1 //===- RecordLayout.cpp - Layout information for a struct/union -----------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the RecordLayout interface.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/AST/RecordLayout.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/Basic/TargetCXXABI.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include <cassert>
19
20 using namespace clang;
21
Destroy(ASTContext & Ctx)22 void ASTRecordLayout::Destroy(ASTContext &Ctx) {
23 if (CXXInfo) {
24 CXXInfo->~CXXRecordLayoutInfo();
25 Ctx.Deallocate(CXXInfo);
26 }
27 this->~ASTRecordLayout();
28 Ctx.Deallocate(this);
29 }
30
ASTRecordLayout(const ASTContext & Ctx,CharUnits size,CharUnits alignment,CharUnits unadjustedAlignment,CharUnits requiredAlignment,CharUnits datasize,ArrayRef<uint64_t> fieldoffsets)31 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx, CharUnits size,
32 CharUnits alignment,
33 CharUnits unadjustedAlignment,
34 CharUnits requiredAlignment,
35 CharUnits datasize,
36 ArrayRef<uint64_t> fieldoffsets)
37 : Size(size), DataSize(datasize), Alignment(alignment),
38 UnadjustedAlignment(unadjustedAlignment),
39 RequiredAlignment(requiredAlignment) {
40 FieldOffsets.append(Ctx, fieldoffsets.begin(), fieldoffsets.end());
41 }
42
43 // Constructor for C++ records.
ASTRecordLayout(const ASTContext & Ctx,CharUnits size,CharUnits alignment,CharUnits unadjustedAlignment,CharUnits requiredAlignment,bool hasOwnVFPtr,bool hasExtendableVFPtr,CharUnits vbptroffset,CharUnits datasize,ArrayRef<uint64_t> fieldoffsets,CharUnits nonvirtualsize,CharUnits nonvirtualalignment,CharUnits SizeOfLargestEmptySubobject,const CXXRecordDecl * PrimaryBase,bool IsPrimaryBaseVirtual,const CXXRecordDecl * BaseSharingVBPtr,bool EndsWithZeroSizedObject,bool LeadsWithZeroSizedBase,const BaseOffsetsMapTy & BaseOffsets,const VBaseOffsetsMapTy & VBaseOffsets)44 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx,
45 CharUnits size, CharUnits alignment,
46 CharUnits unadjustedAlignment,
47 CharUnits requiredAlignment,
48 bool hasOwnVFPtr, bool hasExtendableVFPtr,
49 CharUnits vbptroffset,
50 CharUnits datasize,
51 ArrayRef<uint64_t> fieldoffsets,
52 CharUnits nonvirtualsize,
53 CharUnits nonvirtualalignment,
54 CharUnits SizeOfLargestEmptySubobject,
55 const CXXRecordDecl *PrimaryBase,
56 bool IsPrimaryBaseVirtual,
57 const CXXRecordDecl *BaseSharingVBPtr,
58 bool EndsWithZeroSizedObject,
59 bool LeadsWithZeroSizedBase,
60 const BaseOffsetsMapTy& BaseOffsets,
61 const VBaseOffsetsMapTy& VBaseOffsets)
62 : Size(size), DataSize(datasize), Alignment(alignment),
63 UnadjustedAlignment(unadjustedAlignment),
64 RequiredAlignment(requiredAlignment), CXXInfo(new (Ctx) CXXRecordLayoutInfo)
65 {
66 FieldOffsets.append(Ctx, fieldoffsets.begin(), fieldoffsets.end());
67
68 CXXInfo->PrimaryBase.setPointer(PrimaryBase);
69 CXXInfo->PrimaryBase.setInt(IsPrimaryBaseVirtual);
70 CXXInfo->NonVirtualSize = nonvirtualsize;
71 CXXInfo->NonVirtualAlignment = nonvirtualalignment;
72 CXXInfo->SizeOfLargestEmptySubobject = SizeOfLargestEmptySubobject;
73 CXXInfo->BaseOffsets = BaseOffsets;
74 CXXInfo->VBaseOffsets = VBaseOffsets;
75 CXXInfo->HasOwnVFPtr = hasOwnVFPtr;
76 CXXInfo->VBPtrOffset = vbptroffset;
77 CXXInfo->HasExtendableVFPtr = hasExtendableVFPtr;
78 CXXInfo->BaseSharingVBPtr = BaseSharingVBPtr;
79 CXXInfo->EndsWithZeroSizedObject = EndsWithZeroSizedObject;
80 CXXInfo->LeadsWithZeroSizedBase = LeadsWithZeroSizedBase;
81
82 #ifndef NDEBUG
83 if (const CXXRecordDecl *PrimaryBase = getPrimaryBase()) {
84 if (isPrimaryBaseVirtual()) {
85 if (Ctx.getTargetInfo().getCXXABI().hasPrimaryVBases()) {
86 assert(getVBaseClassOffset(PrimaryBase).isZero() &&
87 "Primary virtual base must be at offset 0!");
88 }
89 } else {
90 assert(getBaseClassOffset(PrimaryBase).isZero() &&
91 "Primary base must be at offset 0!");
92 }
93 }
94 #endif
95 }
96