Coverage Report

Created: 2022-07-16 07:03

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/lib/AST/RecordLayoutBuilder.cpp
Line
Count
Source (jump to first uncovered line)
1
//=== RecordLayoutBuilder.cpp - Helper class for building record layouts ---==//
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
#include "clang/AST/ASTContext.h"
10
#include "clang/AST/ASTDiagnostic.h"
11
#include "clang/AST/Attr.h"
12
#include "clang/AST/CXXInheritance.h"
13
#include "clang/AST/Decl.h"
14
#include "clang/AST/DeclCXX.h"
15
#include "clang/AST/DeclObjC.h"
16
#include "clang/AST/Expr.h"
17
#include "clang/AST/VTableBuilder.h"
18
#include "clang/AST/RecordLayout.h"
19
#include "clang/Basic/TargetInfo.h"
20
#include "llvm/ADT/SmallSet.h"
21
#include "llvm/Support/Format.h"
22
#include "llvm/Support/MathExtras.h"
23
24
using namespace clang;
25
26
namespace {
27
28
/// BaseSubobjectInfo - Represents a single base subobject in a complete class.
29
/// For a class hierarchy like
30
///
31
/// class A { };
32
/// class B : A { };
33
/// class C : A, B { };
34
///
35
/// The BaseSubobjectInfo graph for C will have three BaseSubobjectInfo
36
/// instances, one for B and two for A.
37
///
38
/// If a base is virtual, it will only have one BaseSubobjectInfo allocated.
39
struct BaseSubobjectInfo {
40
  /// Class - The class for this base info.
41
  const CXXRecordDecl *Class;
42
43
  /// IsVirtual - Whether the BaseInfo represents a virtual base or not.
44
  bool IsVirtual;
45
46
  /// Bases - Information about the base subobjects.
47
  SmallVector<BaseSubobjectInfo*, 4> Bases;
48
49
  /// PrimaryVirtualBaseInfo - Holds the base info for the primary virtual base
50
  /// of this base info (if one exists).
51
  BaseSubobjectInfo *PrimaryVirtualBaseInfo;
52
53
  // FIXME: Document.
54
  const BaseSubobjectInfo *Derived;
55
};
56
57
/// Externally provided layout. Typically used when the AST source, such
58
/// as DWARF, lacks all the information that was available at compile time, such
59
/// as alignment attributes on fields and pragmas in effect.
60
struct ExternalLayout {
61
421k
  ExternalLayout() : Size(0), Align(0) {}
62
63
  /// Overall record size in bits.
64
  uint64_t Size;
65
66
  /// Overall record alignment in bits.
67
  uint64_t Align;
68
69
  /// Record field offsets in bits.
70
  llvm::DenseMap<const FieldDecl *, uint64_t> FieldOffsets;
71
72
  /// Direct, non-virtual base offsets.
73
  llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsets;
74
75
  /// Virtual base offsets.
76
  llvm::DenseMap<const CXXRecordDecl *, CharUnits> VirtualBaseOffsets;
77
78
  /// Get the offset of the given field. The external source must provide
79
  /// entries for all fields in the record.
80
33.8k
  uint64_t getExternalFieldOffset(const FieldDecl *FD) {
81
33.8k
    assert(FieldOffsets.count(FD) &&
82
33.8k
           "Field does not have an external offset");
83
0
    return FieldOffsets[FD];
84
33.8k
  }
85
86
14.5k
  bool getExternalNVBaseOffset(const CXXRecordDecl *RD, CharUnits &BaseOffset) {
87
14.5k
    auto Known = BaseOffsets.find(RD);
88
14.5k
    if (Known == BaseOffsets.end())
89
10
      return false;
90
14.5k
    BaseOffset = Known->second;
91
14.5k
    return true;
92
14.5k
  }
93
94
25
  bool getExternalVBaseOffset(const CXXRecordDecl *RD, CharUnits &BaseOffset) {
95
25
    auto Known = VirtualBaseOffsets.find(RD);
96
25
    if (Known == VirtualBaseOffsets.end())
97
9
      return false;
98
16
    BaseOffset = Known->second;
99
16
    return true;
100
25
  }
101
};
102
103
/// EmptySubobjectMap - Keeps track of which empty subobjects exist at different
104
/// offsets while laying out a C++ class.
105
class EmptySubobjectMap {
106
  const ASTContext &Context;
107
  uint64_t CharWidth;
108
109
  /// Class - The class whose empty entries we're keeping track of.
110
  const CXXRecordDecl *Class;
111
112
  /// EmptyClassOffsets - A map from offsets to empty record decls.
113
  typedef llvm::TinyPtrVector<const CXXRecordDecl *> ClassVectorTy;
114
  typedef llvm::DenseMap<CharUnits, ClassVectorTy> EmptyClassOffsetsMapTy;
115
  EmptyClassOffsetsMapTy EmptyClassOffsets;
116
117
  /// MaxEmptyClassOffset - The highest offset known to contain an empty
118
  /// base subobject.
119
  CharUnits MaxEmptyClassOffset;
120
121
  /// ComputeEmptySubobjectSizes - Compute the size of the largest base or
122
  /// member subobject that is empty.
123
  void ComputeEmptySubobjectSizes();
124
125
  void AddSubobjectAtOffset(const CXXRecordDecl *RD, CharUnits Offset);
126
127
  void UpdateEmptyBaseSubobjects(const BaseSubobjectInfo *Info,
128
                                 CharUnits Offset, bool PlacingEmptyBase);
129
130
  void UpdateEmptyFieldSubobjects(const CXXRecordDecl *RD,
131
                                  const CXXRecordDecl *Class, CharUnits Offset,
132
                                  bool PlacingOverlappingField);
133
  void UpdateEmptyFieldSubobjects(const FieldDecl *FD, CharUnits Offset,
134
                                  bool PlacingOverlappingField);
135
136
  /// AnyEmptySubobjectsBeyondOffset - Returns whether there are any empty
137
  /// subobjects beyond the given offset.
138
1.71M
  bool AnyEmptySubobjectsBeyondOffset(CharUnits Offset) const {
139
1.71M
    return Offset <= MaxEmptyClassOffset;
140
1.71M
  }
141
142
  CharUnits
143
211k
  getFieldOffset(const ASTRecordLayout &Layout, unsigned FieldNo) const {
144
211k
    uint64_t FieldOffset = Layout.getFieldOffset(FieldNo);
145
211k
    assert(FieldOffset % CharWidth == 0 &&
146
211k
           "Field offset not at char boundary!");
147
148
0
    return Context.toCharUnitsFromBits(FieldOffset);
149
211k
  }
150
151
protected:
152
  bool CanPlaceSubobjectAtOffset(const CXXRecordDecl *RD,
153
                                 CharUnits Offset) const;
154
155
  bool CanPlaceBaseSubobjectAtOffset(const BaseSubobjectInfo *Info,
156
                                     CharUnits Offset);
157
158
  bool CanPlaceFieldSubobjectAtOffset(const CXXRecordDecl *RD,
159
                                      const CXXRecordDecl *Class,
160
                                      CharUnits Offset) const;
161
  bool CanPlaceFieldSubobjectAtOffset(const FieldDecl *FD,
162
                                      CharUnits Offset) const;
163
164
public:
165
  /// This holds the size of the largest empty subobject (either a base
166
  /// or a member). Will be zero if the record being built doesn't contain
167
  /// any empty classes.
168
  CharUnits SizeOfLargestEmptySubobject;
169
170
  EmptySubobjectMap(const ASTContext &Context, const CXXRecordDecl *Class)
171
294k
  : Context(Context), CharWidth(Context.getCharWidth()), Class(Class) {
172
294k
      ComputeEmptySubobjectSizes();
173
294k
  }
174
175
  /// CanPlaceBaseAtOffset - Return whether the given base class can be placed
176
  /// at the given offset.
177
  /// Returns false if placing the record will result in two components
178
  /// (direct or indirect) of the same type having the same offset.
179
  bool CanPlaceBaseAtOffset(const BaseSubobjectInfo *Info,
180
                            CharUnits Offset);
181
182
  /// CanPlaceFieldAtOffset - Return whether a field can be placed at the given
183
  /// offset.
184
  bool CanPlaceFieldAtOffset(const FieldDecl *FD, CharUnits Offset);
185
};
186
187
294k
void EmptySubobjectMap::ComputeEmptySubobjectSizes() {
188
  // Check the bases.
189
294k
  for (const CXXBaseSpecifier &Base : Class->bases()) {
190
69.9k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
191
192
69.9k
    CharUnits EmptySize;
193
69.9k
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
194
69.9k
    if (BaseDecl->isEmpty()) {
195
      // If the class decl is empty, get its size.
196
41.6k
      EmptySize = Layout.getSize();
197
41.6k
    } else {
198
      // Otherwise, we get the largest empty subobject for the decl.
199
28.3k
      EmptySize = Layout.getSizeOfLargestEmptySubobject();
200
28.3k
    }
201
202
69.9k
    if (EmptySize > SizeOfLargestEmptySubobject)
203
44.8k
      SizeOfLargestEmptySubobject = EmptySize;
204
69.9k
  }
205
206
  // Check the fields.
207
428k
  for (const FieldDecl *FD : Class->fields()) {
208
428k
    const RecordType *RT =
209
428k
        Context.getBaseElementType(FD->getType())->getAs<RecordType>();
210
211
    // We only care about record types.
212
428k
    if (!RT)
213
352k
      continue;
214
215
76.0k
    CharUnits EmptySize;
216
76.0k
    const CXXRecordDecl *MemberDecl = RT->getAsCXXRecordDecl();
217
76.0k
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(MemberDecl);
218
76.0k
    if (MemberDecl->isEmpty()) {
219
      // If the class decl is empty, get its size.
220
1.93k
      EmptySize = Layout.getSize();
221
74.1k
    } else {
222
      // Otherwise, we get the largest empty subobject for the decl.
223
74.1k
      EmptySize = Layout.getSizeOfLargestEmptySubobject();
224
74.1k
    }
225
226
76.0k
    if (EmptySize > SizeOfLargestEmptySubobject)
227
9.91k
      SizeOfLargestEmptySubobject = EmptySize;
228
76.0k
  }
229
294k
}
230
231
bool
232
EmptySubobjectMap::CanPlaceSubobjectAtOffset(const CXXRecordDecl *RD,
233
1.17M
                                             CharUnits Offset) const {
234
  // We only need to check empty bases.
235
1.17M
  if (!RD->isEmpty())
236
601k
    return true;
237
238
573k
  EmptyClassOffsetsMapTy::const_iterator I = EmptyClassOffsets.find(Offset);
239
573k
  if (I == EmptyClassOffsets.end())
240
572k
    return true;
241
242
1.11k
  const ClassVectorTy &Classes = I->second;
243
1.11k
  if (!llvm::is_contained(Classes, RD))
244
867
    return true;
245
246
  // There is already an empty class of the same type at this offset.
247
249
  return false;
248
1.11k
}
249
250
void EmptySubobjectMap::AddSubobjectAtOffset(const CXXRecordDecl *RD,
251
1.14M
                                             CharUnits Offset) {
252
  // We only care about empty bases.
253
1.14M
  if (!RD->isEmpty())
254
567k
    return;
255
256
  // If we have empty structures inside a union, we can assign both
257
  // the same offset. Just avoid pushing them twice in the list.
258
573k
  ClassVectorTy &Classes = EmptyClassOffsets[Offset];
259
573k
  if (llvm::is_contained(Classes, RD))
260
1
    return;
261
262
573k
  Classes.push_back(RD);
263
264
  // Update the empty class offset.
265
573k
  if (Offset > MaxEmptyClassOffset)
266
228
    MaxEmptyClassOffset = Offset;
267
573k
}
268
269
bool
270
EmptySubobjectMap::CanPlaceBaseSubobjectAtOffset(const BaseSubobjectInfo *Info,
271
1.09M
                                                 CharUnits Offset) {
272
  // We don't have to keep looking past the maximum offset that's known to
273
  // contain an empty class.
274
1.09M
  if (!AnyEmptySubobjectsBeyondOffset(Offset))
275
693
    return true;
276
277
1.09M
  if (!CanPlaceSubobjectAtOffset(Info->Class, Offset))
278
172
    return false;
279
280
  // Traverse all non-virtual bases.
281
1.09M
  const ASTRecordLayout &Layout = Context.getASTRecordLayout(Info->Class);
282
1.09M
  for (const BaseSubobjectInfo *Base : Info->Bases) {
283
1.04M
    if (Base->IsVirtual)
284
263
      continue;
285
286
1.04M
    CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base->Class);
287
288
1.04M
    if (!CanPlaceBaseSubobjectAtOffset(Base, BaseOffset))
289
115
      return false;
290
1.04M
  }
291
292
1.09M
  if (Info->PrimaryVirtualBaseInfo) {
293
40
    BaseSubobjectInfo *PrimaryVirtualBaseInfo = Info->PrimaryVirtualBaseInfo;
294
295
40
    if (Info == PrimaryVirtualBaseInfo->Derived) {
296
40
      if (!CanPlaceBaseSubobjectAtOffset(PrimaryVirtualBaseInfo, Offset))
297
9
        return false;
298
40
    }
299
40
  }
300
301
  // Traverse all member variables.
302
1.09M
  unsigned FieldNo = 0;
303
1.09M
  for (CXXRecordDecl::field_iterator I = Info->Class->field_begin(),
304
1.11M
       E = Info->Class->field_end(); I != E; 
++I, ++FieldNo14.5k
) {
305
14.5k
    if (I->isBitField())
306
4
      continue;
307
308
14.5k
    CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
309
14.5k
    if (!CanPlaceFieldSubobjectAtOffset(*I, FieldOffset))
310
2
      return false;
311
14.5k
  }
312
313
1.09M
  return true;
314
1.09M
}
315
316
void EmptySubobjectMap::UpdateEmptyBaseSubobjects(const BaseSubobjectInfo *Info,
317
                                                  CharUnits Offset,
318
1.09M
                                                  bool PlacingEmptyBase) {
319
1.09M
  if (!PlacingEmptyBase && 
Offset >= SizeOfLargestEmptySubobject536k
) {
320
    // We know that the only empty subobjects that can conflict with empty
321
    // subobject of non-empty bases, are empty bases that can be placed at
322
    // offset zero. Because of this, we only need to keep track of empty base
323
    // subobjects with offsets less than the size of the largest empty
324
    // subobject for our class.
325
581
    return;
326
581
  }
327
328
1.09M
  AddSubobjectAtOffset(Info->Class, Offset);
329
330
  // Traverse all non-virtual bases.
331
1.09M
  const ASTRecordLayout &Layout = Context.getASTRecordLayout(Info->Class);
332
1.09M
  for (const BaseSubobjectInfo *Base : Info->Bases) {
333
1.04M
    if (Base->IsVirtual)
334
254
      continue;
335
336
1.04M
    CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base->Class);
337
1.04M
    UpdateEmptyBaseSubobjects(Base, BaseOffset, PlacingEmptyBase);
338
1.04M
  }
339
340
1.09M
  if (Info->PrimaryVirtualBaseInfo) {
341
31
    BaseSubobjectInfo *PrimaryVirtualBaseInfo = Info->PrimaryVirtualBaseInfo;
342
343
31
    if (Info == PrimaryVirtualBaseInfo->Derived)
344
31
      UpdateEmptyBaseSubobjects(PrimaryVirtualBaseInfo, Offset,
345
31
                                PlacingEmptyBase);
346
31
  }
347
348
  // Traverse all member variables.
349
1.09M
  unsigned FieldNo = 0;
350
1.09M
  for (CXXRecordDecl::field_iterator I = Info->Class->field_begin(),
351
1.11M
       E = Info->Class->field_end(); I != E; 
++I, ++FieldNo14.5k
) {
352
14.5k
    if (I->isBitField())
353
4
      continue;
354
355
14.5k
    CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
356
14.5k
    UpdateEmptyFieldSubobjects(*I, FieldOffset, PlacingEmptyBase);
357
14.5k
  }
358
1.09M
}
359
360
bool EmptySubobjectMap::CanPlaceBaseAtOffset(const BaseSubobjectInfo *Info,
361
70.5k
                                             CharUnits Offset) {
362
  // If we know this class doesn't have any empty subobjects we don't need to
363
  // bother checking.
364
70.5k
  if (SizeOfLargestEmptySubobject.isZero())
365
16.7k
    return true;
366
367
53.7k
  if (!CanPlaceBaseSubobjectAtOffset(Info, Offset))
368
174
    return false;
369
370
  // We are able to place the base at this offset. Make sure to update the
371
  // empty base subobject map.
372
53.5k
  UpdateEmptyBaseSubobjects(Info, Offset, Info->Class->isEmpty());
373
53.5k
  return true;
374
53.7k
}
375
376
bool
377
EmptySubobjectMap::CanPlaceFieldSubobjectAtOffset(const CXXRecordDecl *RD,
378
                                                  const CXXRecordDecl *Class,
379
78.3k
                                                  CharUnits Offset) const {
380
  // We don't have to keep looking past the maximum offset that's known to
381
  // contain an empty class.
382
78.3k
  if (!AnyEmptySubobjectsBeyondOffset(Offset))
383
1.41k
    return true;
384
385
76.8k
  if (!CanPlaceSubobjectAtOffset(RD, Offset))
386
77
    return false;
387
388
76.8k
  const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
389
390
  // Traverse all non-virtual bases.
391
76.8k
  for (const CXXBaseSpecifier &Base : RD->bases()) {
392
17.4k
    if (Base.isVirtual())
393
46
      continue;
394
395
17.4k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
396
397
17.4k
    CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(BaseDecl);
398
17.4k
    if (!CanPlaceFieldSubobjectAtOffset(BaseDecl, Class, BaseOffset))
399
34
      return false;
400
17.4k
  }
401
402
76.7k
  if (RD == Class) {
403
    // This is the most derived class, traverse virtual bases as well.
404
60.7k
    for (const CXXBaseSpecifier &Base : RD->vbases()) {
405
46
      const CXXRecordDecl *VBaseDecl = Base.getType()->getAsCXXRecordDecl();
406
407
46
      CharUnits VBaseOffset = Offset + Layout.getVBaseClassOffset(VBaseDecl);
408
46
      if (!CanPlaceFieldSubobjectAtOffset(VBaseDecl, Class, VBaseOffset))
409
1
        return false;
410
46
    }
411
60.7k
  }
412
413
  // Traverse all member variables.
414
76.7k
  unsigned FieldNo = 0;
415
76.7k
  for (CXXRecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
416
231k
       I != E; 
++I, ++FieldNo154k
) {
417
154k
    if (I->isBitField())
418
20.9k
      continue;
419
420
133k
    CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
421
422
133k
    if (!CanPlaceFieldSubobjectAtOffset(*I, FieldOffset))
423
10
      return false;
424
133k
  }
425
426
76.7k
  return true;
427
76.7k
}
428
429
bool
430
EmptySubobjectMap::CanPlaceFieldSubobjectAtOffset(const FieldDecl *FD,
431
539k
                                                  CharUnits Offset) const {
432
  // We don't have to keep looking past the maximum offset that's known to
433
  // contain an empty class.
434
539k
  if (!AnyEmptySubobjectsBeyondOffset(Offset))
435
337k
    return true;
436
437
201k
  QualType T = FD->getType();
438
201k
  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
439
60.4k
    return CanPlaceFieldSubobjectAtOffset(RD, RD, Offset);
440
441
  // If we have an array type we need to look at every element.
442
141k
  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(T)) {
443
15.0k
    QualType ElemTy = Context.getBaseElementType(AT);
444
15.0k
    const RecordType *RT = ElemTy->getAs<RecordType>();
445
15.0k
    if (!RT)
446
13.6k
      return true;
447
448
1.35k
    const CXXRecordDecl *RD = RT->getAsCXXRecordDecl();
449
1.35k
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
450
451
1.35k
    uint64_t NumElements = Context.getConstantArrayElementCount(AT);
452
1.35k
    CharUnits ElementOffset = Offset;
453
1.67k
    for (uint64_t I = 0; I != NumElements; 
++I321
) {
454
      // We don't have to keep looking past the maximum offset that's known to
455
      // contain an empty class.
456
601
      if (!AnyEmptySubobjectsBeyondOffset(ElementOffset))
457
274
        return true;
458
459
327
      if (!CanPlaceFieldSubobjectAtOffset(RD, RD, ElementOffset))
460
6
        return false;
461
462
321
      ElementOffset += Layout.getSize();
463
321
    }
464
1.35k
  }
465
466
127k
  return true;
467
141k
}
468
469
bool
470
EmptySubobjectMap::CanPlaceFieldAtOffset(const FieldDecl *FD,
471
390k
                                         CharUnits Offset) {
472
390k
  if (!CanPlaceFieldSubobjectAtOffset(FD, Offset))
473
75
    return false;
474
475
  // We are able to place the member variable at this offset.
476
  // Make sure to update the empty field subobject map.
477
390k
  UpdateEmptyFieldSubobjects(FD, Offset, FD->hasAttr<NoUniqueAddressAttr>());
478
390k
  return true;
479
390k
}
480
481
void EmptySubobjectMap::UpdateEmptyFieldSubobjects(
482
    const CXXRecordDecl *RD, const CXXRecordDecl *Class, CharUnits Offset,
483
103k
    bool PlacingOverlappingField) {
484
  // We know that the only empty subobjects that can conflict with empty
485
  // field subobjects are subobjects of empty bases and potentially-overlapping
486
  // fields that can be placed at offset zero. Because of this, we only need to
487
  // keep track of empty field subobjects with offsets less than the size of
488
  // the largest empty subobject for our class.
489
  //
490
  // (Proof: we will only consider placing a subobject at offset zero or at
491
  // >= the current dsize. The only cases where the earlier subobject can be
492
  // placed beyond the end of dsize is if it's an empty base or a
493
  // potentially-overlapping field.)
494
103k
  if (!PlacingOverlappingField && 
Offset >= SizeOfLargestEmptySubobject102k
)
495
59.9k
    return;
496
497
43.0k
  AddSubobjectAtOffset(RD, Offset);
498
499
43.0k
  const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
500
501
  // Traverse all non-virtual bases.
502
43.0k
  for (const CXXBaseSpecifier &Base : RD->bases()) {
503
14.5k
    if (Base.isVirtual())
504
44
      continue;
505
506
14.5k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
507
508
14.5k
    CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(BaseDecl);
509
14.5k
    UpdateEmptyFieldSubobjects(BaseDecl, Class, BaseOffset,
510
14.5k
                               PlacingOverlappingField);
511
14.5k
  }
512
513
43.0k
  if (RD == Class) {
514
    // This is the most derived class, traverse virtual bases as well.
515
28.9k
    for (const CXXBaseSpecifier &Base : RD->vbases()) {
516
44
      const CXXRecordDecl *VBaseDecl = Base.getType()->getAsCXXRecordDecl();
517
518
44
      CharUnits VBaseOffset = Offset + Layout.getVBaseClassOffset(VBaseDecl);
519
44
      UpdateEmptyFieldSubobjects(VBaseDecl, Class, VBaseOffset,
520
44
                                 PlacingOverlappingField);
521
44
    }
522
28.9k
  }
523
524
  // Traverse all member variables.
525
43.0k
  unsigned FieldNo = 0;
526
43.0k
  for (CXXRecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
527
100k
       I != E; 
++I, ++FieldNo57.4k
) {
528
57.4k
    if (I->isBitField())
529
9.08k
      continue;
530
531
48.4k
    CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
532
533
48.4k
    UpdateEmptyFieldSubobjects(*I, FieldOffset, PlacingOverlappingField);
534
48.4k
  }
535
43.0k
}
536
537
void EmptySubobjectMap::UpdateEmptyFieldSubobjects(
538
453k
    const FieldDecl *FD, CharUnits Offset, bool PlacingOverlappingField) {
539
453k
  QualType T = FD->getType();
540
453k
  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
541
88.3k
    UpdateEmptyFieldSubobjects(RD, RD, Offset, PlacingOverlappingField);
542
88.3k
    return;
543
88.3k
  }
544
545
  // If we have an array type we need to update every element.
546
365k
  if (const ConstantArrayType *AT = Context.getAsConstantArrayType(T)) {
547
37.6k
    QualType ElemTy = Context.getBaseElementType(AT);
548
37.6k
    const RecordType *RT = ElemTy->getAs<RecordType>();
549
37.6k
    if (!RT)
550
35.3k
      return;
551
552
2.28k
    const CXXRecordDecl *RD = RT->getAsCXXRecordDecl();
553
2.28k
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
554
555
2.28k
    uint64_t NumElements = Context.getConstantArrayElementCount(AT);
556
2.28k
    CharUnits ElementOffset = Offset;
557
558
2.41k
    for (uint64_t I = 0; I != NumElements; 
++I122
) {
559
      // We know that the only empty subobjects that can conflict with empty
560
      // field subobjects are subobjects of empty bases that can be placed at
561
      // offset zero. Because of this, we only need to keep track of empty field
562
      // subobjects with offsets less than the size of the largest empty
563
      // subobject for our class.
564
1.34k
      if (!PlacingOverlappingField &&
565
1.34k
          
