /// building a constexpr.
413  virtual llvm::Constant *
414  getVTableAddressPointForConstExpr(BaseSubobject Base,
415  const CXXRecordDecl *VTableClass) = 0;
416 
417  /// Get the address of the vtable for the given record decl which should be
418  /// used for the vptr at the given offset in RD.
419  virtual llvm::GlobalVariable *getAddrOfVTable(const CXXRecordDecl *RD,
420  CharUnits VPtrOffset) = 0;
421 
422  /// Build a virtual function pointer in the ABI-specific way.
423  virtual CGCallee getVirtualFunctionPointer(CodeGenFunction &CGF,
424  GlobalDecl GD, Address This,
425  llvm::Type *Ty,
426  SourceLocation Loc) = 0;
427 
428  /// Emit the ABI-specific virtual destructor call.
429  virtual llvm::Value *
430  EmitVirtualDestructorCall(CodeGenFunction &CGF, const CXXDestructorDecl *Dtor,
431  CXXDtorType DtorType, Address This,
432  const CXXMemberCallExpr *CE) = 0;
433 
435  GlobalDecl GD,
436  CallArgList &CallArgs) {}
437 
438  /// Emit any tables needed to implement virtual inheritance. For Itanium,
439  /// this emits virtual table tables. For the MSVC++ ABI, this emits virtual
440  /// base tables.
441  virtual void emitVirtualInheritanceTables(const CXXRecordDecl *RD) = 0;
442 
443  virtual bool exportThunk() = 0;
444  virtual void setThunkLinkage(llvm::Function *Thunk, bool ForVTable,
445  GlobalDecl GD, bool ReturnAdjustment) = 0;
446 
447  virtual llvm::Value *performThisAdjustment(CodeGenFunction &CGF,
448  Address This,
449  const ThisAdjustment &TA) = 0;
450 
451  virtual llvm::Value *performReturnAdjustment(CodeGenFunction &CGF,
452  Address Ret,
453  const ReturnAdjustment &RA) = 0;
454 
455  virtual void EmitReturnFromThunk(CodeGenFunction &CGF,
456  RValue RV, QualType ResultType);
457 
458  virtual size_t getSrcArgforCopyCtor(const CXXConstructorDecl *,
459  FunctionArgList &Args) const = 0;
460 
461  /// Gets the offsets of all the virtual base pointers in a given class.
462  virtual std::vector<CharUnits> getVBPtrOffsets(const CXXRecordDecl *RD);
463 
464  /// Gets the pure virtual member call function.
465  virtual StringRef GetPureVirtualCallName() = 0;
466 
467  /// Gets the deleted virtual member call name.
468  virtual StringRef GetDeletedVirtualCallName() = 0;
469 
470  /**************************** Array cookies ******************************/
471 
472  /// Returns the extra size required in order to store the array
473  /// cookie for the given new-expression. May return 0 to indicate that no
474  /// array cookie is required.
475  ///
476  /// Several cases are filtered out before this method is called:
477  /// - non-array allocations never need a cookie
478  /// - calls to \::operator new(size_t, void*) never need a cookie
479  ///
480  /// \param expr - the new-expression being allocated.
481  virtual CharUnits GetArrayCookieSize(const CXXNewExpr *expr);
482 
483  /// Initialize the array cookie for the given allocation.
484  ///
485  /// \param NewPtr - a char* which is the presumed-non-null
486  /// return value of the allocation function
487  /// \param NumElements - the computed number of elements,
488  /// potentially collapsed from the multidimensional array case;
489  /// always a size_t
490  /// \param ElementType - the base element allocated type,
491  /// i.e. the allocated type after stripping all array types
492  virtual Address InitializeArrayCookie(CodeGenFunction &CGF,
493  Address NewPtr,
494  llvm::Value *NumElements,
495  const CXXNewExpr *expr,
496  QualType ElementType);
497 
498  /// Reads the array cookie associated with the given pointer,
499  /// if it has one.
