1	//===--- Expr.h - Classes for representing expressions ----------*- 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 file defines the Expr interface and subclasses.
10	//
11	//===----------------------------------------------------------------------===//
12
13	#ifndef LLVM_CLANG_AST_EXPR_H
14	#define LLVM_CLANG_AST_EXPR_H
15
16	#include "clang/AST/APNumericStorage.h"
17	#include "clang/AST/APValue.h"
18	#include "clang/AST/ASTVector.h"
19	#include "clang/AST/ComputeDependence.h"
20	#include "clang/AST/Decl.h"
21	#include "clang/AST/DeclAccessPair.h"
22	#include "clang/AST/DependenceFlags.h"
23	#include "clang/AST/OperationKinds.h"
24	#include "clang/AST/Stmt.h"
25	#include "clang/AST/TemplateBase.h"
26	#include "clang/AST/Type.h"
27	#include "clang/Basic/CharInfo.h"
28	#include "clang/Basic/LangOptions.h"
29	#include "clang/Basic/SyncScope.h"
30	#include "clang/Basic/TypeTraits.h"
31	#include "llvm/ADT/APFloat.h"
32	#include "llvm/ADT/APSInt.h"
33	#include "llvm/ADT/SmallVector.h"
34	#include "llvm/ADT/StringRef.h"
35	#include "llvm/ADT/iterator.h"
36	#include "llvm/ADT/iterator_range.h"
37	#include "llvm/Support/AtomicOrdering.h"
38	#include "llvm/Support/Compiler.h"
39	#include "llvm/Support/TrailingObjects.h"
40	#include <optional>
41
42	namespace clang {
43	class APValue;
44	class ASTContext;
45	class BlockDecl;
46	class CXXBaseSpecifier;
47	class CXXMemberCallExpr;
48	class CXXOperatorCallExpr;
49	class CastExpr;
50	class Decl;
51	class IdentifierInfo;
52	class MaterializeTemporaryExpr;
53	class NamedDecl;
54	class ObjCPropertyRefExpr;
55	class OpaqueValueExpr;
56	class ParmVarDecl;
57	class StringLiteral;
58	class TargetInfo;
59	class ValueDecl;
60
61	/// A simple array of base specifiers.
62	typedef SmallVector<CXXBaseSpecifier*, 4> CXXCastPath;
63
64	/// An adjustment to be made to the temporary created when emitting a
65	/// reference binding, which accesses a particular subobject of that temporary.
66	struct SubobjectAdjustment {
67	enum {
68	DerivedToBaseAdjustment,
69	FieldAdjustment,
70	MemberPointerAdjustment
71	} Kind;
72
73	struct DTB {
74	const CastExpr *BasePath;
75	const CXXRecordDecl *DerivedClass;
76	};
77
78	struct P {
79	const MemberPointerType *MPT;
80	Expr *RHS;
81	};
82
83	union {
84	struct DTB DerivedToBase;
85	const FieldDecl *Field;
86	struct P Ptr;
87	};
88
89	SubobjectAdjustment(const CastExpr *BasePath,
90	const CXXRecordDecl *DerivedClass)
91	: Kind(DerivedToBaseAdjustment) {
92	DerivedToBase.BasePath = BasePath;
93	DerivedToBase.DerivedClass = DerivedClass;
94	}
95
96	SubobjectAdjustment(const FieldDecl *Field) : Kind(FieldAdjustment) {
97	this->Field = Field;
98	}
99
100	SubobjectAdjustment(const MemberPointerType *MPT, Expr *RHS)
101	: Kind(MemberPointerAdjustment) {
102	this->Ptr.MPT = MPT;
103	this->Ptr.RHS = RHS;
104	}
105	};
106
107	/// This represents one expression. Note that Expr's are subclasses of Stmt.
108	/// This allows an expression to be transparently used any place a Stmt is
109	/// required.
110	class Expr : public ValueStmt {
111	QualType TR;
112
113	public:
114	Expr() = delete;
115	Expr(const Expr&) = delete;
116	Expr(Expr &&) = delete;
117	Expr &operator=(const Expr&) = delete;
118	Expr &operator=(Expr&&) = delete;
119
120	protected:
121	Expr(StmtClass SC, QualType T, ExprValueKind VK, ExprObjectKind OK)
122	: ValueStmt(SC) {
123	ExprBits.Dependent = 0;
124	ExprBits.ValueKind = VK;
125	ExprBits.ObjectKind = OK;
126	assert(ExprBits.ObjectKind == OK && "truncated kind");
127	setType(T);
128	}
129
130	/// Construct an empty expression.
131	explicit Expr(StmtClass SC, EmptyShell) : ValueStmt(SC) { }
132
133	/// Each concrete expr subclass is expected to compute its dependence and call
134	/// this in the constructor.
135	void setDependence(ExprDependence Deps) {
136	ExprBits.Dependent = static_cast<unsigned>(Deps);
137	}
138	friend class ASTImporter; // Sets dependence directly.
139	friend class ASTStmtReader; // Sets dependence directly.
140
141	public:
142	QualType getType() const { return TR; }
143	void setType(QualType t) {
144	// In C++, the type of an expression is always adjusted so that it
145	// will not have reference type (C++ [expr]p6). Use
146	// QualType::getNonReferenceType() to retrieve the non-reference
147	// type. Additionally, inspect Expr::isLvalue to determine whether
148	// an expression that is adjusted in this manner should be
149	// considered an lvalue.
150	assert((t.isNull() || !t->isReferenceType()) &&
151	"Expressions can't have reference type");
152
153	TR = t;
154	}
155
156	/// If this expression is an enumeration constant, return the
157	/// enumeration type under which said constant was declared.
158	/// Otherwise return the expression's type.
159	/// Note this effectively circumvents the weak typing of C's enum constants
160	QualType getEnumCoercedType(const ASTContext &Ctx) const;
161
162	ExprDependence getDependence() const {
163	return static_cast<ExprDependence>(ExprBits.Dependent);
164	}
165
166	/// Determines whether the value of this expression depends on
167	/// - a template parameter (C++ [temp.dep.constexpr])
168	/// - or an error, whose resolution is unknown
169	///
170	/// For example, the array bound of "Chars" in the following example is
171	/// value-dependent.
172	/// @code
173	/// template<int Size, char (&Chars)[Size]> struct meta_string;
174	/// @endcode
175	bool isValueDependent() const {
176	return static_cast<bool>(getDependence() & ExprDependence::Value);
177	}
178
179	/// Determines whether the type of this expression depends on
180	/// - a template parameter (C++ [temp.dep.expr], which means that its type
181	/// could change from one template instantiation to the next)
182	/// - or an error
183	///
184	/// For example, the expressions "x" and "x + y" are type-dependent in
185	/// the following code, but "y" is not type-dependent:
186	/// @code
187	/// template<typename T>
188	/// void add(T x, int y) {
189	/// x + y;
190	/// }
191	/// @endcode
192	bool isTypeDependent() const {
193	return static_cast<bool>(getDependence() & ExprDependence::Type);
194	}
195
196	/// Whether this expression is instantiation-dependent, meaning that
197	/// it depends in some way on
198	/// - a template parameter (even if neither its type nor (constant) value
199	/// can change due to the template instantiation)
200	/// - or an error
201	///
202	/// In the following example, the expression \c sizeof(sizeof(T() + T())) is
203	/// instantiation-dependent (since it involves a template parameter \c T), but
204	/// is neither type- nor value-dependent, since the type of the inner
205	/// \c sizeof is known (\c std::size_t) and therefore the size of the outer
206	/// \c sizeof is known.
207	///
208	/// \code
209	/// template<typename T>
210	/// void f(T x, T y) {
211	/// sizeof(sizeof(T() + T());
212	/// }
213	/// \endcode
214	///
215	/// \code
216	/// void func(int) {
217	/// func(); // the expression is instantiation-dependent, because it depends
218	/// // on an error.
219	/// }
220	/// \endcode
221	bool isInstantiationDependent() const {
222	return static_cast<bool>(getDependence() & ExprDependence::Instantiation);
223	}
224
225	/// Whether this expression contains an unexpanded parameter
226	/// pack (for C++11 variadic templates).
227	///
228	/// Given the following function template:
229	///
230	/// \code
231	/// template<typename F, typename ...Types>
232	/// void forward(const F &f, Types &&...args) {
233	/// f(static_cast<Types&&>(args)...);
234	/// }
235	/// \endcode
236	///
237	/// The expressions \c args and \c static_cast<Types&&>(args) both
238	/// contain parameter packs.
239	bool containsUnexpandedParameterPack() const {
240	return static_cast<bool>(getDependence() & ExprDependence::UnexpandedPack);
241	}
242
243	/// Whether this expression contains subexpressions which had errors, e.g. a
244	/// TypoExpr.
245	bool containsErrors() const {
246	return static_cast<bool>(getDependence() & ExprDependence::Error);
247	}
248
249	/// getExprLoc - Return the preferred location for the arrow when diagnosing
250	/// a problem with a generic expression.
251	SourceLocation getExprLoc() const LLVM_READONLY;
252
253	/// Determine whether an lvalue-to-rvalue conversion should implicitly be
254	/// applied to this expression if it appears as a discarded-value expression
255	/// in C++11 onwards. This applies to certain forms of volatile glvalues.
256	bool isReadIfDiscardedInCPlusPlus11() const;
257
258	/// isUnusedResultAWarning - Return true if this immediate expression should
259	/// be warned about if the result is unused. If so, fill in expr, location,
260	/// and ranges with expr to warn on and source locations/ranges appropriate
261	/// for a warning.
262	bool isUnusedResultAWarning(const Expr *&WarnExpr, SourceLocation &Loc,
263	SourceRange &R1, SourceRange &R2,
264	ASTContext &Ctx) const;
265
266	/// isLValue - True if this expression is an "l-value" according to
267	/// the rules of the current language. C and C++ give somewhat
268	/// different rules for this concept, but in general, the result of
269	/// an l-value expression identifies a specific object whereas the
270	/// result of an r-value expression is a value detached from any
271	/// specific storage.
272	///
273	/// C++11 divides the concept of "r-value" into pure r-values
274	/// ("pr-values") and so-called expiring values ("x-values"), which
275	/// identify specific objects that can be safely cannibalized for
276	/// their resources.
277	bool isLValue() const { return getValueKind() == VK_LValue; }
278	bool isPRValue() const { return getValueKind() == VK_PRValue; }
279	bool isXValue() const { return getValueKind() == VK_XValue; }
280	bool isGLValue() const { return getValueKind() != VK_PRValue; }
281
282	enum LValueClassification {
283	LV_Valid,
284	LV_NotObjectType,
285	LV_IncompleteVoidType,
286	LV_DuplicateVectorComponents,
287	LV_InvalidExpression,
288	LV_InvalidMessageExpression,
289	LV_MemberFunction,
290	LV_SubObjCPropertySetting,
291	LV_ClassTemporary,
292	LV_ArrayTemporary
293	};
294	/// Reasons why an expression might not be an l-value.
295	LValueClassification ClassifyLValue(ASTContext &Ctx) const;
296
297	enum isModifiableLvalueResult {
298	MLV_Valid,
299	MLV_NotObjectType,
300	MLV_IncompleteVoidType,
301	MLV_DuplicateVectorComponents,
302	MLV_InvalidExpression,
303	MLV_LValueCast, // Specialized form of MLV_InvalidExpression.
304	MLV_IncompleteType,
305	MLV_ConstQualified,
306	MLV_ConstQualifiedField,
307	MLV_ConstAddrSpace,
308	MLV_ArrayType,
309	MLV_NoSetterProperty,
310	MLV_MemberFunction,
311	MLV_SubObjCPropertySetting,
312	MLV_InvalidMessageExpression,
313	MLV_ClassTemporary,
314	MLV_ArrayTemporary
315	};
316	/// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type,
317	/// does not have an incomplete type, does not have a const-qualified type,
318	/// and if it is a structure or union, does not have any member (including,
319	/// recursively, any member or element of all contained aggregates or unions)
320	/// with a const-qualified type.
321	///
322	/// \param Loc [in,out] - A source location which *may* be filled
323	/// in with the location of the expression making this a
324	/// non-modifiable lvalue, if specified.
325	isModifiableLvalueResult
326	isModifiableLvalue(ASTContext &Ctx, SourceLocation *Loc = nullptr) const;
327
328	/// The return type of classify(). Represents the C++11 expression
329	/// taxonomy.
330	class Classification {
331	public:
332	/// The various classification results. Most of these mean prvalue.
333	enum Kinds {
334	CL_LValue,
335	CL_XValue,
336	CL_Function, // Functions cannot be lvalues in C.
337	CL_Void, // Void cannot be an lvalue in C.
338	CL_AddressableVoid, // Void expression whose address can be taken in C.
339	CL_DuplicateVectorComponents, // A vector shuffle with dupes.
340	CL_MemberFunction, // An expression referring to a member function
341	CL_SubObjCPropertySetting,
342	CL_ClassTemporary, // A temporary of class type, or subobject thereof.
343	CL_ArrayTemporary, // A temporary of array type.
344	CL_ObjCMessageRValue, // ObjC message is an rvalue
345	CL_PRValue // A prvalue for any other reason, of any other type
346	};
347	/// The results of modification testing.
348	enum ModifiableType {
349	CM_Untested, // testModifiable was false.
350	CM_Modifiable,
351	CM_RValue, // Not modifiable because it's an rvalue
352	CM_Function, // Not modifiable because it's a function; C++ only
353	CM_LValueCast, // Same as CM_RValue, but indicates GCC cast-as-lvalue ext
354	CM_NoSetterProperty,// Implicit assignment to ObjC property without setter
355	CM_ConstQualified,
356	CM_ConstQualifiedField,
357	CM_ConstAddrSpace,
358	CM_ArrayType,
359	CM_IncompleteType
360	};
361
362	private:
363	friend class Expr;
364
365	unsigned short Kind;
366	unsigned short Modifiable;
367
368	explicit Classification(Kinds k, ModifiableType m)
369	: Kind(k), Modifiable(m)
370	{}
371
372	public:
373	Classification() {}
374
375	Kinds getKind() const { return static_cast<Kinds>(Kind); }
376	ModifiableType getModifiable() const {
377	assert(Modifiable != CM_Untested && "Did not test for modifiability.");
378	return static_cast<ModifiableType>(Modifiable);
379	}
380	bool isLValue() const { return Kind == CL_LValue; }
381	bool isXValue() const { return Kind == CL_XValue; }
382	bool isGLValue() const { return Kind <= CL_XValue; }
383	bool isPRValue() const { return Kind >= CL_Function; }
384	bool isRValue() const { return Kind >= CL_XValue; }
385	bool isModifiable() const { return getModifiable() == CM_Modifiable; }
386
387	/// Create a simple, modifiably lvalue
388	static Classification makeSimpleLValue() {
389	return Classification(CL_LValue, CM_Modifiable);
390	}
391
392	};
393	/// Classify - Classify this expression according to the C++11
394	/// expression taxonomy.
395	///
396	/// C++11 defines ([basic.lval]) a new taxonomy of expressions to replace the
397	/// old lvalue vs rvalue. This function determines the type of expression this
398	/// is. There are three expression types:
399	/// - lvalues are classical lvalues as in C++03.
400	/// - prvalues are equivalent to rvalues in C++03.
401	/// - xvalues are expressions yielding unnamed rvalue references, e.g. a
402	/// function returning an rvalue reference.
403	/// lvalues and xvalues are collectively referred to as glvalues, while
404	/// prvalues and xvalues together form rvalues.
405	Classification Classify(ASTContext &Ctx) const {
406	return ClassifyImpl(Ctx, Loc: nullptr);
407	}
408
409	/// ClassifyModifiable - Classify this expression according to the
410	/// C++11 expression taxonomy, and see if it is valid on the left side
411	/// of an assignment.
412	///
413	/// This function extends classify in that it also tests whether the
414	/// expression is modifiable (C99 6.3.2.1p1).
415	/// \param Loc A source location that might be filled with a relevant location
416	/// if the expression is not modifiable.
417	Classification ClassifyModifiable(ASTContext &Ctx, SourceLocation &Loc) const{
418	return ClassifyImpl(Ctx, Loc: &Loc);
419	}
420
421	/// Returns the set of floating point options that apply to this expression.
422	/// Only meaningful for operations on floating point values.
423	FPOptions getFPFeaturesInEffect(const LangOptions &LO) const;
424
425	/// getValueKindForType - Given a formal return or parameter type,
426	/// give its value kind.
427	static ExprValueKind getValueKindForType(QualType T) {
428	if (const ReferenceType *RT = T->getAs<ReferenceType>())
429	return (isa<LValueReferenceType>(Val: RT)
430	? VK_LValue
431	: (RT->getPointeeType()->isFunctionType()
432	? VK_LValue : VK_XValue));
433	return VK_PRValue;
434	}
435
436	/// getValueKind - The value kind that this expression produces.
437	ExprValueKind getValueKind() const {
438	return static_cast<ExprValueKind>(ExprBits.ValueKind);
439	}
440
441	/// getObjectKind - The object kind that this expression produces.
442	/// Object kinds are meaningful only for expressions that yield an
443	/// l-value or x-value.
444	ExprObjectKind getObjectKind() const {
445	return static_cast<ExprObjectKind>(ExprBits.ObjectKind);
446	}
447
448	bool isOrdinaryOrBitFieldObject() const {
449	ExprObjectKind OK = getObjectKind();
450	return (OK == OK_Ordinary || OK == OK_BitField);
451	}
452
453	/// setValueKind - Set the value kind produced by this expression.
454	void setValueKind(ExprValueKind Cat) { ExprBits.ValueKind = Cat; }
455
456	/// setObjectKind - Set the object kind produced by this expression.
457	void setObjectKind(ExprObjectKind Cat) { ExprBits.ObjectKind = Cat; }
458
459	private:
460	Classification ClassifyImpl(ASTContext &Ctx, SourceLocation *Loc) const;
461
462	public:
463
464	/// Returns true if this expression is a gl-value that
465	/// potentially refers to a bit-field.
466	///
467	/// In C++, whether a gl-value refers to a bitfield is essentially
468	/// an aspect of the value-kind type system.
469	bool refersToBitField() const { return getObjectKind() == OK_BitField; }
470
471	/// If this expression refers to a bit-field, retrieve the
472	/// declaration of that bit-field.
473	///
474	/// Note that this returns a non-null pointer in subtly different
475	/// places than refersToBitField returns true. In particular, this can
476	/// return a non-null pointer even for r-values loaded from
477	/// bit-fields, but it will return null for a conditional bit-field.
478	FieldDecl *getSourceBitField();
479
480	/// If this expression refers to an enum constant, retrieve its declaration
481	EnumConstantDecl *getEnumConstantDecl();
482
483	const EnumConstantDecl *getEnumConstantDecl() const {
484	return const_cast<Expr *>(this)->getEnumConstantDecl();
485	}
486
487	const FieldDecl *getSourceBitField() const {
488	return const_cast<Expr*>(this)->getSourceBitField();
489	}
490
491	Decl *getReferencedDeclOfCallee();
492	const Decl *getReferencedDeclOfCallee() const {
493	return const_cast<Expr*>(this)->getReferencedDeclOfCallee();
494	}
495
496	/// If this expression is an l-value for an Objective C
497	/// property, find the underlying property reference expression.
498	const ObjCPropertyRefExpr *getObjCProperty() const;
499
500	/// Check if this expression is the ObjC 'self' implicit parameter.
501	bool isObjCSelfExpr() const;
502
503	/// Returns whether this expression refers to a vector element.
504	bool refersToVectorElement() const;
505
506	/// Returns whether this expression refers to a matrix element.
507	bool refersToMatrixElement() const {
508	return getObjectKind() == OK_MatrixComponent;
509	}
510
511	/// Returns whether this expression refers to a global register
512	/// variable.
513	bool refersToGlobalRegisterVar() const;
514
515	/// Returns whether this expression has a placeholder type.
516	bool hasPlaceholderType() const {
517	return getType()->isPlaceholderType();
518	}
519
520	/// Returns whether this expression has a specific placeholder type.
521	bool hasPlaceholderType(BuiltinType::Kind K) const {
522	assert(BuiltinType::isPlaceholderTypeKind(K));
523	if (const BuiltinType *BT = dyn_cast<BuiltinType>(Val: getType()))
524	return BT->getKind() == K;
525	return false;
526	}
527
528	/// isKnownToHaveBooleanValue - Return true if this is an integer expression
529	/// that is known to return 0 or 1. This happens for _Bool/bool expressions
530	/// but also int expressions which are produced by things like comparisons in
531	/// C.
532	///
533	/// \param Semantic If true, only return true for expressions that are known
534	/// to be semantically boolean, which might not be true even for expressions
535	/// that are known to evaluate to 0/1. For instance, reading an unsigned
536	/// bit-field with width '1' will evaluate to 0/1, but doesn't necessarily
537	/// semantically correspond to a bool.
538	bool isKnownToHaveBooleanValue(bool Semantic = true) const;
539
540	/// Check whether this array fits the idiom of a flexible array member,
541	/// depending on the value of -fstrict-flex-array.
542	/// When IgnoreTemplateOrMacroSubstitution is set, it doesn't consider sizes
543	/// resulting from the substitution of a macro or a template as special sizes.
544	bool isFlexibleArrayMemberLike(
545	ASTContext &Context,
546	LangOptions::StrictFlexArraysLevelKind StrictFlexArraysLevel,
547	bool IgnoreTemplateOrMacroSubstitution = false) const;
548
549	/// isIntegerConstantExpr - Return the value if this expression is a valid
550	/// integer constant expression. If not a valid i-c-e, return std::nullopt
551	/// and fill in Loc (if specified) with the location of the invalid
552	/// expression.
553	///
554	/// Note: This does not perform the implicit conversions required by C++11
555	/// [expr.const]p5.
556	std::optional<llvm::APSInt>
557	getIntegerConstantExpr(const ASTContext &Ctx,
558	SourceLocation *Loc = nullptr) const;
559	bool isIntegerConstantExpr(const ASTContext &Ctx,
560	SourceLocation *Loc = nullptr) const;
561
562	/// isCXX98IntegralConstantExpr - Return true if this expression is an
563	/// integral constant expression in C++98. Can only be used in C++.
564	bool isCXX98IntegralConstantExpr(const ASTContext &Ctx) const;
565
566	/// isCXX11ConstantExpr - Return true if this expression is a constant
567	/// expression in C++11. Can only be used in C++.
568	///
569	/// Note: This does not perform the implicit conversions required by C++11
570	/// [expr.const]p5.
571	bool isCXX11ConstantExpr(const ASTContext &Ctx, APValue *Result = nullptr,
572	SourceLocation *Loc = nullptr) const;
573
574	/// isPotentialConstantExpr - Return true if this function's definition
575	/// might be usable in a constant expression in C++11, if it were marked
576	/// constexpr. Return false if the function can never produce a constant
577	/// expression, along with diagnostics describing why not.
578	static bool isPotentialConstantExpr(const FunctionDecl *FD,
579	SmallVectorImpl<
580	PartialDiagnosticAt> &Diags);
581
582	/// isPotentialConstantExprUnevaluated - Return true if this expression might
583	/// be usable in a constant expression in C++11 in an unevaluated context, if
584	/// it were in function FD marked constexpr. Return false if the function can
585	/// never produce a constant expression, along with diagnostics describing
586	/// why not.
587	static bool isPotentialConstantExprUnevaluated(Expr *E,
588	const FunctionDecl *FD,
589	SmallVectorImpl<
590	PartialDiagnosticAt> &Diags);
591
592	/// isConstantInitializer - Returns true if this expression can be emitted to
593	/// IR as a constant, and thus can be used as a constant initializer in C.
594	/// If this expression is not constant and Culprit is non-null,
595	/// it is used to store the address of first non constant expr.
596	bool isConstantInitializer(ASTContext &Ctx, bool ForRef,
597	const Expr **Culprit = nullptr) const;
598
599	/// If this expression is an unambiguous reference to a single declaration,
600	/// in the style of __builtin_function_start, return that declaration. Note
601	/// that this may return a non-static member function or field in C++ if this
602	/// expression is a member pointer constant.
603	const ValueDecl *getAsBuiltinConstantDeclRef(const ASTContext &Context) const;
604
605	/// EvalStatus is a struct with detailed info about an evaluation in progress.
606	struct EvalStatus {
607	/// Whether the evaluated expression has side effects.
608	/// For example, (f() && 0) can be folded, but it still has side effects.
609	bool HasSideEffects = false;
610
611	/// Whether the evaluation hit undefined behavior.
612	/// For example, 1.0 / 0.0 can be folded to Inf, but has undefined behavior.
613	/// Likewise, INT_MAX + 1 can be folded to INT_MIN, but has UB.
614	bool HasUndefinedBehavior = false;
615
616	/// Diag - If this is non-null, it will be filled in with a stack of notes
617	/// indicating why evaluation failed (or why it failed to produce a constant
618	/// expression).
619	/// If the expression is unfoldable, the notes will indicate why it's not
620	/// foldable. If the expression is foldable, but not a constant expression,
621	/// the notes will describes why it isn't a constant expression. If the
622	/// expression *is* a constant expression, no notes will be produced.
623	///
624	/// FIXME: this causes significant performance concerns and should be
625	/// refactored at some point. Not all evaluations of the constant
626	/// expression interpreter will display the given diagnostics, this means
627	/// those kinds of uses are paying the expense of generating a diagnostic
628	/// (which may include expensive operations like converting APValue objects
629	/// to a string representation).
630	SmallVectorImpl<PartialDiagnosticAt> *Diag = nullptr;
631
632	EvalStatus() = default;
633
634	// hasSideEffects - Return true if the evaluated expression has
635	// side effects.
636	bool hasSideEffects() const {
637	return HasSideEffects;
638	}
639	};
640
641	/// EvalResult is a struct with detailed info about an evaluated expression.
642	struct EvalResult : EvalStatus {
643	/// Val - This is the value the expression can be folded to.
644	APValue Val;
645
646	// isGlobalLValue - Return true if the evaluated lvalue expression
647	// is global.
648	bool isGlobalLValue() const;
649	};
650
651	/// EvaluateAsRValue - Return true if this is a constant which we can fold to
652	/// an rvalue using any crazy technique (that has nothing to do with language
653	/// standards) that we want to, even if the expression has side-effects. If
654	/// this function returns true, it returns the folded constant in Result. If
655	/// the expression is a glvalue, an lvalue-to-rvalue conversion will be
656	/// applied.
657	bool EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx,
658	bool InConstantContext = false) const;
659
660	/// EvaluateAsBooleanCondition - Return true if this is a constant
661	/// which we can fold and convert to a boolean condition using
662	/// any crazy technique that we want to, even if the expression has
663	/// side-effects.
664	bool EvaluateAsBooleanCondition(bool &Result, const ASTContext &Ctx,
665	bool InConstantContext = false) const;
666
667	enum SideEffectsKind {
668	SE_NoSideEffects, ///< Strictly evaluate the expression.
669	SE_AllowUndefinedBehavior, ///< Allow UB that we can give a value, but not
670	///< arbitrary unmodeled side effects.
671	SE_AllowSideEffects ///< Allow any unmodeled side effect.
672	};
673
674	/// EvaluateAsInt - Return true if this is a constant which we can fold and
675	/// convert to an integer, using any crazy technique that we want to.
676	bool EvaluateAsInt(EvalResult &Result, const ASTContext &Ctx,
677	SideEffectsKind AllowSideEffects = SE_NoSideEffects,
678	bool InConstantContext = false) const;
679
680	/// EvaluateAsFloat - Return true if this is a constant which we can fold and
681	/// convert to a floating point value, using any crazy technique that we
682	/// want to.
683	bool EvaluateAsFloat(llvm::APFloat &Result, const ASTContext &Ctx,
684	SideEffectsKind AllowSideEffects = SE_NoSideEffects,
685	bool InConstantContext = false) const;
686
687	/// EvaluateAsFixedPoint - Return true if this is a constant which we can fold
688	/// and convert to a fixed point value.
689	bool EvaluateAsFixedPoint(EvalResult &Result, const ASTContext &Ctx,
690	SideEffectsKind AllowSideEffects = SE_NoSideEffects,
691	bool InConstantContext = false) const;
692
693	/// isEvaluatable - Call EvaluateAsRValue to see if this expression can be
694	/// constant folded without side-effects, but discard the result.
695	bool isEvaluatable(const ASTContext &Ctx,
696	SideEffectsKind AllowSideEffects = SE_NoSideEffects) const;
697
698	/// HasSideEffects - This routine returns true for all those expressions
699	/// which have any effect other than producing a value. Example is a function
700	/// call, volatile variable read, or throwing an exception. If
701	/// IncludePossibleEffects is false, this call treats certain expressions with
702	/// potential side effects (such as function call-like expressions,
703	/// instantiation-dependent expressions, or invocations from a macro) as not
704	/// having side effects.
705	bool HasSideEffects(const ASTContext &Ctx,
706	bool IncludePossibleEffects = true) const;
707
708	/// Determine whether this expression involves a call to any function
709	/// that is not trivial.
710	bool hasNonTrivialCall(const ASTContext &Ctx) const;
711
712	/// EvaluateKnownConstInt - Call EvaluateAsRValue and return the folded
713	/// integer. This must be called on an expression that constant folds to an
714	/// integer.
715	llvm::APSInt EvaluateKnownConstInt(
716	const ASTContext &Ctx,
717	SmallVectorImpl<PartialDiagnosticAt> *Diag = nullptr) const;
718
719	llvm::APSInt EvaluateKnownConstIntCheckOverflow(
720	const ASTContext &Ctx,
721	SmallVectorImpl<PartialDiagnosticAt> *Diag = nullptr) const;
722
723	void EvaluateForOverflow(const ASTContext &Ctx) const;
724
725	/// EvaluateAsLValue - Evaluate an expression to see if we can fold it to an
726	/// lvalue with link time known address, with no side-effects.
727	bool EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx,
728	bool InConstantContext = false) const;
729
730	/// EvaluateAsInitializer - Evaluate an expression as if it were the
731	/// initializer of the given declaration. Returns true if the initializer
732	/// can be folded to a constant, and produces any relevant notes. In C++11,
733	/// notes will be produced if the expression is not a constant expression.
734	bool EvaluateAsInitializer(APValue &Result, const ASTContext &Ctx,
735	const VarDecl *VD,
736	SmallVectorImpl<PartialDiagnosticAt> &Notes,
737	bool IsConstantInitializer) const;
738
739	/// EvaluateWithSubstitution - Evaluate an expression as if from the context
740	/// of a call to the given function with the given arguments, inside an
741	/// unevaluated context. Returns true if the expression could be folded to a
742	/// constant.
743	bool EvaluateWithSubstitution(APValue &Value, ASTContext &Ctx,
744	const FunctionDecl *Callee,
745	ArrayRef<const Expr*> Args,
746	const Expr *This = nullptr) const;
747
748	enum class ConstantExprKind {
749	/// An integer constant expression (an array bound, enumerator, case value,
750	/// bit-field width, or similar) or similar.
751	Normal,
752	/// A non-class template argument. Such a value is only used for mangling,
753	/// not for code generation, so can refer to dllimported functions.
754	NonClassTemplateArgument,
755	/// A class template argument. Such a value is used for code generation.
756	ClassTemplateArgument,
757	/// An immediate invocation. The destruction of the end result of this
758	/// evaluation is not part of the evaluation, but all other temporaries
759	/// are destroyed.
760	ImmediateInvocation,
761	};
762
763	/// Evaluate an expression that is required to be a constant expression. Does
764	/// not check the syntactic constraints for C and C++98 constant expressions.
765	bool EvaluateAsConstantExpr(
766	EvalResult &Result, const ASTContext &Ctx,
767	ConstantExprKind Kind = ConstantExprKind::Normal) const;
768
769	/// If the current Expr is a pointer, this will try to statically
770	/// determine the number of bytes available where the pointer is pointing.
771	/// Returns true if all of the above holds and we were able to figure out the
772	/// size, false otherwise.
773	///
774	/// \param Type - How to evaluate the size of the Expr, as defined by the
775	/// "type" parameter of __builtin_object_size
776	bool tryEvaluateObjectSize(uint64_t &Result, ASTContext &Ctx,
777	unsigned Type) const;
778
779	/// If the current Expr is a pointer, this will try to statically
780	/// determine the strlen of the string pointed to.
781	/// Returns true if all of the above holds and we were able to figure out the
782	/// strlen, false otherwise.
783	bool tryEvaluateStrLen(uint64_t &Result, ASTContext &Ctx) const;
784
785	bool EvaluateCharRangeAsString(std::string &Result,
786	const Expr *SizeExpression,
787	const Expr *PtrExpression, ASTContext &Ctx,
788	EvalResult &Status) const;
789
790	/// Enumeration used to describe the kind of Null pointer constant
791	/// returned from \c isNullPointerConstant().
792	enum NullPointerConstantKind {
793	/// Expression is not a Null pointer constant.
794	NPCK_NotNull = 0,
795
796	/// Expression is a Null pointer constant built from a zero integer
797	/// expression that is not a simple, possibly parenthesized, zero literal.
798	/// C++ Core Issue 903 will classify these expressions as "not pointers"
799	/// once it is adopted.
800	/// http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903
801	NPCK_ZeroExpression,
802
803	/// Expression is a Null pointer constant built from a literal zero.
804	NPCK_ZeroLiteral,
805
806	/// Expression is a C++11 nullptr.
807	NPCK_CXX11_nullptr,
808
809	/// Expression is a GNU-style __null constant.
810	NPCK_GNUNull
811	};
812
813	/// Enumeration used to describe how \c isNullPointerConstant()
814	/// should cope with value-dependent expressions.
815	enum NullPointerConstantValueDependence {
816	/// Specifies that the expression should never be value-dependent.
817	NPC_NeverValueDependent = 0,
818
819	/// Specifies that a value-dependent expression of integral or
820	/// dependent type should be considered a null pointer constant.
821	NPC_ValueDependentIsNull,
822
823	/// Specifies that a value-dependent expression should be considered
824	/// to never be a null pointer constant.
825	NPC_ValueDependentIsNotNull
826	};
827
828	/// isNullPointerConstant - C99 6.3.2.3p3 - Test if this reduces down to
829	/// a Null pointer constant. The return value can further distinguish the
830	/// kind of NULL pointer constant that was detected.
831	NullPointerConstantKind isNullPointerConstant(
832	ASTContext &Ctx,
833	NullPointerConstantValueDependence NPC) const;
834
835	/// isOBJCGCCandidate - Return true if this expression may be used in a read/
836	/// write barrier.
837	bool isOBJCGCCandidate(ASTContext &Ctx) const;
838
839	/// Returns true if this expression is a bound member function.
840	bool isBoundMemberFunction(ASTContext &Ctx) const;
841
842	/// Given an expression of bound-member type, find the type
843	/// of the member. Returns null if this is an *overloaded* bound
844	/// member expression.
845	static QualType findBoundMemberType(const Expr *expr);
846
847	/// Skip past any invisible AST nodes which might surround this
848	/// statement, such as ExprWithCleanups or ImplicitCastExpr nodes,
849	/// but also injected CXXMemberExpr and CXXConstructExpr which represent
850	/// implicit conversions.
851	Expr *IgnoreUnlessSpelledInSource();
852	const Expr *IgnoreUnlessSpelledInSource() const {
853	return const_cast<Expr *>(this)->IgnoreUnlessSpelledInSource();
854	}
855
856	/// Skip past any implicit casts which might surround this expression until
857	/// reaching a fixed point. Skips:
858	/// * ImplicitCastExpr
859	/// * FullExpr
860	Expr *IgnoreImpCasts() LLVM_READONLY;
861	const Expr *IgnoreImpCasts() const {
862	return const_cast<Expr *>(this)->IgnoreImpCasts();
863	}
864
865	/// Skip past any casts which might surround this expression until reaching
866	/// a fixed point. Skips:
867	/// * CastExpr
868	/// * FullExpr
869	/// * MaterializeTemporaryExpr
870	/// * SubstNonTypeTemplateParmExpr
871	Expr *IgnoreCasts() LLVM_READONLY;
872	const Expr *IgnoreCasts() const {
873	return const_cast<Expr *>(this)->IgnoreCasts();
874	}
875
876	/// Skip past any implicit AST nodes which might surround this expression
877	/// until reaching a fixed point. Skips:
878	/// * What IgnoreImpCasts() skips
879	/// * MaterializeTemporaryExpr
880	/// * CXXBindTemporaryExpr
881	Expr *IgnoreImplicit() LLVM_READONLY;
882	const Expr *IgnoreImplicit() const {
883	return const_cast<Expr *>(this)->IgnoreImplicit();
884	}
885
886	/// Skip past any implicit AST nodes which might surround this expression
887	/// until reaching a fixed point. Same as IgnoreImplicit, except that it
888	/// also skips over implicit calls to constructors and conversion functions.
889	///
890	/// FIXME: Should IgnoreImplicit do this?
