RecordLayoutBuilder.cpp source code [clang_source_code/lib/AST/RecordLayoutBuilder.cpp]

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/RecordLayout.h"
10	#include "clang/AST/ASTContext.h"
11	#include "clang/AST/ASTDiagnostic.h"
12	#include "clang/AST/Attr.h"
13	#include "clang/AST/CXXInheritance.h"
14	#include "clang/AST/Decl.h"
15	#include "clang/AST/DeclCXX.h"
16	#include "clang/AST/DeclObjC.h"
17	#include "clang/AST/Expr.h"
18	#include "clang/Basic/TargetInfo.h"
19	#include "llvm/ADT/SmallSet.h"
20	#include "llvm/Support/Format.h"
21	#include "llvm/Support/MathExtras.h"
22
23	using namespace clang;
24
25	namespace {
26
27	/// BaseSubobjectInfo - Represents a single base subobject in a complete class.
28	/// For a class hierarchy like
29	///
30	/// class A { };
31	/// class B : A { };
32	/// class C : A, B { };
33	///
34	/// The BaseSubobjectInfo graph for C will have three BaseSubobjectInfo
35	/// instances, one for B and two for A.
36	///
37	/// If a base is virtual, it will only have one BaseSubobjectInfo allocated.
38	struct BaseSubobjectInfo {
39	/// Class - The class for this base info.
40	const CXXRecordDecl *Class;
41
42	/// IsVirtual - Whether the BaseInfo represents a virtual base or not.
43	bool IsVirtual;
44
45	/// Bases - Information about the base subobjects.
46	SmallVector<BaseSubobjectInfo*, 4> Bases;
47
48	/// PrimaryVirtualBaseInfo - Holds the base info for the primary virtual base
49	/// of this base info (if one exists).
50	BaseSubobjectInfo *PrimaryVirtualBaseInfo;
51
52	// FIXME: Document.
53	const BaseSubobjectInfo *Derived;
54	};
55
56	/// Externally provided layout. Typically used when the AST source, such
57	/// as DWARF, lacks all the information that was available at compile time, such
58	/// as alignment attributes on fields and pragmas in effect.
59	struct ExternalLayout {
60	ExternalLayout() : Size(0), Align(0) {}
61
62	/// Overall record size in bits.
63	uint64_t Size;
64
65	/// Overall record alignment in bits.
66	uint64_t Align;
67
68	/// Record field offsets in bits.
69	llvm::DenseMap<const FieldDecl *, uint64_t> FieldOffsets;
70
71	/// Direct, non-virtual base offsets.
72	llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsets;
73
74	/// Virtual base offsets.
75	llvm::DenseMap<const CXXRecordDecl *, CharUnits> VirtualBaseOffsets;
76
77	/// Get the offset of the given field. The external source must provide
78	/// entries for all fields in the record.
79	uint64_t getExternalFieldOffset(const FieldDecl *FD) {
80	(0) . __assert_fail ("FieldOffsets.count(FD) && \"Field does not have an external offset\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 81, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(FieldOffsets.count(FD) &&
81	(0) . __assert_fail ("FieldOffsets.count(FD) && \"Field does not have an external offset\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 81, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Field does not have an external offset");
82	return FieldOffsets[FD];
83	}
84
85	bool getExternalNVBaseOffset(const CXXRecordDecl *RD, CharUnits &BaseOffset) {
86	auto Known = BaseOffsets.find(RD);
87	if (Known == BaseOffsets.end())
88	return false;
89	BaseOffset = Known->second;
90	return true;
91	}
92
93	bool getExternalVBaseOffset(const CXXRecordDecl *RD, CharUnits &BaseOffset) {
94	auto Known = VirtualBaseOffsets.find(RD);
95	if (Known == VirtualBaseOffsets.end())
96	return false;
97	BaseOffset = Known->second;
98	return true;
99	}
100	};
101
102	/// EmptySubobjectMap - Keeps track of which empty subobjects exist at different
103	/// offsets while laying out a C++ class.
104	class EmptySubobjectMap {
105	const ASTContext &Context;
106	uint64_t CharWidth;
107
108	/// Class - The class whose empty entries we're keeping track of.
109	const CXXRecordDecl *Class;
110
111	/// EmptyClassOffsets - A map from offsets to empty record decls.
112	typedef llvm::TinyPtrVector<const CXXRecordDecl *> ClassVectorTy;
113	typedef llvm::DenseMap<CharUnits, ClassVectorTy> EmptyClassOffsetsMapTy;
114	EmptyClassOffsetsMapTy EmptyClassOffsets;
115
116	/// MaxEmptyClassOffset - The highest offset known to contain an empty
117	/// base subobject.
118	CharUnits MaxEmptyClassOffset;
119
120	/// ComputeEmptySubobjectSizes - Compute the size of the largest base or
121	/// member subobject that is empty.
122	void ComputeEmptySubobjectSizes();
123
124	void AddSubobjectAtOffset(const CXXRecordDecl *RD, CharUnits Offset);
125
126	void UpdateEmptyBaseSubobjects(const BaseSubobjectInfo *Info,
127	CharUnits Offset, bool PlacingEmptyBase);
128
129	void UpdateEmptyFieldSubobjects(const CXXRecordDecl *RD,
130	const CXXRecordDecl *Class,
131	CharUnits Offset);
132	void UpdateEmptyFieldSubobjects(const FieldDecl *FD, CharUnits Offset);
133
134	/// AnyEmptySubobjectsBeyondOffset - Returns whether there are any empty
135	/// subobjects beyond the given offset.
136	bool AnyEmptySubobjectsBeyondOffset(CharUnits Offset) const {
137	return Offset <= MaxEmptyClassOffset;
138	}
139
140	CharUnits
141	getFieldOffset(const ASTRecordLayout &Layout, unsigned FieldNo) const {
142	uint64_t FieldOffset = Layout.getFieldOffset(FieldNo);
143	(0) . __assert_fail ("FieldOffset % CharWidth == 0 && \"Field offset not at char boundary!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 144, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(FieldOffset % CharWidth == 0 &&
144	(0) . __assert_fail ("FieldOffset % CharWidth == 0 && \"Field offset not at char boundary!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 144, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Field offset not at char boundary!");
145
146	return Context.toCharUnitsFromBits(FieldOffset);
147	}
148
149	protected:
150	bool CanPlaceSubobjectAtOffset(const CXXRecordDecl *RD,
151	CharUnits Offset) const;
152
153	bool CanPlaceBaseSubobjectAtOffset(const BaseSubobjectInfo *Info,
154	CharUnits Offset);
155
156	bool CanPlaceFieldSubobjectAtOffset(const CXXRecordDecl *RD,
157	const CXXRecordDecl *Class,
158	CharUnits Offset) const;
159	bool CanPlaceFieldSubobjectAtOffset(const FieldDecl *FD,
160	CharUnits Offset) const;
161
162	public:
163	/// This holds the size of the largest empty subobject (either a base
164	/// or a member). Will be zero if the record being built doesn't contain
165	/// any empty classes.
166	CharUnits SizeOfLargestEmptySubobject;
167
168	EmptySubobjectMap(const ASTContext &Context, const CXXRecordDecl *Class)
169	: Context(Context), CharWidth(Context.getCharWidth()), Class(Class) {
170	ComputeEmptySubobjectSizes();
171	}
172
173	/// CanPlaceBaseAtOffset - Return whether the given base class can be placed
174	/// at the given offset.
175	/// Returns false if placing the record will result in two components
176	/// (direct or indirect) of the same type having the same offset.
177	bool CanPlaceBaseAtOffset(const BaseSubobjectInfo *Info,
178	CharUnits Offset);
179
180	/// CanPlaceFieldAtOffset - Return whether a field can be placed at the given
181	/// offset.
182	bool CanPlaceFieldAtOffset(const FieldDecl *FD, CharUnits Offset);
183	};
184
185	void EmptySubobjectMap::ComputeEmptySubobjectSizes() {
186	// Check the bases.
187	for (const CXXBaseSpecifier &Base : Class->bases()) {
188	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
189
190	CharUnits EmptySize;
191	const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
192	if (BaseDecl->isEmpty()) {
193	// If the class decl is empty, get its size.
194	EmptySize = Layout.getSize();
195	} else {
196	// Otherwise, we get the largest empty subobject for the decl.
197	EmptySize = Layout.getSizeOfLargestEmptySubobject();
198	}
199
200	if (EmptySize > SizeOfLargestEmptySubobject)
201	SizeOfLargestEmptySubobject = EmptySize;
202	}
203
204	// Check the fields.
205	for (const FieldDecl *FD : Class->fields()) {
206	const RecordType *RT =
207	Context.getBaseElementType(FD->getType())->getAs<RecordType>();
208
209	// We only care about record types.
210	if (!RT)
211	continue;
212
213	CharUnits EmptySize;
214	const CXXRecordDecl *MemberDecl = RT->getAsCXXRecordDecl();
215	const ASTRecordLayout &Layout = Context.getASTRecordLayout(MemberDecl);
216	if (MemberDecl->isEmpty()) {
217	// If the class decl is empty, get its size.
218	EmptySize = Layout.getSize();
219	} else {
220	// Otherwise, we get the largest empty subobject for the decl.
221	EmptySize = Layout.getSizeOfLargestEmptySubobject();
222	}
223
224	if (EmptySize > SizeOfLargestEmptySubobject)
225	SizeOfLargestEmptySubobject = EmptySize;
226	}
227	}
228
229	bool
230	EmptySubobjectMap::CanPlaceSubobjectAtOffset(const CXXRecordDecl *RD,
231	CharUnits Offset) const {
232	// We only need to check empty bases.
233	if (!RD->isEmpty())
234	return true;
235
236	EmptyClassOffsetsMapTy::const_iterator I = EmptyClassOffsets.find(Offset);
237	if (I == EmptyClassOffsets.end())
238	return true;
239
240	const ClassVectorTy &Classes = I->second;
241	if (std::find(Classes.begin(), Classes.end(), RD) == Classes.end())
242	return true;
243
244	// There is already an empty class of the same type at this offset.
245	return false;
246	}
247
248	void EmptySubobjectMap::AddSubobjectAtOffset(const CXXRecordDecl *RD,
249	CharUnits Offset) {
250	// We only care about empty bases.
251	if (!RD->isEmpty())
252	return;
253
254	// If we have empty structures inside a union, we can assign both
255	// the same offset. Just avoid pushing them twice in the list.
256	ClassVectorTy &Classes = EmptyClassOffsets[Offset];
257	if (llvm::is_contained(Classes, RD))
258	return;
259
260	Classes.push_back(RD);
261
262	// Update the empty class offset.
263	if (Offset > MaxEmptyClassOffset)
264	MaxEmptyClassOffset = Offset;
265	}
266
267	bool
268	EmptySubobjectMap::CanPlaceBaseSubobjectAtOffset(const BaseSubobjectInfo *Info,
269	CharUnits Offset) {
270	// We don't have to keep looking past the maximum offset that's known to
271	// contain an empty class.
272	if (!AnyEmptySubobjectsBeyondOffset(Offset))
273	return true;
274
275	if (!CanPlaceSubobjectAtOffset(Info->Class, Offset))
276	return false;
277
278	// Traverse all non-virtual bases.
279	const ASTRecordLayout &Layout = Context.getASTRecordLayout(Info->Class);
280	for (const BaseSubobjectInfo *Base : Info->Bases) {
281	if (Base->IsVirtual)
282	continue;
283
284	CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base->Class);
285
286	if (!CanPlaceBaseSubobjectAtOffset(Base, BaseOffset))
287	return false;
288	}
289
290	if (Info->PrimaryVirtualBaseInfo) {
291	BaseSubobjectInfo *PrimaryVirtualBaseInfo = Info->PrimaryVirtualBaseInfo;
292
293	if (Info == PrimaryVirtualBaseInfo->Derived) {
294	if (!CanPlaceBaseSubobjectAtOffset(PrimaryVirtualBaseInfo, Offset))
295	return false;
296	}
297	}
298
299	// Traverse all member variables.
300	unsigned FieldNo = 0;
301	for (CXXRecordDecl::field_iterator I = Info->Class->field_begin(),
302	E = Info->Class->field_end(); I != E; ++I, ++FieldNo) {
303	if (I->isBitField())
304	continue;
305
306	CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
307	if (!CanPlaceFieldSubobjectAtOffset(*I, FieldOffset))
308	return false;
309	}
310
311	return true;
312	}
313
314	void EmptySubobjectMap::UpdateEmptyBaseSubobjects(const BaseSubobjectInfo *Info,
315	CharUnits Offset,
316	bool PlacingEmptyBase) {
317	if (!PlacingEmptyBase && Offset >= SizeOfLargestEmptySubobject) {
318	// We know that the only empty subobjects that can conflict with empty
319	// subobject of non-empty bases, are empty bases that can be placed at
320	// offset zero. Because of this, we only need to keep track of empty base
321	// subobjects with offsets less than the size of the largest empty
322	// subobject for our class.
323	return;
324	}
325
326	AddSubobjectAtOffset(Info->Class, Offset);
327
328	// Traverse all non-virtual bases.
329	const ASTRecordLayout &Layout = Context.getASTRecordLayout(Info->Class);
330	for (const BaseSubobjectInfo *Base : Info->Bases) {
331	if (Base->IsVirtual)
332	continue;
333
334	CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base->Class);
335	UpdateEmptyBaseSubobjects(Base, BaseOffset, PlacingEmptyBase);
336	}
337
338	if (Info->PrimaryVirtualBaseInfo) {
339	BaseSubobjectInfo *PrimaryVirtualBaseInfo = Info->PrimaryVirtualBaseInfo;
340
341	if (Info == PrimaryVirtualBaseInfo->Derived)
342	UpdateEmptyBaseSubobjects(PrimaryVirtualBaseInfo, Offset,
343	PlacingEmptyBase);
344	}
345
346	// Traverse all member variables.
347	unsigned FieldNo = 0;
348	for (CXXRecordDecl::field_iterator I = Info->Class->field_begin(),
349	E = Info->Class->field_end(); I != E; ++I, ++FieldNo) {
350	if (I->isBitField())
351	continue;
352
353	CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
354	UpdateEmptyFieldSubobjects(*I, FieldOffset);
355	}
356	}
357
358	bool EmptySubobjectMap::CanPlaceBaseAtOffset(const BaseSubobjectInfo *Info,
359	CharUnits Offset) {
360	// If we know this class doesn't have any empty subobjects we don't need to
361	// bother checking.
362	if (SizeOfLargestEmptySubobject.isZero())
363	return true;
364
365	if (!CanPlaceBaseSubobjectAtOffset(Info, Offset))
366	return false;
367
368	// We are able to place the base at this offset. Make sure to update the
369	// empty base subobject map.
370	UpdateEmptyBaseSubobjects(Info, Offset, Info->Class->isEmpty());
371	return true;
372	}
373
374	bool
375	EmptySubobjectMap::CanPlaceFieldSubobjectAtOffset(const CXXRecordDecl *RD,
376	const CXXRecordDecl *Class,
377	CharUnits Offset) const {
378	// We don't have to keep looking past the maximum offset that's known to
379	// contain an empty class.
380	if (!AnyEmptySubobjectsBeyondOffset(Offset))
381	return true;
382
383	if (!CanPlaceSubobjectAtOffset(RD, Offset))
384	return false;
385
386	const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
387
388	// Traverse all non-virtual bases.
389	for (const CXXBaseSpecifier &Base : RD->bases()) {
390	if (Base.isVirtual())
391	continue;
392
393	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
394
395	CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(BaseDecl);
396	if (!CanPlaceFieldSubobjectAtOffset(BaseDecl, Class, BaseOffset))
397	return false;
398	}
399
400	if (RD == Class) {
401	// This is the most derived class, traverse virtual bases as well.
402	for (const CXXBaseSpecifier &Base : RD->vbases()) {
403	const CXXRecordDecl *VBaseDecl = Base.getType()->getAsCXXRecordDecl();
404
405	CharUnits VBaseOffset = Offset + Layout.getVBaseClassOffset(VBaseDecl);
406	if (!CanPlaceFieldSubobjectAtOffset(VBaseDecl, Class, VBaseOffset))
407	return false;
408	}
409	}
410
411	// Traverse all member variables.
412	unsigned FieldNo = 0;
413	for (CXXRecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
414	I != E; ++I, ++FieldNo) {
415	if (I->isBitField())
416	continue;
417
418	CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
419
420	if (!CanPlaceFieldSubobjectAtOffset(*I, FieldOffset))
421	return false;
422	}
423
424	return true;
425	}
426
427	bool
428	EmptySubobjectMap::CanPlaceFieldSubobjectAtOffset(const FieldDecl *FD,
429	CharUnits Offset) const {
430	// We don't have to keep looking past the maximum offset that's known to
431	// contain an empty class.
432	if (!AnyEmptySubobjectsBeyondOffset(Offset))
433	return true;
434
435	QualType T = FD->getType();
436	if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
437	return CanPlaceFieldSubobjectAtOffset(RD, RD, Offset);
438
439	// If we have an array type we need to look at every element.
440	if (const ConstantArrayType *AT = Context.getAsConstantArrayType(T)) {
441	QualType ElemTy = Context.getBaseElementType(AT);
442	const RecordType *RT = ElemTy->getAs<RecordType>();
443	if (!RT)
444	return true;
445
446	const CXXRecordDecl *RD = RT->getAsCXXRecordDecl();
447	const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
448
449	uint64_t NumElements = Context.getConstantArrayElementCount(AT);
450	CharUnits ElementOffset = Offset;
451	for (uint64_t I = 0; I != NumElements; ++I) {
452	// We don't have to keep looking past the maximum offset that's known to
453	// contain an empty class.
454	if (!AnyEmptySubobjectsBeyondOffset(ElementOffset))
455	return true;
456
457	if (!CanPlaceFieldSubobjectAtOffset(RD, RD, ElementOffset))
458	return false;
459
460	ElementOffset += Layout.getSize();
461	}
462	}
463
464	return true;
465	}
466
467	bool
468	EmptySubobjectMap::CanPlaceFieldAtOffset(const FieldDecl *FD,
469	CharUnits Offset) {
470	if (!CanPlaceFieldSubobjectAtOffset(FD, Offset))
471	return false;
472
473	// We are able to place the member variable at this offset.
474	// Make sure to update the empty base subobject map.
475	UpdateEmptyFieldSubobjects(FD, Offset);
476	return true;
477	}
478
479	void EmptySubobjectMap::UpdateEmptyFieldSubobjects(const CXXRecordDecl *RD,
480	const CXXRecordDecl *Class,
481	CharUnits Offset) {
482	// We know that the only empty subobjects that can conflict with empty
483	// field subobjects are subobjects of empty bases that can be placed at offset
484	// zero. Because of this, we only need to keep track of empty field
485	// subobjects with offsets less than the size of the largest empty
486	// subobject for our class.
487	if (Offset >= SizeOfLargestEmptySubobject)
488	return;
489
490	AddSubobjectAtOffset(RD, Offset);
491
492	const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
493
494	// Traverse all non-virtual bases.
495	for (const CXXBaseSpecifier &Base : RD->bases()) {
496	if (Base.isVirtual())
497	continue;
498
499	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
500
501	CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(BaseDecl);
502	UpdateEmptyFieldSubobjects(BaseDecl, Class, BaseOffset);
503	}
504
505	if (RD == Class) {
506	// This is the most derived class, traverse virtual bases as well.
507	for (const CXXBaseSpecifier &Base : RD->vbases()) {
508	const CXXRecordDecl *VBaseDecl = Base.getType()->getAsCXXRecordDecl();
509
510	CharUnits VBaseOffset = Offset + Layout.getVBaseClassOffset(VBaseDecl);
511	UpdateEmptyFieldSubobjects(VBaseDecl, Class, VBaseOffset);
512	}
513	}
514
515	// Traverse all member variables.
516	unsigned FieldNo = 0;
517	for (CXXRecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
518	I != E; ++I, ++FieldNo) {
519	if (I->isBitField())
520	continue;
521
522	CharUnits FieldOffset = Offset + getFieldOffset(Layout, FieldNo);
523
524	UpdateEmptyFieldSubobjects(*I, FieldOffset);
525	}
526	}
527
528	void EmptySubobjectMap::UpdateEmptyFieldSubobjects(const FieldDecl *FD,
529	CharUnits Offset) {
530	QualType T = FD->getType();
531	if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
532	UpdateEmptyFieldSubobjects(RD, RD, Offset);
533	return;
534	}
535
536	// If we have an array type we need to update every element.