ElementOffset >= SizeOfLargestEmptySubobject1.32k
)
566
1.22k
        return;
567
568
122
      UpdateEmptyFieldSubobjects(RD, RD, ElementOffset,
569
122
                                 PlacingOverlappingField);
570
122
      ElementOffset += Layout.getSize();
571
122
    }
572
2.28k
  }
573
365k
}
574
575
typedef llvm::SmallPtrSet<const CXXRecordDecl*, 4> ClassSetTy;
576
577
class ItaniumRecordLayoutBuilder {
578
protected:
579
  // FIXME: Remove this and make the appropriate fields public.
580
  friend class clang::ASTContext;
581
582
  const ASTContext &Context;
583
584
  EmptySubobjectMap *EmptySubobjects;
585
586
  /// Size - The current size of the record layout.
587
  uint64_t Size;
588
589
  /// Alignment - The current alignment of the record layout.
590
  CharUnits Alignment;
591
592
  /// PreferredAlignment - The preferred alignment of the record layout.
593
  CharUnits PreferredAlignment;
594
595
  /// The alignment if attribute packed is not used.
596
  CharUnits UnpackedAlignment;
597
598
  /// \brief The maximum of the alignments of top-level members.
599
  CharUnits UnadjustedAlignment;
600
601
  SmallVector<uint64_t, 16> FieldOffsets;
602
603
  /// Whether the external AST source has provided a layout for this
604
  /// record.
605
  unsigned UseExternalLayout : 1;
606
607
  /// Whether we need to infer alignment, even when we have an
608
  /// externally-provided layout.
609
  unsigned InferAlignment : 1;
610
611
  /// Packed - Whether the record is packed or not.
612
  unsigned Packed : 1;
613
614
  unsigned IsUnion : 1;
615
616
  unsigned IsMac68kAlign : 1;
617
618
  unsigned IsNaturalAlign : 1;
619
620
  unsigned IsMsStruct : 1;
621
622
  /// UnfilledBitsInLastUnit - If the last field laid out was a bitfield,
623
  /// this contains the number of bits in the last unit that can be used for
624
  /// an adjacent bitfield if necessary.  The unit in question is usually
625
  /// a byte, but larger units are used if IsMsStruct.
626
  unsigned char UnfilledBitsInLastUnit;
627
628
  /// LastBitfieldStorageUnitSize - If IsMsStruct, represents the size of the
629
  /// storage unit of the previous field if it was a bitfield.
630
  unsigned char LastBitfieldStorageUnitSize;
631
632
  /// MaxFieldAlignment - The maximum allowed field alignment. This is set by
633
  /// #pragma pack.
634
  CharUnits MaxFieldAlignment;
635
636
  /// DataSize - The data size of the record being laid out.
637
  uint64_t DataSize;
638
639
  CharUnits NonVirtualSize;
640
  CharUnits NonVirtualAlignment;
641
  CharUnits PreferredNVAlignment;
642
643
  /// If we've laid out a field but not included its tail padding in Size yet,
644
  /// this is the size up to the end of that field.
645
  CharUnits PaddedFieldSize;
646
647
  /// PrimaryBase - the primary base class (if one exists) of the class
648
  /// we're laying out.
649
  const CXXRecordDecl *PrimaryBase;
650
651
  /// PrimaryBaseIsVirtual - Whether the primary base of the class we're laying
652
  /// out is virtual.
653
  bool PrimaryBaseIsVirtual;
654
655
  /// HasOwnVFPtr - Whether the class provides its own vtable/vftbl
656
  /// pointer, as opposed to inheriting one from a primary base class.
657
  bool HasOwnVFPtr;
658
659
  /// the flag of field offset changing due to packed attribute.
660
  bool HasPackedField;
661
662
  /// HandledFirstNonOverlappingEmptyField - An auxiliary field used for AIX.
663
  /// When there are OverlappingEmptyFields existing in the aggregate, the
664
  /// flag shows if the following first non-empty or empty-but-non-overlapping
665
  /// field has been handled, if any.
666
  bool HandledFirstNonOverlappingEmptyField;
667
668
  typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsetsMapTy;
669
670
  /// Bases - base classes and their offsets in the record.
671
  BaseOffsetsMapTy Bases;
672
673
  // VBases - virtual base classes and their offsets in the record.
674
  ASTRecordLayout::VBaseOffsetsMapTy VBases;
675
676
  /// IndirectPrimaryBases - Virtual base classes, direct or indirect, that are
677
  /// primary base classes for some other direct or indirect base class.
678
  CXXIndirectPrimaryBaseSet IndirectPrimaryBases;
679
680
  /// FirstNearlyEmptyVBase - The first nearly empty virtual base class in
681
  /// inheritance graph order. Used for determining the primary base class.
682
  const CXXRecordDecl *FirstNearlyEmptyVBase;
683
684
  /// VisitedVirtualBases - A set of all the visited virtual bases, used to
685
  /// avoid visiting virtual bases more than once.
686
  llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBases;
687
688
  /// Valid if UseExternalLayout is true.
689
  ExternalLayout External;
690
691
  ItaniumRecordLayoutBuilder(const ASTContext &Context,
692
                             EmptySubobjectMap *EmptySubobjects)
693
      : Context(Context), EmptySubobjects(EmptySubobjects), Size(0),
694
        Alignment(CharUnits::One()), PreferredAlignment(CharUnits::One()),
695
        UnpackedAlignment(CharUnits::One()),
696
        UnadjustedAlignment(CharUnits::One()), UseExternalLayout(false),
697
        InferAlignment(false), Packed(false), IsUnion(false),
698
        IsMac68kAlign(false),
699
        IsNaturalAlign(!Context.getTargetInfo().getTriple().isOSAIX()),
700
        IsMsStruct(false), UnfilledBitsInLastUnit(0),
701
        LastBitfieldStorageUnitSize(0), MaxFieldAlignment(CharUnits::Zero()),
702
        DataSize(0), NonVirtualSize(CharUnits::Zero()),
703
        NonVirtualAlignment(CharUnits::One()),
704
        PreferredNVAlignment(CharUnits::One()),
705
        PaddedFieldSize(CharUnits::Zero()), PrimaryBase(nullptr),
706
        PrimaryBaseIsVirtual(false), HasOwnVFPtr(false), HasPackedField(false),
707
        HandledFirstNonOverlappingEmptyField(false),
708
413k
        FirstNearlyEmptyVBase(nullptr) {}
709
710
  void Layout(const RecordDecl *D);
711
  void Layout(const CXXRecordDecl *D);
712
  void Layout(const ObjCInterfaceDecl *D);
713
714
  void LayoutFields(const RecordDecl *D);
715
  void LayoutField(const FieldDecl *D, bool InsertExtraPadding);
716
  void LayoutWideBitField(uint64_t FieldSize, uint64_t StorageUnitSize,
717
                          bool FieldPacked, const FieldDecl *D);
718
  void LayoutBitField(const FieldDecl *D);
719
720
0
  TargetCXXABI getCXXABI() const {
721
0
    return Context.getTargetInfo().getCXXABI();
722
0
  }
723
724
  /// BaseSubobjectInfoAllocator - Allocator for BaseSubobjectInfo objects.
725
  llvm::SpecificBumpPtrAllocator<BaseSubobjectInfo> BaseSubobjectInfoAllocator;
726
727
  typedef llvm::DenseMap<const CXXRecordDecl *, BaseSubobjectInfo *>
728
    BaseSubobjectInfoMapTy;
729
730
  /// VirtualBaseInfo - Map from all the (direct or indirect) virtual bases
731
  /// of the class we're laying out to their base subobject info.
732
  BaseSubobjectInfoMapTy VirtualBaseInfo;
733
734
  /// NonVirtualBaseInfo - Map from all the direct non-virtual bases of the
735
  /// class we're laying out to their base subobject info.
736
  BaseSubobjectInfoMapTy NonVirtualBaseInfo;
737
738
  /// ComputeBaseSubobjectInfo - Compute the base subobject information for the
739
  /// bases of the given class.
740
  void ComputeBaseSubobjectInfo(const CXXRecordDecl *RD);
741
742
  /// ComputeBaseSubobjectInfo - Compute the base subobject information for a
743
  /// single class and all of its base classes.
744
  BaseSubobjectInfo *ComputeBaseSubobjectInfo(const CXXRecordDecl *RD,
745
                                              bool IsVirtual,
746
                                              BaseSubobjectInfo *Derived);
747
748
  /// DeterminePrimaryBase - Determine the primary base of the given class.
749
  void DeterminePrimaryBase(const CXXRecordDecl *RD);
750
751
  void SelectPrimaryVBase(const CXXRecordDecl *RD);
752
753
  void EnsureVTablePointerAlignment(CharUnits UnpackedBaseAlign);
754
755
  /// LayoutNonVirtualBases - Determines the primary base class (if any) and
756
  /// lays it out. Will then proceed to lay out all non-virtual base clasess.
757
  void LayoutNonVirtualBases(const CXXRecordDecl *RD);
758
759
  /// LayoutNonVirtualBase - Lays out a single non-virtual base.
760
  void LayoutNonVirtualBase(const BaseSubobjectInfo *Base);
761
762
  void AddPrimaryVirtualBaseOffsets(const BaseSubobjectInfo *Info,
763
                                    CharUnits Offset);
764
765
  /// LayoutVirtualBases - Lays out all the virtual bases.
766
  void LayoutVirtualBases(const CXXRecordDecl *RD,
767
                          const CXXRecordDecl *MostDerivedClass);
768
769
  /// LayoutVirtualBase - Lays out a single virtual base.
770
  void LayoutVirtualBase(const BaseSubobjectInfo *Base);
771
772
  /// LayoutBase - Will lay out a base and return the offset where it was
773
  /// placed, in chars.
774
  CharUnits LayoutBase(const BaseSubobjectInfo *Base);
775
776
  /// InitializeLayout - Initialize record layout for the given record decl.
777
  void InitializeLayout(const Decl *D);
778
779
  /// FinishLayout - Finalize record layout. Adjust record size based on the
780
  /// alignment.
781
  void FinishLayout(const NamedDecl *D);
782
783
  void UpdateAlignment(CharUnits NewAlignment, CharUnits UnpackedNewAlignment,
784
                       CharUnits PreferredAlignment);
785
24.0k
  void UpdateAlignment(CharUnits NewAlignment, CharUnits UnpackedNewAlignment) {
786
24.0k
    UpdateAlignment(NewAlignment, UnpackedNewAlignment, NewAlignment);
787
24.0k
  }
788
7.38k
  void UpdateAlignment(CharUnits NewAlignment) {
789
7.38k
    UpdateAlignment(NewAlignment, NewAlignment, NewAlignment);
790
7.38k
  }
791
792
  /// Retrieve the externally-supplied field offset for the given
793
  /// field.
794
  ///
795
  /// \param Field The field whose offset is being queried.
796
  /// \param ComputedOffset The offset that we've computed for this field.
797
  uint64_t updateExternalFieldOffset(const FieldDecl *Field,
798
                                     uint64_t ComputedOffset);
799
800
  void CheckFieldPadding(uint64_t Offset, uint64_t UnpaddedOffset,
801
                          uint64_t UnpackedOffset, unsigned UnpackedAlign,
802
                          bool isPacked, const FieldDecl *D);
803
804
  DiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID);
805
806
762k
  CharUnits getSize() const {
807
762k
    assert(Size % Context.getCharWidth() == 0);
808
0
    return Context.toCharUnitsFromBits(Size);
809
762k
  }
810
3.53M
  uint64_t getSizeInBits() const { return Size; }
811
812
169k
  void setSize(CharUnits NewSize) { Size = Context.toBits(NewSize); }
813
1.69M
  void setSize(uint64_t NewSize) { Size = NewSize; }
814
815
0
  CharUnits getAligment() const { return Alignment; }
816
817
1.02M
  CharUnits getDataSize() const {
818
1.02M
    assert(DataSize % Context.getCharWidth() == 0);
819
0
    return Context.toCharUnitsFromBits(DataSize);
820
1.02M
  }
821
1.80M
  uint64_t getDataSizeInBits() const { return DataSize; }
822
823
835k
  void setDataSize(CharUnits NewSize) { DataSize = Context.toBits(NewSize); }
824
71.3k
  void setDataSize(uint64_t NewSize) { DataSize = NewSize; }
825
826
  ItaniumRecordLayoutBuilder(const ItaniumRecordLayoutBuilder &) = delete;
827
  void operator=(const ItaniumRecordLayoutBuilder &) = delete;
828
};
829
} // end anonymous namespace
830
831
1.89k
void ItaniumRecordLayoutBuilder::SelectPrimaryVBase(const CXXRecordDecl *RD) {
832
1.89k
  for (const auto &I : RD->bases()) {
833
1.27k
    assert(!I.getType()->isDependentType() &&
834
1.27k
           "Cannot layout class with dependent bases.");
835
836
0
    const CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
837
838
    // Check if this is a nearly empty virtual base.
839
1.27k
    if (I.isVirtual() && 
Context.isNearlyEmpty(Base)904
) {
840
      // If it's not an indirect primary base, then we've found our primary
841
      // base.
842
233
      if (!IndirectPrimaryBases.count(Base)) {
843
230
        PrimaryBase = Base;
844
230
        PrimaryBaseIsVirtual = true;
845
230
        return;
846
230
      }
847
848
      // Is this the first nearly empty virtual base?
849
3
      if (!FirstNearlyEmptyVBase)
850
3
        FirstNearlyEmptyVBase = Base;
851
3
    }
852
853
1.04k
    SelectPrimaryVBase(Base);
854
1.04k
    if (PrimaryBase)
855
12
      return;
856
1.04k
  }
857
1.89k
}
858
859
/// DeterminePrimaryBase - Determine the primary base of the given class.
860
294k
void ItaniumRecordLayoutBuilder::DeterminePrimaryBase(const CXXRecordDecl *RD) {
861
  // If the class isn't dynamic, it won't have a primary base.
862
294k
  if (!RD->isDynamicClass())
863
277k
    return;
864
865
  // Compute all the primary virtual bases for all of our direct and
866
  // indirect bases, and record all their primary virtual base classes.
867
17.3k
  RD->getIndirectPrimaryBases(IndirectPrimaryBases);
868
869
  // If the record has a dynamic base class, attempt to choose a primary base
870
  // class. It is the first (in direct base class order) non-virtual dynamic
871
  // base class, if one exists.
872
17.3k
  for (const auto &I : RD->bases()) {
873
    // Ignore virtual bases.
874
12.2k
    if (I.isVirtual())
875
931
      continue;
876
877
11.3k
    const CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
878
879
11.3k
    if (Base->isDynamicClass()) {
880
      // We found it.
881
11.1k
      PrimaryBase = Base;
882
11.1k
      PrimaryBaseIsVirtual = false;
883
11.1k
      return;
884
11.1k
    }
885
11.3k
  }
886
887
  // Under the Itanium ABI, if there is no non-virtual primary base class,
888
  // try to compute the primary virtual base.  The primary virtual base is
889
  // the first nearly empty virtual base that is not an indirect primary
890
  // virtual base class, if one exists.
891
6.22k
  if (RD->getNumVBases() != 0) {
892
846
    SelectPrimaryVBase(RD);
893
846
    if (PrimaryBase)
894
230
      return;
895
846
  }
896
897
  // Otherwise, it is the first indirect primary base class, if one exists.
898
5.99k
  if (FirstNearlyEmptyVBase) {
899
2
    PrimaryBase = FirstNearlyEmptyVBase;
900
2
    PrimaryBaseIsVirtual = true;
901
2
    return;
902
2
  }
903
904
5.99k
  assert(!PrimaryBase && "Should not get here with a primary base!");
905
5.99k
}
906
907
BaseSubobjectInfo *ItaniumRecordLayoutBuilder::ComputeBaseSubobjectInfo(
908
1.12M
    const CXXRecordDecl *RD, bool IsVirtual, BaseSubobjectInfo *Derived) {
909
1.12M
  BaseSubobjectInfo *Info;
910
911
1.12M
  if (IsVirtual) {
912
    // Check if we already have info about this virtual base.
913
1.87k
    BaseSubobjectInfo *&InfoSlot = VirtualBaseInfo[RD];
914
1.87k
    if (InfoSlot) {
915
293
      assert(InfoSlot->Class == RD && "Wrong class for virtual base info!");
916
0
      return InfoSlot;
917
293
    }
918
919
    // We don't, create it.
920
1.58k
    InfoSlot = new (BaseSubobjectInfoAllocator.Allocate()) BaseSubobjectInfo;
921
1.58k
    Info = InfoSlot;
922
1.12M
  } else {
923
1.12M
    Info = new (BaseSubobjectInfoAllocator.Allocate()) BaseSubobjectInfo;
924
1.12M
  }
925
926
1.12M
  Info->Class = RD;
927
1.12M
  Info->IsVirtual = IsVirtual;
928
1.12M
  Info->Derived = nullptr;
929
1.12M
  Info->PrimaryVirtualBaseInfo = nullptr;
930
931
1.12M
  const CXXRecordDecl *PrimaryVirtualBase = nullptr;
932
1.12M
  BaseSubobjectInfo *PrimaryVirtualBaseInfo = nullptr;
933
934
  // Check if this base has a primary virtual base.
935
1.12M
  if (RD->getNumVBases()) {
936
881
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
937
881
    if (Layout.isPrimaryBaseVirtual()) {
938
      // This base does have a primary virtual base.
939
203
      PrimaryVirtualBase = Layout.getPrimaryBase();
940
203
      assert(PrimaryVirtualBase && "Didn't have a primary virtual base!");
941
942
      // Now check if we have base subobject info about this primary base.
943
0
      PrimaryVirtualBaseInfo = VirtualBaseInfo.lookup(PrimaryVirtualBase);
944
945
203
      if (PrimaryVirtualBaseInfo) {
946
68
        if (PrimaryVirtualBaseInfo->Derived) {
947
          // We did have info about this primary base, and it turns out that it
948
          // has already been claimed as a primary virtual base for another
949
          // base.
950
34
          PrimaryVirtualBase = nullptr;
951
34
        } else {
952
          // We can claim this base as our primary base.
953
34
          Info->PrimaryVirtualBaseInfo = PrimaryVirtualBaseInfo;
954
34
          PrimaryVirtualBaseInfo->Derived = Info;
955
34
        }
956
68
      }
957
203
    }
958
881
  }
959
960
  // Now go through all direct bases.
961
1.05M
  for (const auto &I : RD->bases()) {
962
1.05M
    bool IsVirtual = I.isVirtual();
963
964
1.05M
    const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
965
966
1.05M
    Info->Bases.push_back(ComputeBaseSubobjectInfo(BaseDecl, IsVirtual, Info));
967
1.05M
  }
968
969
1.12M
  if (PrimaryVirtualBase && 
!PrimaryVirtualBaseInfo169
) {
970
    // Traversing the bases must have created the base info for our primary
971
    // virtual base.
972
135
    PrimaryVirtualBaseInfo = VirtualBaseInfo.lookup(PrimaryVirtualBase);
973
135
    assert(PrimaryVirtualBaseInfo &&
974
135
           "Did not create a primary virtual base!");
975
976
    // Claim the primary virtual base as our primary virtual base.
977
0
    Info->PrimaryVirtualBaseInfo = PrimaryVirtualBaseInfo;
978
135
    PrimaryVirtualBaseInfo->Derived = Info;
979
135
  }
980
981
0
  return Info;
982
1.12M
}
983
984
void ItaniumRecordLayoutBuilder::ComputeBaseSubobjectInfo(
985
294k
    const CXXRecordDecl *RD) {
986
294k
  for (const auto &I : RD->bases()) {
987
69.9k
    bool IsVirtual = I.isVirtual();
988
989
69.9k
    const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
990
991
    // Compute the base subobject info for this base.
992
69.9k
    BaseSubobjectInfo *Info = ComputeBaseSubobjectInfo(BaseDecl, IsVirtual,
993
69.9k
                                                       nullptr);
994
995
69.9k
    if (IsVirtual) {
996
      // ComputeBaseInfo has already added this base for us.
997
997
      assert(VirtualBaseInfo.count(BaseDecl) &&
998
997
             "Did not add virtual base!");
999
68.9k
    } else {
1000
      // Add the base info to the map of non-virtual bases.
1001
68.9k
      assert(!NonVirtualBaseInfo.count(BaseDecl) &&
1002
68.9k
             "Non-virtual base already exists!");
1003
0
      NonVirtualBaseInfo.insert(std::make_pair(BaseDecl, Info));
1004
68.9k
    }
1005
69.9k
  }
1006
294k
}
1007
1008
void ItaniumRecordLayoutBuilder::EnsureVTablePointerAlignment(
1009
5.99k
    CharUnits UnpackedBaseAlign) {
1010
5.99k
  CharUnits BaseAlign = Packed ? 
CharUnits::One()2
:
UnpackedBaseAlign5.98k
;
1011
1012
  // The maximum field alignment overrides base align.
1013
5.99k
  if (!MaxFieldAlignment.isZero()) {
1014
5
    BaseAlign = std::min(BaseAlign, MaxFieldAlignment);
1015
5
    UnpackedBaseAlign = std::min(UnpackedBaseAlign, MaxFieldAlignment);
1016
5
  }
1017
1018
  // Round up the current record size to pointer alignment.
1019
5.99k
  setSize(getSize().alignTo(BaseAlign));
1020
1021
  // Update the alignment.
1022
5.99k
  UpdateAlignment(BaseAlign, UnpackedBaseAlign, BaseAlign);
1023
5.99k
}
1024
1025
void ItaniumRecordLayoutBuilder::LayoutNonVirtualBases(
1026
294k
    const CXXRecordDecl *RD) {
1027
  // Then, determine the primary base class.
1028
294k
  DeterminePrimaryBase(RD);
1029
1030
  // Compute base subobject info.
1031
294k
  ComputeBaseSubobjectInfo(RD);
1032
1033
  // If we have a primary base class, lay it out.
1034
294k
  if (PrimaryBase) {
1035
11.3k
    if (PrimaryBaseIsVirtual) {
1036
      // If the primary virtual base was a primary virtual base of some other
1037
      // base class we'll have to steal it.
1038
232
      BaseSubobjectInfo *PrimaryBaseInfo = VirtualBaseInfo.lookup(PrimaryBase);
1039
232
      PrimaryBaseInfo->Derived = nullptr;
1040
1041
      // We have a virtual primary base, insert it as an indirect primary base.
1042
232
      IndirectPrimaryBases.insert(PrimaryBase);
1043
1044
232
      assert(!VisitedVirtualBases.count(PrimaryBase) &&
1045
232
             "vbase already visited!");
1046
0
      VisitedVirtualBases.insert(PrimaryBase);
1047
1048
232
      LayoutVirtualBase(PrimaryBaseInfo);
1049
11.1k
    } else {
1050
11.1k
      BaseSubobjectInfo *PrimaryBaseInfo =
1051
11.1k
        NonVirtualBaseInfo.lookup(PrimaryBase);
1052
11.1k
      assert(PrimaryBaseInfo &&
1053
11.1k
             "Did not find base info for non-virtual primary base!");
1054
1055
0
      LayoutNonVirtualBase(PrimaryBaseInfo);
1056
11.1k
    }
1057
1058
  // If this class needs a vtable/vf-table and didn't get one from a
1059
  // primary base, add it in now.
1060
283k
  } else if (RD->isDynamicClass()) {
1061
5.99k
    assert(DataSize == 0 && "Vtable pointer must be at offset zero!");
1062
0
    CharUnits PtrWidth =
1063
5.99k
      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
1064
5.99k
    CharUnits PtrAlign =
1065
5.99k
      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerAlign(0));
1066
5.99k
    EnsureVTablePointerAlignment(PtrAlign);
1067
5.99k
    HasOwnVFPtr = true;
1068
1069
5.99k
    assert(!IsUnion && "Unions cannot be dynamic classes.");
1070
0
    HandledFirstNonOverlappingEmptyField = true;
1071
1072
5.99k
    setSize(getSize() + PtrWidth);
1073
5.99k
    setDataSize(getSize());
1074
5.99k
  }
1075
1076
  // Now lay out the non-virtual bases.
1077
69.9k
  for (const auto &I : RD->bases()) {
1078
1079
    // Ignore virtual bases.
1080
69.9k
    if (I.isVirtual())
1081
997
      continue;
1082
1083
68.9k
    const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
1084
1085
    // Skip the primary base, because we've already laid it out.  The
1086
    // !PrimaryBaseIsVirtual check is required because we might have a
1087
    // non-virtual base of the same type as a primary virtual base.
1088
68.9k
    if (BaseDecl == PrimaryBase && 
!PrimaryBaseIsVirtual11.1k
)
1089
11.1k
      continue;
1090
1091
    // Lay out the base.
1092
57.8k
    BaseSubobjectInfo *BaseInfo = NonVirtualBaseInfo.lookup(BaseDecl);
1093
57.8k
    assert(BaseInfo && "Did not find base info for non-virtual base!");
1094
1095
0
    LayoutNonVirtualBase(BaseInfo);
1096
57.8k
  }
1097
294k
}
1098
1099
void ItaniumRecordLayoutBuilder::LayoutNonVirtualBase(
1100
68.9k
    const BaseSubobjectInfo *Base) {
1101
  // Layout the base.
1102
68.9k
  CharUnits Offset = LayoutBase(Base);
1103
1104
  // Add its base class offset.
1105
68.9k
  assert(!Bases.count(Base->Class) && "base offset already exists!");
1106
0
  Bases.insert(std::make_pair(Base->Class, Offset));
1107
1108
68.9k
  AddPrimaryVirtualBaseOffsets(Base, Offset);
1109
68.9k
}
1110
1111
void ItaniumRecordLayoutBuilder::AddPrimaryVirtualBaseOffsets(
1112
70.7k
    const BaseSubobjectInfo *Info, CharUnits Offset) {
1113
  // This base isn't interesting, it has no virtual bases.
1114
70.7k
  if (!Info->Class->getNumVBases())
1115
69.8k
    return;
1116
1117
  // First, check if we have a virtual primary base to add offsets for.
1118
881
  if (Info->PrimaryVirtualBaseInfo) {
1119
169
    assert(Info->PrimaryVirtualBaseInfo->IsVirtual &&
1120
169
           "Primary virtual base is not virtual!");
1121
169
    if (Info->PrimaryVirtualBaseInfo->Derived == Info) {
1122
      // Add the offset.
1123
166
      assert(!VBases.count(Info->PrimaryVirtualBaseInfo->Class) &&
1124
166
             "primary vbase offset already exists!");
1125
0
      VBases.insert(std::make_pair(Info->PrimaryVirtualBaseInfo->Class,
1126
166
                                   ASTRecordLayout::VBaseInfo(Offset, false)));
1127
1128
      // Traverse the primary virtual base.
1129
166
      AddPrimaryVirtualBaseOffsets(Info->PrimaryVirtualBaseInfo, Offset);
1130
166
    }
1131
169
  }
1132
1133
  // Now go through all direct non-virtual bases.
1134
0
  const ASTRecordLayout &Layout = Context.getASTRecordLayout(Info->Class);
1135
1.15k
  for (const BaseSubobjectInfo *Base : Info->Bases) {
1136
1.15k
    if (Base->IsVirtual)
1137
880
      continue;
1138
1139
278
    CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base->Class);
1140
278
    AddPrimaryVirtualBaseOffsets(Base, BaseOffset);
1141
278
  }
1142
881
}
1143
1144
void ItaniumRecordLayoutBuilder::LayoutVirtualBases(
1145
295k
    const CXXRecordDecl *RD, const CXXRecordDecl *MostDerivedClass) {
1146
295k
  const CXXRecordDecl *PrimaryBase;
1147
295k
  bool PrimaryBaseIsVirtual;
1148
1149
295k
  if (MostDerivedClass == RD) {
1150
294k
    PrimaryBase = this->PrimaryBase;
1151
294k
    PrimaryBaseIsVirtual = this->PrimaryBaseIsVirtual;
1152
294k
  } else {
1153
885
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1154
885
    PrimaryBase = Layout.getPrimaryBase();
1155
885
    PrimaryBaseIsVirtual = Layout.isPrimaryBaseVirtual();
1156
885
  }
1157
1158
295k
  for (const CXXBaseSpecifier &Base : RD->bases()) {
1159
71.0k
    assert(!Base.getType()->isDependentType() &&
1160
71.0k
           "Cannot layout class with dependent bases.");
1161
1162
0
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
1163
1164
71.0k
    if (Base.isVirtual()) {
1165
1.88k
      if (PrimaryBase != BaseDecl || 
!PrimaryBaseIsVirtual413
) {
1166
1.46k
        bool IndirectPrimaryBase = IndirectPrimaryBases.count(BaseDecl);
1167
1168
        // Only lay out the virtual base if it's not an indirect primary base.
1169
1.46k
        if (!IndirectPrimaryBase) {
1170
          // Only visit virtual bases once.
1171
1.41k
          if (!VisitedVirtualBases.insert(BaseDecl).second)
1172
231
            continue;
1173
1174
1.18k
          const BaseSubobjectInfo *BaseInfo = VirtualBaseInfo.lookup(BaseDecl);
1175
1.18k
          assert(BaseInfo && "Did not find virtual base info!");
1176
0
          LayoutVirtualBase(BaseInfo);
1177
1.18k
        }
1178
1.46k
      }
1179
1.88k
    }
1180
1181
70.8k
    if (!BaseDecl->getNumVBases()) {
1182
      // This base isn't interesting since it doesn't have any virtual bases.
1183
69.9k
      continue;
1184
69.9k
    }
1185
1186
885
    LayoutVirtualBases(BaseDecl, MostDerivedClass);
1187
885
  }
1188
295k
}
1189
1190
void ItaniumRecordLayoutBuilder::LayoutVirtualBase(
1191
1.41k
    const BaseSubobjectInfo *Base) {
1192
1.41k
  assert(!Base->Derived && "Trying to lay out a primary virtual base!");
1193
1194
  // Layout the base.
1195
0
  CharUnits Offset = LayoutBase(Base);
1196
1197
  // Add its base class offset.
1198
1.41k
  assert(!VBases.count(Base->Class) && "vbase offset already exists!");
1199
0
  VBases.insert(std::make_pair(Base->Class,
1200
1.41k
                       ASTRecordLayout::VBaseInfo(Offset, false)));
1201
1202
1.41k
  AddPrimaryVirtualBaseOffsets(Base, Offset);
1203
1.41k
}
1204
1205
CharUnits
1206
70.3k
ItaniumRecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) {
1207
70.3k
  assert(!IsUnion && "Unions cannot have base classes.");
1208
1209
0
  const ASTRecordLayout &Layout = Context.getASTRecordLayout(Base->Class);
1210
70.3k
  CharUnits Offset;
1211
1212
  // Query the external layout to see if it provides an offset.
1213
70.3k
  bool HasExternalLayout = false;
1214
70.3k
  if (UseExternalLayout) {
1215
14.5k
    if (Base->IsVirtual)
1216
22
      HasExternalLayout = External.getExternalVBaseOffset(Base->Class, Offset);
1217
14.5k
    else
1218
14.5k
      HasExternalLayout = External.getExternalNVBaseOffset(Base->Class, Offset);
1219
14.5k
  }
1220
1221
140k
  auto getBaseOrPreferredBaseAlignFromUnpacked = [&](CharUnits UnpackedAlign) {
1222
    // Clang <= 6 incorrectly applied the 'packed' attribute to base classes.
1223
    // Per GCC's documentation, it only applies to non-static data members.
1224
140k
    return (Packed && 
(134
(Context.getLangOpts().getClangABICompat() <=
1225
134
                        LangOptions::ClangABI::Ver6) ||
1226
134
                       
