• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===-- RecordLayout.cpp - Layout information for a struct/union -*- C++ -*-==//
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/ASTContext.h"
15 #include "clang/AST/RecordLayout.h"
16 #include "clang/Basic/TargetInfo.h"
17 
18 using namespace clang;
19 
Destroy(ASTContext & Ctx)20 void ASTRecordLayout::Destroy(ASTContext &Ctx) {
21   if (FieldOffsets)
22     Ctx.Deallocate(FieldOffsets);
23   if (CXXInfo) {
24     Ctx.Deallocate(CXXInfo);
25     CXXInfo->~CXXRecordLayoutInfo();
26   }
27   this->~ASTRecordLayout();
28   Ctx.Deallocate(this);
29 }
30 
ASTRecordLayout(const ASTContext & Ctx,CharUnits size,CharUnits alignment,CharUnits datasize,const uint64_t * fieldoffsets,unsigned fieldcount)31 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx, CharUnits size,
32                                  CharUnits alignment, CharUnits datasize,
33                                  const uint64_t *fieldoffsets,
34                                  unsigned fieldcount)
35   : Size(size), DataSize(datasize), Alignment(alignment), FieldOffsets(0),
36     FieldCount(fieldcount), CXXInfo(0) {
37   if (FieldCount > 0)  {
38     FieldOffsets = new (Ctx) uint64_t[FieldCount];
39     memcpy(FieldOffsets, fieldoffsets, FieldCount * sizeof(*FieldOffsets));
40   }
41 }
42 
43 // Constructor for C++ records.
ASTRecordLayout(const ASTContext & Ctx,CharUnits size,CharUnits alignment,bool hasOwnVFPtr,CharUnits vbptroffset,CharUnits datasize,const uint64_t * fieldoffsets,unsigned fieldcount,CharUnits nonvirtualsize,CharUnits nonvirtualalign,CharUnits SizeOfLargestEmptySubobject,const CXXRecordDecl * PrimaryBase,bool IsPrimaryBaseVirtual,const BaseOffsetsMapTy & BaseOffsets,const VBaseOffsetsMapTy & VBaseOffsets)44 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx,
45                                  CharUnits size, CharUnits alignment,
46                                  bool hasOwnVFPtr, CharUnits vbptroffset,
47                                  CharUnits datasize,
48                                  const uint64_t *fieldoffsets,
49                                  unsigned fieldcount,
50                                  CharUnits nonvirtualsize,
51                                  CharUnits nonvirtualalign,
52                                  CharUnits SizeOfLargestEmptySubobject,
53                                  const CXXRecordDecl *PrimaryBase,
54                                  bool IsPrimaryBaseVirtual,
55                                  const BaseOffsetsMapTy& BaseOffsets,
56                                  const VBaseOffsetsMapTy& VBaseOffsets)
57   : Size(size), DataSize(datasize), Alignment(alignment), FieldOffsets(0),
58     FieldCount(fieldcount), CXXInfo(new (Ctx) CXXRecordLayoutInfo)
59 {
60   if (FieldCount > 0)  {
61     FieldOffsets = new (Ctx) uint64_t[FieldCount];
62     memcpy(FieldOffsets, fieldoffsets, FieldCount * sizeof(*FieldOffsets));
63   }
64 
65   CXXInfo->PrimaryBase.setPointer(PrimaryBase);
66   CXXInfo->PrimaryBase.setInt(IsPrimaryBaseVirtual);
67   CXXInfo->NonVirtualSize = nonvirtualsize;
68   CXXInfo->NonVirtualAlign = nonvirtualalign;
69   CXXInfo->SizeOfLargestEmptySubobject = SizeOfLargestEmptySubobject;
70   CXXInfo->BaseOffsets = BaseOffsets;
71   CXXInfo->VBaseOffsets = VBaseOffsets;
72   CXXInfo->HasOwnVFPtr = hasOwnVFPtr;
73   CXXInfo->VBPtrOffset = vbptroffset;
74 
75 #ifndef NDEBUG
76     if (const CXXRecordDecl *PrimaryBase = getPrimaryBase()) {
77       if (isPrimaryBaseVirtual()) {
78         if (Ctx.getTargetInfo().getCXXABI().hasPrimaryVBases()) {
79           assert(getVBaseClassOffset(PrimaryBase).isZero() &&
80                  "Primary virtual base must be at offset 0!");
81         }
82       } else {
83         assert(getBaseClassOffset(PrimaryBase).isZero() &&
84                "Primary base must be at offset 0!");
85       }
86     }
87 #endif
88 }
89