891	Expr *IgnoreImplicitAsWritten() LLVM_READONLY;
892	const Expr *IgnoreImplicitAsWritten() const {
893	return const_cast<Expr *>(this)->IgnoreImplicitAsWritten();
894	}
895
896	/// Skip past any parentheses which might surround this expression until
897	/// reaching a fixed point. Skips:
898	/// * ParenExpr
899	/// * UnaryOperator if `UO_Extension`
900	/// * GenericSelectionExpr if `!isResultDependent()`
901	/// * ChooseExpr if `!isConditionDependent()`
902	/// * ConstantExpr
903	Expr *IgnoreParens() LLVM_READONLY;
904	const Expr *IgnoreParens() const {
905	return const_cast<Expr *>(this)->IgnoreParens();
906	}
907
908	/// Skip past any parentheses and implicit casts which might surround this
909	/// expression until reaching a fixed point.
910	/// FIXME: IgnoreParenImpCasts really ought to be equivalent to
911	/// IgnoreParens() + IgnoreImpCasts() until reaching a fixed point. However
912	/// this is currently not the case. Instead IgnoreParenImpCasts() skips:
913	/// * What IgnoreParens() skips
914	/// * What IgnoreImpCasts() skips
915	/// * MaterializeTemporaryExpr
916	/// * SubstNonTypeTemplateParmExpr
917	Expr *IgnoreParenImpCasts() LLVM_READONLY;
918	const Expr *IgnoreParenImpCasts() const {
919	return const_cast<Expr *>(this)->IgnoreParenImpCasts();
920	}
921
922	/// Skip past any parentheses and casts which might surround this expression
923	/// until reaching a fixed point. Skips:
924	/// * What IgnoreParens() skips
925	/// * What IgnoreCasts() skips
926	Expr *IgnoreParenCasts() LLVM_READONLY;
927	const Expr *IgnoreParenCasts() const {
928	return const_cast<Expr *>(this)->IgnoreParenCasts();
929	}
930
931	/// Skip conversion operators. If this Expr is a call to a conversion
932	/// operator, return the argument.
933	Expr *IgnoreConversionOperatorSingleStep() LLVM_READONLY;
934	const Expr *IgnoreConversionOperatorSingleStep() const {
935	return const_cast<Expr *>(this)->IgnoreConversionOperatorSingleStep();
936	}
937
938	/// Skip past any parentheses and lvalue casts which might surround this
939	/// expression until reaching a fixed point. Skips:
940	/// * What IgnoreParens() skips
941	/// * What IgnoreCasts() skips, except that only lvalue-to-rvalue
942	/// casts are skipped
943	/// FIXME: This is intended purely as a temporary workaround for code
944	/// that hasn't yet been rewritten to do the right thing about those
945	/// casts, and may disappear along with the last internal use.
946	Expr *IgnoreParenLValueCasts() LLVM_READONLY;
947	const Expr *IgnoreParenLValueCasts() const {
948	return const_cast<Expr *>(this)->IgnoreParenLValueCasts();
949	}
950
951	/// Skip past any parentheses and casts which do not change the value
952	/// (including ptr->int casts of the same size) until reaching a fixed point.
953	/// Skips:
954	/// * What IgnoreParens() skips
955	/// * CastExpr which do not change the value
956	/// * SubstNonTypeTemplateParmExpr
957	Expr *IgnoreParenNoopCasts(const ASTContext &Ctx) LLVM_READONLY;
958	const Expr *IgnoreParenNoopCasts(const ASTContext &Ctx) const {
959	return const_cast<Expr *>(this)->IgnoreParenNoopCasts(Ctx);
960	}
961
962	/// Skip past any parentheses and derived-to-base casts until reaching a
963	/// fixed point. Skips:
964	/// * What IgnoreParens() skips
965	/// * CastExpr which represent a derived-to-base cast (CK_DerivedToBase,
966	/// CK_UncheckedDerivedToBase and CK_NoOp)
967	Expr *IgnoreParenBaseCasts() LLVM_READONLY;
968	const Expr *IgnoreParenBaseCasts() const {
969	return const_cast<Expr *>(this)->IgnoreParenBaseCasts();
970	}
971
972	/// Determine whether this expression is a default function argument.
973	///
974	/// Default arguments are implicitly generated in the abstract syntax tree
975	/// by semantic analysis for function calls, object constructions, etc. in
976	/// C++. Default arguments are represented by \c CXXDefaultArgExpr nodes;
977	/// this routine also looks through any implicit casts to determine whether
978	/// the expression is a default argument.
979	bool isDefaultArgument() const;
980
981	/// Determine whether the result of this expression is a
982	/// temporary object of the given class type.
983	bool isTemporaryObject(ASTContext &Ctx, const CXXRecordDecl *TempTy) const;
984
985	/// Whether this expression is an implicit reference to 'this' in C++.
986	bool isImplicitCXXThis() const;
987
988	static bool hasAnyTypeDependentArguments(ArrayRef<Expr *> Exprs);
989
990	/// For an expression of class type or pointer to class type,
991	/// return the most derived class decl the expression is known to refer to.
992	///
993	/// If this expression is a cast, this method looks through it to find the
994	/// most derived decl that can be inferred from the expression.
995	/// This is valid because derived-to-base conversions have undefined
996	/// behavior if the object isn't dynamically of the derived type.
997	const CXXRecordDecl *getBestDynamicClassType() const;
998
999	/// Get the inner expression that determines the best dynamic class.
1000	/// If this is a prvalue, we guarantee that it is of the most-derived type
1001	/// for the object itself.
1002	const Expr *getBestDynamicClassTypeExpr() const;
1003
1004	/// Walk outwards from an expression we want to bind a reference to and
1005	/// find the expression whose lifetime needs to be extended. Record
1006	/// the LHSs of comma expressions and adjustments needed along the path.
1007	const Expr *skipRValueSubobjectAdjustments(
1008	SmallVectorImpl<const Expr *> &CommaLHS,
1009	SmallVectorImpl<SubobjectAdjustment> &Adjustments) const;
1010	const Expr *skipRValueSubobjectAdjustments() const {
1011	SmallVector<const Expr *, 8> CommaLHSs;
1012	SmallVector<SubobjectAdjustment, 8> Adjustments;
1013	return skipRValueSubobjectAdjustments(CommaLHS&: CommaLHSs, Adjustments);
1014	}
1015
1016	/// Checks that the two Expr's will refer to the same value as a comparison
1017	/// operand. The caller must ensure that the values referenced by the Expr's
1018	/// are not modified between E1 and E2 or the result my be invalid.
1019	static bool isSameComparisonOperand(const Expr* E1, const Expr* E2);
1020
1021	static bool classof(const Stmt *T) {
1022	return T->getStmtClass() >= firstExprConstant &&
1023	T->getStmtClass() <= lastExprConstant;
1024	}
1025	};
1026	// PointerLikeTypeTraits is specialized so it can be used with a forward-decl of
1027	// Expr. Verify that we got it right.
1028	static_assert(llvm::PointerLikeTypeTraits<Expr *>::NumLowBitsAvailable <=
1029	llvm::detail::ConstantLog2<alignof(Expr)>::value,
1030	"PointerLikeTypeTraits<Expr*> assumes too much alignment.");
1031
1032	using ConstantExprKind = Expr::ConstantExprKind;
1033
1034	//===----------------------------------------------------------------------===//
1035	// Wrapper Expressions.
1036	//===----------------------------------------------------------------------===//
1037
1038	/// FullExpr - Represents a "full-expression" node.
1039	class FullExpr : public Expr {
1040	protected:
1041	Stmt *SubExpr;
1042
1043	FullExpr(StmtClass SC, Expr *subexpr)
1044	: Expr(SC, subexpr->getType(), subexpr->getValueKind(),
1045	subexpr->getObjectKind()),
1046	SubExpr(subexpr) {
1047	setDependence(computeDependence(E: this));
1048	}
1049	FullExpr(StmtClass SC, EmptyShell Empty)
1050	: Expr(SC, Empty) {}
1051	public:
1052	const Expr *getSubExpr() const { return cast<Expr>(Val: SubExpr); }
1053	Expr *getSubExpr() { return cast<Expr>(Val: SubExpr); }
1054
1055	/// As with any mutator of the AST, be very careful when modifying an
1056	/// existing AST to preserve its invariants.
1057	void setSubExpr(Expr *E) { SubExpr = E; }
1058
1059	static bool classof(const Stmt *T) {
1060	return T->getStmtClass() >= firstFullExprConstant &&
1061	T->getStmtClass() <= lastFullExprConstant;
1062	}
1063	};
1064
1065	/// Describes the kind of result that can be tail-allocated.
1066	enum class ConstantResultStorageKind { None, Int64, APValue };
1067
1068	/// ConstantExpr - An expression that occurs in a constant context and
1069	/// optionally the result of evaluating the expression.
1070	class ConstantExpr final
1071	: public FullExpr,
1072	private llvm::TrailingObjects<ConstantExpr, APValue, uint64_t> {
1073	static_assert(std::is_same<uint64_t, llvm::APInt::WordType>::value,
1074	"ConstantExpr assumes that llvm::APInt::WordType is uint64_t "
1075	"for tail-allocated storage");
1076	friend TrailingObjects;
1077	friend class ASTStmtReader;
1078	friend class ASTStmtWriter;
1079
1080	size_t numTrailingObjects(OverloadToken<APValue>) const {
1081	return getResultStorageKind() == ConstantResultStorageKind::APValue;
1082	}
1083	size_t numTrailingObjects(OverloadToken<uint64_t>) const {
1084	return getResultStorageKind() == ConstantResultStorageKind::Int64;
1085	}
1086
1087	uint64_t &Int64Result() {
1088	assert(getResultStorageKind() == ConstantResultStorageKind::Int64 &&
1089	"invalid accessor");
1090	return *getTrailingObjects<uint64_t>();
1091	}
1092	const uint64_t &Int64Result() const {
1093	return const_cast<ConstantExpr *>(this)->Int64Result();
1094	}
1095	APValue &APValueResult() {
1096	assert(getResultStorageKind() == ConstantResultStorageKind::APValue &&
1097	"invalid accessor");
1098	return *getTrailingObjects<APValue>();
1099	}
1100	APValue &APValueResult() const {
1101	return const_cast<ConstantExpr *>(this)->APValueResult();
1102	}
1103
1104	ConstantExpr(Expr *SubExpr, ConstantResultStorageKind StorageKind,
1105	bool IsImmediateInvocation);
1106	ConstantExpr(EmptyShell Empty, ConstantResultStorageKind StorageKind);
1107
1108	public:
1109	static ConstantExpr *Create(const ASTContext &Context, Expr *E,
1110	const APValue &Result);
1111	static ConstantExpr *
1112	Create(const ASTContext &Context, Expr *E,
1113	ConstantResultStorageKind Storage = ConstantResultStorageKind::None,
1114	bool IsImmediateInvocation = false);
1115	static ConstantExpr *CreateEmpty(const ASTContext &Context,
1116	ConstantResultStorageKind StorageKind);
1117
1118	static ConstantResultStorageKind getStorageKind(const APValue &Value);
1119	static ConstantResultStorageKind getStorageKind(const Type *T,
1120	const ASTContext &Context);
1121
1122	SourceLocation getBeginLoc() const LLVM_READONLY {
1123	return SubExpr->getBeginLoc();
1124	}
1125	SourceLocation getEndLoc() const LLVM_READONLY {
1126	return SubExpr->getEndLoc();
1127	}
1128
1129	static bool classof(const Stmt *T) {
1130	return T->getStmtClass() == ConstantExprClass;
1131	}
1132
1133	void SetResult(APValue Value, const ASTContext &Context) {
1134	MoveIntoResult(Value, Context);
1135	}
1136	void MoveIntoResult(APValue &Value, const ASTContext &Context);
1137
1138	APValue::ValueKind getResultAPValueKind() const {
1139	return static_cast<APValue::ValueKind>(ConstantExprBits.APValueKind);
1140	}
1141	ConstantResultStorageKind getResultStorageKind() const {
1142	return static_cast<ConstantResultStorageKind>(ConstantExprBits.ResultKind);
1143	}
1144	bool isImmediateInvocation() const {
1145	return ConstantExprBits.IsImmediateInvocation;
1146	}
1147	bool hasAPValueResult() const {
1148	return ConstantExprBits.APValueKind != APValue::None;
1149	}
1150	APValue getAPValueResult() const;
1151	llvm::APSInt getResultAsAPSInt() const;
1152	// Iterators
1153	child_range children() { return child_range(&SubExpr, &SubExpr+1); }
1154	const_child_range children() const {
1155	return const_child_range(&SubExpr, &SubExpr + 1);
1156	}
1157	};
1158
1159	//===----------------------------------------------------------------------===//
1160	// Primary Expressions.
1161	//===----------------------------------------------------------------------===//
1162
1163	/// OpaqueValueExpr - An expression referring to an opaque object of a
1164	/// fixed type and value class. These don't correspond to concrete
1165	/// syntax; instead they're used to express operations (usually copy
1166	/// operations) on values whose source is generally obvious from
1167	/// context.
1168	class OpaqueValueExpr : public Expr {
1169	friend class ASTStmtReader;
1170	Expr *SourceExpr;
1171
1172	public:
1173	OpaqueValueExpr(SourceLocation Loc, QualType T, ExprValueKind VK,
1174	ExprObjectKind OK = OK_Ordinary, Expr *SourceExpr = nullptr)
1175	: Expr(OpaqueValueExprClass, T, VK, OK), SourceExpr(SourceExpr) {
1176	setIsUnique(false);
1177	OpaqueValueExprBits.Loc = Loc;
1178	setDependence(computeDependence(E: this));
1179	}
1180
1181	/// Given an expression which invokes a copy constructor --- i.e. a
1182	/// CXXConstructExpr, possibly wrapped in an ExprWithCleanups ---
1183	/// find the OpaqueValueExpr that's the source of the construction.
1184	static const OpaqueValueExpr *findInCopyConstruct(const Expr *expr);
1185
1186	explicit OpaqueValueExpr(EmptyShell Empty)
1187	: Expr(OpaqueValueExprClass, Empty) {}
1188
1189	/// Retrieve the location of this expression.
1190	SourceLocation getLocation() const { return OpaqueValueExprBits.Loc; }
1191
1192	SourceLocation getBeginLoc() const LLVM_READONLY {
1193	return SourceExpr ? SourceExpr->getBeginLoc() : getLocation();
1194	}
1195	SourceLocation getEndLoc() const LLVM_READONLY {
1196	return SourceExpr ? SourceExpr->getEndLoc() : getLocation();
1197	}
1198	SourceLocation getExprLoc() const LLVM_READONLY {
1199	return SourceExpr ? SourceExpr->getExprLoc() : getLocation();
1200	}
1201
1202	child_range children() {
1203	return child_range(child_iterator(), child_iterator());
1204	}
1205
1206	const_child_range children() const {
1207	return const_child_range(const_child_iterator(), const_child_iterator());
1208	}
1209
1210	/// The source expression of an opaque value expression is the
1211	/// expression which originally generated the value. This is
1212	/// provided as a convenience for analyses that don't wish to
1213	/// precisely model the execution behavior of the program.
1214	///
1215	/// The source expression is typically set when building the
1216	/// expression which binds the opaque value expression in the first
1217	/// place.
1218	Expr *getSourceExpr() const { return SourceExpr; }
1219
1220	void setIsUnique(bool V) {
1221	assert((!V || SourceExpr) &&
1222	"unique OVEs are expected to have source expressions");
1223	OpaqueValueExprBits.IsUnique = V;
1224	}
1225
1226	bool isUnique() const { return OpaqueValueExprBits.IsUnique; }
1227
1228	static bool classof(const Stmt *T) {
1229	return T->getStmtClass() == OpaqueValueExprClass;
1230	}
1231	};
1232
1233	/// A reference to a declared variable, function, enum, etc.
1234	/// [C99 6.5.1p2]
1235	///
1236	/// This encodes all the information about how a declaration is referenced
1237	/// within an expression.
1238	///
1239	/// There are several optional constructs attached to DeclRefExprs only when
1240	/// they apply in order to conserve memory. These are laid out past the end of
1241	/// the object, and flags in the DeclRefExprBitfield track whether they exist:
1242	///
1243	/// DeclRefExprBits.HasQualifier:
1244	/// Specifies when this declaration reference expression has a C++
1245	/// nested-name-specifier.
1246	/// DeclRefExprBits.HasFoundDecl:
1247	/// Specifies when this declaration reference expression has a record of
1248	/// a NamedDecl (different from the referenced ValueDecl) which was found
1249	/// during name lookup and/or overload resolution.
1250	/// DeclRefExprBits.HasTemplateKWAndArgsInfo:
1251	/// Specifies when this declaration reference expression has an explicit
1252	/// C++ template keyword and/or template argument list.
1253	/// DeclRefExprBits.RefersToEnclosingVariableOrCapture
1254	/// Specifies when this declaration reference expression (validly)
1255	/// refers to an enclosed local or a captured variable.
1256	class DeclRefExpr final
1257	: public Expr,
1258	private llvm::TrailingObjects<DeclRefExpr, NestedNameSpecifierLoc,
1259	NamedDecl *, ASTTemplateKWAndArgsInfo,
1260	TemplateArgumentLoc> {
1261	friend class ASTStmtReader;
1262	friend class ASTStmtWriter;
1263	friend TrailingObjects;
1264
1265	/// The declaration that we are referencing.
1266	ValueDecl *D;
1267
1268	/// Provides source/type location info for the declaration name
1269	/// embedded in D.
1270	DeclarationNameLoc DNLoc;
1271
1272	size_t numTrailingObjects(OverloadToken<NestedNameSpecifierLoc>) const {
1273	return hasQualifier();
1274	}
1275
1276	size_t numTrailingObjects(OverloadToken<NamedDecl *>) const {
1277	return hasFoundDecl();
1278	}
1279
1280	size_t numTrailingObjects(OverloadToken<ASTTemplateKWAndArgsInfo>) const {
1281	return hasTemplateKWAndArgsInfo();
1282	}
1283
1284	/// Test whether there is a distinct FoundDecl attached to the end of
1285	/// this DRE.
1286	bool hasFoundDecl() const { return DeclRefExprBits.HasFoundDecl; }
1287
1288	DeclRefExpr(const ASTContext &Ctx, NestedNameSpecifierLoc QualifierLoc,
1289	SourceLocation TemplateKWLoc, ValueDecl *D,
1290	bool RefersToEnlosingVariableOrCapture,
1291	const DeclarationNameInfo &NameInfo, NamedDecl *FoundD,
1292	const TemplateArgumentListInfo *TemplateArgs, QualType T,
1293	ExprValueKind VK, NonOdrUseReason NOUR);
1294
1295	/// Construct an empty declaration reference expression.
1296	explicit DeclRefExpr(EmptyShell Empty) : Expr(DeclRefExprClass, Empty) {}
1297
1298	public:
1299	DeclRefExpr(const ASTContext &Ctx, ValueDecl *D,
1300	bool RefersToEnclosingVariableOrCapture, QualType T,
1301	ExprValueKind VK, SourceLocation L,
1302	const DeclarationNameLoc &LocInfo = DeclarationNameLoc(),
1303	NonOdrUseReason NOUR = NOUR_None);
1304
1305	static DeclRefExpr *
1306	Create(const ASTContext &Context, NestedNameSpecifierLoc QualifierLoc,
1307	SourceLocation TemplateKWLoc, ValueDecl *D,
1308	bool RefersToEnclosingVariableOrCapture, SourceLocation NameLoc,
1309	QualType T, ExprValueKind VK, NamedDecl *FoundD = nullptr,
1310	const TemplateArgumentListInfo *TemplateArgs = nullptr,
1311	NonOdrUseReason NOUR = NOUR_None);
1312
1313	static DeclRefExpr *
1314	Create(const ASTContext &Context, NestedNameSpecifierLoc QualifierLoc,
1315	SourceLocation TemplateKWLoc, ValueDecl *D,
1316	bool RefersToEnclosingVariableOrCapture,
1317	const DeclarationNameInfo &NameInfo, QualType T, ExprValueKind VK,
1318	NamedDecl *FoundD = nullptr,
1319	const TemplateArgumentListInfo *TemplateArgs = nullptr,
1320	NonOdrUseReason NOUR = NOUR_None);
1321
1322	/// Construct an empty declaration reference expression.
1323	static DeclRefExpr *CreateEmpty(const ASTContext &Context, bool HasQualifier,
1324	bool HasFoundDecl,
1325	bool HasTemplateKWAndArgsInfo,
1326	unsigned NumTemplateArgs);
1327
1328	ValueDecl *getDecl() { return D; }
1329	const ValueDecl *getDecl() const { return D; }
1330	void setDecl(ValueDecl *NewD);
1331
1332	DeclarationNameInfo getNameInfo() const {
1333	return DeclarationNameInfo(getDecl()->getDeclName(), getLocation(), DNLoc);
1334	}
1335
1336	SourceLocation getLocation() const { return DeclRefExprBits.Loc; }
1337	void setLocation(SourceLocation L) { DeclRefExprBits.Loc = L; }
1338	SourceLocation getBeginLoc() const LLVM_READONLY;
1339	SourceLocation getEndLoc() const LLVM_READONLY;
1340
1341	/// Determine whether this declaration reference was preceded by a
1342	/// C++ nested-name-specifier, e.g., \c N::foo.
1343	bool hasQualifier() const { return DeclRefExprBits.HasQualifier; }
1344
1345	/// If the name was qualified, retrieves the nested-name-specifier
1346	/// that precedes the name, with source-location information.
1347	NestedNameSpecifierLoc getQualifierLoc() const {
1348	if (!hasQualifier())
1349	return NestedNameSpecifierLoc();
1350	return *getTrailingObjects<NestedNameSpecifierLoc>();
1351	}
1352
1353	/// If the name was qualified, retrieves the nested-name-specifier
1354	/// that precedes the name. Otherwise, returns NULL.
1355	NestedNameSpecifier *getQualifier() const {
1356	return getQualifierLoc().getNestedNameSpecifier();
1357	}
1358
1359	/// Get the NamedDecl through which this reference occurred.
1360	///
1361	/// This Decl may be different from the ValueDecl actually referred to in the
1362	/// presence of using declarations, etc. It always returns non-NULL, and may
1363	/// simple return the ValueDecl when appropriate.
1364
1365	NamedDecl *getFoundDecl() {
1366	return hasFoundDecl() ? *getTrailingObjects<NamedDecl *>() : D;
1367	}
1368
1369	/// Get the NamedDecl through which this reference occurred.
1370	/// See non-const variant.
1371	const NamedDecl *getFoundDecl() const {
1372	return hasFoundDecl() ? *getTrailingObjects<NamedDecl *>() : D;
1373	}
1374
1375	bool hasTemplateKWAndArgsInfo() const {
1376	return DeclRefExprBits.HasTemplateKWAndArgsInfo;
1377	}
1378
1379	/// Retrieve the location of the template keyword preceding
1380	/// this name, if any.
1381	SourceLocation getTemplateKeywordLoc() const {
1382	if (!hasTemplateKWAndArgsInfo())
1383	return SourceLocation();
1384	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->TemplateKWLoc;
1385	}
1386
1387	/// Retrieve the location of the left angle bracket starting the
1388	/// explicit template argument list following the name, if any.
1389	SourceLocation getLAngleLoc() const {
1390	if (!hasTemplateKWAndArgsInfo())
1391	return SourceLocation();
1392	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->LAngleLoc;
1393	}
1394
1395	/// Retrieve the location of the right angle bracket ending the
1396	/// explicit template argument list following the name, if any.
1397	SourceLocation getRAngleLoc() const {
1398	if (!hasTemplateKWAndArgsInfo())
1399	return SourceLocation();
1400	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->RAngleLoc;
1401	}
1402
1403	/// Determines whether the name in this declaration reference
1404	/// was preceded by the template keyword.
1405	bool hasTemplateKeyword() const { return getTemplateKeywordLoc().isValid(); }
1406
1407	/// Determines whether this declaration reference was followed by an
1408	/// explicit template argument list.
1409	bool hasExplicitTemplateArgs() const { return getLAngleLoc().isValid(); }
1410
1411	/// Copies the template arguments (if present) into the given
1412	/// structure.
1413	void copyTemplateArgumentsInto(TemplateArgumentListInfo &List) const {
1414	if (hasExplicitTemplateArgs())
1415	getTrailingObjects<ASTTemplateKWAndArgsInfo>()->copyInto(
1416	getTrailingObjects<TemplateArgumentLoc>(), List);
1417	}
1418
1419	/// Retrieve the template arguments provided as part of this
1420	/// template-id.
1421	const TemplateArgumentLoc *getTemplateArgs() const {
1422	if (!hasExplicitTemplateArgs())
1423	return nullptr;
1424	return getTrailingObjects<TemplateArgumentLoc>();
1425	}
1426
1427	/// Retrieve the number of template arguments provided as part of this
1428	/// template-id.
1429	unsigned getNumTemplateArgs() const {
1430	if (!hasExplicitTemplateArgs())
1431	return 0;
1432	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->NumTemplateArgs;
1433	}
1434
1435	ArrayRef<TemplateArgumentLoc> template_arguments() const {
1436	return {getTemplateArgs(), getNumTemplateArgs()};
1437	}
1438
1439	/// Returns true if this expression refers to a function that
1440	/// was resolved from an overloaded set having size greater than 1.
1441	bool hadMultipleCandidates() const {
1442	return DeclRefExprBits.HadMultipleCandidates;
1443	}
1444	/// Sets the flag telling whether this expression refers to
1445	/// a function that was resolved from an overloaded set having size
1446	/// greater than 1.
1447	void setHadMultipleCandidates(bool V = true) {
1448	DeclRefExprBits.HadMultipleCandidates = V;
1449	}
1450
1451	/// Is this expression a non-odr-use reference, and if so, why?
1452	NonOdrUseReason isNonOdrUse() const {
1453	return static_cast<NonOdrUseReason>(DeclRefExprBits.NonOdrUseReason);
1454	}
1455
1456	/// Does this DeclRefExpr refer to an enclosing local or a captured
1457	/// variable?
1458	bool refersToEnclosingVariableOrCapture() const {
1459	return DeclRefExprBits.RefersToEnclosingVariableOrCapture;
1460	}
1461
1462	bool isImmediateEscalating() const {
1463	return DeclRefExprBits.IsImmediateEscalating;
1464	}
1465
1466	void setIsImmediateEscalating(bool Set) {
1467	DeclRefExprBits.IsImmediateEscalating = Set;
1468	}
1469
1470	bool isCapturedByCopyInLambdaWithExplicitObjectParameter() const {
1471	return DeclRefExprBits.CapturedByCopyInLambdaWithExplicitObjectParameter;
1472	}
1473
1474	void setCapturedByCopyInLambdaWithExplicitObjectParameter(
1475	bool Set, const ASTContext &Context) {
1476	DeclRefExprBits.CapturedByCopyInLambdaWithExplicitObjectParameter = Set;
1477	setDependence(computeDependence(E: this, Ctx: Context));
1478	}
1479
1480	static bool classof(const Stmt *T) {
1481	return T->getStmtClass() == DeclRefExprClass;
1482	}
1483
1484	// Iterators
1485	child_range children() {
1486	return child_range(child_iterator(), child_iterator());
1487	}
1488
1489	const_child_range children() const {
1490	return const_child_range(const_child_iterator(), const_child_iterator());
1491	}
1492	};
1493
1494	class IntegerLiteral : public Expr, public APIntStorage {
1495	SourceLocation Loc;
1496
1497	/// Construct an empty integer literal.
1498	explicit IntegerLiteral(EmptyShell Empty)
1499	: Expr(IntegerLiteralClass, Empty) { }
1500
1501	public:
1502	// type should be IntTy, LongTy, LongLongTy, UnsignedIntTy, UnsignedLongTy,
1503	// or UnsignedLongLongTy
1504	IntegerLiteral(const ASTContext &C, const llvm::APInt &V, QualType type,
1505	SourceLocation l);
1506
1507	/// Returns a new integer literal with value 'V' and type 'type'.
1508	/// \param type - either IntTy, LongTy, LongLongTy, UnsignedIntTy,
1509	/// UnsignedLongTy, or UnsignedLongLongTy which should match the size of V
1510	/// \param V - the value that the returned integer literal contains.
1511	static IntegerLiteral *Create(const ASTContext &C, const llvm::APInt &V,
1512	QualType type, SourceLocation l);
1513	/// Returns a new empty integer literal.
1514	static IntegerLiteral *Create(const ASTContext &C, EmptyShell Empty);
1515
1516	SourceLocation getBeginLoc() const LLVM_READONLY { return Loc; }
1517	SourceLocation getEndLoc() const LLVM_READONLY { return Loc; }
1518
1519	/// Retrieve the location of the literal.
1520	SourceLocation getLocation() const { return Loc; }
1521
1522	void setLocation(SourceLocation Location) { Loc = Location; }
1523
1524	static bool classof(const Stmt *T) {
1525	return T->getStmtClass() == IntegerLiteralClass;
1526	}
1527
1528	// Iterators
1529	child_range children() {
1530	return child_range(child_iterator(), child_iterator());
1531	}
1532	const_child_range children() const {
1533	return const_child_range(const_child_iterator(), const_child_iterator());
1534	}
1535	};
1536
1537	class FixedPointLiteral : public Expr, public APIntStorage {
1538	SourceLocation Loc;
1539	unsigned Scale;
1540
1541	/// \brief Construct an empty fixed-point literal.
1542	explicit FixedPointLiteral(EmptyShell Empty)
1543	: Expr(FixedPointLiteralClass, Empty) {}
1544
1545	public:
1546	FixedPointLiteral(const ASTContext &C, const llvm::APInt &V, QualType type,
1547	SourceLocation l, unsigned Scale);
1548
1549	// Store the int as is without any bit shifting.
1550	static FixedPointLiteral *CreateFromRawInt(const ASTContext &C,
1551	const llvm::APInt &V,
1552	QualType type, SourceLocation l,
1553	unsigned Scale);
1554
1555	/// Returns an empty fixed-point literal.
1556	static FixedPointLiteral *Create(const ASTContext &C, EmptyShell Empty);
1557
1558	SourceLocation getBeginLoc() const LLVM_READONLY { return Loc; }
1559	SourceLocation getEndLoc() const LLVM_READONLY { return Loc; }
1560
1561	/// \brief Retrieve the location of the literal.
1562	SourceLocation getLocation() const { return Loc; }
1563
1564	void setLocation(SourceLocation Location) { Loc = Location; }
1565
1566	unsigned getScale() const { return Scale; }
1567	void setScale(unsigned S) { Scale = S; }
1568
1569	static bool classof(const Stmt *T) {
1570	return T->getStmtClass() == FixedPointLiteralClass;
1571	}
1572
1573	std::string getValueAsString(unsigned Radix) const;
1574
1575	// Iterators
1576	child_range children() {
1577	return child_range(child_iterator(), child_iterator());
1578	}
1579	const_child_range children() const {
1580	return const_child_range(const_child_iterator(), const_child_iterator());
1581	}
1582	};
1583
1584	enum class CharacterLiteralKind { Ascii, Wide, UTF8, UTF16, UTF32 };
1585
1586	class CharacterLiteral : public Expr {
1587	unsigned Value;
1588	SourceLocation Loc;
1589	public:
1590	// type should be IntTy
1591	CharacterLiteral(unsigned value, CharacterLiteralKind kind, QualType type,
1592	SourceLocation l)
1593	: Expr(CharacterLiteralClass, type, VK_PRValue, OK_Ordinary),
1594	Value(value), Loc(l) {
1595	CharacterLiteralBits.Kind = llvm::to_underlying(E: kind);
1596	setDependence(ExprDependence::None);
1597	}
1598
1599	/// Construct an empty character literal.
1600	CharacterLiteral(EmptyShell Empty) : Expr(CharacterLiteralClass, Empty) { }
1601
1602	SourceLocation getLocation() const { return Loc; }
1603	CharacterLiteralKind getKind() const {
1604	return static_cast<CharacterLiteralKind>(CharacterLiteralBits.Kind);
1605	}
1606
1607	SourceLocation getBeginLoc() const LLVM_READONLY { return Loc; }
1608	SourceLocation getEndLoc() const LLVM_READONLY { return Loc; }
1609
1610	unsigned getValue() const { return Value; }
1611
1612	void setLocation(SourceLocation Location) { Loc = Location; }
1613	void setKind(CharacterLiteralKind kind) {
1614	CharacterLiteralBits.Kind = llvm::to_underlying(E: kind);
1615	}
1616	void setValue(unsigned Val) { Value = Val; }
1617
1618	static bool classof(const Stmt *T) {
1619	return T->getStmtClass() == CharacterLiteralClass;
1620	}
1621
1622	static void print(unsigned val, CharacterLiteralKind Kind, raw_ostream &OS);
1623
1624	// Iterators
1625	child_range children() {
1626	return child_range(child_iterator(), child_iterator());
1627	}
1628	const_child_range children() const {
1629	return const_child_range(const_child_iterator(), const_child_iterator());
1630	}
1631	};
1632
1633	class FloatingLiteral : public Expr, private APFloatStorage {
1634	SourceLocation Loc;
1635
1636	FloatingLiteral(const ASTContext &C, const llvm::APFloat &V, bool isexact,
1637	QualType Type, SourceLocation L);
1638
1639	/// Construct an empty floating-point literal.
1640	explicit FloatingLiteral(const ASTContext &C, EmptyShell Empty);
1641
1642	public:
1643	static FloatingLiteral *Create(const ASTContext &C, const llvm::APFloat &V,
1644	bool isexact, QualType Type, SourceLocation L);
1645	static FloatingLiteral *Create(const ASTContext &C, EmptyShell Empty);
1646
1647	llvm::APFloat getValue() const {
1648	return APFloatStorage::getValue(getSemantics());
1649	}
1650	void setValue(const ASTContext &C, const llvm::APFloat &Val) {
1651	assert(&getSemantics() == &Val.getSemantics() && "Inconsistent semantics");
1652	APFloatStorage::setValue(C, Val);
1653	}
1654
1655	/// Get a raw enumeration value representing the floating-point semantics of
1656	/// this literal (32-bit IEEE, x87, ...), suitable for serialisation.
1657	llvm::APFloatBase::Semantics getRawSemantics() const {
1658	return static_cast<llvm::APFloatBase::Semantics>(
1659	FloatingLiteralBits.Semantics);
1660	}
1661
1662	/// Set the raw enumeration value representing the floating-point semantics of
1663	/// this literal (32-bit IEEE, x87, ...), suitable for serialisation.
1664	void setRawSemantics(llvm::APFloatBase::Semantics Sem) {
1665	FloatingLiteralBits.Semantics = Sem;
1666	}
1667
1668	/// Return the APFloat semantics this literal uses.
1669	const llvm::fltSemantics &getSemantics() const {
1670	return llvm::APFloatBase::EnumToSemantics(
1671	S: static_cast<llvm::APFloatBase::Semantics>(
1672	FloatingLiteralBits.Semantics));
1673	}
1674
1675	/// Set the APFloat semantics this literal uses.
1676	void setSemantics(const llvm::fltSemantics &Sem) {
1677	FloatingLiteralBits.Semantics = llvm::APFloatBase::SemanticsToEnum(Sem);
1678	}
1679
1680	bool isExact() const { return FloatingLiteralBits.IsExact; }
1681	void setExact(bool E) { FloatingLiteralBits.IsExact = E; }
1682
1683	/// getValueAsApproximateDouble - This returns the value as an inaccurate
1684	/// double. Note that this may cause loss of precision, but is useful for
1685	/// debugging dumps, etc.
1686	double getValueAsApproximateDouble() const;
1687
1688	SourceLocation getLocation() const { return Loc; }
1689	void setLocation(SourceLocation L) { Loc = L; }
1690
1691	SourceLocation getBeginLoc() const LLVM_READONLY { return Loc; }
1692	SourceLocation getEndLoc() const LLVM_READONLY { return Loc; }
1693
1694	static bool classof(const Stmt *T) {
1695	return T->getStmtClass() == FloatingLiteralClass;
1696	}
1697
1698	// Iterators
1699	child_range children() {
1700	return child_range(child_iterator(), child_iterator());
1701	}
1702	const_child_range children() const {
1703	return const_child_range(const_child_iterator(), const_child_iterator());
1704	}
1705	};
1706
1707	/// ImaginaryLiteral - We support imaginary integer and floating point literals,
1708	/// like "1.0i". We represent these as a wrapper around FloatingLiteral and
1709	/// IntegerLiteral classes. Instances of this class always have a Complex type
1710	/// whose element type matches the subexpression.
1711	///
1712	class ImaginaryLiteral : public Expr {
1713	Stmt *Val;
1714	public:
1715	ImaginaryLiteral(Expr *val, QualType Ty)
1716	: Expr(ImaginaryLiteralClass, Ty, VK_PRValue, OK_Ordinary), Val(val) {
1717	setDependence(ExprDependence::None);
1718	}
1719
1720	/// Build an empty imaginary literal.
