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CGCXXABI.h
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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 
21 namespace llvm {
22 class Constant;
23 class Type;
24 class Value;
25 class CallInst;
26 }
27 
28 namespace clang {
29 class CastExpr;
30 class CXXConstructorDecl;
31 class CXXDestructorDecl;
32 class CXXMethodDecl;
33 class CXXRecordDecl;
34 class FieldDecl;
35 class MangleContext;
36 
37 namespace CodeGen {
38 class CGCallee;
39 class CodeGenFunction;
40 class CodeGenModule;
41 struct CatchTypeInfo;
42 
43 /// Implements C++ ABI-specific code generation functions.
44 class CGCXXABI {
45 protected:
47  std::unique_ptr<MangleContext> MangleCtx;
48 
50  : CGM(CGM), MangleCtx(CGM.getContext().createMangleContext()) {}
51 
52 protected:
54  return CGF.CXXABIThisDecl;
55  }
57  return CGF.CXXABIThisValue;
58  }
60  return Address(CGF.CXXABIThisValue, CGF.CXXABIThisAlignment);
61  }
62 
63  /// Issue a diagnostic about unsupported features in the ABI.
64  void ErrorUnsupportedABI(CodeGenFunction &CGF, StringRef S);
65 
66  /// Get a null value for unsupported member pointers.
67  llvm::Constant *GetBogusMemberPointer(QualType T);
68 
70  return CGF.CXXStructorImplicitParamDecl;
71  }
73  return CGF.CXXStructorImplicitParamValue;
74  }
75 
76  /// Loads the incoming C++ this pointer as it was passed by the caller.
77  llvm::Value *loadIncomingCXXThis(CodeGenFunction &CGF);
78 
79  void setCXXABIThisValue(CodeGenFunction &CGF, llvm::Value *ThisPtr);
80 
81  ASTContext &getContext() const { return CGM.getContext(); }
82 
83  virtual bool requiresArrayCookie(const CXXDeleteExpr *E, QualType eltType);
84  virtual bool requiresArrayCookie(const CXXNewExpr *E);
85 
86  /// Determine whether there's something special about the rules of
87  /// the ABI tell us that 'this' is a complete object within the
88  /// given function. Obvious common logic like being defined on a
89  /// final class will have been taken care of by the caller.
90  virtual bool isThisCompleteObject(GlobalDecl GD) const = 0;
91 
92 public:
93 
94  virtual ~CGCXXABI();
95 
96  /// Gets the mangle context.
98  return *MangleCtx;
99  }
100 
101  /// Returns true if the given constructor or destructor is one of the
102  /// kinds that the ABI says returns 'this' (only applies when called
103  /// non-virtually for destructors).
104  ///
105  /// There currently is no way to indicate if a destructor returns 'this'
106  /// when called virtually, and code generation does not support the case.
107  virtual bool HasThisReturn(GlobalDecl GD) const { return false; }
108 
109  virtual bool hasMostDerivedReturn(GlobalDecl GD) const { return false; }
110 
111  /// Returns true if the target allows calling a function through a pointer
112  /// with a different signature than the actual function (or equivalently,
113  /// bitcasting a function or function pointer to a different function type).
114  /// In principle in the most general case this could depend on the target, the
115  /// calling convention, and the actual types of the arguments and return
116  /// value. Here it just means whether the signature mismatch could *ever* be
117  /// allowed; in other words, does the target do strict checking of signatures
118  /// for all calls.
119  virtual bool canCallMismatchedFunctionType() const { return true; }
120 
121  /// If the C++ ABI requires the given type be returned in a particular way,
122  /// this method sets RetAI and returns true.
123  virtual bool classifyReturnType(CGFunctionInfo &FI) const = 0;
124 
125  /// Specify how one should pass an argument of a record type.
127  /// Pass it using the normal C aggregate rules for the ABI, potentially
128  /// introducing extra copies and passing some or all of it in registers.
129  RAA_Default = 0,
130 
131  /// Pass it on the stack using its defined layout. The argument must be
132  /// evaluated directly into the correct stack position in the arguments area,
133  /// and the call machinery must not move it or introduce extra copies.
