1//===- Stmt.h - Classes for representing statements -------------*- 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 Stmt interface and subclasses.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_CLANG_AST_STMT_H
14#define LLVM_CLANG_AST_STMT_H
15
16#include "clang/AST/DeclGroup.h"
17#include "clang/AST/DependenceFlags.h"
18#include "clang/AST/StmtIterator.h"
19#include "clang/Basic/CapturedStmt.h"
20#include "clang/Basic/IdentifierTable.h"
21#include "clang/Basic/LLVM.h"
22#include "clang/Basic/LangOptions.h"
23#include "clang/Basic/SourceLocation.h"
24#include "clang/Basic/Specifiers.h"
25#include "llvm/ADT/APFloat.h"
26#include "llvm/ADT/ArrayRef.h"
27#include "llvm/ADT/BitmaskEnum.h"
28#include "llvm/ADT/PointerIntPair.h"
29#include "llvm/ADT/StringRef.h"
30#include "llvm/ADT/iterator.h"
31#include "llvm/ADT/iterator_range.h"
32#include "llvm/Support/Casting.h"
33#include "llvm/Support/Compiler.h"
34#include "llvm/Support/ErrorHandling.h"
35#include <algorithm>
36#include <cassert>
37#include <cstddef>
38#include <iterator>
39#include <optional>
40#include <string>
41
42namespace llvm {
43
44class FoldingSetNodeID;
45
46} // namespace llvm
47
48namespace clang {
49
50class ASTContext;
51class Attr;
52class CapturedDecl;
53class Decl;
54class Expr;
55class AddrLabelExpr;
56class LabelDecl;
57class ODRHash;
58class PrinterHelper;
59struct PrintingPolicy;
60class RecordDecl;
61class SourceManager;
62class StringLiteral;
63class Token;
64class VarDecl;
65
66//===----------------------------------------------------------------------===//
67// AST classes for statements.
68//===----------------------------------------------------------------------===//
69
70/// Stmt - This represents one statement.
71///
72class alignas(void *) Stmt {
73public:
74  enum StmtClass {
75    NoStmtClass = 0,
76#define STMT(CLASS, PARENT) CLASS##Class,
77#define STMT_RANGE(BASE, FIRST, LAST) \
78        first##BASE##Constant=FIRST##Class, last##BASE##Constant=LAST##Class,
79#define LAST_STMT_RANGE(BASE, FIRST, LAST) \
80        first##BASE##Constant=FIRST##Class, last##BASE##Constant=LAST##Class
81#define ABSTRACT_STMT(STMT)
82#include "clang/AST/StmtNodes.inc"
83  };
84
85  // Make vanilla 'new' and 'delete' illegal for Stmts.
86protected:
87  friend class ASTStmtReader;
88  friend class ASTStmtWriter;
89
90  void *operator new(size_t bytes) noexcept {
91    llvm_unreachable("Stmts cannot be allocated with regular 'new'.");
92  }
93
94  void operator delete(void *data) noexcept {
95    llvm_unreachable("Stmts cannot be released with regular 'delete'.");
96  }
97
98  //===--- Statement bitfields classes ---===//
99
100  class StmtBitfields {
101    friend class ASTStmtReader;
102    friend class ASTStmtWriter;
103    friend class Stmt;
104
105    /// The statement class.
106    unsigned sClass : 8;
107  };
108  enum { NumStmtBits = 8 };
109
110  class NullStmtBitfields {
111    friend class ASTStmtReader;
112    friend class ASTStmtWriter;
113    friend class NullStmt;
114
115    unsigned : NumStmtBits;
116
117    /// True if the null statement was preceded by an empty macro, e.g:
118    /// @code
119    ///   #define CALL(x)
120    ///   CALL(0);
121    /// @endcode
122    unsigned HasLeadingEmptyMacro : 1;
123
124    /// The location of the semi-colon.
125    SourceLocation SemiLoc;
126  };
127
128  class CompoundStmtBitfields {
129    friend class ASTStmtReader;
130    friend class CompoundStmt;
131
132    unsigned : NumStmtBits;
133
134    /// True if the compound statement has one or more pragmas that set some
135    /// floating-point features.
136    unsigned HasFPFeatures : 1;
137
138    unsigned NumStmts;
139  };
140
141  class LabelStmtBitfields {
142    friend class LabelStmt;
143
144    unsigned : NumStmtBits;
145
146    SourceLocation IdentLoc;
147  };
148
149  class AttributedStmtBitfields {
150    friend class ASTStmtReader;
151    friend class AttributedStmt;
152
153    unsigned : NumStmtBits;
154
155    /// Number of attributes.
156    unsigned NumAttrs : 32 - NumStmtBits;
157
158    /// The location of the attribute.
159    SourceLocation AttrLoc;
160  };
161
162  class IfStmtBitfields {
163    friend class ASTStmtReader;
164    friend class IfStmt;
165
166    unsigned : NumStmtBits;
167
168    /// Whether this is a constexpr if, or a consteval if, or neither.
169    unsigned Kind : 3;
170
171    /// True if this if statement has storage for an else statement.
172    unsigned HasElse : 1;
173
174    /// True if this if statement has storage for a variable declaration.
175    unsigned HasVar : 1;
176
177    /// True if this if statement has storage for an init statement.
178    unsigned HasInit : 1;
179
180    /// The location of the "if".
181    SourceLocation IfLoc;
182  };
183
184  class SwitchStmtBitfields {
185    friend class SwitchStmt;
186
187    unsigned : NumStmtBits;
188
189    /// True if the SwitchStmt has storage for an init statement.
190    unsigned HasInit : 1;
191
192    /// True if the SwitchStmt has storage for a condition variable.
193    unsigned HasVar : 1;
194
195    /// If the SwitchStmt is a switch on an enum value, records whether all
196    /// the enum values were covered by CaseStmts.  The coverage information
197    /// value is meant to be a hint for possible clients.
198    unsigned AllEnumCasesCovered : 1;
199
200    /// The location of the "switch".
201    SourceLocation SwitchLoc;
202  };
203
204  class WhileStmtBitfields {
205    friend class ASTStmtReader;
206    friend class WhileStmt;
207
208    unsigned : NumStmtBits;
209
210    /// True if the WhileStmt has storage for a condition variable.
211    unsigned HasVar : 1;
212
213    /// The location of the "while".
214    SourceLocation WhileLoc;
215  };
216
217  class DoStmtBitfields {
218    friend class DoStmt;
219
220    unsigned : NumStmtBits;
221
222    /// The location of the "do".
223    SourceLocation DoLoc;
224  };
225
226  class ForStmtBitfields {
227    friend class ForStmt;
228
229    unsigned : NumStmtBits;
230
231    /// The location of the "for".
232    SourceLocation ForLoc;
233  };
234
235  class GotoStmtBitfields {
236    friend class GotoStmt;
237    friend class IndirectGotoStmt;
238
239    unsigned : NumStmtBits;
240
241    /// The location of the "goto".
242    SourceLocation GotoLoc;
243  };
244
245  class ContinueStmtBitfields {
246    friend class ContinueStmt;
247
248    unsigned : NumStmtBits;
249
250    /// The location of the "continue".
251    SourceLocation ContinueLoc;
252  };
253
254  class BreakStmtBitfields {
255    friend class BreakStmt;
256
257    unsigned : NumStmtBits;
258
259    /// The location of the "break".
260    SourceLocation BreakLoc;
261  };
262
263  class ReturnStmtBitfields {
264    friend class ReturnStmt;
265
266    unsigned : NumStmtBits;
267
268    /// True if this ReturnStmt has storage for an NRVO candidate.
269    unsigned HasNRVOCandidate : 1;
270
271    /// The location of the "return".
272    SourceLocation RetLoc;
273  };
274
275  class SwitchCaseBitfields {
276    friend class SwitchCase;
277    friend class CaseStmt;
278
279    unsigned : NumStmtBits;
280
281    /// Used by CaseStmt to store whether it is a case statement
282    /// of the form case LHS ... RHS (a GNU extension).
283    unsigned CaseStmtIsGNURange : 1;
284
285    /// The location of the "case" or "default" keyword.
286    SourceLocation KeywordLoc;
287  };
288
289  //===--- Expression bitfields classes ---===//
290
291  class ExprBitfields {
292    friend class ASTStmtReader; // deserialization
293    friend class AtomicExpr; // ctor
294    friend class BlockDeclRefExpr; // ctor
295    friend class CallExpr; // ctor
296    friend class CXXConstructExpr; // ctor
297    friend class CXXDependentScopeMemberExpr; // ctor
298    friend class CXXNewExpr; // ctor
299    friend class CXXUnresolvedConstructExpr; // ctor
300    friend class DeclRefExpr; // computeDependence
301    friend class DependentScopeDeclRefExpr; // ctor
302    friend class DesignatedInitExpr; // ctor
303    friend class Expr;
304    friend class InitListExpr; // ctor
305    friend class ObjCArrayLiteral; // ctor
306    friend class ObjCDictionaryLiteral; // ctor
307    friend class ObjCMessageExpr; // ctor
308    friend class OffsetOfExpr; // ctor
309    friend class OpaqueValueExpr; // ctor
310    friend class OverloadExpr; // ctor
311    friend class ParenListExpr; // ctor
312    friend class PseudoObjectExpr; // ctor
313    friend class ShuffleVectorExpr; // ctor
314
315    unsigned : NumStmtBits;
316
317    unsigned ValueKind : 2;
318    unsigned ObjectKind : 3;
319    unsigned /*ExprDependence*/ Dependent : llvm::BitWidth<ExprDependence>;
320  };
321  enum { NumExprBits = NumStmtBits + 5 + llvm::BitWidth<ExprDependence> };
322
323  class ConstantExprBitfields {
324    friend class ASTStmtReader;
325    friend class ASTStmtWriter;
326    friend class ConstantExpr;
327
328    unsigned : NumExprBits;
329
330    /// The kind of result that is tail-allocated.
331    unsigned ResultKind : 2;
332
333    /// The kind of Result as defined by APValue::Kind.
334    unsigned APValueKind : 4;
335
336    /// When ResultKind == RSK_Int64, true if the tail-allocated integer is
337    /// unsigned.
338    unsigned IsUnsigned : 1;
339
340    /// When ResultKind == RSK_Int64. the BitWidth of the tail-allocated
341    /// integer. 7 bits because it is the minimal number of bits to represent a
342    /// value from 0 to 64 (the size of the tail-allocated integer).
343    unsigned BitWidth : 7;
344
345    /// When ResultKind == RSK_APValue, true if the ASTContext will cleanup the
346    /// tail-allocated APValue.
347    unsigned HasCleanup : 1;
348
349    /// True if this ConstantExpr was created for immediate invocation.
350    unsigned IsImmediateInvocation : 1;
351  };
352
353  class PredefinedExprBitfields {
354    friend class ASTStmtReader;
355    friend class PredefinedExpr;
356
357    unsigned : NumExprBits;
358
359    /// The kind of this PredefinedExpr. One of the enumeration values
360    /// in PredefinedExpr::IdentKind.
361    unsigned Kind : 4;
362
363    /// True if this PredefinedExpr has a trailing "StringLiteral *"
364    /// for the predefined identifier.
365    unsigned HasFunctionName : 1;
366
367    /// The location of this PredefinedExpr.
368    SourceLocation Loc;
369  };
370
371  class DeclRefExprBitfields {
372    friend class ASTStmtReader; // deserialization
373    friend class DeclRefExpr;
374
375    unsigned : NumExprBits;
376
377    unsigned HasQualifier : 1;
378    unsigned HasTemplateKWAndArgsInfo : 1;
379    unsigned HasFoundDecl : 1;
380    unsigned HadMultipleCandidates : 1;
381    unsigned RefersToEnclosingVariableOrCapture : 1;
382    unsigned NonOdrUseReason : 2;
383
384    /// The location of the declaration name itself.
385    SourceLocation Loc;
386  };
387
388
389  class FloatingLiteralBitfields {
390    friend class FloatingLiteral;
391
392    unsigned : NumExprBits;
393
394    static_assert(
395        llvm::APFloat::S_MaxSemantics < 16,
396        "Too many Semantics enum values to fit in bitfield of size 4");
397    unsigned Semantics : 4; // Provides semantics for APFloat construction
398    unsigned IsExact : 1;
399  };
400
401  class StringLiteralBitfields {
402    friend class ASTStmtReader;
403    friend class StringLiteral;
404
405    unsigned : NumExprBits;
406
407    /// The kind of this string literal.
408    /// One of the enumeration values of StringLiteral::StringKind.
409    unsigned Kind : 3;
410
411    /// The width of a single character in bytes. Only values of 1, 2,
412    /// and 4 bytes are supported. StringLiteral::mapCharByteWidth maps
413    /// the target + string kind to the appropriate CharByteWidth.
414    unsigned CharByteWidth : 3;
415
416    unsigned IsPascal : 1;
417
418    /// The number of concatenated token this string is made of.
419    /// This is the number of trailing SourceLocation.
420    unsigned NumConcatenated;
421  };
422
423  class CharacterLiteralBitfields {
424    friend class CharacterLiteral;
425
426    unsigned : NumExprBits;
427
428    unsigned Kind : 3;
429  };
430
431  class UnaryOperatorBitfields {
432    friend class UnaryOperator;
433
434    unsigned : NumExprBits;
435
436    unsigned Opc : 5;
437    unsigned CanOverflow : 1;
438    //
439    /// This is only meaningful for operations on floating point
440    /// types when additional values need to be in trailing storage.
441    /// It is 0 otherwise.
442    unsigned HasFPFeatures : 1;
443
444    SourceLocation Loc;
445  };
446
447  class UnaryExprOrTypeTraitExprBitfields {
448    friend class UnaryExprOrTypeTraitExpr;
449
450    unsigned : NumExprBits;
451
452    unsigned Kind : 3;
453    unsigned IsType : 1; // true if operand is a type, false if an expression.
454  };
455
456  class ArrayOrMatrixSubscriptExprBitfields {
457    friend class ArraySubscriptExpr;
458    friend class MatrixSubscriptExpr;
459
460    unsigned : NumExprBits;
461
462    SourceLocation RBracketLoc;
463  };
464
465  class CallExprBitfields {
466    friend class CallExpr;
467
468    unsigned : NumExprBits;
469
470    unsigned NumPreArgs : 1;
471
472    /// True if the callee of the call expression was found using ADL.
473    unsigned UsesADL : 1;
474
475    /// True if the call expression has some floating-point features.
476    unsigned HasFPFeatures : 1;
477
478    /// Padding used to align OffsetToTrailingObjects to a byte multiple.
479    unsigned : 24 - 3 - NumExprBits;
480
481    /// The offset in bytes from the this pointer to the start of the
482    /// trailing objects belonging to CallExpr. Intentionally byte sized
483    /// for faster access.
484    unsigned OffsetToTrailingObjects : 8;
485  };
486  enum { NumCallExprBits = 32 };
487
488  class MemberExprBitfields {
489    friend class ASTStmtReader;
490    friend class MemberExpr;
491
492    unsigned : NumExprBits;
493
494    /// IsArrow - True if this is "X->F", false if this is "X.F".
495    unsigned IsArrow : 1;
496
497    /// True if this member expression used a nested-name-specifier to
498    /// refer to the member, e.g., "x->Base::f", or found its member via
499    /// a using declaration.  When true, a MemberExprNameQualifier
500    /// structure is allocated immediately after the MemberExpr.
501    unsigned HasQualifierOrFoundDecl : 1;
502
503    /// True if this member expression specified a template keyword
504    /// and/or a template argument list explicitly, e.g., x->f<int>,
505    /// x->template f, x->template f<int>.
506    /// When true, an ASTTemplateKWAndArgsInfo structure and its
507    /// TemplateArguments (if any) are present.
508    unsigned HasTemplateKWAndArgsInfo : 1;
509
510    /// True if this member expression refers to a method that
511    /// was resolved from an overloaded set having size greater than 1.
512    unsigned HadMultipleCandidates : 1;
513
514    /// Value of type NonOdrUseReason indicating why this MemberExpr does
515    /// not constitute an odr-use of the named declaration. Meaningful only
516    /// when naming a static member.
517    unsigned NonOdrUseReason : 2;
518
519    /// This is the location of the -> or . in the expression.
520    SourceLocation OperatorLoc;
521  };
522
523  class CastExprBitfields {
524    friend class CastExpr;
525    friend class ImplicitCastExpr;
526
527    unsigned : NumExprBits;
528
529    unsigned Kind : 7;
530    unsigned PartOfExplicitCast : 1; // Only set for ImplicitCastExpr.
531
532    /// True if the call expression has some floating-point features.
533    unsigned HasFPFeatures : 1;
534
535    /// The number of CXXBaseSpecifiers in the cast. 14 bits would be enough
536    /// here. ([implimits] Direct and indirect base classes [16384]).
537    unsigned BasePathSize;
538  };
539
540  class BinaryOperatorBitfields {
541    friend class BinaryOperator;
542
543    unsigned : NumExprBits;
544
545    unsigned Opc : 6;
546
547    /// This is only meaningful for operations on floating point
548    /// types when additional values need to be in trailing storage.
549    /// It is 0 otherwise.
550    unsigned HasFPFeatures : 1;
551
552    SourceLocation OpLoc;
553  };
554
555  class InitListExprBitfields {
556    friend class InitListExpr;
557
558    unsigned : NumExprBits;
559
560    /// Whether this initializer list originally had a GNU array-range
561    /// designator in it. This is a temporary marker used by CodeGen.
562    unsigned HadArrayRangeDesignator : 1;
563  };
564
565  class ParenListExprBitfields {
566    friend class ASTStmtReader;
567    friend class ParenListExpr;
568
569    unsigned : NumExprBits;
570
571    /// The number of expressions in the paren list.
572    unsigned NumExprs;
573  };
574
575  class GenericSelectionExprBitfields {
576    friend class ASTStmtReader;
577    friend class GenericSelectionExpr;
578
579    unsigned : NumExprBits;
580
581    /// The location of the "_Generic".
582    SourceLocation GenericLoc;
583  };
584
585  class PseudoObjectExprBitfields {
586    friend class ASTStmtReader; // deserialization
587    friend class PseudoObjectExpr;
588
589    unsigned : NumExprBits;
590
591    // These don't need to be particularly wide, because they're
592    // strictly limited by the forms of expressions we permit.