1721	explicit ImaginaryLiteral(EmptyShell Empty)
1722	: Expr(ImaginaryLiteralClass, Empty) { }
1723
1724	const Expr *getSubExpr() const { return cast<Expr>(Val); }
1725	Expr *getSubExpr() { return cast<Expr>(Val); }
1726	void setSubExpr(Expr *E) { Val = E; }
1727
1728	SourceLocation getBeginLoc() const LLVM_READONLY {
1729	return Val->getBeginLoc();
1730	}
1731	SourceLocation getEndLoc() const LLVM_READONLY { return Val->getEndLoc(); }
1732
1733	static bool classof(const Stmt *T) {
1734	return T->getStmtClass() == ImaginaryLiteralClass;
1735	}
1736
1737	// Iterators
1738	child_range children() { return child_range(&Val, &Val+1); }
1739	const_child_range children() const {
1740	return const_child_range(&Val, &Val + 1);
1741	}
1742	};
1743
1744	enum class StringLiteralKind {
1745	Ordinary,
1746	Wide,
1747	UTF8,
1748	UTF16,
1749	UTF32,
1750	Unevaluated
1751	};
1752
1753	/// StringLiteral - This represents a string literal expression, e.g. "foo"
1754	/// or L"bar" (wide strings). The actual string data can be obtained with
1755	/// getBytes() and is NOT null-terminated. The length of the string data is
1756	/// determined by calling getByteLength().
1757	///
1758	/// The C type for a string is always a ConstantArrayType. In C++, the char
1759	/// type is const qualified, in C it is not.
1760	///
1761	/// Note that strings in C can be formed by concatenation of multiple string
1762	/// literal pptokens in translation phase #6. This keeps track of the locations
1763	/// of each of these pieces.
1764	///
1765	/// Strings in C can also be truncated and extended by assigning into arrays,
1766	/// e.g. with constructs like:
1767	/// char X[2] = "foobar";
1768	/// In this case, getByteLength() will return 6, but the string literal will
1769	/// have type "char[2]".
1770	class StringLiteral final
1771	: public Expr,
1772	private llvm::TrailingObjects<StringLiteral, unsigned, SourceLocation,
1773	char> {
1774	friend class ASTStmtReader;
1775	friend TrailingObjects;
1776
1777	/// StringLiteral is followed by several trailing objects. They are in order:
1778	///
1779	/// * A single unsigned storing the length in characters of this string. The
1780	/// length in bytes is this length times the width of a single character.
1781	/// Always present and stored as a trailing objects because storing it in
1782	/// StringLiteral would increase the size of StringLiteral by sizeof(void *)
1783	/// due to alignment requirements. If you add some data to StringLiteral,
1784	/// consider moving it inside StringLiteral.
1785	///
1786	/// * An array of getNumConcatenated() SourceLocation, one for each of the
1787	/// token this string is made of.
1788	///
1789	/// * An array of getByteLength() char used to store the string data.
1790
1791	unsigned numTrailingObjects(OverloadToken<unsigned>) const { return 1; }
1792	unsigned numTrailingObjects(OverloadToken<SourceLocation>) const {
1793	return getNumConcatenated();
1794	}
1795
1796	unsigned numTrailingObjects(OverloadToken<char>) const {
1797	return getByteLength();
1798	}
1799
1800	char *getStrDataAsChar() { return getTrailingObjects<char>(); }
1801	const char *getStrDataAsChar() const { return getTrailingObjects<char>(); }
1802
1803	const uint16_t *getStrDataAsUInt16() const {
1804	return reinterpret_cast<const uint16_t *>(getTrailingObjects<char>());
1805	}
1806
1807	const uint32_t *getStrDataAsUInt32() const {
1808	return reinterpret_cast<const uint32_t *>(getTrailingObjects<char>());
1809	}
1810
1811	/// Build a string literal.
1812	StringLiteral(const ASTContext &Ctx, StringRef Str, StringLiteralKind Kind,
1813	bool Pascal, QualType Ty, const SourceLocation *Loc,
1814	unsigned NumConcatenated);
1815
1816	/// Build an empty string literal.
1817	StringLiteral(EmptyShell Empty, unsigned NumConcatenated, unsigned Length,
1818	unsigned CharByteWidth);
1819
1820	/// Map a target and string kind to the appropriate character width.
1821	static unsigned mapCharByteWidth(TargetInfo const &Target,
1822	StringLiteralKind SK);
1823
1824	/// Set one of the string literal token.
1825	void setStrTokenLoc(unsigned TokNum, SourceLocation L) {
1826	assert(TokNum < getNumConcatenated() && "Invalid tok number");
1827	getTrailingObjects<SourceLocation>()[TokNum] = L;
1828	}
1829
1830	public:
1831	/// This is the "fully general" constructor that allows representation of
1832	/// strings formed from multiple concatenated tokens.
1833	static StringLiteral *Create(const ASTContext &Ctx, StringRef Str,
1834	StringLiteralKind Kind, bool Pascal, QualType Ty,
1835	const SourceLocation *Loc,
1836	unsigned NumConcatenated);
1837
1838	/// Simple constructor for string literals made from one token.
1839	static StringLiteral *Create(const ASTContext &Ctx, StringRef Str,
1840	StringLiteralKind Kind, bool Pascal, QualType Ty,
1841	SourceLocation Loc) {
1842	return Create(Ctx, Str, Kind, Pascal, Ty, Loc: &Loc, NumConcatenated: 1);
1843	}
1844
1845	/// Construct an empty string literal.
1846	static StringLiteral *CreateEmpty(const ASTContext &Ctx,
1847	unsigned NumConcatenated, unsigned Length,
1848	unsigned CharByteWidth);
1849
1850	StringRef getString() const {
1851	assert((isUnevaluated() || getCharByteWidth() == 1) &&
1852	"This function is used in places that assume strings use char");
1853	return StringRef(getStrDataAsChar(), getByteLength());
1854	}
1855
1856	/// Allow access to clients that need the byte representation, such as
1857	/// ASTWriterStmt::VisitStringLiteral().
1858	StringRef getBytes() const {
1859	// FIXME: StringRef may not be the right type to use as a result for this.
1860	return StringRef(getStrDataAsChar(), getByteLength());
1861	}
1862
1863	void outputString(raw_ostream &OS) const;
1864
1865	uint32_t getCodeUnit(size_t i) const {
1866	assert(i < getLength() && "out of bounds access");
1867	switch (getCharByteWidth()) {
1868	case 1:
1869	return static_cast<unsigned char>(getStrDataAsChar()[i]);
1870	case 2:
1871	return getStrDataAsUInt16()[i];
1872	case 4:
1873	return getStrDataAsUInt32()[i];
1874	}
1875	llvm_unreachable("Unsupported character width!");
1876	}
1877
1878	// Get code unit but preserve sign info.
1879	int64_t getCodeUnitS(size_t I, uint64_t BitWidth) const {
1880	int64_t V = getCodeUnit(i: I);
1881	if (isOrdinary() || isWide()) {
1882	unsigned Width = getCharByteWidth() * BitWidth;
1883	llvm::APInt AInt(Width, (uint64_t)V);
1884	V = AInt.getSExtValue();
1885	}
1886	return V;
1887	}
1888
1889	unsigned getByteLength() const { return getCharByteWidth() * getLength(); }
1890	unsigned getLength() const { return *getTrailingObjects<unsigned>(); }
1891	unsigned getCharByteWidth() const { return StringLiteralBits.CharByteWidth; }
1892
1893	StringLiteralKind getKind() const {
1894	return static_cast<StringLiteralKind>(StringLiteralBits.Kind);
1895	}
1896
1897	bool isOrdinary() const { return getKind() == StringLiteralKind::Ordinary; }
1898	bool isWide() const { return getKind() == StringLiteralKind::Wide; }
1899	bool isUTF8() const { return getKind() == StringLiteralKind::UTF8; }
1900	bool isUTF16() const { return getKind() == StringLiteralKind::UTF16; }
1901	bool isUTF32() const { return getKind() == StringLiteralKind::UTF32; }
1902	bool isUnevaluated() const { return getKind() == StringLiteralKind::Unevaluated; }
1903	bool isPascal() const { return StringLiteralBits.IsPascal; }
1904
1905	bool containsNonAscii() const {
1906	for (auto c : getString())
1907	if (!isASCII(c))
1908	return true;
1909	return false;
1910	}
1911
1912	bool containsNonAsciiOrNull() const {
1913	for (auto c : getString())
1914	if (!isASCII(c) || !c)
1915	return true;
1916	return false;
1917	}
1918
1919	/// getNumConcatenated - Get the number of string literal tokens that were
1920	/// concatenated in translation phase #6 to form this string literal.
1921	unsigned getNumConcatenated() const {
1922	return StringLiteralBits.NumConcatenated;
1923	}
1924
1925	/// Get one of the string literal token.
1926	SourceLocation getStrTokenLoc(unsigned TokNum) const {
1927	assert(TokNum < getNumConcatenated() && "Invalid tok number");
1928	return getTrailingObjects<SourceLocation>()[TokNum];
1929	}
1930
1931	/// getLocationOfByte - Return a source location that points to the specified
1932	/// byte of this string literal.
1933	///
1934	/// Strings are amazingly complex. They can be formed from multiple tokens
1935	/// and can have escape sequences in them in addition to the usual trigraph
1936	/// and escaped newline business. This routine handles this complexity.
1937	///
1938	SourceLocation
1939	getLocationOfByte(unsigned ByteNo, const SourceManager &SM,
1940	const LangOptions &Features, const TargetInfo &Target,
1941	unsigned *StartToken = nullptr,
1942	unsigned *StartTokenByteOffset = nullptr) const;
1943
1944	typedef const SourceLocation *tokloc_iterator;
1945
1946	tokloc_iterator tokloc_begin() const {
1947	return getTrailingObjects<SourceLocation>();
1948	}
1949
1950	tokloc_iterator tokloc_end() const {
1951	return getTrailingObjects<SourceLocation>() + getNumConcatenated();
1952	}
1953
1954	SourceLocation getBeginLoc() const LLVM_READONLY { return *tokloc_begin(); }
1955	SourceLocation getEndLoc() const LLVM_READONLY { return *(tokloc_end() - 1); }
1956
1957	static bool classof(const Stmt *T) {
1958	return T->getStmtClass() == StringLiteralClass;
1959	}
1960
1961	// Iterators
1962	child_range children() {
1963	return child_range(child_iterator(), child_iterator());
1964	}
1965	const_child_range children() const {
1966	return const_child_range(const_child_iterator(), const_child_iterator());
1967	}
1968	};
1969
1970	enum class PredefinedIdentKind {
1971	Func,
1972	Function,
1973	LFunction, // Same as Function, but as wide string.
1974	FuncDName,
1975	FuncSig,
1976	LFuncSig, // Same as FuncSig, but as wide string
1977	PrettyFunction,
1978	/// The same as PrettyFunction, except that the
1979	/// 'virtual' keyword is omitted for virtual member functions.
1980	PrettyFunctionNoVirtual
1981	};
1982
1983	/// [C99 6.4.2.2] - A predefined identifier such as __func__.
1984	class PredefinedExpr final
1985	: public Expr,
1986	private llvm::TrailingObjects<PredefinedExpr, Stmt *> {
1987	friend class ASTStmtReader;
1988	friend TrailingObjects;
1989
1990	// PredefinedExpr is optionally followed by a single trailing
1991	// "Stmt *" for the predefined identifier. It is present if and only if
1992	// hasFunctionName() is true and is always a "StringLiteral *".
1993
1994	PredefinedExpr(SourceLocation L, QualType FNTy, PredefinedIdentKind IK,
1995	bool IsTransparent, StringLiteral *SL);
1996
1997	explicit PredefinedExpr(EmptyShell Empty, bool HasFunctionName);
1998
1999	/// True if this PredefinedExpr has storage for a function name.
2000	bool hasFunctionName() const { return PredefinedExprBits.HasFunctionName; }
2001
2002	void setFunctionName(StringLiteral *SL) {
2003	assert(hasFunctionName() &&
2004	"This PredefinedExpr has no storage for a function name!");
2005	*getTrailingObjects<Stmt *>() = SL;
2006	}
2007
2008	public:
2009	/// Create a PredefinedExpr.
2010	///
2011	/// If IsTransparent, the PredefinedExpr is transparently handled as a
2012	/// StringLiteral.
2013	static PredefinedExpr *Create(const ASTContext &Ctx, SourceLocation L,
2014	QualType FNTy, PredefinedIdentKind IK,
2015	bool IsTransparent, StringLiteral *SL);
2016
2017	/// Create an empty PredefinedExpr.
2018	static PredefinedExpr *CreateEmpty(const ASTContext &Ctx,
2019	bool HasFunctionName);
2020
2021	PredefinedIdentKind getIdentKind() const {
2022	return static_cast<PredefinedIdentKind>(PredefinedExprBits.Kind);
2023	}
2024
2025	bool isTransparent() const { return PredefinedExprBits.IsTransparent; }
2026
2027	SourceLocation getLocation() const { return PredefinedExprBits.Loc; }
2028	void setLocation(SourceLocation L) { PredefinedExprBits.Loc = L; }
2029
2030	StringLiteral *getFunctionName() {
2031	return hasFunctionName()
2032	? static_cast<StringLiteral *>(*getTrailingObjects<Stmt *>())
2033	: nullptr;
2034	}
2035
2036	const StringLiteral *getFunctionName() const {
2037	return hasFunctionName()
2038	? static_cast<StringLiteral *>(*getTrailingObjects<Stmt *>())
2039	: nullptr;
2040	}
2041
2042	static StringRef getIdentKindName(PredefinedIdentKind IK);
2043	StringRef getIdentKindName() const {
2044	return getIdentKindName(IK: getIdentKind());
2045	}
2046
2047	static std::string ComputeName(PredefinedIdentKind IK,
2048	const Decl *CurrentDecl,
2049	bool ForceElaboratedPrinting = false);
2050
2051	SourceLocation getBeginLoc() const { return getLocation(); }
2052	SourceLocation getEndLoc() const { return getLocation(); }
2053
2054	static bool classof(const Stmt *T) {
2055	return T->getStmtClass() == PredefinedExprClass;
2056	}
2057
2058	// Iterators
2059	child_range children() {
2060	return child_range(getTrailingObjects<Stmt *>(),
2061	getTrailingObjects<Stmt *>() + hasFunctionName());
2062	}
2063
2064	const_child_range children() const {
2065	return const_child_range(getTrailingObjects<Stmt *>(),
2066	getTrailingObjects<Stmt *>() + hasFunctionName());
2067	}
2068	};
2069
2070	// This represents a use of the __builtin_sycl_unique_stable_name, which takes a
2071	// type-id, and at CodeGen time emits a unique string representation of the
2072	// type in a way that permits us to properly encode information about the SYCL
2073	// kernels.
2074	class SYCLUniqueStableNameExpr final : public Expr {
2075	friend class ASTStmtReader;
2076	SourceLocation OpLoc, LParen, RParen;
2077	TypeSourceInfo *TypeInfo;
2078
2079	SYCLUniqueStableNameExpr(EmptyShell Empty, QualType ResultTy);
2080	SYCLUniqueStableNameExpr(SourceLocation OpLoc, SourceLocation LParen,
2081	SourceLocation RParen, QualType ResultTy,
2082	TypeSourceInfo *TSI);
2083
2084	void setTypeSourceInfo(TypeSourceInfo *Ty) { TypeInfo = Ty; }
2085
2086	void setLocation(SourceLocation L) { OpLoc = L; }
2087	void setLParenLocation(SourceLocation L) { LParen = L; }
2088	void setRParenLocation(SourceLocation L) { RParen = L; }
2089
2090	public:
2091	TypeSourceInfo *getTypeSourceInfo() { return TypeInfo; }
2092
2093	const TypeSourceInfo *getTypeSourceInfo() const { return TypeInfo; }
2094
2095	static SYCLUniqueStableNameExpr *
2096	Create(const ASTContext &Ctx, SourceLocation OpLoc, SourceLocation LParen,
2097	SourceLocation RParen, TypeSourceInfo *TSI);
2098
2099	static SYCLUniqueStableNameExpr *CreateEmpty(const ASTContext &Ctx);
2100
2101	SourceLocation getBeginLoc() const { return getLocation(); }
2102	SourceLocation getEndLoc() const { return RParen; }
2103	SourceLocation getLocation() const { return OpLoc; }
2104	SourceLocation getLParenLocation() const { return LParen; }
2105	SourceLocation getRParenLocation() const { return RParen; }
2106
2107	static bool classof(const Stmt *T) {
2108	return T->getStmtClass() == SYCLUniqueStableNameExprClass;
2109	}
2110
2111	// Iterators
2112	child_range children() {
2113	return child_range(child_iterator(), child_iterator());
2114	}
2115
2116	const_child_range children() const {
2117	return const_child_range(const_child_iterator(), const_child_iterator());
2118	}
2119
2120	// Convenience function to generate the name of the currently stored type.
2121	std::string ComputeName(ASTContext &Context) const;
2122
2123	// Get the generated name of the type. Note that this only works after all
2124	// kernels have been instantiated.
2125	static std::string ComputeName(ASTContext &Context, QualType Ty);
2126	};
2127
2128	/// ParenExpr - This represents a parethesized expression, e.g. "(1)". This
2129	/// AST node is only formed if full location information is requested.
2130	class ParenExpr : public Expr {
2131	SourceLocation L, R;
2132	Stmt *Val;
2133	public:
2134	ParenExpr(SourceLocation l, SourceLocation r, Expr *val)
2135	: Expr(ParenExprClass, val->getType(), val->getValueKind(),
2136	val->getObjectKind()),
2137	L(l), R(r), Val(val) {
2138	setDependence(computeDependence(E: this));
2139	}
2140
2141	/// Construct an empty parenthesized expression.
2142	explicit ParenExpr(EmptyShell Empty)
2143	: Expr(ParenExprClass, Empty) { }
2144
2145	const Expr *getSubExpr() const { return cast<Expr>(Val); }
2146	Expr *getSubExpr() { return cast<Expr>(Val); }
2147	void setSubExpr(Expr *E) { Val = E; }
2148
2149	SourceLocation getBeginLoc() const LLVM_READONLY { return L; }
2150	SourceLocation getEndLoc() const LLVM_READONLY { return R; }
2151
2152	/// Get the location of the left parentheses '('.
2153	SourceLocation getLParen() const { return L; }
2154	void setLParen(SourceLocation Loc) { L = Loc; }
2155
2156	/// Get the location of the right parentheses ')'.
2157	SourceLocation getRParen() const { return R; }
2158	void setRParen(SourceLocation Loc) { R = Loc; }
2159
2160	static bool classof(const Stmt *T) {
2161	return T->getStmtClass() == ParenExprClass;
2162	}
2163
2164	// Iterators
2165	child_range children() { return child_range(&Val, &Val+1); }
2166	const_child_range children() const {
2167	return const_child_range(&Val, &Val + 1);
2168	}
2169	};
2170
2171	/// UnaryOperator - This represents the unary-expression's (except sizeof and
2172	/// alignof), the postinc/postdec operators from postfix-expression, and various
2173	/// extensions.
2174	///
2175	/// Notes on various nodes:
2176	///
2177	/// Real/Imag - These return the real/imag part of a complex operand. If
2178	/// applied to a non-complex value, the former returns its operand and the
2179	/// later returns zero in the type of the operand.
2180	///
2181	class UnaryOperator final
2182	: public Expr,
2183	private llvm::TrailingObjects<UnaryOperator, FPOptionsOverride> {
2184	Stmt *Val;
2185
2186	size_t numTrailingObjects(OverloadToken<FPOptionsOverride>) const {
2187	return UnaryOperatorBits.HasFPFeatures ? 1 : 0;
2188	}
2189
2190	FPOptionsOverride &getTrailingFPFeatures() {
2191	assert(UnaryOperatorBits.HasFPFeatures);
2192	return *getTrailingObjects<FPOptionsOverride>();
2193	}
2194
2195	const FPOptionsOverride &getTrailingFPFeatures() const {
2196	assert(UnaryOperatorBits.HasFPFeatures);
2197	return *getTrailingObjects<FPOptionsOverride>();
2198	}
2199
2200	public:
2201	typedef UnaryOperatorKind Opcode;
2202
2203	protected:
2204	UnaryOperator(const ASTContext &Ctx, Expr *input, Opcode opc, QualType type,
2205	ExprValueKind VK, ExprObjectKind OK, SourceLocation l,
2206	bool CanOverflow, FPOptionsOverride FPFeatures);
2207
2208	/// Build an empty unary operator.
2209	explicit UnaryOperator(bool HasFPFeatures, EmptyShell Empty)
2210	: Expr(UnaryOperatorClass, Empty) {
2211	UnaryOperatorBits.Opc = UO_AddrOf;
2212	UnaryOperatorBits.HasFPFeatures = HasFPFeatures;
2213	}
2214
2215	public:
2216	static UnaryOperator *CreateEmpty(const ASTContext &C, bool hasFPFeatures);
2217
2218	static UnaryOperator *Create(const ASTContext &C, Expr *input, Opcode opc,
2219	QualType type, ExprValueKind VK,
2220	ExprObjectKind OK, SourceLocation l,
2221	bool CanOverflow, FPOptionsOverride FPFeatures);
2222
2223	Opcode getOpcode() const {
2224	return static_cast<Opcode>(UnaryOperatorBits.Opc);
2225	}
2226	void setOpcode(Opcode Opc) { UnaryOperatorBits.Opc = Opc; }
2227
2228	Expr *getSubExpr() const { return cast<Expr>(Val); }
2229	void setSubExpr(Expr *E) { Val = E; }
2230
2231	/// getOperatorLoc - Return the location of the operator.
2232	SourceLocation getOperatorLoc() const { return UnaryOperatorBits.Loc; }
2233	void setOperatorLoc(SourceLocation L) { UnaryOperatorBits.Loc = L; }
2234
2235	/// Returns true if the unary operator can cause an overflow. For instance,
2236	/// signed int i = INT_MAX; i++;
2237	/// signed char c = CHAR_MAX; c++;
2238	/// Due to integer promotions, c++ is promoted to an int before the postfix
2239	/// increment, and the result is an int that cannot overflow. However, i++
2240	/// can overflow.
2241	bool canOverflow() const { return UnaryOperatorBits.CanOverflow; }
2242	void setCanOverflow(bool C) { UnaryOperatorBits.CanOverflow = C; }
2243
2244	/// Get the FP contractability status of this operator. Only meaningful for
2245	/// operations on floating point types.
2246	bool isFPContractableWithinStatement(const LangOptions &LO) const {
2247	return getFPFeaturesInEffect(LO).allowFPContractWithinStatement();
2248	}
2249
2250	/// Get the FENV_ACCESS status of this operator. Only meaningful for
2251	/// operations on floating point types.
2252	bool isFEnvAccessOn(const LangOptions &LO) const {
2253	return getFPFeaturesInEffect(LO).getAllowFEnvAccess();
2254	}
2255
2256	/// isPostfix - Return true if this is a postfix operation, like x++.
2257	static bool isPostfix(Opcode Op) {
2258	return Op == UO_PostInc || Op == UO_PostDec;
2259	}
2260
2261	/// isPrefix - Return true if this is a prefix operation, like --x.
2262	static bool isPrefix(Opcode Op) {
2263	return Op == UO_PreInc || Op == UO_PreDec;
2264	}
2265
2266	bool isPrefix() const { return isPrefix(Op: getOpcode()); }
2267	bool isPostfix() const { return isPostfix(Op: getOpcode()); }
2268
2269	static bool isIncrementOp(Opcode Op) {
2270	return Op == UO_PreInc || Op == UO_PostInc;
2271	}
2272	bool isIncrementOp() const {
2273	return isIncrementOp(Op: getOpcode());
2274	}
2275
2276	static bool isDecrementOp(Opcode Op) {
2277	return Op == UO_PreDec || Op == UO_PostDec;
2278	}
2279	bool isDecrementOp() const {
2280	return isDecrementOp(Op: getOpcode());
2281	}
2282
2283	static bool isIncrementDecrementOp(Opcode Op) { return Op <= UO_PreDec; }
2284	bool isIncrementDecrementOp() const {
2285	return isIncrementDecrementOp(Op: getOpcode());
2286	}
2287
2288	static bool isArithmeticOp(Opcode Op) {
2289	return Op >= UO_Plus && Op <= UO_LNot;
2290	}
2291	bool isArithmeticOp() const { return isArithmeticOp(Op: getOpcode()); }
2292
2293	/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it
2294	/// corresponds to, e.g. "sizeof" or "[pre]++"
2295	static StringRef getOpcodeStr(Opcode Op);
2296
2297	/// Retrieve the unary opcode that corresponds to the given
2298	/// overloaded operator.
2299	static Opcode getOverloadedOpcode(OverloadedOperatorKind OO, bool Postfix);
2300
2301	/// Retrieve the overloaded operator kind that corresponds to
2302	/// the given unary opcode.
2303	static OverloadedOperatorKind getOverloadedOperator(Opcode Opc);
2304
2305	SourceLocation getBeginLoc() const LLVM_READONLY {
2306	return isPostfix() ? Val->getBeginLoc() : getOperatorLoc();
2307	}
2308	SourceLocation getEndLoc() const LLVM_READONLY {
2309	return isPostfix() ? getOperatorLoc() : Val->getEndLoc();
2310	}
2311	SourceLocation getExprLoc() const { return getOperatorLoc(); }
2312
2313	static bool classof(const Stmt *T) {
2314	return T->getStmtClass() == UnaryOperatorClass;
2315	}
2316
2317	// Iterators
2318	child_range children() { return child_range(&Val, &Val+1); }
2319	const_child_range children() const {
2320	return const_child_range(&Val, &Val + 1);
2321	}
2322
2323	/// Is FPFeatures in Trailing Storage?
2324	bool hasStoredFPFeatures() const { return UnaryOperatorBits.HasFPFeatures; }
2325
2326	/// Get FPFeatures from trailing storage.
2327	FPOptionsOverride getStoredFPFeatures() const {
2328	return getTrailingFPFeatures();
2329	}
2330
2331	protected:
2332	/// Set FPFeatures in trailing storage, used by Serialization & ASTImporter.
2333	void setStoredFPFeatures(FPOptionsOverride F) { getTrailingFPFeatures() = F; }
2334
2335	public:
2336	/// Get the FP features status of this operator. Only meaningful for
2337	/// operations on floating point types.
2338	FPOptions getFPFeaturesInEffect(const LangOptions &LO) const {
2339	if (UnaryOperatorBits.HasFPFeatures)
2340	return getStoredFPFeatures().applyOverrides(LO);
2341	return FPOptions::defaultWithoutTrailingStorage(LO);
2342	}
2343	FPOptionsOverride getFPOptionsOverride() const {
2344	if (UnaryOperatorBits.HasFPFeatures)
2345	return getStoredFPFeatures();
2346	return FPOptionsOverride();
2347	}
2348
2349	friend TrailingObjects;
2350	friend class ASTNodeImporter;
2351	friend class ASTReader;
2352	friend class ASTStmtReader;
2353	friend class ASTStmtWriter;
2354	};
2355
2356	/// Helper class for OffsetOfExpr.
2357
2358	// __builtin_offsetof(type, identifier(.identifier|[expr])*)
2359	class OffsetOfNode {
2360	public:
2361	/// The kind of offsetof node we have.
2362	enum Kind {
2363	/// An index into an array.
2364	Array = 0x00,
2365	/// A field.
2366	Field = 0x01,
2367	/// A field in a dependent type, known only by its name.
2368	Identifier = 0x02,
2369	/// An implicit indirection through a C++ base class, when the
2370	/// field found is in a base class.
2371	Base = 0x03
2372	};
2373
2374	private:
2375	enum { MaskBits = 2, Mask = 0x03 };
2376
2377	/// The source range that covers this part of the designator.
2378	SourceRange Range;
2379
2380	/// The data describing the designator, which comes in three
2381	/// different forms, depending on the lower two bits.
2382	/// - An unsigned index into the array of Expr*'s stored after this node
2383	/// in memory, for [constant-expression] designators.
2384	/// - A FieldDecl*, for references to a known field.
2385	/// - An IdentifierInfo*, for references to a field with a given name
2386	/// when the class type is dependent.
2387	/// - A CXXBaseSpecifier*, for references that look at a field in a
2388	/// base class.
2389	uintptr_t Data;
2390
2391	public:
2392	/// Create an offsetof node that refers to an array element.
2393	OffsetOfNode(SourceLocation LBracketLoc, unsigned Index,
2394	SourceLocation RBracketLoc)
2395	: Range(LBracketLoc, RBracketLoc), Data((Index << 2) | Array) {}
2396
2397	/// Create an offsetof node that refers to a field.
2398	OffsetOfNode(SourceLocation DotLoc, FieldDecl *Field, SourceLocation NameLoc)
2399	: Range(DotLoc.isValid() ? DotLoc : NameLoc, NameLoc),
2400	Data(reinterpret_cast<uintptr_t>(Field) | OffsetOfNode::Field) {}
2401
2402	/// Create an offsetof node that refers to an identifier.
2403	OffsetOfNode(SourceLocation DotLoc, IdentifierInfo *Name,
2404	SourceLocation NameLoc)
2405	: Range(DotLoc.isValid() ? DotLoc : NameLoc, NameLoc),
2406	Data(reinterpret_cast<uintptr_t>(Name) | Identifier) {}
2407
2408	/// Create an offsetof node that refers into a C++ base class.
2409	explicit OffsetOfNode(const CXXBaseSpecifier *Base)
2410	: Data(reinterpret_cast<uintptr_t>(Base) | OffsetOfNode::Base) {}
2411
2412	/// Determine what kind of offsetof node this is.
2413	Kind getKind() const { return static_cast<Kind>(Data & Mask); }
2414
2415	/// For an array element node, returns the index into the array
2416	/// of expressions.
2417	unsigned getArrayExprIndex() const {
2418	assert(getKind() == Array);
2419	return Data >> 2;
2420	}
2421
2422	/// For a field offsetof node, returns the field.
2423	FieldDecl *getField() const {
2424	assert(getKind() == Field);
2425	return reinterpret_cast<FieldDecl *>(Data & ~(uintptr_t)Mask);
2426	}
2427
2428	/// For a field or identifier offsetof node, returns the name of
2429	/// the field.
2430	IdentifierInfo *getFieldName() const;
2431
2432	/// For a base class node, returns the base specifier.
2433	CXXBaseSpecifier *getBase() const {
2434	assert(getKind() == Base);
2435	return reinterpret_cast<CXXBaseSpecifier *>(Data & ~(uintptr_t)Mask);
2436	}
2437
2438	/// Retrieve the source range that covers this offsetof node.
2439	///
2440	/// For an array element node, the source range contains the locations of
2441	/// the square brackets. For a field or identifier node, the source range
2442	/// contains the location of the period (if there is one) and the
2443	/// identifier.
2444	SourceRange getSourceRange() const LLVM_READONLY { return Range; }
2445	SourceLocation getBeginLoc() const LLVM_READONLY { return Range.getBegin(); }
2446	SourceLocation getEndLoc() const LLVM_READONLY { return Range.getEnd(); }
2447	};
2448
2449	/// OffsetOfExpr - [C99 7.17] - This represents an expression of the form
2450	/// offsetof(record-type, member-designator). For example, given:
2451	/// @code
2452	/// struct S {
2453	/// float f;
2454	/// double d;
2455	/// };
2456	/// struct T {
2457	/// int i;
2458	/// struct S s[10];
2459	/// };
2460	/// @endcode
2461	/// we can represent and evaluate the expression @c offsetof(struct T, s[2].d).
2462
2463	class OffsetOfExpr final
2464	: public Expr,
2465	private llvm::TrailingObjects<OffsetOfExpr, OffsetOfNode, Expr *> {
2466	SourceLocation OperatorLoc, RParenLoc;
2467	// Base type;
2468	TypeSourceInfo *TSInfo;
2469	// Number of sub-components (i.e. instances of OffsetOfNode).
2470	unsigned NumComps;
2471	// Number of sub-expressions (i.e. array subscript expressions).
2472	unsigned NumExprs;
2473
2474	size_t numTrailingObjects(OverloadToken<OffsetOfNode>) const {
2475	return NumComps;
2476	}
2477
2478	OffsetOfExpr(const ASTContext &C, QualType type,
2479	SourceLocation OperatorLoc, TypeSourceInfo *tsi,
2480	ArrayRef<OffsetOfNode> comps, ArrayRef<Expr*> exprs,
2481	SourceLocation RParenLoc);
2482
2483	explicit OffsetOfExpr(unsigned numComps, unsigned numExprs)
2484	: Expr(OffsetOfExprClass, EmptyShell()),
2485	TSInfo(nullptr), NumComps(numComps), NumExprs(numExprs) {}
2486
2487	public:
2488
2489	static OffsetOfExpr *Create(const ASTContext &C, QualType type,
2490	SourceLocation OperatorLoc, TypeSourceInfo *tsi,
2491	ArrayRef<OffsetOfNode> comps,
2492	ArrayRef<Expr*> exprs, SourceLocation RParenLoc);
2493
2494	static OffsetOfExpr *CreateEmpty(const ASTContext &C,
2495	unsigned NumComps, unsigned NumExprs);
2496
2497	/// getOperatorLoc - Return the location of the operator.
2498	SourceLocation getOperatorLoc() const { return OperatorLoc; }
2499	void setOperatorLoc(SourceLocation L) { OperatorLoc = L; }
2500
2501	/// Return the location of the right parentheses.
2502	SourceLocation getRParenLoc() const { return RParenLoc; }
2503	void setRParenLoc(SourceLocation R) { RParenLoc = R; }
2504
2505	TypeSourceInfo *getTypeSourceInfo() const {
2506	return TSInfo;
2507	}
2508	void setTypeSourceInfo(TypeSourceInfo *tsi) {
2509	TSInfo = tsi;
2510	}
2511
2512	const OffsetOfNode &getComponent(unsigned Idx) const {
2513	assert(Idx < NumComps && "Subscript out of range");
2514	return getTrailingObjects<OffsetOfNode>()[Idx];
2515	}
2516
2517	void setComponent(unsigned Idx, OffsetOfNode ON) {
2518	assert(Idx < NumComps && "Subscript out of range");
2519	getTrailingObjects<OffsetOfNode>()[Idx] = ON;
2520	}
2521
2522	unsigned getNumComponents() const {
2523	return NumComps;
2524	}
2525
2526	Expr* getIndexExpr(unsigned Idx) {
2527	assert(Idx < NumExprs && "Subscript out of range");
2528	return getTrailingObjects<Expr *>()[Idx];
2529	}
2530
2531	const Expr *getIndexExpr(unsigned Idx) const {
2532	assert(Idx < NumExprs && "Subscript out of range");
2533	return getTrailingObjects<Expr *>()[Idx];
2534	}
2535
2536	void setIndexExpr(unsigned Idx, Expr* E) {
2537	assert(Idx < NumComps && "Subscript out of range");
2538	getTrailingObjects<Expr *>()[Idx] = E;
2539	}
2540
2541	unsigned getNumExpressions() const {
2542	return NumExprs;
2543	}
2544
2545	SourceLocation getBeginLoc() const LLVM_READONLY { return OperatorLoc; }
2546	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
2547
2548	static bool classof(const Stmt *T) {
2549	return T->getStmtClass() == OffsetOfExprClass;
2550	}
2551
2552	// Iterators
2553	child_range children() {
2554	Stmt **begin = reinterpret_cast<Stmt **>(getTrailingObjects<Expr *>());
2555	return child_range(begin, begin + NumExprs);
2556	}
2557	const_child_range children() const {
2558	Stmt *const *begin =
2559	reinterpret_cast<Stmt *const *>(getTrailingObjects<Expr *>());
2560	return const_child_range(begin, begin + NumExprs);
2561	}
2562	friend TrailingObjects;
2563	};
2564
2565	/// UnaryExprOrTypeTraitExpr - expression with either a type or (unevaluated)
2566	/// expression operand. Used for sizeof/alignof (C99 6.5.3.4) and
2567	/// vec_step (OpenCL 1.1 6.11.12).
2568	class UnaryExprOrTypeTraitExpr : public Expr {
2569	union {
2570	TypeSourceInfo *Ty;
2571	Stmt *Ex;
2572	} Argument;
2573	SourceLocation OpLoc, RParenLoc;
2574
2575	public:
2576	UnaryExprOrTypeTraitExpr(UnaryExprOrTypeTrait ExprKind, TypeSourceInfo *TInfo,
2577	QualType resultType, SourceLocation op,
2578	SourceLocation rp)
2579	: Expr(UnaryExprOrTypeTraitExprClass, resultType, VK_PRValue,
2580	OK_Ordinary),
2581	OpLoc(op), RParenLoc(rp) {
2582	assert(ExprKind <= UETT_Last && "invalid enum value!");
2583	UnaryExprOrTypeTraitExprBits.Kind = ExprKind;
2584	assert(static_cast<unsigned>(ExprKind) ==
2585	UnaryExprOrTypeTraitExprBits.Kind &&
2586	"UnaryExprOrTypeTraitExprBits.Kind overflow!");
2587	UnaryExprOrTypeTraitExprBits.IsType = true;
2588	Argument.Ty = TInfo;
2589	setDependence(computeDependence(E: this));
2590	}
2591
2592	UnaryExprOrTypeTraitExpr(UnaryExprOrTypeTrait ExprKind, Expr *E,
2593	QualType resultType, SourceLocation op,
2594	SourceLocation rp);
2595
2596	/// Construct an empty sizeof/alignof expression.