Context.getTargetInfo().getTriple().isPS()120
||
1227
134
                       
Context.getTargetInfo().getTriple().isOSAIX()92
))
1228
140k
               ? 
CharUnits::One()58
1229
140k
               : 
UnpackedAlign140k
;
1230
140k
  };
1231
1232
70.3k
  CharUnits UnpackedBaseAlign = Layout.getNonVirtualAlignment();
1233
70.3k
  CharUnits UnpackedPreferredBaseAlign = Layout.getPreferredNVAlignment();
1234
70.3k
  CharUnits BaseAlign =
1235
70.3k
      getBaseOrPreferredBaseAlignFromUnpacked(UnpackedBaseAlign);
1236
70.3k
  CharUnits PreferredBaseAlign =
1237
70.3k
      getBaseOrPreferredBaseAlignFromUnpacked(UnpackedPreferredBaseAlign);
1238
1239
70.3k
  const bool DefaultsToAIXPowerAlignment =
1240
70.3k
      Context.getTargetInfo().defaultsToAIXPowerAlignment();
1241
70.3k
  if (DefaultsToAIXPowerAlignment) {
1242
    // AIX `power` alignment does not apply the preferred alignment for
1243
    // non-union classes if the source of the alignment (the current base in
1244
    // this context) follows introduction of the first subobject with
1245
    // exclusively allocated space or zero-extent array.
1246
46
    if (!Base->Class->isEmpty() && 
!HandledFirstNonOverlappingEmptyField40
) {
1247
      // By handling a base class that is not empty, we're handling the
1248
      // "first (inherited) member".
1249
24
      HandledFirstNonOverlappingEmptyField = true;
1250
24
    } else 
if (22
!IsNaturalAlign22
) {
1251
20
      UnpackedPreferredBaseAlign = UnpackedBaseAlign;
1252
20
      PreferredBaseAlign = BaseAlign;
1253
20
    }
1254
46
  }
1255
1256
70.3k
  CharUnits UnpackedAlignTo = !DefaultsToAIXPowerAlignment
1257
70.3k
                                  ? 
UnpackedBaseAlign70.2k
1258
70.3k
                                  : 
UnpackedPreferredBaseAlign46
;
1259
  // If we have an empty base class, try to place it at offset 0.
1260
70.3k
  if (Base->Class->isEmpty() &&
1261
70.3k
      
(41.7k
!HasExternalLayout41.7k
||
Offset == CharUnits::Zero()9.48k
) &&
1262
70.3k
      
EmptySubobjects->CanPlaceBaseAtOffset(Base, CharUnits::Zero())41.7k
) {
1263
41.6k
    setSize(std::max(getSize(), Layout.getSize()));
1264
    // On PS4/PS5, don't update the alignment, to preserve compatibility.
1265
41.6k
    if (!Context.getTargetInfo().getTriple().isPS())
1266
41.6k
      UpdateAlignment(BaseAlign, UnpackedAlignTo, PreferredBaseAlign);
1267
1268
41.6k
    return CharUnits::Zero();
1269
41.6k
  }
1270
1271
  // The maximum field alignment overrides the base align/(AIX-only) preferred
1272
  // base align.
1273
28.6k
  if (!MaxFieldAlignment.isZero()) {
1274
41
    BaseAlign = std::min(BaseAlign, MaxFieldAlignment);
1275
41
    PreferredBaseAlign = std::min(PreferredBaseAlign, MaxFieldAlignment);
1276
41
    UnpackedAlignTo = std::min(UnpackedAlignTo, MaxFieldAlignment);
1277
41
  }
1278
1279
28.6k
  CharUnits AlignTo =
1280
28.6k
      !DefaultsToAIXPowerAlignment ? 
BaseAlign28.6k
:
PreferredBaseAlign40
;
1281
28.6k
  if (!HasExternalLayout) {
1282
    // Round up the current record size to the base's alignment boundary.
1283
23.5k
    Offset = getDataSize().alignTo(AlignTo);
1284
1285
    // Try to place the base.
1286
23.6k
    while (!EmptySubobjects->CanPlaceBaseAtOffset(Base, Offset))
1287
61
      Offset += AlignTo;
1288
23.5k
  } else {
1289
5.09k
    bool Allowed = EmptySubobjects->CanPlaceBaseAtOffset(Base, Offset);
1290
5.09k
    (void)Allowed;
1291
5.09k
    assert(Allowed && "Base subobject externally placed at overlapping offset");
1292
1293
5.09k
    if (InferAlignment && 
Offset < getDataSize().alignTo(AlignTo)682
) {
1294
      // The externally-supplied base offset is before the base offset we
1295
      // computed. Assume that the structure is packed.
1296
0
      Alignment = CharUnits::One();
1297
0
      InferAlignment = false;
1298
0
    }
1299
5.09k
  }
1300
1301
28.6k
  if (!Base->Class->isEmpty()) {
1302
    // Update the data size.
1303
28.5k
    setDataSize(Offset + Layout.getNonVirtualSize());
1304
1305
28.5k
    setSize(std::max(getSize(), getDataSize()));
1306
28.5k
  } else
1307
113
    setSize(std::max(getSize(), Offset + Layout.getSize()));
1308
1309
  // Remember max struct/class alignment.
1310
28.6k
  UpdateAlignment(BaseAlign, UnpackedAlignTo, PreferredBaseAlign);
1311
1312
28.6k
  return Offset;
1313
70.3k
}
1314
1315
413k
void ItaniumRecordLayoutBuilder::InitializeLayout(const Decl *D) {
1316
413k
  if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) {
1317
408k
    IsUnion = RD->isUnion();
1318
408k
    IsMsStruct = RD->isMsStruct(Context);
1319
408k
  }
1320
1321
413k
  Packed = D->hasAttr<PackedAttr>();
1322
1323
  // Honor the default struct packing maximum alignment flag.
1324
413k
  if (unsigned DefaultMaxFieldAlignment = Context.getLangOpts().PackStruct) {
1325
2
    MaxFieldAlignment = CharUnits::fromQuantity(DefaultMaxFieldAlignment);
1326
2
  }
1327
1328
  // mac68k alignment supersedes maximum field alignment and attribute aligned,
1329
  // and forces all structures to have 2-byte alignment. The IBM docs on it
1330
  // allude to additional (more complicated) semantics, especially with regard
1331
  // to bit-fields, but gcc appears not to follow that.
1332
413k
  if (D->hasAttr<AlignMac68kAttr>()) {
1333
12
    assert(
1334
12
        !D->hasAttr<AlignNaturalAttr>() &&
1335
12
        "Having both mac68k and natural alignment on a decl is not allowed.");
1336
0
    IsMac68kAlign = true;
1337
12
    MaxFieldAlignment = CharUnits::fromQuantity(2);
1338
12
    Alignment = CharUnits::fromQuantity(2);
1339
12
    PreferredAlignment = CharUnits::fromQuantity(2);
1340
413k
  } else {
1341
413k
    if (D->hasAttr<AlignNaturalAttr>())
1342
26
      IsNaturalAlign = true;
1343
1344
413k
    if (const MaxFieldAlignmentAttr *MFAA = D->getAttr<MaxFieldAlignmentAttr>())
1345
44.8k
      MaxFieldAlignment = Context.toCharUnitsFromBits(MFAA->getAlignment());
1346
1347
413k
    if (unsigned MaxAlign = D->getMaxAlignment())
1348
3.50k
      UpdateAlignment(Context.toCharUnitsFromBits(MaxAlign));
1349
413k
  }
1350
1351
0
  HandledFirstNonOverlappingEmptyField =
1352
413k
      !Context.getTargetInfo().defaultsToAIXPowerAlignment() || 
IsNaturalAlign397
;
1353
1354
  // If there is an external AST source, ask it for the various offsets.
1355
413k
  if (const RecordDecl *RD = dyn_cast<RecordDecl>(D))
1356
408k
    if (ExternalASTSource *Source = Context.getExternalSource()) {
1357
147k
      UseExternalLayout = Source->layoutRecordType(
1358
147k
          RD, External.Size, External.Align, External.FieldOffsets,
1359
147k
          External.BaseOffsets, External.VirtualBaseOffsets);
1360
1361
      // Update based on external alignment.
1362
147k
      if (UseExternalLayout) {
1363
30.2k
        if (External.Align > 0) {
1364
25.5k
          Alignment = Context.toCharUnitsFromBits(External.Align);
1365
25.5k
          PreferredAlignment = Context.toCharUnitsFromBits(External.Align);
1366
25.5k
        } else {
1367
          // The external source didn't have alignment information; infer it.
1368
4.69k
          InferAlignment = true;
1369
4.69k
        }
1370
30.2k
      }
1371
147k
    }
1372
413k
}
1373
1374
113k
void ItaniumRecordLayoutBuilder::Layout(const RecordDecl *D) {
1375
113k
  InitializeLayout(D);
1376
113k
  LayoutFields(D);
1377
1378
  // Finally, round the size of the total struct up to the alignment of the
1379
  // struct itself.
1380
113k
  FinishLayout(D);
1381
113k
}
1382
1383
294k
void ItaniumRecordLayoutBuilder::Layout(const CXXRecordDecl *RD) {
1384
294k
  InitializeLayout(RD);
1385
1386
  // Lay out the vtable and the non-virtual bases.
1387
294k
  LayoutNonVirtualBases(RD);
1388
1389
294k
  LayoutFields(RD);
1390
1391
294k
  NonVirtualSize = Context.toCharUnitsFromBits(
1392
294k
      llvm::alignTo(getSizeInBits(), Context.getTargetInfo().getCharAlign()));
1393
294k
  NonVirtualAlignment = Alignment;
1394
294k
  PreferredNVAlignment = PreferredAlignment;
1395
1396
  // Lay out the virtual bases and add the primary virtual base offsets.
1397
294k
  LayoutVirtualBases(RD, RD);
1398
1399
  // Finally, round the size of the total struct up to the alignment
1400
  // of the struct itself.
1401
294k
  FinishLayout(RD);
1402
1403
294k
#ifndef NDEBUG
1404
  // Check that we have base offsets for all bases.
1405
294k
  for (const CXXBaseSpecifier &Base : RD->bases()) {
1406
69.9k
    if (Base.isVirtual())
1407
997
      continue;
1408
1409
68.9k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
1410
1411
68.9k
    assert(Bases.count(BaseDecl) && "Did not find base offset!");
1412
68.9k
  }
1413
1414
  // And all virtual bases.
1415
294k
  for (const CXXBaseSpecifier &Base : RD->vbases()) {
1416
1.58k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
1417
1418
1.58k
    assert(VBases.count(BaseDecl) && "Did not find base offset!");
1419
1.58k
  }
1420
294k
#endif
1421
294k
}
1422
1423
5.09k
void ItaniumRecordLayoutBuilder::Layout(const ObjCInterfaceDecl *D) {
1424
5.09k
  if (ObjCInterfaceDecl *SD = D->getSuperClass()) {
1425
3.83k
    const ASTRecordLayout &SL = Context.getASTObjCInterfaceLayout(SD);
1426
1427
3.83k
    UpdateAlignment(SL.getAlignment());
1428
1429
    // We start laying out ivars not at the end of the superclass
1430
    // structure, but at the next byte following the last field.
1431
3.83k
    setDataSize(SL.getDataSize());
1432
3.83k
    setSize(getDataSize());
1433
3.83k
  }
1434
1435
5.09k
  InitializeLayout(D);
1436
  // Layout each ivar sequentially.
1437
11.7k
  for (const ObjCIvarDecl *IVD = D->all_declared_ivar_begin(); IVD;
1438
6.60k
       IVD = IVD->getNextIvar())
1439
6.60k
    LayoutField(IVD, false);
1440
1441
  // Finally, round the size of the total struct up to the alignment of the
1442
  // struct itself.
1443
5.09k
  FinishLayout(D);
1444
5.09k
}
1445
1446
408k
void ItaniumRecordLayoutBuilder::LayoutFields(const RecordDecl *D) {
1447
  // Layout each field, for now, just sequentially, respecting alignment.  In
1448
  // the future, this will need to be tweakable by targets.
1449
408k
  bool InsertExtraPadding = D->mayInsertExtraPadding(/*EmitRemark=*/true);
1450
408k
  bool HasFlexibleArrayMember = D->hasFlexibleArrayMember();
1451
1.26M
  for (auto I = D->field_begin(), End = D->field_end(); I != End; 
++I861k
) {
1452
861k
    auto Next(I);
1453
861k
    ++Next;
1454
861k
    LayoutField(*I,
1455
861k
                InsertExtraPadding && 
(42
Next != End42
||
!HasFlexibleArrayMember16
));
1456
861k
  }
1457
408k
}
1458
1459
// Rounds the specified size to have it a multiple of the char size.
1460
static uint64_t
1461
roundUpSizeToCharAlignment(uint64_t Size,
1462
141
                           const ASTContext &Context) {
1463
141
  uint64_t CharAlignment = Context.getTargetInfo().getCharAlign();
1464
141
  return llvm::alignTo(Size, CharAlignment);
1465
141
}
1466
1467
void ItaniumRecordLayoutBuilder::LayoutWideBitField(uint64_t FieldSize,
1468
                                                    uint64_t StorageUnitSize,
1469
                                                    bool FieldPacked,
1470
40
                                                    const FieldDecl *D) {
1471
40
  assert(Context.getLangOpts().CPlusPlus &&
1472
40
         "Can only have wide bit-fields in C++!");
1473
1474
  // Itanium C++ ABI 2.4:
1475
  //   If sizeof(T)*8 < n, let T' be the largest integral POD type with
1476
  //   sizeof(T')*8 <= n.
1477
1478
0
  QualType IntegralPODTypes[] = {
1479
40
    Context.UnsignedCharTy, Context.UnsignedShortTy, Context.UnsignedIntTy,
1480
40
    Context.UnsignedLongTy, Context.UnsignedLongLongTy
1481
40
  };
1482
1483
40
  QualType Type;
1484
166
  for (const QualType &QT : IntegralPODTypes) {
1485
166
    uint64_t Size = Context.getTypeSize(QT);
1486
1487
166
    if (Size > FieldSize)
1488
20
      break;
1489
1490
146
    Type = QT;
1491
146
  }
1492
40
  assert(!Type.isNull() && "Did not find a type!");
1493
1494
0
  CharUnits TypeAlign = Context.getTypeAlignInChars(Type);
1495
1496
  // We're not going to use any of the unfilled bits in the last byte.
1497
40
  UnfilledBitsInLastUnit = 0;
1498
40
  LastBitfieldStorageUnitSize = 0;
1499
1500
40
  uint64_t FieldOffset;
1501
40
  uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
1502
1503
40
  if (IsUnion) {
1504
11
    uint64_t RoundedFieldSize = roundUpSizeToCharAlignment(FieldSize,
1505
11
                                                           Context);
1506
11
    setDataSize(std::max(getDataSizeInBits(), RoundedFieldSize));
1507
11
    FieldOffset = 0;
1508
29
  } else {
1509
    // The bitfield is allocated starting at the next offset aligned
1510
    // appropriately for T', with length n bits.
1511
29
    FieldOffset = llvm::alignTo(getDataSizeInBits(), Context.toBits(TypeAlign));
1512
1513
29
    uint64_t NewSizeInBits = FieldOffset + FieldSize;
1514
1515
29
    setDataSize(
1516
29
        llvm::alignTo(NewSizeInBits, Context.getTargetInfo().getCharAlign()));
1517
29
    UnfilledBitsInLastUnit = getDataSizeInBits() - NewSizeInBits;
1518
29
  }
1519
1520
  // Place this field at the current location.
1521
40
  FieldOffsets.push_back(FieldOffset);
1522
1523
40
  CheckFieldPadding(FieldOffset, UnpaddedFieldOffset, FieldOffset,
1524
40
                    Context.toBits(TypeAlign), FieldPacked, D);
1525
1526
  // Update the size.
1527
40
  setSize(std::max(getSizeInBits(), getDataSizeInBits()));
1528
1529
  // Remember max struct/class alignment.
1530
40
  UpdateAlignment(TypeAlign);
1531
40
}
1532
1533
48.0k
static bool isAIXLayout(const ASTContext &Context) {
1534
48.0k
  return Context.getTargetInfo().getTriple().getOS() == llvm::Triple::AIX;
1535
48.0k
}
1536
1537
24.0k
void ItaniumRecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
1538
24.0k
  bool FieldPacked = Packed || 
D->hasAttr<PackedAttr>()20.2k
;
1539
24.0k
  uint64_t FieldSize = D->getBitWidthValue(Context);
1540
24.0k
  TypeInfo FieldInfo = Context.getTypeInfo(D->getType());
1541
24.0k
  uint64_t StorageUnitSize = FieldInfo.Width;
1542
24.0k
  unsigned FieldAlign = FieldInfo.Align;
1543
24.0k
  bool AlignIsRequired = FieldInfo.isAlignRequired();
1544
1545
  // UnfilledBitsInLastUnit is the difference between the end of the
1546
  // last allocated bitfield (i.e. the first bit offset available for
1547
  // bitfields) and the end of the current data size in bits (i.e. the
1548
  // first bit offset available for non-bitfields).  The current data
1549
  // size in bits is always a multiple of the char size; additionally,
1550
  // for ms_struct records it's also a multiple of the
1551
  // LastBitfieldStorageUnitSize (if set).
1552
1553
  // The struct-layout algorithm is dictated by the platform ABI,
1554
  // which in principle could use almost any rules it likes.  In
1555
  // practice, UNIXy targets tend to inherit the algorithm described
1556
  // in the System V generic ABI.  The basic bitfield layout rule in
1557
  // System V is to place bitfields at the next available bit offset
1558
  // where the entire bitfield would fit in an aligned storage unit of
1559
  // the declared type; it's okay if an earlier or later non-bitfield
1560
  // is allocated in the same storage unit.  However, some targets
1561
  // (those that !useBitFieldTypeAlignment(), e.g. ARM APCS) don't
1562
  // require this storage unit to be aligned, and therefore always put
1563
  // the bitfield at the next available bit offset.
1564
1565
  // ms_struct basically requests a complete replacement of the
1566
  // platform ABI's struct-layout algorithm, with the high-level goal
1567
  // of duplicating MSVC's layout.  For non-bitfields, this follows
1568
  // the standard algorithm.  The basic bitfield layout rule is to
1569
  // allocate an entire unit of the bitfield's declared type
1570
  // (e.g. 'unsigned long'), then parcel it up among successive
1571
  // bitfields whose declared types have the same size, making a new
1572
  // unit as soon as the last can no longer store the whole value.
1573
  // Since it completely replaces the platform ABI's algorithm,
1574
  // settings like !useBitFieldTypeAlignment() do not apply.
1575
1576
  // A zero-width bitfield forces the use of a new storage unit for
1577
  // later bitfields.  In general, this occurs by rounding up the
1578
  // current size of the struct as if the algorithm were about to
1579
  // place a non-bitfield of the field's formal type.  Usually this
1580
  // does not change the alignment of the struct itself, but it does
1581
  // on some targets (those that useZeroLengthBitfieldAlignment(),
1582
  // e.g. ARM).  In ms_struct layout, zero-width bitfields are
1583
  // ignored unless they follow a non-zero-width bitfield.
1584
1585
  // A field alignment restriction (e.g. from #pragma pack) or
1586
  // specification (e.g. from __attribute__((aligned))) changes the
1587
  // formal alignment of the field.  For System V, this alters the
1588
  // required alignment of the notional storage unit that must contain
1589
  // the bitfield.  For ms_struct, this only affects the placement of
1590
  // new storage units.  In both cases, the effect of #pragma pack is
1591
  // ignored on zero-width bitfields.
1592
1593
  // On System V, a packed field (e.g. from #pragma pack or
1594
  // __attribute__((packed))) always uses the next available bit
1595
  // offset.
1596
1597
  // In an ms_struct struct, the alignment of a fundamental type is
1598
  // always equal to its size.  This is necessary in order to mimic
1599
  // the i386 alignment rules on targets which might not fully align
1600
  // all types (e.g. Darwin PPC32, where alignof(long long) == 4).
1601
1602
  // First, some simple bookkeeping to perform for ms_struct structs.
1603
24.0k
  if (IsMsStruct) {
1604
    // The field alignment for integer types is always the size.
1605
307
    FieldAlign = StorageUnitSize;
1606
1607
    // If the previous field was not a bitfield, or was a bitfield
1608
    // with a different storage unit size, or if this field doesn't fit into
1609
    // the current storage unit, we're done with that storage unit.
1610
307
    if (LastBitfieldStorageUnitSize != StorageUnitSize ||
1611
307
        