537	if (const ConstantArrayType *AT = Context.getAsConstantArrayType(T)) {
538	QualType ElemTy = Context.getBaseElementType(AT);
539	const RecordType *RT = ElemTy->getAs<RecordType>();
540	if (!RT)
541	return;
542
543	const CXXRecordDecl *RD = RT->getAsCXXRecordDecl();
544	const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
545
546	uint64_t NumElements = Context.getConstantArrayElementCount(AT);
547	CharUnits ElementOffset = Offset;
548
549	for (uint64_t I = 0; I != NumElements; ++I) {
550	// We know that the only empty subobjects that can conflict with empty
551	// field subobjects are subobjects of empty bases that can be placed at
552	// offset zero. Because of this, we only need to keep track of empty field
553	// subobjects with offsets less than the size of the largest empty
554	// subobject for our class.
555	if (ElementOffset >= SizeOfLargestEmptySubobject)
556	return;
557
558	UpdateEmptyFieldSubobjects(RD, RD, ElementOffset);
559	ElementOffset += Layout.getSize();
560	}
561	}
562	}
563
564	typedef llvm::SmallPtrSet<const CXXRecordDecl*, 4> ClassSetTy;
565
566	class ItaniumRecordLayoutBuilder {
567	protected:
568	// FIXME: Remove this and make the appropriate fields public.
569	friend class clang::ASTContext;
570
571	const ASTContext &Context;
572
573	EmptySubobjectMap *EmptySubobjects;
574
575	/// Size - The current size of the record layout.
576	uint64_t Size;
577
578	/// Alignment - The current alignment of the record layout.
579	CharUnits Alignment;
580
581	/// The alignment if attribute packed is not used.
582	CharUnits UnpackedAlignment;
583
584	/// \brief The maximum of the alignments of top-level members.
585	CharUnits UnadjustedAlignment;
586
587	SmallVector<uint64_t, 16> FieldOffsets;
588
589	/// Whether the external AST source has provided a layout for this
590	/// record.
591	unsigned UseExternalLayout : 1;
592
593	/// Whether we need to infer alignment, even when we have an
594	/// externally-provided layout.
595	unsigned InferAlignment : 1;
596
597	/// Packed - Whether the record is packed or not.
598	unsigned Packed : 1;
599
600	unsigned IsUnion : 1;
601
602	unsigned IsMac68kAlign : 1;
603
604	unsigned IsMsStruct : 1;
605
606	/// UnfilledBitsInLastUnit - If the last field laid out was a bitfield,
607	/// this contains the number of bits in the last unit that can be used for
608	/// an adjacent bitfield if necessary. The unit in question is usually
609	/// a byte, but larger units are used if IsMsStruct.
610	unsigned char UnfilledBitsInLastUnit;
611	/// LastBitfieldTypeSize - If IsMsStruct, represents the size of the type
612	/// of the previous field if it was a bitfield.
613	unsigned char LastBitfieldTypeSize;
614
615	/// MaxFieldAlignment - The maximum allowed field alignment. This is set by
616	/// #pragma pack.
617	CharUnits MaxFieldAlignment;
618
619	/// DataSize - The data size of the record being laid out.
620	uint64_t DataSize;
621
622	CharUnits NonVirtualSize;
623	CharUnits NonVirtualAlignment;
624
625	/// PrimaryBase - the primary base class (if one exists) of the class
626	/// we're laying out.
627	const CXXRecordDecl *PrimaryBase;
628
629	/// PrimaryBaseIsVirtual - Whether the primary base of the class we're laying
630	/// out is virtual.
631	bool PrimaryBaseIsVirtual;
632
633	/// HasOwnVFPtr - Whether the class provides its own vtable/vftbl
634	/// pointer, as opposed to inheriting one from a primary base class.
635	bool HasOwnVFPtr;
636
637	/// the flag of field offset changing due to packed attribute.
638	bool HasPackedField;
639
640	typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsetsMapTy;
641
642	/// Bases - base classes and their offsets in the record.
643	BaseOffsetsMapTy Bases;
644
645	// VBases - virtual base classes and their offsets in the record.
646	ASTRecordLayout::VBaseOffsetsMapTy VBases;
647
648	/// IndirectPrimaryBases - Virtual base classes, direct or indirect, that are
649	/// primary base classes for some other direct or indirect base class.
650	CXXIndirectPrimaryBaseSet IndirectPrimaryBases;
651
652	/// FirstNearlyEmptyVBase - The first nearly empty virtual base class in
653	/// inheritance graph order. Used for determining the primary base class.
654	const CXXRecordDecl *FirstNearlyEmptyVBase;
655
656	/// VisitedVirtualBases - A set of all the visited virtual bases, used to
657	/// avoid visiting virtual bases more than once.
658	llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBases;
659
660	/// Valid if UseExternalLayout is true.
661	ExternalLayout External;
662
663	ItaniumRecordLayoutBuilder(const ASTContext &Context,
664	EmptySubobjectMap *EmptySubobjects)
665	: Context(Context), EmptySubobjects(EmptySubobjects), Size(0),
666	Alignment(CharUnits::One()), UnpackedAlignment(CharUnits::One()),
667	UnadjustedAlignment(CharUnits::One()),
668	UseExternalLayout(false), InferAlignment(false), Packed(false),
669	IsUnion(false), IsMac68kAlign(false), IsMsStruct(false),
670	UnfilledBitsInLastUnit(0), LastBitfieldTypeSize(0),
671	MaxFieldAlignment(CharUnits::Zero()), DataSize(0),
672	NonVirtualSize(CharUnits::Zero()),
673	NonVirtualAlignment(CharUnits::One()), PrimaryBase(nullptr),
674	PrimaryBaseIsVirtual(false), HasOwnVFPtr(false),
675	HasPackedField(false), FirstNearlyEmptyVBase(nullptr) {}
676
677	void Layout(const RecordDecl *D);
678	void Layout(const CXXRecordDecl *D);
679	void Layout(const ObjCInterfaceDecl *D);
680
681	void LayoutFields(const RecordDecl *D);
682	void LayoutField(const FieldDecl *D, bool InsertExtraPadding);
683	void LayoutWideBitField(uint64_t FieldSize, uint64_t TypeSize,
684	bool FieldPacked, const FieldDecl *D);
685	void LayoutBitField(const FieldDecl *D);
686
687	TargetCXXABI getCXXABI() const {
688	return Context.getTargetInfo().getCXXABI();
689	}
690
691	/// BaseSubobjectInfoAllocator - Allocator for BaseSubobjectInfo objects.
692	llvm::SpecificBumpPtrAllocator<BaseSubobjectInfo> BaseSubobjectInfoAllocator;
693
694	typedef llvm::DenseMap<const CXXRecordDecl , BaseSubobjectInfo >
695	BaseSubobjectInfoMapTy;
696
697	/// VirtualBaseInfo - Map from all the (direct or indirect) virtual bases
698	/// of the class we're laying out to their base subobject info.
699	BaseSubobjectInfoMapTy VirtualBaseInfo;
700
701	/// NonVirtualBaseInfo - Map from all the direct non-virtual bases of the
702	/// class we're laying out to their base subobject info.
703	BaseSubobjectInfoMapTy NonVirtualBaseInfo;
704
705	/// ComputeBaseSubobjectInfo - Compute the base subobject information for the
706	/// bases of the given class.
707	void ComputeBaseSubobjectInfo(const CXXRecordDecl *RD);
708
709	/// ComputeBaseSubobjectInfo - Compute the base subobject information for a
710	/// single class and all of its base classes.
711	BaseSubobjectInfo ComputeBaseSubobjectInfo(const CXXRecordDecl RD,
712	bool IsVirtual,
713	BaseSubobjectInfo *Derived);
714
715	/// DeterminePrimaryBase - Determine the primary base of the given class.
716	void DeterminePrimaryBase(const CXXRecordDecl *RD);
717
718	void SelectPrimaryVBase(const CXXRecordDecl *RD);
719
720	void EnsureVTablePointerAlignment(CharUnits UnpackedBaseAlign);
721
722	/// LayoutNonVirtualBases - Determines the primary base class (if any) and
723	/// lays it out. Will then proceed to lay out all non-virtual base clasess.
724	void LayoutNonVirtualBases(const CXXRecordDecl *RD);
725
726	/// LayoutNonVirtualBase - Lays out a single non-virtual base.
727	void LayoutNonVirtualBase(const BaseSubobjectInfo *Base);
728
729	void AddPrimaryVirtualBaseOffsets(const BaseSubobjectInfo *Info,
730	CharUnits Offset);
731
732	/// LayoutVirtualBases - Lays out all the virtual bases.
733	void LayoutVirtualBases(const CXXRecordDecl *RD,
734	const CXXRecordDecl *MostDerivedClass);
735
736	/// LayoutVirtualBase - Lays out a single virtual base.
737	void LayoutVirtualBase(const BaseSubobjectInfo *Base);
738
739	/// LayoutBase - Will lay out a base and return the offset where it was
740	/// placed, in chars.
741	CharUnits LayoutBase(const BaseSubobjectInfo *Base);
742
743	/// InitializeLayout - Initialize record layout for the given record decl.
744	void InitializeLayout(const Decl *D);
745
746	/// FinishLayout - Finalize record layout. Adjust record size based on the
747	/// alignment.
748	void FinishLayout(const NamedDecl *D);
749
750	void UpdateAlignment(CharUnits NewAlignment, CharUnits UnpackedNewAlignment);
751	void UpdateAlignment(CharUnits NewAlignment) {
752	UpdateAlignment(NewAlignment, NewAlignment);
753	}
754
755	/// Retrieve the externally-supplied field offset for the given
756	/// field.
757	///
758	/// \param Field The field whose offset is being queried.
759	/// \param ComputedOffset The offset that we've computed for this field.
760	uint64_t updateExternalFieldOffset(const FieldDecl *Field,
761	uint64_t ComputedOffset);
762
763	void CheckFieldPadding(uint64_t Offset, uint64_t UnpaddedOffset,
764	uint64_t UnpackedOffset, unsigned UnpackedAlign,
765	bool isPacked, const FieldDecl *D);
766
767	DiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID);
768
769	CharUnits getSize() const {
770	assert(Size % Context.getCharWidth() == 0);
771	return Context.toCharUnitsFromBits(Size);
772	}
773	uint64_t getSizeInBits() const { return Size; }
774
775	void setSize(CharUnits NewSize) { Size = Context.toBits(NewSize); }
776	void setSize(uint64_t NewSize) { Size = NewSize; }
777
778	CharUnits getAligment() const { return Alignment; }
779
780	CharUnits getDataSize() const {
781	assert(DataSize % Context.getCharWidth() == 0);
782	return Context.toCharUnitsFromBits(DataSize);
783	}
784	uint64_t getDataSizeInBits() const { return DataSize; }
785
786	void setDataSize(CharUnits NewSize) { DataSize = Context.toBits(NewSize); }
787	void setDataSize(uint64_t NewSize) { DataSize = NewSize; }
788
789	ItaniumRecordLayoutBuilder(const ItaniumRecordLayoutBuilder &) = delete;
790	void operator=(const ItaniumRecordLayoutBuilder &) = delete;
791	};
792	} // end anonymous namespace
793
794	void ItaniumRecordLayoutBuilder::SelectPrimaryVBase(const CXXRecordDecl *RD) {
795	for (const auto &I : RD->bases()) {
796	(0) . __assert_fail ("!I.getType()->isDependentType() && \"Cannot layout class with dependent bases.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 797, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!I.getType()->isDependentType() &&
797	(0) . __assert_fail ("!I.getType()->isDependentType() && \"Cannot layout class with dependent bases.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 797, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Cannot layout class with dependent bases.");
798
799	const CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
800
801	// Check if this is a nearly empty virtual base.
802	if (I.isVirtual() && Context.isNearlyEmpty(Base)) {
803	// If it's not an indirect primary base, then we've found our primary
804	// base.
805	if (!IndirectPrimaryBases.count(Base)) {
806	PrimaryBase = Base;
807	PrimaryBaseIsVirtual = true;
808	return;
809	}
810
811	// Is this the first nearly empty virtual base?
812	if (!FirstNearlyEmptyVBase)
813	FirstNearlyEmptyVBase = Base;
814	}
815
816	SelectPrimaryVBase(Base);
817	if (PrimaryBase)
818	return;
819	}
820	}
821
822	/// DeterminePrimaryBase - Determine the primary base of the given class.
823	void ItaniumRecordLayoutBuilder::DeterminePrimaryBase(const CXXRecordDecl *RD) {
824	// If the class isn't dynamic, it won't have a primary base.
825	if (!RD->isDynamicClass())
826	return;
827
828	// Compute all the primary virtual bases for all of our direct and
829	// indirect bases, and record all their primary virtual base classes.
830	RD->getIndirectPrimaryBases(IndirectPrimaryBases);
831
832	// If the record has a dynamic base class, attempt to choose a primary base
833	// class. It is the first (in direct base class order) non-virtual dynamic
834	// base class, if one exists.
835	for (const auto &I : RD->bases()) {
836	// Ignore virtual bases.
837	if (I.isVirtual())
838	continue;
839
840	const CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
841
842	if (Base->isDynamicClass()) {
843	// We found it.
844	PrimaryBase = Base;
845	PrimaryBaseIsVirtual = false;
846	return;
847	}
848	}
849
850	// Under the Itanium ABI, if there is no non-virtual primary base class,
851	// try to compute the primary virtual base. The primary virtual base is
852	// the first nearly empty virtual base that is not an indirect primary
853	// virtual base class, if one exists.
854	if (RD->getNumVBases() != 0) {
855	SelectPrimaryVBase(RD);
856	if (PrimaryBase)
857	return;
858	}
859
860	// Otherwise, it is the first indirect primary base class, if one exists.
861	if (FirstNearlyEmptyVBase) {
862	PrimaryBase = FirstNearlyEmptyVBase;
863	PrimaryBaseIsVirtual = true;
864	return;
865	}
866
867	(0) . __assert_fail ("!PrimaryBase && \"Should not get here with a primary base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 867, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!PrimaryBase && "Should not get here with a primary base!");
868	}
869
870	BaseSubobjectInfo *ItaniumRecordLayoutBuilder::ComputeBaseSubobjectInfo(
871	const CXXRecordDecl RD, bool IsVirtual, BaseSubobjectInfo Derived) {
872	BaseSubobjectInfo *Info;
873
874	if (IsVirtual) {
875	// Check if we already have info about this virtual base.
876	BaseSubobjectInfo *&InfoSlot = VirtualBaseInfo[RD];
877	if (InfoSlot) {
878	(0) . __assert_fail ("InfoSlot->Class == RD && \"Wrong class for virtual base info!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 878, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(InfoSlot->Class == RD && "Wrong class for virtual base info!");
879	return InfoSlot;
880	}
881
882	// We don't, create it.
883	InfoSlot = new (BaseSubobjectInfoAllocator.Allocate()) BaseSubobjectInfo;
884	Info = InfoSlot;
885	} else {
886	Info = new (BaseSubobjectInfoAllocator.Allocate()) BaseSubobjectInfo;
887	}
888
889	Info->Class = RD;
890	Info->IsVirtual = IsVirtual;
891	Info->Derived = nullptr;
892	Info->PrimaryVirtualBaseInfo = nullptr;
893
894	const CXXRecordDecl *PrimaryVirtualBase = nullptr;
895	BaseSubobjectInfo *PrimaryVirtualBaseInfo = nullptr;
896
897	// Check if this base has a primary virtual base.
898	if (RD->getNumVBases()) {
899	const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
900	if (Layout.isPrimaryBaseVirtual()) {
901	// This base does have a primary virtual base.
902	PrimaryVirtualBase = Layout.getPrimaryBase();
903	(0) . __assert_fail ("PrimaryVirtualBase && \"Didn't have a primary virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 903, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(PrimaryVirtualBase && "Didn't have a primary virtual base!");
904
905	// Now check if we have base subobject info about this primary base.
906	PrimaryVirtualBaseInfo = VirtualBaseInfo.lookup(PrimaryVirtualBase);
907
908	if (PrimaryVirtualBaseInfo) {
909	if (PrimaryVirtualBaseInfo->Derived) {
910	// We did have info about this primary base, and it turns out that it
911	// has already been claimed as a primary virtual base for another
912	// base.
913	PrimaryVirtualBase = nullptr;
914	} else {
915	// We can claim this base as our primary base.
916	Info->PrimaryVirtualBaseInfo = PrimaryVirtualBaseInfo;
917	PrimaryVirtualBaseInfo->Derived = Info;
918	}
919	}
920	}
921	}
922
923	// Now go through all direct bases.
924	for (const auto &I : RD->bases()) {
925	bool IsVirtual = I.isVirtual();
926
927	const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
928
929	Info->Bases.push_back(ComputeBaseSubobjectInfo(BaseDecl, IsVirtual, Info));
930	}
931
932	if (PrimaryVirtualBase && !PrimaryVirtualBaseInfo) {
933	// Traversing the bases must have created the base info for our primary
934	// virtual base.
935	PrimaryVirtualBaseInfo = VirtualBaseInfo.lookup(PrimaryVirtualBase);
936	(0) . __assert_fail ("PrimaryVirtualBaseInfo && \"Did not create a primary virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 937, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(PrimaryVirtualBaseInfo &&
937	(0) . __assert_fail ("PrimaryVirtualBaseInfo && \"Did not create a primary virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 937, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Did not create a primary virtual base!");
938
939	// Claim the primary virtual base as our primary virtual base.
940	Info->PrimaryVirtualBaseInfo = PrimaryVirtualBaseInfo;
941	PrimaryVirtualBaseInfo->Derived = Info;
942	}
943
944	return Info;
945	}
946
947	void ItaniumRecordLayoutBuilder::ComputeBaseSubobjectInfo(
948	const CXXRecordDecl *RD) {
949	for (const auto &I : RD->bases()) {
950	bool IsVirtual = I.isVirtual();
951
952	const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
953
954	// Compute the base subobject info for this base.
955	BaseSubobjectInfo *Info = ComputeBaseSubobjectInfo(BaseDecl, IsVirtual,
956	nullptr);
957
958	if (IsVirtual) {
959	// ComputeBaseInfo has already added this base for us.
960	(0) . __assert_fail ("VirtualBaseInfo.count(BaseDecl) && \"Did not add virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 961, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(VirtualBaseInfo.count(BaseDecl) &&
961	(0) . __assert_fail ("VirtualBaseInfo.count(BaseDecl) && \"Did not add virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 961, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Did not add virtual base!");
962	} else {
963	// Add the base info to the map of non-virtual bases.
964	(0) . __assert_fail ("!NonVirtualBaseInfo.count(BaseDecl) && \"Non-virtual base already exists!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 965, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!NonVirtualBaseInfo.count(BaseDecl) &&
965	(0) . __assert_fail ("!NonVirtualBaseInfo.count(BaseDecl) && \"Non-virtual base already exists!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 965, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Non-virtual base already exists!");
966	NonVirtualBaseInfo.insert(std::make_pair(BaseDecl, Info));
967	}
968	}
969	}
970
971	void ItaniumRecordLayoutBuilder::EnsureVTablePointerAlignment(
972	CharUnits UnpackedBaseAlign) {
973	CharUnits BaseAlign = Packed ? CharUnits::One() : UnpackedBaseAlign;
974
975	// The maximum field alignment overrides base align.
976	if (!MaxFieldAlignment.isZero()) {
977	BaseAlign = std::min(BaseAlign, MaxFieldAlignment);
978	UnpackedBaseAlign = std::min(UnpackedBaseAlign, MaxFieldAlignment);
979	}
980
981	// Round up the current record size to pointer alignment.
982	setSize(getSize().alignTo(BaseAlign));
983	setDataSize(getSize());
984
985	// Update the alignment.
