external/bsd/llvm/dist/clang/lib/AST/RecordLayout.cpp

   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
  20 void ASTRecordLayout::Destroy(ASTContext &Ctx) {
  21   if (FieldOffsets)
  22     Ctx.Deallocate(FieldOffsets);
  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                                  const uint64_t *fieldoffsets,
  36                                  unsigned fieldcount)
  37   : Size(size), DataSize(datasize), Alignment(alignment),
  38     RequiredAlignment(requiredAlignment), FieldOffsets(nullptr),
  39     FieldCount(fieldcount), CXXInfo(nullptr) {
  40   if (FieldCount > 0)  {
  41     FieldOffsets = new (Ctx) uint64_t[FieldCount];
  42     memcpy(FieldOffsets, fieldoffsets, FieldCount * sizeof(*FieldOffsets));
  43   }
  44 }
  45
  46 // Constructor for C++ records.
  47 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx,
  48                                  CharUnits size, CharUnits alignment,
  49                                  CharUnits requiredAlignment,
  50                                  bool hasOwnVFPtr, bool hasExtendableVFPtr,
  51                                  CharUnits vbptroffset,
  52                                  CharUnits datasize,
  53                                  const uint64_t *fieldoffsets,
  54                                  unsigned fieldcount,
  55                                  CharUnits nonvirtualsize,
  56                                  CharUnits nonvirtualalignment,
  57                                  CharUnits SizeOfLargestEmptySubobject,
  58                                  const CXXRecordDecl *PrimaryBase,
  59                                  bool IsPrimaryBaseVirtual,
  60                                  const CXXRecordDecl *BaseSharingVBPtr,
  61                                  bool HasZeroSizedSubObject,
  62                                  bool LeadsWithZeroSizedBase,
  63                                  const BaseOffsetsMapTy& BaseOffsets,
  64                                  const VBaseOffsetsMapTy& VBaseOffsets)
  65   : Size(size), DataSize(datasize), Alignment(alignment),
  66     RequiredAlignment(requiredAlignment), FieldOffsets(nullptr),
  67     FieldCount(fieldcount), CXXInfo(new (Ctx) CXXRecordLayoutInfo)
  68 {
  69   if (FieldCount > 0)  {
  70     FieldOffsets = new (Ctx) uint64_t[FieldCount];
  71     memcpy(FieldOffsets, fieldoffsets, FieldCount * sizeof(*FieldOffsets));
  72   }
  73
  74   CXXInfo->PrimaryBase.setPointer(PrimaryBase);
  75   CXXInfo->PrimaryBase.setInt(IsPrimaryBaseVirtual);
  76   CXXInfo->NonVirtualSize = nonvirtualsize;
  77   CXXInfo->NonVirtualAlignment = nonvirtualalignment;
  78   CXXInfo->SizeOfLargestEmptySubobject = SizeOfLargestEmptySubobject;
  79   CXXInfo->BaseOffsets = BaseOffsets;
  80   CXXInfo->VBaseOffsets = VBaseOffsets;
  81   CXXInfo->HasOwnVFPtr = hasOwnVFPtr;
  82   CXXInfo->VBPtrOffset = vbptroffset;
  83   CXXInfo->HasExtendableVFPtr = hasExtendableVFPtr;
  84   CXXInfo->BaseSharingVBPtr = BaseSharingVBPtr;
  85   CXXInfo->HasZeroSizedSubObject = HasZeroSizedSubObject;
  86   CXXInfo->LeadsWithZeroSizedBase = LeadsWithZeroSizedBase;
  87
  88
  89 #ifndef NDEBUG
  90     if (const CXXRecordDecl *PrimaryBase = getPrimaryBase()) {
  91       if (isPrimaryBaseVirtual()) {
  92         if (Ctx.getTargetInfo().getCXXABI().hasPrimaryVBases()) {
  93           assert(getVBaseClassOffset(PrimaryBase).isZero() &&
  94                  "Primary virtual base must be at offset 0!");
  95         }
  96       } else {
  97         assert(getBaseClassOffset(PrimaryBase).isZero() &&
  98                "Primary base must be at offset 0!");
  99       }
 100     }
 101 #endif
 102 }