593    unsigned NumSubExprs : 8;
594    unsigned ResultIndex : 32 - 8 - NumExprBits;
595  };
596
597  class SourceLocExprBitfields {
598    friend class ASTStmtReader;
599    friend class SourceLocExpr;
600
601    unsigned : NumExprBits;
602
603    /// The kind of source location builtin represented by the SourceLocExpr.
604    /// Ex. __builtin_LINE, __builtin_FUNCTION, etc.
605    unsigned Kind : 3;
606  };
607
608  class StmtExprBitfields {
609    friend class ASTStmtReader;
610    friend class StmtExpr;
611
612    unsigned : NumExprBits;
613
614    /// The number of levels of template parameters enclosing this statement
615    /// expression. Used to determine if a statement expression remains
616    /// dependent after instantiation.
617    unsigned TemplateDepth;
618  };
619
620  //===--- C++ Expression bitfields classes ---===//
621
622  class CXXOperatorCallExprBitfields {
623    friend class ASTStmtReader;
624    friend class CXXOperatorCallExpr;
625
626    unsigned : NumCallExprBits;
627
628    /// The kind of this overloaded operator. One of the enumerator
629    /// value of OverloadedOperatorKind.
630    unsigned OperatorKind : 6;
631  };
632
633  class CXXRewrittenBinaryOperatorBitfields {
634    friend class ASTStmtReader;
635    friend class CXXRewrittenBinaryOperator;
636
637    unsigned : NumCallExprBits;
638
639    unsigned IsReversed : 1;
640  };
641
642  class CXXBoolLiteralExprBitfields {
643    friend class CXXBoolLiteralExpr;
644
645    unsigned : NumExprBits;
646
647    /// The value of the boolean literal.
648    unsigned Value : 1;
649
650    /// The location of the boolean literal.
651    SourceLocation Loc;
652  };
653
654  class CXXNullPtrLiteralExprBitfields {
655    friend class CXXNullPtrLiteralExpr;
656
657    unsigned : NumExprBits;
658
659    /// The location of the null pointer literal.
660    SourceLocation Loc;
661  };
662
663  class CXXThisExprBitfields {
664    friend class CXXThisExpr;
665
666    unsigned : NumExprBits;
667
668    /// Whether this is an implicit "this".
669    unsigned IsImplicit : 1;
670
671    /// The location of the "this".
672    SourceLocation Loc;
673  };
674
675  class CXXThrowExprBitfields {
676    friend class ASTStmtReader;
677    friend class CXXThrowExpr;
678
679    unsigned : NumExprBits;
680
681    /// Whether the thrown variable (if any) is in scope.
682    unsigned IsThrownVariableInScope : 1;
683
684    /// The location of the "throw".
685    SourceLocation ThrowLoc;
686  };
687
688  class CXXDefaultArgExprBitfields {
689    friend class ASTStmtReader;
690    friend class CXXDefaultArgExpr;
691
692    unsigned : NumExprBits;
693
694    /// Whether this CXXDefaultArgExpr rewrote its argument and stores a copy.
695    unsigned HasRewrittenInit : 1;
696
697    /// The location where the default argument expression was used.
698    SourceLocation Loc;
699  };
700
701  class CXXDefaultInitExprBitfields {
702    friend class ASTStmtReader;
703    friend class CXXDefaultInitExpr;
704
705    unsigned : NumExprBits;
706
707    /// Whether this CXXDefaultInitExprBitfields rewrote its argument and stores
708    /// a copy.
709    unsigned HasRewrittenInit : 1;
710
711    /// The location where the default initializer expression was used.
712    SourceLocation Loc;
713  };
714
715  class CXXScalarValueInitExprBitfields {
716    friend class ASTStmtReader;
717    friend class CXXScalarValueInitExpr;
718
719    unsigned : NumExprBits;
720
721    SourceLocation RParenLoc;
722  };
723
724  class CXXNewExprBitfields {
725    friend class ASTStmtReader;
726    friend class ASTStmtWriter;
727    friend class CXXNewExpr;
728
729    unsigned : NumExprBits;
730
731    /// Was the usage ::new, i.e. is the global new to be used?
732    unsigned IsGlobalNew : 1;
733
734    /// Do we allocate an array? If so, the first trailing "Stmt *" is the
735    /// size expression.
736    unsigned IsArray : 1;
737
738    /// Should the alignment be passed to the allocation function?
739    unsigned ShouldPassAlignment : 1;
740
741    /// If this is an array allocation, does the usual deallocation
742    /// function for the allocated type want to know the allocated size?
743    unsigned UsualArrayDeleteWantsSize : 1;
744
745    /// What kind of initializer do we have? Could be none, parens, or braces.
746    /// In storage, we distinguish between "none, and no initializer expr", and
747    /// "none, but an implicit initializer expr".
748    unsigned StoredInitializationStyle : 2;
749
750    /// True if the allocated type was expressed as a parenthesized type-id.
751    unsigned IsParenTypeId : 1;
752
753    /// The number of placement new arguments.
754    unsigned NumPlacementArgs;
755  };
756
757  class CXXDeleteExprBitfields {
758    friend class ASTStmtReader;
759    friend class CXXDeleteExpr;
760
761    unsigned : NumExprBits;
762
763    /// Is this a forced global delete, i.e. "::delete"?
764    unsigned GlobalDelete : 1;
765
766    /// Is this the array form of delete, i.e. "delete[]"?
767    unsigned ArrayForm : 1;
768
769    /// ArrayFormAsWritten can be different from ArrayForm if 'delete' is
770    /// applied to pointer-to-array type (ArrayFormAsWritten will be false
771    /// while ArrayForm will be true).
772    unsigned ArrayFormAsWritten : 1;
773
774    /// Does the usual deallocation function for the element type require
775    /// a size_t argument?
776    unsigned UsualArrayDeleteWantsSize : 1;
777
778    /// Location of the expression.
779    SourceLocation Loc;
780  };
781
782  class TypeTraitExprBitfields {
783    friend class ASTStmtReader;
784    friend class ASTStmtWriter;
785    friend class TypeTraitExpr;
786
787    unsigned : NumExprBits;
788
789    /// The kind of type trait, which is a value of a TypeTrait enumerator.
790    unsigned Kind : 8;
791
792    /// If this expression is not value-dependent, this indicates whether
793    /// the trait evaluated true or false.
794    unsigned Value : 1;
795
796    /// The number of arguments to this type trait. According to [implimits]
797    /// 8 bits would be enough, but we require (and test for) at least 16 bits
798    /// to mirror FunctionType.
799    unsigned NumArgs;
800  };
801
802  class DependentScopeDeclRefExprBitfields {
803    friend class ASTStmtReader;
804    friend class ASTStmtWriter;
805    friend class DependentScopeDeclRefExpr;
806
807    unsigned : NumExprBits;
808
809    /// Whether the name includes info for explicit template
810    /// keyword and arguments.
811    unsigned HasTemplateKWAndArgsInfo : 1;
812  };
813
814  class CXXConstructExprBitfields {
815    friend class ASTStmtReader;
816    friend class CXXConstructExpr;
817
818    unsigned : NumExprBits;
819
820    unsigned Elidable : 1;
821    unsigned HadMultipleCandidates : 1;
822    unsigned ListInitialization : 1;
823    unsigned StdInitListInitialization : 1;
824    unsigned ZeroInitialization : 1;
825    unsigned ConstructionKind : 3;
826
827    SourceLocation Loc;
828  };
829
830  class ExprWithCleanupsBitfields {
831    friend class ASTStmtReader; // deserialization
832    friend class ExprWithCleanups;
833
834    unsigned : NumExprBits;
835
836    // When false, it must not have side effects.
837    unsigned CleanupsHaveSideEffects : 1;
838
839    unsigned NumObjects : 32 - 1 - NumExprBits;
840  };
841
842  class CXXUnresolvedConstructExprBitfields {
843    friend class ASTStmtReader;
844    friend class CXXUnresolvedConstructExpr;
845
846    unsigned : NumExprBits;
847
848    /// The number of arguments used to construct the type.
849    unsigned NumArgs;
850  };
851
852  class CXXDependentScopeMemberExprBitfields {
853    friend class ASTStmtReader;
854    friend class CXXDependentScopeMemberExpr;
855
856    unsigned : NumExprBits;
857
858    /// Whether this member expression used the '->' operator or
859    /// the '.' operator.
860    unsigned IsArrow : 1;
861
862    /// Whether this member expression has info for explicit template
863    /// keyword and arguments.
864    unsigned HasTemplateKWAndArgsInfo : 1;
865
866    /// See getFirstQualifierFoundInScope() and the comment listing
867    /// the trailing objects.
868    unsigned HasFirstQualifierFoundInScope : 1;
869
870    /// The location of the '->' or '.' operator.
871    SourceLocation OperatorLoc;
872  };
873
874  class OverloadExprBitfields {
875    friend class ASTStmtReader;
876    friend class OverloadExpr;
877
878    unsigned : NumExprBits;
879
880    /// Whether the name includes info for explicit template
881    /// keyword and arguments.
882    unsigned HasTemplateKWAndArgsInfo : 1;
883
884    /// Padding used by the derived classes to store various bits. If you
885    /// need to add some data here, shrink this padding and add your data
886    /// above. NumOverloadExprBits also needs to be updated.
887    unsigned : 32 - NumExprBits - 1;
888
889    /// The number of results.
890    unsigned NumResults;
891  };
892  enum { NumOverloadExprBits = NumExprBits + 1 };
893
894  class UnresolvedLookupExprBitfields {
895    friend class ASTStmtReader;
896    friend class UnresolvedLookupExpr;
897
898    unsigned : NumOverloadExprBits;
899
900    /// True if these lookup results should be extended by
901    /// argument-dependent lookup if this is the operand of a function call.
902    unsigned RequiresADL : 1;
903
904    /// True if these lookup results are overloaded.  This is pretty trivially
905    /// rederivable if we urgently need to kill this field.
906    unsigned Overloaded : 1;
907  };
908  static_assert(sizeof(UnresolvedLookupExprBitfields) <= 4,
909                "UnresolvedLookupExprBitfields must be <= than 4 bytes to"
910                "avoid trashing OverloadExprBitfields::NumResults!");
911
912  class UnresolvedMemberExprBitfields {
913    friend class ASTStmtReader;
914    friend class UnresolvedMemberExpr;
915
916    unsigned : NumOverloadExprBits;
917
918    /// Whether this member expression used the '->' operator or
919    /// the '.' operator.
920    unsigned IsArrow : 1;
921
922    /// Whether the lookup results contain an unresolved using declaration.
923    unsigned HasUnresolvedUsing : 1;
924  };
925  static_assert(sizeof(UnresolvedMemberExprBitfields) <= 4,
926                "UnresolvedMemberExprBitfields must be <= than 4 bytes to"
927                "avoid trashing OverloadExprBitfields::NumResults!");
928
929  class CXXNoexceptExprBitfields {
930    friend class ASTStmtReader;
931    friend class CXXNoexceptExpr;
932
933    unsigned : NumExprBits;
934
935    unsigned Value : 1;
936  };
937
938  class SubstNonTypeTemplateParmExprBitfields {
939    friend class ASTStmtReader;
940    friend class SubstNonTypeTemplateParmExpr;
941
942    unsigned : NumExprBits;
943
944    /// The location of the non-type template parameter reference.
945    SourceLocation NameLoc;
946  };
947
948  class LambdaExprBitfields {
949    friend class ASTStmtReader;
950    friend class ASTStmtWriter;
951    friend class LambdaExpr;
952
953    unsigned : NumExprBits;
954
955    /// The default capture kind, which is a value of type
956    /// LambdaCaptureDefault.
957    unsigned CaptureDefault : 2;
958
959    /// Whether this lambda had an explicit parameter list vs. an
960    /// implicit (and empty) parameter list.
961    unsigned ExplicitParams : 1;
962
963    /// Whether this lambda had the result type explicitly specified.
964    unsigned ExplicitResultType : 1;
965
966    /// The number of captures.
967    unsigned NumCaptures : 16;
968  };
969
970  class RequiresExprBitfields {
971    friend class ASTStmtReader;
972    friend class ASTStmtWriter;
973    friend class RequiresExpr;
974
975    unsigned : NumExprBits;
976
977    unsigned IsSatisfied : 1;
978    SourceLocation RequiresKWLoc;
979  };
980
981  //===--- C++ Coroutines TS bitfields classes ---===//
982
983  class CoawaitExprBitfields {
984    friend class CoawaitExpr;
985
986    unsigned : NumExprBits;
987
988    unsigned IsImplicit : 1;
989  };
990
991  //===--- Obj-C Expression bitfields classes ---===//
992
993  class ObjCIndirectCopyRestoreExprBitfields {
994    friend class ObjCIndirectCopyRestoreExpr;
995
996    unsigned : NumExprBits;
997
998    unsigned ShouldCopy : 1;
999  };
1000
1001  //===--- Clang Extensions bitfields classes ---===//
1002
1003  class OpaqueValueExprBitfields {
1004    friend class ASTStmtReader;
1005    friend class OpaqueValueExpr;
1006
1007    unsigned : NumExprBits;
1008
1009    /// The OVE is a unique semantic reference to its source expression if this
1010    /// bit is set to true.
1011    unsigned IsUnique : 1;
1012
1013    SourceLocation Loc;
1014  };
1015
1016  union {
1017    // Same order as in StmtNodes.td.
1018    // Statements
1019    StmtBitfields StmtBits;
1020    NullStmtBitfields NullStmtBits;
1021    CompoundStmtBitfields CompoundStmtBits;
1022    LabelStmtBitfields LabelStmtBits;
1023    AttributedStmtBitfields AttributedStmtBits;
1024    IfStmtBitfields IfStmtBits;
1025    SwitchStmtBitfields SwitchStmtBits;
1026    WhileStmtBitfields WhileStmtBits;
1027    DoStmtBitfields DoStmtBits;
1028    ForStmtBitfields ForStmtBits;
1029    GotoStmtBitfields GotoStmtBits;
1030    ContinueStmtBitfields ContinueStmtBits;
1031    BreakStmtBitfields BreakStmtBits;
1032    ReturnStmtBitfields ReturnStmtBits;
1033    SwitchCaseBitfields SwitchCaseBits;
1034
1035    // Expressions
1036    ExprBitfields ExprBits;
1037    ConstantExprBitfields ConstantExprBits;
1038    PredefinedExprBitfields PredefinedExprBits;
1039    DeclRefExprBitfields DeclRefExprBits;
1040    FloatingLiteralBitfields FloatingLiteralBits;
1041    StringLiteralBitfields StringLiteralBits;
1042    CharacterLiteralBitfields CharacterLiteralBits;
1043    UnaryOperatorBitfields UnaryOperatorBits;
1044    UnaryExprOrTypeTraitExprBitfields UnaryExprOrTypeTraitExprBits;
1045    ArrayOrMatrixSubscriptExprBitfields ArrayOrMatrixSubscriptExprBits;
1046    CallExprBitfields CallExprBits;
1047    MemberExprBitfields MemberExprBits;
1048    CastExprBitfields CastExprBits;
1049    BinaryOperatorBitfields BinaryOperatorBits;
1050    InitListExprBitfields InitListExprBits;
1051    ParenListExprBitfields ParenListExprBits;
1052    GenericSelectionExprBitfields GenericSelectionExprBits;
1053    PseudoObjectExprBitfields PseudoObjectExprBits;
1054    SourceLocExprBitfields SourceLocExprBits;
1055
1056    // GNU Extensions.
1057    StmtExprBitfields StmtExprBits;
1058
1059    // C++ Expressions
1060    CXXOperatorCallExprBitfields CXXOperatorCallExprBits;
1061    CXXRewrittenBinaryOperatorBitfields CXXRewrittenBinaryOperatorBits;
1062    CXXBoolLiteralExprBitfields CXXBoolLiteralExprBits;
1063    CXXNullPtrLiteralExprBitfields CXXNullPtrLiteralExprBits;
1064    CXXThisExprBitfields CXXThisExprBits;
1065    CXXThrowExprBitfields CXXThrowExprBits;
1066    CXXDefaultArgExprBitfields CXXDefaultArgExprBits;
1067    CXXDefaultInitExprBitfields CXXDefaultInitExprBits;
1068    CXXScalarValueInitExprBitfields CXXScalarValueInitExprBits;
1069    CXXNewExprBitfields CXXNewExprBits;
1070    CXXDeleteExprBitfields CXXDeleteExprBits;
1071    TypeTraitExprBitfields TypeTraitExprBits;
1072    DependentScopeDeclRefExprBitfields DependentScopeDeclRefExprBits;
1073    CXXConstructExprBitfields CXXConstructExprBits;
1074    ExprWithCleanupsBitfields ExprWithCleanupsBits;
1075    CXXUnresolvedConstructExprBitfields CXXUnresolvedConstructExprBits;
1076    CXXDependentScopeMemberExprBitfields CXXDependentScopeMemberExprBits;
1077    OverloadExprBitfields OverloadExprBits;
1078    UnresolvedLookupExprBitfields UnresolvedLookupExprBits;
1079    UnresolvedMemberExprBitfields UnresolvedMemberExprBits;
1080    CXXNoexceptExprBitfields CXXNoexceptExprBits;
1081    SubstNonTypeTemplateParmExprBitfields SubstNonTypeTemplateParmExprBits;
1082    LambdaExprBitfields LambdaExprBits;
1083    RequiresExprBitfields RequiresExprBits;
1084
1085    // C++ Coroutines TS expressions
1086    CoawaitExprBitfields CoawaitBits;
1087
1088    // Obj-C Expressions
1089    ObjCIndirectCopyRestoreExprBitfields ObjCIndirectCopyRestoreExprBits;
1090
1091    // Clang Extensions
1092    OpaqueValueExprBitfields OpaqueValueExprBits;
1093  };
1094
1095public:
1096  // Only allow allocation of Stmts using the allocator in ASTContext
1097  // or by doing a placement new.
1098  void* operator new(size_t bytes, const ASTContext& C,
1099                     unsigned alignment = 8);
1100
1101  void* operator new(size_t bytes, const ASTContext* C,
1102                     unsigned alignment = 8) {
1103    return operator new(bytes, *C, alignment);
1104  }
1105
1106  void *operator new(size_t bytes, void *mem) noexcept { return mem; }
1107
1108  void operator delete(void *, const ASTContext &, unsigned) noexcept {}
1109  void operator delete(void *, const ASTContext *, unsigned) noexcept {}
1110  void operator delete(void *, size_t) noexcept {}
1111  void operator delete(void *, void *) noexcept {}
1112
1113public:
1114  /// A placeholder type used to construct an empty shell of a
1115  /// type, that will be filled in later (e.g., by some
1116  /// de-serialization).