135 
136  /// Pass it as a pointer to temporary memory.
137  RAA_Indirect
138  };
139 
140  /// Returns true if C++ allows us to copy the memory of an object of type RD
141  /// when it is passed as an argument.
142  bool canCopyArgument(const CXXRecordDecl *RD) const;
143 
144  /// Returns how an argument of the given record type should be passed.
145  virtual RecordArgABI getRecordArgABI(const CXXRecordDecl *RD) const = 0;
146 
147  /// Returns true if the implicit 'sret' parameter comes after the implicit
148  /// 'this' parameter of C++ instance methods.
149  virtual bool isSRetParameterAfterThis() const { return false; }
150 
151  /// Find the LLVM type used to represent the given member pointer
152  /// type.
153  virtual llvm::Type *
154  ConvertMemberPointerType(const MemberPointerType *MPT);
155 
156  /// Load a member function from an object and a member function
157  /// pointer. Apply the this-adjustment and set 'This' to the
158  /// adjusted value.
159  virtual CGCallee EmitLoadOfMemberFunctionPointer(
160  CodeGenFunction &CGF, const Expr *E, Address This,
161  llvm::Value *&ThisPtrForCall, llvm::Value *MemPtr,
162  const MemberPointerType *MPT);
163 
164  /// Calculate an l-value from an object and a data member pointer.
165  virtual llvm::Value *
166  EmitMemberDataPointerAddress(CodeGenFunction &CGF, const Expr *E,
167  Address Base, llvm::Value *MemPtr,
168  const MemberPointerType *MPT);
169 
170  /// Perform a derived-to-base, base-to-derived, or bitcast member
171  /// pointer conversion.
172  virtual llvm::Value *EmitMemberPointerConversion(CodeGenFunction &CGF,
173  const CastExpr *E,
174  llvm::Value *Src);
175 
176  /// Perform a derived-to-base, base-to-derived, or bitcast member
177  /// pointer conversion on a constant value.
178  virtual llvm::Constant *EmitMemberPointerConversion(const CastExpr *E,
179  llvm::Constant *Src);
180 
181  /// Return true if the given member pointer can be zero-initialized
182  /// (in the C++ sense) with an LLVM zeroinitializer.
183  virtual bool isZeroInitializable(const MemberPointerType *MPT);
184 
185  /// Return whether or not a member pointers type is convertible to an IR type.
186  virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const {
187  return true;
188  }
189 
190  /// Create a null member pointer of the given type.
191  virtual llvm::Constant *EmitNullMemberPointer(const MemberPointerType *MPT);
192 
193  /// Create a member pointer for the given method.
194  virtual llvm::Constant *EmitMemberFunctionPointer(const CXXMethodDecl *MD);
195 
196  /// Create a member pointer for the given field.
197  virtual llvm::Constant *EmitMemberDataPointer(const MemberPointerType *MPT,
198  CharUnits offset);
199 
200  /// Create a member pointer for the given member pointer constant.
201  virtual llvm::Constant *EmitMemberPointer(const APValue &MP, QualType MPT);
202 
203  /// Emit a comparison between two member pointers. Returns an i1.
204  virtual llvm::Value *
205  EmitMemberPointerComparison(CodeGenFunction &CGF,
206  llvm::Value *L,
207  llvm::Value *R,
208  const MemberPointerType *MPT,
209  bool Inequality);
210 
211  /// Determine if a member pointer is non-null. Returns an i1.
212  virtual llvm::Value *
213  EmitMemberPointerIsNotNull(CodeGenFunction &CGF,
214  llvm::Value *MemPtr,
215  const MemberPointerType *MPT);
216 
217 protected:
218  /// A utility method for computing the offset required for the given
219  /// base-to-derived or derived-to-base member-pointer conversion.
220  /// Does not handle virtual conversions (in case we ever fully
221  /// support an ABI that allows this). Returns null if no adjustment
222  /// is required.
