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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 how an argument of the given record type should be passed.
140  virtual RecordArgABI getRecordArgABI(const CXXRecordDecl *RD) const = 0;
141 
142  /// Returns true if the implicit 'sret' parameter comes after the implicit
143  /// 'this' parameter of C++ instance methods.
144  virtual bool isSRetParameterAfterThis() const { return false; }
145 
146  /// Find the LLVM type used to represent the given member pointer
147  /// type.
148  virtual llvm::Type *
149  ConvertMemberPointerType(const MemberPointerType *MPT);
150 
151  /// Load a member function from an object and a member function
152  /// pointer. Apply the this-adjustment and set 'This' to the
153  /// adjusted value.
154  virtual CGCallee EmitLoadOfMemberFunctionPointer(
155  CodeGenFunction &CGF, const Expr *E, Address This,
156  llvm::Value *&ThisPtrForCall, llvm::Value *MemPtr,
157  const MemberPointerType *MPT);
158 
159  /// Calculate an l-value from an object and a data member pointer.
160  virtual llvm::Value *
161  EmitMemberDataPointerAddress(CodeGenFunction &CGF, const Expr *E,
162  Address Base, llvm::Value *MemPtr,
163  const MemberPointerType *MPT);
164 
165  /// Perform a derived-to-base, base-to-derived, or bitcast member
166  /// pointer conversion.
167  virtual llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
168  const CastExpr *E,
169  llvm::Value *Src);
170 
171  /// Perform a derived-to-base, base-to-derived, or bitcast member
172  /// pointer conversion on a constant value.
173  virtual llvm::Constant *EmitMemberPointerConversion(const CastExpr *E,
174  llvm::Constant *Src);
175 
176  /// Return true if the given member pointer can be zero-initialized
177  /// (in the C++ sense) with an LLVM zeroinitializer.
178  virtual bool isZeroInitializable(const MemberPointerType *MPT);
179 
180  /// Return whether or not a member pointers type is convertible to an IR type.
181  virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const {
182  return true;
183  }
184 
185  /// Create a null member pointer of the given type.
186  virtual llvm::Constant *EmitNullMemberPointer(const MemberPointerType *MPT);
187 
188  /// Create a member pointer for the given method.
189  virtual llvm::Constant *EmitMemberFunctionPointer(const CXXMethodDecl *MD);
190 
191  /// Create a member pointer for the given field.
192  virtual llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
193  CharUnits offset);
194 
195  /// Create a member pointer for the given member pointer constant.
196  virtual llvm::Constant *EmitMemberPointer(const APValue &MP, QualType MPT);
197 
198  /// Emit a comparison between two member pointers. Returns an i1.
199  virtual llvm::Value *
200  EmitMemberPointerComparison(CodeGenFunction &CGF,
201  llvm::Value *L,
202  llvm::Value *R,
203  const MemberPointerType *MPT,
204  bool Inequality);
205 
206  /// Determine if a member pointer is non-null. Returns an i1.
207  virtual llvm::Value *
208  EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
209  llvm::Value *MemPtr,
210  const MemberPointerType *MPT);
211 
212 protected:
213  /// A utility method for computing the offset required for the given
214  /// base-to-derived or derived-to-base member-pointer conversion.
215  /// Does not handle virtual conversions (in case we ever fully
216  /// support an ABI that allows this). Returns null if no adjustment
217  /// is required.
218  llvm::Constant *getMemberPointerAdjustment(const CastExpr *E);
219 
220  /// Computes the non-virtual adjustment needed for a member pointer
221  /// conversion along an inheritance path stored in an APValue. Unlike
222  /// getMemberPointerAdjustment(), the adjustment can be negative if the path
223  /// is from a derived type to a base type.
224  CharUnits getMemberPointerPathAdjustment(const APValue &MP);
225 
226 public:
227  virtual void emitVirtualObjectDelete(CodeGenFunction &CGF,
228  const CXXDeleteExpr *DE,
229  Address Ptr, QualType ElementType,
230  const CXXDestructorDecl *Dtor) = 0;
231  virtual void emitRethrow(CodeGenFunction &CGF, bool isNoReturn) = 0;
232  virtual void emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) = 0;
233  virtual llvm::GlobalVariable *getThrowInfo(QualType T) { return nullptr; }
234 
235  /// Determine whether it's possible to emit a vtable for \p RD, even
236  /// though we do not know that the vtable has been marked as used by semantic
237  /// analysis.