1117  struct EmptyShell {};
1118
1119  /// The likelihood of a branch being taken.
1120  enum Likelihood {
1121    LH_Unlikely = -1, ///< Branch has the [[unlikely]] attribute.
1122    LH_None,          ///< No attribute set or branches of the IfStmt have
1123                      ///< the same attribute.
1124    LH_Likely         ///< Branch has the [[likely]] attribute.
1125  };
1126
1127protected:
1128  /// Iterator for iterating over Stmt * arrays that contain only T *.
1129  ///
1130  /// This is needed because AST nodes use Stmt* arrays to store
1131  /// references to children (to be compatible with StmtIterator).
1132  template<typename T, typename TPtr = T *, typename StmtPtr = Stmt *>
1133  struct CastIterator
1134      : llvm::iterator_adaptor_base<CastIterator<T, TPtr, StmtPtr>, StmtPtr *,
1135                                    std::random_access_iterator_tag, TPtr> {
1136    using Base = typename CastIterator::iterator_adaptor_base;
1137
1138    CastIterator() : Base(nullptr) {}
1139    CastIterator(StmtPtr *I) : Base(I) {}
1140
1141    typename Base::value_type operator*() const {
1142      return cast_or_null<T>(*this->I);
1143    }
1144  };
1145
1146  /// Const iterator for iterating over Stmt * arrays that contain only T *.
1147  template <typename T>
1148  using ConstCastIterator = CastIterator<T, const T *const, const Stmt *const>;
1149
1150  using ExprIterator = CastIterator<Expr>;
1151  using ConstExprIterator = ConstCastIterator<Expr>;
1152
1153private:
1154  /// Whether statistic collection is enabled.
1155  static bool StatisticsEnabled;
1156
1157protected:
1158  /// Construct an empty statement.
1159  explicit Stmt(StmtClass SC, EmptyShell) : Stmt(SC) {}
1160
1161public:
1162  Stmt() = delete;
1163  Stmt(const Stmt &) = delete;
1164  Stmt(Stmt &&) = delete;
1165  Stmt &operator=(const Stmt &) = delete;
1166  Stmt &operator=(Stmt &&) = delete;
1167
1168  Stmt(StmtClass SC) {
1169    static_assert(sizeof(*this) <= 8,
1170                  "changing bitfields changed sizeof(Stmt)");
1171    static_assert(sizeof(*this) % alignof(void *) == 0,
1172                  "Insufficient alignment!");
1173    StmtBits.sClass = SC;
1174    if (StatisticsEnabled) Stmt::addStmtClass(SC);
1175  }
1176
1177  StmtClass getStmtClass() const {
1178    return static_cast<StmtClass>(StmtBits.sClass);
1179  }
1180
1181  const char *getStmtClassName() const;
1182
1183  /// SourceLocation tokens are not useful in isolation - they are low level
1184  /// value objects created/interpreted by SourceManager. We assume AST
1185  /// clients will have a pointer to the respective SourceManager.
1186  SourceRange getSourceRange() const LLVM_READONLY;
1187  SourceLocation getBeginLoc() const LLVM_READONLY;
1188  SourceLocation getEndLoc() const LLVM_READONLY;
1189
1190  // global temp stats (until we have a per-module visitor)
1191  static void addStmtClass(const StmtClass s);
1192  static void EnableStatistics();
1193  static void PrintStats();
1194
1195  /// \returns the likelihood of a set of attributes.
1196  static Likelihood getLikelihood(ArrayRef<const Attr *> Attrs);
1197
1198  /// \returns the likelihood of a statement.
1199  static Likelihood getLikelihood(const Stmt *S);
1200
1201  /// \returns the likelihood attribute of a statement.
1202  static const Attr *getLikelihoodAttr(const Stmt *S);
1203
1204  /// \returns the likelihood of the 'then' branch of an 'if' statement. The
1205  /// 'else' branch is required to determine whether both branches specify the
1206  /// same likelihood, which affects the result.
1207  static Likelihood getLikelihood(const Stmt *Then, const Stmt *Else);
1208
1209  /// \returns whether the likelihood of the branches of an if statement are
1210  /// conflicting. When the first element is \c true there's a conflict and
1211  /// the Attr's are the conflicting attributes of the Then and Else Stmt.
1212  static std::tuple<bool, const Attr *, const Attr *>
1213  determineLikelihoodConflict(const Stmt *Then, const Stmt *Else);
1214
1215  /// Dumps the specified AST fragment and all subtrees to
1216  /// \c llvm::errs().
1217  void dump() const;
1218  void dump(raw_ostream &OS, const ASTContext &Context) const;
1219
1220  /// \return Unique reproducible object identifier
1221  int64_t getID(const ASTContext &Context) const;
1222
1223  /// dumpColor - same as dump(), but forces color highlighting.
1224  void dumpColor() const;
1225
1226  /// dumpPretty/printPretty - These two methods do a "pretty print" of the AST
1227  /// back to its original source language syntax.
1228  void dumpPretty(const ASTContext &Context) const;
1229  void printPretty(raw_ostream &OS, PrinterHelper *Helper,
1230                   const PrintingPolicy &Policy, unsigned Indentation = 0,
1231                   StringRef NewlineSymbol = "\n",
1232                   const ASTContext *Context = nullptr) const;
1233  void printPrettyControlled(raw_ostream &OS, PrinterHelper *Helper,
1234                             const PrintingPolicy &Policy,
1235                             unsigned Indentation = 0,
1236                             StringRef NewlineSymbol = "\n",
1237                             const ASTContext *Context = nullptr) const;
1238
1239  /// Pretty-prints in JSON format.
1240  void printJson(raw_ostream &Out, PrinterHelper *Helper,
1241                 const PrintingPolicy &Policy, bool AddQuotes) const;
1242
1243  /// viewAST - Visualize an AST rooted at this Stmt* using GraphViz.  Only
1244  ///   works on systems with GraphViz (Mac OS X) or dot+gv installed.
1245  void viewAST() const;
1246
1247  /// Skip no-op (attributed, compound) container stmts and skip captured
1248  /// stmt at the top, if \a IgnoreCaptured is true.
1249  Stmt *IgnoreContainers(bool IgnoreCaptured = false);
1250  const Stmt *IgnoreContainers(bool IgnoreCaptured = false) const {
1251    return const_cast<Stmt *>(this)->IgnoreContainers(IgnoreCaptured);
1252  }
1253
1254  const Stmt *stripLabelLikeStatements() const;
1255  Stmt *stripLabelLikeStatements() {
1256    return const_cast<Stmt*>(
1257      const_cast<const Stmt*>(this)->stripLabelLikeStatements());
1258  }
1259
1260  /// Child Iterators: All subclasses must implement 'children'
1261  /// to permit easy iteration over the substatements/subexpressions of an
1262  /// AST node.  This permits easy iteration over all nodes in the AST.
1263  using child_iterator = StmtIterator;
1264  using const_child_iterator = ConstStmtIterator;
1265
1266  using child_range = llvm::iterator_range<child_iterator>;
1267  using const_child_range = llvm::iterator_range<const_child_iterator>;
1268
1269  child_range children();
1270
1271  const_child_range children() const {
1272    auto Children = const_cast<Stmt *>(this)->children();
1273    return const_child_range(Children.begin(), Children.end());
1274  }
1275
1276  child_iterator child_begin() { return children().begin(); }
1277  child_iterator child_end() { return children().end(); }
1278
1279  const_child_iterator child_begin() const { return children().begin(); }
1280  const_child_iterator child_end() const { return children().end(); }
1281
1282  /// Produce a unique representation of the given statement.
1283  ///
1284  /// \param ID once the profiling operation is complete, will contain
1285  /// the unique representation of the given statement.
1286  ///
1287  /// \param Context the AST context in which the statement resides
1288  ///
1289  /// \param Canonical whether the profile should be based on the canonical
1290  /// representation of this statement (e.g., where non-type template
1291  /// parameters are identified by index/level rather than their
1292  /// declaration pointers) or the exact representation of the statement as
1293  /// written in the source.
1294  void Profile(llvm::FoldingSetNodeID &ID, const ASTContext &Context,
1295               bool Canonical) const;
1296
1297  /// Calculate a unique representation for a statement that is
1298  /// stable across compiler invocations.
1299  ///
1300  /// \param ID profile information will be stored in ID.
1301  ///
1302  /// \param Hash an ODRHash object which will be called where pointers would
1303  /// have been used in the Profile function.
1304  void ProcessODRHash(llvm::FoldingSetNodeID &ID, ODRHash& Hash) const;
1305};
1306
1307/// DeclStmt - Adaptor class for mixing declarations with statements and
1308/// expressions. For example, CompoundStmt mixes statements, expressions
1309/// and declarations (variables, types). Another example is ForStmt, where
1310/// the first statement can be an expression or a declaration.
1311class DeclStmt : public Stmt {
1312  DeclGroupRef DG;
1313  SourceLocation StartLoc, EndLoc;
1314
1315public:
1316  DeclStmt(DeclGroupRef dg, SourceLocation startLoc, SourceLocation endLoc)
1317      : Stmt(DeclStmtClass), DG(dg), StartLoc(startLoc), EndLoc(endLoc) {}
1318
1319  /// Build an empty declaration statement.
1320  explicit DeclStmt(EmptyShell Empty) : Stmt(DeclStmtClass, Empty) {}
1321
1322  /// isSingleDecl - This method returns true if this DeclStmt refers
1323  /// to a single Decl.
1324  bool isSingleDecl() const { return DG.isSingleDecl(); }
1325
1326  const Decl *getSingleDecl() const { return DG.getSingleDecl(); }
1327  Decl *getSingleDecl() { return DG.getSingleDecl(); }
1328
1329  const DeclGroupRef getDeclGroup() const { return DG; }
1330  DeclGroupRef getDeclGroup() { return DG; }
1331  void setDeclGroup(DeclGroupRef DGR) { DG = DGR; }
1332
1333  void setStartLoc(SourceLocation L) { StartLoc = L; }
1334  SourceLocation getEndLoc() const { return EndLoc; }
1335  void setEndLoc(SourceLocation L) { EndLoc = L; }
1336
1337  SourceLocation getBeginLoc() const LLVM_READONLY { return StartLoc; }
1338
1339  static bool classof(const Stmt *T) {
1340    return T->getStmtClass() == DeclStmtClass;
1341  }
1342
1343  // Iterators over subexpressions.
1344  child_range children() {
1345    return child_range(child_iterator(DG.begin(), DG.end()),
1346                       child_iterator(DG.end(), DG.end()));
1347  }
1348
1349  const_child_range children() const {
1350    auto Children = const_cast<DeclStmt *>(this)->children();
1351    return const_child_range(Children);
1352  }
1353
1354  using decl_iterator = DeclGroupRef::iterator;
1355  using const_decl_iterator = DeclGroupRef::const_iterator;
1356  using decl_range = llvm::iterator_range<decl_iterator>;
1357  using decl_const_range = llvm::iterator_range<const_decl_iterator>;
1358
1359  decl_range decls() { return decl_range(decl_begin(), decl_end()); }
1360
1361  decl_const_range decls() const {
1362    return decl_const_range(decl_begin(), decl_end());
1363  }
1364
1365  decl_iterator decl_begin() { return DG.begin(); }
1366  decl_iterator decl_end() { return DG.end(); }
1367  const_decl_iterator decl_begin() const { return DG.begin(); }
1368  const_decl_iterator decl_end() const { return DG.end(); }
1369
1370  using reverse_decl_iterator = std::reverse_iterator<decl_iterator>;
1371
1372  reverse_decl_iterator decl_rbegin() {
1373    return reverse_decl_iterator(decl_end());
1374  }
1375
1376  reverse_decl_iterator decl_rend() {
1377    return reverse_decl_iterator(decl_begin());
1378  }
1379};
1380
1381/// NullStmt - This is the null statement ";": C99 6.8.3p3.
1382///
1383class NullStmt : public Stmt {
1384public:
1385  NullStmt(SourceLocation L, bool hasLeadingEmptyMacro = false)
1386      : Stmt(NullStmtClass) {
1387    NullStmtBits.HasLeadingEmptyMacro = hasLeadingEmptyMacro;
1388    setSemiLoc(L);
1389  }
1390
1391  /// Build an empty null statement.
1392  explicit NullStmt(EmptyShell Empty) : Stmt(NullStmtClass, Empty) {}
1393
1394  SourceLocation getSemiLoc() const { return NullStmtBits.SemiLoc; }
1395  void setSemiLoc(SourceLocation L) { NullStmtBits.SemiLoc = L; }
1396
1397  bool hasLeadingEmptyMacro() const {
1398    return NullStmtBits.HasLeadingEmptyMacro;
1399  }
1400
1401  SourceLocation getBeginLoc() const { return getSemiLoc(); }
1402  SourceLocation getEndLoc() const { return getSemiLoc(); }
1403
1404  static bool classof(const Stmt *T) {
1405    return T->getStmtClass() == NullStmtClass;
1406  }
1407
1408  child_range children() {
1409    return child_range(child_iterator(), child_iterator());
1410  }
1411
1412  const_child_range children() const {
1413    return const_child_range(const_child_iterator(), const_child_iterator());
1414  }
1415};
1416
1417/// CompoundStmt - This represents a group of statements like { stmt stmt }.
1418class CompoundStmt final
1419    : public Stmt,
1420      private llvm::TrailingObjects<CompoundStmt, Stmt *, FPOptionsOverride> {
1421  friend class ASTStmtReader;
1422  friend TrailingObjects;
1423
1424  /// The location of the opening "{".
1425  SourceLocation LBraceLoc;
1426
1427  /// The location of the closing "}".
1428  SourceLocation RBraceLoc;
1429
1430  CompoundStmt(ArrayRef<Stmt *> Stmts, FPOptionsOverride FPFeatures,
1431               SourceLocation LB, SourceLocation RB);
1432  explicit CompoundStmt(EmptyShell Empty) : Stmt(CompoundStmtClass, Empty) {}
1433
1434  void setStmts(ArrayRef<Stmt *> Stmts);
1435
1436  /// Set FPOptionsOverride in trailing storage. Used only by Serialization.
1437  void setStoredFPFeatures(FPOptionsOverride F) {
1438    assert(hasStoredFPFeatures());
1439    *getTrailingObjects<FPOptionsOverride>() = F;
1440  }
1441
1442  size_t numTrailingObjects(OverloadToken<Stmt *>) const {
1443    return CompoundStmtBits.NumStmts;
1444  }
1445
1446public:
1447  static CompoundStmt *Create(const ASTContext &C, ArrayRef<Stmt *> Stmts,
1448                              FPOptionsOverride FPFeatures, SourceLocation LB,
1449                              SourceLocation RB);
1450
1451  // Build an empty compound statement with a location.
1452  explicit CompoundStmt(SourceLocation Loc)
1453      : Stmt(CompoundStmtClass), LBraceLoc(Loc), RBraceLoc(Loc) {
1454    CompoundStmtBits.NumStmts = 0;
1455    CompoundStmtBits.HasFPFeatures = 0;
1456  }
1457
1458  // Build an empty compound statement.
1459  static CompoundStmt *CreateEmpty(const ASTContext &C, unsigned NumStmts,
1460                                   bool HasFPFeatures);
1461
1462  bool body_empty() const { return CompoundStmtBits.NumStmts == 0; }
1463  unsigned size() const { return CompoundStmtBits.NumStmts; }
1464
1465  bool hasStoredFPFeatures() const { return CompoundStmtBits.HasFPFeatures; }
1466
1467  /// Get FPOptionsOverride from trailing storage.
1468  FPOptionsOverride getStoredFPFeatures() const {
1469    assert(hasStoredFPFeatures());
1470    return *getTrailingObjects<FPOptionsOverride>();
1471  }
1472
1473  using body_iterator = Stmt **;
1474  using body_range = llvm::iterator_range<body_iterator>;
1475
1476  body_range body() { return body_range(body_begin(), body_end()); }
1477  body_iterator body_begin() { return getTrailingObjects<Stmt *>(); }
1478  body_iterator body_end() { return body_begin() + size(); }
1479  Stmt *body_front() { return !body_empty() ? body_begin()[0] : nullptr; }
1480
1481  Stmt *body_back() {
1482    return !body_empty() ? body_begin()[size() - 1] : nullptr;
1483  }
1484
1485  using const_body_iterator = Stmt *const *;
1486  using body_const_range = llvm::iterator_range<const_body_iterator>;
1487
1488  body_const_range body() const {
1489    return body_const_range(body_begin(), body_end());
1490  }
1491
1492  const_body_iterator body_begin() const {
1493    return getTrailingObjects<Stmt *>();
1494  }
1495
1496  const_body_iterator body_end() const { return body_begin() + size(); }
1497
1498  const Stmt *body_front() const {
1499    return !body_empty() ? body_begin()[0] : nullptr;
1500  }
1501
1502  const Stmt *body_back() const {
1503    return !body_empty() ? body_begin()[size() - 1] : nullptr;
1504  }
1505
1506  using reverse_body_iterator = std::reverse_iterator<body_iterator>;
1507
1508  reverse_body_iterator body_rbegin() {
1509    return reverse_body_iterator(body_end());
1510  }
1511
1512  reverse_body_iterator body_rend() {
1513    return reverse_body_iterator(body_begin());
1514  }
1515
1516  using const_reverse_body_iterator =
1517      std::reverse_iterator<const_body_iterator>;
1518
1519  const_reverse_body_iterator body_rbegin() const {
1520    return const_reverse_body_iterator(body_end());
1521  }
1522
1523  const_reverse_body_iterator body_rend() const {
1524    return const_reverse_body_iterator(body_begin());
1525  }
1526
1527  // Get the Stmt that StmtExpr would consider to be the result of this
1528  // compound statement. This is used by StmtExpr to properly emulate the GCC
1529  // compound expression extension, which ignores trailing NullStmts when
1530  // getting the result of the expression.
1531  // i.e. ({ 5;;; })
1532  //           ^^ ignored
1533  // If we don't find something that isn't a NullStmt, just return the last
1534  // Stmt.