500  ///
501  /// \param Ptr - a pointer to the first element in the array
502  /// \param ElementType - the base element type of elements of the array
503  /// \param NumElements - an out parameter which will be initialized
504  /// with the number of elements allocated, or zero if there is no
505  /// cookie
506  /// \param AllocPtr - an out parameter which will be initialized
507  /// with a char* pointing to the address returned by the allocation
508  /// function
509  /// \param CookieSize - an out parameter which will be initialized
510  /// with the size of the cookie, or zero if there is no cookie
511  virtual void ReadArrayCookie(CodeGenFunction &CGF, Address Ptr,
512  const CXXDeleteExpr *expr,
513  QualType ElementType, llvm::Value *&NumElements,
514  llvm::Value *&AllocPtr, CharUnits &CookieSize);
515 
516  /// Return whether the given global decl needs a VTT parameter.
517  virtual bool NeedsVTTParameter(GlobalDecl GD);
518 
519 protected:
520  /// Returns the extra size required in order to store the array
521  /// cookie for the given type. Assumes that an array cookie is
522  /// required.
523  virtual CharUnits getArrayCookieSizeImpl(QualType elementType);
524 
525  /// Reads the array cookie for an allocation which is known to have one.
526  /// This is called by the standard implementation of ReadArrayCookie.
527  ///
528  /// \param ptr - a pointer to the allocation made for an array, as a char*
529  /// \param cookieSize - the computed cookie size of an array
530  ///
531  /// Other parameters are as above.
532  ///
533  /// \return a size_t
534  virtual llvm::Value *readArrayCookieImpl(CodeGenFunction &IGF, Address ptr,
535  CharUnits cookieSize);
536 
537 public:
538 
539  /*************************** Static local guards ****************************/
540 
541  /// Emits the guarded initializer and destructor setup for the given
542  /// variable, given that it couldn't be emitted as a constant.
543  /// If \p PerformInit is false, the initialization has been folded to a
544  /// constant and should not be performed.
545  ///
546  /// The variable may be:
547  /// - a static local variable
548  /// - a static data member of a class template instantiation
549  virtual void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
550  llvm::GlobalVariable *DeclPtr,
551  bool PerformInit) = 0;
552 
553  /// Emit code to force the execution of a destructor during global
554  /// teardown. The default implementation of this uses atexit.
555  ///
556  /// \param Dtor - a function taking a single pointer argument
557  /// \param Addr - a pointer to pass to the destructor function.
558  virtual void registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
559  llvm::FunctionCallee Dtor,
560  llvm::Constant *Addr) = 0;
561 
562  /*************************** thread_local initialization ********************/
563 
564  /// Emits ABI-required functions necessary to initialize thread_local
565  /// variables in this translation unit.
566  ///
567  /// \param CXXThreadLocals - The thread_local declarations in this translation
568  /// unit.
569  /// \param CXXThreadLocalInits - If this translation unit contains any
570  /// non-constant initialization or non-trivial destruction for
571  /// thread_local variables, a list of functions to perform the
572  /// initialization.
573  virtual void EmitThreadLocalInitFuncs(
574  CodeGenModule &CGM, ArrayRef<const VarDecl *> CXXThreadLocals,
575  ArrayRef<llvm::Function *> CXXThreadLocalInits,
576  ArrayRef<const VarDecl *> CXXThreadLocalInitVars) = 0;
577 
578  // Determine if references to thread_local global variables can be made
579  // directly or require access through a thread wrapper function.
580  virtual bool usesThreadWrapperFunction() const = 0;
581 
582  /// Emit a reference to a non-local thread_local variable (including
583  /// triggering the initialization of all thread_local variables in its
584  /// translation unit).
585  virtual LValue EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF,
586  const VarDecl *VD,
587  QualType LValType) = 0;
588 
589  /// Emit a single constructor/destructor with the given type from a C++
590  /// constructor Decl.
591  virtual void emitCXXStructor(GlobalDecl GD) = 0;
592 
593  /// Load a vtable from This, an object of polymorphic type RD, or from one of
594  /// its virtual bases if it does not have its own vtable. Returns the vtable
595  /// and the class from which the vtable was loaded.