986	UpdateAlignment(BaseAlign, UnpackedBaseAlign);
987	}
988
989	void ItaniumRecordLayoutBuilder::LayoutNonVirtualBases(
990	const CXXRecordDecl *RD) {
991	// Then, determine the primary base class.
992	DeterminePrimaryBase(RD);
993
994	// Compute base subobject info.
995	ComputeBaseSubobjectInfo(RD);
996
997	// If we have a primary base class, lay it out.
998	if (PrimaryBase) {
999	if (PrimaryBaseIsVirtual) {
1000	// If the primary virtual base was a primary virtual base of some other
1001	// base class we'll have to steal it.
1002	BaseSubobjectInfo *PrimaryBaseInfo = VirtualBaseInfo.lookup(PrimaryBase);
1003	PrimaryBaseInfo->Derived = nullptr;
1004
1005	// We have a virtual primary base, insert it as an indirect primary base.
1006	IndirectPrimaryBases.insert(PrimaryBase);
1007
1008	(0) . __assert_fail ("!VisitedVirtualBases.count(PrimaryBase) && \"vbase already visited!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1009, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!VisitedVirtualBases.count(PrimaryBase) &&
1009	(0) . __assert_fail ("!VisitedVirtualBases.count(PrimaryBase) && \"vbase already visited!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1009, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "vbase already visited!");
1010	VisitedVirtualBases.insert(PrimaryBase);
1011
1012	LayoutVirtualBase(PrimaryBaseInfo);
1013	} else {
1014	BaseSubobjectInfo *PrimaryBaseInfo =
1015	NonVirtualBaseInfo.lookup(PrimaryBase);
1016	(0) . __assert_fail ("PrimaryBaseInfo && \"Did not find base info for non-virtual primary base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1017, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(PrimaryBaseInfo &&
1017	(0) . __assert_fail ("PrimaryBaseInfo && \"Did not find base info for non-virtual primary base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1017, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Did not find base info for non-virtual primary base!");
1018
1019	LayoutNonVirtualBase(PrimaryBaseInfo);
1020	}
1021
1022	// If this class needs a vtable/vf-table and didn't get one from a
1023	// primary base, add it in now.
1024	} else if (RD->isDynamicClass()) {
1025	(0) . __assert_fail ("DataSize == 0 && \"Vtable pointer must be at offset zero!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1025, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(DataSize == 0 && "Vtable pointer must be at offset zero!");
1026	CharUnits PtrWidth =
1027	Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
1028	CharUnits PtrAlign =
1029	Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerAlign(0));
1030	EnsureVTablePointerAlignment(PtrAlign);
1031	HasOwnVFPtr = true;
1032	setSize(getSize() + PtrWidth);
1033	setDataSize(getSize());
1034	}
1035
1036	// Now lay out the non-virtual bases.
1037	for (const auto &I : RD->bases()) {
1038
1039	// Ignore virtual bases.
1040	if (I.isVirtual())
1041	continue;
1042
1043	const CXXRecordDecl *BaseDecl = I.getType()->getAsCXXRecordDecl();
1044
1045	// Skip the primary base, because we've already laid it out. The
1046	// !PrimaryBaseIsVirtual check is required because we might have a
1047	// non-virtual base of the same type as a primary virtual base.
1048	if (BaseDecl == PrimaryBase && !PrimaryBaseIsVirtual)
1049	continue;
1050
1051	// Lay out the base.
1052	BaseSubobjectInfo *BaseInfo = NonVirtualBaseInfo.lookup(BaseDecl);
1053	(0) . __assert_fail ("BaseInfo && \"Did not find base info for non-virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1053, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseInfo && "Did not find base info for non-virtual base!");
1054
1055	LayoutNonVirtualBase(BaseInfo);
1056	}
1057	}
1058
1059	void ItaniumRecordLayoutBuilder::LayoutNonVirtualBase(
1060	const BaseSubobjectInfo *Base) {
1061	// Layout the base.
1062	CharUnits Offset = LayoutBase(Base);
1063
1064	// Add its base class offset.
1065	(0) . __assert_fail ("!Bases.count(Base->Class) && \"base offset already exists!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1065, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Bases.count(Base->Class) && "base offset already exists!");
1066	Bases.insert(std::make_pair(Base->Class, Offset));
1067
1068	AddPrimaryVirtualBaseOffsets(Base, Offset);
1069	}
1070
1071	void ItaniumRecordLayoutBuilder::AddPrimaryVirtualBaseOffsets(
1072	const BaseSubobjectInfo *Info, CharUnits Offset) {
1073	// This base isn't interesting, it has no virtual bases.
1074	if (!Info->Class->getNumVBases())
1075	return;
1076
1077	// First, check if we have a virtual primary base to add offsets for.
1078	if (Info->PrimaryVirtualBaseInfo) {
1079	(0) . __assert_fail ("Info->PrimaryVirtualBaseInfo->IsVirtual && \"Primary virtual base is not virtual!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1080, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Info->PrimaryVirtualBaseInfo->IsVirtual &&
1080	(0) . __assert_fail ("Info->PrimaryVirtualBaseInfo->IsVirtual && \"Primary virtual base is not virtual!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1080, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Primary virtual base is not virtual!");
1081	if (Info->PrimaryVirtualBaseInfo->Derived == Info) {
1082	// Add the offset.
1083	(0) . __assert_fail ("!VBases.count(Info->PrimaryVirtualBaseInfo->Class) && \"primary vbase offset already exists!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1084, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!VBases.count(Info->PrimaryVirtualBaseInfo->Class) &&
1084	(0) . __assert_fail ("!VBases.count(Info->PrimaryVirtualBaseInfo->Class) && \"primary vbase offset already exists!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1084, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "primary vbase offset already exists!");
1085	VBases.insert(std::make_pair(Info->PrimaryVirtualBaseInfo->Class,
1086	ASTRecordLayout::VBaseInfo(Offset, false)));
1087
1088	// Traverse the primary virtual base.
1089	AddPrimaryVirtualBaseOffsets(Info->PrimaryVirtualBaseInfo, Offset);
1090	}
1091	}
1092
1093	// Now go through all direct non-virtual bases.
1094	const ASTRecordLayout &Layout = Context.getASTRecordLayout(Info->Class);
1095	for (const BaseSubobjectInfo *Base : Info->Bases) {
1096	if (Base->IsVirtual)
1097	continue;
1098
1099	CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base->Class);
1100	AddPrimaryVirtualBaseOffsets(Base, BaseOffset);
1101	}
1102	}
1103
1104	void ItaniumRecordLayoutBuilder::LayoutVirtualBases(
1105	const CXXRecordDecl RD, const CXXRecordDecl MostDerivedClass) {
1106	const CXXRecordDecl *PrimaryBase;
1107	bool PrimaryBaseIsVirtual;
1108
1109	if (MostDerivedClass == RD) {
1110	PrimaryBase = this->PrimaryBase;
1111	PrimaryBaseIsVirtual = this->PrimaryBaseIsVirtual;
1112	} else {
1113	const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
1114	PrimaryBase = Layout.getPrimaryBase();
1115	PrimaryBaseIsVirtual = Layout.isPrimaryBaseVirtual();
1116	}
1117
1118	for (const CXXBaseSpecifier &Base : RD->bases()) {
1119	(0) . __assert_fail ("!Base.getType()->isDependentType() && \"Cannot layout class with dependent bases.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1120, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Base.getType()->isDependentType() &&
1120	(0) . __assert_fail ("!Base.getType()->isDependentType() && \"Cannot layout class with dependent bases.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1120, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Cannot layout class with dependent bases.");
1121
1122	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
1123
1124	if (Base.isVirtual()) {
1125	if (PrimaryBase != BaseDecl \|\| !PrimaryBaseIsVirtual) {
1126	bool IndirectPrimaryBase = IndirectPrimaryBases.count(BaseDecl);
1127
1128	// Only lay out the virtual base if it's not an indirect primary base.
1129	if (!IndirectPrimaryBase) {
1130	// Only visit virtual bases once.
1131	if (!VisitedVirtualBases.insert(BaseDecl).second)
1132	continue;
1133
1134	const BaseSubobjectInfo *BaseInfo = VirtualBaseInfo.lookup(BaseDecl);
1135	(0) . __assert_fail ("BaseInfo && \"Did not find virtual base info!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1135, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseInfo && "Did not find virtual base info!");
1136	LayoutVirtualBase(BaseInfo);
1137	}
1138	}
1139	}
1140
1141	if (!BaseDecl->getNumVBases()) {
1142	// This base isn't interesting since it doesn't have any virtual bases.
1143	continue;
1144	}
1145
1146	LayoutVirtualBases(BaseDecl, MostDerivedClass);
1147	}
1148	}
1149
1150	void ItaniumRecordLayoutBuilder::LayoutVirtualBase(
1151	const BaseSubobjectInfo *Base) {
1152	(0) . __assert_fail ("!Base->Derived && \"Trying to lay out a primary virtual base!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1152, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Base->Derived && "Trying to lay out a primary virtual base!");
1153
1154	// Layout the base.
1155	CharUnits Offset = LayoutBase(Base);
1156
1157	// Add its base class offset.
1158	(0) . __assert_fail ("!VBases.count(Base->Class) && \"vbase offset already exists!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1158, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!VBases.count(Base->Class) && "vbase offset already exists!");
1159	VBases.insert(std::make_pair(Base->Class,
1160	ASTRecordLayout::VBaseInfo(Offset, false)));
1161
1162	AddPrimaryVirtualBaseOffsets(Base, Offset);
1163	}
1164
1165	CharUnits
1166	ItaniumRecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) {
1167	const ASTRecordLayout &Layout = Context.getASTRecordLayout(Base->Class);
1168
1169
1170	CharUnits Offset;
1171
1172	// Query the external layout to see if it provides an offset.
1173	bool HasExternalLayout = false;
1174	if (UseExternalLayout) {
1175	if (Base->IsVirtual)
1176	HasExternalLayout = External.getExternalNVBaseOffset(Base->Class, Offset);
1177	else
1178	HasExternalLayout = External.getExternalVBaseOffset(Base->Class, Offset);
1179	}
1180
1181	// Clang <= 6 incorrectly applied the 'packed' attribute to base classes.
1182	// Per GCC's documentation, it only applies to non-static data members.
1183	CharUnits UnpackedBaseAlign = Layout.getNonVirtualAlignment();
1184	CharUnits BaseAlign =
1185	(Packed && ((Context.getLangOpts().getClangABICompat() <=
1186	LangOptions::ClangABI::Ver6) \|\|
1187	Context.getTargetInfo().getTriple().isPS4()))
1188	? CharUnits::One()
1189	: UnpackedBaseAlign;
1190
1191	// If we have an empty base class, try to place it at offset 0.
1192	if (Base->Class->isEmpty() &&
1193	(!HasExternalLayout \|\| Offset == CharUnits::Zero()) &&
1194	EmptySubobjects->CanPlaceBaseAtOffset(Base, CharUnits::Zero())) {
1195	setSize(std::max(getSize(), Layout.getSize()));
1196	UpdateAlignment(BaseAlign, UnpackedBaseAlign);
1197
1198	return CharUnits::Zero();
1199	}
1200
1201	// The maximum field alignment overrides base align.
1202	if (!MaxFieldAlignment.isZero()) {
1203	BaseAlign = std::min(BaseAlign, MaxFieldAlignment);
1204	UnpackedBaseAlign = std::min(UnpackedBaseAlign, MaxFieldAlignment);
1205	}
1206
1207	if (!HasExternalLayout) {
1208	// Round up the current record size to the base's alignment boundary.
1209	Offset = getDataSize().alignTo(BaseAlign);
1210
1211	// Try to place the base.
1212	while (!EmptySubobjects->CanPlaceBaseAtOffset(Base, Offset))
1213	Offset += BaseAlign;
1214	} else {
1215	bool Allowed = EmptySubobjects->CanPlaceBaseAtOffset(Base, Offset);
1216	(void)Allowed;
1217	(0) . __assert_fail ("Allowed && \"Base subobject externally placed at overlapping offset\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1217, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Allowed && "Base subobject externally placed at overlapping offset");
1218
1219	if (InferAlignment && Offset < getDataSize().alignTo(BaseAlign)) {
1220	// The externally-supplied base offset is before the base offset we
1221	// computed. Assume that the structure is packed.
1222	Alignment = CharUnits::One();
1223	InferAlignment = false;
1224	}
1225	}
1226
1227	if (!Base->Class->isEmpty()) {
1228	// Update the data size.
1229	setDataSize(Offset + Layout.getNonVirtualSize());
1230
1231	setSize(std::max(getSize(), getDataSize()));
1232	} else
1233	setSize(std::max(getSize(), Offset + Layout.getSize()));
1234
1235	// Remember max struct/class alignment.
1236	UpdateAlignment(BaseAlign, UnpackedBaseAlign);
1237
1238	return Offset;
1239	}
1240
1241	void ItaniumRecordLayoutBuilder::InitializeLayout(const Decl *D) {
1242	if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) {
1243	IsUnion = RD->isUnion();
1244	IsMsStruct = RD->isMsStruct(Context);
1245	}
1246
1247	Packed = D->hasAttr<PackedAttr>();
1248
1249	// Honor the default struct packing maximum alignment flag.
1250	if (unsigned DefaultMaxFieldAlignment = Context.getLangOpts().PackStruct) {
1251	MaxFieldAlignment = CharUnits::fromQuantity(DefaultMaxFieldAlignment);
1252	}
1253
1254	// mac68k alignment supersedes maximum field alignment and attribute aligned,
1255	// and forces all structures to have 2-byte alignment. The IBM docs on it
1256	// allude to additional (more complicated) semantics, especially with regard
1257	// to bit-fields, but gcc appears not to follow that.
1258	if (D->hasAttr<AlignMac68kAttr>()) {
1259	IsMac68kAlign = true;
1260	MaxFieldAlignment = CharUnits::fromQuantity(2);
1261	Alignment = CharUnits::fromQuantity(2);
1262	} else {
1263	if (const MaxFieldAlignmentAttr *MFAA = D->getAttr<MaxFieldAlignmentAttr>())
1264	MaxFieldAlignment = Context.toCharUnitsFromBits(MFAA->getAlignment());
1265
1266	if (unsigned MaxAlign = D->getMaxAlignment())
1267	UpdateAlignment(Context.toCharUnitsFromBits(MaxAlign));
1268	}
1269
1270	// If there is an external AST source, ask it for the various offsets.
1271	if (const RecordDecl *RD = dyn_cast<RecordDecl>(D))
1272	if (ExternalASTSource *Source = Context.getExternalSource()) {
1273	UseExternalLayout = Source->layoutRecordType(
1274	RD, External.Size, External.Align, External.FieldOffsets,
1275	External.BaseOffsets, External.VirtualBaseOffsets);
1276
1277	// Update based on external alignment.
1278	if (UseExternalLayout) {
1279	if (External.Align > 0) {
1280	Alignment = Context.toCharUnitsFromBits(External.Align);
1281	} else {
1282	// The external source didn't have alignment information; infer it.
1283	InferAlignment = true;
1284	}
1285	}
1286	}
1287	}
1288
1289	void ItaniumRecordLayoutBuilder::Layout(const RecordDecl *D) {
1290	InitializeLayout(D);
1291	LayoutFields(D);
1292
1293	// Finally, round the size of the total struct up to the alignment of the
1294	// struct itself.
1295	FinishLayout(D);
1296	}
1297
1298	void ItaniumRecordLayoutBuilder::Layout(const CXXRecordDecl *RD) {
1299	InitializeLayout(RD);
1300
1301	// Lay out the vtable and the non-virtual bases.
1302	LayoutNonVirtualBases(RD);
1303
1304	LayoutFields(RD);
1305
1306	NonVirtualSize = Context.toCharUnitsFromBits(
1307	llvm::alignTo(getSizeInBits(), Context.getTargetInfo().getCharAlign()));
1308	NonVirtualAlignment = Alignment;
1309
1310	// Lay out the virtual bases and add the primary virtual base offsets.
1311	LayoutVirtualBases(RD, RD);
1312
1313	// Finally, round the size of the total struct up to the alignment
1314	// of the struct itself.
1315	FinishLayout(RD);
1316
1317	#ifndef NDEBUG
1318	// Check that we have base offsets for all bases.
1319	for (const CXXBaseSpecifier &Base : RD->bases()) {
1320	if (Base.isVirtual())
1321	continue;
1322
1323	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
1324
1325	(0) . __assert_fail ("Bases.count(BaseDecl) && \"Did not find base offset!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1325, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Bases.count(BaseDecl) && "Did not find base offset!");
1326	}
1327
1328	// And all virtual bases.
1329	for (const CXXBaseSpecifier &Base : RD->vbases()) {
1330	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
1331
1332	(0) . __assert_fail ("VBases.count(BaseDecl) && \"Did not find base offset!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1332, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(VBases.count(BaseDecl) && "Did not find base offset!");
1333	}
1334	#endif
1335	}
1336
1337	void ItaniumRecordLayoutBuilder::Layout(const ObjCInterfaceDecl *D) {
1338	if (ObjCInterfaceDecl *SD = D->getSuperClass()) {
1339	const ASTRecordLayout &SL = Context.getASTObjCInterfaceLayout(SD);
1340
1341	UpdateAlignment(SL.getAlignment());
1342
1343	// We start laying out ivars not at the end of the superclass
1344	// structure, but at the next byte following the last field.
1345	setSize(SL.getDataSize());
1346	setDataSize(getSize());
1347	}
1348
1349	InitializeLayout(D);
1350	// Layout each ivar sequentially.
1351	for (const ObjCIvarDecl *IVD = D->all_declared_ivar_begin(); IVD;
1352	IVD = IVD->getNextIvar())
1353	LayoutField(IVD, false);
1354
1355	// Finally, round the size of the total struct up to the alignment of the
1356	// struct itself.
1357	FinishLayout(D);
1358	}
1359
1360	void ItaniumRecordLayoutBuilder::LayoutFields(const RecordDecl *D) {
1361	// Layout each field, for now, just sequentially, respecting alignment. In
1362	// the future, this will need to be tweakable by targets.
1363	bool InsertExtraPadding = D->mayInsertExtraPadding(/EmitRemark=/true);
1364	bool HasFlexibleArrayMember = D->hasFlexibleArrayMember();
1365	for (auto I = D->field_begin(), End = D->field_end(); I != End; ++I) {
1366	auto Next(I);
1367	++Next;
1368	LayoutField(*I,
1369	InsertExtraPadding && (Next != End \|\| !HasFlexibleArrayMember));
1370	}
1371	}
1372
1373	// Rounds the specified size to have it a multiple of the char size.
1374	static uint64_t
1375	roundUpSizeToCharAlignment(uint64_t Size,
1376	const ASTContext &Context) {
1377	uint64_t CharAlignment = Context.getTargetInfo().getCharAlign();
1378	return llvm::alignTo(Size, CharAlignment);
1379	}
1380
1381	void ItaniumRecordLayoutBuilder::LayoutWideBitField(uint64_t FieldSize,
1382	uint64_t TypeSize,
1383	bool FieldPacked,
1384	const FieldDecl *D) {
1385	(0) . __assert_fail ("Context.getLangOpts().CPlusPlus && \"Can only have wide bit-fields in C++!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1386, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Context.getLangOpts().CPlusPlus &&
1386	(0) . __assert_fail ("Context.getLangOpts().CPlusPlus && \"Can only have wide bit-fields in C++!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1386, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Can only have wide bit-fields in C++!");
1387
1388	// Itanium C++ ABI 2.4:
1389	// If sizeof(T)*8 < n, let T' be the largest integral POD type with
1390	// sizeof(T')*8 <= n.
1391
1392	QualType IntegralPODTypes[] = {
1393	Context.UnsignedCharTy, Context.UnsignedShortTy, Context.UnsignedIntTy,
1394	Context.UnsignedLongTy, Context.UnsignedLongLongTy
1395	};
1396
1397	QualType Type;
1398	for (const QualType &QT : IntegralPODTypes) {
1399	uint64_t Size = Context.getTypeSize(QT);
1400
1401	if (Size > FieldSize)
1402	break;
1403
1404	Type = QT;
1405	}
1406	(0) . __assert_fail ("!Type.isNull() && \"Did not find a type!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1406, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Type.isNull() && "Did not find a type!");
1407
1408	CharUnits TypeAlign = Context.getTypeAlignInChars(Type);
1409
1410	// We're not going to use any of the unfilled bits in the last byte.