1535  Stmt *getStmtExprResult() {
1536    for (auto *B : llvm::reverse(body())) {
1537      if (!isa<NullStmt>(B))
1538        return B;
1539    }
1540    return body_back();
1541  }
1542
1543  const Stmt *getStmtExprResult() const {
1544    return const_cast<CompoundStmt *>(this)->getStmtExprResult();
1545  }
1546
1547  SourceLocation getBeginLoc() const { return LBraceLoc; }
1548  SourceLocation getEndLoc() const { return RBraceLoc; }
1549
1550  SourceLocation getLBracLoc() const { return LBraceLoc; }
1551  SourceLocation getRBracLoc() const { return RBraceLoc; }
1552
1553  static bool classof(const Stmt *T) {
1554    return T->getStmtClass() == CompoundStmtClass;
1555  }
1556
1557  // Iterators
1558  child_range children() { return child_range(body_begin(), body_end()); }
1559
1560  const_child_range children() const {
1561    return const_child_range(body_begin(), body_end());
1562  }
1563};
1564
1565// SwitchCase is the base class for CaseStmt and DefaultStmt,
1566class SwitchCase : public Stmt {
1567protected:
1568  /// The location of the ":".
1569  SourceLocation ColonLoc;
1570
1571  // The location of the "case" or "default" keyword. Stored in SwitchCaseBits.
1572  // SourceLocation KeywordLoc;
1573
1574  /// A pointer to the following CaseStmt or DefaultStmt class,
1575  /// used by SwitchStmt.
1576  SwitchCase *NextSwitchCase = nullptr;
1577
1578  SwitchCase(StmtClass SC, SourceLocation KWLoc, SourceLocation ColonLoc)
1579      : Stmt(SC), ColonLoc(ColonLoc) {
1580    setKeywordLoc(KWLoc);
1581  }
1582
1583  SwitchCase(StmtClass SC, EmptyShell) : Stmt(SC) {}
1584
1585public:
1586  const SwitchCase *getNextSwitchCase() const { return NextSwitchCase; }
1587  SwitchCase *getNextSwitchCase() { return NextSwitchCase; }
1588  void setNextSwitchCase(SwitchCase *SC) { NextSwitchCase = SC; }
1589
1590  SourceLocation getKeywordLoc() const { return SwitchCaseBits.KeywordLoc; }
1591  void setKeywordLoc(SourceLocation L) { SwitchCaseBits.KeywordLoc = L; }
1592  SourceLocation getColonLoc() const { return ColonLoc; }
1593  void setColonLoc(SourceLocation L) { ColonLoc = L; }
1594
1595  inline Stmt *getSubStmt();
1596  const Stmt *getSubStmt() const {
1597    return const_cast<SwitchCase *>(this)->getSubStmt();
1598  }
1599
1600  SourceLocation getBeginLoc() const { return getKeywordLoc(); }
1601  inline SourceLocation getEndLoc() const LLVM_READONLY;
1602
1603  static bool classof(const Stmt *T) {
1604    return T->getStmtClass() == CaseStmtClass ||
1605           T->getStmtClass() == DefaultStmtClass;
1606  }
1607};
1608
1609/// CaseStmt - Represent a case statement. It can optionally be a GNU case
1610/// statement of the form LHS ... RHS representing a range of cases.
1611class CaseStmt final
1612    : public SwitchCase,
1613      private llvm::TrailingObjects<CaseStmt, Stmt *, SourceLocation> {
1614  friend TrailingObjects;
1615
1616  // CaseStmt is followed by several trailing objects, some of which optional.
1617  // Note that it would be more convenient to put the optional trailing objects
1618  // at the end but this would impact children().
1619  // The trailing objects are in order:
1620  //
1621  // * A "Stmt *" for the LHS of the case statement. Always present.
1622  //
1623  // * A "Stmt *" for the RHS of the case statement. This is a GNU extension
1624  //   which allow ranges in cases statement of the form LHS ... RHS.
1625  //   Present if and only if caseStmtIsGNURange() is true.
1626  //
1627  // * A "Stmt *" for the substatement of the case statement. Always present.
1628  //
1629  // * A SourceLocation for the location of the ... if this is a case statement
1630  //   with a range. Present if and only if caseStmtIsGNURange() is true.
1631  enum { LhsOffset = 0, SubStmtOffsetFromRhs = 1 };
1632  enum { NumMandatoryStmtPtr = 2 };
1633
1634  unsigned numTrailingObjects(OverloadToken<Stmt *>) const {
1635    return NumMandatoryStmtPtr + caseStmtIsGNURange();
1636  }
1637
1638  unsigned numTrailingObjects(OverloadToken<SourceLocation>) const {
1639    return caseStmtIsGNURange();
1640  }
1641
1642  unsigned lhsOffset() const { return LhsOffset; }
1643  unsigned rhsOffset() const { return LhsOffset + caseStmtIsGNURange(); }
1644  unsigned subStmtOffset() const { return rhsOffset() + SubStmtOffsetFromRhs; }
1645
1646  /// Build a case statement assuming that the storage for the
1647  /// trailing objects has been properly allocated.
1648  CaseStmt(Expr *lhs, Expr *rhs, SourceLocation caseLoc,
1649           SourceLocation ellipsisLoc, SourceLocation colonLoc)
1650      : SwitchCase(CaseStmtClass, caseLoc, colonLoc) {
1651    // Handle GNU case statements of the form LHS ... RHS.
1652    bool IsGNURange = rhs != nullptr;
1653    SwitchCaseBits.CaseStmtIsGNURange = IsGNURange;
1654    setLHS(lhs);
1655    setSubStmt(nullptr);
1656    if (IsGNURange) {
1657      setRHS(rhs);
1658      setEllipsisLoc(ellipsisLoc);
1659    }
1660  }
1661
1662  /// Build an empty switch case statement.
1663  explicit CaseStmt(EmptyShell Empty, bool CaseStmtIsGNURange)
1664      : SwitchCase(CaseStmtClass, Empty) {
1665    SwitchCaseBits.CaseStmtIsGNURange = CaseStmtIsGNURange;
1666  }
1667
1668public:
1669  /// Build a case statement.
1670  static CaseStmt *Create(const ASTContext &Ctx, Expr *lhs, Expr *rhs,
1671                          SourceLocation caseLoc, SourceLocation ellipsisLoc,
1672                          SourceLocation colonLoc);
1673
1674  /// Build an empty case statement.
1675  static CaseStmt *CreateEmpty(const ASTContext &Ctx, bool CaseStmtIsGNURange);
1676
1677  /// True if this case statement is of the form case LHS ... RHS, which
1678  /// is a GNU extension. In this case the RHS can be obtained with getRHS()
1679  /// and the location of the ellipsis can be obtained with getEllipsisLoc().
1680  bool caseStmtIsGNURange() const { return SwitchCaseBits.CaseStmtIsGNURange; }
1681
1682  SourceLocation getCaseLoc() const { return getKeywordLoc(); }
1683  void setCaseLoc(SourceLocation L) { setKeywordLoc(L); }
1684
1685  /// Get the location of the ... in a case statement of the form LHS ... RHS.
1686  SourceLocation getEllipsisLoc() const {
1687    return caseStmtIsGNURange() ? *getTrailingObjects<SourceLocation>()
1688                                : SourceLocation();
1689  }
1690
1691  /// Set the location of the ... in a case statement of the form LHS ... RHS.
1692  /// Assert that this case statement is of this form.
1693  void setEllipsisLoc(SourceLocation L) {
1694    assert(
1695        caseStmtIsGNURange() &&
1696        "setEllipsisLoc but this is not a case stmt of the form LHS ... RHS!");
1697    *getTrailingObjects<SourceLocation>() = L;
1698  }
1699
1700  Expr *getLHS() {
1701    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[lhsOffset()]);
1702  }
1703
1704  const Expr *getLHS() const {
1705    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[lhsOffset()]);
1706  }
1707
1708  void setLHS(Expr *Val) {
1709    getTrailingObjects<Stmt *>()[lhsOffset()] = reinterpret_cast<Stmt *>(Val);
1710  }
1711
1712  Expr *getRHS() {
1713    return caseStmtIsGNURange() ? reinterpret_cast<Expr *>(
1714                                      getTrailingObjects<Stmt *>()[rhsOffset()])
1715                                : nullptr;
1716  }
1717
1718  const Expr *getRHS() const {
1719    return caseStmtIsGNURange() ? reinterpret_cast<Expr *>(
1720                                      getTrailingObjects<Stmt *>()[rhsOffset()])
1721                                : nullptr;
1722  }
1723
1724  void setRHS(Expr *Val) {
1725    assert(caseStmtIsGNURange() &&
1726           "setRHS but this is not a case stmt of the form LHS ... RHS!");
1727    getTrailingObjects<Stmt *>()[rhsOffset()] = reinterpret_cast<Stmt *>(Val);
1728  }
1729
1730  Stmt *getSubStmt() { return getTrailingObjects<Stmt *>()[subStmtOffset()]; }
1731  const Stmt *getSubStmt() const {
1732    return getTrailingObjects<Stmt *>()[subStmtOffset()];
1733  }
1734
1735  void setSubStmt(Stmt *S) {
1736    getTrailingObjects<Stmt *>()[subStmtOffset()] = S;
1737  }
1738
1739  SourceLocation getBeginLoc() const { return getKeywordLoc(); }
1740  SourceLocation getEndLoc() const LLVM_READONLY {
1741    // Handle deeply nested case statements with iteration instead of recursion.
1742    const CaseStmt *CS = this;
1743    while (const auto *CS2 = dyn_cast<CaseStmt>(CS->getSubStmt()))
1744      CS = CS2;
1745
1746    return CS->getSubStmt()->getEndLoc();
1747  }
1748
1749  static bool classof(const Stmt *T) {
1750    return T->getStmtClass() == CaseStmtClass;
1751  }
1752
1753  // Iterators
1754  child_range children() {
1755    return child_range(getTrailingObjects<Stmt *>(),
1756                       getTrailingObjects<Stmt *>() +
1757                           numTrailingObjects(OverloadToken<Stmt *>()));
1758  }
1759
1760  const_child_range children() const {
1761    return const_child_range(getTrailingObjects<Stmt *>(),
1762                             getTrailingObjects<Stmt *>() +
1763                                 numTrailingObjects(OverloadToken<Stmt *>()));
1764  }
1765};
1766
1767class DefaultStmt : public SwitchCase {
1768  Stmt *SubStmt;
1769
1770public:
1771  DefaultStmt(SourceLocation DL, SourceLocation CL, Stmt *substmt)
1772      : SwitchCase(DefaultStmtClass, DL, CL), SubStmt(substmt) {}
1773
1774  /// Build an empty default statement.
1775  explicit DefaultStmt(EmptyShell Empty)
1776      : SwitchCase(DefaultStmtClass, Empty) {}
1777
1778  Stmt *getSubStmt() { return SubStmt; }
1779  const Stmt *getSubStmt() const { return SubStmt; }
1780  void setSubStmt(Stmt *S) { SubStmt = S; }
1781
1782  SourceLocation getDefaultLoc() const { return getKeywordLoc(); }
1783  void setDefaultLoc(SourceLocation L) { setKeywordLoc(L); }
1784
1785  SourceLocation getBeginLoc() const { return getKeywordLoc(); }
1786  SourceLocation getEndLoc() const LLVM_READONLY {
1787    return SubStmt->getEndLoc();
1788  }
1789
1790  static bool classof(const Stmt *T) {
1791    return T->getStmtClass() == DefaultStmtClass;
1792  }
1793
1794  // Iterators
1795  child_range children() { return child_range(&SubStmt, &SubStmt + 1); }
1796
1797  const_child_range children() const {
1798    return const_child_range(&SubStmt, &SubStmt + 1);
1799  }
1800};
1801
1802SourceLocation SwitchCase::getEndLoc() const {
1803  if (const auto *CS = dyn_cast<CaseStmt>(this))
1804    return CS->getEndLoc();
1805  else if (const auto *DS = dyn_cast<DefaultStmt>(this))
1806    return DS->getEndLoc();
1807  llvm_unreachable("SwitchCase is neither a CaseStmt nor a DefaultStmt!");
1808}
1809
1810Stmt *SwitchCase::getSubStmt() {
1811  if (auto *CS = dyn_cast<CaseStmt>(this))
1812    return CS->getSubStmt();
1813  else if (auto *DS = dyn_cast<DefaultStmt>(this))
1814    return DS->getSubStmt();
1815  llvm_unreachable("SwitchCase is neither a CaseStmt nor a DefaultStmt!");
1816}
1817
1818/// Represents a statement that could possibly have a value and type. This
1819/// covers expression-statements, as well as labels and attributed statements.
1820///
1821/// Value statements have a special meaning when they are the last non-null
1822/// statement in a GNU statement expression, where they determine the value
1823/// of the statement expression.
1824class ValueStmt : public Stmt {
1825protected:
1826  using Stmt::Stmt;
1827
1828public:
1829  const Expr *getExprStmt() const;
1830  Expr *getExprStmt() {
1831    const ValueStmt *ConstThis = this;
1832    return const_cast<Expr*>(ConstThis->getExprStmt());
1833  }
1834
1835  static bool classof(const Stmt *T) {
1836    return T->getStmtClass() >= firstValueStmtConstant &&
1837           T->getStmtClass() <= lastValueStmtConstant;
1838  }
1839};
1840
1841/// LabelStmt - Represents a label, which has a substatement.  For example:
1842///    foo: return;
1843class LabelStmt : public ValueStmt {
1844  LabelDecl *TheDecl;
1845  Stmt *SubStmt;
1846  bool SideEntry = false;
1847
1848public:
1849  /// Build a label statement.
1850  LabelStmt(SourceLocation IL, LabelDecl *D, Stmt *substmt)
1851      : ValueStmt(LabelStmtClass), TheDecl(D), SubStmt(substmt) {
1852    setIdentLoc(IL);
1853  }
1854
1855  /// Build an empty label statement.
1856  explicit LabelStmt(EmptyShell Empty) : ValueStmt(LabelStmtClass, Empty) {}
1857
1858  SourceLocation getIdentLoc() const { return LabelStmtBits.IdentLoc; }
1859  void setIdentLoc(SourceLocation L) { LabelStmtBits.IdentLoc = L; }
1860
1861  LabelDecl *getDecl() const { return TheDecl; }
1862  void setDecl(LabelDecl *D) { TheDecl = D; }
1863
1864  const char *getName() const;
1865  Stmt *getSubStmt() { return SubStmt; }
1866
1867  const Stmt *getSubStmt() const { return SubStmt; }
1868  void setSubStmt(Stmt *SS) { SubStmt = SS; }
1869
1870  SourceLocation getBeginLoc() const { return getIdentLoc(); }
1871  SourceLocation getEndLoc() const LLVM_READONLY { return SubStmt->getEndLoc();}
1872
1873  child_range children() { return child_range(&SubStmt, &SubStmt + 1); }
1874
1875  const_child_range children() const {
1876    return const_child_range(&SubStmt, &SubStmt + 1);
1877  }
1878
1879  static bool classof(const Stmt *T) {
1880    return T->getStmtClass() == LabelStmtClass;
1881  }
1882  bool isSideEntry() const { return SideEntry; }
1883  void setSideEntry(bool SE) { SideEntry = SE; }
1884};
1885
1886/// Represents an attribute applied to a statement.
1887///
1888/// Represents an attribute applied to a statement. For example:
1889///   [[omp::for(...)]] for (...) { ... }
1890class AttributedStmt final
1891    : public ValueStmt,
1892      private llvm::TrailingObjects<AttributedStmt, const Attr *> {
1893  friend class ASTStmtReader;
1894  friend TrailingObjects;
1895
1896  Stmt *SubStmt;
1897
1898  AttributedStmt(SourceLocation Loc, ArrayRef<const Attr *> Attrs,
1899                 Stmt *SubStmt)
1900      : ValueStmt(AttributedStmtClass), SubStmt(SubStmt) {
1901    AttributedStmtBits.NumAttrs = Attrs.size();
1902    AttributedStmtBits.AttrLoc = Loc;
1903    std::copy(Attrs.begin(), Attrs.end(), getAttrArrayPtr());
1904  }
1905
1906  explicit AttributedStmt(EmptyShell Empty, unsigned NumAttrs)
1907      : ValueStmt(AttributedStmtClass, Empty) {
1908    AttributedStmtBits.NumAttrs = NumAttrs;
1909    AttributedStmtBits.AttrLoc = SourceLocation{};
1910    std::fill_n(getAttrArrayPtr(), NumAttrs, nullptr);
1911  }
1912
1913  const Attr *const *getAttrArrayPtr() const {
1914    return getTrailingObjects<const Attr *>();
1915  }
1916  const Attr **getAttrArrayPtr() { return getTrailingObjects<const Attr *>(); }
1917
1918public:
1919  static AttributedStmt *Create(const ASTContext &C, SourceLocation Loc,
1920                                ArrayRef<const Attr *> Attrs, Stmt *SubStmt);
1921
1922  // Build an empty attributed statement.
1923  static AttributedStmt *CreateEmpty(const ASTContext &C, unsigned NumAttrs);
1924
1925  SourceLocation getAttrLoc() const { return AttributedStmtBits.AttrLoc; }
1926  ArrayRef<const Attr *> getAttrs() const {
1927    return llvm::ArrayRef(getAttrArrayPtr(), AttributedStmtBits.NumAttrs);
1928  }
1929
1930  Stmt *getSubStmt() { return SubStmt; }
1931  const Stmt *getSubStmt() const { return SubStmt; }
1932
1933  SourceLocation getBeginLoc() const { return getAttrLoc(); }
1934  SourceLocation getEndLoc() const LLVM_READONLY { return SubStmt->getEndLoc();}
1935
1936  child_range children() { return child_range(&SubStmt, &SubStmt + 1); }
1937
1938  const_child_range children() const {
1939    return const_child_range(&SubStmt, &SubStmt + 1);
1940  }
1941
1942  static bool classof(const Stmt *T) {
1943    return T->getStmtClass() == AttributedStmtClass;
1944  }
1945};
1946
1947/// IfStmt - This represents an if/then/else.
1948class IfStmt final
1949    : public Stmt,
1950      private llvm::TrailingObjects<IfStmt, Stmt *, SourceLocation> {
1951  friend TrailingObjects;
1952
1953  // IfStmt is followed by several trailing objects, some of which optional.
1954  // Note that it would be more convenient to put the optional trailing
1955  // objects at then end but this would change the order of the children.