223  llvm::Constant *getMemberPointerAdjustment(const CastExpr *E);
224 
225  /// Computes the non-virtual adjustment needed for a member pointer
226  /// conversion along an inheritance path stored in an APValue. Unlike
227  /// getMemberPointerAdjustment(), the adjustment can be negative if the path
228  /// is from a derived type to a base type.
229  CharUnits getMemberPointerPathAdjustment(const APValue &MP);
230 
231 public:
232  virtual void emitVirtualObjectDelete(CodeGenFunction &CGF,
233  const CXXDeleteExpr *DE,
234  Address Ptr, QualType ElementType,
235  const CXXDestructorDecl *Dtor) = 0;
236  virtual void emitRethrow(CodeGenFunction &CGF, bool isNoReturn) = 0;
237  virtual void emitThrow(CodeGenFunction &CGF, const CXXThrowExpr *E) = 0;
238  virtual llvm::GlobalVariable *getThrowInfo(QualType T) { return nullptr; }
239 
240  /// Determine whether it's possible to emit a vtable for \p RD, even
241  /// though we do not know that the vtable has been marked as used by semantic
242  /// analysis.
243  virtual bool canSpeculativelyEmitVTable(const CXXRecordDecl *RD) const = 0;
244 
245  virtual void emitBeginCatch(CodeGenFunction &CGF, const CXXCatchStmt *C) = 0;
246 
247  virtual llvm::CallInst *
248  emitTerminateForUnexpectedException(CodeGenFunction &CGF,
249  llvm::Value *Exn);
250 
251  virtual llvm::Constant *getAddrOfRTTIDescriptor(QualType Ty) = 0;
252  virtual CatchTypeInfo
253  getAddrOfCXXCatchHandlerType(QualType Ty, QualType CatchHandlerType) = 0;
254  virtual CatchTypeInfo getCatchAllTypeInfo();
255 
256  virtual bool shouldTypeidBeNullChecked(bool IsDeref,
257  QualType SrcRecordTy) = 0;
258  virtual void EmitBadTypeidCall(CodeGenFunction &CGF) = 0;
259  virtual llvm::Value *EmitTypeid(CodeGenFunction &CGF, QualType SrcRecordTy,
260  Address ThisPtr,
261  llvm::Type *StdTypeInfoPtrTy) = 0;
262 
263  virtual bool shouldDynamicCastCallBeNullChecked(bool SrcIsPtr,
264  QualType SrcRecordTy) = 0;
265 
266  virtual llvm::Value *
267  EmitDynamicCastCall(CodeGenFunction &CGF, Address Value,
268  QualType SrcRecordTy, QualType DestTy,
269  QualType DestRecordTy, llvm::BasicBlock *CastEnd) = 0;
270 
271  virtual llvm::Value *EmitDynamicCastToVoid(CodeGenFunction &CGF,
272  Address Value,
273  QualType SrcRecordTy,
274  QualType DestTy) = 0;
275 
276  virtual bool EmitBadCastCall(CodeGenFunction &CGF) = 0;
277 
278  virtual llvm::Value *GetVirtualBaseClassOffset(CodeGenFunction &CGF,
279  Address This,
280  const CXXRecordDecl *ClassDecl,
281  const CXXRecordDecl *BaseClassDecl) = 0;
282 
283  virtual llvm::BasicBlock *EmitCtorCompleteObjectHandler(CodeGenFunction &CGF,
284  const CXXRecordDecl *RD);
285 
286  /// Emit the code to initialize hidden members required
287  /// to handle virtual inheritance, if needed by the ABI.
288  virtual void
290  const CXXRecordDecl *RD) {}
291 
292  /// Emit constructor variants required by this ABI.
293  virtual void EmitCXXConstructors(const CXXConstructorDecl *D) = 0;
294 
295  /// Notes how many arguments were added to the beginning (Prefix) and ending
296  /// (Suffix) of an arg list.
297  ///
298  /// Note that Prefix actually refers to the number of args *after* the first
299  /// one: `this` arguments always come first.