2597	explicit UnaryExprOrTypeTraitExpr(EmptyShell Empty)
2598	: Expr(UnaryExprOrTypeTraitExprClass, Empty) { }
2599
2600	UnaryExprOrTypeTrait getKind() const {
2601	return static_cast<UnaryExprOrTypeTrait>(UnaryExprOrTypeTraitExprBits.Kind);
2602	}
2603	void setKind(UnaryExprOrTypeTrait K) {
2604	assert(K <= UETT_Last && "invalid enum value!");
2605	UnaryExprOrTypeTraitExprBits.Kind = K;
2606	assert(static_cast<unsigned>(K) == UnaryExprOrTypeTraitExprBits.Kind &&
2607	"UnaryExprOrTypeTraitExprBits.Kind overflow!");
2608	}
2609
2610	bool isArgumentType() const { return UnaryExprOrTypeTraitExprBits.IsType; }
2611	QualType getArgumentType() const {
2612	return getArgumentTypeInfo()->getType();
2613	}
2614	TypeSourceInfo *getArgumentTypeInfo() const {
2615	assert(isArgumentType() && "calling getArgumentType() when arg is expr");
2616	return Argument.Ty;
2617	}
2618	Expr *getArgumentExpr() {
2619	assert(!isArgumentType() && "calling getArgumentExpr() when arg is type");
2620	return static_cast<Expr*>(Argument.Ex);
2621	}
2622	const Expr *getArgumentExpr() const {
2623	return const_cast<UnaryExprOrTypeTraitExpr*>(this)->getArgumentExpr();
2624	}
2625
2626	void setArgument(Expr *E) {
2627	Argument.Ex = E;
2628	UnaryExprOrTypeTraitExprBits.IsType = false;
2629	}
2630	void setArgument(TypeSourceInfo *TInfo) {
2631	Argument.Ty = TInfo;
2632	UnaryExprOrTypeTraitExprBits.IsType = true;
2633	}
2634
2635	/// Gets the argument type, or the type of the argument expression, whichever
2636	/// is appropriate.
2637	QualType getTypeOfArgument() const {
2638	return isArgumentType() ? getArgumentType() : getArgumentExpr()->getType();
2639	}
2640
2641	SourceLocation getOperatorLoc() const { return OpLoc; }
2642	void setOperatorLoc(SourceLocation L) { OpLoc = L; }
2643
2644	SourceLocation getRParenLoc() const { return RParenLoc; }
2645	void setRParenLoc(SourceLocation L) { RParenLoc = L; }
2646
2647	SourceLocation getBeginLoc() const LLVM_READONLY { return OpLoc; }
2648	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
2649
2650	static bool classof(const Stmt *T) {
2651	return T->getStmtClass() == UnaryExprOrTypeTraitExprClass;
2652	}
2653
2654	// Iterators
2655	child_range children();
2656	const_child_range children() const;
2657	};
2658
2659	//===----------------------------------------------------------------------===//
2660	// Postfix Operators.
2661	//===----------------------------------------------------------------------===//
2662
2663	/// ArraySubscriptExpr - [C99 6.5.2.1] Array Subscripting.
2664	class ArraySubscriptExpr : public Expr {
2665	enum { LHS, RHS, END_EXPR };
2666	Stmt *SubExprs[END_EXPR];
2667
2668	bool lhsIsBase() const { return getRHS()->getType()->isIntegerType(); }
2669
2670	public:
2671	ArraySubscriptExpr(Expr *lhs, Expr *rhs, QualType t, ExprValueKind VK,
2672	ExprObjectKind OK, SourceLocation rbracketloc)
2673	: Expr(ArraySubscriptExprClass, t, VK, OK) {
2674	SubExprs[LHS] = lhs;
2675	SubExprs[RHS] = rhs;
2676	ArrayOrMatrixSubscriptExprBits.RBracketLoc = rbracketloc;
2677	setDependence(computeDependence(E: this));
2678	}
2679
2680	/// Create an empty array subscript expression.
2681	explicit ArraySubscriptExpr(EmptyShell Shell)
2682	: Expr(ArraySubscriptExprClass, Shell) { }
2683
2684	/// An array access can be written A[4] or 4[A] (both are equivalent).
2685	/// - getBase() and getIdx() always present the normalized view: A[4].
2686	/// In this case getBase() returns "A" and getIdx() returns "4".
2687	/// - getLHS() and getRHS() present the syntactic view. e.g. for
2688	/// 4[A] getLHS() returns "4".
2689	/// Note: Because vector element access is also written A[4] we must
2690	/// predicate the format conversion in getBase and getIdx only on the
2691	/// the type of the RHS, as it is possible for the LHS to be a vector of
2692	/// integer type
2693	Expr *getLHS() { return cast<Expr>(Val: SubExprs[LHS]); }
2694	const Expr *getLHS() const { return cast<Expr>(Val: SubExprs[LHS]); }
2695	void setLHS(Expr *E) { SubExprs[LHS] = E; }
2696
2697	Expr *getRHS() { return cast<Expr>(Val: SubExprs[RHS]); }
2698	const Expr *getRHS() const { return cast<Expr>(Val: SubExprs[RHS]); }
2699	void setRHS(Expr *E) { SubExprs[RHS] = E; }
2700
2701	Expr *getBase() { return lhsIsBase() ? getLHS() : getRHS(); }
2702	const Expr *getBase() const { return lhsIsBase() ? getLHS() : getRHS(); }
2703
2704	Expr *getIdx() { return lhsIsBase() ? getRHS() : getLHS(); }
2705	const Expr *getIdx() const { return lhsIsBase() ? getRHS() : getLHS(); }
2706
2707	SourceLocation getBeginLoc() const LLVM_READONLY {
2708	return getLHS()->getBeginLoc();
2709	}
2710	SourceLocation getEndLoc() const { return getRBracketLoc(); }
2711
2712	SourceLocation getRBracketLoc() const {
2713	return ArrayOrMatrixSubscriptExprBits.RBracketLoc;
2714	}
2715	void setRBracketLoc(SourceLocation L) {
2716	ArrayOrMatrixSubscriptExprBits.RBracketLoc = L;
2717	}
2718
2719	SourceLocation getExprLoc() const LLVM_READONLY {
2720	return getBase()->getExprLoc();
2721	}
2722
2723	static bool classof(const Stmt *T) {
2724	return T->getStmtClass() == ArraySubscriptExprClass;
2725	}
2726
2727	// Iterators
2728	child_range children() {
2729	return child_range(&SubExprs[0], &SubExprs[0]+END_EXPR);
2730	}
2731	const_child_range children() const {
2732	return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
2733	}
2734	};
2735
2736	/// MatrixSubscriptExpr - Matrix subscript expression for the MatrixType
2737	/// extension.
2738	/// MatrixSubscriptExpr can be either incomplete (only Base and RowIdx are set
2739	/// so far, the type is IncompleteMatrixIdx) or complete (Base, RowIdx and
2740	/// ColumnIdx refer to valid expressions). Incomplete matrix expressions only
2741	/// exist during the initial construction of the AST.
2742	class MatrixSubscriptExpr : public Expr {
2743	enum { BASE, ROW_IDX, COLUMN_IDX, END_EXPR };
2744	Stmt *SubExprs[END_EXPR];
2745
2746	public:
2747	MatrixSubscriptExpr(Expr *Base, Expr *RowIdx, Expr *ColumnIdx, QualType T,
2748	SourceLocation RBracketLoc)
2749	: Expr(MatrixSubscriptExprClass, T, Base->getValueKind(),
2750	OK_MatrixComponent) {
2751	SubExprs[BASE] = Base;
2752	SubExprs[ROW_IDX] = RowIdx;
2753	SubExprs[COLUMN_IDX] = ColumnIdx;
2754	ArrayOrMatrixSubscriptExprBits.RBracketLoc = RBracketLoc;
2755	setDependence(computeDependence(E: this));
2756	}
2757
2758	/// Create an empty matrix subscript expression.
2759	explicit MatrixSubscriptExpr(EmptyShell Shell)
2760	: Expr(MatrixSubscriptExprClass, Shell) {}
2761
2762	bool isIncomplete() const {
2763	bool IsIncomplete = hasPlaceholderType(BuiltinType::IncompleteMatrixIdx);
2764	assert((SubExprs[COLUMN_IDX] || IsIncomplete) &&
2765	"expressions without column index must be marked as incomplete");
2766	return IsIncomplete;
2767	}
2768	Expr *getBase() { return cast<Expr>(Val: SubExprs[BASE]); }
2769	const Expr *getBase() const { return cast<Expr>(Val: SubExprs[BASE]); }
2770	void setBase(Expr *E) { SubExprs[BASE] = E; }
2771
2772	Expr *getRowIdx() { return cast<Expr>(Val: SubExprs[ROW_IDX]); }
2773	const Expr *getRowIdx() const { return cast<Expr>(Val: SubExprs[ROW_IDX]); }
2774	void setRowIdx(Expr *E) { SubExprs[ROW_IDX] = E; }
2775
2776	Expr *getColumnIdx() { return cast_or_null<Expr>(Val: SubExprs[COLUMN_IDX]); }
2777	const Expr *getColumnIdx() const {
2778	assert(!isIncomplete() &&
2779	"cannot get the column index of an incomplete expression");
2780	return cast<Expr>(Val: SubExprs[COLUMN_IDX]);
2781	}
2782	void setColumnIdx(Expr *E) { SubExprs[COLUMN_IDX] = E; }
2783
2784	SourceLocation getBeginLoc() const LLVM_READONLY {
2785	return getBase()->getBeginLoc();
2786	}
2787
2788	SourceLocation getEndLoc() const { return getRBracketLoc(); }
2789
2790	SourceLocation getExprLoc() const LLVM_READONLY {
2791	return getBase()->getExprLoc();
2792	}
2793
2794	SourceLocation getRBracketLoc() const {
2795	return ArrayOrMatrixSubscriptExprBits.RBracketLoc;
2796	}
2797	void setRBracketLoc(SourceLocation L) {
2798	ArrayOrMatrixSubscriptExprBits.RBracketLoc = L;
2799	}
2800
2801	static bool classof(const Stmt *T) {
2802	return T->getStmtClass() == MatrixSubscriptExprClass;
2803	}
2804
2805	// Iterators
2806	child_range children() {
2807	return child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
2808	}
2809	const_child_range children() const {
2810	return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
2811	}
2812	};
2813
2814	/// CallExpr - Represents a function call (C99 6.5.2.2, C++ [expr.call]).
2815	/// CallExpr itself represents a normal function call, e.g., "f(x, 2)",
2816	/// while its subclasses may represent alternative syntax that (semantically)
2817	/// results in a function call. For example, CXXOperatorCallExpr is
2818	/// a subclass for overloaded operator calls that use operator syntax, e.g.,
2819	/// "str1 + str2" to resolve to a function call.
2820	class CallExpr : public Expr {
2821	enum { FN = 0, PREARGS_START = 1 };
2822
2823	/// The number of arguments in the call expression.
2824	unsigned NumArgs;
2825
2826	/// The location of the right parentheses. This has a different meaning for
2827	/// the derived classes of CallExpr.
2828	SourceLocation RParenLoc;
2829
2830	// CallExpr store some data in trailing objects. However since CallExpr
2831	// is used a base of other expression classes we cannot use
2832	// llvm::TrailingObjects. Instead we manually perform the pointer arithmetic
2833	// and casts.
2834	//
2835	// The trailing objects are in order:
2836	//
2837	// * A single "Stmt *" for the callee expression.
2838	//
2839	// * An array of getNumPreArgs() "Stmt *" for the pre-argument expressions.
2840	//
2841	// * An array of getNumArgs() "Stmt *" for the argument expressions.
2842	//
2843	// * An optional of type FPOptionsOverride.
2844	//
2845	// Note that we store the offset in bytes from the this pointer to the start
2846	// of the trailing objects. It would be perfectly possible to compute it
2847	// based on the dynamic kind of the CallExpr. However 1.) we have plenty of
2848	// space in the bit-fields of Stmt. 2.) It was benchmarked to be faster to
2849	// compute this once and then load the offset from the bit-fields of Stmt,
2850	// instead of re-computing the offset each time the trailing objects are
2851	// accessed.
2852
2853	/// Return a pointer to the start of the trailing array of "Stmt *".
2854	Stmt **getTrailingStmts() {
2855	return reinterpret_cast<Stmt **>(reinterpret_cast<char *>(this) +
2856	CallExprBits.OffsetToTrailingObjects);
2857	}
2858	Stmt *const *getTrailingStmts() const {
2859	return const_cast<CallExpr *>(this)->getTrailingStmts();
2860	}
2861
2862	/// Map a statement class to the appropriate offset in bytes from the
2863	/// this pointer to the trailing objects.
2864	static unsigned offsetToTrailingObjects(StmtClass SC);
2865
2866	unsigned getSizeOfTrailingStmts() const {
2867	return (1 + getNumPreArgs() + getNumArgs()) * sizeof(Stmt *);
2868	}
2869
2870	size_t getOffsetOfTrailingFPFeatures() const {
2871	assert(hasStoredFPFeatures());
2872	return CallExprBits.OffsetToTrailingObjects + getSizeOfTrailingStmts();
2873	}
2874
2875	public:
2876	enum class ADLCallKind : bool { NotADL, UsesADL };
2877	static constexpr ADLCallKind NotADL = ADLCallKind::NotADL;
2878	static constexpr ADLCallKind UsesADL = ADLCallKind::UsesADL;
2879
2880	protected:
2881	/// Build a call expression, assuming that appropriate storage has been
2882	/// allocated for the trailing objects.
2883	CallExpr(StmtClass SC, Expr *Fn, ArrayRef<Expr *> PreArgs,
2884	ArrayRef<Expr *> Args, QualType Ty, ExprValueKind VK,
2885	SourceLocation RParenLoc, FPOptionsOverride FPFeatures,
2886	unsigned MinNumArgs, ADLCallKind UsesADL);
2887
2888	/// Build an empty call expression, for deserialization.
2889	CallExpr(StmtClass SC, unsigned NumPreArgs, unsigned NumArgs,
2890	bool hasFPFeatures, EmptyShell Empty);
2891
2892	/// Return the size in bytes needed for the trailing objects.
2893	/// Used by the derived classes to allocate the right amount of storage.
2894	static unsigned sizeOfTrailingObjects(unsigned NumPreArgs, unsigned NumArgs,
2895	bool HasFPFeatures) {
2896	return (1 + NumPreArgs + NumArgs) * sizeof(Stmt *) +
2897	HasFPFeatures * sizeof(FPOptionsOverride);
2898	}
2899
2900	Stmt *getPreArg(unsigned I) {
2901	assert(I < getNumPreArgs() && "Prearg access out of range!");
2902	return getTrailingStmts()[PREARGS_START + I];
2903	}
2904	const Stmt *getPreArg(unsigned I) const {
2905	assert(I < getNumPreArgs() && "Prearg access out of range!");
2906	return getTrailingStmts()[PREARGS_START + I];
2907	}
2908	void setPreArg(unsigned I, Stmt *PreArg) {
2909	assert(I < getNumPreArgs() && "Prearg access out of range!");
2910	getTrailingStmts()[PREARGS_START + I] = PreArg;
2911	}
2912
2913	unsigned getNumPreArgs() const { return CallExprBits.NumPreArgs; }
2914
2915	/// Return a pointer to the trailing FPOptions
2916	FPOptionsOverride *getTrailingFPFeatures() {
2917	assert(hasStoredFPFeatures());
2918	return reinterpret_cast<FPOptionsOverride *>(
2919	reinterpret_cast<char *>(this) + CallExprBits.OffsetToTrailingObjects +
2920	getSizeOfTrailingStmts());
2921	}
2922	const FPOptionsOverride *getTrailingFPFeatures() const {
2923	assert(hasStoredFPFeatures());
2924	return reinterpret_cast<const FPOptionsOverride *>(
2925	reinterpret_cast<const char *>(this) +
2926	CallExprBits.OffsetToTrailingObjects + getSizeOfTrailingStmts());
2927	}
2928
2929	public:
2930	/// Create a call expression.
2931	/// \param Fn The callee expression,
2932	/// \param Args The argument array,
2933	/// \param Ty The type of the call expression (which is *not* the return
2934	/// type in general),
2935	/// \param VK The value kind of the call expression (lvalue, rvalue, ...),
2936	/// \param RParenLoc The location of the right parenthesis in the call
2937	/// expression.
2938	/// \param FPFeatures Floating-point features associated with the call,
2939	/// \param MinNumArgs Specifies the minimum number of arguments. The actual
2940	/// number of arguments will be the greater of Args.size()
2941	/// and MinNumArgs. This is used in a few places to allocate
2942	/// enough storage for the default arguments.
2943	/// \param UsesADL Specifies whether the callee was found through
2944	/// argument-dependent lookup.
2945	///
2946	/// Note that you can use CreateTemporary if you need a temporary call
2947	/// expression on the stack.
2948	static CallExpr *Create(const ASTContext &Ctx, Expr *Fn,
2949	ArrayRef<Expr *> Args, QualType Ty, ExprValueKind VK,
2950	SourceLocation RParenLoc,
2951	FPOptionsOverride FPFeatures, unsigned MinNumArgs = 0,
2952	ADLCallKind UsesADL = NotADL);
2953
2954	/// Create a temporary call expression with no arguments in the memory
2955	/// pointed to by Mem. Mem must points to at least sizeof(CallExpr)
2956	/// + sizeof(Stmt *) bytes of storage, aligned to alignof(CallExpr):
2957	///
2958	/// \code{.cpp}
2959	/// alignas(CallExpr) char Buffer[sizeof(CallExpr) + sizeof(Stmt *)];
2960	/// CallExpr *TheCall = CallExpr::CreateTemporary(Buffer, etc);
2961	/// \endcode
2962	static CallExpr *CreateTemporary(void *Mem, Expr *Fn, QualType Ty,
2963	ExprValueKind VK, SourceLocation RParenLoc,
2964	ADLCallKind UsesADL = NotADL);
2965
2966	/// Create an empty call expression, for deserialization.
2967	static CallExpr *CreateEmpty(const ASTContext &Ctx, unsigned NumArgs,
2968	bool HasFPFeatures, EmptyShell Empty);
2969
2970	Expr *getCallee() { return cast<Expr>(Val: getTrailingStmts()[FN]); }
2971	const Expr *getCallee() const { return cast<Expr>(Val: getTrailingStmts()[FN]); }
2972	void setCallee(Expr *F) { getTrailingStmts()[FN] = F; }
2973
2974	ADLCallKind getADLCallKind() const {
2975	return static_cast<ADLCallKind>(CallExprBits.UsesADL);
2976	}
2977	void setADLCallKind(ADLCallKind V = UsesADL) {
2978	CallExprBits.UsesADL = static_cast<bool>(V);
2979	}
2980	bool usesADL() const { return getADLCallKind() == UsesADL; }
2981
2982	bool hasStoredFPFeatures() const { return CallExprBits.HasFPFeatures; }
2983
2984	Decl *getCalleeDecl() { return getCallee()->getReferencedDeclOfCallee(); }
2985	const Decl *getCalleeDecl() const {
2986	return getCallee()->getReferencedDeclOfCallee();
2987	}
2988
2989	/// If the callee is a FunctionDecl, return it. Otherwise return null.
2990	FunctionDecl *getDirectCallee() {
2991	return dyn_cast_or_null<FunctionDecl>(Val: getCalleeDecl());
2992	}
2993	const FunctionDecl *getDirectCallee() const {
2994	return dyn_cast_or_null<FunctionDecl>(Val: getCalleeDecl());
2995	}
2996
2997	/// getNumArgs - Return the number of actual arguments to this call.
2998	unsigned getNumArgs() const { return NumArgs; }
2999
3000	/// Retrieve the call arguments.
3001	Expr **getArgs() {
3002	return reinterpret_cast<Expr **>(getTrailingStmts() + PREARGS_START +
3003	getNumPreArgs());
3004	}
3005	const Expr *const *getArgs() const {
3006	return reinterpret_cast<const Expr *const *>(
3007	getTrailingStmts() + PREARGS_START + getNumPreArgs());
3008	}
3009
3010	/// getArg - Return the specified argument.
3011	Expr *getArg(unsigned Arg) {
3012	assert(Arg < getNumArgs() && "Arg access out of range!");
3013	return getArgs()[Arg];
3014	}
3015	const Expr *getArg(unsigned Arg) const {
3016	assert(Arg < getNumArgs() && "Arg access out of range!");
3017	return getArgs()[Arg];
3018	}
3019
3020	/// setArg - Set the specified argument.
3021	/// ! the dependence bits might be stale after calling this setter, it is
3022	/// *caller*'s responsibility to recompute them by calling
3023	/// computeDependence().
3024	void setArg(unsigned Arg, Expr *ArgExpr) {
3025	assert(Arg < getNumArgs() && "Arg access out of range!");
3026	getArgs()[Arg] = ArgExpr;
3027	}
3028
3029	/// Compute and set dependence bits.
3030	void computeDependence() {
3031	setDependence(clang::computeDependence(
3032	E: this, PreArgs: llvm::ArrayRef(
3033	reinterpret_cast<Expr **>(getTrailingStmts() + PREARGS_START),
3034	getNumPreArgs())));
3035	}
3036
3037	/// Reduce the number of arguments in this call expression. This is used for
3038	/// example during error recovery to drop extra arguments. There is no way
3039	/// to perform the opposite because: 1.) We don't track how much storage
3040	/// we have for the argument array 2.) This would potentially require growing
3041	/// the argument array, something we cannot support since the arguments are
3042	/// stored in a trailing array.
3043	void shrinkNumArgs(unsigned NewNumArgs) {
3044	assert((NewNumArgs <= getNumArgs()) &&
3045	"shrinkNumArgs cannot increase the number of arguments!");
3046	NumArgs = NewNumArgs;
3047	}
3048
3049	/// Bluntly set a new number of arguments without doing any checks whatsoever.
3050	/// Only used during construction of a CallExpr in a few places in Sema.
3051	/// FIXME: Find a way to remove it.
3052	void setNumArgsUnsafe(unsigned NewNumArgs) { NumArgs = NewNumArgs; }
3053
3054	typedef ExprIterator arg_iterator;
3055	typedef ConstExprIterator const_arg_iterator;
3056	typedef llvm::iterator_range<arg_iterator> arg_range;
3057	typedef llvm::iterator_range<const_arg_iterator> const_arg_range;
3058
3059	arg_range arguments() { return arg_range(arg_begin(), arg_end()); }
3060	const_arg_range arguments() const {
3061	return const_arg_range(arg_begin(), arg_end());
3062	}
3063
3064	arg_iterator arg_begin() {
3065	return getTrailingStmts() + PREARGS_START + getNumPreArgs();
3066	}
3067	arg_iterator arg_end() { return arg_begin() + getNumArgs(); }
3068
3069	const_arg_iterator arg_begin() const {
3070	return getTrailingStmts() + PREARGS_START + getNumPreArgs();
3071	}
3072	const_arg_iterator arg_end() const { return arg_begin() + getNumArgs(); }
3073
3074	/// This method provides fast access to all the subexpressions of
3075	/// a CallExpr without going through the slower virtual child_iterator
3076	/// interface. This provides efficient reverse iteration of the
3077	/// subexpressions. This is currently used for CFG construction.
3078	ArrayRef<Stmt *> getRawSubExprs() {
3079	return llvm::ArrayRef(getTrailingStmts(),
3080	PREARGS_START + getNumPreArgs() + getNumArgs());
3081	}
3082
3083	/// Get FPOptionsOverride from trailing storage.
3084	FPOptionsOverride getStoredFPFeatures() const {
3085	assert(hasStoredFPFeatures());
3086	return *getTrailingFPFeatures();
3087	}
3088	/// Set FPOptionsOverride in trailing storage. Used only by Serialization.
3089	void setStoredFPFeatures(FPOptionsOverride F) {
3090	assert(hasStoredFPFeatures());
3091	*getTrailingFPFeatures() = F;
3092	}
3093
3094	/// Get the FP features status of this operator. Only meaningful for
3095	/// operations on floating point types.
3096	FPOptions getFPFeaturesInEffect(const LangOptions &LO) const {
3097	if (hasStoredFPFeatures())
3098	return getStoredFPFeatures().applyOverrides(LO);
3099	return FPOptions::defaultWithoutTrailingStorage(LO);
3100	}
3101
3102	FPOptionsOverride getFPFeatures() const {
3103	if (hasStoredFPFeatures())
3104	return getStoredFPFeatures();
3105	return FPOptionsOverride();
3106	}
3107
3108	/// getBuiltinCallee - If this is a call to a builtin, return the builtin ID
3109	/// of the callee. If not, return 0.
3110	unsigned getBuiltinCallee() const;
3111
3112	/// Returns \c true if this is a call to a builtin which does not
3113	/// evaluate side-effects within its arguments.
3114	bool isUnevaluatedBuiltinCall(const ASTContext &Ctx) const;
3115
3116	/// getCallReturnType - Get the return type of the call expr. This is not
3117	/// always the type of the expr itself, if the return type is a reference
3118	/// type.
3119	QualType getCallReturnType(const ASTContext &Ctx) const;
3120
3121	/// Returns the WarnUnusedResultAttr that is either declared on the called
3122	/// function, or its return type declaration.
3123	const Attr *getUnusedResultAttr(const ASTContext &Ctx) const;
3124
3125	/// Returns true if this call expression should warn on unused results.
3126	bool hasUnusedResultAttr(const ASTContext &Ctx) const {
3127	return getUnusedResultAttr(Ctx) != nullptr;
3128	}
3129
3130	SourceLocation getRParenLoc() const { return RParenLoc; }
3131	void setRParenLoc(SourceLocation L) { RParenLoc = L; }
3132
3133	SourceLocation getBeginLoc() const LLVM_READONLY;
3134	SourceLocation getEndLoc() const LLVM_READONLY;
3135
3136	/// Return true if this is a call to __assume() or __builtin_assume() with
3137	/// a non-value-dependent constant parameter evaluating as false.
3138	bool isBuiltinAssumeFalse(const ASTContext &Ctx) const;
3139
3140	/// Used by Sema to implement MSVC-compatible delayed name lookup.
3141	/// (Usually Exprs themselves should set dependence).
3142	void markDependentForPostponedNameLookup() {
3143	setDependence(getDependence() | ExprDependence::TypeValueInstantiation);
3144	}
3145
3146	bool isCallToStdMove() const;
3147
3148	static bool classof(const Stmt *T) {
3149	return T->getStmtClass() >= firstCallExprConstant &&
3150	T->getStmtClass() <= lastCallExprConstant;
3151	}
3152
3153	// Iterators
3154	child_range children() {
3155	return child_range(getTrailingStmts(), getTrailingStmts() + PREARGS_START +
3156	getNumPreArgs() + getNumArgs());
3157	}
3158
3159	const_child_range children() const {
3160	return const_child_range(getTrailingStmts(),
3161	getTrailingStmts() + PREARGS_START +
3162	getNumPreArgs() + getNumArgs());
3163	}
3164	};
3165
3166	/// MemberExpr - [C99 6.5.2.3] Structure and Union Members. X->F and X.F.
3167	///
3168	class MemberExpr final
3169	: public Expr,
3170	private llvm::TrailingObjects<MemberExpr, NestedNameSpecifierLoc,
3171	DeclAccessPair, ASTTemplateKWAndArgsInfo,
3172	TemplateArgumentLoc> {
3173	friend class ASTReader;
3174	friend class ASTStmtReader;
3175	friend class ASTStmtWriter;
3176	friend TrailingObjects;
3177
3178	/// Base - the expression for the base pointer or structure references. In
3179	/// X.F, this is "X".
3180	Stmt *Base;
3181
3182	/// MemberDecl - This is the decl being referenced by the field/member name.
3183	/// In X.F, this is the decl referenced by F.
3184	ValueDecl *MemberDecl;
3185
3186	/// MemberDNLoc - Provides source/type location info for the
3187	/// declaration name embedded in MemberDecl.
3188	DeclarationNameLoc MemberDNLoc;
3189
3190	/// MemberLoc - This is the location of the member name.
3191	SourceLocation MemberLoc;
3192
3193	size_t numTrailingObjects(OverloadToken<NestedNameSpecifierLoc>) const {
3194	return hasQualifier();
3195	}
3196
3197	size_t numTrailingObjects(OverloadToken<DeclAccessPair>) const {
3198	return hasFoundDecl();
3199	}
3200
3201	size_t numTrailingObjects(OverloadToken<ASTTemplateKWAndArgsInfo>) const {
3202	return hasTemplateKWAndArgsInfo();
3203	}
3204
3205	bool hasFoundDecl() const { return MemberExprBits.HasFoundDecl; }
3206
3207	bool hasTemplateKWAndArgsInfo() const {
3208	return MemberExprBits.HasTemplateKWAndArgsInfo;
3209	}
3210
3211	MemberExpr(Expr *Base, bool IsArrow, SourceLocation OperatorLoc,
3212	NestedNameSpecifierLoc QualifierLoc, SourceLocation TemplateKWLoc,
3213	ValueDecl *MemberDecl, DeclAccessPair FoundDecl,
3214	const DeclarationNameInfo &NameInfo,
3215	const TemplateArgumentListInfo *TemplateArgs, QualType T,
3216	ExprValueKind VK, ExprObjectKind OK, NonOdrUseReason NOUR);
3217	MemberExpr(EmptyShell Empty)
3218	: Expr(MemberExprClass, Empty), Base(), MemberDecl() {}
3219
3220	public:
3221	static MemberExpr *Create(const ASTContext &C, Expr *Base, bool IsArrow,
3222	SourceLocation OperatorLoc,
3223	NestedNameSpecifierLoc QualifierLoc,
3224	SourceLocation TemplateKWLoc, ValueDecl *MemberDecl,
3225	DeclAccessPair FoundDecl,
3226	DeclarationNameInfo MemberNameInfo,
3227	const TemplateArgumentListInfo *TemplateArgs,
3228	QualType T, ExprValueKind VK, ExprObjectKind OK,
3229	NonOdrUseReason NOUR);
3230
3231	/// Create an implicit MemberExpr, with no location, qualifier, template
3232	/// arguments, and so on. Suitable only for non-static member access.
3233	static MemberExpr *CreateImplicit(const ASTContext &C, Expr *Base,
3234	bool IsArrow, ValueDecl *MemberDecl,
3235	QualType T, ExprValueKind VK,
3236	ExprObjectKind OK) {
3237	return Create(C, Base, IsArrow, OperatorLoc: SourceLocation(), QualifierLoc: NestedNameSpecifierLoc(),
3238	TemplateKWLoc: SourceLocation(), MemberDecl,
3239	FoundDecl: DeclAccessPair::make(D: MemberDecl, AS: MemberDecl->getAccess()),
3240	MemberNameInfo: DeclarationNameInfo(), TemplateArgs: nullptr, T, VK, OK, NOUR: NOUR_None);
3241	}
3242
3243	static MemberExpr *CreateEmpty(const ASTContext &Context, bool HasQualifier,
3244	bool HasFoundDecl,
3245	bool HasTemplateKWAndArgsInfo,
3246	unsigned NumTemplateArgs);
3247
3248	void setBase(Expr *E) { Base = E; }
3249	Expr *getBase() const { return cast<Expr>(Val: Base); }
3250
3251	/// Retrieve the member declaration to which this expression refers.
3252	///
3253	/// The returned declaration will be a FieldDecl or (in C++) a VarDecl (for
3254	/// static data members), a CXXMethodDecl, or an EnumConstantDecl.
3255	ValueDecl *getMemberDecl() const { return MemberDecl; }
3256	void setMemberDecl(ValueDecl *D);
3257
3258	/// Retrieves the declaration found by lookup.
3259	DeclAccessPair getFoundDecl() const {
3260	if (!hasFoundDecl())
3261	return DeclAccessPair::make(D: getMemberDecl(),
3262	AS: getMemberDecl()->getAccess());
3263	return *getTrailingObjects<DeclAccessPair>();
3264	}
3265
3266	/// Determines whether this member expression actually had
3267	/// a C++ nested-name-specifier prior to the name of the member, e.g.,
3268	/// x->Base::foo.
3269	bool hasQualifier() const { return MemberExprBits.HasQualifier; }
3270
3271	/// If the member name was qualified, retrieves the
3272	/// nested-name-specifier that precedes the member name, with source-location
3273	/// information.
3274	NestedNameSpecifierLoc getQualifierLoc() const {
3275	if (!hasQualifier())
3276	return NestedNameSpecifierLoc();
3277	return *getTrailingObjects<NestedNameSpecifierLoc>();
3278	}
3279
3280	/// If the member name was qualified, retrieves the
3281	/// nested-name-specifier that precedes the member name. Otherwise, returns
3282	/// NULL.
3283	NestedNameSpecifier *getQualifier() const {
3284	return getQualifierLoc().getNestedNameSpecifier();
3285	}
3286
3287	/// Retrieve the location of the template keyword preceding
3288	/// the member name, if any.
3289	SourceLocation getTemplateKeywordLoc() const {
3290	if (!hasTemplateKWAndArgsInfo())
3291	return SourceLocation();
3292	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->TemplateKWLoc;
3293	}
3294
3295	/// Retrieve the location of the left angle bracket starting the
3296	/// explicit template argument list following the member name, if any.
3297	SourceLocation getLAngleLoc() const {
3298	if (!hasTemplateKWAndArgsInfo())
3299	return SourceLocation();
3300	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->LAngleLoc;
3301	}
3302
3303	/// Retrieve the location of the right angle bracket ending the
3304	/// explicit template argument list following the member name, if any.
3305	SourceLocation getRAngleLoc() const {
3306	if (!hasTemplateKWAndArgsInfo())
3307	return SourceLocation();
3308	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->RAngleLoc;
3309	}
3310
3311	/// Determines whether the member name was preceded by the template keyword.
3312	bool hasTemplateKeyword() const { return getTemplateKeywordLoc().isValid(); }
3313
3314	/// Determines whether the member name was followed by an
3315	/// explicit template argument list.
3316	bool hasExplicitTemplateArgs() const { return getLAngleLoc().isValid(); }
3317
3318	/// Copies the template arguments (if present) into the given
3319	/// structure.
3320	void copyTemplateArgumentsInto(TemplateArgumentListInfo &List) const {
3321	if (hasExplicitTemplateArgs())
3322	getTrailingObjects<ASTTemplateKWAndArgsInfo>()->copyInto(
3323	getTrailingObjects<TemplateArgumentLoc>(), List);
3324	}
3325
3326	/// Retrieve the template arguments provided as part of this
3327	/// template-id.
3328	const TemplateArgumentLoc *getTemplateArgs() const {
3329	if (!hasExplicitTemplateArgs())
3330	return nullptr;
3331
3332	return getTrailingObjects<TemplateArgumentLoc>();
3333	}
3334
3335	/// Retrieve the number of template arguments provided as part of this
3336	/// template-id.
3337	unsigned getNumTemplateArgs() const {
3338	if (!hasExplicitTemplateArgs())
3339	return 0;
3340
3341	return getTrailingObjects<ASTTemplateKWAndArgsInfo>()->NumTemplateArgs;
3342	}
3343
3344	ArrayRef<TemplateArgumentLoc> template_arguments() const {
3345	return {getTemplateArgs(), getNumTemplateArgs()};
3346	}
3347
3348	/// Retrieve the member declaration name info.
3349	DeclarationNameInfo getMemberNameInfo() const {
3350	return DeclarationNameInfo(MemberDecl->getDeclName(),
3351	MemberLoc, MemberDNLoc);
3352	}
3353
3354	SourceLocation getOperatorLoc() const { return MemberExprBits.OperatorLoc; }
3355
3356	bool isArrow() const { return MemberExprBits.IsArrow; }
3357	void setArrow(bool A) { MemberExprBits.IsArrow = A; }
3358
3359	/// getMemberLoc - Return the location of the "member", in X->F, it is the
3360	/// location of 'F'.
3361	SourceLocation getMemberLoc() const { return MemberLoc; }
3362	void setMemberLoc(SourceLocation L) { MemberLoc = L; }
3363
3364	SourceLocation getBeginLoc() const LLVM_READONLY;
3365	SourceLocation getEndLoc() const LLVM_READONLY;
3366
3367	SourceLocation getExprLoc() const LLVM_READONLY { return MemberLoc; }
3368
3369	/// Determine whether the base of this explicit is implicit.
3370	bool isImplicitAccess() const {
3371	return getBase() && getBase()->isImplicitCXXThis();
3372	}
3373
3374	/// Returns true if this member expression refers to a method that
3375	/// was resolved from an overloaded set having size greater than 1.
3376	bool hadMultipleCandidates() const {
3377	return MemberExprBits.HadMultipleCandidates;
3378	}
3379	/// Sets the flag telling whether this expression refers to
3380	/// a method that was resolved from an overloaded set having size
3381	/// greater than 1.
3382	void setHadMultipleCandidates(bool V = true) {
3383	MemberExprBits.HadMultipleCandidates = V;
3384	}
3385
3386	/// Returns true if virtual dispatch is performed.