1956  // The trailing objects are in order:
1957  //
1958  // * A "Stmt *" for the init statement.
1959  //    Present if and only if hasInitStorage().
1960  //
1961  // * A "Stmt *" for the condition variable.
1962  //    Present if and only if hasVarStorage(). This is in fact a "DeclStmt *".
1963  //
1964  // * A "Stmt *" for the condition.
1965  //    Always present. This is in fact a "Expr *".
1966  //
1967  // * A "Stmt *" for the then statement.
1968  //    Always present.
1969  //
1970  // * A "Stmt *" for the else statement.
1971  //    Present if and only if hasElseStorage().
1972  //
1973  // * A "SourceLocation" for the location of the "else".
1974  //    Present if and only if hasElseStorage().
1975  enum { InitOffset = 0, ThenOffsetFromCond = 1, ElseOffsetFromCond = 2 };
1976  enum { NumMandatoryStmtPtr = 2 };
1977  SourceLocation LParenLoc;
1978  SourceLocation RParenLoc;
1979
1980  unsigned numTrailingObjects(OverloadToken<Stmt *>) const {
1981    return NumMandatoryStmtPtr + hasElseStorage() + hasVarStorage() +
1982           hasInitStorage();
1983  }
1984
1985  unsigned numTrailingObjects(OverloadToken<SourceLocation>) const {
1986    return hasElseStorage();
1987  }
1988
1989  unsigned initOffset() const { return InitOffset; }
1990  unsigned varOffset() const { return InitOffset + hasInitStorage(); }
1991  unsigned condOffset() const {
1992    return InitOffset + hasInitStorage() + hasVarStorage();
1993  }
1994  unsigned thenOffset() const { return condOffset() + ThenOffsetFromCond; }
1995  unsigned elseOffset() const { return condOffset() + ElseOffsetFromCond; }
1996
1997  /// Build an if/then/else statement.
1998  IfStmt(const ASTContext &Ctx, SourceLocation IL, IfStatementKind Kind,
1999         Stmt *Init, VarDecl *Var, Expr *Cond, SourceLocation LParenLoc,
2000         SourceLocation RParenLoc, Stmt *Then, SourceLocation EL, Stmt *Else);
2001
2002  /// Build an empty if/then/else statement.
2003  explicit IfStmt(EmptyShell Empty, bool HasElse, bool HasVar, bool HasInit);
2004
2005public:
2006  /// Create an IfStmt.
2007  static IfStmt *Create(const ASTContext &Ctx, SourceLocation IL,
2008                        IfStatementKind Kind, Stmt *Init, VarDecl *Var,
2009                        Expr *Cond, SourceLocation LPL, SourceLocation RPL,
2010                        Stmt *Then, SourceLocation EL = SourceLocation(),
2011                        Stmt *Else = nullptr);
2012
2013  /// Create an empty IfStmt optionally with storage for an else statement,
2014  /// condition variable and init expression.
2015  static IfStmt *CreateEmpty(const ASTContext &Ctx, bool HasElse, bool HasVar,
2016                             bool HasInit);
2017
2018  /// True if this IfStmt has the storage for an init statement.
2019  bool hasInitStorage() const { return IfStmtBits.HasInit; }
2020
2021  /// True if this IfStmt has storage for a variable declaration.
2022  bool hasVarStorage() const { return IfStmtBits.HasVar; }
2023
2024  /// True if this IfStmt has storage for an else statement.
2025  bool hasElseStorage() const { return IfStmtBits.HasElse; }
2026
2027  Expr *getCond() {
2028    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[condOffset()]);
2029  }
2030
2031  const Expr *getCond() const {
2032    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[condOffset()]);
2033  }
2034
2035  void setCond(Expr *Cond) {
2036    getTrailingObjects<Stmt *>()[condOffset()] = reinterpret_cast<Stmt *>(Cond);
2037  }
2038
2039  Stmt *getThen() { return getTrailingObjects<Stmt *>()[thenOffset()]; }
2040  const Stmt *getThen() const {
2041    return getTrailingObjects<Stmt *>()[thenOffset()];
2042  }
2043
2044  void setThen(Stmt *Then) {
2045    getTrailingObjects<Stmt *>()[thenOffset()] = Then;
2046  }
2047
2048  Stmt *getElse() {
2049    return hasElseStorage() ? getTrailingObjects<Stmt *>()[elseOffset()]
2050                            : nullptr;
2051  }
2052
2053  const Stmt *getElse() const {
2054    return hasElseStorage() ? getTrailingObjects<Stmt *>()[elseOffset()]
2055                            : nullptr;
2056  }
2057
2058  void setElse(Stmt *Else) {
2059    assert(hasElseStorage() &&
2060           "This if statement has no storage for an else statement!");
2061    getTrailingObjects<Stmt *>()[elseOffset()] = Else;
2062  }
2063
2064  /// Retrieve the variable declared in this "if" statement, if any.
2065  ///
2066  /// In the following example, "x" is the condition variable.
2067  /// \code
2068  /// if (int x = foo()) {
2069  ///   printf("x is %d", x);
2070  /// }
2071  /// \endcode
2072  VarDecl *getConditionVariable();
2073  const VarDecl *getConditionVariable() const {
2074    return const_cast<IfStmt *>(this)->getConditionVariable();
2075  }
2076
2077  /// Set the condition variable for this if statement.
2078  /// The if statement must have storage for the condition variable.
2079  void setConditionVariable(const ASTContext &Ctx, VarDecl *V);
2080
2081  /// If this IfStmt has a condition variable, return the faux DeclStmt
2082  /// associated with the creation of that condition variable.
2083  DeclStmt *getConditionVariableDeclStmt() {
2084    return hasVarStorage() ? static_cast<DeclStmt *>(
2085                                 getTrailingObjects<Stmt *>()[varOffset()])
2086                           : nullptr;
2087  }
2088
2089  const DeclStmt *getConditionVariableDeclStmt() const {
2090    return hasVarStorage() ? static_cast<DeclStmt *>(
2091                                 getTrailingObjects<Stmt *>()[varOffset()])
2092                           : nullptr;
2093  }
2094
2095  Stmt *getInit() {
2096    return hasInitStorage() ? getTrailingObjects<Stmt *>()[initOffset()]
2097                            : nullptr;
2098  }
2099
2100  const Stmt *getInit() const {
2101    return hasInitStorage() ? getTrailingObjects<Stmt *>()[initOffset()]
2102                            : nullptr;
2103  }
2104
2105  void setInit(Stmt *Init) {
2106    assert(hasInitStorage() &&
2107           "This if statement has no storage for an init statement!");
2108    getTrailingObjects<Stmt *>()[initOffset()] = Init;
2109  }
2110
2111  SourceLocation getIfLoc() const { return IfStmtBits.IfLoc; }
2112  void setIfLoc(SourceLocation IfLoc) { IfStmtBits.IfLoc = IfLoc; }
2113
2114  SourceLocation getElseLoc() const {
2115    return hasElseStorage() ? *getTrailingObjects<SourceLocation>()
2116                            : SourceLocation();
2117  }
2118
2119  void setElseLoc(SourceLocation ElseLoc) {
2120    assert(hasElseStorage() &&
2121           "This if statement has no storage for an else statement!");
2122    *getTrailingObjects<SourceLocation>() = ElseLoc;
2123  }
2124
2125  bool isConsteval() const {
2126    return getStatementKind() == IfStatementKind::ConstevalNonNegated ||
2127           getStatementKind() == IfStatementKind::ConstevalNegated;
2128  }
2129
2130  bool isNonNegatedConsteval() const {
2131    return getStatementKind() == IfStatementKind::ConstevalNonNegated;
2132  }
2133
2134  bool isNegatedConsteval() const {
2135    return getStatementKind() == IfStatementKind::ConstevalNegated;
2136  }
2137
2138  bool isConstexpr() const {
2139    return getStatementKind() == IfStatementKind::Constexpr;
2140  }
2141
2142  void setStatementKind(IfStatementKind Kind) {
2143    IfStmtBits.Kind = static_cast<unsigned>(Kind);
2144  }
2145
2146  IfStatementKind getStatementKind() const {
2147    return static_cast<IfStatementKind>(IfStmtBits.Kind);
2148  }
2149
2150  /// If this is an 'if constexpr', determine which substatement will be taken.
2151  /// Otherwise, or if the condition is value-dependent, returns std::nullopt.
2152  std::optional<const Stmt *> getNondiscardedCase(const ASTContext &Ctx) const;
2153  std::optional<Stmt *> getNondiscardedCase(const ASTContext &Ctx);
2154
2155  bool isObjCAvailabilityCheck() const;
2156
2157  SourceLocation getBeginLoc() const { return getIfLoc(); }
2158  SourceLocation getEndLoc() const LLVM_READONLY {
2159    if (getElse())
2160      return getElse()->getEndLoc();
2161    return getThen()->getEndLoc();
2162  }
2163  SourceLocation getLParenLoc() const { return LParenLoc; }
2164  void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
2165  SourceLocation getRParenLoc() const { return RParenLoc; }
2166  void setRParenLoc(SourceLocation Loc) { RParenLoc = Loc; }
2167
2168  // Iterators over subexpressions.  The iterators will include iterating
2169  // over the initialization expression referenced by the condition variable.
2170  child_range children() {
2171    // We always store a condition, but there is none for consteval if
2172    // statements, so skip it.
2173    return child_range(getTrailingObjects<Stmt *>() +
2174                           (isConsteval() ? thenOffset() : 0),
2175                       getTrailingObjects<Stmt *>() +
2176                           numTrailingObjects(OverloadToken<Stmt *>()));
2177  }
2178
2179  const_child_range children() const {
2180    // We always store a condition, but there is none for consteval if
2181    // statements, so skip it.
2182    return const_child_range(getTrailingObjects<Stmt *>() +
2183                                 (isConsteval() ? thenOffset() : 0),
2184                             getTrailingObjects<Stmt *>() +
2185                                 numTrailingObjects(OverloadToken<Stmt *>()));
2186  }
2187
2188  static bool classof(const Stmt *T) {
2189    return T->getStmtClass() == IfStmtClass;
2190  }
2191};
2192
2193/// SwitchStmt - This represents a 'switch' stmt.
2194class SwitchStmt final : public Stmt,
2195                         private llvm::TrailingObjects<SwitchStmt, Stmt *> {
2196  friend TrailingObjects;
2197
2198  /// Points to a linked list of case and default statements.
2199  SwitchCase *FirstCase = nullptr;
2200
2201  // SwitchStmt is followed by several trailing objects,
2202  // some of which optional. Note that it would be more convenient to
2203  // put the optional trailing objects at the end but this would change
2204  // the order in children().
2205  // The trailing objects are in order:
2206  //
2207  // * A "Stmt *" for the init statement.
2208  //    Present if and only if hasInitStorage().
2209  //
2210  // * A "Stmt *" for the condition variable.
2211  //    Present if and only if hasVarStorage(). This is in fact a "DeclStmt *".
2212  //
2213  // * A "Stmt *" for the condition.
2214  //    Always present. This is in fact an "Expr *".
2215  //
2216  // * A "Stmt *" for the body.
2217  //    Always present.
2218  enum { InitOffset = 0, BodyOffsetFromCond = 1 };
2219  enum { NumMandatoryStmtPtr = 2 };
2220  SourceLocation LParenLoc;
2221  SourceLocation RParenLoc;
2222
2223  unsigned numTrailingObjects(OverloadToken<Stmt *>) const {
2224    return NumMandatoryStmtPtr + hasInitStorage() + hasVarStorage();
2225  }
2226
2227  unsigned initOffset() const { return InitOffset; }
2228  unsigned varOffset() const { return InitOffset + hasInitStorage(); }
2229  unsigned condOffset() const {
2230    return InitOffset + hasInitStorage() + hasVarStorage();
2231  }
2232  unsigned bodyOffset() const { return condOffset() + BodyOffsetFromCond; }
2233
2234  /// Build a switch statement.
2235  SwitchStmt(const ASTContext &Ctx, Stmt *Init, VarDecl *Var, Expr *Cond,
2236             SourceLocation LParenLoc, SourceLocation RParenLoc);
2237
2238  /// Build a empty switch statement.
2239  explicit SwitchStmt(EmptyShell Empty, bool HasInit, bool HasVar);
2240
2241public:
2242  /// Create a switch statement.
2243  static SwitchStmt *Create(const ASTContext &Ctx, Stmt *Init, VarDecl *Var,
2244                            Expr *Cond, SourceLocation LParenLoc,
2245                            SourceLocation RParenLoc);
2246
2247  /// Create an empty switch statement optionally with storage for
2248  /// an init expression and a condition variable.
2249  static SwitchStmt *CreateEmpty(const ASTContext &Ctx, bool HasInit,
2250                                 bool HasVar);
2251
2252  /// True if this SwitchStmt has storage for an init statement.
2253  bool hasInitStorage() const { return SwitchStmtBits.HasInit; }
2254
2255  /// True if this SwitchStmt has storage for a condition variable.
2256  bool hasVarStorage() const { return SwitchStmtBits.HasVar; }
2257
2258  Expr *getCond() {
2259    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[condOffset()]);
2260  }
2261
2262  const Expr *getCond() const {
2263    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[condOffset()]);
2264  }
2265
2266  void setCond(Expr *Cond) {
2267    getTrailingObjects<Stmt *>()[condOffset()] = reinterpret_cast<Stmt *>(Cond);
2268  }
2269
2270  Stmt *getBody() { return getTrailingObjects<Stmt *>()[bodyOffset()]; }
2271  const Stmt *getBody() const {
2272    return getTrailingObjects<Stmt *>()[bodyOffset()];
2273  }
2274
2275  void setBody(Stmt *Body) {
2276    getTrailingObjects<Stmt *>()[bodyOffset()] = Body;
2277  }
2278
2279  Stmt *getInit() {
2280    return hasInitStorage() ? getTrailingObjects<Stmt *>()[initOffset()]
2281                            : nullptr;
2282  }
2283
2284  const Stmt *getInit() const {
2285    return hasInitStorage() ? getTrailingObjects<Stmt *>()[initOffset()]
2286                            : nullptr;
2287  }
2288
2289  void setInit(Stmt *Init) {
2290    assert(hasInitStorage() &&
2291           "This switch statement has no storage for an init statement!");
2292    getTrailingObjects<Stmt *>()[initOffset()] = Init;
2293  }
2294
2295  /// Retrieve the variable declared in this "switch" statement, if any.
2296  ///
2297  /// In the following example, "x" is the condition variable.
2298  /// \code
2299  /// switch (int x = foo()) {
2300  ///   case 0: break;
2301  ///   // ...
2302  /// }
2303  /// \endcode
2304  VarDecl *getConditionVariable();
2305  const VarDecl *getConditionVariable() const {
2306    return const_cast<SwitchStmt *>(this)->getConditionVariable();
2307  }
2308
2309  /// Set the condition variable in this switch statement.
2310  /// The switch statement must have storage for it.
2311  void setConditionVariable(const ASTContext &Ctx, VarDecl *VD);
2312
2313  /// If this SwitchStmt has a condition variable, return the faux DeclStmt
2314  /// associated with the creation of that condition variable.
2315  DeclStmt *getConditionVariableDeclStmt() {
2316    return hasVarStorage() ? static_cast<DeclStmt *>(
2317                                 getTrailingObjects<Stmt *>()[varOffset()])
2318                           : nullptr;
2319  }
2320
2321  const DeclStmt *getConditionVariableDeclStmt() const {
2322    return hasVarStorage() ? static_cast<DeclStmt *>(
2323                                 getTrailingObjects<Stmt *>()[varOffset()])
2324                           : nullptr;
2325  }
2326
2327  SwitchCase *getSwitchCaseList() { return FirstCase; }
2328  const SwitchCase *getSwitchCaseList() const { return FirstCase; }
2329  void setSwitchCaseList(SwitchCase *SC) { FirstCase = SC; }
2330
2331  SourceLocation getSwitchLoc() const { return SwitchStmtBits.SwitchLoc; }
2332  void setSwitchLoc(SourceLocation L) { SwitchStmtBits.SwitchLoc = L; }
2333  SourceLocation getLParenLoc() const { return LParenLoc; }
2334  void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
2335  SourceLocation getRParenLoc() const { return RParenLoc; }
2336  void setRParenLoc(SourceLocation Loc) { RParenLoc = Loc; }
2337
2338  void setBody(Stmt *S, SourceLocation SL) {
2339    setBody(S);
2340    setSwitchLoc(SL);
2341  }
2342
2343  void addSwitchCase(SwitchCase *SC) {
2344    assert(!SC->getNextSwitchCase() &&
2345           "case/default already added to a switch");
2346    SC->setNextSwitchCase(FirstCase);
2347    FirstCase = SC;
2348  }
2349
2350  /// Set a flag in the SwitchStmt indicating that if the 'switch (X)' is a
2351  /// switch over an enum value then all cases have been explicitly covered.
2352  void setAllEnumCasesCovered() { SwitchStmtBits.AllEnumCasesCovered = true; }
2353
2354  /// Returns true if the SwitchStmt is a switch of an enum value and all cases
2355  /// have been explicitly covered.
2356  bool isAllEnumCasesCovered() const {
2357    return SwitchStmtBits.AllEnumCasesCovered;
2358  }
2359
2360  SourceLocation getBeginLoc() const { return getSwitchLoc(); }
2361  SourceLocation getEndLoc() const LLVM_READONLY {
2362    return getBody() ? getBody()->getEndLoc()
2363                     : reinterpret_cast<const Stmt *>(getCond())->getEndLoc();
2364  }
2365
2366  // Iterators
2367  child_range children() {
2368    return child_range(getTrailingObjects<Stmt *>(),
2369                       getTrailingObjects<Stmt *>() +
2370                           numTrailingObjects(OverloadToken<Stmt *>()));
2371  }
2372
2373  const_child_range children() const {
2374    return const_child_range(getTrailingObjects<Stmt *>(),
2375                             getTrailingObjects<Stmt *>() +
2376                                 numTrailingObjects(OverloadToken<Stmt *>()));
2377  }
2378
2379  static bool classof(const Stmt *T) {
2380    return T->getStmtClass() == SwitchStmtClass;
2381  }
2382};
2383
2384/// WhileStmt - This represents a 'while' stmt.