UnfilledBitsInLastUnit < FieldSize55
) {
1612
      // Also, ignore zero-length bitfields after non-bitfields.
1613
272
      if (!LastBitfieldStorageUnitSize && 
!FieldSize173
)
1614
93
        FieldAlign = 1;
1615
1616
272
      UnfilledBitsInLastUnit = 0;
1617
272
      LastBitfieldStorageUnitSize = 0;
1618
272
    }
1619
307
  }
1620
1621
24.0k
  if (isAIXLayout(Context)) {
1622
228
    if (StorageUnitSize < Context.getTypeSize(Context.UnsignedIntTy)) {
1623
      // On AIX, [bool, char, short] bitfields have the same alignment
1624
      // as [unsigned].
1625
64
      StorageUnitSize = Context.getTypeSize(Context.UnsignedIntTy);
1626
164
    } else if (StorageUnitSize > Context.getTypeSize(Context.UnsignedIntTy) &&
1627
164
               
Context.getTargetInfo().getTriple().isArch32Bit()56
&&
1628
164
               
FieldSize <= 3220
) {
1629
      // Under 32-bit compile mode, the bitcontainer is 32 bits if a single
1630
      // long long bitfield has length no greater than 32 bits.
1631
18
      StorageUnitSize = 32;
1632
1633
18
      if (!AlignIsRequired)
1634
12
        FieldAlign = 32;
1635
18
    }
1636
1637
228
    if (FieldAlign < StorageUnitSize) {
1638
      // The bitfield alignment should always be greater than or equal to
1639
      // bitcontainer size.
1640
68
      FieldAlign = StorageUnitSize;
1641
68
    }
1642
228
  }
1643
1644
  // If the field is wider than its declared type, it follows
1645
  // different rules in all cases, except on AIX.
1646
  // On AIX, wide bitfield follows the same rules as normal bitfield.
1647
24.0k
  if (FieldSize > StorageUnitSize && 
!isAIXLayout(Context)40
) {
1648
40
    LayoutWideBitField(FieldSize, StorageUnitSize, FieldPacked, D);
1649
40
    return;
1650
40
  }
1651
1652
  // Compute the next available bit offset.
1653
24.0k
  uint64_t FieldOffset =
1654
24.0k
    IsUnion ? 
0138
:
(getDataSizeInBits() - UnfilledBitsInLastUnit)23.8k
;
1655
1656
  // Handle targets that don't honor bitfield type alignment.
1657
24.0k
  if (!IsMsStruct && 
!Context.getTargetInfo().useBitFieldTypeAlignment()23.7k
) {
1658
    // Some such targets do honor it on zero-width bitfields.
1659
157
    if (FieldSize == 0 &&
1660
157
        
Context.getTargetInfo().useZeroLengthBitfieldAlignment()79
) {
1661
      // Some targets don't honor leading zero-width bitfield.
1662
77
      if (!IsUnion && 
FieldOffset == 069
&&
1663
77
          
!Context.getTargetInfo().useLeadingZeroLengthBitfield()22
)
1664
12
        FieldAlign = 1;
1665
65
      else {
1666
        // The alignment to round up to is the max of the field's natural
1667
        // alignment and a target-specific fixed value (sometimes zero).
1668
65
        unsigned ZeroLengthBitfieldBoundary =
1669
65
            Context.getTargetInfo().getZeroLengthBitfieldBoundary();
1670
65
        FieldAlign = std::max(FieldAlign, ZeroLengthBitfieldBoundary);
1671
65
      }
1672
    // If that doesn't apply, just ignore the field alignment.
1673
80
    } else {
1674
80
      FieldAlign = 1;
1675
80
    }
1676
157
  }
1677
1678
  // Remember the alignment we would have used if the field were not packed.
1679
24.0k
  unsigned UnpackedFieldAlign = FieldAlign;
1680
1681
  // Ignore the field alignment if the field is packed unless it has zero-size.
1682
24.0k
  if (!IsMsStruct && 
FieldPacked23.7k
&&
FieldSize != 03.84k
)
1683
3.82k
    FieldAlign = 1;
1684
1685
  // But, if there's an 'aligned' attribute on the field, honor that.
1686
24.0k
  unsigned ExplicitFieldAlign = D->getMaxAlignment();
1687
24.0k
  if (ExplicitFieldAlign) {
1688
164
    FieldAlign = std::max(FieldAlign, ExplicitFieldAlign);
1689
164
    UnpackedFieldAlign = std::max(UnpackedFieldAlign, ExplicitFieldAlign);
1690
164
  }
1691
1692
  // But, if there's a #pragma pack in play, that takes precedent over
1693
  // even the 'aligned' attribute, for non-zero-width bitfields.
1694
24.0k
  unsigned MaxFieldAlignmentInBits = Context.toBits(MaxFieldAlignment);
1695
24.0k
  if (!MaxFieldAlignment.isZero() && 
FieldSize4.13k
) {
1696
4.11k
    UnpackedFieldAlign = std::min(UnpackedFieldAlign, MaxFieldAlignmentInBits);
1697
4.11k
    if (FieldPacked)
1698
34
      FieldAlign = UnpackedFieldAlign;
1699
4.07k
    else
1700
4.07k
      FieldAlign = std::min(FieldAlign, MaxFieldAlignmentInBits);
1701
4.11k
  }
1702
1703
  // But, ms_struct just ignores all of that in unions, even explicit
1704
  // alignment attributes.
1705
24.0k
  if (IsMsStruct && 
IsUnion307
) {
1706
8
    FieldAlign = UnpackedFieldAlign = 1;
1707
8
  }
1708
1709
  // For purposes of diagnostics, we're going to simultaneously
1710
  // compute the field offsets that we would have used if we weren't
1711
  // adding any alignment padding or if the field weren't packed.
1712
24.0k
  uint64_t UnpaddedFieldOffset = FieldOffset;
1713
24.0k
  uint64_t UnpackedFieldOffset = FieldOffset;
1714
1715
  // Check if we need to add padding to fit the bitfield within an
1716
  // allocation unit with the right size and alignment.  The rules are
1717
  // somewhat different here for ms_struct structs.
1718
24.0k
  if (IsMsStruct) {
1719
    // If it's not a zero-width bitfield, and we can fit the bitfield
1720
    // into the active storage unit (and we haven't already decided to
1721
    // start a new storage unit), just do so, regardless of any other
1722
    // other consideration.  Otherwise, round up to the right alignment.
1723
307
    if (FieldSize == 0 || 
FieldSize > UnfilledBitsInLastUnit199
) {
1724
275
      FieldOffset = llvm::alignTo(FieldOffset, FieldAlign);
1725
275
      UnpackedFieldOffset =
1726
275
          llvm::alignTo(UnpackedFieldOffset, UnpackedFieldAlign);
1727
275
      UnfilledBitsInLastUnit = 0;
1728
275
    }
1729
1730
23.7k
  } else {
1731
    // #pragma pack, with any value, suppresses the insertion of padding.
1732
23.7k
    bool AllowPadding = MaxFieldAlignment.isZero();
1733
1734
    // Compute the real offset.
1735
23.7k
    if (FieldSize == 0 ||
1736
23.7k
        
(23.1k
AllowPadding23.1k
&&
1737
23.1k
         
(FieldOffset & (FieldAlign - 1)) + FieldSize > StorageUnitSize19.1k
)) {
1738
639
      FieldOffset = llvm::alignTo(FieldOffset, FieldAlign);
1739
23.0k
    } else if (ExplicitFieldAlign &&
1740
23.0k
               
(133
MaxFieldAlignmentInBits == 0133
||
1741
133
                
ExplicitFieldAlign <= MaxFieldAlignmentInBits24
) &&
1742
23.0k
               
Context.getTargetInfo().useExplicitBitFieldAlignment()125
) {
1743
      // TODO: figure it out what needs to be done on targets that don't honor
1744
      // bit-field type alignment like ARM APCS ABI.
1745
105
      FieldOffset = llvm::alignTo(FieldOffset, ExplicitFieldAlign);
1746
105
    }
1747
1748
    // Repeat the computation for diagnostic purposes.
1749
23.7k
    if (FieldSize == 0 ||
1750
23.7k
        
(23.1k
AllowPadding23.1k
&&
1751
23.1k
         (UnpackedFieldOffset & (UnpackedFieldAlign - 1)) + FieldSize >
1752
19.1k
             StorageUnitSize))
1753
697
      UnpackedFieldOffset =
1754
697
          llvm::alignTo(UnpackedFieldOffset, UnpackedFieldAlign);
1755
23.0k
    else if (ExplicitFieldAlign &&
1756
23.0k
             
(128
MaxFieldAlignmentInBits == 0128
||
1757
128
              
ExplicitFieldAlign <= MaxFieldAlignmentInBits24
) &&
1758
23.0k
             
Context.getTargetInfo().useExplicitBitFieldAlignment()120
)
1759
101
      UnpackedFieldOffset =
1760
101
          llvm::alignTo(UnpackedFieldOffset, ExplicitFieldAlign);
1761
23.7k
  }
1762
1763
  // If we're using external layout, give the external layout a chance
1764
  // to override this information.
1765
24.0k
  if (UseExternalLayout)
1766
1.52k
    FieldOffset = updateExternalFieldOffset(D, FieldOffset);
1767
1768
  // Okay, place the bitfield at the calculated offset.
1769
24.0k
  FieldOffsets.push_back(FieldOffset);
1770
1771
  // Bookkeeping:
1772
1773
  // Anonymous members don't affect the overall record alignment,
1774
  // except on targets where they do.
1775
24.0k
  if (!IsMsStruct &&
1776
24.0k
      
!Context.getTargetInfo().useZeroLengthBitfieldAlignment()23.7k
&&
1777
24.0k
      
!D->getIdentifier()22.3k
)
1778
1.41k
    FieldAlign = UnpackedFieldAlign = 1;
1779
1780
  // On AIX, zero-width bitfields pad out to the natural alignment boundary,
1781
  // but do not increase the alignment greater than the MaxFieldAlignment, or 1
1782
  // if packed.
1783
24.0k
  if (isAIXLayout(Context) && 
!FieldSize228
) {
1784
44
    if (FieldPacked)
1785
8
      FieldAlign = 1;
1786
44
    if (!MaxFieldAlignment.isZero()) {
1787
12
      UnpackedFieldAlign =
1788
12
          std::min(UnpackedFieldAlign, MaxFieldAlignmentInBits);
1789
12
      FieldAlign = std::min(FieldAlign, MaxFieldAlignmentInBits);
1790
12
    }
1791
44
  }
1792
1793
  // Diagnose differences in layout due to padding or packing.
1794
24.0k
  if (!UseExternalLayout)
1795
22.4k
    CheckFieldPadding(FieldOffset, UnpaddedFieldOffset, UnpackedFieldOffset,
1796
22.4k
                      UnpackedFieldAlign, FieldPacked, D);
1797
1798
  // Update DataSize to include the last byte containing (part of) the bitfield.
1799
1800
  // For unions, this is just a max operation, as usual.
1801
24.0k
  if (IsUnion) {
1802
    // For ms_struct, allocate the entire storage unit --- unless this
1803
    // is a zero-width bitfield, in which case just use a size of 1.
1804
138
    uint64_t RoundedFieldSize;
1805
138
    if (IsMsStruct) {
1806
8
      RoundedFieldSize = (FieldSize ? 
StorageUnitSize5
1807
8
                                    : 
Context.getTargetInfo().getCharWidth()3
);
1808
1809
      // Otherwise, allocate just the number of bytes required to store
1810
      // the bitfield.
1811
130
    } else {
1812
130
      RoundedFieldSize = roundUpSizeToCharAlignment(FieldSize, Context);
1813
130
    }
1814
138
    setDataSize(std::max(getDataSizeInBits(), RoundedFieldSize));
1815
1816
  // For non-zero-width bitfields in ms_struct structs, allocate a new
1817
  // storage unit if necessary.
1818
23.8k
  } else if (IsMsStruct && 
FieldSize299
) {
1819
    // We should have cleared UnfilledBitsInLastUnit in every case
1820
    // where we changed storage units.
1821
194
    if (!UnfilledBitsInLastUnit) {
1822
162
      setDataSize(FieldOffset + StorageUnitSize);
1823
162
      UnfilledBitsInLastUnit = StorageUnitSize;
1824
162
    }
1825
194
    UnfilledBitsInLastUnit -= FieldSize;
1826
194
    LastBitfieldStorageUnitSize = StorageUnitSize;
1827
1828
    // Otherwise, bump the data size up to include the bitfield,
1829
    // including padding up to char alignment, and then remember how
1830
    // bits we didn't use.
1831
23.6k
  } else {
1832
23.6k
    uint64_t NewSizeInBits = FieldOffset + FieldSize;
1833
23.6k
    uint64_t CharAlignment = Context.getTargetInfo().getCharAlign();
1834
23.6k
    setDataSize(llvm::alignTo(NewSizeInBits, CharAlignment));
1835
23.6k
    UnfilledBitsInLastUnit = getDataSizeInBits() - NewSizeInBits;
1836
1837
    // The only time we can get here for an ms_struct is if this is a
1838
    // zero-width bitfield, which doesn't count as anything for the
1839
    // purposes of unfilled bits.
1840
23.6k
    LastBitfieldStorageUnitSize = 0;
1841
23.6k
  }
1842
1843
  // Update the size.
1844
24.0k
  setSize(std::max(getSizeInBits(), getDataSizeInBits()));
1845
1846
  // Remember max struct/class alignment.
1847
24.0k
  UnadjustedAlignment =
1848
24.0k
      std::max(UnadjustedAlignment, Context.toCharUnitsFromBits(FieldAlign));
1849
24.0k
  UpdateAlignment(Context.toCharUnitsFromBits(FieldAlign),
1850
24.0k
                  Context.toCharUnitsFromBits(UnpackedFieldAlign));
1851
24.0k
}
1852
1853
void ItaniumRecordLayoutBuilder::LayoutField(const FieldDecl *D,
1854
868k
                                             bool InsertExtraPadding) {
1855
868k
  auto *FieldClass = D->getType()->getAsCXXRecordDecl();
1856
868k
  bool PotentiallyOverlapping = D->hasAttr<NoUniqueAddressAttr>() && 
FieldClass139
;
1857
868k
  bool IsOverlappingEmptyField =
1858
868k
      PotentiallyOverlapping && 
FieldClass->isEmpty()129
;
1859
1860
868k
  CharUnits FieldOffset =
1861
868k
      (IsUnion || 
IsOverlappingEmptyField820k
) ?
CharUnits::Zero()47.5k
:
getDataSize()820k
;
1862
1863
868k
  const bool DefaultsToAIXPowerAlignment =
1864
868k
      Context.getTargetInfo().defaultsToAIXPowerAlignment();
1865
868k
  bool FoundFirstNonOverlappingEmptyFieldForAIX = false;
1866
868k
  if (DefaultsToAIXPowerAlignment && 
!HandledFirstNonOverlappingEmptyField578
) {
1867
269
    assert(FieldOffset == CharUnits::Zero() &&
1868
269
           "The first non-overlapping empty field should have been handled.");
1869
1870
269
    if (!IsOverlappingEmptyField) {
1871
261
      FoundFirstNonOverlappingEmptyFieldForAIX = true;
1872
1873
      // We're going to handle the "first member" based on
1874
      // `FoundFirstNonOverlappingEmptyFieldForAIX` during the current
1875
      // invocation of this function; record it as handled for future
1876
      // invocations (except for unions, because the current field does not
1877
      // represent all "firsts").
1878
261
      HandledFirstNonOverlappingEmptyField = !IsUnion;
1879
261
    }
1880
269
  }
1881
1882
868k
  if (D->isBitField()) {
1883
24.0k
    LayoutBitField(D);
1884
24.0k
    return;
1885
24.0k
  }
1886
1887
844k
  uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
1888
  // Reset the unfilled bits.
1889
844k
  UnfilledBitsInLastUnit = 0;
1890
844k
  LastBitfieldStorageUnitSize = 0;
1891
1892
844k
  llvm::Triple Target = Context.getTargetInfo().getTriple();
1893
844k
  bool FieldPacked = (Packed && 
(17.1k
!FieldClass17.1k
||
FieldClass->isPOD()351
||
1894
17.1k
                                 Context.getLangOpts().getClangABICompat() <=
1895
18
                                     LangOptions::ClangABI::Ver14 ||
1896
17.1k
                                 
Target.isPS()14
||
Target.isOSDarwin()10
)) ||
1897
844k
                     
D->hasAttr<PackedAttr>()827k
;
1898
1899
844k
  AlignRequirementKind AlignRequirement = AlignRequirementKind::None;
1900
844k
  CharUnits FieldSize;
1901
844k
  CharUnits FieldAlign;
1902
  // The amount of this class's dsize occupied by the field.
1903
  // This is equal to FieldSize unless we're permitted to pack
1904
  // into the field's tail padding.
1905
844k
  CharUnits EffectiveFieldSize;
1906
1907
844k
  auto setDeclInfo = [&](bool IsIncompleteArrayType) {
1908
838k
    auto TI = Context.getTypeInfoInChars(D->getType());
1909
838k
    FieldAlign = TI.Align;
1910
    // Flexible array members don't have any size, but they have to be
1911
    // aligned appropriately for their element type.
1912
838k
    EffectiveFieldSize = FieldSize =
1913
838k
        IsIncompleteArrayType ? 
CharUnits::Zero()339
:
TI.Width837k
;
1914
838k
    AlignRequirement = TI.AlignRequirement;
1915
838k
  };
1916
1917
844k
  if (D->getType()->isIncompleteArrayType()) {
1918
339
    setDeclInfo(true /* IsIncompleteArrayType */);
1919
844k
  } else if (const ReferenceType *RT = D->getType()->getAs<ReferenceType>()) {
1920
6.28k
    unsigned AS = Context.getTargetAddressSpace(RT->getPointeeType());
1921
6.28k
    EffectiveFieldSize = FieldSize = Context.toCharUnitsFromBits(
1922
6.28k
        Context.getTargetInfo().getPointerWidth(AS));
1923
6.28k
    FieldAlign = Context.toCharUnitsFromBits(
1924
6.28k
        Context.getTargetInfo().getPointerAlign(AS));
1925
837k
  } else {
1926
837k
    setDeclInfo(false /* IsIncompleteArrayType */);
1927
1928
    // A potentially-overlapping field occupies its dsize or nvsize, whichever
1929
    // is larger.
1930
837k
    if (PotentiallyOverlapping) {
1931
129
      const ASTRecordLayout &Layout = Context.getASTRecordLayout(FieldClass);
1932
129
      EffectiveFieldSize =
1933
129
          std::max(Layout.getNonVirtualSize(), Layout.getDataSize());
1934
129
    }
1935
1936
837k
    if (IsMsStruct) {
1937
      // If MS bitfield layout is required, figure out what type is being
1938
      // laid out and align the field to the width of that type.
1939
1940
      // Resolve all typedefs down to their base type and round up the field
1941
      // alignment if necessary.
1942
173
      QualType T = Context.getBaseElementType(D->getType());
1943
173
      if (const BuiltinType *BTy = T->getAs<BuiltinType>()) {
1944
166
        CharUnits TypeSize = Context.getTypeSizeInChars(BTy);
1945
1946
166
        if (!llvm::isPowerOf2_64(TypeSize.getQuantity())) {
1947
4
          assert(
1948
4
              !Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment() &&
1949
4
              "Non PowerOf2 size in MSVC mode");
1950
          // Base types with sizes that aren't a power of two don't work
1951
          // with the layout rules for MS structs. This isn't an issue in
1952
          // MSVC itself since there are no such base data types there.
1953
          // On e.g. x86_32 mingw and linux, long double is 12 bytes though.
1954
          // Any structs involving that data type obviously can't be ABI
1955
          // compatible with MSVC regardless of how it is laid out.
1956
1957
          // Since ms_struct can be mass enabled (via a pragma or via the
1958
          // -mms-bitfields command line parameter), this can trigger for
1959
          // structs that don't actually need MSVC compatibility, so we
1960
          // need to be able to sidestep the ms_struct layout for these types.
1961
1962
          // Since the combination of -mms-bitfields together with structs
1963
          // like max_align_t (which contains a long double) for mingw is
1964
          // quite common (and GCC handles it silently), just handle it
1965
          // silently there. For other targets that have ms_struct enabled
1966
          // (most probably via a pragma or attribute), trigger a diagnostic
1967
          // that defaults to an error.
1968
4
          if (!Context.getTargetInfo().getTriple().isWindowsGNUEnvironment())
1969
2
            Diag(D->getLocation(), diag::warn_npot_ms_struct);
1970
4
        }
1971
166
        if (TypeSize > FieldAlign &&
1972
166
            
llvm::isPowerOf2_64(TypeSize.getQuantity())13
)
1973
9
          FieldAlign = TypeSize;
1974
166
      }
1975
173
    }
1976
837k
  }
1977
1978
  // When used as part of a typedef, or together with a 'packed' attribute, the
1979
  // 'aligned' attribute can be used to decrease alignment. In that case, it
1980
  // overrides any computed alignment we have, and there is no need to upgrade
1981
  // the alignment.
1982
350
  auto alignedAttrCanDecreaseAIXAlignment = [AlignRequirement, FieldPacked] {
1983
    // Enum alignment sources can be safely ignored here, because this only
1984
    // helps decide whether we need the AIX alignment upgrade, which only
1985
    // applies to floating-point types.
1986
350
    return AlignRequirement == AlignRequirementKind::RequiredByTypedef ||
1987
350
           