3387	/// If the member access is fully qualified, (i.e. X::f()), virtual
3388	/// dispatching is not performed. In -fapple-kext mode qualified
3389	/// calls to virtual method will still go through the vtable.
3390	bool performsVirtualDispatch(const LangOptions &LO) const {
3391	return LO.AppleKext || !hasQualifier();
3392	}
3393
3394	/// Is this expression a non-odr-use reference, and if so, why?
3395	/// This is only meaningful if the named member is a static member.
3396	NonOdrUseReason isNonOdrUse() const {
3397	return static_cast<NonOdrUseReason>(MemberExprBits.NonOdrUseReason);
3398	}
3399
3400	static bool classof(const Stmt *T) {
3401	return T->getStmtClass() == MemberExprClass;
3402	}
3403
3404	// Iterators
3405	child_range children() { return child_range(&Base, &Base+1); }
3406	const_child_range children() const {
3407	return const_child_range(&Base, &Base + 1);
3408	}
3409	};
3410
3411	/// CompoundLiteralExpr - [C99 6.5.2.5]
3412	///
3413	class CompoundLiteralExpr : public Expr {
3414	/// LParenLoc - If non-null, this is the location of the left paren in a
3415	/// compound literal like "(int){4}". This can be null if this is a
3416	/// synthesized compound expression.
3417	SourceLocation LParenLoc;
3418
3419	/// The type as written. This can be an incomplete array type, in
3420	/// which case the actual expression type will be different.
3421	/// The int part of the pair stores whether this expr is file scope.
3422	llvm::PointerIntPair<TypeSourceInfo *, 1, bool> TInfoAndScope;
3423	Stmt *Init;
3424	public:
3425	CompoundLiteralExpr(SourceLocation lparenloc, TypeSourceInfo *tinfo,
3426	QualType T, ExprValueKind VK, Expr *init, bool fileScope)
3427	: Expr(CompoundLiteralExprClass, T, VK, OK_Ordinary),
3428	LParenLoc(lparenloc), TInfoAndScope(tinfo, fileScope), Init(init) {
3429	setDependence(computeDependence(E: this));
3430	}
3431
3432	/// Construct an empty compound literal.
3433	explicit CompoundLiteralExpr(EmptyShell Empty)
3434	: Expr(CompoundLiteralExprClass, Empty) { }
3435
3436	const Expr *getInitializer() const { return cast<Expr>(Val: Init); }
3437	Expr *getInitializer() { return cast<Expr>(Val: Init); }
3438	void setInitializer(Expr *E) { Init = E; }
3439
3440	bool isFileScope() const { return TInfoAndScope.getInt(); }
3441	void setFileScope(bool FS) { TInfoAndScope.setInt(FS); }
3442
3443	SourceLocation getLParenLoc() const { return LParenLoc; }
3444	void setLParenLoc(SourceLocation L) { LParenLoc = L; }
3445
3446	TypeSourceInfo *getTypeSourceInfo() const {
3447	return TInfoAndScope.getPointer();
3448	}
3449	void setTypeSourceInfo(TypeSourceInfo *tinfo) {
3450	TInfoAndScope.setPointer(tinfo);
3451	}
3452
3453	SourceLocation getBeginLoc() const LLVM_READONLY {
3454	// FIXME: Init should never be null.
3455	if (!Init)
3456	return SourceLocation();
3457	if (LParenLoc.isInvalid())
3458	return Init->getBeginLoc();
3459	return LParenLoc;
3460	}
3461	SourceLocation getEndLoc() const LLVM_READONLY {
3462	// FIXME: Init should never be null.
3463	if (!Init)
3464	return SourceLocation();
3465	return Init->getEndLoc();
3466	}
3467
3468	static bool classof(const Stmt *T) {
3469	return T->getStmtClass() == CompoundLiteralExprClass;
3470	}
3471
3472	// Iterators
3473	child_range children() { return child_range(&Init, &Init+1); }
3474	const_child_range children() const {
3475	return const_child_range(&Init, &Init + 1);
3476	}
3477	};
3478
3479	/// CastExpr - Base class for type casts, including both implicit
3480	/// casts (ImplicitCastExpr) and explicit casts that have some
3481	/// representation in the source code (ExplicitCastExpr's derived
3482	/// classes).
3483	class CastExpr : public Expr {
3484	Stmt *Op;
3485
3486	bool CastConsistency() const;
3487
3488	const CXXBaseSpecifier * const *path_buffer() const {
3489	return const_cast<CastExpr*>(this)->path_buffer();
3490	}
3491	CXXBaseSpecifier **path_buffer();
3492
3493	friend class ASTStmtReader;
3494
3495	protected:
3496	CastExpr(StmtClass SC, QualType ty, ExprValueKind VK, const CastKind kind,
3497	Expr *op, unsigned BasePathSize, bool HasFPFeatures)
3498	: Expr(SC, ty, VK, OK_Ordinary), Op(op) {
3499	CastExprBits.Kind = kind;
3500	CastExprBits.PartOfExplicitCast = false;
3501	CastExprBits.BasePathSize = BasePathSize;
3502	assert((CastExprBits.BasePathSize == BasePathSize) &&
3503	"BasePathSize overflow!");
3504	assert(CastConsistency());
3505	CastExprBits.HasFPFeatures = HasFPFeatures;
3506	}
3507
3508	/// Construct an empty cast.
3509	CastExpr(StmtClass SC, EmptyShell Empty, unsigned BasePathSize,
3510	bool HasFPFeatures)
3511	: Expr(SC, Empty) {
3512	CastExprBits.PartOfExplicitCast = false;
3513	CastExprBits.BasePathSize = BasePathSize;
3514	CastExprBits.HasFPFeatures = HasFPFeatures;
3515	assert((CastExprBits.BasePathSize == BasePathSize) &&
3516	"BasePathSize overflow!");
3517	}
3518
3519	/// Return a pointer to the trailing FPOptions.
3520	/// \pre hasStoredFPFeatures() == true
3521	FPOptionsOverride *getTrailingFPFeatures();
3522	const FPOptionsOverride *getTrailingFPFeatures() const {
3523	return const_cast<CastExpr *>(this)->getTrailingFPFeatures();
3524	}
3525
3526	public:
3527	CastKind getCastKind() const { return (CastKind) CastExprBits.Kind; }
3528	void setCastKind(CastKind K) { CastExprBits.Kind = K; }
3529
3530	static const char *getCastKindName(CastKind CK);
3531	const char *getCastKindName() const { return getCastKindName(CK: getCastKind()); }
3532
3533	Expr *getSubExpr() { return cast<Expr>(Val: Op); }
3534	const Expr *getSubExpr() const { return cast<Expr>(Val: Op); }
3535	void setSubExpr(Expr *E) { Op = E; }
3536
3537	/// Retrieve the cast subexpression as it was written in the source
3538	/// code, looking through any implicit casts or other intermediate nodes
3539	/// introduced by semantic analysis.
3540	Expr *getSubExprAsWritten();
3541	const Expr *getSubExprAsWritten() const {
3542	return const_cast<CastExpr *>(this)->getSubExprAsWritten();
3543	}
3544
3545	/// If this cast applies a user-defined conversion, retrieve the conversion
3546	/// function that it invokes.
3547	NamedDecl *getConversionFunction() const;
3548
3549	typedef CXXBaseSpecifier **path_iterator;
3550	typedef const CXXBaseSpecifier *const *path_const_iterator;
3551	bool path_empty() const { return path_size() == 0; }
3552	unsigned path_size() const { return CastExprBits.BasePathSize; }
3553	path_iterator path_begin() { return path_buffer(); }
3554	path_iterator path_end() { return path_buffer() + path_size(); }
3555	path_const_iterator path_begin() const { return path_buffer(); }
3556	path_const_iterator path_end() const { return path_buffer() + path_size(); }
3557
3558	/// Path through the class hierarchy taken by casts between base and derived
3559	/// classes (see implementation of `CastConsistency()` for a full list of
3560	/// cast kinds that have a path).
3561	///
3562	/// For each derived-to-base edge in the path, the path contains a
3563	/// `CXXBaseSpecifier` for the base class of that edge; the entries are
3564	/// ordered from derived class to base class.
3565	///
3566	/// For example, given classes `Base`, `Intermediate : public Base` and
3567	/// `Derived : public Intermediate`, the path for a cast from `Derived *` to
3568	/// `Base *` contains two entries: One for `Intermediate`, and one for `Base`,
3569	/// in that order.
3570	llvm::iterator_range<path_iterator> path() {
3571	return llvm::make_range(x: path_begin(), y: path_end());
3572	}
3573	llvm::iterator_range<path_const_iterator> path() const {
3574	return llvm::make_range(x: path_begin(), y: path_end());
3575	}
3576
3577	const FieldDecl *getTargetUnionField() const {
3578	assert(getCastKind() == CK_ToUnion);
3579	return getTargetFieldForToUnionCast(getType(), getSubExpr()->getType());
3580	}
3581
3582	bool hasStoredFPFeatures() const { return CastExprBits.HasFPFeatures; }
3583
3584	/// Get FPOptionsOverride from trailing storage.
3585	FPOptionsOverride getStoredFPFeatures() const {
3586	assert(hasStoredFPFeatures());
3587	return *getTrailingFPFeatures();
3588	}
3589
3590	/// Get the FP features status of this operation. Only meaningful for
3591	/// operations on floating point types.
3592	FPOptions getFPFeaturesInEffect(const LangOptions &LO) const {
3593	if (hasStoredFPFeatures())
3594	return getStoredFPFeatures().applyOverrides(LO);
3595	return FPOptions::defaultWithoutTrailingStorage(LO);
3596	}
3597
3598	FPOptionsOverride getFPFeatures() const {
3599	if (hasStoredFPFeatures())
3600	return getStoredFPFeatures();
3601	return FPOptionsOverride();
3602	}
3603
3604	/// Return
3605	// True : if this conversion changes the volatile-ness of a gl-value.
3606	// Qualification conversions on gl-values currently use CK_NoOp, but
3607	// it's important to recognize volatile-changing conversions in
3608	// clients code generation that normally eagerly peephole loads. Note
3609	// that the query is answering for this specific node; Sema may
3610	// produce multiple cast nodes for any particular conversion sequence.
3611	// False : Otherwise.
3612	bool changesVolatileQualification() const {
3613	return (isGLValue() && (getType().isVolatileQualified() !=
3614	getSubExpr()->getType().isVolatileQualified()));
3615	}
3616
3617	static const FieldDecl *getTargetFieldForToUnionCast(QualType unionType,
3618	QualType opType);
3619	static const FieldDecl *getTargetFieldForToUnionCast(const RecordDecl *RD,
3620	QualType opType);
3621
3622	static bool classof(const Stmt *T) {
3623	return T->getStmtClass() >= firstCastExprConstant &&
3624	T->getStmtClass() <= lastCastExprConstant;
3625	}
3626
3627	// Iterators
3628	child_range children() { return child_range(&Op, &Op+1); }
3629	const_child_range children() const { return const_child_range(&Op, &Op + 1); }
3630	};
3631
3632	/// ImplicitCastExpr - Allows us to explicitly represent implicit type
3633	/// conversions, which have no direct representation in the original
3634	/// source code. For example: converting T[]->T*, void f()->void
3635	/// (*f)(), float->double, short->int, etc.
3636	///
3637	/// In C, implicit casts always produce rvalues. However, in C++, an
3638	/// implicit cast whose result is being bound to a reference will be
3639	/// an lvalue or xvalue. For example:
3640	///
3641	/// @code
3642	/// class Base { };
3643	/// class Derived : public Base { };
3644	/// Derived &&ref();
3645	/// void f(Derived d) {
3646	/// Base& b = d; // initializer is an ImplicitCastExpr
3647	/// // to an lvalue of type Base
3648	/// Base&& r = ref(); // initializer is an ImplicitCastExpr
3649	/// // to an xvalue of type Base
3650	/// }
3651	/// @endcode
3652	class ImplicitCastExpr final
3653	: public CastExpr,
3654	private llvm::TrailingObjects<ImplicitCastExpr, CXXBaseSpecifier *,
3655	FPOptionsOverride> {
3656
3657	ImplicitCastExpr(QualType ty, CastKind kind, Expr *op,
3658	unsigned BasePathLength, FPOptionsOverride FPO,
3659	ExprValueKind VK)
3660	: CastExpr(ImplicitCastExprClass, ty, VK, kind, op, BasePathLength,
3661	FPO.requiresTrailingStorage()) {
3662	setDependence(computeDependence(E: this));
3663	if (hasStoredFPFeatures())
3664	*getTrailingFPFeatures() = FPO;
3665	}
3666
3667	/// Construct an empty implicit cast.
3668	explicit ImplicitCastExpr(EmptyShell Shell, unsigned PathSize,
3669	bool HasFPFeatures)
3670	: CastExpr(ImplicitCastExprClass, Shell, PathSize, HasFPFeatures) {}
3671
3672	unsigned numTrailingObjects(OverloadToken<CXXBaseSpecifier *>) const {
3673	return path_size();
3674	}
3675
3676	public:
3677	enum OnStack_t { OnStack };
3678	ImplicitCastExpr(OnStack_t _, QualType ty, CastKind kind, Expr *op,
3679	ExprValueKind VK, FPOptionsOverride FPO)
3680	: CastExpr(ImplicitCastExprClass, ty, VK, kind, op, 0,
3681	FPO.requiresTrailingStorage()) {
3682	if (hasStoredFPFeatures())
3683	*getTrailingFPFeatures() = FPO;
3684	}
3685
3686	bool isPartOfExplicitCast() const { return CastExprBits.PartOfExplicitCast; }
3687	void setIsPartOfExplicitCast(bool PartOfExplicitCast) {
3688	CastExprBits.PartOfExplicitCast = PartOfExplicitCast;
3689	}
3690
3691	static ImplicitCastExpr *Create(const ASTContext &Context, QualType T,
3692	CastKind Kind, Expr *Operand,
3693	const CXXCastPath *BasePath,
3694	ExprValueKind Cat, FPOptionsOverride FPO);
3695
3696	static ImplicitCastExpr *CreateEmpty(const ASTContext &Context,
3697	unsigned PathSize, bool HasFPFeatures);
3698
3699	SourceLocation getBeginLoc() const LLVM_READONLY {
3700	return getSubExpr()->getBeginLoc();
3701	}
3702	SourceLocation getEndLoc() const LLVM_READONLY {
3703	return getSubExpr()->getEndLoc();
3704	}
3705
3706	static bool classof(const Stmt *T) {
3707	return T->getStmtClass() == ImplicitCastExprClass;
3708	}
3709
3710	friend TrailingObjects;
3711	friend class CastExpr;
3712	};
3713
3714	/// ExplicitCastExpr - An explicit cast written in the source
3715	/// code.
3716	///
3717	/// This class is effectively an abstract class, because it provides
3718	/// the basic representation of an explicitly-written cast without
3719	/// specifying which kind of cast (C cast, functional cast, static
3720	/// cast, etc.) was written; specific derived classes represent the
3721	/// particular style of cast and its location information.
3722	///
3723	/// Unlike implicit casts, explicit cast nodes have two different
3724	/// types: the type that was written into the source code, and the
3725	/// actual type of the expression as determined by semantic
3726	/// analysis. These types may differ slightly. For example, in C++ one
3727	/// can cast to a reference type, which indicates that the resulting
3728	/// expression will be an lvalue or xvalue. The reference type, however,
3729	/// will not be used as the type of the expression.
3730	class ExplicitCastExpr : public CastExpr {
3731	/// TInfo - Source type info for the (written) type
3732	/// this expression is casting to.
3733	TypeSourceInfo *TInfo;
3734
3735	protected:
3736	ExplicitCastExpr(StmtClass SC, QualType exprTy, ExprValueKind VK,
3737	CastKind kind, Expr *op, unsigned PathSize,
3738	bool HasFPFeatures, TypeSourceInfo *writtenTy)
3739	: CastExpr(SC, exprTy, VK, kind, op, PathSize, HasFPFeatures),
3740	TInfo(writtenTy) {
3741	setDependence(computeDependence(E: this));
3742	}
3743
3744	/// Construct an empty explicit cast.
3745	ExplicitCastExpr(StmtClass SC, EmptyShell Shell, unsigned PathSize,
3746	bool HasFPFeatures)
3747	: CastExpr(SC, Shell, PathSize, HasFPFeatures) {}
3748
3749	public:
3750	/// getTypeInfoAsWritten - Returns the type source info for the type
3751	/// that this expression is casting to.
3752	TypeSourceInfo *getTypeInfoAsWritten() const { return TInfo; }
3753	void setTypeInfoAsWritten(TypeSourceInfo *writtenTy) { TInfo = writtenTy; }
3754
3755	/// getTypeAsWritten - Returns the type that this expression is
3756	/// casting to, as written in the source code.
3757	QualType getTypeAsWritten() const { return TInfo->getType(); }
3758
3759	static bool classof(const Stmt *T) {
3760	return T->getStmtClass() >= firstExplicitCastExprConstant &&
3761	T->getStmtClass() <= lastExplicitCastExprConstant;
3762	}
3763	};
3764
3765	/// CStyleCastExpr - An explicit cast in C (C99 6.5.4) or a C-style
3766	/// cast in C++ (C++ [expr.cast]), which uses the syntax
3767	/// (Type)expr. For example: @c (int)f.
3768	class CStyleCastExpr final
3769	: public ExplicitCastExpr,
3770	private llvm::TrailingObjects<CStyleCastExpr, CXXBaseSpecifier *,
3771	FPOptionsOverride> {
3772	SourceLocation LPLoc; // the location of the left paren
3773	SourceLocation RPLoc; // the location of the right paren
3774
3775	CStyleCastExpr(QualType exprTy, ExprValueKind vk, CastKind kind, Expr *op,
3776	unsigned PathSize, FPOptionsOverride FPO,
3777	TypeSourceInfo *writtenTy, SourceLocation l, SourceLocation r)
3778	: ExplicitCastExpr(CStyleCastExprClass, exprTy, vk, kind, op, PathSize,
3779	FPO.requiresTrailingStorage(), writtenTy),
3780	LPLoc(l), RPLoc(r) {
3781	if (hasStoredFPFeatures())
3782	*getTrailingFPFeatures() = FPO;
3783	}
3784
3785	/// Construct an empty C-style explicit cast.
3786	explicit CStyleCastExpr(EmptyShell Shell, unsigned PathSize,
3787	bool HasFPFeatures)
3788	: ExplicitCastExpr(CStyleCastExprClass, Shell, PathSize, HasFPFeatures) {}
3789
3790	unsigned numTrailingObjects(OverloadToken<CXXBaseSpecifier *>) const {
3791	return path_size();
3792	}
3793
3794	public:
3795	static CStyleCastExpr *
3796	Create(const ASTContext &Context, QualType T, ExprValueKind VK, CastKind K,
3797	Expr *Op, const CXXCastPath *BasePath, FPOptionsOverride FPO,
3798	TypeSourceInfo *WrittenTy, SourceLocation L, SourceLocation R);
3799
3800	static CStyleCastExpr *CreateEmpty(const ASTContext &Context,
3801	unsigned PathSize, bool HasFPFeatures);
3802
3803	SourceLocation getLParenLoc() const { return LPLoc; }
3804	void setLParenLoc(SourceLocation L) { LPLoc = L; }
3805
3806	SourceLocation getRParenLoc() const { return RPLoc; }
3807	void setRParenLoc(SourceLocation L) { RPLoc = L; }
3808
3809	SourceLocation getBeginLoc() const LLVM_READONLY { return LPLoc; }
3810	SourceLocation getEndLoc() const LLVM_READONLY {
3811	return getSubExpr()->getEndLoc();
3812	}
3813
3814	static bool classof(const Stmt *T) {
3815	return T->getStmtClass() == CStyleCastExprClass;
3816	}
3817
3818	friend TrailingObjects;
3819	friend class CastExpr;
3820	};
3821
3822	/// A builtin binary operation expression such as "x + y" or "x <= y".
3823	///
3824	/// This expression node kind describes a builtin binary operation,
3825	/// such as "x + y" for integer values "x" and "y". The operands will
3826	/// already have been converted to appropriate types (e.g., by
3827	/// performing promotions or conversions).
3828	///
3829	/// In C++, where operators may be overloaded, a different kind of
3830	/// expression node (CXXOperatorCallExpr) is used to express the
3831	/// invocation of an overloaded operator with operator syntax. Within
3832	/// a C++ template, whether BinaryOperator or CXXOperatorCallExpr is
3833	/// used to store an expression "x + y" depends on the subexpressions
3834	/// for x and y. If neither x or y is type-dependent, and the "+"
3835	/// operator resolves to a built-in operation, BinaryOperator will be
3836	/// used to express the computation (x and y may still be
3837	/// value-dependent). If either x or y is type-dependent, or if the
3838	/// "+" resolves to an overloaded operator, CXXOperatorCallExpr will
3839	/// be used to express the computation.
3840	class BinaryOperator : public Expr {
3841	enum { LHS, RHS, END_EXPR };
3842	Stmt *SubExprs[END_EXPR];
3843
3844	public:
3845	typedef BinaryOperatorKind Opcode;
3846
3847	protected:
3848	size_t offsetOfTrailingStorage() const;
3849
3850	/// Return a pointer to the trailing FPOptions
3851	FPOptionsOverride *getTrailingFPFeatures() {
3852	assert(BinaryOperatorBits.HasFPFeatures);
3853	return reinterpret_cast<FPOptionsOverride *>(
3854	reinterpret_cast<char *>(this) + offsetOfTrailingStorage());
3855	}
3856	const FPOptionsOverride *getTrailingFPFeatures() const {
3857	assert(BinaryOperatorBits.HasFPFeatures);
3858	return reinterpret_cast<const FPOptionsOverride *>(
3859	reinterpret_cast<const char *>(this) + offsetOfTrailingStorage());
3860	}
3861
3862	/// Build a binary operator, assuming that appropriate storage has been
3863	/// allocated for the trailing objects when needed.
3864	BinaryOperator(const ASTContext &Ctx, Expr *lhs, Expr *rhs, Opcode opc,
3865	QualType ResTy, ExprValueKind VK, ExprObjectKind OK,
3866	SourceLocation opLoc, FPOptionsOverride FPFeatures);
3867
3868	/// Construct an empty binary operator.
3869	explicit BinaryOperator(EmptyShell Empty) : Expr(BinaryOperatorClass, Empty) {
3870	BinaryOperatorBits.Opc = BO_Comma;
3871	}
3872
3873	public:
3874	static BinaryOperator *CreateEmpty(const ASTContext &C, bool hasFPFeatures);
3875
3876	static BinaryOperator *Create(const ASTContext &C, Expr *lhs, Expr *rhs,
3877	Opcode opc, QualType ResTy, ExprValueKind VK,
3878	ExprObjectKind OK, SourceLocation opLoc,
3879	FPOptionsOverride FPFeatures);
3880	SourceLocation getExprLoc() const { return getOperatorLoc(); }
3881	SourceLocation getOperatorLoc() const { return BinaryOperatorBits.OpLoc; }
3882	void setOperatorLoc(SourceLocation L) { BinaryOperatorBits.OpLoc = L; }
3883
3884	Opcode getOpcode() const {
3885	return static_cast<Opcode>(BinaryOperatorBits.Opc);
3886	}
3887	void setOpcode(Opcode Opc) { BinaryOperatorBits.Opc = Opc; }
3888
3889	Expr *getLHS() const { return cast<Expr>(Val: SubExprs[LHS]); }
3890	void setLHS(Expr *E) { SubExprs[LHS] = E; }
3891	Expr *getRHS() const { return cast<Expr>(Val: SubExprs[RHS]); }
3892	void setRHS(Expr *E) { SubExprs[RHS] = E; }
3893
3894	SourceLocation getBeginLoc() const LLVM_READONLY {
3895	return getLHS()->getBeginLoc();
3896	}
3897	SourceLocation getEndLoc() const LLVM_READONLY {
3898	return getRHS()->getEndLoc();
3899	}
3900
3901	/// getOpcodeStr - Turn an Opcode enum value into the punctuation char it
3902	/// corresponds to, e.g. "<<=".
3903	static StringRef getOpcodeStr(Opcode Op);
3904
3905	StringRef getOpcodeStr() const { return getOpcodeStr(Op: getOpcode()); }
3906
3907	/// Retrieve the binary opcode that corresponds to the given
3908	/// overloaded operator.
3909	static Opcode getOverloadedOpcode(OverloadedOperatorKind OO);
3910
3911	/// Retrieve the overloaded operator kind that corresponds to
3912	/// the given binary opcode.
3913	static OverloadedOperatorKind getOverloadedOperator(Opcode Opc);
3914
3915	/// predicates to categorize the respective opcodes.
3916	static bool isPtrMemOp(Opcode Opc) {
3917	return Opc == BO_PtrMemD || Opc == BO_PtrMemI;
3918	}
3919	bool isPtrMemOp() const { return isPtrMemOp(Opc: getOpcode()); }
3920
3921	static bool isMultiplicativeOp(Opcode Opc) {
3922	return Opc >= BO_Mul && Opc <= BO_Rem;
3923	}
3924	bool isMultiplicativeOp() const { return isMultiplicativeOp(Opc: getOpcode()); }
3925	static bool isAdditiveOp(Opcode Opc) { return Opc == BO_Add || Opc==BO_Sub; }
3926	bool isAdditiveOp() const { return isAdditiveOp(Opc: getOpcode()); }
3927	static bool isShiftOp(Opcode Opc) { return Opc == BO_Shl || Opc == BO_Shr; }
3928	bool isShiftOp() const { return isShiftOp(Opc: getOpcode()); }
3929
3930	static bool isBitwiseOp(Opcode Opc) { return Opc >= BO_And && Opc <= BO_Or; }
3931	bool isBitwiseOp() const { return isBitwiseOp(Opc: getOpcode()); }
3932
3933	static bool isRelationalOp(Opcode Opc) { return Opc >= BO_LT && Opc<=BO_GE; }
3934	bool isRelationalOp() const { return isRelationalOp(Opc: getOpcode()); }
3935
3936	static bool isEqualityOp(Opcode Opc) { return Opc == BO_EQ || Opc == BO_NE; }
3937	bool isEqualityOp() const { return isEqualityOp(Opc: getOpcode()); }
3938
3939	static bool isComparisonOp(Opcode Opc) { return Opc >= BO_Cmp && Opc<=BO_NE; }
3940	bool isComparisonOp() const { return isComparisonOp(Opc: getOpcode()); }
3941
3942	static bool isCommaOp(Opcode Opc) { return Opc == BO_Comma; }
3943	bool isCommaOp() const { return isCommaOp(Opc: getOpcode()); }
3944
3945	static Opcode negateComparisonOp(Opcode Opc) {
3946	switch (Opc) {
3947	default:
3948	llvm_unreachable("Not a comparison operator.");
3949	case BO_LT: return BO_GE;
3950	case BO_GT: return BO_LE;
3951	case BO_LE: return BO_GT;
3952	case BO_GE: return BO_LT;
3953	case BO_EQ: return BO_NE;
3954	case BO_NE: return BO_EQ;
3955	}
3956	}
3957
3958	static Opcode reverseComparisonOp(Opcode Opc) {
3959	switch (Opc) {
3960	default:
3961	llvm_unreachable("Not a comparison operator.");
3962	case BO_LT: return BO_GT;
3963	case BO_GT: return BO_LT;
3964	case BO_LE: return BO_GE;
3965	case BO_GE: return BO_LE;
3966	case BO_EQ:
3967	case BO_NE:
3968	return Opc;
3969	}
3970	}
3971
3972	static bool isLogicalOp(Opcode Opc) { return Opc == BO_LAnd || Opc==BO_LOr; }
3973	bool isLogicalOp() const { return isLogicalOp(Opc: getOpcode()); }
3974
3975	static bool isAssignmentOp(Opcode Opc) {
3976	return Opc >= BO_Assign && Opc <= BO_OrAssign;
3977	}
3978	bool isAssignmentOp() const { return isAssignmentOp(Opc: getOpcode()); }
3979
3980	static bool isCompoundAssignmentOp(Opcode Opc) {
3981	return Opc > BO_Assign && Opc <= BO_OrAssign;
3982	}
3983	bool isCompoundAssignmentOp() const {
3984	return isCompoundAssignmentOp(Opc: getOpcode());
3985	}
3986	static Opcode getOpForCompoundAssignment(Opcode Opc) {
3987	assert(isCompoundAssignmentOp(Opc));
3988	if (Opc >= BO_AndAssign)
3989	return Opcode(unsigned(Opc) - BO_AndAssign + BO_And);
3990	else
3991	return Opcode(unsigned(Opc) - BO_MulAssign + BO_Mul);
3992	}
3993
3994	static bool isShiftAssignOp(Opcode Opc) {
3995	return Opc == BO_ShlAssign || Opc == BO_ShrAssign;
3996	}
3997	bool isShiftAssignOp() const {
3998	return isShiftAssignOp(Opc: getOpcode());
3999	}
4000
4001	/// Return true if a binary operator using the specified opcode and operands
4002	/// would match the 'p = (i8*)nullptr + n' idiom for casting a pointer-sized
4003	/// integer to a pointer.
4004	static bool isNullPointerArithmeticExtension(ASTContext &Ctx, Opcode Opc,
4005	const Expr *LHS,
4006	const Expr *RHS);
4007
4008	static bool classof(const Stmt *S) {
4009	return S->getStmtClass() >= firstBinaryOperatorConstant &&
4010	S->getStmtClass() <= lastBinaryOperatorConstant;
4011	}
4012
4013	// Iterators
4014	child_range children() {
4015	return child_range(&SubExprs[0], &SubExprs[0]+END_EXPR);
4016	}
4017	const_child_range children() const {
4018	return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
4019	}
4020
4021	/// Set and fetch the bit that shows whether FPFeatures needs to be
4022	/// allocated in Trailing Storage
4023	void setHasStoredFPFeatures(bool B) { BinaryOperatorBits.HasFPFeatures = B; }
4024	bool hasStoredFPFeatures() const { return BinaryOperatorBits.HasFPFeatures; }
4025
4026	/// Get FPFeatures from trailing storage
4027	FPOptionsOverride getStoredFPFeatures() const {
4028	assert(hasStoredFPFeatures());
4029	return *getTrailingFPFeatures();
4030	}
4031	/// Set FPFeatures in trailing storage, used only by Serialization
4032	void setStoredFPFeatures(FPOptionsOverride F) {
4033	assert(BinaryOperatorBits.HasFPFeatures);
4034	*getTrailingFPFeatures() = F;
4035	}
4036
4037	/// Get the FP features status of this operator. Only meaningful for
4038	/// operations on floating point types.
4039	FPOptions getFPFeaturesInEffect(const LangOptions &LO) const {
4040	if (BinaryOperatorBits.HasFPFeatures)
4041	return getStoredFPFeatures().applyOverrides(LO);
4042	return FPOptions::defaultWithoutTrailingStorage(LO);
4043	}
4044
4045	// This is used in ASTImporter
4046	FPOptionsOverride getFPFeatures() const {
4047	if (BinaryOperatorBits.HasFPFeatures)
4048	return getStoredFPFeatures();
4049	return FPOptionsOverride();
4050	}
4051
4052	/// Get the FP contractability status of this operator. Only meaningful for
4053	/// operations on floating point types.
4054	bool isFPContractableWithinStatement(const LangOptions &LO) const {
4055	return getFPFeaturesInEffect(LO).allowFPContractWithinStatement();
4056	}
4057
4058	/// Get the FENV_ACCESS status of this operator. Only meaningful for
4059	/// operations on floating point types.
4060	bool isFEnvAccessOn(const LangOptions &LO) const {
4061	return getFPFeaturesInEffect(LO).getAllowFEnvAccess();
4062	}
4063
4064	protected:
4065	BinaryOperator(const ASTContext &Ctx, Expr *lhs, Expr *rhs, Opcode opc,
4066	QualType ResTy, ExprValueKind VK, ExprObjectKind OK,
4067	SourceLocation opLoc, FPOptionsOverride FPFeatures,
4068	bool dead2);
4069
4070	/// Construct an empty BinaryOperator, SC is CompoundAssignOperator.
4071	BinaryOperator(StmtClass SC, EmptyShell Empty) : Expr(SC, Empty) {
4072	BinaryOperatorBits.Opc = BO_MulAssign;
4073	}
4074
4075	/// Return the size in bytes needed for the trailing objects.
4076	/// Used to allocate the right amount of storage.
4077	static unsigned sizeOfTrailingObjects(bool HasFPFeatures) {
4078	return HasFPFeatures * sizeof(FPOptionsOverride);
4079	}
4080	};
4081
4082	/// CompoundAssignOperator - For compound assignments (e.g. +=), we keep
4083	/// track of the type the operation is performed in. Due to the semantics of
4084	/// these operators, the operands are promoted, the arithmetic performed, an
4085	/// implicit conversion back to the result type done, then the assignment takes
4086	/// place. This captures the intermediate type which the computation is done
4087	/// in.
4088	class CompoundAssignOperator : public BinaryOperator {
4089	QualType ComputationLHSType;
4090	QualType ComputationResultType;
4091
4092	/// Construct an empty CompoundAssignOperator.
4093	explicit CompoundAssignOperator(const ASTContext &C, EmptyShell Empty,
4094	bool hasFPFeatures)
4095	: BinaryOperator(CompoundAssignOperatorClass, Empty) {}
4096
4097	protected:
4098	CompoundAssignOperator(const ASTContext &C, Expr *lhs, Expr *rhs, Opcode opc,
4099	QualType ResType, ExprValueKind VK, ExprObjectKind OK,
4100	SourceLocation OpLoc, FPOptionsOverride FPFeatures,
4101	QualType CompLHSType, QualType CompResultType)
4102	: BinaryOperator(C, lhs, rhs, opc, ResType, VK, OK, OpLoc, FPFeatures,
4103	true),
4104	ComputationLHSType(CompLHSType), ComputationResultType(CompResultType) {
4105	assert(isCompoundAssignmentOp() &&
4106	"Only should be used for compound assignments");
4107	}
4108
4109	public:
4110	static CompoundAssignOperator *CreateEmpty(const ASTContext &C,
4111	bool hasFPFeatures);
4112
4113	static CompoundAssignOperator *
4114	Create(const ASTContext &C, Expr *lhs, Expr *rhs, Opcode opc, QualType ResTy,
4115	ExprValueKind VK, ExprObjectKind OK, SourceLocation opLoc,
4116	FPOptionsOverride FPFeatures, QualType CompLHSType = QualType(),
4117	QualType CompResultType = QualType());
4118
4119	// The two computation types are the type the LHS is converted
4120	// to for the computation and the type of the result; the two are
4121	// distinct in a few cases (specifically, int+=ptr and ptr-=ptr).
4122	QualType getComputationLHSType() const { return ComputationLHSType; }
4123	void setComputationLHSType(QualType T) { ComputationLHSType = T; }
4124
4125	QualType getComputationResultType() const { return ComputationResultType; }
4126	void setComputationResultType(QualType T) { ComputationResultType = T; }
4127
4128	static bool classof(const Stmt *S) {
4129	return S->getStmtClass() == CompoundAssignOperatorClass;
4130	}
4131	};
4132
4133	inline size_t BinaryOperator::offsetOfTrailingStorage() const {
4134	assert(BinaryOperatorBits.HasFPFeatures);
4135	return isa<CompoundAssignOperator>(Val: this) ? sizeof(CompoundAssignOperator)
4136	: sizeof(BinaryOperator);
4137	}
4138
4139	/// AbstractConditionalOperator - An abstract base class for
4140	/// ConditionalOperator and BinaryConditionalOperator.
4141	class AbstractConditionalOperator : public Expr {
4142	SourceLocation QuestionLoc, ColonLoc;
4143	friend class ASTStmtReader;
4144
4145	protected:
4146	AbstractConditionalOperator(StmtClass SC, QualType T, ExprValueKind VK,
4147	ExprObjectKind OK, SourceLocation qloc,
4148	SourceLocation cloc)
4149	: Expr(SC, T, VK, OK), QuestionLoc(qloc), ColonLoc(cloc) {}
4150
4151	AbstractConditionalOperator(StmtClass SC, EmptyShell Empty)
4152	: Expr(SC, Empty) { }
4153
4154	public:
4155	/// getCond - Return the expression representing the condition for
4156	/// the ?: operator.
4157	Expr *getCond() const;
4158
4159	/// getTrueExpr - Return the subexpression representing the value of
4160	/// the expression if the condition evaluates to true.
4161	Expr *getTrueExpr() const;
4162
4163	/// getFalseExpr - Return the subexpression representing the value of
4164	/// the expression if the condition evaluates to false. This is
4165	/// the same as getRHS.
4166	Expr *getFalseExpr() const;
4167
4168	SourceLocation getQuestionLoc() const { return QuestionLoc; }
4169	SourceLocation getColonLoc() const { return ColonLoc; }
4170
4171	static bool classof(const Stmt *T) {
4172	return T->getStmtClass() == ConditionalOperatorClass ||
4173	T->getStmtClass() == BinaryConditionalOperatorClass;
4174	}
4175	};
4176
4177	/// ConditionalOperator - The ?: ternary operator. The GNU "missing
4178	/// middle" extension is a BinaryConditionalOperator.