2385class WhileStmt final : public Stmt,
2386                        private llvm::TrailingObjects<WhileStmt, Stmt *> {
2387  friend TrailingObjects;
2388
2389  // WhileStmt is followed by several trailing objects,
2390  // some of which optional. Note that it would be more
2391  // convenient to put the optional trailing object at the end
2392  // but this would affect children().
2393  // The trailing objects are in order:
2394  //
2395  // * A "Stmt *" for the condition variable.
2396  //    Present if and only if hasVarStorage(). This is in fact a "DeclStmt *".
2397  //
2398  // * A "Stmt *" for the condition.
2399  //    Always present. This is in fact an "Expr *".
2400  //
2401  // * A "Stmt *" for the body.
2402  //    Always present.
2403  //
2404  enum { VarOffset = 0, BodyOffsetFromCond = 1 };
2405  enum { NumMandatoryStmtPtr = 2 };
2406
2407  SourceLocation LParenLoc, RParenLoc;
2408
2409  unsigned varOffset() const { return VarOffset; }
2410  unsigned condOffset() const { return VarOffset + hasVarStorage(); }
2411  unsigned bodyOffset() const { return condOffset() + BodyOffsetFromCond; }
2412
2413  unsigned numTrailingObjects(OverloadToken<Stmt *>) const {
2414    return NumMandatoryStmtPtr + hasVarStorage();
2415  }
2416
2417  /// Build a while statement.
2418  WhileStmt(const ASTContext &Ctx, VarDecl *Var, Expr *Cond, Stmt *Body,
2419            SourceLocation WL, SourceLocation LParenLoc,
2420            SourceLocation RParenLoc);
2421
2422  /// Build an empty while statement.
2423  explicit WhileStmt(EmptyShell Empty, bool HasVar);
2424
2425public:
2426  /// Create a while statement.
2427  static WhileStmt *Create(const ASTContext &Ctx, VarDecl *Var, Expr *Cond,
2428                           Stmt *Body, SourceLocation WL,
2429                           SourceLocation LParenLoc, SourceLocation RParenLoc);
2430
2431  /// Create an empty while statement optionally with storage for
2432  /// a condition variable.
2433  static WhileStmt *CreateEmpty(const ASTContext &Ctx, bool HasVar);
2434
2435  /// True if this WhileStmt has storage for a condition variable.
2436  bool hasVarStorage() const { return WhileStmtBits.HasVar; }
2437
2438  Expr *getCond() {
2439    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[condOffset()]);
2440  }
2441
2442  const Expr *getCond() const {
2443    return reinterpret_cast<Expr *>(getTrailingObjects<Stmt *>()[condOffset()]);
2444  }
2445
2446  void setCond(Expr *Cond) {
2447    getTrailingObjects<Stmt *>()[condOffset()] = reinterpret_cast<Stmt *>(Cond);
2448  }
2449
2450  Stmt *getBody() { return getTrailingObjects<Stmt *>()[bodyOffset()]; }
2451  const Stmt *getBody() const {
2452    return getTrailingObjects<Stmt *>()[bodyOffset()];
2453  }
2454
2455  void setBody(Stmt *Body) {
2456    getTrailingObjects<Stmt *>()[bodyOffset()] = Body;
2457  }
2458
2459  /// Retrieve the variable declared in this "while" statement, if any.
2460  ///
2461  /// In the following example, "x" is the condition variable.
2462  /// \code
2463  /// while (int x = random()) {
2464  ///   // ...
2465  /// }
2466  /// \endcode
2467  VarDecl *getConditionVariable();
2468  const VarDecl *getConditionVariable() const {
2469    return const_cast<WhileStmt *>(this)->getConditionVariable();
2470  }
2471
2472  /// Set the condition variable of this while statement.
2473  /// The while statement must have storage for it.
2474  void setConditionVariable(const ASTContext &Ctx, VarDecl *V);
2475
2476  /// If this WhileStmt has a condition variable, return the faux DeclStmt
2477  /// associated with the creation of that condition variable.
2478  DeclStmt *getConditionVariableDeclStmt() {
2479    return hasVarStorage() ? static_cast<DeclStmt *>(
2480                                 getTrailingObjects<Stmt *>()[varOffset()])
2481                           : nullptr;
2482  }
2483
2484  const DeclStmt *getConditionVariableDeclStmt() const {
2485    return hasVarStorage() ? static_cast<DeclStmt *>(
2486                                 getTrailingObjects<Stmt *>()[varOffset()])
2487                           : nullptr;
2488  }
2489
2490  SourceLocation getWhileLoc() const { return WhileStmtBits.WhileLoc; }
2491  void setWhileLoc(SourceLocation L) { WhileStmtBits.WhileLoc = L; }
2492
2493  SourceLocation getLParenLoc() const { return LParenLoc; }
2494  void setLParenLoc(SourceLocation L) { LParenLoc = L; }
2495  SourceLocation getRParenLoc() const { return RParenLoc; }
2496  void setRParenLoc(SourceLocation L) { RParenLoc = L; }
2497
2498  SourceLocation getBeginLoc() const { return getWhileLoc(); }
2499  SourceLocation getEndLoc() const LLVM_READONLY {
2500    return getBody()->getEndLoc();
2501  }
2502
2503  static bool classof(const Stmt *T) {
2504    return T->getStmtClass() == WhileStmtClass;
2505  }
2506
2507  // Iterators
2508  child_range children() {
2509    return child_range(getTrailingObjects<Stmt *>(),
2510                       getTrailingObjects<Stmt *>() +
2511                           numTrailingObjects(OverloadToken<Stmt *>()));
2512  }
2513
2514  const_child_range children() const {
2515    return const_child_range(getTrailingObjects<Stmt *>(),
2516                             getTrailingObjects<Stmt *>() +
2517                                 numTrailingObjects(OverloadToken<Stmt *>()));
2518  }
2519};
2520
2521/// DoStmt - This represents a 'do/while' stmt.
2522class DoStmt : public Stmt {
2523  enum { BODY, COND, END_EXPR };
2524  Stmt *SubExprs[END_EXPR];
2525  SourceLocation WhileLoc;
2526  SourceLocation RParenLoc; // Location of final ')' in do stmt condition.
2527
2528public:
2529  DoStmt(Stmt *Body, Expr *Cond, SourceLocation DL, SourceLocation WL,
2530         SourceLocation RP)
2531      : Stmt(DoStmtClass), WhileLoc(WL), RParenLoc(RP) {
2532    setCond(Cond);
2533    setBody(Body);
2534    setDoLoc(DL);
2535  }
2536
2537  /// Build an empty do-while statement.
2538  explicit DoStmt(EmptyShell Empty) : Stmt(DoStmtClass, Empty) {}
2539
2540  Expr *getCond() { return reinterpret_cast<Expr *>(SubExprs[COND]); }
2541  const Expr *getCond() const {
2542    return reinterpret_cast<Expr *>(SubExprs[COND]);
2543  }
2544
2545  void setCond(Expr *Cond) { SubExprs[COND] = reinterpret_cast<Stmt *>(Cond); }
2546
2547  Stmt *getBody() { return SubExprs[BODY]; }
2548  const Stmt *getBody() const { return SubExprs[BODY]; }
2549  void setBody(Stmt *Body) { SubExprs[BODY] = Body; }
2550
2551  SourceLocation getDoLoc() const { return DoStmtBits.DoLoc; }
2552  void setDoLoc(SourceLocation L) { DoStmtBits.DoLoc = L; }
2553  SourceLocation getWhileLoc() const { return WhileLoc; }
2554  void setWhileLoc(SourceLocation L) { WhileLoc = L; }
2555  SourceLocation getRParenLoc() const { return RParenLoc; }
2556  void setRParenLoc(SourceLocation L) { RParenLoc = L; }
2557
2558  SourceLocation getBeginLoc() const { return getDoLoc(); }
2559  SourceLocation getEndLoc() const { return getRParenLoc(); }
2560
2561  static bool classof(const Stmt *T) {
2562    return T->getStmtClass() == DoStmtClass;
2563  }
2564
2565  // Iterators
2566  child_range children() {
2567    return child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
2568  }
2569
2570  const_child_range children() const {
2571    return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
2572  }
2573};
2574
2575/// ForStmt - This represents a 'for (init;cond;inc)' stmt.  Note that any of
2576/// the init/cond/inc parts of the ForStmt will be null if they were not
2577/// specified in the source.
2578class ForStmt : public Stmt {
2579  enum { INIT, CONDVAR, COND, INC, BODY, END_EXPR };
2580  Stmt* SubExprs[END_EXPR]; // SubExprs[INIT] is an expression or declstmt.
2581  SourceLocation LParenLoc, RParenLoc;
2582
2583public:
2584  ForStmt(const ASTContext &C, Stmt *Init, Expr *Cond, VarDecl *condVar,
2585          Expr *Inc, Stmt *Body, SourceLocation FL, SourceLocation LP,
2586          SourceLocation RP);
2587
2588  /// Build an empty for statement.
2589  explicit ForStmt(EmptyShell Empty) : Stmt(ForStmtClass, Empty) {}
2590
2591  Stmt *getInit() { return SubExprs[INIT]; }
2592
2593  /// Retrieve the variable declared in this "for" statement, if any.
2594  ///
2595  /// In the following example, "y" is the condition variable.
2596  /// \code
2597  /// for (int x = random(); int y = mangle(x); ++x) {
2598  ///   // ...
2599  /// }
2600  /// \endcode
2601  VarDecl *getConditionVariable() const;
2602  void setConditionVariable(const ASTContext &C, VarDecl *V);
2603
2604  /// If this ForStmt has a condition variable, return the faux DeclStmt
2605  /// associated with the creation of that condition variable.
2606  const DeclStmt *getConditionVariableDeclStmt() const {
2607    return reinterpret_cast<DeclStmt*>(SubExprs[CONDVAR]);
2608  }
2609
2610  Expr *getCond() { return reinterpret_cast<Expr*>(SubExprs[COND]); }
2611  Expr *getInc()  { return reinterpret_cast<Expr*>(SubExprs[INC]); }
2612  Stmt *getBody() { return SubExprs[BODY]; }
2613
2614  const Stmt *getInit() const { return SubExprs[INIT]; }
2615  const Expr *getCond() const { return reinterpret_cast<Expr*>(SubExprs[COND]);}
2616  const Expr *getInc()  const { return reinterpret_cast<Expr*>(SubExprs[INC]); }
2617  const Stmt *getBody() const { return SubExprs[BODY]; }
2618
2619  void setInit(Stmt *S) { SubExprs[INIT] = S; }
2620  void setCond(Expr *E) { SubExprs[COND] = reinterpret_cast<Stmt*>(E); }
2621  void setInc(Expr *E) { SubExprs[INC] = reinterpret_cast<Stmt*>(E); }
2622  void setBody(Stmt *S) { SubExprs[BODY] = S; }
2623
2624  SourceLocation getForLoc() const { return ForStmtBits.ForLoc; }
2625  void setForLoc(SourceLocation L) { ForStmtBits.ForLoc = L; }
2626  SourceLocation getLParenLoc() const { return LParenLoc; }
2627  void setLParenLoc(SourceLocation L) { LParenLoc = L; }
2628  SourceLocation getRParenLoc() const { return RParenLoc; }
2629  void setRParenLoc(SourceLocation L) { RParenLoc = L; }
2630
2631  SourceLocation getBeginLoc() const { return getForLoc(); }
2632  SourceLocation getEndLoc() const { return getBody()->getEndLoc(); }
2633
2634  static bool classof(const Stmt *T) {
2635    return T->getStmtClass() == ForStmtClass;
2636  }
2637
2638  // Iterators
2639  child_range children() {
2640    return child_range(&SubExprs[0], &SubExprs[0]+END_EXPR);
2641  }
2642
2643  const_child_range children() const {
2644    return const_child_range(&SubExprs[0], &SubExprs[0] + END_EXPR);
2645  }
2646};
2647
2648/// GotoStmt - This represents a direct goto.
2649class GotoStmt : public Stmt {
2650  LabelDecl *Label;
2651  SourceLocation LabelLoc;
2652
2653public:
2654  GotoStmt(LabelDecl *label, SourceLocation GL, SourceLocation LL)
2655      : Stmt(GotoStmtClass), Label(label), LabelLoc(LL) {
2656    setGotoLoc(GL);
2657  }
2658
2659  /// Build an empty goto statement.
2660  explicit GotoStmt(EmptyShell Empty) : Stmt(GotoStmtClass, Empty) {}
2661
2662  LabelDecl *getLabel() const { return Label; }
2663  void setLabel(LabelDecl *D) { Label = D; }
2664
2665  SourceLocation getGotoLoc() const { return GotoStmtBits.GotoLoc; }
2666  void setGotoLoc(SourceLocation L) { GotoStmtBits.GotoLoc = L; }
2667  SourceLocation getLabelLoc() const { return LabelLoc; }
2668  void setLabelLoc(SourceLocation L) { LabelLoc = L; }
2669
2670  SourceLocation getBeginLoc() const { return getGotoLoc(); }
2671  SourceLocation getEndLoc() const { return getLabelLoc(); }
2672
2673  static bool classof(const Stmt *T) {
2674    return T->getStmtClass() == GotoStmtClass;
2675  }
2676
2677  // Iterators
2678  child_range children() {
2679    return child_range(child_iterator(), child_iterator());
2680  }
2681
2682  const_child_range children() const {
2683    return const_child_range(const_child_iterator(), const_child_iterator());
2684  }
2685};
2686
2687/// IndirectGotoStmt - This represents an indirect goto.
2688class IndirectGotoStmt : public Stmt {
2689  SourceLocation StarLoc;
2690  Stmt *Target;
2691
2692public:
2693  IndirectGotoStmt(SourceLocation gotoLoc, SourceLocation starLoc, Expr *target)
2694      : Stmt(IndirectGotoStmtClass), StarLoc(starLoc) {
2695    setTarget(target);
2696    setGotoLoc(gotoLoc);
2697  }
2698
2699  /// Build an empty indirect goto statement.
2700  explicit IndirectGotoStmt(EmptyShell Empty)
2701      : Stmt(IndirectGotoStmtClass, Empty) {}
2702
2703  void setGotoLoc(SourceLocation L) { GotoStmtBits.GotoLoc = L; }
2704  SourceLocation getGotoLoc() const { return GotoStmtBits.GotoLoc; }
2705  void setStarLoc(SourceLocation L) { StarLoc = L; }
2706  SourceLocation getStarLoc() const { return StarLoc; }
2707
2708  Expr *getTarget() { return reinterpret_cast<Expr *>(Target); }
2709  const Expr *getTarget() const {
2710    return reinterpret_cast<const Expr *>(Target);
2711  }
2712  void setTarget(Expr *E) { Target = reinterpret_cast<Stmt *>(E); }
2713
2714  /// getConstantTarget - Returns the fixed target of this indirect
2715  /// goto, if one exists.
2716  LabelDecl *getConstantTarget();
2717  const LabelDecl *getConstantTarget() const {
2718    return const_cast<IndirectGotoStmt *>(this)->getConstantTarget();
2719  }
2720
2721  SourceLocation getBeginLoc() const { return getGotoLoc(); }
2722  SourceLocation getEndLoc() const LLVM_READONLY { return Target->getEndLoc(); }
2723
2724  static bool classof(const Stmt *T) {
2725    return T->getStmtClass() == IndirectGotoStmtClass;
2726  }
2727
2728  // Iterators
2729  child_range children() { return child_range(&Target, &Target + 1); }
2730
2731  const_child_range children() const {
2732    return const_child_range(&Target, &Target + 1);
2733  }
2734};
2735
2736/// ContinueStmt - This represents a continue.
2737class ContinueStmt : public Stmt {
2738public:
2739  ContinueStmt(SourceLocation CL) : Stmt(ContinueStmtClass) {
2740    setContinueLoc(CL);
2741  }
2742
2743  /// Build an empty continue statement.
2744  explicit ContinueStmt(EmptyShell Empty) : Stmt(ContinueStmtClass, Empty) {}
2745
2746  SourceLocation getContinueLoc() const { return ContinueStmtBits.ContinueLoc; }
2747  void setContinueLoc(SourceLocation L) { ContinueStmtBits.ContinueLoc = L; }
2748
2749  SourceLocation getBeginLoc() const { return getContinueLoc(); }
2750  SourceLocation getEndLoc() const { return getContinueLoc(); }
2751
2752  static bool classof(const Stmt *T) {
2753    return T->getStmtClass() == ContinueStmtClass;
2754  }
2755
2756  // Iterators
2757  child_range children() {
2758    return child_range(child_iterator(), child_iterator());
2759  }
2760
2761  const_child_range children() const {
2762    return const_child_range(const_child_iterator(), const_child_iterator());
2763  }
2764};
2765
2766/// BreakStmt - This represents a break.
2767class BreakStmt : public Stmt {
2768public:
2769  BreakStmt(SourceLocation BL) : Stmt(BreakStmtClass) {
2770    setBreakLoc(BL);
2771  }
2772
2773  /// Build an empty break statement.
2774  explicit BreakStmt(EmptyShell Empty) : Stmt(BreakStmtClass, Empty) {}
2775
2776  SourceLocation getBreakLoc() const { return BreakStmtBits.BreakLoc; }
2777  void setBreakLoc(SourceLocation L) { BreakStmtBits.BreakLoc = L; }
2778
2779  SourceLocation getBeginLoc() const { return getBreakLoc(); }
2780  SourceLocation getEndLoc() const { return getBreakLoc(); }
2781
2782  static bool classof(const Stmt *T) {
2783    return T->getStmtClass() == BreakStmtClass;
2784  }
2785
2786  // Iterators
2787  child_range children() {
2788    return child_range(child_iterator(), child_iterator());
2789  }
2790
2791  const_child_range children() const {
2792    return const_child_range(const_child_iterator(), const_child_iterator());
2793  }
2794};
2795
2796/// ReturnStmt - This represents a return, optionally of an expression:
2797///   return;
2798///   return 4;
2799///
2800/// Note that GCC allows return with no argument in a function declared to
2801/// return a value, and it allows returning a value in functions declared to
2802/// return void.  We explicitly model this in the AST, which means you can't
2803/// depend on the return type of the function and the presence of an argument.
2804class ReturnStmt final
2805    : public Stmt,
2806      private llvm::TrailingObjects<ReturnStmt, const VarDecl *> {
2807  friend TrailingObjects;
2808
2809  /// The return expression.