596  virtual std::pair<llvm::Value *, const CXXRecordDecl *>
597  LoadVTablePtr(CodeGenFunction &CGF, Address This,
598  const CXXRecordDecl *RD) = 0;
599 };
600 
601 // Create an instance of a C++ ABI class:
602 
603 /// Creates an Itanium-family ABI.
605 
606 /// Creates a Microsoft-family ABI.
608 
610  llvm::CatchPadInst *CPI;
611 
612  CatchRetScope(llvm::CatchPadInst *CPI) : CPI(CPI) {}
613 
614  void Emit(CodeGenFunction &CGF, Flags flags) override {
615  llvm::BasicBlock *BB = CGF.createBasicBlock("catchret.dest");
616  CGF.Builder.CreateCatchRet(CPI, BB);
617  CGF.EmitBlock(BB);
618  }
619 };
620 }
621 }
622 
623 #endif
A (possibly-)qualified type.
Definition: Type.h:639
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:29
virtual Address adjustThisArgumentForVirtualFunctionCall(CodeGenFunction &CGF, GlobalDecl GD, Address This, bool VirtualCall)
Perform ABI-specific "this" argument adjustment required prior to a call of a virtual function...
Definition: CGCXXABI.h:345
StringRef P
The base class of the type hierarchy.
Definition: Type.h:1414
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2491
llvm::Value *& getStructorImplicitParamValue(CodeGenFunction &CGF)
Definition: CGCXXABI.h:71
Represents a variable declaration or definition.
Definition: Decl.h:812
const internal::VariadicDynCastAllOfMatcher< Stmt, Expr > expr
Matches expressions.
A this pointer adjustment.
Definition: ABI.h:107
A C++ throw-expression (C++ [except.throw]).
Definition: ExprCXX.h:1056
Linkage
Describes the different kinds of linkage (C++ [basic.link], C99 6.2.2) that an entity may have...
Definition: Linkage.h:23
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
A return adjustment.
Definition: ABI.h:41
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:37
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
virtual bool hasMostDerivedReturn(GlobalDecl GD) const
Definition: CGCXXABI.h:108
CodeGenModule & CGM
Definition: CGCXXABI.h:45
ImplicitParamDecl * getThisDecl(CodeGenFunction &CGF)
Definition: CGCXXABI.h:52
llvm::BasicBlock * createBasicBlock(const Twine &name="", llvm::Function *parent=nullptr, llvm::BasicBlock *before=nullptr)
createBasicBlock - Create an LLVM basic block.
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:3041
virtual bool canCallMismatchedFunctionType() const
Returns true if the target allows calling a function through a pointer with a different signature tha...
Definition: CGCXXABI.h:118
RValue - This trivial value class is used to represent the result of an expression that is evaluated...
Definition: CGValue.h:38
ImplicitParamDecl *& getStructorImplicitParamDecl(CodeGenFunction &CGF)
Definition: CGCXXABI.h:68
virtual bool HasThisReturn(GlobalDecl GD) const
Returns true if the given constructor or destructor is one of the kinds that the ABI says returns &#39;th...
Definition: CGCXXABI.h:106
CXXDtorType
C++ destructor types.
Definition: ABI.h:33
This represents one expression.
Definition: Expr.h:108
Represents a C++ destructor within a class.
Definition: DeclCXX.h:2713
virtual CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD)
Get the ABI-specific "this" parameter adjustment to apply in the prologue of a virtual function...
Definition: CGCXXABI.h:365
CGCXXABI(CodeGenModule &CGM)
Definition: CGCXXABI.h:48
static bool classifyReturnType(const CGCXXABI &CXXABI, CGFunctionInfo &FI, const ABIInfo &Info)
Definition: TargetInfo.cpp:158
ASTContext & getContext() const
Definition: CGCXXABI.h:80
ASTContext & getContext() const
virtual void adjustCallArgsForDestructorThunk(CodeGenFunction &CGF, GlobalDecl GD, CallArgList &CallArgs)
Definition: CGCXXABI.h:434
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:34
CatchRetScope(llvm::CatchPadInst *CPI)
Definition: CGCXXABI.h:612
Encodes a location in the source.
Represents a new-expression for memory allocation and constructor calls, e.g: "new CXXNewExpr(foo)"...