1411	UnfilledBitsInLastUnit = 0;
1412	LastBitfieldTypeSize = 0;
1413
1414	uint64_t FieldOffset;
1415	uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
1416
1417	if (IsUnion) {
1418	uint64_t RoundedFieldSize = roundUpSizeToCharAlignment(FieldSize,
1419	Context);
1420	setDataSize(std::max(getDataSizeInBits(), RoundedFieldSize));
1421	FieldOffset = 0;
1422	} else {
1423	// The bitfield is allocated starting at the next offset aligned
1424	// appropriately for T', with length n bits.
1425	FieldOffset = llvm::alignTo(getDataSizeInBits(), Context.toBits(TypeAlign));
1426
1427	uint64_t NewSizeInBits = FieldOffset + FieldSize;
1428
1429	setDataSize(
1430	llvm::alignTo(NewSizeInBits, Context.getTargetInfo().getCharAlign()));
1431	UnfilledBitsInLastUnit = getDataSizeInBits() - NewSizeInBits;
1432	}
1433
1434	// Place this field at the current location.
1435	FieldOffsets.push_back(FieldOffset);
1436
1437	CheckFieldPadding(FieldOffset, UnpaddedFieldOffset, FieldOffset,
1438	Context.toBits(TypeAlign), FieldPacked, D);
1439
1440	// Update the size.
1441	setSize(std::max(getSizeInBits(), getDataSizeInBits()));
1442
1443	// Remember max struct/class alignment.
1444	UpdateAlignment(TypeAlign);
1445	}
1446
1447	void ItaniumRecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
1448	bool FieldPacked = Packed \|\| D->hasAttr<PackedAttr>();
1449	uint64_t FieldSize = D->getBitWidthValue(Context);
1450	TypeInfo FieldInfo = Context.getTypeInfo(D->getType());
1451	uint64_t TypeSize = FieldInfo.Width;
1452	unsigned FieldAlign = FieldInfo.Align;
1453
1454	// UnfilledBitsInLastUnit is the difference between the end of the
1455	// last allocated bitfield (i.e. the first bit offset available for
1456	// bitfields) and the end of the current data size in bits (i.e. the
1457	// first bit offset available for non-bitfields). The current data
1458	// size in bits is always a multiple of the char size; additionally,
1459	// for ms_struct records it's also a multiple of the
1460	// LastBitfieldTypeSize (if set).
1461
1462	// The struct-layout algorithm is dictated by the platform ABI,
1463	// which in principle could use almost any rules it likes. In
1464	// practice, UNIXy targets tend to inherit the algorithm described
1465	// in the System V generic ABI. The basic bitfield layout rule in
1466	// System V is to place bitfields at the next available bit offset
1467	// where the entire bitfield would fit in an aligned storage unit of
1468	// the declared type; it's okay if an earlier or later non-bitfield
1469	// is allocated in the same storage unit. However, some targets
1470	// (those that !useBitFieldTypeAlignment(), e.g. ARM APCS) don't
1471	// require this storage unit to be aligned, and therefore always put
1472	// the bitfield at the next available bit offset.
1473
1474	// ms_struct basically requests a complete replacement of the
1475	// platform ABI's struct-layout algorithm, with the high-level goal
1476	// of duplicating MSVC's layout. For non-bitfields, this follows
1477	// the standard algorithm. The basic bitfield layout rule is to
1478	// allocate an entire unit of the bitfield's declared type
1479	// (e.g. 'unsigned long'), then parcel it up among successive
1480	// bitfields whose declared types have the same size, making a new
1481	// unit as soon as the last can no longer store the whole value.
1482	// Since it completely replaces the platform ABI's algorithm,
1483	// settings like !useBitFieldTypeAlignment() do not apply.
1484
1485	// A zero-width bitfield forces the use of a new storage unit for
1486	// later bitfields. In general, this occurs by rounding up the
1487	// current size of the struct as if the algorithm were about to
1488	// place a non-bitfield of the field's formal type. Usually this
1489	// does not change the alignment of the struct itself, but it does
1490	// on some targets (those that useZeroLengthBitfieldAlignment(),
1491	// e.g. ARM). In ms_struct layout, zero-width bitfields are
1492	// ignored unless they follow a non-zero-width bitfield.
1493
1494	// A field alignment restriction (e.g. from #pragma pack) or
1495	// specification (e.g. from __attribute__((aligned))) changes the
1496	// formal alignment of the field. For System V, this alters the
1497	// required alignment of the notional storage unit that must contain
1498	// the bitfield. For ms_struct, this only affects the placement of
1499	// new storage units. In both cases, the effect of #pragma pack is
1500	// ignored on zero-width bitfields.
1501
1502	// On System V, a packed field (e.g. from #pragma pack or
1503	// __attribute__((packed))) always uses the next available bit
1504	// offset.
1505
1506	// In an ms_struct struct, the alignment of a fundamental type is
1507	// always equal to its size. This is necessary in order to mimic
1508	// the i386 alignment rules on targets which might not fully align
1509	// all types (e.g. Darwin PPC32, where alignof(long long) == 4).
1510
1511	// First, some simple bookkeeping to perform for ms_struct structs.
1512	if (IsMsStruct) {
1513	// The field alignment for integer types is always the size.
1514	FieldAlign = TypeSize;
1515
1516	// If the previous field was not a bitfield, or was a bitfield
1517	// with a different storage unit size, or if this field doesn't fit into
1518	// the current storage unit, we're done with that storage unit.
1519	if (LastBitfieldTypeSize != TypeSize \|\|
1520	UnfilledBitsInLastUnit < FieldSize) {
1521	// Also, ignore zero-length bitfields after non-bitfields.
1522	if (!LastBitfieldTypeSize && !FieldSize)
1523	FieldAlign = 1;
1524
1525	UnfilledBitsInLastUnit = 0;
1526	LastBitfieldTypeSize = 0;
1527	}
1528	}
1529
1530	// If the field is wider than its declared type, it follows
1531	// different rules in all cases.
1532	if (FieldSize > TypeSize) {
1533	LayoutWideBitField(FieldSize, TypeSize, FieldPacked, D);
1534	return;
1535	}
1536
1537	// Compute the next available bit offset.
1538	uint64_t FieldOffset =
1539	IsUnion ? 0 : (getDataSizeInBits() - UnfilledBitsInLastUnit);
1540
1541	// Handle targets that don't honor bitfield type alignment.
1542	if (!IsMsStruct && !Context.getTargetInfo().useBitFieldTypeAlignment()) {
1543	// Some such targets do honor it on zero-width bitfields.
1544	if (FieldSize == 0 &&
1545	Context.getTargetInfo().useZeroLengthBitfieldAlignment()) {
1546	// The alignment to round up to is the max of the field's natural
1547	// alignment and a target-specific fixed value (sometimes zero).
1548	unsigned ZeroLengthBitfieldBoundary =
1549	Context.getTargetInfo().getZeroLengthBitfieldBoundary();
1550	FieldAlign = std::max(FieldAlign, ZeroLengthBitfieldBoundary);
1551
1552	// If that doesn't apply, just ignore the field alignment.
1553	} else {
1554	FieldAlign = 1;
1555	}
1556	}
1557
1558	// Remember the alignment we would have used if the field were not packed.
1559	unsigned UnpackedFieldAlign = FieldAlign;
1560
1561	// Ignore the field alignment if the field is packed unless it has zero-size.
1562	if (!IsMsStruct && FieldPacked && FieldSize != 0)
1563	FieldAlign = 1;
1564
1565	// But, if there's an 'aligned' attribute on the field, honor that.
1566	unsigned ExplicitFieldAlign = D->getMaxAlignment();
1567	if (ExplicitFieldAlign) {
1568	FieldAlign = std::max(FieldAlign, ExplicitFieldAlign);
1569	UnpackedFieldAlign = std::max(UnpackedFieldAlign, ExplicitFieldAlign);
1570	}
1571
1572	// But, if there's a #pragma pack in play, that takes precedent over
1573	// even the 'aligned' attribute, for non-zero-width bitfields.
1574	unsigned MaxFieldAlignmentInBits = Context.toBits(MaxFieldAlignment);
1575	if (!MaxFieldAlignment.isZero() && FieldSize) {
1576	UnpackedFieldAlign = std::min(UnpackedFieldAlign, MaxFieldAlignmentInBits);
1577	if (FieldPacked)
1578	FieldAlign = UnpackedFieldAlign;
1579	else
1580	FieldAlign = std::min(FieldAlign, MaxFieldAlignmentInBits);
1581	}
1582
1583	// But, ms_struct just ignores all of that in unions, even explicit
1584	// alignment attributes.
1585	if (IsMsStruct && IsUnion) {
1586	FieldAlign = UnpackedFieldAlign = 1;
1587	}
1588
1589	// For purposes of diagnostics, we're going to simultaneously
1590	// compute the field offsets that we would have used if we weren't
1591	// adding any alignment padding or if the field weren't packed.
1592	uint64_t UnpaddedFieldOffset = FieldOffset;
1593	uint64_t UnpackedFieldOffset = FieldOffset;
1594
1595	// Check if we need to add padding to fit the bitfield within an
1596	// allocation unit with the right size and alignment. The rules are
1597	// somewhat different here for ms_struct structs.
1598	if (IsMsStruct) {
1599	// If it's not a zero-width bitfield, and we can fit the bitfield
1600	// into the active storage unit (and we haven't already decided to
1601	// start a new storage unit), just do so, regardless of any other
1602	// other consideration. Otherwise, round up to the right alignment.
1603	if (FieldSize == 0 \|\| FieldSize > UnfilledBitsInLastUnit) {
1604	FieldOffset = llvm::alignTo(FieldOffset, FieldAlign);
1605	UnpackedFieldOffset =
1606	llvm::alignTo(UnpackedFieldOffset, UnpackedFieldAlign);
1607	UnfilledBitsInLastUnit = 0;
1608	}
1609
1610	} else {
1611	// #pragma pack, with any value, suppresses the insertion of padding.
1612	bool AllowPadding = MaxFieldAlignment.isZero();
1613
1614	// Compute the real offset.
1615	if (FieldSize == 0 \|\|
1616	(AllowPadding &&
1617	(FieldOffset & (FieldAlign-1)) + FieldSize > TypeSize)) {
1618	FieldOffset = llvm::alignTo(FieldOffset, FieldAlign);
1619	} else if (ExplicitFieldAlign &&
1620	(MaxFieldAlignmentInBits == 0 \|\|
1621	ExplicitFieldAlign <= MaxFieldAlignmentInBits) &&
1622	Context.getTargetInfo().useExplicitBitFieldAlignment()) {
1623	// TODO: figure it out what needs to be done on targets that don't honor
1624	// bit-field type alignment like ARM APCS ABI.
1625	FieldOffset = llvm::alignTo(FieldOffset, ExplicitFieldAlign);
1626	}
1627
1628	// Repeat the computation for diagnostic purposes.
1629	if (FieldSize == 0 \|\|
1630	(AllowPadding &&
1631	(UnpackedFieldOffset & (UnpackedFieldAlign-1)) + FieldSize > TypeSize))
1632	UnpackedFieldOffset =
1633	llvm::alignTo(UnpackedFieldOffset, UnpackedFieldAlign);
1634	else if (ExplicitFieldAlign &&
1635	(MaxFieldAlignmentInBits == 0 \|\|
1636	ExplicitFieldAlign <= MaxFieldAlignmentInBits) &&
1637	Context.getTargetInfo().useExplicitBitFieldAlignment())
1638	UnpackedFieldOffset =
1639	llvm::alignTo(UnpackedFieldOffset, ExplicitFieldAlign);
1640	}
1641
1642	// If we're using external layout, give the external layout a chance
1643	// to override this information.
1644	if (UseExternalLayout)
1645	FieldOffset = updateExternalFieldOffset(D, FieldOffset);
1646
1647	// Okay, place the bitfield at the calculated offset.
1648	FieldOffsets.push_back(FieldOffset);
1649
1650	// Bookkeeping:
1651
1652	// Anonymous members don't affect the overall record alignment,
1653	// except on targets where they do.
1654	if (!IsMsStruct &&
1655	!Context.getTargetInfo().useZeroLengthBitfieldAlignment() &&
1656	!D->getIdentifier())
1657	FieldAlign = UnpackedFieldAlign = 1;
1658
1659	// Diagnose differences in layout due to padding or packing.
1660	if (!UseExternalLayout)
1661	CheckFieldPadding(FieldOffset, UnpaddedFieldOffset, UnpackedFieldOffset,
1662	UnpackedFieldAlign, FieldPacked, D);
1663
1664	// Update DataSize to include the last byte containing (part of) the bitfield.
1665
1666	// For unions, this is just a max operation, as usual.
1667	if (IsUnion) {
1668	// For ms_struct, allocate the entire storage unit --- unless this
1669	// is a zero-width bitfield, in which case just use a size of 1.
1670	uint64_t RoundedFieldSize;
1671	if (IsMsStruct) {
1672	RoundedFieldSize =
1673	(FieldSize ? TypeSize : Context.getTargetInfo().getCharWidth());
1674
1675	// Otherwise, allocate just the number of bytes required to store
1676	// the bitfield.
1677	} else {
1678	RoundedFieldSize = roundUpSizeToCharAlignment(FieldSize, Context);
1679	}
1680	setDataSize(std::max(getDataSizeInBits(), RoundedFieldSize));
1681
1682	// For non-zero-width bitfields in ms_struct structs, allocate a new
1683	// storage unit if necessary.
1684	} else if (IsMsStruct && FieldSize) {
1685	// We should have cleared UnfilledBitsInLastUnit in every case
1686	// where we changed storage units.
1687	if (!UnfilledBitsInLastUnit) {
1688	setDataSize(FieldOffset + TypeSize);
1689	UnfilledBitsInLastUnit = TypeSize;
1690	}
1691	UnfilledBitsInLastUnit -= FieldSize;
1692	LastBitfieldTypeSize = TypeSize;
1693
1694	// Otherwise, bump the data size up to include the bitfield,
1695	// including padding up to char alignment, and then remember how
1696	// bits we didn't use.
1697	} else {
1698	uint64_t NewSizeInBits = FieldOffset + FieldSize;
1699	uint64_t CharAlignment = Context.getTargetInfo().getCharAlign();
1700	setDataSize(llvm::alignTo(NewSizeInBits, CharAlignment));
1701	UnfilledBitsInLastUnit = getDataSizeInBits() - NewSizeInBits;
1702
1703	// The only time we can get here for an ms_struct is if this is a
1704	// zero-width bitfield, which doesn't count as anything for the
1705	// purposes of unfilled bits.
1706	LastBitfieldTypeSize = 0;
1707	}
1708
1709	// Update the size.
1710	setSize(std::max(getSizeInBits(), getDataSizeInBits()));
1711
1712	// Remember max struct/class alignment.
1713	UnadjustedAlignment =
1714	std::max(UnadjustedAlignment, Context.toCharUnitsFromBits(FieldAlign));
1715	UpdateAlignment(Context.toCharUnitsFromBits(FieldAlign),
1716	Context.toCharUnitsFromBits(UnpackedFieldAlign));
1717	}
1718
1719	void ItaniumRecordLayoutBuilder::LayoutField(const FieldDecl *D,
1720	bool InsertExtraPadding) {
1721	if (D->isBitField()) {
1722	LayoutBitField(D);
1723	return;
1724	}
1725
1726	uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
1727
1728	// Reset the unfilled bits.
1729	UnfilledBitsInLastUnit = 0;
1730	LastBitfieldTypeSize = 0;
1731
1732	bool FieldPacked = Packed \|\| D->hasAttr<PackedAttr>();
1733	CharUnits FieldOffset =
1734	IsUnion ? CharUnits::Zero() : getDataSize();
1735	CharUnits FieldSize;
1736	CharUnits FieldAlign;
1737
1738	if (D->getType()->isIncompleteArrayType()) {
1739	// This is a flexible array member; we can't directly
1740	// query getTypeInfo about these, so we figure it out here.
1741	// Flexible array members don't have any size, but they
1742	// have to be aligned appropriately for their element type.
1743	FieldSize = CharUnits::Zero();
1744	const ArrayType* ATy = Context.getAsArrayType(D->getType());
1745	FieldAlign = Context.getTypeAlignInChars(ATy->getElementType());
1746	} else if (const ReferenceType *RT = D->getType()->getAs<ReferenceType>()) {
1747	unsigned AS = Context.getTargetAddressSpace(RT->getPointeeType());
1748	FieldSize =
1749	Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(AS));
1750	FieldAlign =
1751	Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerAlign(AS));
1752	} else {
1753	std::pair<CharUnits, CharUnits> FieldInfo =
1754	Context.getTypeInfoInChars(D->getType());
1755	FieldSize = FieldInfo.first;
1756	FieldAlign = FieldInfo.second;
1757
1758	if (IsMsStruct) {
1759	// If MS bitfield layout is required, figure out what type is being
1760	// laid out and align the field to the width of that type.
1761
1762	// Resolve all typedefs down to their base type and round up the field
1763	// alignment if necessary.
1764	QualType T = Context.getBaseElementType(D->getType());
1765	if (const BuiltinType *BTy = T->getAs<BuiltinType>()) {
1766	CharUnits TypeSize = Context.getTypeSizeInChars(BTy);
1767
1768	if (!llvm::isPowerOf2_64(TypeSize.getQuantity())) {
1769	(0) . __assert_fail ("!Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment() && \"Non PowerOf2 size in MSVC mode\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1771, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(
1770	(0) . __assert_fail ("!Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment() && \"Non PowerOf2 size in MSVC mode\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1771, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> !Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment() &&
1771	(0) . __assert_fail ("!Context.getTargetInfo().getTriple().isWindowsMSVCEnvironment() && \"Non PowerOf2 size in MSVC mode\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1771, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Non PowerOf2 size in MSVC mode");
1772	// Base types with sizes that aren't a power of two don't work
1773	// with the layout rules for MS structs. This isn't an issue in
1774	// MSVC itself since there are no such base data types there.
1775	// On e.g. x86_32 mingw and linux, long double is 12 bytes though.
1776	// Any structs involving that data type obviously can't be ABI
1777	// compatible with MSVC regardless of how it is laid out.
1778
1779	// Since ms_struct can be mass enabled (via a pragma or via the
1780	// -mms-bitfields command line parameter), this can trigger for
1781	// structs that don't actually need MSVC compatibility, so we
1782	// need to be able to sidestep the ms_struct layout for these types.
1783
1784	// Since the combination of -mms-bitfields together with structs
1785	// like max_align_t (which contains a long double) for mingw is
1786	// quite comon (and GCC handles it silently), just handle it
1787	// silently there. For other targets that have ms_struct enabled
1788	// (most probably via a pragma or attribute), trigger a diagnostic
1789	// that defaults to an error.
1790	if (!Context.getTargetInfo().getTriple().isWindowsGNUEnvironment())
1791	Diag(D->getLocation(), diag::warn_npot_ms_struct);
1792	}
1793	if (TypeSize > FieldAlign &&
1794	llvm::isPowerOf2_64(TypeSize.getQuantity()))
1795	FieldAlign = TypeSize;
1796	}
1797	}
1798	}
1799
1800	// The align if the field is not packed. This is to check if the attribute
1801	// was unnecessary (-Wpacked).
1802	CharUnits UnpackedFieldAlign = FieldAlign;
1803	CharUnits UnpackedFieldOffset = FieldOffset;
1804
1805	if (FieldPacked)
1806	FieldAlign = CharUnits::One();
1807	CharUnits MaxAlignmentInChars =
1808	Context.toCharUnitsFromBits(D->getMaxAlignment());
1809	FieldAlign = std::max(FieldAlign, MaxAlignmentInChars);
1810	UnpackedFieldAlign = std::max(UnpackedFieldAlign, MaxAlignmentInChars);
1811
1812	// The maximum field alignment overrides the aligned attribute.
1813	if (!MaxFieldAlignment.isZero()) {
1814	FieldAlign = std::min(FieldAlign, MaxFieldAlignment);
1815	UnpackedFieldAlign = std::min(UnpackedFieldAlign, MaxFieldAlignment);
1816	}
1817
1818	// Round up the current record size to the field's alignment boundary.