2810  Stmt *RetExpr;
2811
2812  // ReturnStmt is followed optionally by a trailing "const VarDecl *"
2813  // for the NRVO candidate. Present if and only if hasNRVOCandidate().
2814
2815  /// True if this ReturnStmt has storage for an NRVO candidate.
2816  bool hasNRVOCandidate() const { return ReturnStmtBits.HasNRVOCandidate; }
2817
2818  unsigned numTrailingObjects(OverloadToken<const VarDecl *>) const {
2819    return hasNRVOCandidate();
2820  }
2821
2822  /// Build a return statement.
2823  ReturnStmt(SourceLocation RL, Expr *E, const VarDecl *NRVOCandidate);
2824
2825  /// Build an empty return statement.
2826  explicit ReturnStmt(EmptyShell Empty, bool HasNRVOCandidate);
2827
2828public:
2829  /// Create a return statement.
2830  static ReturnStmt *Create(const ASTContext &Ctx, SourceLocation RL, Expr *E,
2831                            const VarDecl *NRVOCandidate);
2832
2833  /// Create an empty return statement, optionally with
2834  /// storage for an NRVO candidate.
2835  static ReturnStmt *CreateEmpty(const ASTContext &Ctx, bool HasNRVOCandidate);
2836
2837  Expr *getRetValue() { return reinterpret_cast<Expr *>(RetExpr); }
2838  const Expr *getRetValue() const { return reinterpret_cast<Expr *>(RetExpr); }
2839  void setRetValue(Expr *E) { RetExpr = reinterpret_cast<Stmt *>(E); }
2840
2841  /// Retrieve the variable that might be used for the named return
2842  /// value optimization.
2843  ///
2844  /// The optimization itself can only be performed if the variable is
2845  /// also marked as an NRVO object.
2846  const VarDecl *getNRVOCandidate() const {
2847    return hasNRVOCandidate() ? *getTrailingObjects<const VarDecl *>()
2848                              : nullptr;
2849  }
2850
2851  /// Set the variable that might be used for the named return value
2852  /// optimization. The return statement must have storage for it,
2853  /// which is the case if and only if hasNRVOCandidate() is true.
2854  void setNRVOCandidate(const VarDecl *Var) {
2855    assert(hasNRVOCandidate() &&
2856           "This return statement has no storage for an NRVO candidate!");
2857    *getTrailingObjects<const VarDecl *>() = Var;
2858  }
2859
2860  SourceLocation getReturnLoc() const { return ReturnStmtBits.RetLoc; }
2861  void setReturnLoc(SourceLocation L) { ReturnStmtBits.RetLoc = L; }
2862
2863  SourceLocation getBeginLoc() const { return getReturnLoc(); }
2864  SourceLocation getEndLoc() const LLVM_READONLY {
2865    return RetExpr ? RetExpr->getEndLoc() : getReturnLoc();
2866  }
2867
2868  static bool classof(const Stmt *T) {
2869    return T->getStmtClass() == ReturnStmtClass;
2870  }
2871
2872  // Iterators
2873  child_range children() {
2874    if (RetExpr)
2875      return child_range(&RetExpr, &RetExpr + 1);
2876    return child_range(child_iterator(), child_iterator());
2877  }
2878
2879  const_child_range children() const {
2880    if (RetExpr)
2881      return const_child_range(&RetExpr, &RetExpr + 1);
2882    return const_child_range(const_child_iterator(), const_child_iterator());
2883  }
2884};
2885
2886/// AsmStmt is the base class for GCCAsmStmt and MSAsmStmt.
2887class AsmStmt : public Stmt {
2888protected:
2889  friend class ASTStmtReader;
2890
2891  SourceLocation AsmLoc;
2892
2893  /// True if the assembly statement does not have any input or output
2894  /// operands.
2895  bool IsSimple;
2896
2897  /// If true, treat this inline assembly as having side effects.
2898  /// This assembly statement should not be optimized, deleted or moved.
2899  bool IsVolatile;
2900
2901  unsigned NumOutputs;
2902  unsigned NumInputs;
2903  unsigned NumClobbers;
2904
2905  Stmt **Exprs = nullptr;
2906
2907  AsmStmt(StmtClass SC, SourceLocation asmloc, bool issimple, bool isvolatile,
2908          unsigned numoutputs, unsigned numinputs, unsigned numclobbers)
2909      : Stmt (SC), AsmLoc(asmloc), IsSimple(issimple), IsVolatile(isvolatile),
2910        NumOutputs(numoutputs), NumInputs(numinputs),
2911        NumClobbers(numclobbers) {}
2912
2913public:
2914  /// Build an empty inline-assembly statement.
2915  explicit AsmStmt(StmtClass SC, EmptyShell Empty) : Stmt(SC, Empty) {}
2916
2917  SourceLocation getAsmLoc() const { return AsmLoc; }
2918  void setAsmLoc(SourceLocation L) { AsmLoc = L; }
2919
2920  bool isSimple() const { return IsSimple; }
2921  void setSimple(bool V) { IsSimple = V; }
2922
2923  bool isVolatile() const { return IsVolatile; }
2924  void setVolatile(bool V) { IsVolatile = V; }
2925
2926  SourceLocation getBeginLoc() const LLVM_READONLY { return {}; }
2927  SourceLocation getEndLoc() const LLVM_READONLY { return {}; }
2928
2929  //===--- Asm String Analysis ---===//
2930
2931  /// Assemble final IR asm string.
2932  std::string generateAsmString(const ASTContext &C) const;
2933
2934  //===--- Output operands ---===//
2935
2936  unsigned getNumOutputs() const { return NumOutputs; }
2937
2938  /// getOutputConstraint - Return the constraint string for the specified
2939  /// output operand.  All output constraints are known to be non-empty (either
2940  /// '=' or '+').
2941  StringRef getOutputConstraint(unsigned i) const;
2942
2943  /// isOutputPlusConstraint - Return true if the specified output constraint
2944  /// is a "+" constraint (which is both an input and an output) or false if it
2945  /// is an "=" constraint (just an output).
2946  bool isOutputPlusConstraint(unsigned i) const {
2947    return getOutputConstraint(i)[0] == '+';
2948  }
2949
2950  const Expr *getOutputExpr(unsigned i) const;
2951
2952  /// getNumPlusOperands - Return the number of output operands that have a "+"
2953  /// constraint.
2954  unsigned getNumPlusOperands() const;
2955
2956  //===--- Input operands ---===//
2957
2958  unsigned getNumInputs() const { return NumInputs; }
2959
2960  /// getInputConstraint - Return the specified input constraint.  Unlike output
2961  /// constraints, these can be empty.
2962  StringRef getInputConstraint(unsigned i) const;
2963
2964  const Expr *getInputExpr(unsigned i) const;
2965
2966  //===--- Other ---===//
2967
2968  unsigned getNumClobbers() const { return NumClobbers; }
2969  StringRef getClobber(unsigned i) const;
2970
2971  static bool classof(const Stmt *T) {
2972    return T->getStmtClass() == GCCAsmStmtClass ||
2973      T->getStmtClass() == MSAsmStmtClass;
2974  }
2975
2976  // Input expr iterators.
2977
2978  using inputs_iterator = ExprIterator;
2979  using const_inputs_iterator = ConstExprIterator;
2980  using inputs_range = llvm::iterator_range<inputs_iterator>;
2981  using inputs_const_range = llvm::iterator_range<const_inputs_iterator>;
2982
2983  inputs_iterator begin_inputs() {
2984    return &Exprs[0] + NumOutputs;
2985  }
2986
2987  inputs_iterator end_inputs() {
2988    return &Exprs[0] + NumOutputs + NumInputs;
2989  }
2990
2991  inputs_range inputs() { return inputs_range(begin_inputs(), end_inputs()); }
2992
2993  const_inputs_iterator begin_inputs() const {
2994    return &Exprs[0] + NumOutputs;
2995  }
2996
2997  const_inputs_iterator end_inputs() const {
2998    return &Exprs[0] + NumOutputs + NumInputs;
2999  }
3000
3001  inputs_const_range inputs() const {
3002    return inputs_const_range(begin_inputs(), end_inputs());
3003  }
3004
3005  // Output expr iterators.
3006
3007  using outputs_iterator = ExprIterator;
3008  using const_outputs_iterator = ConstExprIterator;
3009  using outputs_range = llvm::iterator_range<outputs_iterator>;
3010  using outputs_const_range = llvm::iterator_range<const_outputs_iterator>;
3011
3012  outputs_iterator begin_outputs() {
3013    return &Exprs[0];
3014  }
3015
3016  outputs_iterator end_outputs() {
3017    return &Exprs[0] + NumOutputs;
3018  }
3019
3020  outputs_range outputs() {
3021    return outputs_range(begin_outputs(), end_outputs());
3022  }
3023
3024  const_outputs_iterator begin_outputs() const {
3025    return &Exprs[0];
3026  }
3027
3028  const_outputs_iterator end_outputs() const {
3029    return &Exprs[0] + NumOutputs;
3030  }
3031
3032  outputs_const_range outputs() const {
3033    return outputs_const_range(begin_outputs(), end_outputs());
3034  }
3035
3036  child_range children() {
3037    return child_range(&Exprs[0], &Exprs[0] + NumOutputs + NumInputs);
3038  }
3039
3040  const_child_range children() const {
3041    return const_child_range(&Exprs[0], &Exprs[0] + NumOutputs + NumInputs);
3042  }
3043};
3044
3045/// This represents a GCC inline-assembly statement extension.
3046class GCCAsmStmt : public AsmStmt {
3047  friend class ASTStmtReader;
3048
3049  SourceLocation RParenLoc;
3050  StringLiteral *AsmStr;
3051
3052  // FIXME: If we wanted to, we could allocate all of these in one big array.
3053  StringLiteral **Constraints = nullptr;
3054  StringLiteral **Clobbers = nullptr;
3055  IdentifierInfo **Names = nullptr;
3056  unsigned NumLabels = 0;
3057
3058public:
3059  GCCAsmStmt(const ASTContext &C, SourceLocation asmloc, bool issimple,
3060             bool isvolatile, unsigned numoutputs, unsigned numinputs,
3061             IdentifierInfo **names, StringLiteral **constraints, Expr **exprs,
3062             StringLiteral *asmstr, unsigned numclobbers,
3063             StringLiteral **clobbers, unsigned numlabels,
3064             SourceLocation rparenloc);
3065
3066  /// Build an empty inline-assembly statement.
3067  explicit GCCAsmStmt(EmptyShell Empty) : AsmStmt(GCCAsmStmtClass, Empty) {}
3068
3069  SourceLocation getRParenLoc() const { return RParenLoc; }
3070  void setRParenLoc(SourceLocation L) { RParenLoc = L; }
3071
3072  //===--- Asm String Analysis ---===//
3073
3074  const StringLiteral *getAsmString() const { return AsmStr; }
3075  StringLiteral *getAsmString() { return AsmStr; }
3076  void setAsmString(StringLiteral *E) { AsmStr = E; }
3077
3078  /// AsmStringPiece - this is part of a decomposed asm string specification
3079  /// (for use with the AnalyzeAsmString function below).  An asm string is
3080  /// considered to be a concatenation of these parts.
3081  class AsmStringPiece {
3082  public:
3083    enum Kind {
3084      String,  // String in .ll asm string form, "$" -> "$$" and "%%" -> "%".
3085      Operand  // Operand reference, with optional modifier %c4.
3086    };
3087
3088  private:
3089    Kind MyKind;
3090    std::string Str;
3091    unsigned OperandNo;
3092
3093    // Source range for operand references.
3094    CharSourceRange Range;
3095
3096  public:
3097    AsmStringPiece(const std::string &S) : MyKind(String), Str(S) {}
3098    AsmStringPiece(unsigned OpNo, const std::string &S, SourceLocation Begin,
3099                   SourceLocation End)
3100        : MyKind(Operand), Str(S), OperandNo(OpNo),
3101          Range(CharSourceRange::getCharRange(Begin, End)) {}
3102
3103    bool isString() const { return MyKind == String; }
3104    bool isOperand() const { return MyKind == Operand; }
3105
3106    const std::string &getString() const { return Str; }
3107
3108    unsigned getOperandNo() const {
3109      assert(isOperand());
3110      return OperandNo;
3111    }
3112
3113    CharSourceRange getRange() const {
3114      assert(isOperand() && "Range is currently used only for Operands.");
3115      return Range;
3116    }
3117
3118    /// getModifier - Get the modifier for this operand, if present.  This
3119    /// returns '\0' if there was no modifier.
3120    char getModifier() const;
3121  };
3122
3123  /// AnalyzeAsmString - Analyze the asm string of the current asm, decomposing
3124  /// it into pieces.  If the asm string is erroneous, emit errors and return
3125  /// true, otherwise return false.  This handles canonicalization and
3126  /// translation of strings from GCC syntax to LLVM IR syntax, and handles
3127  //// flattening of named references like %[foo] to Operand AsmStringPiece's.
3128  unsigned AnalyzeAsmString(SmallVectorImpl<AsmStringPiece> &Pieces,
3129                            const ASTContext &C, unsigned &DiagOffs) const;
3130
3131  /// Assemble final IR asm string.
3132  std::string generateAsmString(const ASTContext &C) const;
3133
3134  //===--- Output operands ---===//
3135
3136  IdentifierInfo *getOutputIdentifier(unsigned i) const { return Names[i]; }
3137
3138  StringRef getOutputName(unsigned i) const {
3139    if (IdentifierInfo *II = getOutputIdentifier(i))
3140      return II->getName();
3141
3142    return {};
3143  }
3144
3145  StringRef getOutputConstraint(unsigned i) const;
3146
3147  const StringLiteral *getOutputConstraintLiteral(unsigned i) const {
3148    return Constraints[i];
3149  }
3150  StringLiteral *getOutputConstraintLiteral(unsigned i) {
3151    return Constraints[i];
3152  }
3153
3154  Expr *getOutputExpr(unsigned i);
3155
3156  const Expr *getOutputExpr(unsigned i) const {
3157    return const_cast<GCCAsmStmt*>(this)->getOutputExpr(i);
3158  }
3159
3160  //===--- Input operands ---===//
3161
3162  IdentifierInfo *getInputIdentifier(unsigned i) const {
3163    return Names[i + NumOutputs];
3164  }
3165
3166  StringRef getInputName(unsigned i) const {
3167    if (IdentifierInfo *II = getInputIdentifier(i))
3168      return II->getName();
3169
3170    return {};
3171  }
3172
3173  StringRef getInputConstraint(unsigned i) const;
3174
3175  const StringLiteral *getInputConstraintLiteral(unsigned i) const {
3176    return Constraints[i + NumOutputs];
3177  }
3178  StringLiteral *getInputConstraintLiteral(unsigned i) {
3179    return Constraints[i + NumOutputs];
3180  }
3181
3182  Expr *getInputExpr(unsigned i);
3183  void setInputExpr(unsigned i, Expr *E);
3184
3185  const Expr *getInputExpr(unsigned i) const {
3186    return const_cast<GCCAsmStmt*>(this)->getInputExpr(i);
3187  }
3188
3189  //===--- Labels ---===//
3190
3191  bool isAsmGoto() const {
3192    return NumLabels > 0;
3193  }
3194
3195  unsigned getNumLabels() const {
3196    return NumLabels;
3197  }
3198
3199  IdentifierInfo *getLabelIdentifier(unsigned i) const {
3200    return Names[i + NumOutputs + NumInputs];
3201  }
3202
3203  AddrLabelExpr *getLabelExpr(unsigned i) const;
3204  StringRef getLabelName(unsigned i) const;
3205  using labels_iterator = CastIterator<AddrLabelExpr>;
3206  using const_labels_iterator = ConstCastIterator<AddrLabelExpr>;
3207  using labels_range = llvm::iterator_range<labels_iterator>;
3208  using labels_const_range = llvm::iterator_range<const_labels_iterator>;
3209
3210  labels_iterator begin_labels() {
3211    return &Exprs[0] + NumOutputs + NumInputs;
3212  }
3213
3214  labels_iterator end_labels() {
3215    return &Exprs[0] + NumOutputs + NumInputs + NumLabels;
3216  }
3217
3218  labels_range labels() {
3219    return labels_range(begin_labels(), end_labels());
3220  }
3221
3222  const_labels_iterator begin_labels() const {
3223    return &Exprs[0] + NumOutputs + NumInputs;
3224  }
3225
3226  const_labels_iterator end_labels() const {
3227    return &Exprs[0] + NumOutputs + NumInputs + NumLabels;
3228  }
3229
3230  labels_const_range labels() const {
3231    return labels_const_range(begin_labels(), end_labels());
3232  }
3233
3234private:
3235  void setOutputsAndInputsAndClobbers(const ASTContext &C,
3236                                      IdentifierInfo **Names,
3237                                      StringLiteral **Constraints,
3238                                      Stmt **Exprs,
3239                                      unsigned NumOutputs,
3240                                      unsigned NumInputs,
3241                                      unsigned NumLabels,
3242                                      StringLiteral **Clobbers,
3243                                      unsigned NumClobbers);
3244
3245public:
3246  //===--- Other ---===//
3247
3248  /// getNamedOperand - Given a symbolic operand reference like %[foo],
3249  /// translate this into a numeric value needed to reference the same operand.
3250  /// This returns -1 if the operand name is invalid.
3251  int getNamedOperand(StringRef SymbolicName) const;
3252
3253  StringRef getClobber(unsigned i) const;
3254
3255  StringLiteral *getClobberStringLiteral(unsigned i) { return Clobbers[i]; }
3256  const StringLiteral *getClobberStringLiteral(unsigned i) const {
3257    return Clobbers[i];
3258  }
3259
3260  SourceLocation getBeginLoc() const LLVM_READONLY { return AsmLoc; }
3261  SourceLocation getEndLoc() const LLVM_READONLY { return RParenLoc; }
3262
3263  static bool classof(const Stmt *T) {
3264    return T->getStmtClass() == GCCAsmStmtClass;
3265  }
3266};
3267
3268/// This represents a Microsoft inline-assembly statement extension.