301  unsigned Prefix = 0;
302  unsigned Suffix = 0;
303  AddedStructorArgs() = default;
304  AddedStructorArgs(unsigned P, unsigned S) : Prefix(P), Suffix(S) {}
305  static AddedStructorArgs prefix(unsigned N) { return {N, 0}; }
306  static AddedStructorArgs suffix(unsigned N) { return {0, N}; }
307  };
308 
309  /// Build the signature of the given constructor or destructor variant by
310  /// adding any required parameters. For convenience, ArgTys has been
311  /// initialized with the type of 'this'.
312  virtual AddedStructorArgs
313  buildStructorSignature(const CXXMethodDecl *MD, StructorType T,
314  SmallVectorImpl<CanQualType> &ArgTys) = 0;
315 
316  /// Returns true if the given destructor type should be emitted as a linkonce
317  /// delegating thunk, regardless of whether the dtor is defined in this TU or
318  /// not.
319  virtual bool useThunkForDtorVariant(const CXXDestructorDecl *Dtor,
320  CXXDtorType DT) const = 0;
321 
322  virtual void setCXXDestructorDLLStorage(llvm::GlobalValue *GV,
323  const CXXDestructorDecl *Dtor,
324  CXXDtorType DT) const;
325 
326  virtual llvm::GlobalValue::LinkageTypes
327  getCXXDestructorLinkage(GVALinkage Linkage, const CXXDestructorDecl *Dtor,
328  CXXDtorType DT) const;
329 
330  /// Emit destructor variants required by this ABI.
331  virtual void EmitCXXDestructors(const CXXDestructorDecl *D) = 0;
332 
333  /// Get the type of the implicit "this" parameter used by a method. May return
334  /// zero if no specific type is applicable, e.g. if the ABI expects the "this"
335  /// parameter to point to some artificial offset in a complete object due to
336  /// vbases being reordered.
337  virtual const CXXRecordDecl *
339  return MD->getParent();
340  }
341 
342  /// Perform ABI-specific "this" argument adjustment required prior to
343  /// a call of a virtual function.
344  /// The "VirtualCall" argument is true iff the call itself is virtual.
345  virtual Address
347  Address This, bool VirtualCall) {
348  return This;
349  }
350 
351  /// Build a parameter variable suitable for 'this'.
352  void buildThisParam(CodeGenFunction &CGF, FunctionArgList &Params);
353 
354  /// Insert any ABI-specific implicit parameters into the parameter list for a
355  /// function. This generally involves extra data for constructors and
356  /// destructors.
357  ///
358  /// ABIs may also choose to override the return type, which has been
359  /// initialized with the type of 'this' if HasThisReturn(CGF.CurGD) is true or
360  /// the formal return type of the function otherwise.
361  virtual void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
362  FunctionArgList &Params) = 0;
363 
364  /// Get the ABI-specific "this" parameter adjustment to apply in the prologue
365  /// of a virtual function.
367  return CharUnits::Zero();
368  }
369 
370  /// Emit the ABI-specific prolog for the function.
371  virtual void EmitInstanceFunctionProlog(CodeGenFunction &CGF) = 0;
372 
373  /// Add any ABI-specific implicit arguments needed to call a constructor.
374  ///
375  /// \return The number of arguments added at the beginning and end of the
376  /// call, which is typically zero or one.
377  virtual AddedStructorArgs
378  addImplicitConstructorArgs(CodeGenFunction &CGF, const CXXConstructorDecl *D,
379  CXXCtorType Type, bool ForVirtualBase,
380  bool Delegating, CallArgList &Args) = 0;
381 
382  /// Emit the destructor call.
383  virtual void EmitDestructorCall(CodeGenFunction &CGF,
384  const CXXDestructorDecl *DD, CXXDtorType Type,
385  bool ForVirtualBase, bool Delegating,
386  Address This) = 0;
387 
388  /// Emits the VTable definitions required for the given record type.
389  virtual void emitVTableDefinitions(CodeGenVTables &CGVT,
390  const CXXRecordDecl *RD) = 0;
391 
392  /// Checks if ABI requires extra virtual offset for vtable field.