1819	FieldOffset = FieldOffset.alignTo(FieldAlign);
1820	UnpackedFieldOffset = UnpackedFieldOffset.alignTo(UnpackedFieldAlign);
1821
1822	if (UseExternalLayout) {
1823	FieldOffset = Context.toCharUnitsFromBits(
1824	updateExternalFieldOffset(D, Context.toBits(FieldOffset)));
1825
1826	if (!IsUnion && EmptySubobjects) {
1827	// Record the fact that we're placing a field at this offset.
1828	bool Allowed = EmptySubobjects->CanPlaceFieldAtOffset(D, FieldOffset);
1829	(void)Allowed;
1830	(0) . __assert_fail ("Allowed && \"Externally-placed field cannot be placed here\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1830, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Allowed && "Externally-placed field cannot be placed here");
1831	}
1832	} else {
1833	if (!IsUnion && EmptySubobjects) {
1834	// Check if we can place the field at this offset.
1835	while (!EmptySubobjects->CanPlaceFieldAtOffset(D, FieldOffset)) {
1836	// We couldn't place the field at the offset. Try again at a new offset.
1837	FieldOffset += FieldAlign;
1838	}
1839	}
1840	}
1841
1842	// Place this field at the current location.
1843	FieldOffsets.push_back(Context.toBits(FieldOffset));
1844
1845	if (!UseExternalLayout)
1846	CheckFieldPadding(Context.toBits(FieldOffset), UnpaddedFieldOffset,
1847	Context.toBits(UnpackedFieldOffset),
1848	Context.toBits(UnpackedFieldAlign), FieldPacked, D);
1849
1850	if (InsertExtraPadding) {
1851	CharUnits ASanAlignment = CharUnits::fromQuantity(8);
1852	CharUnits ExtraSizeForAsan = ASanAlignment;
1853	if (FieldSize % ASanAlignment)
1854	ExtraSizeForAsan +=
1855	ASanAlignment - CharUnits::fromQuantity(FieldSize % ASanAlignment);
1856	FieldSize += ExtraSizeForAsan;
1857	}
1858
1859	// Reserve space for this field.
1860	uint64_t FieldSizeInBits = Context.toBits(FieldSize);
1861	if (IsUnion)
1862	setDataSize(std::max(getDataSizeInBits(), FieldSizeInBits));
1863	else
1864	setDataSize(FieldOffset + FieldSize);
1865
1866	// Update the size.
1867	setSize(std::max(getSizeInBits(), getDataSizeInBits()));
1868
1869	// Remember max struct/class alignment.
1870	UnadjustedAlignment = std::max(UnadjustedAlignment, FieldAlign);
1871	UpdateAlignment(FieldAlign, UnpackedFieldAlign);
1872	}
1873
1874	void ItaniumRecordLayoutBuilder::FinishLayout(const NamedDecl *D) {
1875	// In C++, records cannot be of size 0.
1876	if (Context.getLangOpts().CPlusPlus && getSizeInBits() == 0) {
1877	if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
1878	// Compatibility with gcc requires a class (pod or non-pod)
1879	// which is not empty but of size 0; such as having fields of
1880	// array of zero-length, remains of Size 0
1881	if (RD->isEmpty())
1882	setSize(CharUnits::One());
1883	}
1884	else
1885	setSize(CharUnits::One());
1886	}
1887
1888	// Finally, round the size of the record up to the alignment of the
1889	// record itself.
1890	uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastUnit;
1891	uint64_t UnpackedSizeInBits =
1892	llvm::alignTo(getSizeInBits(), Context.toBits(UnpackedAlignment));
1893	uint64_t RoundedSize =
1894	llvm::alignTo(getSizeInBits(), Context.toBits(Alignment));
1895
1896	if (UseExternalLayout) {
1897	// If we're inferring alignment, and the external size is smaller than
1898	// our size after we've rounded up to alignment, conservatively set the
1899	// alignment to 1.
1900	if (InferAlignment && External.Size < RoundedSize) {
1901	Alignment = CharUnits::One();
1902	InferAlignment = false;
1903	}
1904	setSize(External.Size);
1905	return;
1906	}
1907
1908	// Set the size to the final size.
1909	setSize(RoundedSize);
1910
1911	unsigned CharBitNum = Context.getTargetInfo().getCharWidth();
1912	if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) {
1913	// Warn if padding was introduced to the struct/class/union.
1914	if (getSizeInBits() > UnpaddedSize) {
1915	unsigned PadSize = getSizeInBits() - UnpaddedSize;
1916	bool InBits = true;
1917	if (PadSize % CharBitNum == 0) {
1918	PadSize = PadSize / CharBitNum;
1919	InBits = false;
1920	}
1921	Diag(RD->getLocation(), diag::warn_padded_struct_size)
1922	<< Context.getTypeDeclType(RD)
1923	<< PadSize
1924	<< (InBits ? 1 : 0); // (byte\|bit)
1925	}
1926
1927	// Warn if we packed it unnecessarily, when the unpacked alignment is not
1928	// greater than the one after packing, the size in bits doesn't change and
1929	// the offset of each field is identical.
1930	if (Packed && UnpackedAlignment <= Alignment &&
1931	UnpackedSizeInBits == getSizeInBits() && !HasPackedField)
1932	Diag(D->getLocation(), diag::warn_unnecessary_packed)
1933	<< Context.getTypeDeclType(RD);
1934	}
1935	}
1936
1937	void ItaniumRecordLayoutBuilder::UpdateAlignment(
1938	CharUnits NewAlignment, CharUnits UnpackedNewAlignment) {
1939	// The alignment is not modified when using 'mac68k' alignment or when
1940	// we have an externally-supplied layout that also provides overall alignment.
1941	if (IsMac68kAlign \|\| (UseExternalLayout && !InferAlignment))
1942	return;
1943
1944	if (NewAlignment > Alignment) {
1945	(0) . __assert_fail ("llvm..isPowerOf2_64(NewAlignment.getQuantity()) && \"Alignment not a power of 2\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1946, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(llvm::isPowerOf2_64(NewAlignment.getQuantity()) &&
1946	(0) . __assert_fail ("llvm..isPowerOf2_64(NewAlignment.getQuantity()) && \"Alignment not a power of 2\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1946, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Alignment not a power of 2");
1947	Alignment = NewAlignment;
1948	}
1949
1950	if (UnpackedNewAlignment > UnpackedAlignment) {
1951	(0) . __assert_fail ("llvm..isPowerOf2_64(UnpackedNewAlignment.getQuantity()) && \"Alignment not a power of 2\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1952, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(llvm::isPowerOf2_64(UnpackedNewAlignment.getQuantity()) &&
1952	(0) . __assert_fail ("llvm..isPowerOf2_64(UnpackedNewAlignment.getQuantity()) && \"Alignment not a power of 2\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 1952, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Alignment not a power of 2");
1953	UnpackedAlignment = UnpackedNewAlignment;
1954	}
1955	}
1956
1957	uint64_t
1958	ItaniumRecordLayoutBuilder::updateExternalFieldOffset(const FieldDecl *Field,
1959	uint64_t ComputedOffset) {
1960	uint64_t ExternalFieldOffset = External.getExternalFieldOffset(Field);
1961
1962	if (InferAlignment && ExternalFieldOffset < ComputedOffset) {
1963	// The externally-supplied field offset is before the field offset we
1964	// computed. Assume that the structure is packed.
1965	Alignment = CharUnits::One();
1966	InferAlignment = false;
1967	}
1968
1969	// Use the externally-supplied field offset.
1970	return ExternalFieldOffset;
1971	}
1972
1973	/// Get diagnostic %select index for tag kind for
1974	/// field padding diagnostic message.
1975	/// WARNING: Indexes apply to particular diagnostics only!
1976	///
1977	/// \returns diagnostic %select index.
1978	static unsigned getPaddingDiagFromTagKind(TagTypeKind Tag) {
1979	switch (Tag) {
1980	case TTK_Struct: return 0;
1981	case TTK_Interface: return 1;
1982	case TTK_Class: return 2;
1983	default: llvm_unreachable("Invalid tag kind for field padding diagnostic!");
1984	}
1985	}
1986
1987	void ItaniumRecordLayoutBuilder::CheckFieldPadding(
1988	uint64_t Offset, uint64_t UnpaddedOffset, uint64_t UnpackedOffset,
1989	unsigned UnpackedAlign, bool isPacked, const FieldDecl *D) {
1990	// We let objc ivars without warning, objc interfaces generally are not used
1991	// for padding tricks.
1992	if (isa<ObjCIvarDecl>(D))
1993	return;
1994
1995	// Don't warn about structs created without a SourceLocation. This can
1996	// be done by clients of the AST, such as codegen.
1997	if (D->getLocation().isInvalid())
1998	return;
1999
2000	unsigned CharBitNum = Context.getTargetInfo().getCharWidth();
2001
2002	// Warn if padding was introduced to the struct/class.
2003	if (!IsUnion && Offset > UnpaddedOffset) {
2004	unsigned PadSize = Offset - UnpaddedOffset;
2005	bool InBits = true;
2006	if (PadSize % CharBitNum == 0) {
2007	PadSize = PadSize / CharBitNum;
2008	InBits = false;
2009	}
2010	if (D->getIdentifier())
2011	Diag(D->getLocation(), diag::warn_padded_struct_field)
2012	<< getPaddingDiagFromTagKind(D->getParent()->getTagKind())
2013	<< Context.getTypeDeclType(D->getParent())
2014	<< PadSize
2015	<< (InBits ? 1 : 0) // (byte\|bit)
2016	<< D->getIdentifier();
2017	else
2018	Diag(D->getLocation(), diag::warn_padded_struct_anon_field)
2019	<< getPaddingDiagFromTagKind(D->getParent()->getTagKind())
2020	<< Context.getTypeDeclType(D->getParent())
2021	<< PadSize
2022	<< (InBits ? 1 : 0); // (byte\|bit)
2023	}
2024	if (isPacked && Offset != UnpackedOffset) {
2025	HasPackedField = true;
2026	}
2027	}
2028
2029	static const CXXMethodDecl *computeKeyFunction(ASTContext &Context,
2030	const CXXRecordDecl *RD) {
2031	// If a class isn't polymorphic it doesn't have a key function.
2032	if (!RD->isPolymorphic())
2033	return nullptr;
2034
2035	// A class that is not externally visible doesn't have a key function. (Or
2036	// at least, there's no point to assigning a key function to such a class;
2037	// this doesn't affect the ABI.)
2038	if (!RD->isExternallyVisible())
2039	return nullptr;
2040
2041	// Template instantiations don't have key functions per Itanium C++ ABI 5.2.6.
2042	// Same behavior as GCC.
2043	TemplateSpecializationKind TSK = RD->getTemplateSpecializationKind();
2044	if (TSK == TSK_ImplicitInstantiation \|\|
2045	TSK == TSK_ExplicitInstantiationDeclaration \|\|
2046	TSK == TSK_ExplicitInstantiationDefinition)
2047	return nullptr;
2048
2049	bool allowInlineFunctions =
2050	Context.getTargetInfo().getCXXABI().canKeyFunctionBeInline();
2051
2052	for (const CXXMethodDecl *MD : RD->methods()) {
2053	if (!MD->isVirtual())
2054	continue;
2055
2056	if (MD->isPure())
2057	continue;
2058
2059	// Ignore implicit member functions, they are always marked as inline, but
2060	// they don't have a body until they're defined.
2061	if (MD->isImplicit())
2062	continue;
2063
2064	if (MD->isInlineSpecified())
2065	continue;
2066
2067	if (MD->hasInlineBody())
2068	continue;
2069
2070	// Ignore inline deleted or defaulted functions.
2071	if (!MD->isUserProvided())
2072	continue;
2073
2074	// In certain ABIs, ignore functions with out-of-line inline definitions.
2075	if (!allowInlineFunctions) {
2076	const FunctionDecl *Def;
2077	if (MD->hasBody(Def) && Def->isInlineSpecified())
2078	continue;
2079	}
2080
2081	if (Context.getLangOpts().CUDA) {
2082	// While compiler may see key method in this TU, during CUDA
2083	// compilation we should ignore methods that are not accessible
2084	// on this side of compilation.
2085	if (Context.getLangOpts().CUDAIsDevice) {
2086	// In device mode ignore methods without __device__ attribute.
2087	if (!MD->hasAttr<CUDADeviceAttr>())
2088	continue;
2089	} else {
2090	// In host mode ignore __device__-only methods.
2091	if (!MD->hasAttr<CUDAHostAttr>() && MD->hasAttr<CUDADeviceAttr>())
2092	continue;
2093	}
2094	}
2095
2096	// If the key function is dllimport but the class isn't, then the class has
2097	// no key function. The DLL that exports the key function won't export the
2098	// vtable in this case.
2099	if (MD->hasAttr<DLLImportAttr>() && !RD->hasAttr<DLLImportAttr>())
2100	return nullptr;
2101
2102	// We found it.
2103	return MD;
2104	}
2105
2106	return nullptr;
2107	}
2108
2109	DiagnosticBuilder ItaniumRecordLayoutBuilder::Diag(SourceLocation Loc,
2110	unsigned DiagID) {
2111	return Context.getDiagnostics().Report(Loc, DiagID);
2112	}
2113
2114	/// Does the target C++ ABI require us to skip over the tail-padding
2115	/// of the given class (considering it as a base class) when allocating
2116	/// objects?
2117	static bool mustSkipTailPadding(TargetCXXABI ABI, const CXXRecordDecl *RD) {
2118	switch (ABI.getTailPaddingUseRules()) {
2119	case TargetCXXABI::AlwaysUseTailPadding:
2120	return false;
2121
2122	case TargetCXXABI::UseTailPaddingUnlessPOD03:
2123	// FIXME: To the extent that this is meant to cover the Itanium ABI
2124	// rules, we should implement the restrictions about over-sized
2125	// bitfields:
2126	//
2127	// http://itanium-cxx-abi.github.io/cxx-abi/abi.html#POD :
2128	// In general, a type is considered a POD for the purposes of
2129	// layout if it is a POD type (in the sense of ISO C++
2130	// [basic.types]). However, a POD-struct or POD-union (in the
2131	// sense of ISO C++ [class]) with a bitfield member whose
2132	// declared width is wider than the declared type of the
2133	// bitfield is not a POD for the purpose of layout. Similarly,
2134	// an array type is not a POD for the purpose of layout if the
2135	// element type of the array is not a POD for the purpose of
2136	// layout.
2137	//
2138	// Where references to the ISO C++ are made in this paragraph,
2139	// the Technical Corrigendum 1 version of the standard is
2140	// intended.
2141	return RD->isPOD();
2142
2143	case TargetCXXABI::UseTailPaddingUnlessPOD11:
2144	// This is equivalent to RD->getTypeForDecl().isCXX11PODType(),
2145	// but with a lot of abstraction penalty stripped off. This does
2146	// assume that these properties are set correctly even in C++98
2147	// mode; fortunately, that is true because we want to assign
2148	// consistently semantics to the type-traits intrinsics (or at
2149	// least as many of them as possible).
2150	return RD->isTrivial() && RD->isCXX11StandardLayout();
2151	}
2152
2153	llvm_unreachable("bad tail-padding use kind");
2154	}
2155
2156	static bool isMsLayout(const ASTContext &Context) {
2157	return Context.getTargetInfo().getCXXABI().isMicrosoft();
2158	}
2159
2160	// This section contains an implementation of struct layout that is, up to the
2161	// included tests, compatible with cl.exe (2013). The layout produced is
2162	// significantly different than those produced by the Itanium ABI. Here we note
2163	// the most important differences.
2164	//
2165	// * The alignment of bitfields in unions is ignored when computing the
2166	// alignment of the union.
2167	// * The existence of zero-width bitfield that occurs after anything other than
2168	// a non-zero length bitfield is ignored.
2169	// * There is no explicit primary base for the purposes of layout. All bases
2170	// with vfptrs are laid out first, followed by all bases without vfptrs.
2171	// * The Itanium equivalent vtable pointers are split into a vfptr (virtual
2172	// function pointer) and a vbptr (virtual base pointer). They can each be
2173	// shared with a, non-virtual bases. These bases need not be the same. vfptrs
2174	// always occur at offset 0. vbptrs can occur at an arbitrary offset and are
2175	// placed after the lexicographically last non-virtual base. This placement
2176	// is always before fields but can be in the middle of the non-virtual bases
2177	// due to the two-pass layout scheme for non-virtual-bases.
2178	// * Virtual bases sometimes require a 'vtordisp' field that is laid out before
2179	// the virtual base and is used in conjunction with virtual overrides during
2180	// construction and destruction. This is always a 4 byte value and is used as
2181	// an alternative to constructor vtables.
2182	// * vtordisps are allocated in a block of memory with size and alignment equal
2183	// to the alignment of the completed structure (before applying __declspec(
2184	// align())). The vtordisp always occur at the end of the allocation block,
2185	// immediately prior to the virtual base.
2186	// * vfptrs are injected after all bases and fields have been laid out. In
2187	// order to guarantee proper alignment of all fields, the vfptr injection
2188	// pushes all bases and fields back by the alignment imposed by those bases
2189	// and fields. This can potentially add a significant amount of padding.
2190	// vfptrs are always injected at offset 0.
2191	// * vbptrs are injected after all bases and fields have been laid out. In
2192	// order to guarantee proper alignment of all fields, the vfptr injection
2193	// pushes all bases and fields back by the alignment imposed by those bases
2194	// and fields. This can potentially add a significant amount of padding.
2195	// vbptrs are injected immediately after the last non-virtual base as
2196	// lexicographically ordered in the code. If this site isn't pointer aligned
2197	// the vbptr is placed at the next properly aligned location. Enough padding
2198	// is added to guarantee a fit.
2199	// * The last zero sized non-virtual base can be placed at the end of the
2200	// struct (potentially aliasing another object), or may alias with the first
2201	// field, even if they are of the same type.
2202	// * The last zero size virtual base may be placed at the end of the struct
2203	// potentially aliasing another object.
2204	// * The ABI attempts to avoid aliasing of zero sized bases by adding padding
2205	// between bases or vbases with specific properties. The criteria for
2206	// additional padding between two bases is that the first base is zero sized
2207	// or ends with a zero sized subobject and the second base is zero sized or
2208	// trails with a zero sized base or field (sharing of vfptrs can reorder the
2209	// layout of the so the leading base is not always the first one declared).
2210	// This rule does take into account fields that are not records, so padding
2211	// will occur even if the last field is, e.g. an int. The padding added for
2212	// bases is 1 byte. The padding added between vbases depends on the alignment
2213	// of the object but is at least 4 bytes (in both 32 and 64 bit modes).
2214	// * There is no concept of non-virtual alignment, non-virtual alignment and
2215	// alignment are always identical.
2216	// * There is a distinction between alignment and required alignment.
2217	// __declspec(align) changes the required alignment of a struct. This
2218	// alignment is _always_ obeyed, even in the presence of #pragma pack. A
2219	// record inherits required alignment from all of its fields and bases.
2220	// * __declspec(align) on bitfields has the effect of changing the bitfield's
2221	// alignment instead of its required alignment. This is the only known way
2222	// to make the alignment of a struct bigger than 8. Interestingly enough
2223	// this alignment is also immune to the effects of #pragma pack and can be
2224	// used to create structures with large alignment under #pragma pack.
2225	// However, because it does not impact required alignment, such a structure,
2226	// when used as a field or base, will not be aligned if #pragma pack is
2227	// still active at the time of use.
2228	//
2229	// Known incompatibilities:
2230	// * all: #pragma pack between fields in a record
2231	// * 2010 and back: If the last field in a record is a bitfield, every object
2232	// laid out after the record will have extra padding inserted before it. The
2233	// extra padding will have size equal to the size of the storage class of the
2234	// bitfield. 0 sized bitfields don't exhibit this behavior and the extra
2235	// padding can be avoided by adding a 0 sized bitfield after the non-zero-
2236	// sized bitfield.