3269class MSAsmStmt : public AsmStmt {
3270  friend class ASTStmtReader;
3271
3272  SourceLocation LBraceLoc, EndLoc;
3273  StringRef AsmStr;
3274
3275  unsigned NumAsmToks = 0;
3276
3277  Token *AsmToks = nullptr;
3278  StringRef *Constraints = nullptr;
3279  StringRef *Clobbers = nullptr;
3280
3281public:
3282  MSAsmStmt(const ASTContext &C, SourceLocation asmloc,
3283            SourceLocation lbraceloc, bool issimple, bool isvolatile,
3284            ArrayRef<Token> asmtoks, unsigned numoutputs, unsigned numinputs,
3285            ArrayRef<StringRef> constraints,
3286            ArrayRef<Expr*> exprs, StringRef asmstr,
3287            ArrayRef<StringRef> clobbers, SourceLocation endloc);
3288
3289  /// Build an empty MS-style inline-assembly statement.
3290  explicit MSAsmStmt(EmptyShell Empty) : AsmStmt(MSAsmStmtClass, Empty) {}
3291
3292  SourceLocation getLBraceLoc() const { return LBraceLoc; }
3293  void setLBraceLoc(SourceLocation L) { LBraceLoc = L; }
3294  SourceLocation getEndLoc() const { return EndLoc; }
3295  void setEndLoc(SourceLocation L) { EndLoc = L; }
3296
3297  bool hasBraces() const { return LBraceLoc.isValid(); }
3298
3299  unsigned getNumAsmToks() { return NumAsmToks; }
3300  Token *getAsmToks() { return AsmToks; }
3301
3302  //===--- Asm String Analysis ---===//
3303  StringRef getAsmString() const { return AsmStr; }
3304
3305  /// Assemble final IR asm string.
3306  std::string generateAsmString(const ASTContext &C) const;
3307
3308  //===--- Output operands ---===//
3309
3310  StringRef getOutputConstraint(unsigned i) const {
3311    assert(i < NumOutputs);
3312    return Constraints[i];
3313  }
3314
3315  Expr *getOutputExpr(unsigned i);
3316
3317  const Expr *getOutputExpr(unsigned i) const {
3318    return const_cast<MSAsmStmt*>(this)->getOutputExpr(i);
3319  }
3320
3321  //===--- Input operands ---===//
3322
3323  StringRef getInputConstraint(unsigned i) const {
3324    assert(i < NumInputs);
3325    return Constraints[i + NumOutputs];
3326  }
3327
3328  Expr *getInputExpr(unsigned i);
3329  void setInputExpr(unsigned i, Expr *E);
3330
3331  const Expr *getInputExpr(unsigned i) const {
3332    return const_cast<MSAsmStmt*>(this)->getInputExpr(i);
3333  }
3334
3335  //===--- Other ---===//
3336
3337  ArrayRef<StringRef> getAllConstraints() const {
3338    return llvm::ArrayRef(Constraints, NumInputs + NumOutputs);
3339  }
3340
3341  ArrayRef<StringRef> getClobbers() const {
3342    return llvm::ArrayRef(Clobbers, NumClobbers);
3343  }
3344
3345  ArrayRef<Expr*> getAllExprs() const {
3346    return llvm::ArrayRef(reinterpret_cast<Expr **>(Exprs),
3347                          NumInputs + NumOutputs);
3348  }
3349
3350  StringRef getClobber(unsigned i) const { return getClobbers()[i]; }
3351
3352private:
3353  void initialize(const ASTContext &C, StringRef AsmString,
3354                  ArrayRef<Token> AsmToks, ArrayRef<StringRef> Constraints,
3355                  ArrayRef<Expr*> Exprs, ArrayRef<StringRef> Clobbers);
3356
3357public:
3358  SourceLocation getBeginLoc() const LLVM_READONLY { return AsmLoc; }
3359
3360  static bool classof(const Stmt *T) {
3361    return T->getStmtClass() == MSAsmStmtClass;
3362  }
3363
3364  child_range children() {
3365    return child_range(&Exprs[0], &Exprs[NumInputs + NumOutputs]);
3366  }
3367
3368  const_child_range children() const {
3369    return const_child_range(&Exprs[0], &Exprs[NumInputs + NumOutputs]);
3370  }
3371};
3372
3373class SEHExceptStmt : public Stmt {
3374  friend class ASTReader;
3375  friend class ASTStmtReader;
3376
3377  SourceLocation  Loc;
3378  Stmt *Children[2];
3379
3380  enum { FILTER_EXPR, BLOCK };
3381
3382  SEHExceptStmt(SourceLocation Loc, Expr *FilterExpr, Stmt *Block);
3383  explicit SEHExceptStmt(EmptyShell E) : Stmt(SEHExceptStmtClass, E) {}
3384
3385public:
3386  static SEHExceptStmt* Create(const ASTContext &C,
3387                               SourceLocation ExceptLoc,
3388                               Expr *FilterExpr,
3389                               Stmt *Block);
3390
3391  SourceLocation getBeginLoc() const LLVM_READONLY { return getExceptLoc(); }
3392
3393  SourceLocation getExceptLoc() const { return Loc; }
3394  SourceLocation getEndLoc() const { return getBlock()->getEndLoc(); }
3395
3396  Expr *getFilterExpr() const {
3397    return reinterpret_cast<Expr*>(Children[FILTER_EXPR]);
3398  }
3399
3400  CompoundStmt *getBlock() const {
3401    return cast<CompoundStmt>(Children[BLOCK]);
3402  }
3403
3404  child_range children() {
3405    return child_range(Children, Children+2);
3406  }
3407
3408  const_child_range children() const {
3409    return const_child_range(Children, Children + 2);
3410  }
3411
3412  static bool classof(const Stmt *T) {
3413    return T->getStmtClass() == SEHExceptStmtClass;
3414  }
3415};
3416
3417class SEHFinallyStmt : public Stmt {
3418  friend class ASTReader;
3419  friend class ASTStmtReader;
3420
3421  SourceLocation  Loc;
3422  Stmt *Block;
3423
3424  SEHFinallyStmt(SourceLocation Loc, Stmt *Block);
3425  explicit SEHFinallyStmt(EmptyShell E) : Stmt(SEHFinallyStmtClass, E) {}
3426
3427public:
3428  static SEHFinallyStmt* Create(const ASTContext &C,
3429                                SourceLocation FinallyLoc,
3430                                Stmt *Block);
3431
3432  SourceLocation getBeginLoc() const LLVM_READONLY { return getFinallyLoc(); }
3433
3434  SourceLocation getFinallyLoc() const { return Loc; }
3435  SourceLocation getEndLoc() const { return Block->getEndLoc(); }
3436
3437  CompoundStmt *getBlock() const { return cast<CompoundStmt>(Block); }
3438
3439  child_range children() {
3440    return child_range(&Block,&Block+1);
3441  }
3442
3443  const_child_range children() const {
3444    return const_child_range(&Block, &Block + 1);
3445  }
3446
3447  static bool classof(const Stmt *T) {
3448    return T->getStmtClass() == SEHFinallyStmtClass;
3449  }
3450};
3451
3452class SEHTryStmt : public Stmt {
3453  friend class ASTReader;
3454  friend class ASTStmtReader;
3455
3456  bool IsCXXTry;
3457  SourceLocation  TryLoc;
3458  Stmt *Children[2];
3459
3460  enum { TRY = 0, HANDLER = 1 };
3461
3462  SEHTryStmt(bool isCXXTry, // true if 'try' otherwise '__try'
3463             SourceLocation TryLoc,
3464             Stmt *TryBlock,
3465             Stmt *Handler);
3466
3467  explicit SEHTryStmt(EmptyShell E) : Stmt(SEHTryStmtClass, E) {}
3468
3469public:
3470  static SEHTryStmt* Create(const ASTContext &C, bool isCXXTry,
3471                            SourceLocation TryLoc, Stmt *TryBlock,
3472                            Stmt *Handler);
3473
3474  SourceLocation getBeginLoc() const LLVM_READONLY { return getTryLoc(); }
3475
3476  SourceLocation getTryLoc() const { return TryLoc; }
3477  SourceLocation getEndLoc() const { return Children[HANDLER]->getEndLoc(); }
3478
3479  bool getIsCXXTry() const { return IsCXXTry; }
3480
3481  CompoundStmt* getTryBlock() const {
3482    return cast<CompoundStmt>(Children[TRY]);
3483  }
3484
3485  Stmt *getHandler() const { return Children[HANDLER]; }
3486
3487  /// Returns 0 if not defined
3488  SEHExceptStmt  *getExceptHandler() const;
3489  SEHFinallyStmt *getFinallyHandler() const;
3490
3491  child_range children() {
3492    return child_range(Children, Children+2);
3493  }
3494
3495  const_child_range children() const {
3496    return const_child_range(Children, Children + 2);
3497  }
3498
3499  static bool classof(const Stmt *T) {
3500    return T->getStmtClass() == SEHTryStmtClass;
3501  }
3502};
3503
3504/// Represents a __leave statement.
3505class SEHLeaveStmt : public Stmt {
3506  SourceLocation LeaveLoc;
3507
3508public:
3509  explicit SEHLeaveStmt(SourceLocation LL)
3510      : Stmt(SEHLeaveStmtClass), LeaveLoc(LL) {}
3511
3512  /// Build an empty __leave statement.
3513  explicit SEHLeaveStmt(EmptyShell Empty) : Stmt(SEHLeaveStmtClass, Empty) {}
3514
3515  SourceLocation getLeaveLoc() const { return LeaveLoc; }
3516  void setLeaveLoc(SourceLocation L) { LeaveLoc = L; }
3517
3518  SourceLocation getBeginLoc() const LLVM_READONLY { return LeaveLoc; }
3519  SourceLocation getEndLoc() const LLVM_READONLY { return LeaveLoc; }
3520
3521  static bool classof(const Stmt *T) {
3522    return T->getStmtClass() == SEHLeaveStmtClass;
3523  }
3524
3525  // Iterators
3526  child_range children() {
3527    return child_range(child_iterator(), child_iterator());
3528  }
3529
3530  const_child_range children() const {
3531    return const_child_range(const_child_iterator(), const_child_iterator());
3532  }
3533};
3534
3535/// This captures a statement into a function. For example, the following
3536/// pragma annotated compound statement can be represented as a CapturedStmt,
3537/// and this compound statement is the body of an anonymous outlined function.
3538/// @code
3539/// #pragma omp parallel
3540/// {
3541///   compute();
3542/// }
3543/// @endcode
3544class CapturedStmt : public Stmt {
3545public:
3546  /// The different capture forms: by 'this', by reference, capture for
3547  /// variable-length array type etc.
3548  enum VariableCaptureKind {
3549    VCK_This,
3550    VCK_ByRef,
3551    VCK_ByCopy,
3552    VCK_VLAType,
3553  };
3554
3555  /// Describes the capture of either a variable, or 'this', or
3556  /// variable-length array type.
3557  class Capture {
3558    llvm::PointerIntPair<VarDecl *, 2, VariableCaptureKind> VarAndKind;
3559    SourceLocation Loc;
3560
3561  public:
3562    friend class ASTStmtReader;
3563
3564    /// Create a new capture.
3565    ///
3566    /// \param Loc The source location associated with this capture.
3567    ///
3568    /// \param Kind The kind of capture (this, ByRef, ...).
3569    ///
3570    /// \param Var The variable being captured, or null if capturing this.
3571    Capture(SourceLocation Loc, VariableCaptureKind Kind,
3572            VarDecl *Var = nullptr);
3573
3574    /// Determine the kind of capture.
3575    VariableCaptureKind getCaptureKind() const;
3576
3577    /// Retrieve the source location at which the variable or 'this' was
3578    /// first used.
3579    SourceLocation getLocation() const { return Loc; }
3580
3581    /// Determine whether this capture handles the C++ 'this' pointer.
3582    bool capturesThis() const { return getCaptureKind() == VCK_This; }
3583
3584    /// Determine whether this capture handles a variable (by reference).
3585    bool capturesVariable() const { return getCaptureKind() == VCK_ByRef; }
3586
3587    /// Determine whether this capture handles a variable by copy.
3588    bool capturesVariableByCopy() const {
3589      return getCaptureKind() == VCK_ByCopy;
3590    }
3591
3592    /// Determine whether this capture handles a variable-length array
3593    /// type.
3594    bool capturesVariableArrayType() const {
3595      return getCaptureKind() == VCK_VLAType;
3596    }
3597
3598    /// Retrieve the declaration of the variable being captured.
3599    ///
3600    /// This operation is only valid if this capture captures a variable.
3601    VarDecl *getCapturedVar() const;
3602  };
3603
3604private:
3605  /// The number of variable captured, including 'this'.
3606  unsigned NumCaptures;
3607
3608  /// The pointer part is the implicit the outlined function and the
3609  /// int part is the captured region kind, 'CR_Default' etc.
3610  llvm::PointerIntPair<CapturedDecl *, 2, CapturedRegionKind> CapDeclAndKind;
3611
3612  /// The record for captured variables, a RecordDecl or CXXRecordDecl.
3613  RecordDecl *TheRecordDecl = nullptr;
3614
3615  /// Construct a captured statement.
3616  CapturedStmt(Stmt *S, CapturedRegionKind Kind, ArrayRef<Capture> Captures,
3617               ArrayRef<Expr *> CaptureInits, CapturedDecl *CD, RecordDecl *RD);
3618
3619  /// Construct an empty captured statement.
3620  CapturedStmt(EmptyShell Empty, unsigned NumCaptures);
3621
3622  Stmt **getStoredStmts() { return reinterpret_cast<Stmt **>(this + 1); }
3623
3624  Stmt *const *getStoredStmts() const {
3625    return reinterpret_cast<Stmt *const *>(this + 1);
3626  }
3627
3628  Capture *getStoredCaptures() const;
3629
3630  void setCapturedStmt(Stmt *S) { getStoredStmts()[NumCaptures] = S; }
3631
3632public:
3633  friend class ASTStmtReader;
3634
3635  static CapturedStmt *Create(const ASTContext &Context, Stmt *S,
3636                              CapturedRegionKind Kind,
3637                              ArrayRef<Capture> Captures,
3638                              ArrayRef<Expr *> CaptureInits,
3639                              CapturedDecl *CD, RecordDecl *RD);
3640
3641  static CapturedStmt *CreateDeserialized(const ASTContext &Context,
3642                                          unsigned NumCaptures);
3643
3644  /// Retrieve the statement being captured.
3645  Stmt *getCapturedStmt() { return getStoredStmts()[NumCaptures]; }
3646  const Stmt *getCapturedStmt() const { return getStoredStmts()[NumCaptures]; }
3647
3648  /// Retrieve the outlined function declaration.
3649  CapturedDecl *getCapturedDecl();
3650  const CapturedDecl *getCapturedDecl() const;
3651
3652  /// Set the outlined function declaration.
3653  void setCapturedDecl(CapturedDecl *D);
3654
3655  /// Retrieve the captured region kind.
3656  CapturedRegionKind getCapturedRegionKind() const;
3657
3658  /// Set the captured region kind.
3659  void setCapturedRegionKind(CapturedRegionKind Kind);
3660
3661  /// Retrieve the record declaration for captured variables.
3662  const RecordDecl *getCapturedRecordDecl() const { return TheRecordDecl; }
3663
3664  /// Set the record declaration for captured variables.
3665  void setCapturedRecordDecl(RecordDecl *D) {
3666    assert(D && "null RecordDecl");
3667    TheRecordDecl = D;
3668  }
3669
3670  /// True if this variable has been captured.
3671  bool capturesVariable(const VarDecl *Var) const;
3672
3673  /// An iterator that walks over the captures.
3674  using capture_iterator = Capture *;
3675  using const_capture_iterator = const Capture *;
3676  using capture_range = llvm::iterator_range<capture_iterator>;
3677  using capture_const_range = llvm::iterator_range<const_capture_iterator>;
3678
3679  capture_range captures() {
3680    return capture_range(capture_begin(), capture_end());
3681  }
3682  capture_const_range captures() const {
3683    return capture_const_range(capture_begin(), capture_end());
3684  }
3685
3686  /// Retrieve an iterator pointing to the first capture.
3687  capture_iterator capture_begin() { return getStoredCaptures(); }
3688  const_capture_iterator capture_begin() const { return getStoredCaptures(); }
3689
3690  /// Retrieve an iterator pointing past the end of the sequence of
3691  /// captures.
3692  capture_iterator capture_end() const {
3693    return getStoredCaptures() + NumCaptures;
3694  }
3695
3696  /// Retrieve the number of captures, including 'this'.
3697  unsigned capture_size() const { return NumCaptures; }
3698
3699  /// Iterator that walks over the capture initialization arguments.
3700  using capture_init_iterator = Expr **;
3701  using capture_init_range = llvm::iterator_range<capture_init_iterator>;
3702
3703  /// Const iterator that walks over the capture initialization
3704  /// arguments.
3705  using const_capture_init_iterator = Expr *const *;
3706  using const_capture_init_range =
3707      llvm::iterator_range<const_capture_init_iterator>;
3708
3709  capture_init_range capture_inits() {
3710    return capture_init_range(capture_init_begin(), capture_init_end());
3711  }
3712
3713  const_capture_init_range capture_inits() const {
3714    return const_capture_init_range(capture_init_begin(), capture_init_end());
3715  }
3716
3717  /// Retrieve the first initialization argument.
3718  capture_init_iterator capture_init_begin() {
3719    return reinterpret_cast<Expr **>(getStoredStmts());
3720  }
3721
3722  const_capture_init_iterator capture_init_begin() const {
3723    return reinterpret_cast<Expr *const *>(getStoredStmts());
3724  }
3725
3726  /// Retrieve the iterator pointing one past the last initialization
3727  /// argument.
3728  capture_init_iterator capture_init_end() {
3729    return capture_init_begin() + NumCaptures;
3730  }
3731
3732  const_capture_init_iterator capture_init_end() const {
3733    return capture_init_begin() + NumCaptures;
3734  }
3735
3736  SourceLocation getBeginLoc() const LLVM_READONLY {
3737    return getCapturedStmt()->getBeginLoc();
3738  }
3739
3740  SourceLocation getEndLoc() const LLVM_READONLY {
3741    return getCapturedStmt()->getEndLoc();
3742  }
3743
3744  SourceRange getSourceRange() const LLVM_READONLY {
3745    return getCapturedStmt()->getSourceRange();
3746  }
3747
3748  static bool classof(const Stmt *T) {
3749    return T->getStmtClass() == CapturedStmtClass;
3750  }
3751
3752  child_range children();
3753
3754  const_child_range children() const;
3755};
3756
3757} // namespace clang
3758
3759#endif // LLVM_CLANG_AST_STMT_H
3760