contrib/llvm/tools/clang/lib/AST/RecordLayout.cpp

   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
  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
  31 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx, CharUnits size,
  32                                  CharUnits alignment,
  33                                  CharUnits requiredAlignment,
  34                                  CharUnits datasize,
  35                                  ArrayRef<uint64_t> fieldoffsets)
  36     : Size(size), DataSize(datasize), Alignment(alignment),
  37       RequiredAlignment(requiredAlignment) {
  38   FieldOffsets.append(Ctx, fieldoffsets.begin(), fieldoffsets.end());
  39 }
  40
  41 // Constructor for C++ records.
  42 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx,
  43                                  CharUnits size, CharUnits alignment,
  44                                  CharUnits requiredAlignment,
  45                                  bool hasOwnVFPtr, bool hasExtendableVFPtr,
  46                                  CharUnits vbptroffset,
  47                                  CharUnits datasize,
  48                                  ArrayRef<uint64_t> fieldoffsets,
  49                                  CharUnits nonvirtualsize,
  50                                  CharUnits nonvirtualalignment,
  51                                  CharUnits SizeOfLargestEmptySubobject,
  52                                  const CXXRecordDecl *PrimaryBase,
  53                                  bool IsPrimaryBaseVirtual,
  54                                  const CXXRecordDecl *BaseSharingVBPtr,
  55                                  bool EndsWithZeroSizedObject,
  56                                  bool LeadsWithZeroSizedBase,
  57                                  const BaseOffsetsMapTy& BaseOffsets,
  58                                  const VBaseOffsetsMapTy& VBaseOffsets)
  59   : Size(size), DataSize(datasize), Alignment(alignment),
  60     RequiredAlignment(requiredAlignment), CXXInfo(new (Ctx) CXXRecordLayoutInfo)
  61 {
  62   FieldOffsets.append(Ctx, fieldoffsets.begin(), fieldoffsets.end());
  63
  64   CXXInfo->PrimaryBase.setPointer(PrimaryBase);
  65   CXXInfo->PrimaryBase.setInt(IsPrimaryBaseVirtual);
  66   CXXInfo->NonVirtualSize = nonvirtualsize;
  67   CXXInfo->NonVirtualAlignment = nonvirtualalignment;
  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 }