(342
AlignRequirement == AlignRequirementKind::RequiredByRecord342
&&
1988
342
            
FieldPacked4
);
1989
350
  };
1990
1991
  // The AIX `power` alignment rules apply the natural alignment of the
1992
  // "first member" if it is of a floating-point data type (or is an aggregate
1993
  // whose recursively "first" member or element is such a type). The alignment
1994
  // associated with these types for subsequent members use an alignment value
1995
  // where the floating-point data type is considered to have 4-byte alignment.
1996
  //
1997
  // For the purposes of the foregoing: vtable pointers, non-empty base classes,
1998
  // and zero-width bit-fields count as prior members; members of empty class
1999
  // types marked `no_unique_address` are not considered to be prior members.
2000
844k
  CharUnits PreferredAlign = FieldAlign;
2001
844k
  if (DefaultsToAIXPowerAlignment && 
!alignedAttrCanDecreaseAIXAlignment()350
&&
2002
844k
      
(342
FoundFirstNonOverlappingEmptyFieldForAIX342
||
IsNaturalAlign165
)) {
2003
221
    auto performBuiltinTypeAlignmentUpgrade = [&](const BuiltinType *BTy) {
2004
181
      if (BTy->getKind() == BuiltinType::Double ||
2005
181
          
BTy->getKind() == BuiltinType::LongDouble115
) {
2006
68
        assert(PreferredAlign == CharUnits::fromQuantity(4) &&
2007
68
               "No need to upgrade the alignment value.");
2008
0
        PreferredAlign = CharUnits::fromQuantity(8);
2009
68
      }
2010
181
    };
2011
2012
221
    const Type *BaseTy = D->getType()->getBaseElementTypeUnsafe();
2013
221
    if (const ComplexType *CTy = BaseTy->getAs<ComplexType>()) {
2014
2
      performBuiltinTypeAlignmentUpgrade(
2015
2
          CTy->getElementType()->castAs<BuiltinType>());
2016
219
    } else if (const BuiltinType *BTy = BaseTy->getAs<BuiltinType>()) {
2017
179
      performBuiltinTypeAlignmentUpgrade(BTy);
2018
179
    } else 
if (const RecordType *40
RT40
= BaseTy->getAs<RecordType>()) {
2019
36
      const RecordDecl *RD = RT->getDecl();
2020
36
      assert(RD && "Expected non-null RecordDecl.");
2021
0
      const ASTRecordLayout &FieldRecord = Context.getASTRecordLayout(RD);
2022
36
      PreferredAlign = FieldRecord.getPreferredAlignment();
2023
36
    }
2024
221
  }
2025
2026
  // The align if the field is not packed. This is to check if the attribute
2027
  // was unnecessary (-Wpacked).
2028
0
  CharUnits UnpackedFieldAlign =
2029
844k
      !DefaultsToAIXPowerAlignment ? 
FieldAlign844k
:
PreferredAlign350
;
2030
844k
  CharUnits UnpackedFieldOffset = FieldOffset;
2031
844k
  CharUnits OriginalFieldAlign = UnpackedFieldAlign;
2032
2033
844k
  if (FieldPacked) {
2034
18.0k
    FieldAlign = CharUnits::One();
2035
18.0k
    PreferredAlign = CharUnits::One();
2036
18.0k
  }
2037
844k
  CharUnits MaxAlignmentInChars =
2038
844k
      Context.toCharUnitsFromBits(D->getMaxAlignment());
2039
844k
  FieldAlign = std::max(FieldAlign, MaxAlignmentInChars);
2040
844k
  PreferredAlign = std::max(PreferredAlign, MaxAlignmentInChars);
2041
844k
  UnpackedFieldAlign = std::max(UnpackedFieldAlign, MaxAlignmentInChars);
2042
2043
  // The maximum field alignment overrides the aligned attribute.
2044
844k
  if (!MaxFieldAlignment.isZero()) {
2045
179k
    FieldAlign = std::min(FieldAlign, MaxFieldAlignment);
2046
179k
    PreferredAlign = std::min(PreferredAlign, MaxFieldAlignment);
2047
179k
    UnpackedFieldAlign = std::min(UnpackedFieldAlign, MaxFieldAlignment);
2048
179k
  }
2049
2050
844k
  CharUnits AlignTo =
2051
844k
      !DefaultsToAIXPowerAlignment ? 
FieldAlign844k
:
PreferredAlign350
;
2052
  // Round up the current record size to the field's alignment boundary.
2053
844k
  FieldOffset = FieldOffset.alignTo(AlignTo);
2054
844k
  UnpackedFieldOffset = UnpackedFieldOffset.alignTo(UnpackedFieldAlign);
2055
2056
844k
  if (UseExternalLayout) {
2057
32.3k
    FieldOffset = Context.toCharUnitsFromBits(
2058
32.3k
        updateExternalFieldOffset(D, Context.toBits(FieldOffset)));
2059
2060
32.3k
    if (!IsUnion && 
EmptySubobjects29.8k
) {
2061
      // Record the fact that we're placing a field at this offset.
2062
29.7k
      bool Allowed = EmptySubobjects->CanPlaceFieldAtOffset(D, FieldOffset);
2063
29.7k
      (void)Allowed;
2064
29.7k
      assert(Allowed && "Externally-placed field cannot be placed here");
2065
29.7k
    }
2066
812k
  } else {
2067
812k
    if (!IsUnion && 
EmptySubobjects767k
) {
2068
      // Check if we can place the field at this offset.
2069
360k
      while (!EmptySubobjects->CanPlaceFieldAtOffset(D, FieldOffset)) {
2070
        // We couldn't place the field at the offset. Try again at a new offset.
2071
        // We try offset 0 (for an empty field) and then dsize(C) onwards.
2072
75
        if (FieldOffset == CharUnits::Zero() &&
2073
75
            
getDataSize() != CharUnits::Zero()68
)
2074
11
          FieldOffset = getDataSize().alignTo(AlignTo);
2075
64
        else
2076
64
          FieldOffset += AlignTo;
2077
75
      }
2078
360k
    }
2079
812k
  }
2080
2081
  // Place this field at the current location.
2082
0
  FieldOffsets.push_back(Context.toBits(FieldOffset));
2083
2084
844k
  if (!UseExternalLayout)
2085
812k
    CheckFieldPadding(Context.toBits(FieldOffset), UnpaddedFieldOffset,
2086
812k
                      Context.toBits(UnpackedFieldOffset),
2087
812k
                      Context.toBits(UnpackedFieldAlign), FieldPacked, D);
2088
2089
844k
  if (InsertExtraPadding) {
2090
36
    CharUnits ASanAlignment = CharUnits::fromQuantity(8);
2091
36
    CharUnits ExtraSizeForAsan = ASanAlignment;
2092
36
    if (FieldSize % ASanAlignment)
2093
30
      ExtraSizeForAsan +=
2094
30
          ASanAlignment - CharUnits::fromQuantity(FieldSize % ASanAlignment);
2095
36
    EffectiveFieldSize = FieldSize = FieldSize + ExtraSizeForAsan;
2096
36
  }
2097
2098
  // Reserve space for this field.
2099
844k
  if (!IsOverlappingEmptyField) {
2100
844k
    uint64_t EffectiveFieldSizeInBits = Context.toBits(EffectiveFieldSize);
2101
844k
    if (IsUnion)
2102
47.3k
      setDataSize(std::max(getDataSizeInBits(), EffectiveFieldSizeInBits));
2103
796k
    else
2104
796k
      setDataSize(FieldOffset + EffectiveFieldSize);
2105
2106
844k
    PaddedFieldSize = std::max(PaddedFieldSize, FieldOffset + FieldSize);
2107
844k
    setSize(std::max(getSizeInBits(), getDataSizeInBits()));
2108
844k
  } else {
2109
106
    setSize(std::max(getSizeInBits(),
2110
106
                     (uint64_t)Context.toBits(FieldOffset + FieldSize)));
2111
106
  }
2112
2113
  // Remember max struct/class ABI-specified alignment.
2114
844k
  UnadjustedAlignment = std::max(UnadjustedAlignment, FieldAlign);
2115
844k
  UpdateAlignment(FieldAlign, UnpackedFieldAlign, PreferredAlign);
2116
2117
  // For checking the alignment of inner fields against
2118
  // the alignment of its parent record.
2119
844k
  if (const RecordDecl *RD = D->getParent()) {
2120
    // Check if packed attribute or pragma pack is present.
2121
838k
    if (RD->hasAttr<PackedAttr>() || 
!MaxFieldAlignment.isZero()821k
)
2122
196k
      if (FieldAlign < OriginalFieldAlign)
2123
67.7k
        if (D->getType()->isRecordType()) {
2124
          // If the offset is a multiple of the alignment of
2125
          // the type, raise the warning.
2126
          // TODO: Takes no account the alignment of the outer struct
2127
1.10k
          if (FieldOffset % OriginalFieldAlign != 0)
2128
177
            Diag(D->getLocation(), diag::warn_unaligned_access)
2129
177
                << Context.getTypeDeclType(RD) << D->getName() << D->getType();
2130
1.10k
        }
2131
838k
  }
2132
844k
}
2133
2134
413k
void ItaniumRecordLayoutBuilder::FinishLayout(const NamedDecl *D) {
2135
  // In C++, records cannot be of size 0.
2136
413k
  if (Context.getLangOpts().CPlusPlus && 
getSizeInBits() == 0326k
) {
2137
84.0k
    if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
2138
      // Compatibility with gcc requires a class (pod or non-pod)
2139
      // which is not empty but of size 0; such as having fields of
2140
      // array of zero-length, remains of Size 0
2141
83.9k
      if (RD->isEmpty())
2142
82.9k
        setSize(CharUnits::One());
2143
83.9k
    }
2144
64
    else
2145
64
      setSize(CharUnits::One());
2146
84.0k
  }
2147
2148
  // If we have any remaining field tail padding, include that in the overall
2149
  // size.
2150
413k
  setSize(std::max(getSizeInBits(), (uint64_t)Context.toBits(PaddedFieldSize)));
2151
2152
  // Finally, round the size of the record up to the alignment of the
2153
  // record itself.
2154
413k
  uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastUnit;
2155
413k
  uint64_t UnpackedSizeInBits =
2156
413k
      llvm::alignTo(getSizeInBits(), Context.toBits(UnpackedAlignment));
2157
2158
413k
  uint64_t RoundedSize = llvm::alignTo(
2159
413k
      getSizeInBits(),
2160
413k
      Context.toBits(!Context.getTargetInfo().defaultsToAIXPowerAlignment()
2161
413k
                         ? 
Alignment412k
2162
413k
                         : 
PreferredAlignment397
));
2163
2164
413k
  if (UseExternalLayout) {
2165
    // If we're inferring alignment, and the external size is smaller than
2166
    // our size after we've rounded up to alignment, conservatively set the
2167
    // alignment to 1.
2168
30.2k
    if (InferAlignment && 
External.Size < RoundedSize4.68k
) {
2169
3
      Alignment = CharUnits::One();
2170
3
      PreferredAlignment = CharUnits::One();
2171
3
      InferAlignment = false;
2172
3
    }
2173
30.2k
    setSize(External.Size);
2174
30.2k
    return;
2175
30.2k
  }
2176
2177
  // Set the size to the final size.
2178
383k
  setSize(RoundedSize);
2179
2180
383k
  unsigned CharBitNum = Context.getTargetInfo().getCharWidth();
2181
383k
  if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) {
2182
    // Warn if padding was introduced to the struct/class/union.
2183
377k
    if (getSizeInBits() > UnpaddedSize) {
2184
16.0k
      unsigned PadSize = getSizeInBits() - UnpaddedSize;
2185
16.0k
      bool InBits = true;
2186
16.0k
      if (PadSize % CharBitNum == 0) {
2187
15.2k
        PadSize = PadSize / CharBitNum;
2188
15.2k
        InBits = false;
2189
15.2k
      }
2190
16.0k
      Diag(RD->getLocation(), diag::warn_padded_struct_size)
2191
16.0k
          << Context.getTypeDeclType(RD)
2192
16.0k
          << PadSize
2193
16.0k
          << (InBits ? 
1793
:
015.2k
); // (byte|bit)
2194
16.0k
    }
2195
2196
    // Warn if we packed it unnecessarily, when the unpacked alignment is not
2197
    // greater than the one after packing, the size in bits doesn't change and
2198
    // the offset of each field is identical.
2199
377k
    if (Packed && 
UnpackedAlignment <= Alignment7.62k
&&
2200
377k
        
UnpackedSizeInBits == getSizeInBits()1.83k
&&
!HasPackedField1.83k
)
2201
1.81k
      Diag(D->getLocation(), diag::warn_unnecessary_packed)
2202
1.81k
          << Context.getTypeDeclType(RD);
2203
377k
  }
2204
383k
}
2205
2206
void ItaniumRecordLayoutBuilder::UpdateAlignment(
2207
    CharUnits NewAlignment, CharUnits UnpackedNewAlignment,
2208
952k
    CharUnits PreferredNewAlignment) {
2209
  // The alignment is not modified when using 'mac68k' alignment or when
2210
  // we have an externally-supplied layout that also provides overall alignment.
2211
952k
  if (IsMac68kAlign || 
(952k
UseExternalLayout952k
&&
!InferAlignment48.7k
))
2212
40.5k
    return;
2213
2214
911k
  if (NewAlignment > Alignment) {
2215
283k
    assert(llvm::isPowerOf2_64(NewAlignment.getQuantity()) &&
2216
283k
           "Alignment not a power of 2");
2217
0
    Alignment = NewAlignment;
2218
283k
  }
2219
2220
911k
  if (UnpackedNewAlignment > UnpackedAlignment) {
2221
290k
    assert(llvm::isPowerOf2_64(UnpackedNewAlignment.getQuantity()) &&
2222
290k
           "Alignment not a power of 2");
2223
0
    UnpackedAlignment = UnpackedNewAlignment;
2224
290k
  }
2225
2226
911k
  if (PreferredNewAlignment > PreferredAlignment) {
2227
283k
    assert(llvm::isPowerOf2_64(PreferredNewAlignment.getQuantity()) &&
2228
283k
           "Alignment not a power of 2");
2229
0
    PreferredAlignment = PreferredNewAlignment;
2230
283k
  }
2231
911k
}
2232
2233
uint64_t
2234
ItaniumRecordLayoutBuilder::updateExternalFieldOffset(const FieldDecl *Field,
2235
33.8k
                                                      uint64_t ComputedOffset) {
2236
33.8k
  uint64_t ExternalFieldOffset = External.getExternalFieldOffset(Field);
2237
2238
33.8k
  if (InferAlignment && 
ExternalFieldOffset < ComputedOffset6.44k
) {
2239
    // The externally-supplied field offset is before the field offset we
2240
    // computed. Assume that the structure is packed.
2241
9
    Alignment = CharUnits::One();
2242
9
    PreferredAlignment = CharUnits::One();
2243
9
    InferAlignment = false;
2244
9
  }
2245
2246
  // Use the externally-supplied field offset.
2247
33.8k
  return ExternalFieldOffset;
2248
33.8k
}
2249
2250
/// Get diagnostic %select index for tag kind for
2251
/// field padding diagnostic message.
2252
/// WARNING: Indexes apply to particular diagnostics only!
2253
///
2254
/// \returns diagnostic %select index.
2255
19.3k
static unsigned getPaddingDiagFromTagKind(TagTypeKind Tag) {
2256
19.3k
  switch (Tag) {
2257
18.0k
  case TTK_Struct: return 0;
2258
0
  case TTK_Interface: return 1;
2259
1.36k
  case TTK_Class: return 2;
2260
0
  default: llvm_unreachable("Invalid tag kind for field padding diagnostic!");
2261
19.3k
  }
2262
19.3k
}
2263
2264
void ItaniumRecordLayoutBuilder::CheckFieldPadding(
2265
    uint64_t Offset, uint64_t UnpaddedOffset, uint64_t UnpackedOffset,
2266
834k
    unsigned UnpackedAlign, bool isPacked, const FieldDecl *D) {
2267
  // We let objc ivars without warning, objc interfaces generally are not used
2268
  // for padding tricks.
2269
834k
  if (isa<ObjCIvarDecl>(D))
2270
6.60k
    return;
2271
2272
  // Don't warn about structs created without a SourceLocation.  This can
2273
  // be done by clients of the AST, such as codegen.
2274
827k
  if (D->getLocation().isInvalid())
2275
84.7k
    return;
2276
2277
743k
  unsigned CharBitNum = Context.getTargetInfo().getCharWidth();
2278
2279
  // Warn if padding was introduced to the struct/class.
2280
743k
  if (!IsUnion && 
Offset > UnpaddedOffset699k
) {
2281
19.3k
    unsigned PadSize = Offset - UnpaddedOffset;
2282
19.3k
    bool InBits = true;
2283
19.3k
    if (PadSize % CharBitNum == 0) {
2284
18.7k
      PadSize = PadSize / CharBitNum;
2285
18.7k
      InBits = false;
2286
18.7k
    }
2287
19.3k
    if (D->getIdentifier())
2288
19.0k
      Diag(D->getLocation(), diag::warn_padded_struct_field)
2289
19.0k
          << getPaddingDiagFromTagKind(D->getParent()->getTagKind())
2290
19.0k
          << Context.getTypeDeclType(D->getParent())
2291
19.0k
          << PadSize
2292
19.0k
          << (InBits ? 
1484
:
018.5k
) // (byte|bit)
2293
19.0k
          << D->getIdentifier();
2294
358
    else
2295
358
      Diag(D->getLocation(), diag::warn_padded_struct_anon_field)
2296
358
          << getPaddingDiagFromTagKind(D->getParent()->getTagKind())
2297
358
          << Context.getTypeDeclType(D->getParent())
2298
358
          << PadSize
2299
358
          << (InBits ? 
190
:
0268
); // (byte|bit)
2300
19.3k
 }
2301
743k
 if (isPacked && 
Offset != UnpackedOffset21.8k
) {
2302
2.11k
   HasPackedField = true;
2303
2.11k
 }
2304
743k
}
2305
2306
static const CXXMethodDecl *computeKeyFunction(ASTContext &Context,
2307
145k
                                               const CXXRecordDecl *RD) {
2308
  // If a class isn't polymorphic it doesn't have a key function.
2309
145k
  if (!RD->isPolymorphic())
2310
120k
    return nullptr;
2311
2312
  // A class that is not externally visible doesn't have a key function. (Or
2313
  // at least, there's no point to assigning a key function to such a class;
2314
  // this doesn't affect the ABI.)
2315
25.0k
  if (!RD->isExternallyVisible())
2316
548
    return nullptr;
2317
2318
  // Template instantiations don't have key functions per Itanium C++ ABI 5.2.6.
2319
  // Same behavior as GCC.
2320
24.4k
  TemplateSpecializationKind TSK = RD->getTemplateSpecializationKind();
2321
24.4k
  if (TSK == TSK_ImplicitInstantiation ||
2322
24.4k
      
TSK == TSK_ExplicitInstantiationDeclaration21.9k
||
2323
24.4k
      
TSK == TSK_ExplicitInstantiationDefinition20.3k
)
2324
4.44k
    return nullptr;
2325
2326
20.0k
  bool allowInlineFunctions =
2327
20.0k
    Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline();
2328
2329
82.9k
  for (const CXXMethodDecl *MD : RD->methods()) {
2330
82.9k
    if (!MD->isVirtual())
2331
60.6k
      continue;
2332
2333
22.2k
    if (MD->isPure())
2334
703
      continue;
2335
2336
    // Ignore implicit member functions, they are always marked as inline, but
2337
    // they don't have a body until they're defined.
2338
21.5k
    if (MD->isImplicit())
2339
860
      continue;
2340
2341
20.7k
    if (MD->isInlineSpecified() || 
MD->isConstexpr()20.6k
)
2342
137
      continue;
2343
2344
20.5k
    if (MD->hasInlineBody())
2345
5.70k
      continue;
2346
2347
    // Ignore inline deleted or defaulted functions.
2348
14.8k
    if (!MD->isUserProvided())
2349
71
      continue;
2350
2351
    // In certain ABIs, ignore functions with out-of-line inline definitions.
2352
14.8k
    if (!allowInlineFunctions) {
2353
225
      const FunctionDecl *Def;
2354
225
      if (MD->hasBody(Def) && 
Def->isInlineSpecified()159
)
2355
88
        continue;
2356
225
    }
2357
2358
14.7k
    if (Context.getLangOpts().CUDA) {
2359
      // While compiler may see key method in this TU, during CUDA
2360
      // compilation we should ignore methods that are not accessible
2361
      // on this side of compilation.
2362
0
      if (Context.getLangOpts().CUDAIsDevice) {
2363
        // In device mode ignore methods without __device__ attribute.
2364
0
        if (!MD->hasAttr<CUDADeviceAttr>())
2365
0
          continue;
2366
0
      } else {
2367
        // In host mode ignore __device__-only methods.
2368
0
        if (!MD->hasAttr<CUDAHostAttr>() && MD->hasAttr<CUDADeviceAttr>())
2369
0
          continue;
2370
0
      }
2371
0
    }
2372
2373
    // If the key function is dllimport but the class isn't, then the class has
2374
    // no key function. The DLL that exports the key function won't export the
2375
    // vtable in this case.
2376
14.7k
    if (MD->hasAttr<DLLImportAttr>() && 
!RD->hasAttr<DLLImportAttr>()104
&&
2377
14.7k
        