393  virtual bool
394  isVirtualOffsetNeededForVTableField(CodeGenFunction &CGF,
395  CodeGenFunction::VPtr Vptr) = 0;
396 
397  /// Checks if ABI requires to initialize vptrs for given dynamic class.
398  virtual bool doStructorsInitializeVPtrs(const CXXRecordDecl *VTableClass) = 0;
399 
400  /// Get the address point of the vtable for the given base subobject.
401  virtual llvm::Constant *
402  getVTableAddressPoint(BaseSubobject Base,
403  const CXXRecordDecl *VTableClass) = 0;
404 
405  /// Get the address point of the vtable for the given base subobject while
406  /// building a constructor or a destructor.
407  virtual llvm::Value *
408  getVTableAddressPointInStructor(CodeGenFunction &CGF, const CXXRecordDecl *RD,
409  BaseSubobject Base,
410  const CXXRecordDecl *NearestVBase) = 0;
411 
412  /// Get the address point of the vtable for the given base subobject while
413  /// building a constexpr.
414  virtual llvm::Constant *
415  getVTableAddressPointForConstExpr(BaseSubobject Base,
416  const CXXRecordDecl *VTableClass) = 0;
417 
418  /// Get the address of the vtable for the given record decl which should be
419  /// used for the vptr at the given offset in RD.
420  virtual llvm::GlobalVariable *getAddrOfVTable(const CXXRecordDecl *RD,
421  CharUnits VPtrOffset) = 0;
422 
423  /// Build a virtual function pointer in the ABI-specific way.
424  virtual CGCallee getVirtualFunctionPointer(CodeGenFunction &CGF,
425  GlobalDecl GD, Address This,
426  llvm::Type *Ty,
427  SourceLocation Loc) = 0;
428 
429  /// Emit the ABI-specific virtual destructor call.
430  virtual llvm::Value *
431  EmitVirtualDestructorCall(CodeGenFunction &CGF, const CXXDestructorDecl *Dtor,
432  CXXDtorType DtorType, Address This,
433  const CXXMemberCallExpr *CE) = 0;
434 
436  GlobalDecl GD,
437  CallArgList &CallArgs) {}
438 
439  /// Emit any tables needed to implement virtual inheritance. For Itanium,
440  /// this emits virtual table tables. For the MSVC++ ABI, this emits virtual
441  /// base tables.
442  virtual void emitVirtualInheritanceTables(const CXXRecordDecl *RD) = 0;
443 
444  virtual bool exportThunk() = 0;
445  virtual void setThunkLinkage(llvm::Function *Thunk, bool ForVTable,
446  GlobalDecl GD, bool ReturnAdjustment) = 0;
447 
448  virtual llvm::Value *performThisAdjustment(CodeGenFunction &CGF,
449  Address This,
450  const ThisAdjustment &TA) = 0;
451 
452  virtual llvm::Value *performReturnAdjustment(CodeGenFunction &CGF,
453  Address Ret,
454  const ReturnAdjustment &RA) = 0;
455 
456  virtual void EmitReturnFromThunk(CodeGenFunction &CGF,
457  RValue RV, QualType ResultType);
458 
459  virtual size_t getSrcArgforCopyCtor(const CXXConstructorDecl *,
460  FunctionArgList &Args) const = 0;
461 
462  /// Gets the offsets of all the virtual base pointers in a given class.
463  virtual std::vector<CharUnits> getVBPtrOffsets(const CXXRecordDecl *RD);
464 
465  /// Gets the pure virtual member call function.
466  virtual StringRef GetPureVirtualCallName() = 0;
467 
468  /// Gets the deleted virtual member call name.
469  virtual StringRef GetDeletedVirtualCallName() = 0;
470 
471  /**************************** Array cookies ******************************/
472 
473  /// Returns the extra size required in order to store the array
474  /// cookie for the given new-expression. May return 0 to indicate that no
475  /// array cookie is required.
476  ///
477  /// Several cases are filtered out before this method is called:
478  /// - non-array allocations never need a cookie
479  /// - calls to \::operator new(size_t, void*) never need a cookie
480  ///
481  /// \param expr - the new-expression being allocated.