4179	class ConditionalOperator : public AbstractConditionalOperator {
4180	enum { COND, LHS, RHS, END_EXPR };
4181	Stmt* SubExprs[END_EXPR]; // Left/Middle/Right hand sides.
4182
4183	friend class ASTStmtReader;
4184	public:
4185	ConditionalOperator(Expr *cond, SourceLocation QLoc, Expr *lhs,
4186	SourceLocation CLoc, Expr *rhs, QualType t,
4187	ExprValueKind VK, ExprObjectKind OK)
4188	: AbstractConditionalOperator(ConditionalOperatorClass, t, VK, OK, QLoc,
4189	CLoc) {
4190	SubExprs[COND] = cond;
4191	SubExprs[LHS] = lhs;
4192	SubExprs[RHS] = rhs;
4193	setDependence(computeDependence(E: this));
4194	}
4195
4196	/// Build an empty conditional operator.
4197	explicit ConditionalOperator(EmptyShell Empty)
4198	: AbstractConditionalOperator(ConditionalOperatorClass, Empty) { }
4199
4200	/// getCond - Return the expression representing the condition for
4201	/// the ?: operator.
4202	Expr *getCond() const { return cast<Expr>(Val: SubExprs[COND]); }
4203
4204	/// getTrueExpr - Return the subexpression representing the value of
4205	/// the expression if the condition evaluates to true.
4206	Expr *getTrueExpr() const { return cast<Expr>(Val: SubExprs[LHS]); }
4207
4208	/// getFalseExpr - Return the subexpression representing the value of
4209	/// the expression if the condition evaluates to false. This is
4210	/// the same as getRHS.
4211	Expr *getFalseExpr() const { return cast<Expr>(Val: SubExprs[RHS]); }
4212
4213	Expr *getLHS() const { return cast<Expr>(Val: SubExprs[LHS]); }
4214	Expr *getRHS() const { return cast<Expr>(Val: SubExprs[RHS]); }
4215
4216	SourceLocation getBeginLoc() const LLVM_READONLY {
4217	return getCond()->getBeginLoc();
4218	}
4219	SourceLocation getEndLoc() const LLVM_READONLY {
4220	return getRHS()->getEndLoc();
4221	}
4222
4223	static bool classof(const Stmt *T) {
4224	return T->getStmtClass() == ConditionalOperatorClass;
4225	}
4226
4227	// Iterators
4228	child_range children() {
4229	return child_range(&SubExprs[0], &SubExprs[0]+END_EXPR);
4230	}
4231	const_child_range children() const {
4232	return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
4233	}
4234	};
4235
4236	/// BinaryConditionalOperator - The GNU extension to the conditional
4237	/// operator which allows the middle operand to be omitted.
4238	///
4239	/// This is a different expression kind on the assumption that almost
4240	/// every client ends up needing to know that these are different.
4241	class BinaryConditionalOperator : public AbstractConditionalOperator {
4242	enum { COMMON, COND, LHS, RHS, NUM_SUBEXPRS };
4243
4244	/// - the common condition/left-hand-side expression, which will be
4245	/// evaluated as the opaque value
4246	/// - the condition, expressed in terms of the opaque value
4247	/// - the left-hand-side, expressed in terms of the opaque value
4248	/// - the right-hand-side
4249	Stmt *SubExprs[NUM_SUBEXPRS];
4250	OpaqueValueExpr *OpaqueValue;
4251
4252	friend class ASTStmtReader;
4253	public:
4254	BinaryConditionalOperator(Expr *common, OpaqueValueExpr *opaqueValue,
4255	Expr *cond, Expr *lhs, Expr *rhs,
4256	SourceLocation qloc, SourceLocation cloc,
4257	QualType t, ExprValueKind VK, ExprObjectKind OK)
4258	: AbstractConditionalOperator(BinaryConditionalOperatorClass, t, VK, OK,
4259	qloc, cloc),
4260	OpaqueValue(opaqueValue) {
4261	SubExprs[COMMON] = common;
4262	SubExprs[COND] = cond;
4263	SubExprs[LHS] = lhs;
4264	SubExprs[RHS] = rhs;
4265	assert(OpaqueValue->getSourceExpr() == common && "Wrong opaque value");
4266	setDependence(computeDependence(E: this));
4267	}
4268
4269	/// Build an empty conditional operator.
4270	explicit BinaryConditionalOperator(EmptyShell Empty)
4271	: AbstractConditionalOperator(BinaryConditionalOperatorClass, Empty) { }
4272
4273	/// getCommon - Return the common expression, written to the
4274	/// left of the condition. The opaque value will be bound to the
4275	/// result of this expression.
4276	Expr *getCommon() const { return cast<Expr>(Val: SubExprs[COMMON]); }
4277
4278	/// getOpaqueValue - Return the opaque value placeholder.
4279	OpaqueValueExpr *getOpaqueValue() const { return OpaqueValue; }
4280
4281	/// getCond - Return the condition expression; this is defined
4282	/// in terms of the opaque value.
4283	Expr *getCond() const { return cast<Expr>(Val: SubExprs[COND]); }
4284
4285	/// getTrueExpr - Return the subexpression which will be
4286	/// evaluated if the condition evaluates to true; this is defined
4287	/// in terms of the opaque value.
4288	Expr *getTrueExpr() const {
4289	return cast<Expr>(Val: SubExprs[LHS]);
4290	}
4291
4292	/// getFalseExpr - Return the subexpression which will be
4293	/// evaluated if the condnition evaluates to false; this is
4294	/// defined in terms of the opaque value.
4295	Expr *getFalseExpr() const {
4296	return cast<Expr>(Val: SubExprs[RHS]);
4297	}
4298
4299	SourceLocation getBeginLoc() const LLVM_READONLY {
4300	return getCommon()->getBeginLoc();
4301	}
4302	SourceLocation getEndLoc() const LLVM_READONLY {
4303	return getFalseExpr()->getEndLoc();
4304	}
4305
4306	static bool classof(const Stmt *T) {
4307	return T->getStmtClass() == BinaryConditionalOperatorClass;
4308	}
4309
4310	// Iterators
4311	child_range children() {
4312	return child_range(SubExprs, SubExprs + NUM_SUBEXPRS);
4313	}
4314	const_child_range children() const {
4315	return const_child_range(SubExprs, SubExprs + NUM_SUBEXPRS);
4316	}
4317	};
4318
4319	inline Expr *AbstractConditionalOperator::getCond() const {
4320	if (const ConditionalOperator *co = dyn_cast<ConditionalOperator>(Val: this))
4321	return co->getCond();
4322	return cast<BinaryConditionalOperator>(Val: this)->getCond();
4323	}
4324
4325	inline Expr *AbstractConditionalOperator::getTrueExpr() const {
4326	if (const ConditionalOperator *co = dyn_cast<ConditionalOperator>(Val: this))
4327	return co->getTrueExpr();
4328	return cast<BinaryConditionalOperator>(Val: this)->getTrueExpr();
4329	}
4330
4331	inline Expr *AbstractConditionalOperator::getFalseExpr() const {
4332	if (const ConditionalOperator *co = dyn_cast<ConditionalOperator>(Val: this))
4333	return co->getFalseExpr();
4334	return cast<BinaryConditionalOperator>(Val: this)->getFalseExpr();
4335	}
4336
4337	/// AddrLabelExpr - The GNU address of label extension, representing &&label.
4338	class AddrLabelExpr : public Expr {
4339	SourceLocation AmpAmpLoc, LabelLoc;
4340	LabelDecl *Label;
4341	public:
4342	AddrLabelExpr(SourceLocation AALoc, SourceLocation LLoc, LabelDecl *L,
4343	QualType t)
4344	: Expr(AddrLabelExprClass, t, VK_PRValue, OK_Ordinary), AmpAmpLoc(AALoc),
4345	LabelLoc(LLoc), Label(L) {
4346	setDependence(ExprDependence::None);
4347	}
4348
4349	/// Build an empty address of a label expression.
4350	explicit AddrLabelExpr(EmptyShell Empty)
4351	: Expr(AddrLabelExprClass, Empty) { }
4352
4353	SourceLocation getAmpAmpLoc() const { return AmpAmpLoc; }
4354	void setAmpAmpLoc(SourceLocation L) { AmpAmpLoc = L; }
4355	SourceLocation getLabelLoc() const { return LabelLoc; }
4356	void setLabelLoc(SourceLocation L) { LabelLoc = L; }
4357
4358	SourceLocation getBeginLoc() const LLVM_READONLY { return AmpAmpLoc; }
4359	SourceLocation getEndLoc() const LLVM_READONLY { return LabelLoc; }
4360
4361	LabelDecl *getLabel() const { return Label; }
4362	void setLabel(LabelDecl *L) { Label = L; }
4363
4364	static bool classof(const Stmt *T) {
4365	return T->getStmtClass() == AddrLabelExprClass;
4366	}
4367
4368	// Iterators
4369	child_range children() {
4370	return child_range(child_iterator(), child_iterator());
4371	}
4372	const_child_range children() const {
4373	return const_child_range(const_child_iterator(), const_child_iterator());
4374	}
4375	};
4376
4377	/// StmtExpr - This is the GNU Statement Expression extension: ({int X=4; X;}).
4378	/// The StmtExpr contains a single CompoundStmt node, which it evaluates and
4379	/// takes the value of the last subexpression.
4380	///
4381	/// A StmtExpr is always an r-value; values "returned" out of a
4382	/// StmtExpr will be copied.
4383	class StmtExpr : public Expr {
4384	Stmt *SubStmt;
4385	SourceLocation LParenLoc, RParenLoc;
4386	public:
4387	StmtExpr(CompoundStmt *SubStmt, QualType T, SourceLocation LParenLoc,
4388	SourceLocation RParenLoc, unsigned TemplateDepth)
4389	: Expr(StmtExprClass, T, VK_PRValue, OK_Ordinary), SubStmt(SubStmt),
4390	LParenLoc(LParenLoc), RParenLoc(RParenLoc) {
4391	setDependence(computeDependence(E: this, TemplateDepth));
4392	// FIXME: A templated statement expression should have an associated
4393	// DeclContext so that nested declarations always have a dependent context.
4394	StmtExprBits.TemplateDepth = TemplateDepth;
4395	}
4396
4397	/// Build an empty statement expression.
4398	explicit StmtExpr(EmptyShell Empty) : Expr(StmtExprClass, Empty) { }
4399
4400	CompoundStmt *getSubStmt() { return cast<CompoundStmt>(Val: SubStmt); }
4401	const CompoundStmt *getSubStmt() const { return cast<CompoundStmt>(Val: SubStmt); }
4402	void setSubStmt(CompoundStmt *S) { SubStmt = S; }
4403
4404	SourceLocation getBeginLoc() const LLVM_READONLY { return LParenLoc; }
4405	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
4406
4407	SourceLocation getLParenLoc() const { return LParenLoc; }
4408	void setLParenLoc(SourceLocation L) { LParenLoc = L; }
4409	SourceLocation getRParenLoc() const { return RParenLoc; }
4410	void setRParenLoc(SourceLocation L) { RParenLoc = L; }
4411
4412	unsigned getTemplateDepth() const { return StmtExprBits.TemplateDepth; }
4413
4414	static bool classof(const Stmt *T) {
4415	return T->getStmtClass() == StmtExprClass;
4416	}
4417
4418	// Iterators
4419	child_range children() { return child_range(&SubStmt, &SubStmt+1); }
4420	const_child_range children() const {
4421	return const_child_range(&SubStmt, &SubStmt + 1);
4422	}
4423	};
4424
4425	/// ShuffleVectorExpr - clang-specific builtin-in function
4426	/// __builtin_shufflevector.
4427	/// This AST node represents a operator that does a constant
4428	/// shuffle, similar to LLVM's shufflevector instruction. It takes
4429	/// two vectors and a variable number of constant indices,
4430	/// and returns the appropriately shuffled vector.
4431	class ShuffleVectorExpr : public Expr {
4432	SourceLocation BuiltinLoc, RParenLoc;
4433
4434	// SubExprs - the list of values passed to the __builtin_shufflevector
4435	// function. The first two are vectors, and the rest are constant
4436	// indices. The number of values in this list is always
4437	// 2+the number of indices in the vector type.
4438	Stmt **SubExprs;
4439	unsigned NumExprs;
4440
4441	public:
4442	ShuffleVectorExpr(const ASTContext &C, ArrayRef<Expr*> args, QualType Type,
4443	SourceLocation BLoc, SourceLocation RP);
4444
4445	/// Build an empty vector-shuffle expression.
4446	explicit ShuffleVectorExpr(EmptyShell Empty)
4447	: Expr(ShuffleVectorExprClass, Empty), SubExprs(nullptr) { }
4448
4449	SourceLocation getBuiltinLoc() const { return BuiltinLoc; }
4450	void setBuiltinLoc(SourceLocation L) { BuiltinLoc = L; }
4451
4452	SourceLocation getRParenLoc() const { return RParenLoc; }
4453	void setRParenLoc(SourceLocation L) { RParenLoc = L; }
4454
4455	SourceLocation getBeginLoc() const LLVM_READONLY { return BuiltinLoc; }
4456	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
4457
4458	static bool classof(const Stmt *T) {
4459	return T->getStmtClass() == ShuffleVectorExprClass;
4460	}
4461
4462	/// getNumSubExprs - Return the size of the SubExprs array. This includes the
4463	/// constant expression, the actual arguments passed in, and the function
4464	/// pointers.
4465	unsigned getNumSubExprs() const { return NumExprs; }
4466
4467	/// Retrieve the array of expressions.
4468	Expr **getSubExprs() { return reinterpret_cast<Expr **>(SubExprs); }
4469
4470	/// getExpr - Return the Expr at the specified index.
4471	Expr *getExpr(unsigned Index) {
4472	assert((Index < NumExprs) && "Arg access out of range!");
4473	return cast<Expr>(Val: SubExprs[Index]);
4474	}
4475	const Expr *getExpr(unsigned Index) const {
4476	assert((Index < NumExprs) && "Arg access out of range!");
4477	return cast<Expr>(Val: SubExprs[Index]);
4478	}
4479
4480	void setExprs(const ASTContext &C, ArrayRef<Expr *> Exprs);
4481
4482	llvm::APSInt getShuffleMaskIdx(const ASTContext &Ctx, unsigned N) const {
4483	assert((N < NumExprs - 2) && "Shuffle idx out of range!");
4484	return getExpr(Index: N+2)->EvaluateKnownConstInt(Ctx);
4485	}
4486
4487	// Iterators
4488	child_range children() {
4489	return child_range(&SubExprs[0], &SubExprs[0]+NumExprs);
4490	}
4491	const_child_range children() const {
4492	return const_child_range(&SubExprs[0], &SubExprs[0] + NumExprs);
4493	}
4494	};
4495
4496	/// ConvertVectorExpr - Clang builtin function __builtin_convertvector
4497	/// This AST node provides support for converting a vector type to another
4498	/// vector type of the same arity.
4499	class ConvertVectorExpr : public Expr {
4500	private:
4501	Stmt *SrcExpr;
4502	TypeSourceInfo *TInfo;
4503	SourceLocation BuiltinLoc, RParenLoc;
4504
4505	friend class ASTReader;
4506	friend class ASTStmtReader;
4507	explicit ConvertVectorExpr(EmptyShell Empty) : Expr(ConvertVectorExprClass, Empty) {}
4508
4509	public:
4510	ConvertVectorExpr(Expr *SrcExpr, TypeSourceInfo *TI, QualType DstType,
4511	ExprValueKind VK, ExprObjectKind OK,
4512	SourceLocation BuiltinLoc, SourceLocation RParenLoc)
4513	: Expr(ConvertVectorExprClass, DstType, VK, OK), SrcExpr(SrcExpr),
4514	TInfo(TI), BuiltinLoc(BuiltinLoc), RParenLoc(RParenLoc) {
4515	setDependence(computeDependence(E: this));
4516	}
4517
4518	/// getSrcExpr - Return the Expr to be converted.
4519	Expr *getSrcExpr() const { return cast<Expr>(Val: SrcExpr); }
4520
4521	/// getTypeSourceInfo - Return the destination type.
4522	TypeSourceInfo *getTypeSourceInfo() const {
4523	return TInfo;
4524	}
4525	void setTypeSourceInfo(TypeSourceInfo *ti) {
4526	TInfo = ti;
4527	}
4528
4529	/// getBuiltinLoc - Return the location of the __builtin_convertvector token.
4530	SourceLocation getBuiltinLoc() const { return BuiltinLoc; }
4531
4532	/// getRParenLoc - Return the location of final right parenthesis.
4533	SourceLocation getRParenLoc() const { return RParenLoc; }
4534
4535	SourceLocation getBeginLoc() const LLVM_READONLY { return BuiltinLoc; }
4536	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
4537
4538	static bool classof(const Stmt *T) {
4539	return T->getStmtClass() == ConvertVectorExprClass;
4540	}
4541
4542	// Iterators
4543	child_range children() { return child_range(&SrcExpr, &SrcExpr+1); }
4544	const_child_range children() const {
4545	return const_child_range(&SrcExpr, &SrcExpr + 1);
4546	}
4547	};
4548
4549	/// ChooseExpr - GNU builtin-in function __builtin_choose_expr.
4550	/// This AST node is similar to the conditional operator (?:) in C, with
4551	/// the following exceptions:
4552	/// - the test expression must be a integer constant expression.
4553	/// - the expression returned acts like the chosen subexpression in every
4554	/// visible way: the type is the same as that of the chosen subexpression,
4555	/// and all predicates (whether it's an l-value, whether it's an integer
4556	/// constant expression, etc.) return the same result as for the chosen
4557	/// sub-expression.
4558	class ChooseExpr : public Expr {
4559	enum { COND, LHS, RHS, END_EXPR };
4560	Stmt* SubExprs[END_EXPR]; // Left/Middle/Right hand sides.
4561	SourceLocation BuiltinLoc, RParenLoc;
4562	bool CondIsTrue;
4563	public:
4564	ChooseExpr(SourceLocation BLoc, Expr *cond, Expr *lhs, Expr *rhs, QualType t,
4565	ExprValueKind VK, ExprObjectKind OK, SourceLocation RP,
4566	bool condIsTrue)
4567	: Expr(ChooseExprClass, t, VK, OK), BuiltinLoc(BLoc), RParenLoc(RP),
4568	CondIsTrue(condIsTrue) {
4569	SubExprs[COND] = cond;
4570	SubExprs[LHS] = lhs;
4571	SubExprs[RHS] = rhs;
4572
4573	setDependence(computeDependence(E: this));
4574	}
4575
4576	/// Build an empty __builtin_choose_expr.
4577	explicit ChooseExpr(EmptyShell Empty) : Expr(ChooseExprClass, Empty) { }
4578
4579	/// isConditionTrue - Return whether the condition is true (i.e. not
4580	/// equal to zero).
4581	bool isConditionTrue() const {
4582	assert(!isConditionDependent() &&
4583	"Dependent condition isn't true or false");
4584	return CondIsTrue;
4585	}
4586	void setIsConditionTrue(bool isTrue) { CondIsTrue = isTrue; }
4587
4588	bool isConditionDependent() const {
4589	return getCond()->isTypeDependent() || getCond()->isValueDependent();
4590	}
4591
4592	/// getChosenSubExpr - Return the subexpression chosen according to the
4593	/// condition.
4594	Expr *getChosenSubExpr() const {
4595	return isConditionTrue() ? getLHS() : getRHS();
4596	}
4597
4598	Expr *getCond() const { return cast<Expr>(Val: SubExprs[COND]); }
4599	void setCond(Expr *E) { SubExprs[COND] = E; }
4600	Expr *getLHS() const { return cast<Expr>(Val: SubExprs[LHS]); }
4601	void setLHS(Expr *E) { SubExprs[LHS] = E; }
4602	Expr *getRHS() const { return cast<Expr>(Val: SubExprs[RHS]); }
4603	void setRHS(Expr *E) { SubExprs[RHS] = E; }
4604
4605	SourceLocation getBuiltinLoc() const { return BuiltinLoc; }
4606	void setBuiltinLoc(SourceLocation L) { BuiltinLoc = L; }
4607
4608	SourceLocation getRParenLoc() const { return RParenLoc; }
4609	void setRParenLoc(SourceLocation L) { RParenLoc = L; }
4610
4611	SourceLocation getBeginLoc() const LLVM_READONLY { return BuiltinLoc; }
4612	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
4613
4614	static bool classof(const Stmt *T) {
4615	return T->getStmtClass() == ChooseExprClass;
4616	}
4617
4618	// Iterators
4619	child_range children() {
4620	return child_range(&SubExprs[0], &SubExprs[0]+END_EXPR);
4621	}
4622	const_child_range children() const {
4623	return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
4624	}
4625	};
4626
4627	/// GNUNullExpr - Implements the GNU __null extension, which is a name
4628	/// for a null pointer constant that has integral type (e.g., int or
4629	/// long) and is the same size and alignment as a pointer. The __null
4630	/// extension is typically only used by system headers, which define
4631	/// NULL as __null in C++ rather than using 0 (which is an integer
4632	/// that may not match the size of a pointer).
4633	class GNUNullExpr : public Expr {
4634	/// TokenLoc - The location of the __null keyword.
4635	SourceLocation TokenLoc;
4636
4637	public:
4638	GNUNullExpr(QualType Ty, SourceLocation Loc)
4639	: Expr(GNUNullExprClass, Ty, VK_PRValue, OK_Ordinary), TokenLoc(Loc) {
4640	setDependence(ExprDependence::None);
4641	}
4642
4643	/// Build an empty GNU __null expression.
4644	explicit GNUNullExpr(EmptyShell Empty) : Expr(GNUNullExprClass, Empty) { }
4645
4646	/// getTokenLocation - The location of the __null token.
4647	SourceLocation getTokenLocation() const { return TokenLoc; }
4648	void setTokenLocation(SourceLocation L) { TokenLoc = L; }
4649
4650	SourceLocation getBeginLoc() const LLVM_READONLY { return TokenLoc; }
4651	SourceLocation getEndLoc() const LLVM_READONLY { return TokenLoc; }
4652
4653	static bool classof(const Stmt *T) {
4654	return T->getStmtClass() == GNUNullExprClass;
4655	}
4656
4657	// Iterators
4658	child_range children() {
4659	return child_range(child_iterator(), child_iterator());
4660	}
4661	const_child_range children() const {
4662	return const_child_range(const_child_iterator(), const_child_iterator());
4663	}
4664	};
4665
4666	/// Represents a call to the builtin function \c __builtin_va_arg.
4667	class VAArgExpr : public Expr {
4668	Stmt *Val;
4669	llvm::PointerIntPair<TypeSourceInfo *, 1, bool> TInfo;
4670	SourceLocation BuiltinLoc, RParenLoc;
4671	public:
4672	VAArgExpr(SourceLocation BLoc, Expr *e, TypeSourceInfo *TInfo,
4673	SourceLocation RPLoc, QualType t, bool IsMS)
4674	: Expr(VAArgExprClass, t, VK_PRValue, OK_Ordinary), Val(e),
4675	TInfo(TInfo, IsMS), BuiltinLoc(BLoc), RParenLoc(RPLoc) {
4676	setDependence(computeDependence(E: this));
4677	}
4678
4679	/// Create an empty __builtin_va_arg expression.
4680	explicit VAArgExpr(EmptyShell Empty)
4681	: Expr(VAArgExprClass, Empty), Val(nullptr), TInfo(nullptr, false) {}
4682
4683	const Expr *getSubExpr() const { return cast<Expr>(Val); }
4684	Expr *getSubExpr() { return cast<Expr>(Val); }
4685	void setSubExpr(Expr *E) { Val = E; }
4686
4687	/// Returns whether this is really a Win64 ABI va_arg expression.
4688	bool isMicrosoftABI() const { return TInfo.getInt(); }
4689	void setIsMicrosoftABI(bool IsMS) { TInfo.setInt(IsMS); }
4690
4691	TypeSourceInfo *getWrittenTypeInfo() const { return TInfo.getPointer(); }
4692	void setWrittenTypeInfo(TypeSourceInfo *TI) { TInfo.setPointer(TI); }
4693
4694	SourceLocation getBuiltinLoc() const { return BuiltinLoc; }
4695	void setBuiltinLoc(SourceLocation L) { BuiltinLoc = L; }
4696
4697	SourceLocation getRParenLoc() const { return RParenLoc; }
4698	void setRParenLoc(SourceLocation L) { RParenLoc = L; }
4699
4700	SourceLocation getBeginLoc() const LLVM_READONLY { return BuiltinLoc; }
4701	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
4702
4703	static bool classof(const Stmt *T) {
4704	return T->getStmtClass() == VAArgExprClass;
4705	}
4706
4707	// Iterators
4708	child_range children() { return child_range(&Val, &Val+1); }
4709	const_child_range children() const {
4710	return const_child_range(&Val, &Val + 1);
4711	}
4712	};
4713
4714	enum class SourceLocIdentKind {
4715	Function,
4716	FuncSig,
4717	File,
4718	FileName,
4719	Line,
4720	Column,
4721	SourceLocStruct
4722	};
4723
4724	/// Represents a function call to one of __builtin_LINE(), __builtin_COLUMN(),
4725	/// __builtin_FUNCTION(), __builtin_FUNCSIG(), __builtin_FILE(),
4726	/// __builtin_FILE_NAME() or __builtin_source_location().
4727	class SourceLocExpr final : public Expr {
4728	SourceLocation BuiltinLoc, RParenLoc;
4729	DeclContext *ParentContext;
4730
4731	public:
4732	SourceLocExpr(const ASTContext &Ctx, SourceLocIdentKind Type,
4733	QualType ResultTy, SourceLocation BLoc,
4734	SourceLocation RParenLoc, DeclContext *Context);
4735
4736	/// Build an empty call expression.
4737	explicit SourceLocExpr(EmptyShell Empty) : Expr(SourceLocExprClass, Empty) {}
4738
4739	/// Return the result of evaluating this SourceLocExpr in the specified
4740	/// (and possibly null) default argument or initialization context.
4741	APValue EvaluateInContext(const ASTContext &Ctx,
4742	const Expr *DefaultExpr) const;
4743
4744	/// Return a string representing the name of the specific builtin function.
4745	StringRef getBuiltinStr() const;
4746
4747	SourceLocIdentKind getIdentKind() const {
4748	return static_cast<SourceLocIdentKind>(SourceLocExprBits.Kind);
4749	}
4750
4751	bool isIntType() const {
4752	switch (getIdentKind()) {
4753	case SourceLocIdentKind::File:
4754	case SourceLocIdentKind::FileName:
4755	case SourceLocIdentKind::Function:
4756	case SourceLocIdentKind::FuncSig:
4757	case SourceLocIdentKind::SourceLocStruct:
4758	return false;
4759	case SourceLocIdentKind::Line:
4760	case SourceLocIdentKind::Column:
4761	return true;
4762	}
4763	llvm_unreachable("unknown source location expression kind");
4764	}
4765
4766	/// If the SourceLocExpr has been resolved return the subexpression
4767	/// representing the resolved value. Otherwise return null.
4768	const DeclContext *getParentContext() const { return ParentContext; }
4769	DeclContext *getParentContext() { return ParentContext; }
4770
4771	SourceLocation getLocation() const { return BuiltinLoc; }
4772	SourceLocation getBeginLoc() const { return BuiltinLoc; }
4773	SourceLocation getEndLoc() const { return RParenLoc; }
4774
4775	child_range children() {
4776	return child_range(child_iterator(), child_iterator());
4777	}
4778
4779	const_child_range children() const {
4780	return const_child_range(child_iterator(), child_iterator());
4781	}
4782
4783	static bool classof(const Stmt *T) {
4784	return T->getStmtClass() == SourceLocExprClass;
4785	}
4786
4787	static bool MayBeDependent(SourceLocIdentKind Kind) {
4788	switch (Kind) {
4789	case SourceLocIdentKind::Function:
4790	case SourceLocIdentKind::FuncSig:
4791	case SourceLocIdentKind::SourceLocStruct:
4792	return true;
4793	default:
4794	return false;
4795	}
4796	}
4797
4798	private:
4799	friend class ASTStmtReader;
4800	};
4801
4802	/// Describes an C or C++ initializer list.
4803	///
4804	/// InitListExpr describes an initializer list, which can be used to
4805	/// initialize objects of different types, including
4806	/// struct/class/union types, arrays, and vectors. For example:
4807	///
4808	/// @code
4809	/// struct foo x = { 1, { 2, 3 } };
4810	/// @endcode
4811	///
4812	/// Prior to semantic analysis, an initializer list will represent the
4813	/// initializer list as written by the user, but will have the
4814	/// placeholder type "void". This initializer list is called the
4815	/// syntactic form of the initializer, and may contain C99 designated
4816	/// initializers (represented as DesignatedInitExprs), initializations
4817	/// of subobject members without explicit braces, and so on. Clients
4818	/// interested in the original syntax of the initializer list should
4819	/// use the syntactic form of the initializer list.
4820	///
4821	/// After semantic analysis, the initializer list will represent the
4822	/// semantic form of the initializer, where the initializations of all
4823	/// subobjects are made explicit with nested InitListExpr nodes and
4824	/// C99 designators have been eliminated by placing the designated
4825	/// initializations into the subobject they initialize. Additionally,
4826	/// any "holes" in the initialization, where no initializer has been
4827	/// specified for a particular subobject, will be replaced with
4828	/// implicitly-generated ImplicitValueInitExpr expressions that
4829	/// value-initialize the subobjects. Note, however, that the
4830	/// initializer lists may still have fewer initializers than there are
4831	/// elements to initialize within the object.
4832	///
4833	/// After semantic analysis has completed, given an initializer list,
4834	/// method isSemanticForm() returns true if and only if this is the
4835	/// semantic form of the initializer list (note: the same AST node
4836	/// may at the same time be the syntactic form).
4837	/// Given the semantic form of the initializer list, one can retrieve
4838	/// the syntactic form of that initializer list (when different)
4839	/// using method getSyntacticForm(); the method returns null if applied
4840	/// to a initializer list which is already in syntactic form.
4841	/// Similarly, given the syntactic form (i.e., an initializer list such
4842	/// that isSemanticForm() returns false), one can retrieve the semantic
4843	/// form using method getSemanticForm().
4844	/// Since many initializer lists have the same syntactic and semantic forms,
4845	/// getSyntacticForm() may return NULL, indicating that the current
4846	/// semantic initializer list also serves as its syntactic form.
4847	class InitListExpr : public Expr {
4848	// FIXME: Eliminate this vector in favor of ASTContext allocation
4849	typedef ASTVector<Stmt *> InitExprsTy;
4850	InitExprsTy InitExprs;
4851	SourceLocation LBraceLoc, RBraceLoc;
4852
4853	/// The alternative form of the initializer list (if it exists).
4854	/// The int part of the pair stores whether this initializer list is
4855	/// in semantic form. If not null, the pointer points to:
4856	/// - the syntactic form, if this is in semantic form;
4857	/// - the semantic form, if this is in syntactic form.
4858	llvm::PointerIntPair<InitListExpr *, 1, bool> AltForm;
4859
4860	/// Either:
4861	/// If this initializer list initializes an array with more elements than
4862	/// there are initializers in the list, specifies an expression to be used
4863	/// for value initialization of the rest of the elements.
4864	/// Or
4865	/// If this initializer list initializes a union, specifies which
4866	/// field within the union will be initialized.
4867	llvm::PointerUnion<Expr *, FieldDecl *> ArrayFillerOrUnionFieldInit;
4868
4869	public:
4870	InitListExpr(const ASTContext &C, SourceLocation lbraceloc,
4871	ArrayRef<Expr*> initExprs, SourceLocation rbraceloc);
4872
4873	/// Build an empty initializer list.
4874	explicit InitListExpr(EmptyShell Empty)
4875	: Expr(InitListExprClass, Empty), AltForm(nullptr, true) { }
4876
4877	unsigned getNumInits() const { return InitExprs.size(); }
4878
4879	/// Retrieve the set of initializers.
4880	Expr **getInits() { return reinterpret_cast<Expr **>(InitExprs.data()); }
4881
4882	/// Retrieve the set of initializers.
4883	Expr * const *getInits() const {
4884	return reinterpret_cast<Expr * const *>(InitExprs.data());
4885	}
4886
4887	ArrayRef<Expr *> inits() { return llvm::ArrayRef(getInits(), getNumInits()); }
4888
4889	ArrayRef<Expr *> inits() const {
4890	return llvm::ArrayRef(getInits(), getNumInits());
4891	}
4892
4893	const Expr *getInit(unsigned Init) const {
4894	assert(Init < getNumInits() && "Initializer access out of range!");
4895	return cast_or_null<Expr>(Val: InitExprs[Init]);
4896	}
4897
4898	Expr *getInit(unsigned Init) {
4899	assert(Init < getNumInits() && "Initializer access out of range!");
4900	return cast_or_null<Expr>(Val: InitExprs[Init]);
4901	}
4902
4903	void setInit(unsigned Init, Expr *expr) {
4904	assert(Init < getNumInits() && "Initializer access out of range!");
4905	InitExprs[Init] = expr;
4906
4907	if (expr)
4908	setDependence(getDependence() | expr->getDependence());
4909	}
4910
4911	/// Mark the semantic form of the InitListExpr as error when the semantic
4912	/// analysis fails.
4913	void markError() {
4914	assert(isSemanticForm());
4915	setDependence(getDependence() | ExprDependence::ErrorDependent);
4916	}
4917
4918	/// Reserve space for some number of initializers.
4919	void reserveInits(const ASTContext &C, unsigned NumInits);
4920
4921	/// Specify the number of initializers
4922	///
4923	/// If there are more than @p NumInits initializers, the remaining
4924	/// initializers will be destroyed. If there are fewer than @p
4925	/// NumInits initializers, NULL expressions will be added for the
4926	/// unknown initializers.
4927	void resizeInits(const ASTContext &Context, unsigned NumInits);
4928
4929	/// Updates the initializer at index @p Init with the new
4930	/// expression @p expr, and returns the old expression at that
4931	/// location.
4932	///
4933	/// When @p Init is out of range for this initializer list, the
4934	/// initializer list will be extended with NULL expressions to
4935	/// accommodate the new entry.
4936	Expr *updateInit(const ASTContext &C, unsigned Init, Expr *expr);
4937
4938	/// If this initializer list initializes an array with more elements
4939	/// than there are initializers in the list, specifies an expression to be
4940	/// used for value initialization of the rest of the elements.
4941	Expr *getArrayFiller() {
4942	return ArrayFillerOrUnionFieldInit.dyn_cast<Expr *>();
4943	}
4944	const Expr *getArrayFiller() const {
4945	return const_cast<InitListExpr *>(this)->getArrayFiller();
4946	}
4947	void setArrayFiller(Expr *filler);
4948
4949	/// Return true if this is an array initializer and its array "filler"
4950	/// has been set.
4951	bool hasArrayFiller() const { return getArrayFiller(); }
4952
4953	/// Determine whether this initializer list contains a designated initializer.
4954	bool hasDesignatedInit() const {
4955	return std::any_of(first: begin(), last: end(), pred: [](const Stmt *S) {
4956	return isa<DesignatedInitExpr>(Val: S);
4957	});
4958	}
4959
4960	/// If this initializes a union, specifies which field in the
4961	/// union to initialize.
4962	///
4963	/// Typically, this field is the first named field within the
4964	/// union. However, a designated initializer can specify the
4965	/// initialization of a different field within the union.
4966	FieldDecl *getInitializedFieldInUnion() {
4967	return ArrayFillerOrUnionFieldInit.dyn_cast<FieldDecl *>();
4968	}
4969	const FieldDecl *getInitializedFieldInUnion() const {
4970	return const_cast<InitListExpr *>(this)->getInitializedFieldInUnion();
4971	}
4972	void setInitializedFieldInUnion(FieldDecl *FD) {
4973	assert((FD == nullptr
4974	|| getInitializedFieldInUnion() == nullptr
4975	|| getInitializedFieldInUnion() == FD)
4976	&& "Only one field of a union may be initialized at a time!");
4977	ArrayFillerOrUnionFieldInit = FD;
4978	}
4979
4980	// Explicit InitListExpr's originate from source code (and have valid source
4981	// locations). Implicit InitListExpr's are created by the semantic analyzer.
4982	// FIXME: This is wrong; InitListExprs created by semantic analysis have
4983	// valid source locations too!
4984	bool isExplicit() const {
4985	return LBraceLoc.isValid() && RBraceLoc.isValid();
4986	}
4987
4988	/// Is this an initializer for an array of characters, initialized by a string
4989	/// literal or an @encode?
4990	bool isStringLiteralInit() const;
4991
4992	/// Is this a transparent initializer list (that is, an InitListExpr that is
4993	/// purely syntactic, and whose semantics are that of the sole contained
4994	/// initializer)?
4995	bool isTransparent() const;
4996
4997	/// Is this the zero initializer {0} in a language which considers it
4998	/// idiomatic?