!Context.getTargetInfo().hasPS4DLLImportExport()93
)
2378
78
      return nullptr;
2379
2380
    // We found it.
2381
14.6k
    return MD;
2382
14.7k
  }
2383
2384
5.31k
  return nullptr;
2385
20.0k
}
2386
2387
DiagnosticBuilder ItaniumRecordLayoutBuilder::Diag(SourceLocation Loc,
2388
37.3k
                                                   unsigned DiagID) {
2389
37.3k
  return Context.getDiagnostics().Report(Loc, DiagID);
2390
37.3k
}
2391
2392
/// Does the target C++ ABI require us to skip over the tail-padding
2393
/// of the given class (considering it as a base class) when allocating
2394
/// objects?
2395
294k
static bool mustSkipTailPadding(TargetCXXABI ABI, const CXXRecordDecl *RD) {
2396
294k
  switch (ABI.getTailPaddingUseRules()) {
2397
0
  case TargetCXXABI::AlwaysUseTailPadding:
2398
0
    return false;
2399
2400
294k
  case TargetCXXABI::UseTailPaddingUnlessPOD03:
2401
    // FIXME: To the extent that this is meant to cover the Itanium ABI
2402
    // rules, we should implement the restrictions about over-sized
2403
    // bitfields:
2404
    //
2405
    // http://itanium-cxx-abi.github.io/cxx-abi/abi.html#POD :
2406
    //   In general, a type is considered a POD for the purposes of
2407
    //   layout if it is a POD type (in the sense of ISO C++
2408
    //   [basic.types]). However, a POD-struct or POD-union (in the
2409
    //   sense of ISO C++ [class]) with a bitfield member whose
2410
    //   declared width is wider than the declared type of the
2411
    //   bitfield is not a POD for the purpose of layout.  Similarly,
2412
    //   an array type is not a POD for the purpose of layout if the
2413
    //   element type of the array is not a POD for the purpose of
2414
    //   layout.
2415
    //
2416
    //   Where references to the ISO C++ are made in this paragraph,
2417
    //   the Technical Corrigendum 1 version of the standard is
2418
    //   intended.
2419
294k
    return RD->isPOD();
2420
2421
297
  case TargetCXXABI::UseTailPaddingUnlessPOD11:
2422
    // This is equivalent to RD->getTypeForDecl().isCXX11PODType(),
2423
    // but with a lot of abstraction penalty stripped off.  This does
2424
    // assume that these properties are set correctly even in C++98
2425
    // mode; fortunately, that is true because we want to assign
2426
    // consistently semantics to the type-traits intrinsics (or at
2427
    // least as many of them as possible).
2428
297
    return RD->isTrivial() && 
RD->isCXX11StandardLayout()94
;
2429
294k
  }
2430
2431
0
  llvm_unreachable("bad tail-padding use kind");
2432
0
}
2433
2434
417k
static bool isMsLayout(const ASTContext &Context) {
2435
417k
  return Context.getTargetInfo().getCXXABI().isMicrosoft();
2436
417k
}
2437
2438
// This section contains an implementation of struct layout that is, up to the
2439
// included tests, compatible with cl.exe (2013).  The layout produced is
2440
// significantly different than those produced by the Itanium ABI.  Here we note
2441
// the most important differences.
2442
//
2443
// * The alignment of bitfields in unions is ignored when computing the
2444
//   alignment of the union.
2445
// * The existence of zero-width bitfield that occurs after anything other than
2446
//   a non-zero length bitfield is ignored.
2447
// * There is no explicit primary base for the purposes of layout.  All bases
2448
//   with vfptrs are laid out first, followed by all bases without vfptrs.
2449
// * The Itanium equivalent vtable pointers are split into a vfptr (virtual
2450
//   function pointer) and a vbptr (virtual base pointer).  They can each be
2451
//   shared with a, non-virtual bases. These bases need not be the same.  vfptrs
2452
//   always occur at offset 0.  vbptrs can occur at an arbitrary offset and are
2453
//   placed after the lexicographically last non-virtual base.  This placement
2454
//   is always before fields but can be in the middle of the non-virtual bases
2455
//   due to the two-pass layout scheme for non-virtual-bases.
2456
// * Virtual bases sometimes require a 'vtordisp' field that is laid out before
2457
//   the virtual base and is used in conjunction with virtual overrides during
2458
//   construction and destruction.  This is always a 4 byte value and is used as
2459
//   an alternative to constructor vtables.
2460
// * vtordisps are allocated in a block of memory with size and alignment equal
2461
//   to the alignment of the completed structure (before applying __declspec(
2462
//   align())).  The vtordisp always occur at the end of the allocation block,
2463
//   immediately prior to the virtual base.
2464
// * vfptrs are injected after all bases and fields have been laid out.  In
2465
//   order to guarantee proper alignment of all fields, the vfptr injection
2466
//   pushes all bases and fields back by the alignment imposed by those bases
2467
//   and fields.  This can potentially add a significant amount of padding.
2468
//   vfptrs are always injected at offset 0.
2469
// * vbptrs are injected after all bases and fields have been laid out.  In
2470
//   order to guarantee proper alignment of all fields, the vfptr injection
2471
//   pushes all bases and fields back by the alignment imposed by those bases
2472
//   and fields.  This can potentially add a significant amount of padding.
2473
//   vbptrs are injected immediately after the last non-virtual base as
2474
//   lexicographically ordered in the code.  If this site isn't pointer aligned
2475
//   the vbptr is placed at the next properly aligned location.  Enough padding
2476
//   is added to guarantee a fit.
2477
// * The last zero sized non-virtual base can be placed at the end of the
2478
//   struct (potentially aliasing another object), or may alias with the first
2479
//   field, even if they are of the same type.
2480
// * The last zero size virtual base may be placed at the end of the struct
2481
//   potentially aliasing another object.
2482
// * The ABI attempts to avoid aliasing of zero sized bases by adding padding
2483
//   between bases or vbases with specific properties.  The criteria for
2484
//   additional padding between two bases is that the first base is zero sized
2485
//   or ends with a zero sized subobject and the second base is zero sized or
2486
//   trails with a zero sized base or field (sharing of vfptrs can reorder the
2487
//   layout of the so the leading base is not always the first one declared).
2488
//   This rule does take into account fields that are not records, so padding
2489
//   will occur even if the last field is, e.g. an int. The padding added for
2490
//   bases is 1 byte.  The padding added between vbases depends on the alignment
2491
//   of the object but is at least 4 bytes (in both 32 and 64 bit modes).
2492
// * There is no concept of non-virtual alignment, non-virtual alignment and
2493
//   alignment are always identical.
2494
// * There is a distinction between alignment and required alignment.
2495
//   __declspec(align) changes the required alignment of a struct.  This
2496
//   alignment is _always_ obeyed, even in the presence of #pragma pack. A
2497
//   record inherits required alignment from all of its fields and bases.
2498
// * __declspec(align) on bitfields has the effect of changing the bitfield's
2499
//   alignment instead of its required alignment.  This is the only known way
2500
//   to make the alignment of a struct bigger than 8.  Interestingly enough
2501
//   this alignment is also immune to the effects of #pragma pack and can be
2502
//   used to create structures with large alignment under #pragma pack.
2503
//   However, because it does not impact required alignment, such a structure,
2504
//   when used as a field or base, will not be aligned if #pragma pack is
2505
//   still active at the time of use.
2506
//
2507
// Known incompatibilities:
2508
// * all: #pragma pack between fields in a record
2509
// * 2010 and back: If the last field in a record is a bitfield, every object
2510
//   laid out after the record will have extra padding inserted before it.  The
2511
//   extra padding will have size equal to the size of the storage class of the
2512
//   bitfield.  0 sized bitfields don't exhibit this behavior and the extra
2513
//   padding can be avoided by adding a 0 sized bitfield after the non-zero-
2514
//   sized bitfield.
2515
// * 2012 and back: In 64-bit mode, if the alignment of a record is 16 or
2516
//   greater due to __declspec(align()) then a second layout phase occurs after
2517
//   The locations of the vf and vb pointers are known.  This layout phase
2518
//   suffers from the "last field is a bitfield" bug in 2010 and results in
2519
//   _every_ field getting padding put in front of it, potentially including the
2520
//   vfptr, leaving the vfprt at a non-zero location which results in a fault if
2521
//   anything tries to read the vftbl.  The second layout phase also treats
2522
//   bitfields as separate entities and gives them each storage rather than
2523
//   packing them.  Additionally, because this phase appears to perform a
2524
//   (an unstable) sort on the members before laying them out and because merged
2525
//   bitfields have the same address, the bitfields end up in whatever order
2526
//   the sort left them in, a behavior we could never hope to replicate.
2527
2528
namespace {
2529
struct MicrosoftRecordLayoutBuilder {
2530
  struct ElementInfo {
2531
    CharUnits Size;
2532
    CharUnits Alignment;
2533
  };
2534
  typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsetsMapTy;
2535
7.87k
  MicrosoftRecordLayoutBuilder(const ASTContext &Context) : Context(Context) {}
2536
private:
2537
  MicrosoftRecordLayoutBuilder(const MicrosoftRecordLayoutBuilder &) = delete;
2538
  void operator=(const MicrosoftRecordLayoutBuilder &) = delete;
2539
public:
2540
  void layout(const RecordDecl *RD);
2541
  void cxxLayout(const CXXRecordDecl *RD);
2542
  /// Initializes size and alignment and honors some flags.
2543
  void initializeLayout(const RecordDecl *RD);
2544
  /// Initialized C++ layout, compute alignment and virtual alignment and
2545
  /// existence of vfptrs and vbptrs.  Alignment is needed before the vfptr is
2546
  /// laid out.
2547
  void initializeCXXLayout(const CXXRecordDecl *RD);
2548
  void layoutNonVirtualBases(const CXXRecordDecl *RD);
2549
  void layoutNonVirtualBase(const CXXRecordDecl *RD,
2550
                            const CXXRecordDecl *BaseDecl,
2551
                            const ASTRecordLayout &BaseLayout,
2552
                            const ASTRecordLayout *&PreviousBaseLayout);
2553
  void injectVFPtr(const CXXRecordDecl *RD);
2554
  void injectVBPtr(const CXXRecordDecl *RD);
2555
  /// Lays out the fields of the record.  Also rounds size up to
2556
  /// alignment.
2557
  void layoutFields(const RecordDecl *RD);
2558
  void layoutField(const FieldDecl *FD);
2559
  void layoutBitField(const FieldDecl *FD);
2560
  /// Lays out a single zero-width bit-field in the record and handles
2561
  /// special cases associated with zero-width bit-fields.
2562
  void layoutZeroWidthBitField(const FieldDecl *FD);
2563
  void layoutVirtualBases(const CXXRecordDecl *RD);
2564
  void finalizeLayout(const RecordDecl *RD);
2565
  /// Gets the size and alignment of a base taking pragma pack and
2566
  /// __declspec(align) into account.
2567
  ElementInfo getAdjustedElementInfo(const ASTRecordLayout &Layout);
2568
  /// Gets the size and alignment of a field taking pragma  pack and
2569
  /// __declspec(align) into account.  It also updates RequiredAlignment as a
2570
  /// side effect because it is most convenient to do so here.
2571
  ElementInfo getAdjustedElementInfo(const FieldDecl *FD);
2572
  /// Places a field at an offset in CharUnits.
2573
3.27k
  void placeFieldAtOffset(CharUnits FieldOffset) {
2574
3.27k
    FieldOffsets.push_back(Context.toBits(FieldOffset));
2575
3.27k
  }
2576
  /// Places a bitfield at a bit offset.
2577
66
  void placeFieldAtBitOffset(uint64_t FieldOffset) {
2578
66
    FieldOffsets.push_back(FieldOffset);
2579
66
  }
2580
  /// Compute the set of virtual bases for which vtordisps are required.
2581
  void computeVtorDispSet(
2582
      llvm::SmallPtrSetImpl<const CXXRecordDecl *> &HasVtorDispSet,
2583
      const CXXRecordDecl *RD) const;
2584
  const ASTContext &Context;
2585
  /// The size of the record being laid out.
2586
  CharUnits Size;
2587
  /// The non-virtual size of the record layout.
2588
  CharUnits NonVirtualSize;
2589
  /// The data size of the record layout.
2590
  CharUnits DataSize;
2591
  /// The current alignment of the record layout.
2592
  CharUnits Alignment;
2593
  /// The maximum allowed field alignment. This is set by #pragma pack.
2594
  CharUnits MaxFieldAlignment;
2595
  /// The alignment that this record must obey.  This is imposed by
2596
  /// __declspec(align()) on the record itself or one of its fields or bases.
2597
  CharUnits RequiredAlignment;
2598
  /// The size of the allocation of the currently active bitfield.
2599
  /// This value isn't meaningful unless LastFieldIsNonZeroWidthBitfield
2600
  /// is true.
2601
  CharUnits CurrentBitfieldSize;
2602
  /// Offset to the virtual base table pointer (if one exists).
2603
  CharUnits VBPtrOffset;
2604
  /// Minimum record size possible.
2605
  CharUnits MinEmptyStructSize;
2606
  /// The size and alignment info of a pointer.
2607
  ElementInfo PointerInfo;
2608
  /// The primary base class (if one exists).
2609
  const CXXRecordDecl *PrimaryBase;
2610
  /// The class we share our vb-pointer with.
2611
  const CXXRecordDecl *SharedVBPtrBase;
2612
  /// The collection of field offsets.
2613
  SmallVector<uint64_t, 16> FieldOffsets;
2614
  /// Base classes and their offsets in the record.
2615
  BaseOffsetsMapTy Bases;
2616
  /// virtual base classes and their offsets in the record.
2617
  ASTRecordLayout::VBaseOffsetsMapTy VBases;
2618
  /// The number of remaining bits in our last bitfield allocation.
2619
  /// This value isn't meaningful unless LastFieldIsNonZeroWidthBitfield is
2620
  /// true.
2621
  unsigned RemainingBitsInField;
2622
  bool IsUnion : 1;
2623
  /// True if the last field laid out was a bitfield and was not 0
2624
  /// width.
2625
  bool LastFieldIsNonZeroWidthBitfield : 1;
2626
  /// True if the class has its own vftable pointer.
2627
  bool HasOwnVFPtr : 1;
2628
  /// True if the class has a vbtable pointer.
2629
  bool HasVBPtr : 1;
2630
  /// True if the last sub-object within the type is zero sized or the
2631
  /// object itself is zero sized.  This *does not* count members that are not
2632
  /// records.  Only used for MS-ABI.
2633
  bool EndsWithZeroSizedObject : 1;
2634
  /// True if this class is zero sized or first base is zero sized or
2635
  /// has this property.  Only used for MS-ABI.
2636
  bool LeadsWithZeroSizedBase : 1;
2637
2638
  /// True if the external AST source provided a layout for this record.
2639
  bool UseExternalLayout : 1;
2640
2641
  /// The layout provided by the external AST source. Only active if
2642
  /// UseExternalLayout is true.
2643
  ExternalLayout External;
2644
};
2645
} // namespace
2646
2647
MicrosoftRecordLayoutBuilder::ElementInfo
2648
MicrosoftRecordLayoutBuilder::getAdjustedElementInfo(
2649
3.14k
    const ASTRecordLayout &Layout) {
2650
3.14k
  ElementInfo Info;
2651
3.14k
  Info.Alignment = Layout.getAlignment();
2652
  // Respect pragma pack.
2653
3.14k
  if (!MaxFieldAlignment.isZero())
2654
34
    Info.Alignment = std::min(Info.Alignment, MaxFieldAlignment);
2655
  // Track zero-sized subobjects here where it's already available.
2656
3.14k
  EndsWithZeroSizedObject = Layout.endsWithZeroSizedObject();
2657
  // Respect required alignment, this is necessary because we may have adjusted
2658
  // the alignment in the case of pragma pack.  Note that the required alignment
2659
  // doesn't actually apply to the struct alignment at this point.
2660
3.14k
  Alignment = std::max(Alignment, Info.Alignment);
2661
3.14k
  RequiredAlignment = std::max(RequiredAlignment, Layout.getRequiredAlignment());
2662
3.14k
  Info.Alignment = std::max(Info.Alignment, Layout.getRequiredAlignment());
2663
3.14k
  Info.Size = Layout.getNonVirtualSize();
2664
3.14k
  return Info;
2665
3.14k
}
2666
2667
MicrosoftRecordLayoutBuilder::ElementInfo
2668
MicrosoftRecordLayoutBuilder::getAdjustedElementInfo(
2669
3.31k
    const FieldDecl *FD) {
2670
  // Get the alignment of the field type's natural alignment, ignore any
2671
  // alignment attributes.
2672
3.31k
  auto TInfo =
2673
3.31k
      Context.getTypeInfoInChars(FD->getType()->getUnqualifiedDesugaredType());
2674
3.31k
  ElementInfo Info{TInfo.Width, TInfo.Align};
2675
  // Respect align attributes on the field.
2676
3.31k
  CharUnits FieldRequiredAlignment =
2677
3.31k
      Context.toCharUnitsFromBits(FD->getMaxAlignment());
2678
  // Respect align attributes on the type.
2679
3.31k
  if (Context.isAlignmentRequired(FD->getType()))
2680
84
    FieldRequiredAlignment = std::max(
2681
84
        Context.getTypeAlignInChars(FD->getType()), FieldRequiredAlignment);
2682
  // Respect attributes applied to subobjects of the field.
2683
3.31k
  if (FD->isBitField())
2684
    // For some reason __declspec align impacts alignment rather than required
2685
    // alignment when it is applied to bitfields.
2686
230
    Info.Alignment = std::max(Info.Alignment, FieldRequiredAlignment);
2687
3.08k
  else {
2688
3.08k
    if (auto RT =
2689
3.08k
            FD->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
2690
256
      auto const &Layout = Context.getASTRecordLayout(RT->getDecl());
2691
256
      EndsWithZeroSizedObject = Layout.endsWithZeroSizedObject();
2692
256
      FieldRequiredAlignment = std::max(FieldRequiredAlignment,
2693
256
                                        Layout.getRequiredAlignment());
2694
256
    }
2695
    // Capture required alignment as a side-effect.
2696
3.08k
    RequiredAlignment = std::max(RequiredAlignment, FieldRequiredAlignment);
2697
3.08k
  }
2698
  // Respect pragma pack, attribute pack and declspec align
2699
3.31k
  if (!MaxFieldAlignment.isZero())
2700
257
    Info.Alignment = std::min(Info.Alignment, MaxFieldAlignment);
2701
3.31k
  if (FD->hasAttr<PackedAttr>())
2702
7
    Info.Alignment = CharUnits::One();
2703
3.31k
  Info.Alignment = std::max(Info.Alignment, FieldRequiredAlignment);
2704
3.31k
  return Info;
2705
3.31k
}
2706
2707
348
void MicrosoftRecordLayoutBuilder::layout(const RecordDecl *RD) {
2708
  // For C record layout, zero-sized records always have size 4.
2709
348
  MinEmptyStructSize = CharUnits::fromQuantity(4);
2710
348
  initializeLayout(RD);
2711
348
  layoutFields(RD);
2712
348
  DataSize = Size = Size.alignTo(Alignment);
2713
348
  RequiredAlignment = std::max(
2714
348
      RequiredAlignment, Context.toCharUnitsFromBits(RD->getMaxAlignment()));
2715
348
  finalizeLayout(RD);
2716
348
}
2717
2718
7.52k
void MicrosoftRecordLayoutBuilder::cxxLayout(const CXXRecordDecl *RD) {
2719
  // The C++ standard says that empty structs have size 1.
2720
7.52k
  MinEmptyStructSize = CharUnits::One();
2721
7.52k
  initializeLayout(RD);
2722
7.52k
  initializeCXXLayout(RD);
2723
7.52k
  layoutNonVirtualBases(RD);
2724
7.52k
  layoutFields(RD);
2725
7.52k
  injectVBPtr(RD);
2726
7.52k
  injectVFPtr(RD);
2727
7.52k
  if (HasOwnVFPtr || 
(6.68k
HasVBPtr6.68k
&&
!SharedVBPtrBase748
))
2728
1.38k
    Alignment = std::max(Alignment, PointerInfo.Alignment);
2729
7.52k
  auto RoundingAlignment = Alignment;
2730
7.52k
  if (!MaxFieldAlignment.isZero())
2731
56
    RoundingAlignment = std::min(RoundingAlignment, MaxFieldAlignment);
2732
7.52k
  if (!UseExternalLayout)
2733
7.51k
    Size = Size.alignTo(RoundingAlignment);
2734
7.52k
  NonVirtualSize = Size;
2735
7.52k
  RequiredAlignment = std::max(
2736
7.52k
      RequiredAlignment, Context.toCharUnitsFromBits(RD->getMaxAlignment()));
2737
7.52k
  layoutVirtualBases(RD);
2738
7.52k
  finalizeLayout(RD);
2739
7.52k
}
2740
2741
7.87k
void MicrosoftRecordLayoutBuilder::initializeLayout(const RecordDecl *RD) {
2742
7.87k
  IsUnion = RD->isUnion();
2743
7.87k
  Size = CharUnits::Zero();
2744
7.87k
  Alignment = CharUnits::One();
2745
  // In 64-bit mode we always perform an alignment step after laying out vbases.
2746
  // In 32-bit mode we do not.  The check to see if we need to perform alignment
2747
  // checks the RequiredAlignment field and performs alignment if it isn't 0.
2748
7.87k
  RequiredAlignment = Context.getTargetInfo().getTriple().isArch64Bit()
2749
7.87k
                          ? 
CharUnits::One()3.83k
2750
7.87k
                          : 
CharUnits::Zero()4.03k
;
2751
  // Compute the maximum field alignment.
2752
7.87k
  MaxFieldAlignment = CharUnits::Zero();
2753
  // Honor the default struct packing maximum alignment flag.
2754
7.87k
  if (unsigned DefaultMaxFieldAlignment = Context.getLangOpts().PackStruct)
2755
0
      MaxFieldAlignment = CharUnits::fromQuantity(DefaultMaxFieldAlignment);
2756
  // Honor the packing attribute.  The MS-ABI ignores pragma pack if its larger
2757
  // than the pointer size.
2758
7.87k
  if (const MaxFieldAlignmentAttr *MFAA = RD->getAttr<MaxFieldAlignmentAttr>()){
2759
125
    unsigned PackedAlignment = MFAA->getAlignment();
2760
125
    if (PackedAlignment <= Context.getTargetInfo().getPointerWidth(0))
2761
92
      MaxFieldAlignment = Context.toCharUnitsFromBits(PackedAlignment);
2762
125
  }
2763
  // Packed attribute forces max field alignment to be 1.
2764
7.87k
  if (RD->hasAttr<PackedAttr>())
2765
61
    MaxFieldAlignment = CharUnits::One();
2766
2767
  // Try to respect the external layout if present.
2768
7.87k
  UseExternalLayout = false;
2769
7.87k
  if (ExternalASTSource *Source = Context.getExternalSource())
2770
655
    UseExternalLayout = Source->layoutRecordType(
2771
655
        RD, External.Size, External.Align, External.FieldOffsets,
2772
655
        External.BaseOffsets, External.VirtualBaseOffsets);
2773
7.87k
}
2774
2775
void
2776
7.52k
MicrosoftRecordLayoutBuilder::initializeCXXLayout(const CXXRecordDecl *RD) {
2777
7.52k
  EndsWithZeroSizedObject = false;
2778
7.52k
  LeadsWithZeroSizedBase = false;
2779
7.52k
  HasOwnVFPtr = false;
2780
7.52k
  HasVBPtr = false;
2781
7.52k
  PrimaryBase = nullptr;
2782
7.52k
  SharedVBPtrBase = nullptr;
2783
  // Calculate pointer size and alignment.  These are used for vfptr and vbprt
2784
  // injection.
2785
7.52k
  PointerInfo.Size =
2786
7.52k
      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
2787
7.52k
  PointerInfo.Alignment =
2788
7.52k
      Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerAlign(0));
2789
  // Respect pragma pack.
2790
7.52k
  if (!MaxFieldAlignment.isZero())
2791
56
    PointerInfo.Alignment = std::min(PointerInfo.Alignment, MaxFieldAlignment);
2792
7.52k
}
2793
2794
void
2795
7.52k
MicrosoftRecordLayoutBuilder::layoutNonVirtualBases(const CXXRecordDecl *RD) {
2796
  // The MS-ABI lays out all bases that contain leading vfptrs before it lays
2797
  // out any bases that do not contain vfptrs.  We implement this as two passes
2798
  // over the bases.  This approach guarantees that the primary base is laid out
2799
  // first.  We use these passes to calculate some additional aggregated
2800
  // information about the bases, such as required alignment and the presence of
2801
  // zero sized members.
2802
7.52k
  const ASTRecordLayout *PreviousBaseLayout = nullptr;
2803
7.52k
  bool HasPolymorphicBaseClass = false;
2804
  // Iterate through the bases and lay out the non-virtual ones.
2805
7.52k
  for (const CXXBaseSpecifier &Base : RD->bases()) {
2806
2.78k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2807
2.78k
    HasPolymorphicBaseClass |= BaseDecl->isPolymorphic();
2808
2.78k
    const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
2809
    // Mark and skip virtual bases.
2810
2.78k
    if (Base.isVirtual()) {
2811
916
      HasVBPtr = true;
2812
916
      continue;
2813
916
    }
2814
    // Check for a base to share a VBPtr with.
2815
1.86k
    if (!SharedVBPtrBase && 
BaseLayout.hasVBPtr()1.74k
) {
2816
228
      SharedVBPtrBase = BaseDecl;
2817
228
      HasVBPtr = true;
2818
228
    }
2819
    // Only lay out bases with extendable VFPtrs on the first pass.
2820
1.86k
    if (!BaseLayout.hasExtendableVFPtr())
2821
1.33k
      continue;
2822
    // If we don't have a primary base, this one qualifies.
2823
534
    if (!PrimaryBase) {
2824
391
      PrimaryBase = BaseDecl;
2825
391
      LeadsWithZeroSizedBase = BaseLayout.leadsWithZeroSizedBase();
2826
391
    }
2827
    // Lay out the base.
2828
534
    layoutNonVirtualBase(RD, BaseDecl, BaseLayout, PreviousBaseLayout);
2829
534
  }
2830
  // Figure out if we need a fresh VFPtr for this class.
2831
7.52k
  if (RD->isPolymorphic()) {
2832
1.50k
    if (!HasPolymorphicBaseClass)
2833
      // This class introduces polymorphism, so we need a vftable to store the
2834
      // RTTI information.
2835
755
      HasOwnVFPtr = true;
2836
754
    else if (!PrimaryBase) {
2837
      // We have a polymorphic base class but can't extend its vftable. Add a
2838
      // new vfptr if we would use any vftable slots.
2839
1.63k
      for (CXXMethodDecl *M : RD->methods()) {
2840
1.63k
        if (MicrosoftVTableContext::hasVtableSlot(M) &&
2841
1.63k
            