482  virtual CharUnits GetArrayCookieSize(const CXXNewExpr *expr);
483 
484  /// Initialize the array cookie for the given allocation.
485  ///
486  /// \param NewPtr - a char* which is the presumed-non-null
487  /// return value of the allocation function
488  /// \param NumElements - the computed number of elements,
489  /// potentially collapsed from the multidimensional array case;
490  /// always a size_t
491  /// \param ElementType - the base element allocated type,
492  /// i.e. the allocated type after stripping all array types
493  virtual Address InitializeArrayCookie(CodeGenFunction &CGF,
494  Address NewPtr,
495  llvm::Value *NumElements,
496  const CXXNewExpr *expr,
497  QualType ElementType);
498 
499  /// Reads the array cookie associated with the given pointer,
500  /// if it has one.
501  ///
502  /// \param Ptr - a pointer to the first element in the array
503  /// \param ElementType - the base element type of elements of the array
504  /// \param NumElements - an out parameter which will be initialized
505  /// with the number of elements allocated, or zero if there is no
506  /// cookie
507  /// \param AllocPtr - an out parameter which will be initialized
508  /// with a char* pointing to the address returned by the allocation
509  /// function
510  /// \param CookieSize - an out parameter which will be initialized
511  /// with the size of the cookie, or zero if there is no cookie
512  virtual void ReadArrayCookie(CodeGenFunction &CGF, Address Ptr,
513  const CXXDeleteExpr *expr,
514  QualType ElementType, llvm::Value *&NumElements,
515  llvm::Value *&AllocPtr, CharUnits &CookieSize);
516 
517  /// Return whether the given global decl needs a VTT parameter.
518  virtual bool NeedsVTTParameter(GlobalDecl GD);
519 
520 protected:
521  /// Returns the extra size required in order to store the array
522  /// cookie for the given type. Assumes that an array cookie is
523  /// required.
524  virtual CharUnits getArrayCookieSizeImpl(QualType elementType);
525 
526  /// Reads the array cookie for an allocation which is known to have one.
527  /// This is called by the standard implementation of ReadArrayCookie.
528  ///
529  /// \param ptr - a pointer to the allocation made for an array, as a char*
530  /// \param cookieSize - the computed cookie size of an array
531  ///
532  /// Other parameters are as above.
533  ///
534  /// \return a size_t
535  virtual llvm::Value *readArrayCookieImpl(CodeGenFunction &IGF, Address ptr,
536  CharUnits cookieSize);
537 
538 public:
539 
540  /*************************** Static local guards ****************************/
541 
542  /// Emits the guarded initializer and destructor setup for the given
543  /// variable, given that it couldn't be emitted as a constant.
544  /// If \p PerformInit is false, the initialization has been folded to a
545  /// constant and should not be performed.
546  ///
547  /// The variable may be:
548  /// - a static local variable
549  /// - a static data member of a class template instantiation
550  virtual void EmitGuardedInit(CodeGenFunction &CGF, const VarDecl &D,
551  llvm::GlobalVariable *DeclPtr,
552  bool PerformInit) = 0;
553 
554  /// Emit code to force the execution of a destructor during global
555  /// teardown. The default implementation of this uses atexit.
556  ///
557  /// \param Dtor - a function taking a single pointer argument
558  /// \param Addr - a pointer to pass to the destructor function.
559  virtual void registerGlobalDtor(CodeGenFunction &CGF, const VarDecl &D,
560  llvm::Constant *Dtor,
561  llvm::Constant *Addr) = 0;
562 
563  /*************************** thread_local initialization ********************/
564 
565  /// Emits ABI-required functions necessary to initialize thread_local
566  /// variables in this translation unit.
567  ///
568  /// \param CXXThreadLocals - The thread_local declarations in this translation
569  /// unit.
570  /// \param CXXThreadLocalInits - If this translation unit contains any
571  /// non-constant initialization or non-trivial destruction for
572  /// thread_local variables, a list of functions to perform the
573  /// initialization.