2237	// * 2012 and back: In 64-bit mode, if the alignment of a record is 16 or
2238	// greater due to __declspec(align()) then a second layout phase occurs after
2239	// The locations of the vf and vb pointers are known. This layout phase
2240	// suffers from the "last field is a bitfield" bug in 2010 and results in
2241	// _every_ field getting padding put in front of it, potentially including the
2242	// vfptr, leaving the vfprt at a non-zero location which results in a fault if
2243	// anything tries to read the vftbl. The second layout phase also treats
2244	// bitfields as separate entities and gives them each storage rather than
2245	// packing them. Additionally, because this phase appears to perform a
2246	// (an unstable) sort on the members before laying them out and because merged
2247	// bitfields have the same address, the bitfields end up in whatever order
2248	// the sort left them in, a behavior we could never hope to replicate.
2249
2250	namespace {
2251	struct MicrosoftRecordLayoutBuilder {
2252	struct ElementInfo {
2253	CharUnits Size;
2254	CharUnits Alignment;
2255	};
2256	typedef llvm::DenseMap<const CXXRecordDecl *, CharUnits> BaseOffsetsMapTy;
2257	MicrosoftRecordLayoutBuilder(const ASTContext &Context) : Context(Context) {}
2258	private:
2259	MicrosoftRecordLayoutBuilder(const MicrosoftRecordLayoutBuilder &) = delete;
2260	void operator=(const MicrosoftRecordLayoutBuilder &) = delete;
2261	public:
2262	void layout(const RecordDecl *RD);
2263	void cxxLayout(const CXXRecordDecl *RD);
2264	/// Initializes size and alignment and honors some flags.
2265	void initializeLayout(const RecordDecl *RD);
2266	/// Initialized C++ layout, compute alignment and virtual alignment and
2267	/// existence of vfptrs and vbptrs. Alignment is needed before the vfptr is
2268	/// laid out.
2269	void initializeCXXLayout(const CXXRecordDecl *RD);
2270	void layoutNonVirtualBases(const CXXRecordDecl *RD);
2271	void layoutNonVirtualBase(const CXXRecordDecl *RD,
2272	const CXXRecordDecl *BaseDecl,
2273	const ASTRecordLayout &BaseLayout,
2274	const ASTRecordLayout *&PreviousBaseLayout);
2275	void injectVFPtr(const CXXRecordDecl *RD);
2276	void injectVBPtr(const CXXRecordDecl *RD);
2277	/// Lays out the fields of the record. Also rounds size up to
2278	/// alignment.
2279	void layoutFields(const RecordDecl *RD);
2280	void layoutField(const FieldDecl *FD);
2281	void layoutBitField(const FieldDecl *FD);
2282	/// Lays out a single zero-width bit-field in the record and handles
2283	/// special cases associated with zero-width bit-fields.
2284	void layoutZeroWidthBitField(const FieldDecl *FD);
2285	void layoutVirtualBases(const CXXRecordDecl *RD);
2286	void finalizeLayout(const RecordDecl *RD);
2287	/// Gets the size and alignment of a base taking pragma pack and
2288	/// __declspec(align) into account.
2289	ElementInfo getAdjustedElementInfo(const ASTRecordLayout &Layout);
2290	/// Gets the size and alignment of a field taking pragma pack and
2291	/// __declspec(align) into account. It also updates RequiredAlignment as a
2292	/// side effect because it is most convenient to do so here.
2293	ElementInfo getAdjustedElementInfo(const FieldDecl *FD);
2294	/// Places a field at an offset in CharUnits.
2295	void placeFieldAtOffset(CharUnits FieldOffset) {
2296	FieldOffsets.push_back(Context.toBits(FieldOffset));
2297	}
2298	/// Places a bitfield at a bit offset.
2299	void placeFieldAtBitOffset(uint64_t FieldOffset) {
2300	FieldOffsets.push_back(FieldOffset);
2301	}
2302	/// Compute the set of virtual bases for which vtordisps are required.
2303	void computeVtorDispSet(
2304	llvm::SmallPtrSetImpl<const CXXRecordDecl *> &HasVtorDispSet,
2305	const CXXRecordDecl *RD) const;
2306	const ASTContext &Context;
2307	/// The size of the record being laid out.
2308	CharUnits Size;
2309	/// The non-virtual size of the record layout.
2310	CharUnits NonVirtualSize;
2311	/// The data size of the record layout.
2312	CharUnits DataSize;
2313	/// The current alignment of the record layout.
2314	CharUnits Alignment;
2315	/// The maximum allowed field alignment. This is set by #pragma pack.
2316	CharUnits MaxFieldAlignment;
2317	/// The alignment that this record must obey. This is imposed by
2318	/// __declspec(align()) on the record itself or one of its fields or bases.
2319	CharUnits RequiredAlignment;
2320	/// The size of the allocation of the currently active bitfield.
2321	/// This value isn't meaningful unless LastFieldIsNonZeroWidthBitfield
2322	/// is true.
2323	CharUnits CurrentBitfieldSize;
2324	/// Offset to the virtual base table pointer (if one exists).
2325	CharUnits VBPtrOffset;
2326	/// Minimum record size possible.
2327	CharUnits MinEmptyStructSize;
2328	/// The size and alignment info of a pointer.
2329	ElementInfo PointerInfo;
2330	/// The primary base class (if one exists).
2331	const CXXRecordDecl *PrimaryBase;
2332	/// The class we share our vb-pointer with.
2333	const CXXRecordDecl *SharedVBPtrBase;
2334	/// The collection of field offsets.
2335	SmallVector<uint64_t, 16> FieldOffsets;
2336	/// Base classes and their offsets in the record.
2337	BaseOffsetsMapTy Bases;
2338	/// virtual base classes and their offsets in the record.
2339	ASTRecordLayout::VBaseOffsetsMapTy VBases;
2340	/// The number of remaining bits in our last bitfield allocation.
2341	/// This value isn't meaningful unless LastFieldIsNonZeroWidthBitfield is
2342	/// true.
2343	unsigned RemainingBitsInField;
2344	bool IsUnion : 1;
2345	/// True if the last field laid out was a bitfield and was not 0
2346	/// width.
2347	bool LastFieldIsNonZeroWidthBitfield : 1;
2348	/// True if the class has its own vftable pointer.
2349	bool HasOwnVFPtr : 1;
2350	/// True if the class has a vbtable pointer.
2351	bool HasVBPtr : 1;
2352	/// True if the last sub-object within the type is zero sized or the
2353	/// object itself is zero sized. This does not count members that are not
2354	/// records. Only used for MS-ABI.
2355	bool EndsWithZeroSizedObject : 1;
2356	/// True if this class is zero sized or first base is zero sized or
2357	/// has this property. Only used for MS-ABI.
2358	bool LeadsWithZeroSizedBase : 1;
2359
2360	/// True if the external AST source provided a layout for this record.
2361	bool UseExternalLayout : 1;
2362
2363	/// The layout provided by the external AST source. Only active if
2364	/// UseExternalLayout is true.
2365	ExternalLayout External;
2366	};
2367	} // namespace
2368
2369	MicrosoftRecordLayoutBuilder::ElementInfo
2370	MicrosoftRecordLayoutBuilder::getAdjustedElementInfo(
2371	const ASTRecordLayout &Layout) {
2372	ElementInfo Info;
2373	Info.Alignment = Layout.getAlignment();
2374	// Respect pragma pack.
2375	if (!MaxFieldAlignment.isZero())
2376	Info.Alignment = std::min(Info.Alignment, MaxFieldAlignment);
2377	// Track zero-sized subobjects here where it's already available.
2378	EndsWithZeroSizedObject = Layout.endsWithZeroSizedObject();
2379	// Respect required alignment, this is necessary because we may have adjusted
2380	// the alignment in the case of pragam pack. Note that the required alignment
2381	// doesn't actually apply to the struct alignment at this point.
2382	Alignment = std::max(Alignment, Info.Alignment);
2383	RequiredAlignment = std::max(RequiredAlignment, Layout.getRequiredAlignment());
2384	Info.Alignment = std::max(Info.Alignment, Layout.getRequiredAlignment());
2385	Info.Size = Layout.getNonVirtualSize();
2386	return Info;
2387	}
2388
2389	MicrosoftRecordLayoutBuilder::ElementInfo
2390	MicrosoftRecordLayoutBuilder::getAdjustedElementInfo(
2391	const FieldDecl *FD) {
2392	// Get the alignment of the field type's natural alignment, ignore any
2393	// alignment attributes.
2394	ElementInfo Info;
2395	std::tie(Info.Size, Info.Alignment) =
2396	Context.getTypeInfoInChars(FD->getType()->getUnqualifiedDesugaredType());
2397	// Respect align attributes on the field.
2398	CharUnits FieldRequiredAlignment =
2399	Context.toCharUnitsFromBits(FD->getMaxAlignment());
2400	// Respect align attributes on the type.
2401	if (Context.isAlignmentRequired(FD->getType()))
2402	FieldRequiredAlignment = std::max(
2403	Context.getTypeAlignInChars(FD->getType()), FieldRequiredAlignment);
2404	// Respect attributes applied to subobjects of the field.
2405	if (FD->isBitField())
2406	// For some reason __declspec align impacts alignment rather than required
2407	// alignment when it is applied to bitfields.
2408	Info.Alignment = std::max(Info.Alignment, FieldRequiredAlignment);
2409	else {
2410	if (auto RT =
2411	FD->getType()->getBaseElementTypeUnsafe()->getAs<RecordType>()) {
2412	auto const &Layout = Context.getASTRecordLayout(RT->getDecl());
2413	EndsWithZeroSizedObject = Layout.endsWithZeroSizedObject();
2414	FieldRequiredAlignment = std::max(FieldRequiredAlignment,
2415	Layout.getRequiredAlignment());
2416	}
2417	// Capture required alignment as a side-effect.
2418	RequiredAlignment = std::max(RequiredAlignment, FieldRequiredAlignment);
2419	}
2420	// Respect pragma pack, attribute pack and declspec align
2421	if (!MaxFieldAlignment.isZero())
2422	Info.Alignment = std::min(Info.Alignment, MaxFieldAlignment);
2423	if (FD->hasAttr<PackedAttr>())
2424	Info.Alignment = CharUnits::One();
2425	Info.Alignment = std::max(Info.Alignment, FieldRequiredAlignment);
2426	return Info;
2427	}
2428
2429	void MicrosoftRecordLayoutBuilder::layout(const RecordDecl *RD) {
2430	// For C record layout, zero-sized records always have size 4.
2431	MinEmptyStructSize = CharUnits::fromQuantity(4);
2432	initializeLayout(RD);
2433	layoutFields(RD);
2434	DataSize = Size = Size.alignTo(Alignment);
2435	RequiredAlignment = std::max(
2436	RequiredAlignment, Context.toCharUnitsFromBits(RD->getMaxAlignment()));
2437	finalizeLayout(RD);
2438	}
2439
2440	void MicrosoftRecordLayoutBuilder::cxxLayout(const CXXRecordDecl *RD) {
2441	// The C++ standard says that empty structs have size 1.
2442	MinEmptyStructSize = CharUnits::One();
2443	initializeLayout(RD);
2444	initializeCXXLayout(RD);
2445	layoutNonVirtualBases(RD);
2446	layoutFields(RD);
2447	injectVBPtr(RD);
2448	injectVFPtr(RD);
2449	if (HasOwnVFPtr \|\| (HasVBPtr && !SharedVBPtrBase))
2450	Alignment = std::max(Alignment, PointerInfo.Alignment);
2451	auto RoundingAlignment = Alignment;
2452	if (!MaxFieldAlignment.isZero())
2453	RoundingAlignment = std::min(RoundingAlignment, MaxFieldAlignment);
2454	if (!UseExternalLayout)
2455	Size = Size.alignTo(RoundingAlignment);
2456	NonVirtualSize = Size;
2457	RequiredAlignment = std::max(
2458	RequiredAlignment, Context.toCharUnitsFromBits(RD->getMaxAlignment()));
2459	layoutVirtualBases(RD);
2460	finalizeLayout(RD);
2461	}
2462
2463	void MicrosoftRecordLayoutBuilder::initializeLayout(const RecordDecl *RD) {
2464	IsUnion = RD->isUnion();
2465	Size = CharUnits::Zero();
2466	Alignment = CharUnits::One();
2467	// In 64-bit mode we always perform an alignment step after laying out vbases.
2468	// In 32-bit mode we do not. The check to see if we need to perform alignment
2469	// checks the RequiredAlignment field and performs alignment if it isn't 0.
2470	RequiredAlignment = Context.getTargetInfo().getTriple().isArch64Bit()
2471	? CharUnits::One()
2472	: CharUnits::Zero();
2473	// Compute the maximum field alignment.
2474	MaxFieldAlignment = CharUnits::Zero();
2475	// Honor the default struct packing maximum alignment flag.
2476	if (unsigned DefaultMaxFieldAlignment = Context.getLangOpts().PackStruct)
2477	MaxFieldAlignment = CharUnits::fromQuantity(DefaultMaxFieldAlignment);
2478	// Honor the packing attribute. The MS-ABI ignores pragma pack if its larger
2479	// than the pointer size.
2480	if (const MaxFieldAlignmentAttr *MFAA = RD->getAttr<MaxFieldAlignmentAttr>()){
2481	unsigned PackedAlignment = MFAA->getAlignment();
2482	if (PackedAlignment <= Context.getTargetInfo().getPointerWidth(0))
2483	MaxFieldAlignment = Context.toCharUnitsFromBits(PackedAlignment);
2484	}
2485	// Packed attribute forces max field alignment to be 1.
2486	if (RD->hasAttr<PackedAttr>())
2487	MaxFieldAlignment = CharUnits::One();
2488
2489	// Try to respect the external layout if present.
2490	UseExternalLayout = false;
2491	if (ExternalASTSource *Source = Context.getExternalSource())
2492	UseExternalLayout = Source->layoutRecordType(
2493	RD, External.Size, External.Align, External.FieldOffsets,
2494	External.BaseOffsets, External.VirtualBaseOffsets);
2495	}
2496
2497	void
2498	MicrosoftRecordLayoutBuilder::initializeCXXLayout(const CXXRecordDecl *RD) {
2499	EndsWithZeroSizedObject = false;
2500	LeadsWithZeroSizedBase = false;
2501	HasOwnVFPtr = false;
2502	HasVBPtr = false;
2503	PrimaryBase = nullptr;
2504	SharedVBPtrBase = nullptr;
2505	// Calculate pointer size and alignment. These are used for vfptr and vbprt
2506	// injection.
2507	PointerInfo.Size =
2508	Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerWidth(0));
2509	PointerInfo.Alignment =
2510	Context.toCharUnitsFromBits(Context.getTargetInfo().getPointerAlign(0));
2511	// Respect pragma pack.
2512	if (!MaxFieldAlignment.isZero())
2513	PointerInfo.Alignment = std::min(PointerInfo.Alignment, MaxFieldAlignment);
2514	}
2515
2516	void
2517	MicrosoftRecordLayoutBuilder::layoutNonVirtualBases(const CXXRecordDecl *RD) {
2518	// The MS-ABI lays out all bases that contain leading vfptrs before it lays
2519	// out any bases that do not contain vfptrs. We implement this as two passes
2520	// over the bases. This approach guarantees that the primary base is laid out
2521	// first. We use these passes to calculate some additional aggregated
2522	// information about the bases, such as required alignment and the presence of
2523	// zero sized members.
2524	const ASTRecordLayout *PreviousBaseLayout = nullptr;
2525	// Iterate through the bases and lay out the non-virtual ones.
2526	for (const CXXBaseSpecifier &Base : RD->bases()) {
2527	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2528	const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
2529	// Mark and skip virtual bases.
2530	if (Base.isVirtual()) {
2531	HasVBPtr = true;
2532	continue;
2533	}
2534	// Check for a base to share a VBPtr with.
2535	if (!SharedVBPtrBase && BaseLayout.hasVBPtr()) {
2536	SharedVBPtrBase = BaseDecl;
2537	HasVBPtr = true;
2538	}
2539	// Only lay out bases with extendable VFPtrs on the first pass.
2540	if (!BaseLayout.hasExtendableVFPtr())
2541	continue;
2542	// If we don't have a primary base, this one qualifies.
2543	if (!PrimaryBase) {
2544	PrimaryBase = BaseDecl;
2545	LeadsWithZeroSizedBase = BaseLayout.leadsWithZeroSizedBase();
2546	}
2547	// Lay out the base.
2548	layoutNonVirtualBase(RD, BaseDecl, BaseLayout, PreviousBaseLayout);
2549	}
2550	// Figure out if we need a fresh VFPtr for this class.
2551	if (!PrimaryBase && RD->isDynamicClass())
2552	for (CXXRecordDecl::method_iterator i = RD->method_begin(),
2553	e = RD->method_end();
2554	!HasOwnVFPtr && i != e; ++i)
2555	HasOwnVFPtr = i->isVirtual() && i->size_overridden_methods() == 0;
2556	// If we don't have a primary base then we have a leading object that could
2557	// itself lead with a zero-sized object, something we track.
2558	bool CheckLeadingLayout = !PrimaryBase;
2559	// Iterate through the bases and lay out the non-virtual ones.
2560	for (const CXXBaseSpecifier &Base : RD->bases()) {
2561	if (Base.isVirtual())
2562	continue;
2563	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2564	const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
2565	// Only lay out bases without extendable VFPtrs on the second pass.
2566	if (BaseLayout.hasExtendableVFPtr()) {
2567	VBPtrOffset = Bases[BaseDecl] + BaseLayout.getNonVirtualSize();
2568	continue;
2569	}
2570	// If this is the first layout, check to see if it leads with a zero sized
2571	// object. If it does, so do we.
2572	if (CheckLeadingLayout) {
2573	CheckLeadingLayout = false;
2574	LeadsWithZeroSizedBase = BaseLayout.leadsWithZeroSizedBase();
2575	}
2576	// Lay out the base.
2577	layoutNonVirtualBase(RD, BaseDecl, BaseLayout, PreviousBaseLayout);
2578	VBPtrOffset = Bases[BaseDecl] + BaseLayout.getNonVirtualSize();
2579	}
2580	// Set our VBPtroffset if we know it at this point.
2581	if (!HasVBPtr)
2582	VBPtrOffset = CharUnits::fromQuantity(-1);
2583	else if (SharedVBPtrBase) {
2584	const ASTRecordLayout &Layout = Context.getASTRecordLayout(SharedVBPtrBase);
2585	VBPtrOffset = Bases[SharedVBPtrBase] + Layout.getVBPtrOffset();
2586	}
2587	}
2588
2589	static bool recordUsesEBO(const RecordDecl *RD) {
2590	if (!isa<CXXRecordDecl>(RD))
2591	return false;
2592	if (RD->hasAttr<EmptyBasesAttr>())
2593	return true;
2594	if (auto *LVA = RD->getAttr<LayoutVersionAttr>())
2595	// TODO: Double check with the next version of MSVC.
2596	if (LVA->getVersion() <= LangOptions::MSVC2015)
2597	return false;
2598	// TODO: Some later version of MSVC will change the default behavior of the
2599	// compiler to enable EBO by default. When this happens, we will need an
2600	// additional isCompatibleWithMSVC check.
2601	return false;
2602	}
2603
2604	void MicrosoftRecordLayoutBuilder::layoutNonVirtualBase(
2605	const CXXRecordDecl *RD,
2606	const CXXRecordDecl *BaseDecl,
2607	const ASTRecordLayout &BaseLayout,
2608	const ASTRecordLayout *&PreviousBaseLayout) {
2609	// Insert padding between two bases if the left first one is zero sized or
2610	// contains a zero sized subobject and the right is zero sized or one leads
2611	// with a zero sized base.
2612	bool MDCUsesEBO = recordUsesEBO(RD);
2613	if (PreviousBaseLayout && PreviousBaseLayout->endsWithZeroSizedObject() &&
2614	BaseLayout.leadsWithZeroSizedBase() && !MDCUsesEBO)
2615	Size++;
2616	ElementInfo Info = getAdjustedElementInfo(BaseLayout);
2617	CharUnits BaseOffset;
2618
2619	// Respect the external AST source base offset, if present.