238  virtual bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const = 0;
239 
240  virtual void emitBeginCatch(CodeGenFunction &CGF, const CXXCatchStmt *C) = 0;
241 
242  virtual llvm::CallInst *
243  emitTerminateForUnexpectedException(CodeGenFunction &CGF,
244  llvm::Value *Exn);
245 
246  virtual llvm::Constant *getAddrOfRTTIDescriptor(QualType Ty) = 0;
247  virtual CatchTypeInfo
248  getAddrOfCXXCatchHandlerType(QualType Ty, QualType CatchHandlerType) = 0;
249  virtual CatchTypeInfo getCatchAllTypeInfo();
250 
251  virtual bool shouldTypeidBeNullChecked(bool IsDeref,
252  QualType SrcRecordTy) = 0;
253  virtual void EmitBadTypeidCall(CodeGenFunction &CGF) = 0;
254  virtual llvm::Value *EmitTypeid(CodeGenFunction &CGF, QualType SrcRecordTy,
255  Address ThisPtr,
256  llvm::Type *StdTypeInfoPtrTy) = 0;
257 
258  virtual bool shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
259  QualType SrcRecordTy) = 0;
260 
261  virtual llvm::Value *
262  EmitDynamicCastCall(CodeGenFunction &CGF, Address Value,
263  QualType SrcRecordTy, QualType DestTy,
264  QualType DestRecordTy, llvm::BasicBlock *CastEnd) = 0;
265 
266  virtual llvm::Value *EmitDynamicCastToVoid(CodeGenFunction &CGF,
267  Address Value,
268  QualType SrcRecordTy,
269  QualType DestTy) = 0;
270 
271  virtual bool EmitBadCastCall(CodeGenFunction &CGF) = 0;
272 
273  virtual llvm::Value *GetVirtualBaseClassOffset(CodeGenFunction &CGF,
274  Address This,
275  const CXXRecordDecl *ClassDecl,
276  const CXXRecordDecl *BaseClassDecl) = 0;
277 
278  virtual llvm::BasicBlock *EmitCtorCompleteObjectHandler(CodeGenFunction &CGF,
279  const CXXRecordDecl *RD);
280 
281  /// Emit the code to initialize hidden members required
282  /// to handle virtual inheritance, if needed by the ABI.
283  virtual void
285  const CXXRecordDecl *RD) {}
286 
287  /// Emit constructor variants required by this ABI.
288  virtual void EmitCXXConstructors(const CXXConstructorDecl *D) = 0;
289 
290  /// Notes how many arguments were added to the beginning (Prefix) and ending
291  /// (Suffix) of an arg list.
292  ///
293  /// Note that Prefix actually refers to the number of args *after* the first
294  /// one: `this` arguments always come first.
296  unsigned Prefix = 0;
297  unsigned Suffix = 0;
298  AddedStructorArgs() = default;
299  AddedStructorArgs(unsigned P, unsigned S) : Prefix(P), Suffix(S) {}
300  static AddedStructorArgs prefix(unsigned N) { return {N, 0}; }
301  static AddedStructorArgs suffix(unsigned N) { return {0, N}; }
302  };
303 
304  /// Build the signature of the given constructor or destructor variant by
305  /// adding any required parameters. For convenience, ArgTys has been
306  /// initialized with the type of 'this'.
307  virtual AddedStructorArgs
308  buildStructorSignature(GlobalDecl GD,
309  SmallVectorImpl<CanQualType> &ArgTys) = 0;
310 
311  /// Returns true if the given destructor type should be emitted as a linkonce
312  /// delegating thunk, regardless of whether the dtor is defined in this TU or
313  /// not.
314  virtual bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
315  CXXDtorType DT) const = 0;
316 
317  virtual void setCXXDestructorDLLStorage(llvm::GlobalValue *GV,
318  const CXXDestructorDecl *Dtor,
319  CXXDtorType DT) const;
320 
321  virtual llvm::GlobalValue::LinkageTypes
322  getCXXDestructorLinkage(GVALinkage Linkage, const CXXDestructorDecl *Dtor,
323  CXXDtorType DT) const;
324 
325  /// Emit destructor variants required by this ABI.
326  virtual void EmitCXXDestructors(const CXXDestructorDecl *D) = 0;
327 
328  /// Get the type of the implicit "this" parameter used by a method. May return
329  /// zero if no specific type is applicable, e.g. if the ABI expects the "this"
330  /// parameter to point to some artificial offset in a complete object due to
331  /// vbases being reordered.
332  virtual const CXXRecordDecl *
334  return MD->getParent();
335  }
336 
337  /// Perform ABI-specific "this" argument adjustment required prior to
338  /// a call of a virtual function.
339  /// The "VirtualCall" argument is true iff the call itself is virtual.
340  virtual Address
342  Address This, bool VirtualCall) {
343  return This;
344  }
345 
346  /// Build a parameter variable suitable for 'this'.
347  void buildThisParam(CodeGenFunction &CGF, FunctionArgList &Params);
348 
349  /// Insert any ABI-specific implicit parameters into the parameter list for a
350  /// function. This generally involves extra data for constructors and
351  /// destructors.