4999	bool isIdiomaticZeroInitializer(const LangOptions &LangOpts) const;
5000
5001	SourceLocation getLBraceLoc() const { return LBraceLoc; }
5002	void setLBraceLoc(SourceLocation Loc) { LBraceLoc = Loc; }
5003	SourceLocation getRBraceLoc() const { return RBraceLoc; }
5004	void setRBraceLoc(SourceLocation Loc) { RBraceLoc = Loc; }
5005
5006	bool isSemanticForm() const { return AltForm.getInt(); }
5007	InitListExpr *getSemanticForm() const {
5008	return isSemanticForm() ? nullptr : AltForm.getPointer();
5009	}
5010	bool isSyntacticForm() const {
5011	return !AltForm.getInt() || !AltForm.getPointer();
5012	}
5013	InitListExpr *getSyntacticForm() const {
5014	return isSemanticForm() ? AltForm.getPointer() : nullptr;
5015	}
5016
5017	void setSyntacticForm(InitListExpr *Init) {
5018	AltForm.setPointer(Init);
5019	AltForm.setInt(true);
5020	Init->AltForm.setPointer(this);
5021	Init->AltForm.setInt(false);
5022	}
5023
5024	bool hadArrayRangeDesignator() const {
5025	return InitListExprBits.HadArrayRangeDesignator != 0;
5026	}
5027	void sawArrayRangeDesignator(bool ARD = true) {
5028	InitListExprBits.HadArrayRangeDesignator = ARD;
5029	}
5030
5031	SourceLocation getBeginLoc() const LLVM_READONLY;
5032	SourceLocation getEndLoc() const LLVM_READONLY;
5033
5034	static bool classof(const Stmt *T) {
5035	return T->getStmtClass() == InitListExprClass;
5036	}
5037
5038	// Iterators
5039	child_range children() {
5040	const_child_range CCR = const_cast<const InitListExpr *>(this)->children();
5041	return child_range(cast_away_const(RHS: CCR.begin()),
5042	cast_away_const(RHS: CCR.end()));
5043	}
5044
5045	const_child_range children() const {
5046	// FIXME: This does not include the array filler expression.
5047	if (InitExprs.empty())
5048	return const_child_range(const_child_iterator(), const_child_iterator());
5049	return const_child_range(&InitExprs[0], &InitExprs[0] + InitExprs.size());
5050	}
5051
5052	typedef InitExprsTy::iterator iterator;
5053	typedef InitExprsTy::const_iterator const_iterator;
5054	typedef InitExprsTy::reverse_iterator reverse_iterator;
5055	typedef InitExprsTy::const_reverse_iterator const_reverse_iterator;
5056
5057	iterator begin() { return InitExprs.begin(); }
5058	const_iterator begin() const { return InitExprs.begin(); }
5059	iterator end() { return InitExprs.end(); }
5060	const_iterator end() const { return InitExprs.end(); }
5061	reverse_iterator rbegin() { return InitExprs.rbegin(); }
5062	const_reverse_iterator rbegin() const { return InitExprs.rbegin(); }
5063	reverse_iterator rend() { return InitExprs.rend(); }
5064	const_reverse_iterator rend() const { return InitExprs.rend(); }
5065
5066	friend class ASTStmtReader;
5067	friend class ASTStmtWriter;
5068	};
5069
5070	/// Represents a C99 designated initializer expression.
5071	///
5072	/// A designated initializer expression (C99 6.7.8) contains one or
5073	/// more designators (which can be field designators, array
5074	/// designators, or GNU array-range designators) followed by an
5075	/// expression that initializes the field or element(s) that the
5076	/// designators refer to. For example, given:
5077	///
5078	/// @code
5079	/// struct point {
5080	/// double x;
5081	/// double y;
5082	/// };
5083	/// struct point ptarray[10] = { [2].y = 1.0, [2].x = 2.0, [0].x = 1.0 };
5084	/// @endcode
5085	///
5086	/// The InitListExpr contains three DesignatedInitExprs, the first of
5087	/// which covers @c [2].y=1.0. This DesignatedInitExpr will have two
5088	/// designators, one array designator for @c [2] followed by one field
5089	/// designator for @c .y. The initialization expression will be 1.0.
5090	class DesignatedInitExpr final
5091	: public Expr,
5092	private llvm::TrailingObjects<DesignatedInitExpr, Stmt *> {
5093	public:
5094	/// Forward declaration of the Designator class.
5095	class Designator;
5096
5097	private:
5098	/// The location of the '=' or ':' prior to the actual initializer
5099	/// expression.
5100	SourceLocation EqualOrColonLoc;
5101
5102	/// Whether this designated initializer used the GNU deprecated
5103	/// syntax rather than the C99 '=' syntax.
5104	LLVM_PREFERRED_TYPE(bool)
5105	unsigned GNUSyntax : 1;
5106
5107	/// The number of designators in this initializer expression.
5108	unsigned NumDesignators : 15;
5109
5110	/// The number of subexpressions of this initializer expression,
5111	/// which contains both the initializer and any additional
5112	/// expressions used by array and array-range designators.
5113	unsigned NumSubExprs : 16;
5114
5115	/// The designators in this designated initialization
5116	/// expression.
5117	Designator *Designators;
5118
5119	DesignatedInitExpr(const ASTContext &C, QualType Ty,
5120	llvm::ArrayRef<Designator> Designators,
5121	SourceLocation EqualOrColonLoc, bool GNUSyntax,
5122	ArrayRef<Expr *> IndexExprs, Expr *Init);
5123
5124	explicit DesignatedInitExpr(unsigned NumSubExprs)
5125	: Expr(DesignatedInitExprClass, EmptyShell()),
5126	NumDesignators(0), NumSubExprs(NumSubExprs), Designators(nullptr) { }
5127
5128	public:
5129	/// Represents a single C99 designator.
5130	///
5131	/// @todo This class is infuriatingly similar to clang::Designator,
5132	/// but minor differences (storing indices vs. storing pointers)
5133	/// keep us from reusing it. Try harder, later, to rectify these
5134	/// differences.
5135	class Designator {
5136	/// A field designator, e.g., ".x".
5137	struct FieldDesignatorInfo {
5138	/// Refers to the field that is being initialized. The low bit
5139	/// of this field determines whether this is actually a pointer
5140	/// to an IdentifierInfo (if 1) or a FieldDecl (if 0). When
5141	/// initially constructed, a field designator will store an
5142	/// IdentifierInfo*. After semantic analysis has resolved that
5143	/// name, the field designator will instead store a FieldDecl*.
5144	uintptr_t NameOrField;
5145
5146	/// The location of the '.' in the designated initializer.
5147	SourceLocation DotLoc;
5148
5149	/// The location of the field name in the designated initializer.
5150	SourceLocation FieldLoc;
5151
5152	FieldDesignatorInfo(const IdentifierInfo *II, SourceLocation DotLoc,
5153	SourceLocation FieldLoc)
5154	: NameOrField(reinterpret_cast<uintptr_t>(II) | 0x1), DotLoc(DotLoc),
5155	FieldLoc(FieldLoc) {}
5156	};
5157
5158	/// An array or GNU array-range designator, e.g., "[9]" or "[10...15]".
5159	struct ArrayOrRangeDesignatorInfo {
5160	/// Location of the first index expression within the designated
5161	/// initializer expression's list of subexpressions.
5162	unsigned Index;
5163
5164	/// The location of the '[' starting the array range designator.
5165	SourceLocation LBracketLoc;
5166
5167	/// The location of the ellipsis separating the start and end
5168	/// indices. Only valid for GNU array-range designators.
5169	SourceLocation EllipsisLoc;
5170
5171	/// The location of the ']' terminating the array range designator.
5172	SourceLocation RBracketLoc;
5173
5174	ArrayOrRangeDesignatorInfo(unsigned Index, SourceLocation LBracketLoc,
5175	SourceLocation RBracketLoc)
5176	: Index(Index), LBracketLoc(LBracketLoc), RBracketLoc(RBracketLoc) {}
5177
5178	ArrayOrRangeDesignatorInfo(unsigned Index,
5179	SourceLocation LBracketLoc,
5180	SourceLocation EllipsisLoc,
5181	SourceLocation RBracketLoc)
5182	: Index(Index), LBracketLoc(LBracketLoc), EllipsisLoc(EllipsisLoc),
5183	RBracketLoc(RBracketLoc) {}
5184	};
5185
5186	/// The kind of designator this describes.
5187	enum DesignatorKind {
5188	FieldDesignator,
5189	ArrayDesignator,
5190	ArrayRangeDesignator
5191	};
5192
5193	DesignatorKind Kind;
5194
5195	union {
5196	/// A field designator, e.g., ".x".
5197	struct FieldDesignatorInfo FieldInfo;
5198
5199	/// An array or GNU array-range designator, e.g., "[9]" or "[10..15]".
5200	struct ArrayOrRangeDesignatorInfo ArrayOrRangeInfo;
5201	};
5202
5203	Designator(DesignatorKind Kind) : Kind(Kind) {}
5204
5205	public:
5206	Designator() {}
5207
5208	bool isFieldDesignator() const { return Kind == FieldDesignator; }
5209	bool isArrayDesignator() const { return Kind == ArrayDesignator; }
5210	bool isArrayRangeDesignator() const { return Kind == ArrayRangeDesignator; }
5211
5212	//===------------------------------------------------------------------===//
5213	// FieldDesignatorInfo
5214
5215	/// Creates a field designator.
5216	static Designator CreateFieldDesignator(const IdentifierInfo *FieldName,
5217	SourceLocation DotLoc,
5218	SourceLocation FieldLoc) {
5219	Designator D(FieldDesignator);
5220	new (&D.FieldInfo) FieldDesignatorInfo(FieldName, DotLoc, FieldLoc);
5221	return D;
5222	}
5223
5224	const IdentifierInfo *getFieldName() const;
5225
5226	FieldDecl *getFieldDecl() const {
5227	assert(isFieldDesignator() && "Only valid on a field designator");
5228	if (FieldInfo.NameOrField & 0x01)
5229	return nullptr;
5230	return reinterpret_cast<FieldDecl *>(FieldInfo.NameOrField);
5231	}
5232
5233	void setFieldDecl(FieldDecl *FD) {
5234	assert(isFieldDesignator() && "Only valid on a field designator");
5235	FieldInfo.NameOrField = reinterpret_cast<uintptr_t>(FD);
5236	}
5237
5238	SourceLocation getDotLoc() const {
5239	assert(isFieldDesignator() && "Only valid on a field designator");
5240	return FieldInfo.DotLoc;
5241	}
5242
5243	SourceLocation getFieldLoc() const {
5244	assert(isFieldDesignator() && "Only valid on a field designator");
5245	return FieldInfo.FieldLoc;
5246	}
5247
5248	//===------------------------------------------------------------------===//
5249	// ArrayOrRangeDesignator
5250
5251	/// Creates an array designator.
5252	static Designator CreateArrayDesignator(unsigned Index,
5253	SourceLocation LBracketLoc,
5254	SourceLocation RBracketLoc) {
5255	Designator D(ArrayDesignator);
5256	new (&D.ArrayOrRangeInfo) ArrayOrRangeDesignatorInfo(Index, LBracketLoc,
5257	RBracketLoc);
5258	return D;
5259	}
5260
5261	/// Creates a GNU array-range designator.
5262	static Designator CreateArrayRangeDesignator(unsigned Index,
5263	SourceLocation LBracketLoc,
5264	SourceLocation EllipsisLoc,
5265	SourceLocation RBracketLoc) {
5266	Designator D(ArrayRangeDesignator);
5267	new (&D.ArrayOrRangeInfo) ArrayOrRangeDesignatorInfo(Index, LBracketLoc,
5268	EllipsisLoc,
5269	RBracketLoc);
5270	return D;
5271	}
5272
5273	unsigned getArrayIndex() const {
5274	assert((isArrayDesignator() || isArrayRangeDesignator()) &&
5275	"Only valid on an array or array-range designator");
5276	return ArrayOrRangeInfo.Index;
5277	}
5278
5279	SourceLocation getLBracketLoc() const {
5280	assert((isArrayDesignator() || isArrayRangeDesignator()) &&
5281	"Only valid on an array or array-range designator");
5282	return ArrayOrRangeInfo.LBracketLoc;
5283	}
5284
5285	SourceLocation getEllipsisLoc() const {
5286	assert(isArrayRangeDesignator() &&
5287	"Only valid on an array-range designator");
5288	return ArrayOrRangeInfo.EllipsisLoc;
5289	}
5290
5291	SourceLocation getRBracketLoc() const {
5292	assert((isArrayDesignator() || isArrayRangeDesignator()) &&
5293	"Only valid on an array or array-range designator");
5294	return ArrayOrRangeInfo.RBracketLoc;
5295	}
5296
5297	SourceLocation getBeginLoc() const LLVM_READONLY {
5298	if (isFieldDesignator())
5299	return getDotLoc().isInvalid() ? getFieldLoc() : getDotLoc();
5300	return getLBracketLoc();
5301	}
5302
5303	SourceLocation getEndLoc() const LLVM_READONLY {
5304	return isFieldDesignator() ? getFieldLoc() : getRBracketLoc();
5305	}
5306
5307	SourceRange getSourceRange() const LLVM_READONLY {
5308	return SourceRange(getBeginLoc(), getEndLoc());
5309	}
5310	};
5311
5312	static DesignatedInitExpr *Create(const ASTContext &C,
5313	llvm::ArrayRef<Designator> Designators,
5314	ArrayRef<Expr*> IndexExprs,
5315	SourceLocation EqualOrColonLoc,
5316	bool GNUSyntax, Expr *Init);
5317
5318	static DesignatedInitExpr *CreateEmpty(const ASTContext &C,
5319	unsigned NumIndexExprs);
5320
5321	/// Returns the number of designators in this initializer.
5322	unsigned size() const { return NumDesignators; }
5323
5324	// Iterator access to the designators.
5325	llvm::MutableArrayRef<Designator> designators() {
5326	return {Designators, NumDesignators};
5327	}
5328
5329	llvm::ArrayRef<Designator> designators() const {
5330	return {Designators, NumDesignators};
5331	}
5332
5333	Designator *getDesignator(unsigned Idx) { return &designators()[Idx]; }
5334	const Designator *getDesignator(unsigned Idx) const {
5335	return &designators()[Idx];
5336	}
5337
5338	void setDesignators(const ASTContext &C, const Designator *Desigs,
5339	unsigned NumDesigs);
5340
5341	Expr *getArrayIndex(const Designator &D) const;
5342	Expr *getArrayRangeStart(const Designator &D) const;
5343	Expr *getArrayRangeEnd(const Designator &D) const;
5344
5345	/// Retrieve the location of the '=' that precedes the
5346	/// initializer value itself, if present.
5347	SourceLocation getEqualOrColonLoc() const { return EqualOrColonLoc; }
5348	void setEqualOrColonLoc(SourceLocation L) { EqualOrColonLoc = L; }
5349
5350	/// Whether this designated initializer should result in direct-initialization
5351	/// of the designated subobject (eg, '{.foo{1, 2, 3}}').
5352	bool isDirectInit() const { return EqualOrColonLoc.isInvalid(); }
5353
5354	/// Determines whether this designated initializer used the
5355	/// deprecated GNU syntax for designated initializers.
5356	bool usesGNUSyntax() const { return GNUSyntax; }
5357	void setGNUSyntax(bool GNU) { GNUSyntax = GNU; }
5358
5359	/// Retrieve the initializer value.
5360	Expr *getInit() const {
5361	return cast<Expr>(*const_cast<DesignatedInitExpr*>(this)->child_begin());
5362	}
5363
5364	void setInit(Expr *init) {
5365	*child_begin() = init;
5366	}
5367
5368	/// Retrieve the total number of subexpressions in this
5369	/// designated initializer expression, including the actual
5370	/// initialized value and any expressions that occur within array
5371	/// and array-range designators.
5372	unsigned getNumSubExprs() const { return NumSubExprs; }
5373
5374	Expr *getSubExpr(unsigned Idx) const {
5375	assert(Idx < NumSubExprs && "Subscript out of range");
5376	return cast<Expr>(getTrailingObjects<Stmt *>()[Idx]);
5377	}
5378
5379	void setSubExpr(unsigned Idx, Expr *E) {
5380	assert(Idx < NumSubExprs && "Subscript out of range");
5381	getTrailingObjects<Stmt *>()[Idx] = E;
5382	}
5383
5384	/// Replaces the designator at index @p Idx with the series
5385	/// of designators in [First, Last).
5386	void ExpandDesignator(const ASTContext &C, unsigned Idx,
5387	const Designator *First, const Designator *Last);
5388
5389	SourceRange getDesignatorsSourceRange() const;
5390
5391	SourceLocation getBeginLoc() const LLVM_READONLY;
5392	SourceLocation getEndLoc() const LLVM_READONLY;
5393
5394	static bool classof(const Stmt *T) {
5395	return T->getStmtClass() == DesignatedInitExprClass;
5396	}
5397
5398	// Iterators
5399	child_range children() {
5400	Stmt **begin = getTrailingObjects<Stmt *>();
5401	return child_range(begin, begin + NumSubExprs);
5402	}
5403	const_child_range children() const {
5404	Stmt * const *begin = getTrailingObjects<Stmt *>();
5405	return const_child_range(begin, begin + NumSubExprs);
5406	}
5407
5408	friend TrailingObjects;
5409	};
5410
5411	/// Represents a place-holder for an object not to be initialized by
5412	/// anything.
5413	///
5414	/// This only makes sense when it appears as part of an updater of a
5415	/// DesignatedInitUpdateExpr (see below). The base expression of a DIUE
5416	/// initializes a big object, and the NoInitExpr's mark the spots within the
5417	/// big object not to be overwritten by the updater.
5418	///
5419	/// \see DesignatedInitUpdateExpr
5420	class NoInitExpr : public Expr {
5421	public:
5422	explicit NoInitExpr(QualType ty)
5423	: Expr(NoInitExprClass, ty, VK_PRValue, OK_Ordinary) {
5424	setDependence(computeDependence(E: this));
5425	}
5426
5427	explicit NoInitExpr(EmptyShell Empty)
5428	: Expr(NoInitExprClass, Empty) { }
5429
5430	static bool classof(const Stmt *T) {
5431	return T->getStmtClass() == NoInitExprClass;
5432	}
5433
5434	SourceLocation getBeginLoc() const LLVM_READONLY { return SourceLocation(); }
5435	SourceLocation getEndLoc() const LLVM_READONLY { return SourceLocation(); }
5436
5437	// Iterators
5438	child_range children() {
5439	return child_range(child_iterator(), child_iterator());
5440	}
5441	const_child_range children() const {
5442	return const_child_range(const_child_iterator(), const_child_iterator());
5443	}
5444	};
5445
5446	// In cases like:
5447	// struct Q { int a, b, c; };
5448	// Q *getQ();
5449	// void foo() {
5450	// struct A { Q q; } a = { *getQ(), .q.b = 3 };
5451	// }
5452	//
5453	// We will have an InitListExpr for a, with type A, and then a
5454	// DesignatedInitUpdateExpr for "a.q" with type Q. The "base" for this DIUE
5455	// is the call expression *getQ(); the "updater" for the DIUE is ".q.b = 3"
5456	//
5457	class DesignatedInitUpdateExpr : public Expr {
5458	// BaseAndUpdaterExprs[0] is the base expression;
5459	// BaseAndUpdaterExprs[1] is an InitListExpr overwriting part of the base.
5460	Stmt *BaseAndUpdaterExprs[2];
5461
5462	public:
5463	DesignatedInitUpdateExpr(const ASTContext &C, SourceLocation lBraceLoc,
5464	Expr *baseExprs, SourceLocation rBraceLoc);
5465
5466	explicit DesignatedInitUpdateExpr(EmptyShell Empty)
5467	: Expr(DesignatedInitUpdateExprClass, Empty) { }
5468
5469	SourceLocation getBeginLoc() const LLVM_READONLY;
5470	SourceLocation getEndLoc() const LLVM_READONLY;
5471
5472	static bool classof(const Stmt *T) {
5473	return T->getStmtClass() == DesignatedInitUpdateExprClass;
5474	}
5475
5476	Expr *getBase() const { return cast<Expr>(Val: BaseAndUpdaterExprs[0]); }
5477	void setBase(Expr *Base) { BaseAndUpdaterExprs[0] = Base; }
5478
5479	InitListExpr *getUpdater() const {
5480	return cast<InitListExpr>(Val: BaseAndUpdaterExprs[1]);
5481	}
5482	void setUpdater(Expr *Updater) { BaseAndUpdaterExprs[1] = Updater; }
5483
5484	// Iterators
5485	// children = the base and the updater
5486	child_range children() {
5487	return child_range(&BaseAndUpdaterExprs[0], &BaseAndUpdaterExprs[0] + 2);
5488	}
5489	const_child_range children() const {
5490	return const_child_range(&BaseAndUpdaterExprs[0],
5491	&BaseAndUpdaterExprs[0] + 2);
5492	}
5493	};
5494
5495	/// Represents a loop initializing the elements of an array.
5496	///
5497	/// The need to initialize the elements of an array occurs in a number of
5498	/// contexts:
5499	///
5500	/// * in the implicit copy/move constructor for a class with an array member
5501	/// * when a lambda-expression captures an array by value
5502	/// * when a decomposition declaration decomposes an array
5503	///
5504	/// There are two subexpressions: a common expression (the source array)
5505	/// that is evaluated once up-front, and a per-element initializer that
5506	/// runs once for each array element.
5507	///
5508	/// Within the per-element initializer, the common expression may be referenced
5509	/// via an OpaqueValueExpr, and the current index may be obtained via an
5510	/// ArrayInitIndexExpr.
5511	class ArrayInitLoopExpr : public Expr {
5512	Stmt *SubExprs[2];
5513
5514	explicit ArrayInitLoopExpr(EmptyShell Empty)
5515	: Expr(ArrayInitLoopExprClass, Empty), SubExprs{} {}
5516
5517	public:
5518	explicit ArrayInitLoopExpr(QualType T, Expr *CommonInit, Expr *ElementInit)
5519	: Expr(ArrayInitLoopExprClass, T, VK_PRValue, OK_Ordinary),
5520	SubExprs{CommonInit, ElementInit} {
5521	setDependence(computeDependence(E: this));
5522	}
5523
5524	/// Get the common subexpression shared by all initializations (the source
5525	/// array).
5526	OpaqueValueExpr *getCommonExpr() const {
5527	return cast<OpaqueValueExpr>(Val: SubExprs[0]);
5528	}
5529
5530	/// Get the initializer to use for each array element.
5531	Expr *getSubExpr() const { return cast<Expr>(Val: SubExprs[1]); }
5532
5533	llvm::APInt getArraySize() const {
5534	return cast<ConstantArrayType>(getType()->castAsArrayTypeUnsafe())
5535	->getSize();
5536	}
5537
5538	static bool classof(const Stmt *S) {
5539	return S->getStmtClass() == ArrayInitLoopExprClass;
5540	}
5541
5542	SourceLocation getBeginLoc() const LLVM_READONLY {
5543	return getCommonExpr()->getBeginLoc();
5544	}
5545	SourceLocation getEndLoc() const LLVM_READONLY {
5546	return getCommonExpr()->getEndLoc();
5547	}
5548
5549	child_range children() {
5550	return child_range(SubExprs, SubExprs + 2);
5551	}
5552	const_child_range children() const {
5553	return const_child_range(SubExprs, SubExprs + 2);
5554	}
5555
5556	friend class ASTReader;
5557	friend class ASTStmtReader;
5558	friend class ASTStmtWriter;
5559	};
5560
5561	/// Represents the index of the current element of an array being
5562	/// initialized by an ArrayInitLoopExpr. This can only appear within the
5563	/// subexpression of an ArrayInitLoopExpr.
5564	class ArrayInitIndexExpr : public Expr {
5565	explicit ArrayInitIndexExpr(EmptyShell Empty)
5566	: Expr(ArrayInitIndexExprClass, Empty) {}
5567
5568	public:
5569	explicit ArrayInitIndexExpr(QualType T)
5570	: Expr(ArrayInitIndexExprClass, T, VK_PRValue, OK_Ordinary) {
5571	setDependence(ExprDependence::None);
5572	}
5573
5574	static bool classof(const Stmt *S) {
5575	return S->getStmtClass() == ArrayInitIndexExprClass;
5576	}
5577
5578	SourceLocation getBeginLoc() const LLVM_READONLY { return SourceLocation(); }
5579	SourceLocation getEndLoc() const LLVM_READONLY { return SourceLocation(); }
5580
5581	child_range children() {
5582	return child_range(child_iterator(), child_iterator());
5583	}
5584	const_child_range children() const {
5585	return const_child_range(const_child_iterator(), const_child_iterator());
5586	}
5587
5588	friend class ASTReader;
5589	friend class ASTStmtReader;
5590	};
5591
5592	/// Represents an implicitly-generated value initialization of
5593	/// an object of a given type.
5594	///
5595	/// Implicit value initializations occur within semantic initializer
5596	/// list expressions (InitListExpr) as placeholders for subobject
5597	/// initializations not explicitly specified by the user.
5598	///
5599	/// \see InitListExpr
5600	class ImplicitValueInitExpr : public Expr {
5601	public:
5602	explicit ImplicitValueInitExpr(QualType ty)
5603	: Expr(ImplicitValueInitExprClass, ty, VK_PRValue, OK_Ordinary) {
5604	setDependence(computeDependence(E: this));
5605	}
5606
5607	/// Construct an empty implicit value initialization.
5608	explicit ImplicitValueInitExpr(EmptyShell Empty)
5609	: Expr(ImplicitValueInitExprClass, Empty) { }
5610
5611	static bool classof(const Stmt *T) {
5612	return T->getStmtClass() == ImplicitValueInitExprClass;
5613	}
5614
5615	SourceLocation getBeginLoc() const LLVM_READONLY { return SourceLocation(); }
5616	SourceLocation getEndLoc() const LLVM_READONLY { return SourceLocation(); }
5617
5618	// Iterators
5619	child_range children() {
5620	return child_range(child_iterator(), child_iterator());
5621	}
5622	const_child_range children() const {
5623	return const_child_range(const_child_iterator(), const_child_iterator());
5624	}
5625	};
5626
5627	class ParenListExpr final
5628	: public Expr,
5629	private llvm::TrailingObjects<ParenListExpr, Stmt *> {
5630	friend class ASTStmtReader;
5631	friend TrailingObjects;
5632
5633	/// The location of the left and right parentheses.
5634	SourceLocation LParenLoc, RParenLoc;
5635
5636	/// Build a paren list.
5637	ParenListExpr(SourceLocation LParenLoc, ArrayRef<Expr *> Exprs,
5638	SourceLocation RParenLoc);
5639
5640	/// Build an empty paren list.
5641	ParenListExpr(EmptyShell Empty, unsigned NumExprs);
5642
5643	public:
5644	/// Create a paren list.
5645	static ParenListExpr *Create(const ASTContext &Ctx, SourceLocation LParenLoc,
5646	ArrayRef<Expr *> Exprs,
5647	SourceLocation RParenLoc);
5648
5649	/// Create an empty paren list.
5650	static ParenListExpr *CreateEmpty(const ASTContext &Ctx, unsigned NumExprs);
5651
5652	/// Return the number of expressions in this paren list.
5653	unsigned getNumExprs() const { return ParenListExprBits.NumExprs; }
5654
5655	Expr *getExpr(unsigned Init) {
5656	assert(Init < getNumExprs() && "Initializer access out of range!");
5657	return getExprs()[Init];
5658	}
5659
5660	const Expr *getExpr(unsigned Init) const {
5661	return const_cast<ParenListExpr *>(this)->getExpr(Init);
5662	}
5663
5664	Expr **getExprs() {
5665	return reinterpret_cast<Expr **>(getTrailingObjects<Stmt *>());
5666	}
5667
5668	ArrayRef<Expr *> exprs() { return llvm::ArrayRef(getExprs(), getNumExprs()); }
5669
5670	SourceLocation getLParenLoc() const { return LParenLoc; }
5671	SourceLocation getRParenLoc() const { return RParenLoc; }
5672	SourceLocation getBeginLoc() const { return getLParenLoc(); }
5673	SourceLocation getEndLoc() const { return getRParenLoc(); }
5674
5675	static bool classof(const Stmt *T) {
5676	return T->getStmtClass() == ParenListExprClass;
5677	}
5678
5679	// Iterators
5680	child_range children() {
5681	return child_range(getTrailingObjects<Stmt *>(),
5682	getTrailingObjects<Stmt *>() + getNumExprs());
5683	}
5684	const_child_range children() const {
5685	return const_child_range(getTrailingObjects<Stmt *>(),
5686	getTrailingObjects<Stmt *>() + getNumExprs());
5687	}
5688	};
5689
5690	/// Represents a C11 generic selection.
5691	///
5692	/// A generic selection (C11 6.5.1.1) contains an unevaluated controlling
5693	/// expression, followed by one or more generic associations. Each generic
5694	/// association specifies a type name and an expression, or "default" and an
5695	/// expression (in which case it is known as a default generic association).
5696	/// The type and value of the generic selection are identical to those of its
5697	/// result expression, which is defined as the expression in the generic
5698	/// association with a type name that is compatible with the type of the
5699	/// controlling expression, or the expression in the default generic association
5700	/// if no types are compatible. For example:
5701	///
5702	/// @code
5703	/// _Generic(X, double: 1, float: 2, default: 3)
5704	/// @endcode
5705	///
5706	/// The above expression evaluates to 1 if 1.0 is substituted for X, 2 if 1.0f
5707	/// or 3 if "hello".
5708	///
5709	/// As an extension, generic selections are allowed in C++, where the following
5710	/// additional semantics apply:
5711	///
5712	/// Any generic selection whose controlling expression is type-dependent or
5713	/// which names a dependent type in its association list is result-dependent,
5714	/// which means that the choice of result expression is dependent.
5715	/// Result-dependent generic associations are both type- and value-dependent.
5716	///
5717	/// We also allow an extended form in both C and C++ where the controlling
5718	/// predicate for the selection expression is a type rather than an expression.
5719	/// This type argument form does not perform any conversions for the
5720	/// controlling type, which makes it suitable for use with qualified type
5721	/// associations, which is not possible with the expression form.
5722	class GenericSelectionExpr final
5723	: public Expr,
5724	private llvm::TrailingObjects<GenericSelectionExpr, Stmt *,
5725	TypeSourceInfo *> {
5726	friend class ASTStmtReader;
5727	friend class ASTStmtWriter;
5728	friend TrailingObjects;
5729
5730	/// The number of association expressions and the index of the result
5731	/// expression in the case where the generic selection expression is not
5732	/// result-dependent. The result index is equal to ResultDependentIndex
5733	/// if and only if the generic selection expression is result-dependent.
5734	unsigned NumAssocs : 15;
5735	unsigned ResultIndex : 15; // NB: ResultDependentIndex is tied to this width.
5736	LLVM_PREFERRED_TYPE(bool)
5737	unsigned IsExprPredicate : 1;
5738	enum : unsigned {
5739	ResultDependentIndex = 0x7FFF
5740	};
5741
5742	unsigned getIndexOfControllingExpression() const {
5743	// If controlled by an expression, the first offset into the Stmt *
5744	// trailing array is the controlling expression, the associated expressions
5745	// follow this.
5746	assert(isExprPredicate() && "Asking for the controlling expression of a "
5747	"selection expr predicated by a type");
5748	return 0;
5749	}
5750
5751	unsigned getIndexOfControllingType() const {
5752	// If controlled by a type, the first offset into the TypeSourceInfo *
5753	// trailing array is the controlling type, the associated types follow this.
5754	assert(isTypePredicate() && "Asking for the controlling type of a "
5755	"selection expr predicated by an expression");
5756	return 0;
5757	}
5758
5759	unsigned getIndexOfStartOfAssociatedExprs() const {
5760	// If the predicate is a type, then the associated expressions are the only
5761	// Stmt * in the trailing array, otherwise we need to offset past the
5762	// predicate expression.
5763	return (int)isExprPredicate();
5764	}
5765
5766	unsigned getIndexOfStartOfAssociatedTypes() const {
5767	// If the predicate is a type, then the associated types follow it in the
5768	// trailing array. Otherwise, the associated types are the only
5769	// TypeSourceInfo * in the trailing array.
5770	return (int)isTypePredicate();
5771	}
5772
5773
5774	/// The location of the "default" and of the right parenthesis.
5775	SourceLocation DefaultLoc, RParenLoc;
5776
5777	// GenericSelectionExpr is followed by several trailing objects.
5778	// They are (in order):
5779	//
5780	// * A single Stmt * for the controlling expression or a TypeSourceInfo * for
5781	// the controlling type, depending on the result of isTypePredicate() or
5782	// isExprPredicate().
5783	// * An array of getNumAssocs() Stmt * for the association expressions.
5784	// * An array of getNumAssocs() TypeSourceInfo *, one for each of the
5785	// association expressions.
5786	unsigned numTrailingObjects(OverloadToken<Stmt *>) const {
5787	// Add one to account for the controlling expression; the remainder
5788	// are the associated expressions.
5789	return getNumAssocs() + (int)isExprPredicate();
5790	}
5791
5792	unsigned numTrailingObjects(OverloadToken<TypeSourceInfo *>) const {
5793	// Add one to account for the controlling type predicate, the remainder
5794	// are the associated types.
5795	return getNumAssocs() + (int)isTypePredicate();
5796	}
5797
5798	template <bool Const> class AssociationIteratorTy;
5799	/// Bundle together an association expression and its TypeSourceInfo.
5800	/// The Const template parameter is for the const and non-const versions
5801	/// of AssociationTy.
5802	template <bool Const> class AssociationTy {
5803	friend class GenericSelectionExpr;
5804	template <bool OtherConst> friend class AssociationIteratorTy;
5805	using ExprPtrTy = std::conditional_t<Const, const Expr *, Expr *>;
5806	using TSIPtrTy =
5807	std::conditional_t<Const, const TypeSourceInfo *, TypeSourceInfo *>;
5808	ExprPtrTy E;
5809	TSIPtrTy TSI;
5810	bool Selected;
5811	AssociationTy(ExprPtrTy E, TSIPtrTy TSI, bool Selected)
5812	: E(E), TSI(TSI), Selected(Selected) {}
5813
5814	public:
5815	ExprPtrTy getAssociationExpr() const { return E; }
5816	TSIPtrTy getTypeSourceInfo() const { return TSI; }
5817	QualType getType() const { return TSI ? TSI->getType() : QualType(); }
5818	bool isSelected() const { return Selected; }
5819	AssociationTy *operator->() { return this; }
5820	const AssociationTy *operator->() const { return this; }
5821	}; // class AssociationTy
5822
5823	/// Iterator over const and non-const Association objects. The Association
5824	/// objects are created on the fly when the iterator is dereferenced.
5825	/// This abstract over how exactly the association expressions and the
5826	/// corresponding TypeSourceInfo * are stored.
5827	template <bool Const>
5828	class AssociationIteratorTy
5829	: public llvm::iterator_facade_base<
5830	AssociationIteratorTy<Const>, std::input_iterator_tag,
5831	AssociationTy<Const>, std::ptrdiff_t, AssociationTy<Const>,
5832	AssociationTy<Const>> {
5833	friend class GenericSelectionExpr;
5834	// FIXME: This iterator could conceptually be a random access iterator, and
5835	// it would be nice if we could strengthen the iterator category someday.
5836	// However this iterator does not satisfy two requirements of forward
5837	// iterators:
5838	// a) reference = T& or reference = const T&
5839	// b) If It1 and It2 are both dereferenceable, then It1 == It2 if and only
5840	// if *It1 and *It2 are bound to the same objects.
5841	// An alternative design approach was discussed during review;
5842	// store an Association object inside the iterator, and return a reference
5843	// to it when dereferenced. This idea was discarded beacuse of nasty
5844	// lifetime issues:
5845	// AssociationIterator It = ...;
5846	// const Association &Assoc = *It++; // Oops, Assoc is dangling.
5847	using BaseTy = typename AssociationIteratorTy::iterator_facade_base;
5848	using StmtPtrPtrTy =
5849	std::conditional_t<Const, const Stmt *const *, Stmt **>;
5850	using TSIPtrPtrTy = std::conditional_t<Const, const TypeSourceInfo *const *,
5851	TypeSourceInfo **>;
5852	StmtPtrPtrTy E = nullptr;
5853	TSIPtrPtrTy TSI; // Kept in sync with E.
5854	unsigned Offset = 0, SelectedOffset = 0;
5855	AssociationIteratorTy(StmtPtrPtrTy E, TSIPtrPtrTy TSI, unsigned Offset,
5856	unsigned SelectedOffset)
5857	: E(E), TSI(TSI), Offset(Offset), SelectedOffset(SelectedOffset) {}
5858
5859	public:
5860	AssociationIteratorTy() : E(nullptr), TSI(nullptr) {}
5861	typename BaseTy::reference operator*() const {
5862	return AssociationTy<Const>(cast<Expr>(*E), *TSI,
5863	Offset == SelectedOffset);
5864	}
5865	typename BaseTy::pointer operator->() const { return **this; }
5866	using BaseTy::operator++;
5867	AssociationIteratorTy &operator++() {
5868	++E;
5869	++TSI;
5870	++Offset;
5871	return *this;
5872	}
5873	bool operator==(AssociationIteratorTy Other) const { return E == Other.E; }
5874	}; // class AssociationIterator
5875
5876	/// Build a non-result-dependent generic selection expression accepting an
5877	/// expression predicate.