M->size_overridden_methods() == 0325
) {
2842
85
          HasOwnVFPtr = true;
2843
85
          break;
2844
85
        }
2845
1.63k
      }
2846
363
    }
2847
1.50k
  }
2848
  // If we don't have a primary base then we have a leading object that could
2849
  // itself lead with a zero-sized object, something we track.
2850
7.52k
  bool CheckLeadingLayout = !PrimaryBase;
2851
  // Iterate through the bases and lay out the non-virtual ones.
2852
7.52k
  for (const CXXBaseSpecifier &Base : RD->bases()) {
2853
2.78k
    if (Base.isVirtual())
2854
916
      continue;
2855
1.86k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2856
1.86k
    const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
2857
    // Only lay out bases without extendable VFPtrs on the second pass.
2858
1.86k
    if (BaseLayout.hasExtendableVFPtr()) {
2859
534
      VBPtrOffset = Bases[BaseDecl] + BaseLayout.getNonVirtualSize();
2860
534
      continue;
2861
534
    }
2862
    // If this is the first layout, check to see if it leads with a zero sized
2863
    // object.  If it does, so do we.
2864
1.33k
    if (CheckLeadingLayout) {
2865
908
      CheckLeadingLayout = false;
2866
908
      LeadsWithZeroSizedBase = BaseLayout.leadsWithZeroSizedBase();
2867
908
    }
2868
    // Lay out the base.
2869
1.33k
    layoutNonVirtualBase(RD, BaseDecl, BaseLayout, PreviousBaseLayout);
2870
1.33k
    VBPtrOffset = Bases[BaseDecl] + BaseLayout.getNonVirtualSize();
2871
1.33k
  }
2872
  // Set our VBPtroffset if we know it at this point.
2873
7.52k
  if (!HasVBPtr)
2874
6.66k
    VBPtrOffset = CharUnits::fromQuantity(-1);
2875
861
  else if (SharedVBPtrBase) {
2876
228
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(SharedVBPtrBase);
2877
228
    VBPtrOffset = Bases[SharedVBPtrBase] + Layout.getVBPtrOffset();
2878
228
  }
2879
7.52k
}
2880
2881
6.13k
static bool recordUsesEBO(const RecordDecl *RD) {
2882
6.13k
  if (!isa<CXXRecordDecl>(RD))
2883
30
    return false;
2884
6.10k
  if (RD->hasAttr<EmptyBasesAttr>())
2885
16
    return true;
2886
6.09k
  if (auto *LVA = RD->getAttr<LayoutVersionAttr>())
2887
    // TODO: Double check with the next version of MSVC.
2888
0
    if (LVA->getVersion() <= LangOptions::MSVC2015)
2889
0
      return false;
2890
  // TODO: Some later version of MSVC will change the default behavior of the
2891
  // compiler to enable EBO by default.  When this happens, we will need an
2892
  // additional isCompatibleWithMSVC check.
2893
6.09k
  return false;
2894
6.09k
}
2895
2896
void MicrosoftRecordLayoutBuilder::layoutNonVirtualBase(
2897
    const CXXRecordDecl *RD,
2898
    const CXXRecordDecl *BaseDecl,
2899
    const ASTRecordLayout &BaseLayout,
2900
1.86k
    const ASTRecordLayout *&PreviousBaseLayout) {
2901
  // Insert padding between two bases if the left first one is zero sized or
2902
  // contains a zero sized subobject and the right is zero sized or one leads
2903
  // with a zero sized base.
2904
1.86k
  bool MDCUsesEBO = recordUsesEBO(RD);
2905
1.86k
  if (PreviousBaseLayout && 
PreviousBaseLayout->endsWithZeroSizedObject()565
&&
2906
1.86k
      
BaseLayout.leadsWithZeroSizedBase()178
&&
!MDCUsesEBO142
)
2907
140
    Size++;
2908
1.86k
  ElementInfo Info = getAdjustedElementInfo(BaseLayout);
2909
1.86k
  CharUnits BaseOffset;
2910
2911
  // Respect the external AST source base offset, if present.
2912
1.86k
  bool FoundBase = false;
2913
1.86k
  if (UseExternalLayout) {
2914
2
    FoundBase = External.getExternalNVBaseOffset(BaseDecl, BaseOffset);
2915
2
    if (FoundBase) {
2916
0
      assert(BaseOffset >= Size && "base offset already allocated");
2917
0
      Size = BaseOffset;
2918
0
    }
2919
2
  }
2920
2921
1.86k
  if (!FoundBase) {
2922
1.86k
    if (MDCUsesEBO && 
BaseDecl->isEmpty()12
) {
2923
4
      assert(BaseLayout.getNonVirtualSize() == CharUnits::Zero());
2924
0
      BaseOffset = CharUnits::Zero();
2925
1.86k
    } else {
2926
      // Otherwise, lay the base out at the end of the MDC.
2927
1.86k
      BaseOffset = Size = Size.alignTo(Info.Alignment);
2928
1.86k
    }
2929
1.86k
  }
2930
0
  Bases.insert(std::make_pair(BaseDecl, BaseOffset));
2931
1.86k
  Size += BaseLayout.getNonVirtualSize();
2932
1.86k
  PreviousBaseLayout = &BaseLayout;
2933
1.86k
}
2934
2935
7.87k
void MicrosoftRecordLayoutBuilder::layoutFields(const RecordDecl *RD) {
2936
7.87k
  LastFieldIsNonZeroWidthBitfield = false;
2937
7.87k
  for (const FieldDecl *Field : RD->fields())
2938
3.33k
    layoutField(Field);
2939
7.87k
}
2940
2941
3.33k
void MicrosoftRecordLayoutBuilder::layoutField(const FieldDecl *FD) {
2942
3.33k
  if (FD->isBitField()) {
2943
251
    layoutBitField(FD);
2944
251
    return;
2945
251
  }
2946
3.08k
  LastFieldIsNonZeroWidthBitfield = false;
2947
3.08k
  ElementInfo Info = getAdjustedElementInfo(FD);
2948
3.08k
  Alignment = std::max(Alignment, Info.Alignment);
2949
3.08k
  CharUnits FieldOffset;
2950
3.08k
  if (UseExternalLayout)
2951
6
    FieldOffset =
2952
6
        Context.toCharUnitsFromBits(External.getExternalFieldOffset(FD));
2953
3.08k
  else if (IsUnion)
2954
81
    FieldOffset = CharUnits::Zero();
2955
3.00k
  else
2956
3.00k
    FieldOffset = Size.alignTo(Info.Alignment);
2957
3.08k
  placeFieldAtOffset(FieldOffset);
2958
3.08k
  Size = std::max(Size, FieldOffset + Info.Size);
2959
3.08k
}
2960
2961
251
void MicrosoftRecordLayoutBuilder::layoutBitField(const FieldDecl *FD) {
2962
251
  unsigned Width = FD->getBitWidthValue(Context);
2963
251
  if (Width == 0) {
2964
43
    layoutZeroWidthBitField(FD);
2965
43
    return;
2966
43
  }
2967
208
  ElementInfo Info = getAdjustedElementInfo(FD);
2968
  // Clamp the bitfield to a containable size for the sake of being able
2969
  // to lay them out.  Sema will throw an error.
2970
208
  if (Width > Context.toBits(Info.Size))
2971
0
    Width = Context.toBits(Info.Size);
2972
  // Check to see if this bitfield fits into an existing allocation.  Note:
2973
  // MSVC refuses to pack bitfields of formal types with different sizes
2974
  // into the same allocation.
2975
208
  if (!UseExternalLayout && 
!IsUnion203
&&
LastFieldIsNonZeroWidthBitfield185
&&
2976
208
      
CurrentBitfieldSize == Info.Size100
&&
Width <= RemainingBitsInField91
) {
2977
61
    placeFieldAtBitOffset(Context.toBits(Size) - RemainingBitsInField);
2978
61
    RemainingBitsInField -= Width;
2979
61
    return;
2980
61
  }
2981
147
  LastFieldIsNonZeroWidthBitfield = true;
2982
147
  CurrentBitfieldSize = Info.Size;
2983
147
  if (UseExternalLayout) {
2984
5
    auto FieldBitOffset = External.getExternalFieldOffset(FD);
2985
5
    placeFieldAtBitOffset(FieldBitOffset);
2986
5
    auto NewSize = Context.toCharUnitsFromBits(
2987
5
        llvm::alignDown(FieldBitOffset, Context.toBits(Info.Alignment)) +
2988
5
        Context.toBits(Info.Size));
2989
5
    Size = std::max(Size, NewSize);
2990
5
    Alignment = std::max(Alignment, Info.Alignment);
2991
142
  } else if (IsUnion) {
2992
18
    placeFieldAtOffset(CharUnits::Zero());
2993
18
    Size = std::max(Size, Info.Size);
2994
    // TODO: Add a Sema warning that MS ignores bitfield alignment in unions.
2995
124
  } else {
2996
    // Allocate a new block of memory and place the bitfield in it.
2997
124
    CharUnits FieldOffset = Size.alignTo(Info.Alignment);
2998
124
    placeFieldAtOffset(FieldOffset);
2999
124
    Size = FieldOffset + Info.Size;
3000
124
    Alignment = std::max(Alignment, Info.Alignment);
3001
124
    RemainingBitsInField = Context.toBits(Info.Size) - Width;
3002
124
  }
3003
147
}
3004
3005
void
3006
43
MicrosoftRecordLayoutBuilder::layoutZeroWidthBitField(const FieldDecl *FD) {
3007
  // Zero-width bitfields are ignored unless they follow a non-zero-width
3008
  // bitfield.
3009
43
  if (!LastFieldIsNonZeroWidthBitfield) {
3010
21
    placeFieldAtOffset(IsUnion ? 
CharUnits::Zero()4
:
Size17
);
3011
    // TODO: Add a Sema warning that MS ignores alignment for zero
3012
    // sized bitfields that occur after zero-size bitfields or non-bitfields.
3013
21
    return;
3014
21
  }
3015
22
  LastFieldIsNonZeroWidthBitfield = false;
3016
22
  ElementInfo Info = getAdjustedElementInfo(FD);
3017
22
  if (IsUnion) {
3018
8
    placeFieldAtOffset(CharUnits::Zero());
3019
8
    Size = std::max(Size, Info.Size);
3020
    // TODO: Add a Sema warning that MS ignores bitfield alignment in unions.
3021
14
  } else {
3022
    // Round up the current record size to the field's alignment boundary.
3023
14
    CharUnits FieldOffset = Size.alignTo(Info.Alignment);
3024
14
    placeFieldAtOffset(FieldOffset);
3025
14
    Size = FieldOffset;
3026
14
    Alignment = std::max(Alignment, Info.Alignment);
3027
14
  }
3028
22
}
3029
3030
7.52k
void MicrosoftRecordLayoutBuilder::injectVBPtr(const CXXRecordDecl *RD) {
3031
7.52k
  if (!HasVBPtr || 
SharedVBPtrBase861
)
3032
6.88k
    return;
3033
  // Inject the VBPointer at the injection site.
3034
633
  CharUnits InjectionSite = VBPtrOffset;
3035
  // But before we do, make sure it's properly aligned.
3036
633
  VBPtrOffset = VBPtrOffset.alignTo(PointerInfo.Alignment);
3037
  // Determine where the first field should be laid out after the vbptr.
3038
633
  CharUnits FieldStart = VBPtrOffset + PointerInfo.Size;
3039
  // Shift everything after the vbptr down, unless we're using an external
3040
  // layout.
3041
633
  if (UseExternalLayout) {
3042
    // It is possible that there were no fields or bases located after vbptr,
3043
    // so the size was not adjusted before.
3044
2
    if (Size < FieldStart)
3045
1
      Size = FieldStart;
3046
2
    return;
3047
2
  }
3048
  // Make sure that the amount we push the fields back by is a multiple of the
3049
  // alignment.
3050
631
  CharUnits Offset = (FieldStart - InjectionSite)
3051
631
                         .alignTo(std::max(RequiredAlignment, Alignment));
3052
631
  Size += Offset;
3053
631
  for (uint64_t &FieldOffset : FieldOffsets)
3054
360
    FieldOffset += Context.toBits(Offset);
3055
631
  for (BaseOffsetsMapTy::value_type &Base : Bases)
3056
256
    if (Base.second >= InjectionSite)
3057
63
      Base.second += Offset;
3058
631
}
3059
3060
7.52k
void MicrosoftRecordLayoutBuilder::injectVFPtr(const CXXRecordDecl *RD) {
3061
7.52k
  if (!HasOwnVFPtr)
3062
6.68k
    return;
3063
  // Make sure that the amount we push the struct back by is a multiple of the
3064
  // alignment.
3065
840
  CharUnits Offset =
3066
840
      PointerInfo.Size.alignTo(std::max(RequiredAlignment, Alignment));
3067
  // Push back the vbptr, but increase the size of the object and push back
3068
  // regular fields by the offset only if not using external record layout.
3069
840
  if (HasVBPtr)
3070
113
    VBPtrOffset += Offset;
3071
3072
840
  if (UseExternalLayout) {
3073
    // The class may have no bases or fields, but still have a vfptr
3074
    // (e.g. it's an interface class). The size was not correctly set before
3075
    // in this case.
3076
2
    if (FieldOffsets.empty() && 
Bases.empty()1
)
3077
1
      Size += Offset;
3078
2
    return;
3079
2
  }
3080
3081
838
  Size += Offset;
3082
3083
  // If we're using an external layout, the fields offsets have already
3084
  // accounted for this adjustment.
3085
838
  for (uint64_t &FieldOffset : FieldOffsets)
3086
161
    FieldOffset += Context.toBits(Offset);
3087
838
  for (BaseOffsetsMapTy::value_type &Base : Bases)
3088
87
    Base.second += Offset;
3089
838
}
3090
3091
7.52k
void MicrosoftRecordLayoutBuilder::layoutVirtualBases(const CXXRecordDecl *RD) {
3092
7.52k
  if (!HasVBPtr)
3093
6.66k
    return;
3094
  // Vtordisps are always 4 bytes (even in 64-bit mode)
3095
861
  CharUnits VtorDispSize = CharUnits::fromQuantity(4);
3096
861
  CharUnits VtorDispAlignment = VtorDispSize;
3097
  // vtordisps respect pragma pack.
3098
861
  if (!MaxFieldAlignment.isZero())
3099
16
    VtorDispAlignment = std::min(VtorDispAlignment, MaxFieldAlignment);
3100
  // The alignment of the vtordisp is at least the required alignment of the
3101
  // entire record.  This requirement may be present to support vtordisp
3102
  // injection.
3103
1.28k
  for (const CXXBaseSpecifier &VBase : RD->vbases()) {
3104
1.28k
    const CXXRecordDecl *BaseDecl = VBase.getType()->getAsCXXRecordDecl();
3105
1.28k
    const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
3106
1.28k
    RequiredAlignment =
3107
1.28k
        std::max(RequiredAlignment, BaseLayout.getRequiredAlignment());
3108
1.28k
  }
3109
861
  VtorDispAlignment = std::max(VtorDispAlignment, RequiredAlignment);
3110
  // Compute the vtordisp set.
3111
861
  llvm::SmallPtrSet<const CXXRecordDecl *, 2> HasVtorDispSet;
3112
861
  computeVtorDispSet(HasVtorDispSet, RD);
3113
  // Iterate through the virtual bases and lay them out.
3114
861
  const ASTRecordLayout *PreviousBaseLayout = nullptr;
3115
1.28k
  for (const CXXBaseSpecifier &VBase : RD->vbases()) {
3116
1.28k
    const CXXRecordDecl *BaseDecl = VBase.getType()->getAsCXXRecordDecl();
3117
1.28k
    const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
3118
1.28k
    bool HasVtordisp = HasVtorDispSet.contains(BaseDecl);
3119
    // Insert padding between two bases if the left first one is zero sized or
3120
    // contains a zero sized subobject and the right is zero sized or one leads
3121
    // with a zero sized base.  The padding between virtual bases is 4
3122
    // bytes (in both 32 and 64 bits modes) and always involves rounding up to
3123
    // the required alignment, we don't know why.
3124
1.28k
    if ((PreviousBaseLayout && 
PreviousBaseLayout->endsWithZeroSizedObject()420
&&
3125
1.28k
         
BaseLayout.leadsWithZeroSizedBase()168
&&
!recordUsesEBO(RD)118
) ||
3126
1.28k
        
HasVtordisp1.16k
) {
3127
276
      Size = Size.alignTo(VtorDispAlignment) + VtorDispSize;
3128
276
      Alignment = std::max(VtorDispAlignment, Alignment);
3129
276
    }
3130
    // Insert the virtual base.
3131
1.28k
    ElementInfo Info = getAdjustedElementInfo(BaseLayout);
3132
1.28k
    CharUnits BaseOffset;
3133
3134
    // Respect the external AST source base offset, if present.
3135
1.28k
    if (UseExternalLayout) {
3136
3
      if (!External.getExternalVBaseOffset(BaseDecl, BaseOffset))
3137
3
        BaseOffset = Size;
3138
3
    } else
3139
1.27k
      BaseOffset = Size.alignTo(Info.Alignment);
3140
3141
1.28k
    assert(BaseOffset >= Size && "base offset already allocated");
3142
3143
0
    VBases.insert(std::make_pair(BaseDecl,
3144
1.28k
        ASTRecordLayout::VBaseInfo(BaseOffset, HasVtordisp)));
3145
1.28k
    Size = BaseOffset + BaseLayout.getNonVirtualSize();
3146
1.28k
    PreviousBaseLayout = &BaseLayout;
3147
1.28k
  }
3148
861
}
3149
3150
7.87k
void MicrosoftRecordLayoutBuilder::finalizeLayout(const RecordDecl *RD) {
3151
  // Respect required alignment.  Note that in 32-bit mode Required alignment
3152
  // may be 0 and cause size not to be updated.
3153
7.87k
  DataSize = Size;
3154
7.87k
  if (!RequiredAlignment.isZero()) {
3155
4.01k
    Alignment = std::max(Alignment, RequiredAlignment);
3156
4.01k
    auto RoundingAlignment = Alignment;
3157
4.01k
    if (!MaxFieldAlignment.isZero())
3158
132
      RoundingAlignment = std::min(RoundingAlignment, MaxFieldAlignment);
3159
4.01k
    RoundingAlignment = std::max(RoundingAlignment, RequiredAlignment);
3160
4.01k
    Size = Size.alignTo(RoundingAlignment);
3161
4.01k
  }
3162
7.87k
  if (Size.isZero()) {
3163
4.15k
    if (!recordUsesEBO(RD) || 
!cast<CXXRecordDecl>(RD)->isEmpty()4
) {
3164
4.15k
      EndsWithZeroSizedObject = true;
3165
4.15k
      LeadsWithZeroSizedBase = true;
3166
4.15k
    }
3167
    // Zero-sized structures have size equal to their alignment if a
3168
    // __declspec(align) came into play.
3169
4.15k
    if (RequiredAlignment >= MinEmptyStructSize)
3170
2.06k
      Size = Alignment;
3171
2.09k
    else
3172
2.09k
      Size = MinEmptyStructSize;
3173
4.15k
  }
3174
3175
7.87k
  if (UseExternalLayout) {
3176
8
    Size = Context.toCharUnitsFromBits(External.Size);
3177
8
    if (External.Align)
3178
4
      Alignment = Context.toCharUnitsFromBits(External.Align);
3179
8
  }
3180
7.87k
}
3181
3182
// Recursively walks the non-virtual bases of a class and determines if any of
3183
// them are in the bases with overridden methods set.
3184
static bool
3185
RequiresVtordisp(const llvm::SmallPtrSetImpl<const CXXRecordDecl *> &
3186
                     BasesWithOverriddenMethods,
3187
681
                 const CXXRecordDecl *RD) {
3188
681
  if (BasesWithOverriddenMethods.count(RD))
3189
94
    return true;
3190
  // If any of a virtual bases non-virtual bases (recursively) requires a
3191
  // vtordisp than so does this virtual base.
3192
587
  for (const CXXBaseSpecifier &Base : RD->bases())
3193
92
    if (!Base.isVirtual() &&
3194
92
        RequiresVtordisp(BasesWithOverriddenMethods,
3195
53
                         Base.getType()->getAsCXXRecordDecl()))
3196
19
      return true;
3197
568
  return false;
3198
587
}
3199
3200
void MicrosoftRecordLayoutBuilder::computeVtorDispSet(
3201
    llvm::SmallPtrSetImpl<const CXXRecordDecl *> &HasVtordispSet,
3202
861
    const CXXRecordDecl *RD) const {
3203
  // /vd2 or #pragma vtordisp(2): Always use vtordisps for virtual bases with
3204
  // vftables.
3205
861
  if (RD->getMSVtorDispMode() == MSVtorDispMode::ForVFTable) {
3206
25
    for (const CXXBaseSpecifier &Base : RD->vbases()) {
3207
25
      const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
3208
25
      const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
3209
25
      if (Layout.hasExtendableVFPtr())
3210
23
        HasVtordispSet.insert(BaseDecl);
3211
25
    }
3212
20
    return;
3213
20
  }
3214
3215
  // If any of our bases need a vtordisp for this type, so do we.  Check our
3216
  // direct bases for vtordisp requirements.
3217
1.53k
  
for (const CXXBaseSpecifier &Base : RD->bases())841
{
3218
1.53k
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
3219
1.53k
    const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
3220
1.53k
    for (const auto &bi : Layout.getVBaseOffsetsMap())
3221
486
      if (bi.second.hasVtorDisp())
3222
43
        HasVtordispSet.insert(bi.first);
3223
1.53k
  }
3224
  // We don't introduce any additional vtordisps if either:
3225
  // * A user declared constructor or destructor aren't declared.
3226
  // * #pragma vtordisp(0) or the /vd0 flag are in use.
3227
841
  if ((!RD->hasUserDeclaredConstructor() && 
!RD->hasUserDeclaredDestructor()483
) ||
3228
841
      
RD->getMSVtorDispMode() == MSVtorDispMode::Never427
)
3229
419
    return;
3230
  // /vd1 or #pragma vtordisp(1): Try to guess based on whether we think it's
3231
  // possible for a partially constructed object with virtual base overrides to
3232
  // escape a non-trivial constructor.
3233
422
  assert(RD->getMSVtorDispMode() == MSVtorDispMode::ForVBaseOverride);
3234
  // Compute a set of base classes which define methods we override.  A virtual
3235
  // base in this set will require a vtordisp.  A virtual base that transitively
3236
  // contains one of these bases as a non-virtual base will also require a
3237
  // vtordisp.
3238
0
  llvm::SmallPtrSet<const CXXMethodDecl *, 8> Work;
3239
422
  llvm::SmallPtrSet<const CXXRecordDecl *, 2> BasesWithOverriddenMethods;
3240
  // Seed the working set with our non-destructor, non-pure virtual methods.
3241
422
  for (const CXXMethodDecl *MD : RD->methods())
3242
2.10k
    if (MicrosoftVTableContext::hasVtableSlot(MD) &&
3243
2.10k
        
!isa<CXXDestructorDecl>(MD)265
&&
!MD->isPure()184
)
3244
182
      Work.insert(MD);
3245
733
  while (!Work.empty()) {
3246
311
    const CXXMethodDecl *MD = *Work.begin();
3247
311
    auto MethodRange = MD->overridden_methods();
3248
    // If a virtual method has no-overrides it lives in its parent's vtable.
3249
311
    if (MethodRange.begin() == MethodRange.end())
3250
195
      BasesWithOverriddenMethods.insert(MD->getParent());
3251
116
    else
3252
116
      Work.insert(MethodRange.begin(), MethodRange.end());
3253
    // We've finished processing this element, remove it from the working set.
3254
311
    Work.erase(MD);
3255
311
  }
3256
  // For each of our virtual bases, check if it is in the set of overridden
3257
  // bases or if it transitively contains a non-virtual base that is.
3258
660
  for (const CXXBaseSpecifier &Base : RD->vbases()) {
3259
660
    const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
3260
660
    if (!HasVtordispSet.count(BaseDecl) &&
3261
660
        
