1//===- RecordLayout.cpp - Layout information for a struct/union -----------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines the RecordLayout interface.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/AST/RecordLayout.h"
14#include "clang/AST/ASTContext.h"
15#include "clang/Basic/TargetCXXABI.h"
16#include "clang/Basic/TargetInfo.h"
17#include <cassert>
18
19using namespace clang;
20
21void ASTRecordLayout::Destroy(ASTContext &Ctx) {
22 if (CXXInfo) {
23 CXXInfo->~CXXRecordLayoutInfo();
24 Ctx.Deallocate(Ptr: CXXInfo);
25 }
26 this->~ASTRecordLayout();
27 Ctx.Deallocate(Ptr: this);
28}
29
30ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx, CharUnits size,
31 CharUnits alignment,
32 CharUnits preferredAlignment,
33 CharUnits unadjustedAlignment,
34 CharUnits requiredAlignment,
35 CharUnits datasize,
36 ArrayRef<uint64_t> fieldoffsets)
37 : Size(size), DataSize(datasize), Alignment(alignment),
38 PreferredAlignment(preferredAlignment),
39 UnadjustedAlignment(unadjustedAlignment),
40 RequiredAlignment(requiredAlignment) {
41 FieldOffsets.append(C: Ctx, in_start: fieldoffsets.begin(), in_end: fieldoffsets.end());
42}
43
44// Constructor for C++ records.
45ASTRecordLayout::ASTRecordLayout(
46 const ASTContext &Ctx, CharUnits size, CharUnits alignment,
47 CharUnits preferredAlignment, CharUnits unadjustedAlignment,
48 CharUnits requiredAlignment, bool hasOwnVFPtr, bool hasExtendableVFPtr,
49 CharUnits vbptroffset, CharUnits datasize, ArrayRef<uint64_t> fieldoffsets,
50 CharUnits nonvirtualsize, CharUnits nonvirtualalignment,
51 CharUnits preferrednvalignment, CharUnits SizeOfLargestEmptySubobject,
52 const CXXRecordDecl *PrimaryBase, bool IsPrimaryBaseVirtual,
53 const CXXRecordDecl *BaseSharingVBPtr, bool EndsWithZeroSizedObject,
54 bool LeadsWithZeroSizedBase, const BaseOffsetsMapTy &BaseOffsets,
55 const VBaseOffsetsMapTy &VBaseOffsets)
56 : Size(size), DataSize(datasize), Alignment(alignment),
57 PreferredAlignment(preferredAlignment),
58 UnadjustedAlignment(unadjustedAlignment),
59 RequiredAlignment(requiredAlignment),
60 CXXInfo(new (Ctx) CXXRecordLayoutInfo) {
61 FieldOffsets.append(C: Ctx, in_start: fieldoffsets.begin(), in_end: fieldoffsets.end());
62
63 CXXInfo->PrimaryBase.setPointer(PrimaryBase);
64 CXXInfo->PrimaryBase.setInt(IsPrimaryBaseVirtual);
65 CXXInfo->NonVirtualSize = nonvirtualsize;
66 CXXInfo->NonVirtualAlignment = nonvirtualalignment;
67 CXXInfo->PreferredNVAlignment = preferrednvalignment;
68 CXXInfo->SizeOfLargestEmptySubobject = SizeOfLargestEmptySubobject;
69 CXXInfo->BaseOffsets = BaseOffsets;
70 CXXInfo->VBaseOffsets = VBaseOffsets;
71 CXXInfo->HasOwnVFPtr = hasOwnVFPtr;
72 CXXInfo->VBPtrOffset = vbptroffset;
73 CXXInfo->HasExtendableVFPtr = hasExtendableVFPtr;
74 CXXInfo->BaseSharingVBPtr = BaseSharingVBPtr;
75 CXXInfo->EndsWithZeroSizedObject = EndsWithZeroSizedObject;
76 CXXInfo->LeadsWithZeroSizedBase = LeadsWithZeroSizedBase;
77
78#ifndef NDEBUG
79 if (const CXXRecordDecl *PrimaryBase = getPrimaryBase()) {
80 if (isPrimaryBaseVirtual()) {
81 if (Ctx.getTargetInfo().getCXXABI().hasPrimaryVBases()) {
82 assert(getVBaseClassOffset(PrimaryBase).isZero() &&
83 "Primary virtual base must be at offset 0!");
84 }
85 } else {
86 assert(getBaseClassOffset(PrimaryBase).isZero() &&
87 "Primary base must be at offset 0!");
88 }
89 }
90#endif
91}
92

source code of clang/lib/AST/RecordLayout.cpp