5878	GenericSelectionExpr(const ASTContext &Context, SourceLocation GenericLoc,
5879	Expr *ControllingExpr,
5880	ArrayRef<TypeSourceInfo *> AssocTypes,
5881	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5882	SourceLocation RParenLoc,
5883	bool ContainsUnexpandedParameterPack,
5884	unsigned ResultIndex);
5885
5886	/// Build a result-dependent generic selection expression accepting an
5887	/// expression predicate.
5888	GenericSelectionExpr(const ASTContext &Context, SourceLocation GenericLoc,
5889	Expr *ControllingExpr,
5890	ArrayRef<TypeSourceInfo *> AssocTypes,
5891	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5892	SourceLocation RParenLoc,
5893	bool ContainsUnexpandedParameterPack);
5894
5895	/// Build a non-result-dependent generic selection expression accepting a
5896	/// type predicate.
5897	GenericSelectionExpr(const ASTContext &Context, SourceLocation GenericLoc,
5898	TypeSourceInfo *ControllingType,
5899	ArrayRef<TypeSourceInfo *> AssocTypes,
5900	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5901	SourceLocation RParenLoc,
5902	bool ContainsUnexpandedParameterPack,
5903	unsigned ResultIndex);
5904
5905	/// Build a result-dependent generic selection expression accepting a type
5906	/// predicate.
5907	GenericSelectionExpr(const ASTContext &Context, SourceLocation GenericLoc,
5908	TypeSourceInfo *ControllingType,
5909	ArrayRef<TypeSourceInfo *> AssocTypes,
5910	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5911	SourceLocation RParenLoc,
5912	bool ContainsUnexpandedParameterPack);
5913
5914	/// Build an empty generic selection expression for deserialization.
5915	explicit GenericSelectionExpr(EmptyShell Empty, unsigned NumAssocs);
5916
5917	public:
5918	/// Create a non-result-dependent generic selection expression accepting an
5919	/// expression predicate.
5920	static GenericSelectionExpr *
5921	Create(const ASTContext &Context, SourceLocation GenericLoc,
5922	Expr *ControllingExpr, ArrayRef<TypeSourceInfo *> AssocTypes,
5923	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5924	SourceLocation RParenLoc, bool ContainsUnexpandedParameterPack,
5925	unsigned ResultIndex);
5926
5927	/// Create a result-dependent generic selection expression accepting an
5928	/// expression predicate.
5929	static GenericSelectionExpr *
5930	Create(const ASTContext &Context, SourceLocation GenericLoc,
5931	Expr *ControllingExpr, ArrayRef<TypeSourceInfo *> AssocTypes,
5932	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5933	SourceLocation RParenLoc, bool ContainsUnexpandedParameterPack);
5934
5935	/// Create a non-result-dependent generic selection expression accepting a
5936	/// type predicate.
5937	static GenericSelectionExpr *
5938	Create(const ASTContext &Context, SourceLocation GenericLoc,
5939	TypeSourceInfo *ControllingType, ArrayRef<TypeSourceInfo *> AssocTypes,
5940	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5941	SourceLocation RParenLoc, bool ContainsUnexpandedParameterPack,
5942	unsigned ResultIndex);
5943
5944	/// Create a result-dependent generic selection expression accepting a type
5945	/// predicate
5946	static GenericSelectionExpr *
5947	Create(const ASTContext &Context, SourceLocation GenericLoc,
5948	TypeSourceInfo *ControllingType, ArrayRef<TypeSourceInfo *> AssocTypes,
5949	ArrayRef<Expr *> AssocExprs, SourceLocation DefaultLoc,
5950	SourceLocation RParenLoc, bool ContainsUnexpandedParameterPack);
5951
5952	/// Create an empty generic selection expression for deserialization.
5953	static GenericSelectionExpr *CreateEmpty(const ASTContext &Context,
5954	unsigned NumAssocs);
5955
5956	using Association = AssociationTy<false>;
5957	using ConstAssociation = AssociationTy<true>;
5958	using AssociationIterator = AssociationIteratorTy<false>;
5959	using ConstAssociationIterator = AssociationIteratorTy<true>;
5960	using association_range = llvm::iterator_range<AssociationIterator>;
5961	using const_association_range =
5962	llvm::iterator_range<ConstAssociationIterator>;
5963
5964	/// The number of association expressions.
5965	unsigned getNumAssocs() const { return NumAssocs; }
5966
5967	/// The zero-based index of the result expression's generic association in
5968	/// the generic selection's association list. Defined only if the
5969	/// generic selection is not result-dependent.
5970	unsigned getResultIndex() const {
5971	assert(!isResultDependent() &&
5972	"Generic selection is result-dependent but getResultIndex called!");
5973	return ResultIndex;
5974	}
5975
5976	/// Whether this generic selection is result-dependent.
5977	bool isResultDependent() const { return ResultIndex == ResultDependentIndex; }
5978
5979	/// Whether this generic selection uses an expression as its controlling
5980	/// argument.
5981	bool isExprPredicate() const { return IsExprPredicate; }
5982	/// Whether this generic selection uses a type as its controlling argument.
5983	bool isTypePredicate() const { return !IsExprPredicate; }
5984
5985	/// Return the controlling expression of this generic selection expression.
5986	/// Only valid to call if the selection expression used an expression as its
5987	/// controlling argument.
5988	Expr *getControllingExpr() {
5989	return cast<Expr>(
5990	getTrailingObjects<Stmt *>()[getIndexOfControllingExpression()]);
5991	}
5992	const Expr *getControllingExpr() const {
5993	return cast<Expr>(
5994	getTrailingObjects<Stmt *>()[getIndexOfControllingExpression()]);
5995	}
5996
5997	/// Return the controlling type of this generic selection expression. Only
5998	/// valid to call if the selection expression used a type as its controlling
5999	/// argument.
6000	TypeSourceInfo *getControllingType() {
6001	return getTrailingObjects<TypeSourceInfo *>()[getIndexOfControllingType()];
6002	}
6003	const TypeSourceInfo* getControllingType() const {
6004	return getTrailingObjects<TypeSourceInfo *>()[getIndexOfControllingType()];
6005	}
6006
6007	/// Return the result expression of this controlling expression. Defined if
6008	/// and only if the generic selection expression is not result-dependent.
6009	Expr *getResultExpr() {
6010	return cast<Expr>(
6011	getTrailingObjects<Stmt *>()[getIndexOfStartOfAssociatedExprs() +
6012	getResultIndex()]);
6013	}
6014	const Expr *getResultExpr() const {
6015	return cast<Expr>(
6016	getTrailingObjects<Stmt *>()[getIndexOfStartOfAssociatedExprs() +
6017	getResultIndex()]);
6018	}
6019
6020	ArrayRef<Expr *> getAssocExprs() const {
6021	return {reinterpret_cast<Expr *const *>(getTrailingObjects<Stmt *>() +
6022	getIndexOfStartOfAssociatedExprs()),
6023	NumAssocs};
6024	}
6025	ArrayRef<TypeSourceInfo *> getAssocTypeSourceInfos() const {
6026	return {getTrailingObjects<TypeSourceInfo *>() +
6027	getIndexOfStartOfAssociatedTypes(),
6028	NumAssocs};
6029	}
6030
6031	/// Return the Ith association expression with its TypeSourceInfo,
6032	/// bundled together in GenericSelectionExpr::(Const)Association.
6033	Association getAssociation(unsigned I) {
6034	assert(I < getNumAssocs() &&
6035	"Out-of-range index in GenericSelectionExpr::getAssociation!");
6036	return Association(
6037	cast<Expr>(
6038	getTrailingObjects<Stmt *>()[getIndexOfStartOfAssociatedExprs() +
6039	I]),
6040	getTrailingObjects<
6041	TypeSourceInfo *>()[getIndexOfStartOfAssociatedTypes() + I],
6042	!isResultDependent() && (getResultIndex() == I));
6043	}
6044	ConstAssociation getAssociation(unsigned I) const {
6045	assert(I < getNumAssocs() &&
6046	"Out-of-range index in GenericSelectionExpr::getAssociation!");
6047	return ConstAssociation(
6048	cast<Expr>(
6049	getTrailingObjects<Stmt *>()[getIndexOfStartOfAssociatedExprs() +
6050	I]),
6051	getTrailingObjects<
6052	TypeSourceInfo *>()[getIndexOfStartOfAssociatedTypes() + I],
6053	!isResultDependent() && (getResultIndex() == I));
6054	}
6055
6056	association_range associations() {
6057	AssociationIterator Begin(getTrailingObjects<Stmt *>() +
6058	getIndexOfStartOfAssociatedExprs(),
6059	getTrailingObjects<TypeSourceInfo *>() +
6060	getIndexOfStartOfAssociatedTypes(),
6061	/*Offset=*/0, ResultIndex);
6062	AssociationIterator End(Begin.E + NumAssocs, Begin.TSI + NumAssocs,
6063	/*Offset=*/NumAssocs, ResultIndex);
6064	return llvm::make_range(x: Begin, y: End);
6065	}
6066
6067	const_association_range associations() const {
6068	ConstAssociationIterator Begin(getTrailingObjects<Stmt *>() +
6069	getIndexOfStartOfAssociatedExprs(),
6070	getTrailingObjects<TypeSourceInfo *>() +
6071	getIndexOfStartOfAssociatedTypes(),
6072	/*Offset=*/0, ResultIndex);
6073	ConstAssociationIterator End(Begin.E + NumAssocs, Begin.TSI + NumAssocs,
6074	/*Offset=*/NumAssocs, ResultIndex);
6075	return llvm::make_range(x: Begin, y: End);
6076	}
6077
6078	SourceLocation getGenericLoc() const {
6079	return GenericSelectionExprBits.GenericLoc;
6080	}
6081	SourceLocation getDefaultLoc() const { return DefaultLoc; }
6082	SourceLocation getRParenLoc() const { return RParenLoc; }
6083	SourceLocation getBeginLoc() const { return getGenericLoc(); }
6084	SourceLocation getEndLoc() const { return getRParenLoc(); }
6085
6086	static bool classof(const Stmt *T) {
6087	return T->getStmtClass() == GenericSelectionExprClass;
6088	}
6089
6090	child_range children() {
6091	return child_range(getTrailingObjects<Stmt *>(),
6092	getTrailingObjects<Stmt *>() +
6093	numTrailingObjects(OverloadToken<Stmt *>()));
6094	}
6095	const_child_range children() const {
6096	return const_child_range(getTrailingObjects<Stmt *>(),
6097	getTrailingObjects<Stmt *>() +
6098	numTrailingObjects(OverloadToken<Stmt *>()));
6099	}
6100	};
6101
6102	//===----------------------------------------------------------------------===//
6103	// Clang Extensions
6104	//===----------------------------------------------------------------------===//
6105
6106	/// ExtVectorElementExpr - This represents access to specific elements of a
6107	/// vector, and may occur on the left hand side or right hand side. For example
6108	/// the following is legal: "V.xy = V.zw" if V is a 4 element extended vector.
6109	///
6110	/// Note that the base may have either vector or pointer to vector type, just
6111	/// like a struct field reference.
6112	///
6113	class ExtVectorElementExpr : public Expr {
6114	Stmt *Base;
6115	IdentifierInfo *Accessor;
6116	SourceLocation AccessorLoc;
6117	public:
6118	ExtVectorElementExpr(QualType ty, ExprValueKind VK, Expr *base,
6119	IdentifierInfo &accessor, SourceLocation loc)
6120	: Expr(ExtVectorElementExprClass, ty, VK,
6121	(VK == VK_PRValue ? OK_Ordinary : OK_VectorComponent)),
6122	Base(base), Accessor(&accessor), AccessorLoc(loc) {
6123	setDependence(computeDependence(E: this));
6124	}
6125
6126	/// Build an empty vector element expression.
6127	explicit ExtVectorElementExpr(EmptyShell Empty)
6128	: Expr(ExtVectorElementExprClass, Empty) { }
6129
6130	const Expr *getBase() const { return cast<Expr>(Val: Base); }
6131	Expr *getBase() { return cast<Expr>(Val: Base); }
6132	void setBase(Expr *E) { Base = E; }
6133
6134	IdentifierInfo &getAccessor() const { return *Accessor; }
6135	void setAccessor(IdentifierInfo *II) { Accessor = II; }
6136
6137	SourceLocation getAccessorLoc() const { return AccessorLoc; }
6138	void setAccessorLoc(SourceLocation L) { AccessorLoc = L; }
6139
6140	/// getNumElements - Get the number of components being selected.
6141	unsigned getNumElements() const;
6142
6143	/// containsDuplicateElements - Return true if any element access is
6144	/// repeated.
6145	bool containsDuplicateElements() const;
6146
6147	/// getEncodedElementAccess - Encode the elements accessed into an llvm
6148	/// aggregate Constant of ConstantInt(s).
6149	void getEncodedElementAccess(SmallVectorImpl<uint32_t> &Elts) const;
6150
6151	SourceLocation getBeginLoc() const LLVM_READONLY {
6152	return getBase()->getBeginLoc();
6153	}
6154	SourceLocation getEndLoc() const LLVM_READONLY { return AccessorLoc; }
6155
6156	/// isArrow - Return true if the base expression is a pointer to vector,
6157	/// return false if the base expression is a vector.
6158	bool isArrow() const;
6159
6160	static bool classof(const Stmt *T) {
6161	return T->getStmtClass() == ExtVectorElementExprClass;
6162	}
6163
6164	// Iterators
6165	child_range children() { return child_range(&Base, &Base+1); }
6166	const_child_range children() const {
6167	return const_child_range(&Base, &Base + 1);
6168	}
6169	};
6170
6171	/// BlockExpr - Adaptor class for mixing a BlockDecl with expressions.
6172	/// ^{ statement-body } or ^(int arg1, float arg2){ statement-body }
6173	class BlockExpr : public Expr {
6174	protected:
6175	BlockDecl *TheBlock;
6176	public:
6177	BlockExpr(BlockDecl *BD, QualType ty)
6178	: Expr(BlockExprClass, ty, VK_PRValue, OK_Ordinary), TheBlock(BD) {
6179	setDependence(computeDependence(E: this));
6180	}
6181
6182	/// Build an empty block expression.
6183	explicit BlockExpr(EmptyShell Empty) : Expr(BlockExprClass, Empty) { }
6184
6185	const BlockDecl *getBlockDecl() const { return TheBlock; }
6186	BlockDecl *getBlockDecl() { return TheBlock; }
6187	void setBlockDecl(BlockDecl *BD) { TheBlock = BD; }
6188
6189	// Convenience functions for probing the underlying BlockDecl.
6190	SourceLocation getCaretLocation() const;
6191	const Stmt *getBody() const;
6192	Stmt *getBody();
6193
6194	SourceLocation getBeginLoc() const LLVM_READONLY {
6195	return getCaretLocation();
6196	}
6197	SourceLocation getEndLoc() const LLVM_READONLY {
6198	return getBody()->getEndLoc();
6199	}
6200
6201	/// getFunctionType - Return the underlying function type for this block.
6202	const FunctionProtoType *getFunctionType() const;
6203
6204	static bool classof(const Stmt *T) {
6205	return T->getStmtClass() == BlockExprClass;
6206	}
6207
6208	// Iterators
6209	child_range children() {
6210	return child_range(child_iterator(), child_iterator());
6211	}
6212	const_child_range children() const {
6213	return const_child_range(const_child_iterator(), const_child_iterator());
6214	}
6215	};
6216
6217	/// Copy initialization expr of a __block variable and a boolean flag that
6218	/// indicates whether the expression can throw.
6219	struct BlockVarCopyInit {
6220	BlockVarCopyInit() = default;
6221	BlockVarCopyInit(Expr *CopyExpr, bool CanThrow)
6222	: ExprAndFlag(CopyExpr, CanThrow) {}
6223	void setExprAndFlag(Expr *CopyExpr, bool CanThrow) {
6224	ExprAndFlag.setPointerAndInt(PtrVal: CopyExpr, IntVal: CanThrow);
6225	}
6226	Expr *getCopyExpr() const { return ExprAndFlag.getPointer(); }
6227	bool canThrow() const { return ExprAndFlag.getInt(); }
6228	llvm::PointerIntPair<Expr *, 1, bool> ExprAndFlag;
6229	};
6230
6231	/// AsTypeExpr - Clang builtin function __builtin_astype [OpenCL 6.2.4.2]
6232	/// This AST node provides support for reinterpreting a type to another
6233	/// type of the same size.
6234	class AsTypeExpr : public Expr {
6235	private:
6236	Stmt *SrcExpr;
6237	SourceLocation BuiltinLoc, RParenLoc;
6238
6239	friend class ASTReader;
6240	friend class ASTStmtReader;
6241	explicit AsTypeExpr(EmptyShell Empty) : Expr(AsTypeExprClass, Empty) {}
6242
6243	public:
6244	AsTypeExpr(Expr *SrcExpr, QualType DstType, ExprValueKind VK,
6245	ExprObjectKind OK, SourceLocation BuiltinLoc,
6246	SourceLocation RParenLoc)
6247	: Expr(AsTypeExprClass, DstType, VK, OK), SrcExpr(SrcExpr),
6248	BuiltinLoc(BuiltinLoc), RParenLoc(RParenLoc) {
6249	setDependence(computeDependence(E: this));
6250	}
6251
6252	/// getSrcExpr - Return the Expr to be converted.
6253	Expr *getSrcExpr() const { return cast<Expr>(Val: SrcExpr); }
6254
6255	/// getBuiltinLoc - Return the location of the __builtin_astype token.
6256	SourceLocation getBuiltinLoc() const { return BuiltinLoc; }
6257
6258	/// getRParenLoc - Return the location of final right parenthesis.
6259	SourceLocation getRParenLoc() const { return RParenLoc; }
6260
6261	SourceLocation getBeginLoc() const LLVM_READONLY { return BuiltinLoc; }
6262	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
6263
6264	static bool classof(const Stmt *T) {
6265	return T->getStmtClass() == AsTypeExprClass;
6266	}
6267
6268	// Iterators
6269	child_range children() { return child_range(&SrcExpr, &SrcExpr+1); }
6270	const_child_range children() const {
6271	return const_child_range(&SrcExpr, &SrcExpr + 1);
6272	}
6273	};
6274
6275	/// PseudoObjectExpr - An expression which accesses a pseudo-object
6276	/// l-value. A pseudo-object is an abstract object, accesses to which
6277	/// are translated to calls. The pseudo-object expression has a
6278	/// syntactic form, which shows how the expression was actually
6279	/// written in the source code, and a semantic form, which is a series
6280	/// of expressions to be executed in order which detail how the
6281	/// operation is actually evaluated. Optionally, one of the semantic
6282	/// forms may also provide a result value for the expression.
6283	///
6284	/// If any of the semantic-form expressions is an OpaqueValueExpr,
6285	/// that OVE is required to have a source expression, and it is bound
6286	/// to the result of that source expression. Such OVEs may appear
6287	/// only in subsequent semantic-form expressions and as
6288	/// sub-expressions of the syntactic form.
6289	///
6290	/// PseudoObjectExpr should be used only when an operation can be
6291	/// usefully described in terms of fairly simple rewrite rules on
6292	/// objects and functions that are meant to be used by end-developers.
6293	/// For example, under the Itanium ABI, dynamic casts are implemented
6294	/// as a call to a runtime function called __dynamic_cast; using this
6295	/// class to describe that would be inappropriate because that call is
6296	/// not really part of the user-visible semantics, and instead the
6297	/// cast is properly reflected in the AST and IR-generation has been
6298	/// taught to generate the call as necessary. In contrast, an
6299	/// Objective-C property access is semantically defined to be
6300	/// equivalent to a particular message send, and this is very much
6301	/// part of the user model. The name of this class encourages this
6302	/// modelling design.
6303	class PseudoObjectExpr final
6304	: public Expr,
6305	private llvm::TrailingObjects<PseudoObjectExpr, Expr *> {
6306	// PseudoObjectExprBits.NumSubExprs - The number of sub-expressions.
6307	// Always at least two, because the first sub-expression is the
6308	// syntactic form.
6309
6310	// PseudoObjectExprBits.ResultIndex - The index of the
6311	// sub-expression holding the result. 0 means the result is void,
6312	// which is unambiguous because it's the index of the syntactic
6313	// form. Note that this is therefore 1 higher than the value passed
6314	// in to Create, which is an index within the semantic forms.
6315	// Note also that ASTStmtWriter assumes this encoding.
6316
6317	Expr **getSubExprsBuffer() { return getTrailingObjects<Expr *>(); }
6318	const Expr * const *getSubExprsBuffer() const {
6319	return getTrailingObjects<Expr *>();
6320	}
6321
6322	PseudoObjectExpr(QualType type, ExprValueKind VK,
6323	Expr *syntactic, ArrayRef<Expr*> semantic,
6324	unsigned resultIndex);
6325
6326	PseudoObjectExpr(EmptyShell shell, unsigned numSemanticExprs);
6327
6328	unsigned getNumSubExprs() const {
6329	return PseudoObjectExprBits.NumSubExprs;
6330	}
6331
6332	public:
6333	/// NoResult - A value for the result index indicating that there is
6334	/// no semantic result.
6335	enum : unsigned { NoResult = ~0U };
6336
6337	static PseudoObjectExpr *Create(const ASTContext &Context, Expr *syntactic,
6338	ArrayRef<Expr*> semantic,
6339	unsigned resultIndex);
6340
6341	static PseudoObjectExpr *Create(const ASTContext &Context, EmptyShell shell,
6342	unsigned numSemanticExprs);
6343
6344	/// Return the syntactic form of this expression, i.e. the
6345	/// expression it actually looks like. Likely to be expressed in
6346	/// terms of OpaqueValueExprs bound in the semantic form.
6347	Expr *getSyntacticForm() { return getSubExprsBuffer()[0]; }
6348	const Expr *getSyntacticForm() const { return getSubExprsBuffer()[0]; }
6349
6350	/// Return the index of the result-bearing expression into the semantics
6351	/// expressions, or PseudoObjectExpr::NoResult if there is none.
6352	unsigned getResultExprIndex() const {
6353	if (PseudoObjectExprBits.ResultIndex == 0) return NoResult;
6354	return PseudoObjectExprBits.ResultIndex - 1;
6355	}
6356
6357	/// Return the result-bearing expression, or null if there is none.
6358	Expr *getResultExpr() {
6359	if (PseudoObjectExprBits.ResultIndex == 0)
6360	return nullptr;
6361	return getSubExprsBuffer()[PseudoObjectExprBits.ResultIndex];
6362	}
6363	const Expr *getResultExpr() const {
6364	return const_cast<PseudoObjectExpr*>(this)->getResultExpr();
6365	}
6366
6367	unsigned getNumSemanticExprs() const { return getNumSubExprs() - 1; }
6368
6369	typedef Expr * const *semantics_iterator;
6370	typedef const Expr * const *const_semantics_iterator;
6371	semantics_iterator semantics_begin() {
6372	return getSubExprsBuffer() + 1;
6373	}
6374	const_semantics_iterator semantics_begin() const {
6375	return getSubExprsBuffer() + 1;
6376	}
6377	semantics_iterator semantics_end() {
6378	return getSubExprsBuffer() + getNumSubExprs();
6379	}
6380	const_semantics_iterator semantics_end() const {
6381	return getSubExprsBuffer() + getNumSubExprs();
6382	}
6383
6384	ArrayRef<Expr*> semantics() {
6385	return ArrayRef(semantics_begin(), semantics_end());
6386	}
6387	ArrayRef<const Expr*> semantics() const {
6388	return ArrayRef(semantics_begin(), semantics_end());
6389	}
6390
6391	Expr *getSemanticExpr(unsigned index) {
6392	assert(index + 1 < getNumSubExprs());
6393	return getSubExprsBuffer()[index + 1];
6394	}
6395	const Expr *getSemanticExpr(unsigned index) const {
6396	return const_cast<PseudoObjectExpr*>(this)->getSemanticExpr(index);
6397	}
6398
6399	SourceLocation getExprLoc() const LLVM_READONLY {
6400	return getSyntacticForm()->getExprLoc();
6401	}
6402
6403	SourceLocation getBeginLoc() const LLVM_READONLY {
6404	return getSyntacticForm()->getBeginLoc();
6405	}
6406	SourceLocation getEndLoc() const LLVM_READONLY {
6407	return getSyntacticForm()->getEndLoc();
6408	}
6409
6410	child_range children() {
6411	const_child_range CCR =
6412	const_cast<const PseudoObjectExpr *>(this)->children();
6413	return child_range(cast_away_const(RHS: CCR.begin()),
6414	cast_away_const(RHS: CCR.end()));
6415	}
6416	const_child_range children() const {
6417	Stmt *const *cs = const_cast<Stmt *const *>(
6418	reinterpret_cast<const Stmt *const *>(getSubExprsBuffer()));
6419	return const_child_range(cs, cs + getNumSubExprs());
6420	}
6421
6422	static bool classof(const Stmt *T) {
6423	return T->getStmtClass() == PseudoObjectExprClass;
6424	}
6425
6426	friend TrailingObjects;
6427	friend class ASTStmtReader;
6428	};
6429
6430	/// AtomicExpr - Variadic atomic builtins: __atomic_exchange, __atomic_fetch_*,
6431	/// __atomic_load, __atomic_store, and __atomic_compare_exchange_*, for the
6432	/// similarly-named C++11 instructions, and __c11 variants for <stdatomic.h>,
6433	/// and corresponding __opencl_atomic_* for OpenCL 2.0.
6434	/// All of these instructions take one primary pointer, at least one memory
6435	/// order. The instructions for which getScopeModel returns non-null value
6436	/// take one synch scope.
6437	class AtomicExpr : public Expr {
6438	public:
6439	enum AtomicOp {
6440	#define BUILTIN(ID, TYPE, ATTRS)
6441	#define ATOMIC_BUILTIN(ID, TYPE, ATTRS) AO ## ID,
6442	#include "clang/Basic/Builtins.inc"
6443	// Avoid trailing comma
6444	BI_First = 0
6445	};
6446
6447	private:
6448	/// Location of sub-expressions.
6449	/// The location of Scope sub-expression is NumSubExprs - 1, which is
6450	/// not fixed, therefore is not defined in enum.
6451	enum { PTR, ORDER, VAL1, ORDER_FAIL, VAL2, WEAK, END_EXPR };
6452	Stmt *SubExprs[END_EXPR + 1];
6453	unsigned NumSubExprs;
6454	SourceLocation BuiltinLoc, RParenLoc;
6455	AtomicOp Op;
6456
6457	friend class ASTStmtReader;
6458	public:
6459	AtomicExpr(SourceLocation BLoc, ArrayRef<Expr*> args, QualType t,
6460	AtomicOp op, SourceLocation RP);
6461
6462	/// Determine the number of arguments the specified atomic builtin
6463	/// should have.
6464	static unsigned getNumSubExprs(AtomicOp Op);
6465
6466	/// Build an empty AtomicExpr.
6467	explicit AtomicExpr(EmptyShell Empty) : Expr(AtomicExprClass, Empty) { }
6468
6469	Expr *getPtr() const {
6470	return cast<Expr>(SubExprs[PTR]);
6471	}
6472	Expr *getOrder() const {
6473	return cast<Expr>(SubExprs[ORDER]);
6474	}
6475	Expr *getScope() const {
6476	assert(getScopeModel() && "No scope");
6477	return cast<Expr>(SubExprs[NumSubExprs - 1]);
6478	}
6479	Expr *getVal1() const {
6480	if (Op == AO__c11_atomic_init || Op == AO__opencl_atomic_init)
6481	return cast<Expr>(SubExprs[ORDER]);
6482	assert(NumSubExprs > VAL1);
6483	return cast<Expr>(SubExprs[VAL1]);
6484	}
6485	Expr *getOrderFail() const {
6486	assert(NumSubExprs > ORDER_FAIL);
6487	return cast<Expr>(SubExprs[ORDER_FAIL]);
6488	}
6489	Expr *getVal2() const {
6490	if (Op == AO__atomic_exchange || Op == AO__scoped_atomic_exchange)
6491	return cast<Expr>(SubExprs[ORDER_FAIL]);
6492	assert(NumSubExprs > VAL2);
6493	return cast<Expr>(SubExprs[VAL2]);
6494	}
6495	Expr *getWeak() const {
6496	assert(NumSubExprs > WEAK);
6497	return cast<Expr>(SubExprs[WEAK]);
6498	}
6499	QualType getValueType() const;
6500
6501	AtomicOp getOp() const { return Op; }
6502	StringRef getOpAsString() const {
6503	switch (Op) {
6504	#define BUILTIN(ID, TYPE, ATTRS)
6505	#define ATOMIC_BUILTIN(ID, TYPE, ATTRS) \
6506	case AO##ID: \
6507	return #ID;
6508	#include "clang/Basic/Builtins.inc"
6509	}
6510	llvm_unreachable("not an atomic operator?");
6511	}
6512	unsigned getNumSubExprs() const { return NumSubExprs; }
6513
6514	Expr **getSubExprs() { return reinterpret_cast<Expr **>(SubExprs); }
6515	const Expr * const *getSubExprs() const {
6516	return reinterpret_cast<Expr * const *>(SubExprs);
6517	}
6518
6519	bool isVolatile() const {
6520	return getPtr()->getType()->getPointeeType().isVolatileQualified();
6521	}
6522
6523	bool isCmpXChg() const {
6524	return getOp() == AO__c11_atomic_compare_exchange_strong ||
6525	getOp() == AO__c11_atomic_compare_exchange_weak ||
6526	getOp() == AO__hip_atomic_compare_exchange_strong ||
6527	getOp() == AO__opencl_atomic_compare_exchange_strong ||
6528	getOp() == AO__opencl_atomic_compare_exchange_weak ||
6529	getOp() == AO__hip_atomic_compare_exchange_weak ||
6530	getOp() == AO__atomic_compare_exchange ||
6531	getOp() == AO__atomic_compare_exchange_n ||
6532	getOp() == AO__scoped_atomic_compare_exchange ||
6533	getOp() == AO__scoped_atomic_compare_exchange_n;
6534	}
6535
6536	bool isOpenCL() const {
6537	return getOp() >= AO__opencl_atomic_compare_exchange_strong &&
6538	getOp() <= AO__opencl_atomic_store;
6539	}
6540
6541	SourceLocation getBuiltinLoc() const { return BuiltinLoc; }
6542	SourceLocation getRParenLoc() const { return RParenLoc; }
6543
6544	SourceLocation getBeginLoc() const LLVM_READONLY { return BuiltinLoc; }
6545	SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
6546
6547	static bool classof(const Stmt *T) {
6548	return T->getStmtClass() == AtomicExprClass;
6549	}
6550
6551	// Iterators
6552	child_range children() {
6553	return child_range(SubExprs, SubExprs+NumSubExprs);
6554	}
6555	const_child_range children() const {
6556	return const_child_range(SubExprs, SubExprs + NumSubExprs);
6557	}
6558
6559	/// Get atomic scope model for the atomic op code.
6560	/// \return empty atomic scope model if the atomic op code does not have
6561	/// scope operand.
6562	static std::unique_ptr<AtomicScopeModel> getScopeModel(AtomicOp Op) {
6563	// FIXME: Allow grouping of builtins to be able to only check >= and <=
6564	if (Op >= AO__opencl_atomic_compare_exchange_strong &&
6565	Op <= AO__opencl_atomic_store && Op != AO__opencl_atomic_init)
6566	return AtomicScopeModel::create(K: AtomicScopeModelKind::OpenCL);
6567	if (Op >= AO__hip_atomic_compare_exchange_strong &&
6568	Op <= AO__hip_atomic_store)
6569	return AtomicScopeModel::create(K: AtomicScopeModelKind::HIP);
6570	if (Op >= AO__scoped_atomic_add_fetch && Op <= AO__scoped_atomic_xor_fetch)
6571	return AtomicScopeModel::create(K: AtomicScopeModelKind::Generic);
6572	return AtomicScopeModel::create(K: AtomicScopeModelKind::None);
6573	}
6574
6575	/// Get atomic scope model.
6576	/// \return empty atomic scope model if this atomic expression does not have
6577	/// scope operand.
6578	std::unique_ptr<AtomicScopeModel> getScopeModel() const {
6579	return getScopeModel(getOp());
6580	}
6581	};
6582
6583	/// TypoExpr - Internal placeholder for expressions where typo correction
6584	/// still needs to be performed and/or an error diagnostic emitted.
6585	class TypoExpr : public Expr {
6586	// The location for the typo name.
6587	SourceLocation TypoLoc;
6588
6589	public:
6590	TypoExpr(QualType T, SourceLocation TypoLoc)
6591	: Expr(TypoExprClass, T, VK_LValue, OK_Ordinary), TypoLoc(TypoLoc) {
6592	assert(T->isDependentType() && "TypoExpr given a non-dependent type");
6593	setDependence(ExprDependence::TypeValueInstantiation |
6594	ExprDependence::Error);
6595	}
6596
6597	child_range children() {
6598	return child_range(child_iterator(), child_iterator());
6599	}
6600	const_child_range children() const {
6601	return const_child_range(const_child_iterator(), const_child_iterator());
6602	}
6603
6604	SourceLocation getBeginLoc() const LLVM_READONLY { return TypoLoc; }
6605	SourceLocation getEndLoc() const LLVM_READONLY { return TypoLoc; }
6606
6607	static bool classof(const Stmt *T) {
6608	return T->getStmtClass() == TypoExprClass;
6609	}
6610
6611	};
6612
6613	/// Frontend produces RecoveryExprs on semantic errors that prevent creating
6614	/// other well-formed expressions. E.g. when type-checking of a binary operator
6615	/// fails, we cannot produce a BinaryOperator expression. Instead, we can choose
6616	/// to produce a recovery expression storing left and right operands.
6617	///
6618	/// RecoveryExpr does not have any semantic meaning in C++, it is only useful to
6619	/// preserve expressions in AST that would otherwise be dropped. It captures
6620	/// subexpressions of some expression that we could not construct and source
6621	/// range covered by the expression.
6622	///
6623	/// By default, RecoveryExpr uses dependence-bits to take advantage of existing
6624	/// machinery to deal with dependent code in C++, e.g. RecoveryExpr is preserved
6625	/// in `decltype(<broken-expr>)` as part of the `DependentDecltypeType`. In
6626	/// addition to that, clang does not report most errors on dependent
6627	/// expressions, so we get rid of bogus errors for free. However, note that
6628	/// unlike other dependent expressions, RecoveryExpr can be produced in
6629	/// non-template contexts.
6630	///
6631	/// We will preserve the type in RecoveryExpr when the type is known, e.g.
6632	/// preserving the return type for a broken non-overloaded function call, a
6633	/// overloaded call where all candidates have the same return type. In this
6634	/// case, the expression is not type-dependent (unless the known type is itself
6635	/// dependent)
6636	///
6637	/// One can also reliably suppress all bogus errors on expressions containing
6638	/// recovery expressions by examining results of Expr::containsErrors().
6639	class RecoveryExpr final : public Expr,
6640	private llvm::TrailingObjects<RecoveryExpr, Expr *> {
6641	public:
6642	static RecoveryExpr *Create(ASTContext &Ctx, QualType T,
6643	SourceLocation BeginLoc, SourceLocation EndLoc,
6644	ArrayRef<Expr *> SubExprs);
6645	static RecoveryExpr *CreateEmpty(ASTContext &Ctx, unsigned NumSubExprs);
6646
6647	ArrayRef<Expr *> subExpressions() {
6648	auto *B = getTrailingObjects<Expr *>();
6649	return llvm::ArrayRef(B, B + NumExprs);
6650	}
6651
6652	ArrayRef<const Expr *> subExpressions() const {
6653	return const_cast<RecoveryExpr *>(this)->subExpressions();
6654	}
6655
6656	child_range children() {
6657	Stmt **B = reinterpret_cast<Stmt **>(getTrailingObjects<Expr *>());
6658	return child_range(B, B + NumExprs);
6659	}
6660
6661	SourceLocation getBeginLoc() const { return BeginLoc; }
6662	SourceLocation getEndLoc() const { return EndLoc; }
6663
6664	static bool classof(const Stmt *T) {
6665	return T->getStmtClass() == RecoveryExprClass;
6666	}
6667
6668	private:
6669	RecoveryExpr(ASTContext &Ctx, QualType T, SourceLocation BeginLoc,
6670	SourceLocation EndLoc, ArrayRef<Expr *> SubExprs);
6671	RecoveryExpr(EmptyShell Empty, unsigned NumSubExprs)
6672	: Expr(RecoveryExprClass, Empty), NumExprs(NumSubExprs) {}
6673
6674	size_t numTrailingObjects(OverloadToken<Stmt *>) const { return NumExprs; }
6675
6676	SourceLocation BeginLoc, EndLoc;
6677	unsigned NumExprs;
6678	friend TrailingObjects;
6679	friend class ASTStmtReader;
6680	friend class ASTStmtWriter;
6681	};
6682
6683	} // end namespace clang
6684
6685	#endif // LLVM_CLANG_AST_EXPR_H
6686