RequiresVtordisp(BasesWithOverriddenMethods, BaseDecl)628
)
3262
94
      HasVtordispSet.insert(BaseDecl);
3263
660
  }
3264
422
}
3265
3266
/// getASTRecordLayout - Get or compute information about the layout of the
3267
/// specified record (struct/union/class), which indicates its size and field
3268
/// position information.
3269
const ASTRecordLayout &
3270
5.72M
ASTContext::getASTRecordLayout(const RecordDecl *D) const {
3271
  // These asserts test different things.  A record has a definition
3272
  // as soon as we begin to parse the definition.  That definition is
3273
  // not a complete definition (which is what isDefinition() tests)
3274
  // until we *finish* parsing the definition.
3275
3276
5.72M
  if (D->hasExternalLexicalStorage() && 
!D->getDefinition()118k
)
3277
0
    getExternalSource()->CompleteType(const_cast<RecordDecl*>(D));
3278
3279
5.72M
  D = D->getDefinition();
3280
5.72M
  assert(D && "Cannot get layout of forward declarations!");
3281
0
  assert(!D->isInvalidDecl() && "Cannot get layout of invalid decl!");
3282
0
  assert(D->isCompleteDefinition() && "Cannot layout type before complete!");
3283
3284
  // Look up this layout, if already laid out, return what we have.
3285
  // Note that we can't save a reference to the entry because this function
3286
  // is recursive.
3287
0
  const ASTRecordLayout *Entry = ASTRecordLayouts[D];
3288
5.72M
  if (Entry) 
return *Entry5.31M
;
3289
3290
416k
  const ASTRecordLayout *NewEntry = nullptr;
3291
3292
416k
  if (isMsLayout(*this)) {
3293
7.87k
    MicrosoftRecordLayoutBuilder Builder(*this);
3294
7.87k
    if (const auto *RD = dyn_cast<CXXRecordDecl>(D)) {
3295
7.52k
      Builder.cxxLayout(RD);
3296
7.52k
      NewEntry = new (*this) ASTRecordLayout(
3297
7.52k
          *this, Builder.Size, Builder.Alignment, Builder.Alignment,
3298
7.52k
          Builder.Alignment, Builder.RequiredAlignment, Builder.HasOwnVFPtr,
3299
7.52k
          Builder.HasOwnVFPtr || 
Builder.PrimaryBase6.68k
, Builder.VBPtrOffset,
3300
7.52k
          Builder.DataSize, Builder.FieldOffsets, Builder.NonVirtualSize,
3301
7.52k
          Builder.Alignment, Builder.Alignment, CharUnits::Zero(),
3302
7.52k
          Builder.PrimaryBase, false, Builder.SharedVBPtrBase,
3303
7.52k
          Builder.EndsWithZeroSizedObject, Builder.LeadsWithZeroSizedBase,
3304
7.52k
          Builder.Bases, Builder.VBases);
3305
7.52k
    } else {
3306
348
      Builder.layout(D);
3307
348
      NewEntry = new (*this) ASTRecordLayout(
3308
348
          *this, Builder.Size, Builder.Alignment, Builder.Alignment,
3309
348
          Builder.Alignment, Builder.RequiredAlignment, Builder.Size,
3310
348
          Builder.FieldOffsets);
3311
348
    }
3312
408k
  } else {
3313
408k
    if (const auto *RD = dyn_cast<CXXRecordDecl>(D)) {
3314
294k
      EmptySubobjectMap EmptySubobjects(*this, RD);
3315
294k
      ItaniumRecordLayoutBuilder Builder(*this, &EmptySubobjects);
3316
294k
      Builder.Layout(RD);
3317
3318
      // In certain situations, we are allowed to lay out objects in the
3319
      // tail-padding of base classes.  This is ABI-dependent.
3320
      // FIXME: this should be stored in the record layout.
3321
294k
      bool skipTailPadding =
3322
294k
          mustSkipTailPadding(getTargetInfo().getCXXABI(), RD);
3323
3324
      // FIXME: This should be done in FinalizeLayout.
3325
294k
      CharUnits DataSize =
3326
294k
          skipTailPadding ? 
Builder.getSize()147k
:
Builder.getDataSize()147k
;
3327
294k
      CharUnits NonVirtualSize =
3328
294k
          skipTailPadding ? 
DataSize147k
:
Builder.NonVirtualSize147k
;
3329
294k
      NewEntry = new (*this) ASTRecordLayout(
3330
294k
          *this, Builder.getSize(), Builder.Alignment,
3331
294k
          Builder.PreferredAlignment, Builder.UnadjustedAlignment,
3332
          /*RequiredAlignment : used by MS-ABI)*/
3333
294k
          Builder.Alignment, Builder.HasOwnVFPtr, RD->isDynamicClass(),
3334
294k
          CharUnits::fromQuantity(-1), DataSize, Builder.FieldOffsets,
3335
294k
          NonVirtualSize, Builder.NonVirtualAlignment,
3336
294k
          Builder.PreferredNVAlignment,
3337
294k
          EmptySubobjects.SizeOfLargestEmptySubobject, Builder.PrimaryBase,
3338
294k
          Builder.PrimaryBaseIsVirtual, nullptr, false, false, Builder.Bases,
3339
294k
          Builder.VBases);
3340
294k
    } else {
3341
113k
      ItaniumRecordLayoutBuilder Builder(*this, /*EmptySubobjects=*/nullptr);
3342
113k
      Builder.Layout(D);
3343
3344
113k
      NewEntry = new (*this) ASTRecordLayout(
3345
113k
          *this, Builder.getSize(), Builder.Alignment,
3346
113k
          Builder.PreferredAlignment, Builder.UnadjustedAlignment,
3347
          /*RequiredAlignment : used by MS-ABI)*/
3348
113k
          Builder.Alignment, Builder.getSize(), Builder.FieldOffsets);
3349
113k
    }
3350
408k
  }
3351
3352
416k
  ASTRecordLayouts[D] = NewEntry;
3353
3354
416k
  if (getLangOpts().DumpRecordLayouts) {
3355
1.36k
    llvm::outs() << "\n*** Dumping AST Record Layout\n";
3356
1.36k
    DumpRecordLayout(D, llvm::outs(), getLangOpts().DumpRecordLayoutsSimple);
3357
1.36k
  }
3358
3359
416k
  return *NewEntry;
3360
5.72M
}
3361
3362
170k
const CXXMethodDecl *ASTContext::getCurrentKeyFunction(const CXXRecordDecl *RD) {
3363
170k
  if (!getTargetInfo().getCXXABI().hasKeyFunctions())
3364
3.38k
    return nullptr;
3365
3366
167k
  assert(RD->getDefinition() && "Cannot get key function for forward decl!");
3367
0
  RD = RD->getDefinition();
3368
3369
  // Beware:
3370
  //  1) computing the key function might trigger deserialization, which might
3371
  //     invalidate iterators into KeyFunctions
3372
  //  2) 'get' on the LazyDeclPtr might also trigger deserialization and
3373
  //     invalidate the LazyDeclPtr within the map itself
3374
167k
  LazyDeclPtr Entry = KeyFunctions[RD];
3375
167k
  const Decl *Result =
3376
167k
      Entry ? 
Entry.get(getExternalSource())21.6k
:
computeKeyFunction(*this, RD)145k
;
3377
3378
  // Store it back if it changed.
3379
167k
  if (Entry.isOffset() || Entry.isValid() != bool(Result))
3380
14.6k
    KeyFunctions[RD] = const_cast<Decl*>(Result);
3381
3382
167k
  return cast_or_null<CXXMethodDecl>(Result);
3383
170k
}
3384
3385
14
void ASTContext::setNonKeyFunction(const CXXMethodDecl *Method) {
3386
14
  assert(Method == Method->getFirstDecl() &&
3387
14
         "not working with method declaration from class definition");
3388
3389
  // Look up the cache entry.  Since we're working with the first
3390
  // declaration, its parent must be the class definition, which is
3391
  // the correct key for the KeyFunctions hash.
3392
0
  const auto &Map = KeyFunctions;
3393
14
  auto I = Map.find(Method->getParent());
3394
3395
  // If it's not cached, there's nothing to do.
3396
14
  if (I == Map.end()) 
return0
;
3397
3398
  // If it is cached, check whether it's the target method, and if so,
3399
  // remove it from the cache. Note, the call to 'get' might invalidate
3400
  // the iterator and the LazyDeclPtr object within the map.
3401
14
  LazyDeclPtr Ptr = I->second;
3402
14
  if (Ptr.get(getExternalSource()) == Method) {
3403
    // FIXME: remember that we did this for module / chained PCH state?
3404
14
    KeyFunctions.erase(Method->getParent());
3405
14
  }
3406
14
}
3407
3408
604
static uint64_t getFieldOffset(const ASTContext &C, const FieldDecl *FD) {
3409
604
  const ASTRecordLayout &Layout = C.getASTRecordLayout(FD->getParent());
3410
604
  return Layout.getFieldOffset(FD->getFieldIndex());
3411
604
}
3412
3413
564
uint64_t ASTContext::getFieldOffset(const ValueDecl *VD) const {
3414
564
  uint64_t OffsetInBits;
3415
564
  if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
3416
538
    OffsetInBits = ::getFieldOffset(*this, FD);
3417
538
  } else {
3418
26
    const IndirectFieldDecl *IFD = cast<IndirectFieldDecl>(VD);
3419
3420
26
    OffsetInBits = 0;
3421
26
    for (const NamedDecl *ND : IFD->chain())
3422
66
      OffsetInBits += ::getFieldOffset(*this, cast<FieldDecl>(ND));
3423
26
  }
3424
3425
564
  return OffsetInBits;
3426
564
}
3427
3428
uint64_t ASTContext::lookupFieldBitOffset(const ObjCInterfaceDecl *OID,
3429
                                          const ObjCImplementationDecl *ID,
3430
3.35k
                                          const ObjCIvarDecl *Ivar) const {
3431
3.35k
  Ivar = Ivar->getCanonicalDecl();
3432
3.35k
  const ObjCInterfaceDecl *Container = Ivar->getContainingInterface();
3433
3434
  // FIXME: We should eliminate the need to have ObjCImplementationDecl passed
3435
  // in here; it should never be necessary because that should be the lexical
3436
  // decl context for the ivar.
3437
3438
  // If we know have an implementation (and the ivar is in it) then
3439
  // look up in the implementation layout.
3440
3.35k
  const ASTRecordLayout *RL;
3441
3.35k
  if (ID && 
declaresSameEntity(ID->getClassInterface(), Container)2.51k
)
3442
2.45k
    RL = &getASTObjCImplementationLayout(ID);
3443
900
  else
3444
900
    RL = &getASTObjCInterfaceLayout(Container);
3445
3446
  // Compute field index.
3447
  //
3448
  // FIXME: The index here is closely tied to how ASTContext::getObjCLayout is
3449
  // implemented. This should be fixed to get the information from the layout
3450
  // directly.
3451
3.35k
  unsigned Index = 0;
3452
3453
3.35k
  for (const ObjCIvarDecl *IVD = Container->all_declared_ivar_begin();
3454
8.63k
       IVD; 
IVD = IVD->getNextIvar()5.27k
) {
3455
8.63k
    if (Ivar == IVD)
3456
3.35k
      break;
3457
5.27k
    ++Index;
3458
5.27k
  }
3459
3.35k
  assert(Index < RL->getFieldCount() && "Ivar is not inside record layout!");
3460
3461
0
  return RL->getFieldOffset(Index);
3462
3.35k
}
3463
3464
/// getObjCLayout - Get or compute information about the layout of the
3465
/// given interface.
3466
///
3467
/// \param Impl - If given, also include the layout of the interface's
3468
/// implementation. This may differ by including synthesized ivars.
3469
const ASTRecordLayout &
3470
ASTContext::getObjCLayout(const ObjCInterfaceDecl *D,
3471
18.8k
                          const ObjCImplementationDecl *Impl) const {
3472
  // Retrieve the definition
3473
18.8k
  if (D->hasExternalLexicalStorage() && 
!D->getDefinition()126
)
3474
0
    getExternalSource()->CompleteType(const_cast<ObjCInterfaceDecl*>(D));
3475
18.8k
  D = D->getDefinition();
3476
18.8k
  assert(D && !D->isInvalidDecl() && D->isThisDeclarationADefinition() &&
3477
18.8k
         "Invalid interface decl!");
3478
3479
  // Look up this layout, if already laid out, return what we have.
3480
0
  const ObjCContainerDecl *Key =
3481
18.8k
    Impl ? 
(const ObjCContainerDecl*) Impl3.58k
:
(const ObjCContainerDecl*) D15.2k
;
3482
18.8k
  if (const ASTRecordLayout *Entry = ObjCLayouts[Key])
3483
11.4k
    return *Entry;
3484
3485
  // Add in synthesized ivar count if laying out an implementation.
3486
7.41k
  if (Impl) {
3487
2.56k
    unsigned SynthCount = CountNonClassIvars(D);
3488
    // If there aren't any synthesized ivars then reuse the interface
3489
    // entry. Note we can't cache this because we simply free all
3490
    // entries later; however we shouldn't look up implementations
3491
    // frequently.
3492
2.56k
    if (SynthCount == 0)
3493
2.32k
      return getObjCLayout(D, nullptr);
3494
2.56k
  }
3495
3496
5.09k
  ItaniumRecordLayoutBuilder Builder(*this, /*EmptySubobjects=*/nullptr);
3497
5.09k
  Builder.Layout(D);
3498
3499
5.09k
  const ASTRecordLayout *NewEntry = new (*this) ASTRecordLayout(
3500
5.09k
      *this, Builder.getSize(), Builder.Alignment, Builder.PreferredAlignment,
3501
5.09k
      Builder.UnadjustedAlignment,
3502
      /*RequiredAlignment : used by MS-ABI)*/
3503
5.09k
      Builder.Alignment, Builder.getDataSize(), Builder.FieldOffsets);
3504
3505
5.09k
  ObjCLayouts[Key] = NewEntry;
3506
3507
5.09k
  return *NewEntry;
3508
7.41k
}
3509
3510
static void PrintOffset(raw_ostream &OS,
3511
5.54k
                        CharUnits Offset, unsigned IndentLevel) {
3512
5.54k
  OS << llvm::format("%10" PRId64 " | ", (int64_t)Offset.getQuantity());
3513
5.54k
  OS.indent(IndentLevel * 2);
3514
5.54k
}
3515
3516
static void PrintBitFieldOffset(raw_ostream &OS, CharUnits Offset,
3517
                                unsigned Begin, unsigned Width,
3518
552
                                unsigned IndentLevel) {
3519
552
  llvm::SmallString<10> Buffer;
3520
552
  {
3521
552
    llvm::raw_svector_ostream BufferOS(Buffer);
3522
552
    BufferOS << Offset.getQuantity() << ':';
3523
552
    if (Width == 0) {
3524
108
      BufferOS << '-';
3525
444
    } else {
3526
444
      BufferOS << Begin << '-' << (Begin + Width - 1);
3527
444
    }
3528
552
  }
3529
3530
552
  OS << llvm::right_justify(Buffer, 10) << " | ";
3531
552
  OS.indent(IndentLevel * 2);
3532
552
}
3533
3534
2.40k
static void PrintIndentNoOffset(raw_ostream &OS, unsigned IndentLevel) {
3535
2.40k
  OS << "           | ";
3536
2.40k
  OS.indent(IndentLevel * 2);
3537
2.40k
}
3538
3539
static void DumpRecordLayout(raw_ostream &OS, const RecordDecl *RD,
3540
                             const ASTContext &C,
3541
                             CharUnits Offset,
3542
                             unsigned IndentLevel,
3543
                             const char* Description,
3544
                             bool PrintSizeInfo,
3545
2.86k
                             bool IncludeVirtualBases) {
3546
2.86k
  const ASTRecordLayout &Layout = C.getASTRecordLayout(RD);
3547
2.86k
  auto CXXRD = dyn_cast<CXXRecordDecl>(RD);
3548
3549
2.86k
  PrintOffset(OS, Offset, IndentLevel);
3550
2.86k
  OS << C.getTypeDeclType(const_cast<RecordDecl *>(RD));
3551
2.86k
  if (Description)
3552
1.58k
    OS << ' ' << Description;
3553
2.86k
  if (CXXRD && 
CXXRD->isEmpty()2.70k
)
3554
817
    OS << " (empty)";
3555
2.86k
  OS << '\n';
3556
3557
2.86k
  IndentLevel++;
3558
3559
  // Dump bases.
3560
2.86k
  if (CXXRD) {
3561
2.70k
    const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
3562
2.70k
    bool HasOwnVFPtr = Layout.hasOwnVFPtr();
3563
2.70k
    bool HasOwnVBPtr = Layout.hasOwnVBPtr();
3564
3565
    // Vtable pointer.
3566
2.70k
    if (CXXRD->isDynamicClass() && 
!PrimaryBase793
&&
!isMsLayout(C)736
) {
3567
17
      PrintOffset(OS, Offset, IndentLevel);
3568
17
      OS << '(' << *RD << " vtable pointer)\n";
3569
2.68k
    } else if (HasOwnVFPtr) {
3570
345
      PrintOffset(OS, Offset, IndentLevel);
3571
      // vfptr (for Microsoft C++ ABI)
3572
345
      OS << '(' << *RD << " vftable pointer)\n";
3573
345
    }
3574
3575
    // Collect nvbases.
3576
2.70k
    SmallVector<const CXXRecordDecl *, 4> Bases;
3577
2.70k
    for (const CXXBaseSpecifier &Base : CXXRD->bases()) {
3578
1.40k
      assert(!Base.getType()->isDependentType() &&
3579
1.40k
             "Cannot layout class with dependent bases.");
3580
1.40k
      if (!Base.isVirtual())
3581
773
        Bases.push_back(Base.getType()->getAsCXXRecordDecl());
3582
1.40k
    }
3583
3584
    // Sort nvbases by offset.
3585
2.70k
    llvm::stable_sort(
3586
2.70k
        Bases, [&](const CXXRecordDecl *L, const CXXRecordDecl *R) {
3587
312
          return Layout.getBaseClassOffset(L) < Layout.getBaseClassOffset(R);
3588
312
        });
3589
3590
    // Dump (non-virtual) bases
3591
2.70k
    for (const CXXRecordDecl *Base : Bases) {
3592
773
      CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base);
3593
773
      DumpRecordLayout(OS, Base, C, BaseOffset, IndentLevel,
3594
773
                       Base == PrimaryBase ? 
"(primary base)"57
:
"(base)"716
,
3595
773
                       /*PrintSizeInfo=*/false,
3596
773
                       /*IncludeVirtualBases=*/false);
3597
773
    }
3598
3599
    // vbptr (for Microsoft C++ ABI)
3600
2.70k
    if (HasOwnVBPtr) {
3601
406
      PrintOffset(OS, Offset + Layout.getVBPtrOffset(), IndentLevel);
3602
406
      OS << '(' << *RD << " vbtable pointer)\n";
3603
406
    }
3604
2.70k
  }
3605
3606
  // Dump fields.
3607
2.86k
  uint64_t FieldNo = 0;
3608
2.86k
  for (RecordDecl::field_iterator I = RD->field_begin(),
3609
5.43k
         E = RD->field_end(); I != E; 
++I, ++FieldNo2.57k
) {
3610
2.57k
    const FieldDecl &Field = **I;
3611
2.57k
    uint64_t LocalFieldOffsetInBits = Layout.getFieldOffset(FieldNo);
3612
2.57k
    CharUnits FieldOffset =
3613
2.57k
      Offset + C.toCharUnitsFromBits(LocalFieldOffsetInBits);
3614
3615
    // Recursively dump fields of record type.
3616
2.57k
    if (auto RT = Field.getType()->getAs<RecordType>()) {
3617
189
      DumpRecordLayout(OS, RT->getDecl(), C, FieldOffset, IndentLevel,
3618
189
                       Field.getName().data(),
3619
189
                       /*PrintSizeInfo=*/false,
3620
189
                       /*IncludeVirtualBases=*/true);
3621
189
      continue;
3622
189
    }
3623
3624
2.38k
    if (Field.isBitField()) {
3625
552
      uint64_t LocalFieldByteOffsetInBits = C.toBits(FieldOffset - Offset);
3626
552
      unsigned Begin = LocalFieldOffsetInBits - LocalFieldByteOffsetInBits;
3627
552
      unsigned Width = Field.getBitWidthValue(C);
3628
552
      PrintBitFieldOffset(OS, FieldOffset, Begin, Width, IndentLevel);
3629
1.83k
    } else {
3630
1.83k
      PrintOffset(OS, FieldOffset, IndentLevel);
3631
1.83k
    }
3632
2.38k
    const QualType &FieldType = C.getLangOpts().DumpRecordLayoutsCanonical
3633
2.38k
                                    ? 
Field.getType().getCanonicalType()2
3634
2.38k
                                    : 
Field.getType()2.38k
;
3635
2.38k
    OS << FieldType << ' ' << Field << '\n';
3636
2.38k
  }
3637
3638
  // Dump virtual bases.
3639
2.86k
  if (CXXRD && 
IncludeVirtualBases2.70k
) {
3640
1.31k
    const ASTRecordLayout::VBaseOffsetsMapTy &VtorDisps =
3641
1.31k
      Layout.getVBaseOffsetsMap();
3642
3643
1.31k
    for (const CXXBaseSpecifier &Base : CXXRD->vbases()) {
3644
620
      assert(Base.isVirtual() && "Found non-virtual class!");
3645
0
      const CXXRecordDecl *VBase = Base.getType()->getAsCXXRecordDecl();
3646
3647
620
      CharUnits VBaseOffset = Offset + Layout.getVBaseClassOffset(VBase);
3648
3649
620
      if (VtorDisps.find(VBase)->second.hasVtorDisp()) {
3650
74
        PrintOffset(OS, VBaseOffset - CharUnits::fromQuantity(4), IndentLevel);
3651
74
        OS << "(vtordisp for vbase " << *VBase << ")\n";
3652
74
      }
3653
3654
620
      DumpRecordLayout(OS, VBase, C, VBaseOffset, IndentLevel,
3655
620
                       VBase == Layout.getPrimaryBase() ?
3656
620
                         
"(primary virtual base)"0
: "(virtual base)",
3657
620
                       /*PrintSizeInfo=*/false,
3658
620
                       /*IncludeVirtualBases=*/false);
3659
620
    }
3660
1.31k
  }
3661
3662
2.86k
  if (!PrintSizeInfo) 
return1.58k
;
3663
3664
1.28k
  PrintIndentNoOffset(OS, IndentLevel - 1);
3665
1.28k
  OS << "[sizeof=" << Layout.getSize().getQuantity();
3666
1.28k
  if (CXXRD && 
!isMsLayout(C)1.12k
)
3667
256
    OS << ", dsize=" << Layout.getDataSize().getQuantity();
3668
1.28k
  OS << ", align=" << Layout.getAlignment().getQuantity();
3669
1.28k
  if (C.getTargetInfo().defaultsToAIXPowerAlignment())
3670
252
    OS << ", preferredalign=" << Layout.getPreferredAlignment().getQuantity();
3671
3672
1.28k
  if (CXXRD) {
3673
1.12k
    OS << ",\n";
3674
1.12k
    PrintIndentNoOffset(OS, IndentLevel - 1);
3675
1.12k
    OS << " nvsize=" << Layout.getNonVirtualSize().getQuantity();
3676
1.12k
    OS << ", nvalign=" << Layout.getNonVirtualAlignment().getQuantity();
3677
1.12k
    if (C.getTargetInfo().defaultsToAIXPowerAlignment())
3678
204
      OS << ", preferrednvalign="
3679
204
         << Layout.getPreferredNVAlignment().getQuantity();
3680
1.12k
  }
3681
1.28k
  OS << "]\n";
3682
1.28k
}
3683
3684
void ASTContext::DumpRecordLayout(const RecordDecl *RD, raw_ostream &OS,
3685
1.36k
                                  bool Simple) const {
3686
1.36k
  if (!Simple) {
3687
1.28k
    ::DumpRecordLayout(OS, RD, *this, CharUnits(), 0, nullptr,
3688
1.28k
                       /*PrintSizeInfo*/ true,
3689
1.28k
                       /*IncludeVirtualBases=*/true);
3690
1.28k
    return;
3691
1.28k
  }
3692
3693
  // The "simple" format is designed to be parsed by the
3694
  // layout-override testing code.  There shouldn't be any external
3695
  // uses of this format --- when LLDB overrides a layout, it sets up
3696
  // the data structures directly --- so feel free to adjust this as
3697
  // you like as long as you also update the rudimentary parser for it
3698
  // in libFrontend.
3699
3700
83
  const ASTRecordLayout &Info = getASTRecordLayout(RD);
3701
83
  OS << "Type: " << getTypeDeclType(RD) << "\n";
3702
83
  OS << "\nLayout: ";
3703
83
  OS << "<ASTRecordLayout\n";
3704
83
  OS << "  Size:" << toBits(Info.getSize()) << "\n";
3705
83
  if (!isMsLayout(*this))
3706
72
    OS << "  DataSize:" << toBits(Info.getDataSize()) << "\n";
3707
83
  OS << "  Alignment:" << toBits(Info.getAlignment()) << "\n";
3708
83
  if (Target->defaultsToAIXPowerAlignment())
3709
0
    OS << "  PreferredAlignment:" << toBits(Info.getPreferredAlignment())
3710
0
       << "\n";
3711
83
  OS << "  FieldOffsets: [";
3712
270
  for (unsigned i = 0, e = Info.getFieldCount(); i != e; 
++i187
) {
3713
187
    if (i)
3714
111
      OS << ", ";
3715
187
    OS << Info.getFieldOffset(i);
3716
187
  }
3717
83
  OS << "]>\n";
3718
83
}