574  virtual void EmitThreadLocalInitFuncs(
575  CodeGenModule &CGM, ArrayRef<const VarDecl *> CXXThreadLocals,
576  ArrayRef<llvm::Function *> CXXThreadLocalInits,
577  ArrayRef<const VarDecl *> CXXThreadLocalInitVars) = 0;
578 
579  // Determine if references to thread_local global variables can be made
580  // directly or require access through a thread wrapper function.
581  virtual bool usesThreadWrapperFunction() const = 0;
582 
583  /// Emit a reference to a non-local thread_local variable (including
584  /// triggering the initialization of all thread_local variables in its
585  /// translation unit).
586  virtual LValue EmitThreadLocalVarDeclLValue(CodeGenFunction &CGF,
587  const VarDecl *VD,
588  QualType LValType) = 0;
589 
590  /// Emit a single constructor/destructor with the given type from a C++
591  /// constructor Decl.
592  virtual void emitCXXStructor(const CXXMethodDecl *MD, StructorType Type) = 0;
593 
594  /// Load a vtable from This, an object of polymorphic type RD, or from one of
595  /// its virtual bases if it does not have its own vtable. Returns the vtable
596  /// and the class from which the vtable was loaded.
597  virtual std::pair<llvm::Value *, const CXXRecordDecl *>
598  LoadVTablePtr(CodeGenFunction &CGF, Address This,
599  const CXXRecordDecl *RD) = 0;
600 };
601 
602 // Create an instance of a C++ ABI class:
603 
604 /// Creates an Itanium-family ABI.
606 
607 /// Creates a Microsoft-family ABI.
609 
611  llvm::CatchPadInst *CPI;
612 
613  CatchRetScope(llvm::CatchPadInst *CPI) : CPI(CPI) {}
614 
615  void Emit(CodeGenFunction &CGF, Flags flags) override {
616  llvm::BasicBlock *BB = CGF.createBasicBlock("catchret.dest");
617  CGF.Builder.CreateCatchRet(CPI, BB);
618  CGF.EmitBlock(BB);
619  }
620 };
621 }
622 }
623 
624 #endif
A (possibly-)qualified type.
Definition: Type.h:641
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
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:346
StringRef P
The base class of the type hierarchy.
Definition: Type.h:1414
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2483
llvm::Value *& getStructorImplicitParamValue(CodeGenFunction &CGF)
Definition: CGCXXABI.h:72
Represents a variable declaration or definition.
Definition: Decl.h:820
const internal::VariadicDynCastAllOfMatcher< Stmt, Expr > expr
Matches expressions.
A this pointer adjustment.
Definition: ABI.h:108
A C++ throw-expression (C++ [except.throw]).
Definition: ExprCXX.h:1094
Linkage
Describes the different kinds of linkage (C++ [basic.link], C99 6.2.2) that an entity may have...
Definition: Linkage.h:24
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:153
A return adjustment.
Definition: ABI.h:42
CharUnits - This is an opaque type for sizes expressed in character units.
Definition: CharUnits.h:38
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
virtual bool hasMostDerivedReturn(GlobalDecl GD) const
Definition: CGCXXABI.h:109
CodeGenModule & CGM
Definition: CGCXXABI.h:46
ImplicitParamDecl * getThisDecl(CodeGenFunction &CGF)
Definition: CGCXXABI.h:53
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:2935
virtual bool canCallMismatchedFunctionType() const
Returns true if the target allows calling a function through a pointer with a different signature tha...
Definition: CGCXXABI.h:119
RValue - This trivial value class is used to represent the result of an expression that is evaluated...
Definition: CGValue.h:39
ImplicitParamDecl *& getStructorImplicitParamDecl(CodeGenFunction &CGF)
Definition: CGCXXABI.h:69
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:107
CXXDtorType
C++ destructor types.
Definition: ABI.h:34
Expr - This represents one expression.
Definition: Expr.h:106
Represents a C++ destructor within a class.
Definition: DeclCXX.h:2705
virtual CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD)
Get the ABI-specific "this" parameter adjustment to apply in the prologue of a virtual function...