352  ///
353  /// ABIs may also choose to override the return type, which has been
354  /// initialized with the type of 'this' if HasThisReturn(CGF.CurGD) is true or
355  /// the formal return type of the function otherwise.
356  virtual void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
357  FunctionArgList &Params) = 0;
358 
359  /// Get the ABI-specific "this" parameter adjustment to apply in the prologue
360  /// of a virtual function.
362  return CharUnits::Zero();
363  }
364 
365  /// Emit the ABI-specific prolog for the function.
366  virtual void EmitInstanceFunctionProlog(CodeGenFunction &CGF) = 0;
367 
368  /// Add any ABI-specific implicit arguments needed to call a constructor.
369  ///
370  /// \return The number of arguments added at the beginning and end of the
371  /// call, which is typically zero or one.
372  virtual AddedStructorArgs
373  addImplicitConstructorArgs(CodeGenFunction &CGF, const CXXConstructorDecl *D,
374  CXXCtorType Type, bool ForVirtualBase,
375  bool Delegating, CallArgList &Args) = 0;
376 
377  /// Emit the destructor call.
378  virtual void EmitDestructorCall(CodeGenFunction &CGF,
379  const CXXDestructorDecl *DD, CXXDtorType Type,
380  bool ForVirtualBase, bool Delegating,
381  Address This, QualType ThisTy) = 0;
382 
383  /// Emits the VTable definitions required for the given record type.
384  virtual void emitVTableDefinitions(CodeGenVTables &CGVT,
385  const CXXRecordDecl *RD) = 0;
386 
387  /// Checks if ABI requires extra virtual offset for vtable field.
388  virtual bool
389  isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
390  CodeGenFunction::VPtr Vptr) = 0;
391 
392  /// Checks if ABI requires to initialize vptrs for given dynamic class.
393  virtual bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass) = 0;
394 
395  /// Get the address point of the vtable for the given base subobject.
396  virtual llvm::Constant *
397  getVTableAddressPoint(BaseSubobject Base,
398  const CXXRecordDecl *VTableClass) = 0;
399 
400  /// Get the address point of the vtable for the given base subobject while
401  /// building a constructor or a destructor.
402  virtual llvm::Value *
403  getVTableAddressPointInStructor(CodeGenFunction &CGF, const CXXRecordDecl *RD,
404  BaseSubobject Base,
405  const CXXRecordDecl *NearestVBase) = 0;
406 
407  /// Get the address point of the vtable for the given base subobject while
408  /// building a constexpr.
409  virtual llvm::Constant *
410  getVTableAddressPointForConstExpr(BaseSubobject Base,
411  const CXXRecordDecl *VTableClass) = 0;
412 
413  /// Get the address of the vtable for the given record decl which should be
414  /// used for the vptr at the given offset in RD.
415  virtual llvm::GlobalVariable *getAddrOfVTable(const CXXRecordDecl *RD,
416  CharUnits VPtrOffset) = 0;
417 
418  /// Build a virtual function pointer in the ABI-specific way.
419  virtual CGCallee getVirtualFunctionPointer(CodeGenFunction &CGF,
420  GlobalDecl GD, Address This,
421  llvm::Type *Ty,
422  SourceLocation Loc) = 0;
423 
424  using DeleteOrMemberCallExpr =
425  llvm::PointerUnion<const CXXDeleteExpr *, const CXXMemberCallExpr *>;
426 
427  /// Emit the ABI-specific virtual destructor call.
428  virtual llvm::Value *EmitVirtualDestructorCall(CodeGenFunction &CGF,
429  const CXXDestructorDecl *Dtor,
430  CXXDtorType DtorType,
431  Address This,
432  DeleteOrMemberCallExpr E) = 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:643
Specialize PointerLikeTypeTraits to allow LazyGenerationalUpdatePtr to be placed into a PointerUnion...
Definition: Dominators.h:30
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:341
StringRef P
The base class of the type hierarchy.
Definition: Type.h:1421
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2574
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:1049
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:3120
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
llvm::PointerUnion< const CXXDeleteExpr *, const CXXMemberCallExpr * > DeleteOrMemberCallExpr
Definition: CGCXXABI.h:425
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:2838
virtual CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD)
Get the ABI-specific "this" parameter adjustment to apply in the prologue of a virtual function...
Definition: CGCXXABI.h:361
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:40
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:2005
static AddedStructorArgs suffix(unsigned N)
Definition: CGCXXABI.h:301
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2114
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:2265
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:144
static AddedStructorArgs prefix(unsigned N)
Definition: CGCXXABI.h:300
virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const
Return whether or not a member pointers type is convertible to an IR type.
Definition: CGCXXABI.h:181
const CXXRecordDecl * getParent() const
Return 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:2779
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:284
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:454
APValue - This class implements a discriminated union of [uninitialized] [APSInt] [APFloat]...
Definition: APValue.h:76
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:300
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:333
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:233
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:295
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:299