Definition: ExprCXX.h:1989
Represents a call to a member function that may be written either with member call syntax (e...
Definition: ExprCXX.h:170
static AddedStructorArgs suffix(unsigned N)
Definition: CGCXXABI.h:305
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2048
MangleContext - Context for tracking state which persists across multiple calls to the C++ name mangl...
Definition: Mangle.h:43
An aligned address.
Definition: Address.h:24
All available information about a concrete callee.
Definition: CGCall.h:66
MangleContext & getMangleContext()
Gets the mangle context.
Definition: CGCXXABI.h:96
CGCXXABI * CreateMicrosoftCXXABI(CodeGenModule &CGM)
Creates a Microsoft-family ABI.
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
CXXCtorType
C++ constructor types.
Definition: ABI.h:24
FunctionArgList - Type for representing both the decl and type of parameters to a function...
Definition: CGCall.h:358
CGFunctionInfo - Class to encapsulate the information about a function definition.
This class organizes the cross-function state that is used while generating LLVM code.
Optional< types::ID > Type
Dataflow Directional Tag Classes.
Represents a delete expression for memory deallocation and destructor calls, e.g. ...
Definition: ExprCXX.h:2249
virtual bool isSRetParameterAfterThis() const
Returns true if the implicit &#39;sret&#39; parameter comes after the implicit &#39;this&#39; parameter of C++ instan...
Definition: CGCXXABI.h:148
static AddedStructorArgs prefix(unsigned N)
Definition: CGCXXABI.h:304
virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const
Return whether or not a member pointers type is convertible to an IR type.
Definition: CGCXXABI.h:185
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2173
A pointer to member type per C++ 8.3.3 - Pointers to members.
Definition: Type.h:2768
std::unique_ptr< MangleContext > MangleCtx
Definition: CGCXXABI.h:46
virtual void initializeHiddenVirtualInheritanceMembers(CodeGenFunction &CGF, const CXXRecordDecl *RD)
Emit the code to initialize hidden members required to handle virtual inheritance, if needed by the ABI.
Definition: CGCXXABI.h:288
Address getThisAddress(CodeGenFunction &CGF)
Definition: CGCXXABI.h:58
Implements C++ ABI-specific code generation functions.
Definition: CGCXXABI.h:43
llvm::CatchPadInst * CPI
Definition: CGCXXABI.h:610
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:38
Pass it on the stack using its defined layout.
Definition: CGCXXABI.h:133
static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT, CGCXXABI &CXXABI)
Definition: TargetInfo.cpp:139
Represents a C++ struct/union/class.
Definition: DeclCXX.h:299
CGCXXABI * CreateItaniumCXXABI(CodeGenModule &CGM)
Creates an Itanium-family ABI.
virtual const CXXRecordDecl * getThisArgumentTypeForMethod(const CXXMethodDecl *MD)
Get the type of the implicit "this" parameter used by a method.
Definition: CGCXXABI.h:337
void Emit(CodeGenFunction &CGF, Flags flags) override
Emit the cleanup.
Definition: CGCXXABI.h:614
CXXCatchStmt - This represents a C++ catch block.
Definition: StmtCXX.h:28
Struct with all information about dynamic [sub]class needed to set vptr.
GVALinkage
A more specific kind of linkage than enum Linkage.
Definition: Linkage.h:73
virtual llvm::GlobalVariable * getThrowInfo(QualType T)
Definition: CGCXXABI.h:237
LValue - This represents an lvalue references.
Definition: CGValue.h:166
Information for lazily generating a cleanup.
Definition: EHScopeStack.h:146
Notes how many arguments were added to the beginning (Prefix) and ending (Suffix) of an arg list...
Definition: CGCXXABI.h:299
RecordArgABI
Specify how one should pass an argument of a record type.
Definition: CGCXXABI.h:125
CallArgList - Type for representing both the value and type of arguments in a call.
Definition: CGCall.h:262
llvm::Value * getThisValue(CodeGenFunction &CGF)
Definition: CGCXXABI.h:55
AddedStructorArgs(unsigned P, unsigned S)
Definition: CGCXXABI.h:303