Definition: CGCXXABI.h:366
CGCXXABI(CodeGenModule &CGM)
Definition: CGCXXABI.h:49
static bool classifyReturnType(const CGCXXABI &CXXABI, CGFunctionInfo &FI, const ABIInfo &Info)
Definition: TargetInfo.cpp:159
ASTContext & getContext() const
Definition: CGCXXABI.h:81
ASTContext & getContext() const
virtual void adjustCallArgsForDestructorThunk(CodeGenFunction &CGF, GlobalDecl GD, CallArgList &CallArgs)
Definition: CGCXXABI.h:435
GlobalDecl - represents a global declaration.
Definition: GlobalDecl.h:35
CatchRetScope(llvm::CatchPadInst *CPI)
Definition: CGCXXABI.h:613
Encodes a location in the source.
Represents a new-expression for memory allocation and constructor calls, e.g: "new CXXNewExpr(foo)"...
Definition: ExprCXX.h:2041
Represents a call to a member function that may be written either with member call syntax (e...
Definition: ExprCXX.h:172
static AddedStructorArgs suffix(unsigned N)
Definition: CGCXXABI.h:306
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2051
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:25
All available information about a concrete callee.
Definition: CGCall.h:67
MangleContext & getMangleContext()
Gets the mangle context.
Definition: CGCXXABI.h:97
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:38
CXXCtorType
C++ constructor types.
Definition: ABI.h:25
FunctionArgList - Type for representing both the decl and type of parameters to a function...
Definition: CGCall.h:356
CGFunctionInfo - Class to encapsulate the information about a function definition.
This class organizes the cross-function state that is used while generating LLVM code.
Dataflow Directional Tag Classes.
Represents a delete expression for memory deallocation and destructor calls, e.g. ...
Definition: ExprCXX.h:2280
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:149
static AddedStructorArgs prefix(unsigned N)
Definition: CGCXXABI.h:305
virtual bool isMemberPointerConvertible(const MemberPointerType *MPT) const
Return whether or not a member pointers type is convertible to an IR type.
Definition: CGCXXABI.h:186
const CXXRecordDecl * getParent() const
Returns the parent of this method declaration, which is the class in which this method is defined...
Definition: DeclCXX.h:2171
A pointer to member type per C++ 8.3.3 - Pointers to members.
Definition: Type.h:2716
std::unique_ptr< MangleContext > MangleCtx
Definition: CGCXXABI.h:47
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:289
Address getThisAddress(CodeGenFunction &CGF)
Definition: CGCXXABI.h:59
Implements C++ ABI-specific code generation functions.
Definition: CGCXXABI.h:44
llvm::CatchPadInst * CPI
Definition: CGCXXABI.h:611
void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false)
EmitBlock - Emit the given block.
Definition: CGStmt.cpp:445
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:134
static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT, CGCXXABI &CXXABI)
Definition: TargetInfo.cpp:140
Represents a C++ struct/union/class.
Definition: DeclCXX.h:308
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:338
void Emit(CodeGenFunction &CGF, Flags flags) override
Emit the cleanup.
Definition: CGCXXABI.h:615
CXXCatchStmt - This represents a C++ catch block.
Definition: StmtCXX.h:29
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:74
virtual llvm::GlobalVariable * getThrowInfo(QualType T)
Definition: CGCXXABI.h:238
LValue - This represents an lvalue references.
Definition: CGValue.h:167
Information for lazily generating a cleanup.
Definition: EHScopeStack.h:147
Notes how many arguments were added to the beginning (Prefix) and ending (Suffix) of an arg list...
Definition: CGCXXABI.h:300
RecordArgABI
Specify how one should pass an argument of a record type.
Definition: CGCXXABI.h:126
CallArgList - Type for representing both the value and type of arguments in a call.
Definition: CGCall.h:260
llvm::Value * getThisValue(CodeGenFunction &CGF)
Definition: CGCXXABI.h:56
AddedStructorArgs(unsigned P, unsigned S)
Definition: CGCXXABI.h:304