2620	bool FoundBase = false;
2621	if (UseExternalLayout) {
2622	FoundBase = External.getExternalNVBaseOffset(BaseDecl, BaseOffset);
2623	if (FoundBase) {
2624	(0) . __assert_fail ("BaseOffset >= Size && \"base offset already allocated\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 2624, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseOffset >= Size && "base offset already allocated");
2625	Size = BaseOffset;
2626	}
2627	}
2628
2629	if (!FoundBase) {
2630	if (MDCUsesEBO && BaseDecl->isEmpty()) {
2631	assert(BaseLayout.getNonVirtualSize() == CharUnits::Zero());
2632	BaseOffset = CharUnits::Zero();
2633	} else {
2634	// Otherwise, lay the base out at the end of the MDC.
2635	BaseOffset = Size = Size.alignTo(Info.Alignment);
2636	}
2637	}
2638	Bases.insert(std::make_pair(BaseDecl, BaseOffset));
2639	Size += BaseLayout.getNonVirtualSize();
2640	PreviousBaseLayout = &BaseLayout;
2641	}
2642
2643	void MicrosoftRecordLayoutBuilder::layoutFields(const RecordDecl *RD) {
2644	LastFieldIsNonZeroWidthBitfield = false;
2645	for (const FieldDecl *Field : RD->fields())
2646	layoutField(Field);
2647	}
2648
2649	void MicrosoftRecordLayoutBuilder::layoutField(const FieldDecl *FD) {
2650	if (FD->isBitField()) {
2651	layoutBitField(FD);
2652	return;
2653	}
2654	LastFieldIsNonZeroWidthBitfield = false;
2655	ElementInfo Info = getAdjustedElementInfo(FD);
2656	Alignment = std::max(Alignment, Info.Alignment);
2657	CharUnits FieldOffset;
2658	if (UseExternalLayout)
2659	FieldOffset =
2660	Context.toCharUnitsFromBits(External.getExternalFieldOffset(FD));
2661	else if (IsUnion)
2662	FieldOffset = CharUnits::Zero();
2663	else
2664	FieldOffset = Size.alignTo(Info.Alignment);
2665	placeFieldAtOffset(FieldOffset);
2666	Size = std::max(Size, FieldOffset + Info.Size);
2667	}
2668
2669	void MicrosoftRecordLayoutBuilder::layoutBitField(const FieldDecl *FD) {
2670	unsigned Width = FD->getBitWidthValue(Context);
2671	if (Width == 0) {
2672	layoutZeroWidthBitField(FD);
2673	return;
2674	}
2675	ElementInfo Info = getAdjustedElementInfo(FD);
2676	// Clamp the bitfield to a containable size for the sake of being able
2677	// to lay them out. Sema will throw an error.
2678	if (Width > Context.toBits(Info.Size))
2679	Width = Context.toBits(Info.Size);
2680	// Check to see if this bitfield fits into an existing allocation. Note:
2681	// MSVC refuses to pack bitfields of formal types with different sizes
2682	// into the same allocation.
2683	if (!UseExternalLayout && !IsUnion && LastFieldIsNonZeroWidthBitfield &&
2684	CurrentBitfieldSize == Info.Size && Width <= RemainingBitsInField) {
2685	placeFieldAtBitOffset(Context.toBits(Size) - RemainingBitsInField);
2686	RemainingBitsInField -= Width;
2687	return;
2688	}
2689	LastFieldIsNonZeroWidthBitfield = true;
2690	CurrentBitfieldSize = Info.Size;
2691	if (UseExternalLayout) {
2692	auto FieldBitOffset = External.getExternalFieldOffset(FD);
2693	placeFieldAtBitOffset(FieldBitOffset);
2694	auto NewSize = Context.toCharUnitsFromBits(
2695	llvm::alignDown(FieldBitOffset, Context.toBits(Info.Alignment)) +
2696	Context.toBits(Info.Size));
2697	Size = std::max(Size, NewSize);
2698	Alignment = std::max(Alignment, Info.Alignment);
2699	} else if (IsUnion) {
2700	placeFieldAtOffset(CharUnits::Zero());
2701	Size = std::max(Size, Info.Size);
2702	// TODO: Add a Sema warning that MS ignores bitfield alignment in unions.
2703	} else {
2704	// Allocate a new block of memory and place the bitfield in it.
2705	CharUnits FieldOffset = Size.alignTo(Info.Alignment);
2706	placeFieldAtOffset(FieldOffset);
2707	Size = FieldOffset + Info.Size;
2708	Alignment = std::max(Alignment, Info.Alignment);
2709	RemainingBitsInField = Context.toBits(Info.Size) - Width;
2710	}
2711	}
2712
2713	void
2714	MicrosoftRecordLayoutBuilder::layoutZeroWidthBitField(const FieldDecl *FD) {
2715	// Zero-width bitfields are ignored unless they follow a non-zero-width
2716	// bitfield.
2717	if (!LastFieldIsNonZeroWidthBitfield) {
2718	placeFieldAtOffset(IsUnion ? CharUnits::Zero() : Size);
2719	// TODO: Add a Sema warning that MS ignores alignment for zero
2720	// sized bitfields that occur after zero-size bitfields or non-bitfields.
2721	return;
2722	}
2723	LastFieldIsNonZeroWidthBitfield = false;
2724	ElementInfo Info = getAdjustedElementInfo(FD);
2725	if (IsUnion) {
2726	placeFieldAtOffset(CharUnits::Zero());
2727	Size = std::max(Size, Info.Size);
2728	// TODO: Add a Sema warning that MS ignores bitfield alignment in unions.
2729	} else {
2730	// Round up the current record size to the field's alignment boundary.
2731	CharUnits FieldOffset = Size.alignTo(Info.Alignment);
2732	placeFieldAtOffset(FieldOffset);
2733	Size = FieldOffset;
2734	Alignment = std::max(Alignment, Info.Alignment);
2735	}
2736	}
2737
2738	void MicrosoftRecordLayoutBuilder::injectVBPtr(const CXXRecordDecl *RD) {
2739	if (!HasVBPtr \|\| SharedVBPtrBase)
2740	return;
2741	// Inject the VBPointer at the injection site.
2742	CharUnits InjectionSite = VBPtrOffset;
2743	// But before we do, make sure it's properly aligned.
2744	VBPtrOffset = VBPtrOffset.alignTo(PointerInfo.Alignment);
2745	// Determine where the first field should be laid out after the vbptr.
2746	CharUnits FieldStart = VBPtrOffset + PointerInfo.Size;
2747	// Shift everything after the vbptr down, unless we're using an external
2748	// layout.
2749	if (UseExternalLayout) {
2750	// It is possible that there were no fields or bases located after vbptr,
2751	// so the size was not adjusted before.
2752	if (Size < FieldStart)
2753	Size = FieldStart;
2754	return;
2755	}
2756	// Make sure that the amount we push the fields back by is a multiple of the
2757	// alignment.
2758	CharUnits Offset = (FieldStart - InjectionSite)
2759	.alignTo(std::max(RequiredAlignment, Alignment));
2760	Size += Offset;
2761	for (uint64_t &FieldOffset : FieldOffsets)
2762	FieldOffset += Context.toBits(Offset);
2763	for (BaseOffsetsMapTy::value_type &Base : Bases)
2764	if (Base.second >= InjectionSite)
2765	Base.second += Offset;
2766	}
2767
2768	void MicrosoftRecordLayoutBuilder::injectVFPtr(const CXXRecordDecl *RD) {
2769	if (!HasOwnVFPtr)
2770	return;
2771	// Make sure that the amount we push the struct back by is a multiple of the
2772	// alignment.
2773	CharUnits Offset =
2774	PointerInfo.Size.alignTo(std::max(RequiredAlignment, Alignment));
2775	// Push back the vbptr, but increase the size of the object and push back
2776	// regular fields by the offset only if not using external record layout.
2777	if (HasVBPtr)
2778	VBPtrOffset += Offset;
2779
2780	if (UseExternalLayout) {
2781	// The class may have no bases or fields, but still have a vfptr
2782	// (e.g. it's an interface class). The size was not correctly set before
2783	// in this case.
2784	if (FieldOffsets.empty() && Bases.empty())
2785	Size += Offset;
2786	return;
2787	}
2788
2789	Size += Offset;
2790
2791	// If we're using an external layout, the fields offsets have already
2792	// accounted for this adjustment.
2793	for (uint64_t &FieldOffset : FieldOffsets)
2794	FieldOffset += Context.toBits(Offset);
2795	for (BaseOffsetsMapTy::value_type &Base : Bases)
2796	Base.second += Offset;
2797	}
2798
2799	void MicrosoftRecordLayoutBuilder::layoutVirtualBases(const CXXRecordDecl *RD) {
2800	if (!HasVBPtr)
2801	return;
2802	// Vtordisps are always 4 bytes (even in 64-bit mode)
2803	CharUnits VtorDispSize = CharUnits::fromQuantity(4);
2804	CharUnits VtorDispAlignment = VtorDispSize;
2805	// vtordisps respect pragma pack.
2806	if (!MaxFieldAlignment.isZero())
2807	VtorDispAlignment = std::min(VtorDispAlignment, MaxFieldAlignment);
2808	// The alignment of the vtordisp is at least the required alignment of the
2809	// entire record. This requirement may be present to support vtordisp
2810	// injection.
2811	for (const CXXBaseSpecifier &VBase : RD->vbases()) {
2812	const CXXRecordDecl *BaseDecl = VBase.getType()->getAsCXXRecordDecl();
2813	const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
2814	RequiredAlignment =
2815	std::max(RequiredAlignment, BaseLayout.getRequiredAlignment());
2816	}
2817	VtorDispAlignment = std::max(VtorDispAlignment, RequiredAlignment);
2818	// Compute the vtordisp set.
2819	llvm::SmallPtrSet<const CXXRecordDecl *, 2> HasVtorDispSet;
2820	computeVtorDispSet(HasVtorDispSet, RD);
2821	// Iterate through the virtual bases and lay them out.
2822	const ASTRecordLayout *PreviousBaseLayout = nullptr;
2823	for (const CXXBaseSpecifier &VBase : RD->vbases()) {
2824	const CXXRecordDecl *BaseDecl = VBase.getType()->getAsCXXRecordDecl();
2825	const ASTRecordLayout &BaseLayout = Context.getASTRecordLayout(BaseDecl);
2826	bool HasVtordisp = HasVtorDispSet.count(BaseDecl) > 0;
2827	// Insert padding between two bases if the left first one is zero sized or
2828	// contains a zero sized subobject and the right is zero sized or one leads
2829	// with a zero sized base. The padding between virtual bases is 4
2830	// bytes (in both 32 and 64 bits modes) and always involves rounding up to
2831	// the required alignment, we don't know why.
2832	if ((PreviousBaseLayout && PreviousBaseLayout->endsWithZeroSizedObject() &&
2833	BaseLayout.leadsWithZeroSizedBase() && !recordUsesEBO(RD)) \|\|
2834	HasVtordisp) {
2835	Size = Size.alignTo(VtorDispAlignment) + VtorDispSize;
2836	Alignment = std::max(VtorDispAlignment, Alignment);
2837	}
2838	// Insert the virtual base.
2839	ElementInfo Info = getAdjustedElementInfo(BaseLayout);
2840	CharUnits BaseOffset;
2841
2842	// Respect the external AST source base offset, if present.
2843	if (UseExternalLayout) {
2844	if (!External.getExternalVBaseOffset(BaseDecl, BaseOffset))
2845	BaseOffset = Size;
2846	} else
2847	BaseOffset = Size.alignTo(Info.Alignment);
2848
2849	(0) . __assert_fail ("BaseOffset >= Size && \"base offset already allocated\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 2849, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(BaseOffset >= Size && "base offset already allocated");
2850
2851	VBases.insert(std::make_pair(BaseDecl,
2852	ASTRecordLayout::VBaseInfo(BaseOffset, HasVtordisp)));
2853	Size = BaseOffset + BaseLayout.getNonVirtualSize();
2854	PreviousBaseLayout = &BaseLayout;
2855	}
2856	}
2857
2858	void MicrosoftRecordLayoutBuilder::finalizeLayout(const RecordDecl *RD) {
2859	// Respect required alignment. Note that in 32-bit mode Required alignment
2860	// may be 0 and cause size not to be updated.
2861	DataSize = Size;
2862	if (!RequiredAlignment.isZero()) {
2863	Alignment = std::max(Alignment, RequiredAlignment);
2864	auto RoundingAlignment = Alignment;
2865	if (!MaxFieldAlignment.isZero())
2866	RoundingAlignment = std::min(RoundingAlignment, MaxFieldAlignment);
2867	RoundingAlignment = std::max(RoundingAlignment, RequiredAlignment);
2868	Size = Size.alignTo(RoundingAlignment);
2869	}
2870	if (Size.isZero()) {
2871	if (!recordUsesEBO(RD) \|\| !cast<CXXRecordDecl>(RD)->isEmpty()) {
2872	EndsWithZeroSizedObject = true;
2873	LeadsWithZeroSizedBase = true;
2874	}
2875	// Zero-sized structures have size equal to their alignment if a
2876	// __declspec(align) came into play.
2877	if (RequiredAlignment >= MinEmptyStructSize)
2878	Size = Alignment;
2879	else
2880	Size = MinEmptyStructSize;
2881	}
2882
2883	if (UseExternalLayout) {
2884	Size = Context.toCharUnitsFromBits(External.Size);
2885	if (External.Align)
2886	Alignment = Context.toCharUnitsFromBits(External.Align);
2887	}
2888	}
2889
2890	// Recursively walks the non-virtual bases of a class and determines if any of
2891	// them are in the bases with overridden methods set.
2892	static bool
2893	RequiresVtordisp(const llvm::SmallPtrSetImpl<const CXXRecordDecl *> &
2894	BasesWithOverriddenMethods,
2895	const CXXRecordDecl *RD) {
2896	if (BasesWithOverriddenMethods.count(RD))
2897	return true;
2898	// If any of a virtual bases non-virtual bases (recursively) requires a
2899	// vtordisp than so does this virtual base.
2900	for (const CXXBaseSpecifier &Base : RD->bases())
2901	if (!Base.isVirtual() &&
2902	RequiresVtordisp(BasesWithOverriddenMethods,
2903	Base.getType()->getAsCXXRecordDecl()))
2904	return true;
2905	return false;
2906	}
2907
2908	void MicrosoftRecordLayoutBuilder::computeVtorDispSet(
2909	llvm::SmallPtrSetImpl<const CXXRecordDecl *> &HasVtordispSet,
2910	const CXXRecordDecl *RD) const {
2911	// /vd2 or #pragma vtordisp(2): Always use vtordisps for virtual bases with
2912	// vftables.
2913	if (RD->getMSVtorDispMode() == MSVtorDispAttr::ForVFTable) {
2914	for (const CXXBaseSpecifier &Base : RD->vbases()) {
2915	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2916	const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
2917	if (Layout.hasExtendableVFPtr())
2918	HasVtordispSet.insert(BaseDecl);
2919	}
2920	return;
2921	}
2922
2923	// If any of our bases need a vtordisp for this type, so do we. Check our
2924	// direct bases for vtordisp requirements.
2925	for (const CXXBaseSpecifier &Base : RD->bases()) {
2926	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2927	const ASTRecordLayout &Layout = Context.getASTRecordLayout(BaseDecl);
2928	for (const auto &bi : Layout.getVBaseOffsetsMap())
2929	if (bi.second.hasVtorDisp())
2930	HasVtordispSet.insert(bi.first);
2931	}
2932	// We don't introduce any additional vtordisps if either:
2933	// * A user declared constructor or destructor aren't declared.
2934	// * #pragma vtordisp(0) or the /vd0 flag are in use.
2935	if ((!RD->hasUserDeclaredConstructor() && !RD->hasUserDeclaredDestructor()) \|\|
2936	RD->getMSVtorDispMode() == MSVtorDispAttr::Never)
2937	return;
2938	// /vd1 or #pragma vtordisp(1): Try to guess based on whether we think it's
2939	// possible for a partially constructed object with virtual base overrides to
2940	// escape a non-trivial constructor.
2941	getMSVtorDispMode() == MSVtorDispAttr..ForVBaseOverride", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 2941, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(RD->getMSVtorDispMode() == MSVtorDispAttr::ForVBaseOverride);
2942	// Compute a set of base classes which define methods we override. A virtual
2943	// base in this set will require a vtordisp. A virtual base that transitively
2944	// contains one of these bases as a non-virtual base will also require a
2945	// vtordisp.
2946	llvm::SmallPtrSet<const CXXMethodDecl *, 8> Work;
2947	llvm::SmallPtrSet<const CXXRecordDecl *, 2> BasesWithOverriddenMethods;
2948	// Seed the working set with our non-destructor, non-pure virtual methods.
2949	for (const CXXMethodDecl *MD : RD->methods())
2950	if (MD->isVirtual() && !isa<CXXDestructorDecl>(MD) && !MD->isPure())
2951	Work.insert(MD);
2952	while (!Work.empty()) {
2953	const CXXMethodDecl MD = Work.begin();
2954	auto MethodRange = MD->overridden_methods();
2955	// If a virtual method has no-overrides it lives in its parent's vtable.
2956	if (MethodRange.begin() == MethodRange.end())
2957	BasesWithOverriddenMethods.insert(MD->getParent());
2958	else
2959	Work.insert(MethodRange.begin(), MethodRange.end());
2960	// We've finished processing this element, remove it from the working set.
2961	Work.erase(MD);
2962	}
2963	// For each of our virtual bases, check if it is in the set of overridden
2964	// bases or if it transitively contains a non-virtual base that is.
2965	for (const CXXBaseSpecifier &Base : RD->vbases()) {
2966	const CXXRecordDecl *BaseDecl = Base.getType()->getAsCXXRecordDecl();
2967	if (!HasVtordispSet.count(BaseDecl) &&
2968	RequiresVtordisp(BasesWithOverriddenMethods, BaseDecl))
2969	HasVtordispSet.insert(BaseDecl);
2970	}
2971	}
2972
2973	/// getASTRecordLayout - Get or compute information about the layout of the
2974	/// specified record (struct/union/class), which indicates its size and field
2975	/// position information.
2976	const ASTRecordLayout &
2977	ASTContext::getASTRecordLayout(const RecordDecl *D) const {
2978	// These asserts test different things. A record has a definition
2979	// as soon as we begin to parse the definition. That definition is
2980	// not a complete definition (which is what isDefinition() tests)
2981	// until we finish parsing the definition.
2982
2983	if (D->hasExternalLexicalStorage() && !D->getDefinition())
2984	getExternalSource()->CompleteType(const_cast<RecordDecl*>(D));
2985
2986	D = D->getDefinition();
2987	(0) . __assert_fail ("D && \"Cannot get layout of forward declarations!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 2987, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(D && "Cannot get layout of forward declarations!");
2988	(0) . __assert_fail ("!D->isInvalidDecl() && \"Cannot get layout of invalid decl!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 2988, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!D->isInvalidDecl() && "Cannot get layout of invalid decl!");
2989	(0) . __assert_fail ("D->isCompleteDefinition() && \"Cannot layout type before complete!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 2989, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(D->isCompleteDefinition() && "Cannot layout type before complete!");
2990
2991	// Look up this layout, if already laid out, return what we have.
2992	// Note that we can't save a reference to the entry because this function
2993	// is recursive.
2994	const ASTRecordLayout *Entry = ASTRecordLayouts[D];
2995	if (Entry) return *Entry;
2996
2997	const ASTRecordLayout *NewEntry = nullptr;
2998
2999	if (isMsLayout(*this)) {
3000	MicrosoftRecordLayoutBuilder Builder(*this);
3001	if (const auto *RD = dyn_cast<CXXRecordDecl>(D)) {
3002	Builder.cxxLayout(RD);
3003	NewEntry = new (*this) ASTRecordLayout(
3004	*this, Builder.Size, Builder.Alignment, Builder.Alignment,
3005	Builder.RequiredAlignment,
3006	Builder.HasOwnVFPtr, Builder.HasOwnVFPtr \|\| Builder.PrimaryBase,
3007	Builder.VBPtrOffset, Builder.DataSize, Builder.FieldOffsets,
3008	Builder.NonVirtualSize, Builder.Alignment, CharUnits::Zero(),
3009	Builder.PrimaryBase, false, Builder.SharedVBPtrBase,
3010	Builder.EndsWithZeroSizedObject, Builder.LeadsWithZeroSizedBase,
3011	Builder.Bases, Builder.VBases);
3012	} else {
3013	Builder.layout(D);
3014	NewEntry = new (*this) ASTRecordLayout(
3015	*this, Builder.Size, Builder.Alignment, Builder.Alignment,
3016	Builder.RequiredAlignment,
3017	Builder.Size, Builder.FieldOffsets);
3018	}
3019	} else {
3020	if (const auto *RD = dyn_cast<CXXRecordDecl>(D)) {
3021	EmptySubobjectMap EmptySubobjects(*this, RD);
3022	ItaniumRecordLayoutBuilder Builder(*this, &EmptySubobjects);
3023	Builder.Layout(RD);
3024
3025	// In certain situations, we are allowed to lay out objects in the
3026	// tail-padding of base classes. This is ABI-dependent.
3027	// FIXME: this should be stored in the record layout.
3028	bool skipTailPadding =
3029	mustSkipTailPadding(getTargetInfo().getCXXABI(), RD);
3030
3031	// FIXME: This should be done in FinalizeLayout.
3032	CharUnits DataSize =
3033	skipTailPadding ? Builder.getSize() : Builder.getDataSize();
3034	CharUnits NonVirtualSize =
3035	skipTailPadding ? DataSize : Builder.NonVirtualSize;
3036	NewEntry = new (*this) ASTRecordLayout(
3037	*this, Builder.getSize(), Builder.Alignment, Builder.UnadjustedAlignment,
3038	/RequiredAlignment : used by MS-ABI)/
3039	Builder.Alignment, Builder.HasOwnVFPtr, RD->isDynamicClass(),
3040	CharUnits::fromQuantity(-1), DataSize, Builder.FieldOffsets,
3041	NonVirtualSize, Builder.NonVirtualAlignment,
3042	EmptySubobjects.SizeOfLargestEmptySubobject, Builder.PrimaryBase,
3043	Builder.PrimaryBaseIsVirtual, nullptr, false, false, Builder.Bases,
3044	Builder.VBases);
3045	} else {
3046	ItaniumRecordLayoutBuilder Builder(this, /EmptySubobjects=*/nullptr);
3047	Builder.Layout(D);
3048
3049	NewEntry = new (*this) ASTRecordLayout(
3050	*this, Builder.getSize(), Builder.Alignment, Builder.UnadjustedAlignment,
3051	/RequiredAlignment : used by MS-ABI)/
3052	Builder.Alignment, Builder.getSize(), Builder.FieldOffsets);
3053	}
3054	}
3055
3056	ASTRecordLayouts[D] = NewEntry;
3057
3058	if (getLangOpts().DumpRecordLayouts) {
3059	llvm::outs() << "\n*** Dumping AST Record Layout\n";
3060	DumpRecordLayout(D, llvm::outs(), getLangOpts().DumpRecordLayoutsSimple);
3061	}
3062
3063	return *NewEntry;
3064	}
3065
3066	const CXXMethodDecl ASTContext::getCurrentKeyFunction(const CXXRecordDecl RD) {
3067	if (!getTargetInfo().getCXXABI().hasKeyFunctions())
3068	return nullptr;
3069
3070	(0) . __assert_fail ("RD->getDefinition() && \"Cannot get key function for forward decl!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3070, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(RD->getDefinition() && "Cannot get key function for forward decl!");
3071	RD = RD->getDefinition();
3072
3073	// Beware:
3074	// 1) computing the key function might trigger deserialization, which might
3075	// invalidate iterators into KeyFunctions
3076	// 2) 'get' on the LazyDeclPtr might also trigger deserialization and
3077	// invalidate the LazyDeclPtr within the map itself
3078	LazyDeclPtr Entry = KeyFunctions[RD];
3079	const Decl *Result =
3080	Entry ? Entry.get(getExternalSource()) : computeKeyFunction(*this, RD);
3081
3082	// Store it back if it changed.
3083	if (Entry.isOffset() \|\| Entry.isValid() != bool(Result))
3084	KeyFunctions[RD] = const_cast<Decl*>(Result);
3085
3086	return cast_or_null<CXXMethodDecl>(Result);
3087	}
3088
3089	void ASTContext::setNonKeyFunction(const CXXMethodDecl *Method) {
3090	(0) . __assert_fail ("Method == Method->getFirstDecl() && \"not working with method declaration from class definition\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3091, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Method == Method->getFirstDecl() &&
3091	(0) . __assert_fail ("Method == Method->getFirstDecl() && \"not working with method declaration from class definition\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3091, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "not working with method declaration from class definition");
3092
3093	// Look up the cache entry. Since we're working with the first
3094	// declaration, its parent must be the class definition, which is
3095	// the correct key for the KeyFunctions hash.
3096	const auto &Map = KeyFunctions;
3097	auto I = Map.find(Method->getParent());
3098
3099	// If it's not cached, there's nothing to do.
3100	if (I == Map.end()) return;
3101
3102	// If it is cached, check whether it's the target method, and if so,
3103	// remove it from the cache. Note, the call to 'get' might invalidate
3104	// the iterator and the LazyDeclPtr object within the map.
3105	LazyDeclPtr Ptr = I->second;
3106	if (Ptr.get(getExternalSource()) == Method) {
3107	// FIXME: remember that we did this for module / chained PCH state?
3108	KeyFunctions.erase(Method->getParent());
3109	}
3110	}
3111
3112	static uint64_t getFieldOffset(const ASTContext &C, const FieldDecl *FD) {
3113	const ASTRecordLayout &Layout = C.getASTRecordLayout(FD->getParent());
3114	return Layout.getFieldOffset(FD->getFieldIndex());
3115	}
3116
3117	uint64_t ASTContext::getFieldOffset(const ValueDecl *VD) const {
3118	uint64_t OffsetInBits;
3119	if (const FieldDecl *FD = dyn_cast<FieldDecl>(VD)) {
3120	OffsetInBits = ::getFieldOffset(*this, FD);
3121	} else {
3122	const IndirectFieldDecl *IFD = cast<IndirectFieldDecl>(VD);
3123
3124	OffsetInBits = 0;
3125	for (const NamedDecl *ND : IFD->chain())
3126	OffsetInBits += ::getFieldOffset(*this, cast<FieldDecl>(ND));
3127	}
3128
3129	return OffsetInBits;
3130	}
3131
3132	uint64_t ASTContext::lookupFieldBitOffset(const ObjCInterfaceDecl *OID,
3133	const ObjCImplementationDecl *ID,
3134	const ObjCIvarDecl *Ivar) const {
3135	const ObjCInterfaceDecl *Container = Ivar->getContainingInterface();
3136
3137	// FIXME: We should eliminate the need to have ObjCImplementationDecl passed
3138	// in here; it should never be necessary because that should be the lexical
3139	// decl context for the ivar.
3140
3141	// If we know have an implementation (and the ivar is in it) then
3142	// look up in the implementation layout.
3143	const ASTRecordLayout *RL;
3144	if (ID && declaresSameEntity(ID->getClassInterface(), Container))
3145	RL = &getASTObjCImplementationLayout(ID);
3146	else
3147	RL = &getASTObjCInterfaceLayout(Container);
3148
3149	// Compute field index.
3150	//
3151	// FIXME: The index here is closely tied to how ASTContext::getObjCLayout is
3152	// implemented. This should be fixed to get the information from the layout
3153	// directly.
3154	unsigned Index = 0;
3155
3156	for (const ObjCIvarDecl *IVD = Container->all_declared_ivar_begin();
3157	IVD; IVD = IVD->getNextIvar()) {
3158	if (Ivar == IVD)
3159	break;
3160	++Index;
3161	}
3162	(0) . __assert_fail ("Index < RL->getFieldCount() && \"Ivar is not inside record layout!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3162, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Index < RL->getFieldCount() && "Ivar is not inside record layout!");
3163
3164	return RL->getFieldOffset(Index);
3165	}
3166
3167	/// getObjCLayout - Get or compute information about the layout of the
3168	/// given interface.
3169	///
3170	/// \param Impl - If given, also include the layout of the interface's
3171	/// implementation. This may differ by including synthesized ivars.
3172	const ASTRecordLayout &
3173	ASTContext::getObjCLayout(const ObjCInterfaceDecl *D,
3174	const ObjCImplementationDecl *Impl) const {
3175	// Retrieve the definition
3176	if (D->hasExternalLexicalStorage() && !D->getDefinition())
3177	getExternalSource()->CompleteType(const_cast<ObjCInterfaceDecl*>(D));
3178	D = D->getDefinition();
3179	(0) . __assert_fail ("D && D->isThisDeclarationADefinition() && \"Invalid interface decl!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3179, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(D && D->isThisDeclarationADefinition() && "Invalid interface decl!");
3180
3181	// Look up this layout, if already laid out, return what we have.
3182	const ObjCContainerDecl *Key =
3183	Impl ? (const ObjCContainerDecl) Impl : (const ObjCContainerDecl) D;
3184	if (const ASTRecordLayout *Entry = ObjCLayouts[Key])
3185	return *Entry;
3186
3187	// Add in synthesized ivar count if laying out an implementation.
3188	if (Impl) {
3189	unsigned SynthCount = CountNonClassIvars(D);
3190	// If there aren't any synthesized ivars then reuse the interface
3191	// entry. Note we can't cache this because we simply free all
3192	// entries later; however we shouldn't look up implementations
3193	// frequently.
3194	if (SynthCount == 0)
3195	return getObjCLayout(D, nullptr);
3196	}
3197
3198	ItaniumRecordLayoutBuilder Builder(this, /EmptySubobjects=*/nullptr);
3199	Builder.Layout(D);
3200
3201	const ASTRecordLayout *NewEntry =
3202	new (this) ASTRecordLayout(this, Builder.getSize(),
3203	Builder.Alignment,
3204	Builder.UnadjustedAlignment,
3205	/RequiredAlignment : used by MS-ABI)/
3206	Builder.Alignment,
3207	Builder.getDataSize(),
3208	Builder.FieldOffsets);
3209
3210	ObjCLayouts[Key] = NewEntry;
3211
3212	return *NewEntry;
3213	}
3214
3215	static void PrintOffset(raw_ostream &OS,
3216	CharUnits Offset, unsigned IndentLevel) {
3217	OS << llvm::format("%10" PRId64 " \| ", (int64_t)Offset.getQuantity());
3218	OS.indent(IndentLevel * 2);
3219	}
3220
3221	static void PrintBitFieldOffset(raw_ostream &OS, CharUnits Offset,
3222	unsigned Begin, unsigned Width,
3223	unsigned IndentLevel) {
3224	llvm::SmallString<10> Buffer;
3225	{
3226	llvm::raw_svector_ostream BufferOS(Buffer);
3227	BufferOS << Offset.getQuantity() << ':';
3228	if (Width == 0) {
3229	BufferOS << '-';
3230	} else {
3231	BufferOS << Begin << '-' << (Begin + Width - 1);
3232	}
3233	}
3234
3235	OS << llvm::right_justify(Buffer, 10) << " \| ";
3236	OS.indent(IndentLevel * 2);
3237	}
3238
3239	static void PrintIndentNoOffset(raw_ostream &OS, unsigned IndentLevel) {
3240	OS << " \| ";
3241	OS.indent(IndentLevel * 2);
3242	}
3243
3244	static void DumpRecordLayout(raw_ostream &OS, const RecordDecl *RD,
3245	const ASTContext &C,
3246	CharUnits Offset,
3247	unsigned IndentLevel,
3248	const char* Description,
3249	bool PrintSizeInfo,
3250	bool IncludeVirtualBases) {
3251	const ASTRecordLayout &Layout = C.getASTRecordLayout(RD);
3252	auto CXXRD = dyn_cast<CXXRecordDecl>(RD);
3253
3254	PrintOffset(OS, Offset, IndentLevel);
3255	OS << C.getTypeDeclType(const_cast<RecordDecl*>(RD)).getAsString();
3256	if (Description)
3257	OS << ' ' << Description;
3258	if (CXXRD && CXXRD->isEmpty())
3259	OS << " (empty)";
3260	OS << '\n';
3261
3262	IndentLevel++;
3263
3264	// Dump bases.
3265	if (CXXRD) {
3266	const CXXRecordDecl *PrimaryBase = Layout.getPrimaryBase();
3267	bool HasOwnVFPtr = Layout.hasOwnVFPtr();
3268	bool HasOwnVBPtr = Layout.hasOwnVBPtr();
3269
3270	// Vtable pointer.
3271	if (CXXRD->isDynamicClass() && !PrimaryBase && !isMsLayout(C)) {
3272	PrintOffset(OS, Offset, IndentLevel);
3273	OS << '(' << *RD << " vtable pointer)\n";
3274	} else if (HasOwnVFPtr) {
3275	PrintOffset(OS, Offset, IndentLevel);
3276	// vfptr (for Microsoft C++ ABI)
3277	OS << '(' << *RD << " vftable pointer)\n";
3278	}
3279
3280	// Collect nvbases.
3281	SmallVector<const CXXRecordDecl *, 4> Bases;
3282	for (const CXXBaseSpecifier &Base : CXXRD->bases()) {
3283	(0) . __assert_fail ("!Base.getType()->isDependentType() && \"Cannot layout class with dependent bases.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3284, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(!Base.getType()->isDependentType() &&
3284	(0) . __assert_fail ("!Base.getType()->isDependentType() && \"Cannot layout class with dependent bases.\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3284, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true"> "Cannot layout class with dependent bases.");
3285	if (!Base.isVirtual())
3286	Bases.push_back(Base.getType()->getAsCXXRecordDecl());
3287	}
3288
3289	// Sort nvbases by offset.
3290	std::stable_sort(Bases.begin(), Bases.end(),
3291	[&](const CXXRecordDecl L, const CXXRecordDecl R) {
3292	return Layout.getBaseClassOffset(L) < Layout.getBaseClassOffset(R);
3293	});
3294
3295	// Dump (non-virtual) bases
3296	for (const CXXRecordDecl *Base : Bases) {
3297	CharUnits BaseOffset = Offset + Layout.getBaseClassOffset(Base);
3298	DumpRecordLayout(OS, Base, C, BaseOffset, IndentLevel,
3299	Base == PrimaryBase ? "(primary base)" : "(base)",
3300	/PrintSizeInfo=/false,
3301	/IncludeVirtualBases=/false);
3302	}
3303
3304	// vbptr (for Microsoft C++ ABI)
3305	if (HasOwnVBPtr) {
3306	PrintOffset(OS, Offset + Layout.getVBPtrOffset(), IndentLevel);
3307	OS << '(' << *RD << " vbtable pointer)\n";
3308	}
3309	}
3310
3311	// Dump fields.
3312	uint64_t FieldNo = 0;
3313	for (RecordDecl::field_iterator I = RD->field_begin(),
3314	E = RD->field_end(); I != E; ++I, ++FieldNo) {
3315	const FieldDecl &Field = **I;
3316	uint64_t LocalFieldOffsetInBits = Layout.getFieldOffset(FieldNo);
3317	CharUnits FieldOffset =
3318	Offset + C.toCharUnitsFromBits(LocalFieldOffsetInBits);
3319
3320	// Recursively dump fields of record type.
3321	if (auto RT = Field.getType()->getAs<RecordType>()) {
3322	DumpRecordLayout(OS, RT->getDecl(), C, FieldOffset, IndentLevel,
3323	Field.getName().data(),
3324	/PrintSizeInfo=/false,
3325	/IncludeVirtualBases=/true);
3326	continue;
3327	}
3328
3329	if (Field.isBitField()) {
3330	uint64_t LocalFieldByteOffsetInBits = C.toBits(FieldOffset - Offset);
3331	unsigned Begin = LocalFieldOffsetInBits - LocalFieldByteOffsetInBits;
3332	unsigned Width = Field.getBitWidthValue(C);
3333	PrintBitFieldOffset(OS, FieldOffset, Begin, Width, IndentLevel);
3334	} else {
3335	PrintOffset(OS, FieldOffset, IndentLevel);
3336	}
3337	OS << Field.getType().getAsString() << ' ' << Field << '\n';
3338	}
3339
3340	// Dump virtual bases.
3341	if (CXXRD && IncludeVirtualBases) {
3342	const ASTRecordLayout::VBaseOffsetsMapTy &VtorDisps =
3343	Layout.getVBaseOffsetsMap();
3344
3345	for (const CXXBaseSpecifier &Base : CXXRD->vbases()) {
3346	(0) . __assert_fail ("Base.isVirtual() && \"Found non-virtual class!\"", "/home/seafit/code_projects/clang_source/clang/lib/AST/RecordLayoutBuilder.cpp", 3346, __PRETTY_FUNCTION__))" file_link="../../../include/assert.h.html#88" macro="true">assert(Base.isVirtual() && "Found non-virtual class!");
3347	const CXXRecordDecl *VBase = Base.getType()->getAsCXXRecordDecl();
3348
3349	CharUnits VBaseOffset = Offset + Layout.getVBaseClassOffset(VBase);
3350
3351	if (VtorDisps.find(VBase)->second.hasVtorDisp()) {
3352	PrintOffset(OS, VBaseOffset - CharUnits::fromQuantity(4), IndentLevel);
3353	OS << "(vtordisp for vbase " << *VBase << ")\n";
3354	}
3355
3356	DumpRecordLayout(OS, VBase, C, VBaseOffset, IndentLevel,
3357	VBase == Layout.getPrimaryBase() ?
3358	"(primary virtual base)" : "(virtual base)",
3359	/PrintSizeInfo=/false,
3360	/IncludeVirtualBases=/false);
3361	}
3362	}
3363
3364	if (!PrintSizeInfo) return;
3365
3366	PrintIndentNoOffset(OS, IndentLevel - 1);
3367	OS << "[sizeof=" << Layout.getSize().getQuantity();
3368	if (CXXRD && !isMsLayout(C))
3369	OS << ", dsize=" << Layout.getDataSize().getQuantity();
3370	OS << ", align=" << Layout.getAlignment().getQuantity();
3371
3372	if (CXXRD) {
3373	OS << ",\n";
3374	PrintIndentNoOffset(OS, IndentLevel - 1);
3375	OS << " nvsize=" << Layout.getNonVirtualSize().getQuantity();
3376	OS << ", nvalign=" << Layout.getNonVirtualAlignment().getQuantity();
3377	}
3378	OS << "]\n";
3379	}
3380
3381	void ASTContext::DumpRecordLayout(const RecordDecl *RD,
3382	raw_ostream &OS,
3383	bool Simple) const {
3384	if (!Simple) {
3385	::DumpRecordLayout(OS, RD, *this, CharUnits(), 0, nullptr,
3386	/PrintSizeInfo/true,
3387	/IncludeVirtualBases=/true);
3388	return;
3389	}
3390
3391	// The "simple" format is designed to be parsed by the
3392	// layout-override testing code. There shouldn't be any external
3393	// uses of this format --- when LLDB overrides a layout, it sets up
3394	// the data structures directly --- so feel free to adjust this as
3395	// you like as long as you also update the rudimentary parser for it
3396	// in libFrontend.
3397
3398	const ASTRecordLayout &Info = getASTRecordLayout(RD);
3399	OS << "Type: " << getTypeDeclType(RD).getAsString() << "\n";
3400	OS << "\nLayout: ";
3401	OS << "<ASTRecordLayout\n";
3402	OS << " Size:" << toBits(Info.getSize()) << "\n";
3403	if (!isMsLayout(*this))
3404	OS << " DataSize:" << toBits(Info.getDataSize()) << "\n";
3405	OS << " Alignment:" << toBits(Info.getAlignment()) << "\n";
3406	OS << " FieldOffsets: [";
3407	for (unsigned i = 0, e = Info.getFieldCount(); i != e; ++i) {
3408	if (i) OS << ", ";
3409	OS << Info.getFieldOffset(i);
3410	}
3411	OS << "]>\n";
3412	}
3413

clang::ASTContext::getASTRecordLayout

clang::ASTContext::getCurrentKeyFunction

clang::ASTContext::setNonKeyFunction

clang::ASTContext::getFieldOffset

clang::ASTContext::lookupFieldBitOffset

clang::ASTContext::getObjCLayout

clang::ASTContext::DumpRecordLayout

Clang Project