contrib/llvm/tools/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     Ctx.Deallocate(CXXInfo);
  25     CXXInfo->~CXXRecordLayoutInfo();
  26   }
  27   this->~ASTRecordLayout();
  28   Ctx.Deallocate(this);
  29 }
  30
  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), FieldOffsets(0), Alignment(alignment),
  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.
  44 ASTRecordLayout::ASTRecordLayout(const ASTContext &Ctx,
  45                                  CharUnits size, CharUnits alignment,
  46                                  CharUnits vbptroffset, CharUnits datasize,
  47                                  const uint64_t *fieldoffsets,
  48                                  unsigned fieldcount,
  49                                  CharUnits nonvirtualsize,
  50                                  CharUnits nonvirtualalign,
  51                                  CharUnits SizeOfLargestEmptySubobject,
  52                                  const CXXRecordDecl *PrimaryBase,
  53                                  bool IsPrimaryBaseVirtual,
  54                                  const BaseOffsetsMapTy& BaseOffsets,
  55                                  const BaseOffsetsMapTy& VBaseOffsets)
  56   : Size(size), DataSize(datasize), FieldOffsets(0), Alignment(alignment),
  57     FieldCount(fieldcount), CXXInfo(new (Ctx) CXXRecordLayoutInfo)
  58 {
  59   if (FieldCount > 0)  {
  60     FieldOffsets = new (Ctx) uint64_t[FieldCount];
  61     memcpy(FieldOffsets, fieldoffsets, FieldCount * sizeof(*FieldOffsets));
  62   }
  63
  64   CXXInfo->PrimaryBase.setPointer(PrimaryBase);
  65   CXXInfo->PrimaryBase.setInt(IsPrimaryBaseVirtual);
  66   CXXInfo->NonVirtualSize = nonvirtualsize;
  67   CXXInfo->NonVirtualAlign = nonvirtualalign;
  68   CXXInfo->SizeOfLargestEmptySubobject = SizeOfLargestEmptySubobject;
  69   CXXInfo->BaseOffsets = BaseOffsets;
  70   CXXInfo->VBaseOffsets = VBaseOffsets;
  71   CXXInfo->VBPtrOffset = vbptroffset;
  72
  73 #ifndef NDEBUG
  74     if (const CXXRecordDecl *PrimaryBase = getPrimaryBase()) {
  75       if (isPrimaryBaseVirtual()) {
  76         // Microsoft ABI doesn't have primary virtual base
  77         if (Ctx.getTargetInfo().getCXXABI() != CXXABI_Microsoft) {
  78         assert(getVBaseClassOffset(PrimaryBase).isZero() &&
  79                "Primary virtual base must be at offset 0!");
  80         }
  81       } else {
  82         assert(getBaseClassOffsetInBits(PrimaryBase) == 0 &&
  83                "Primary base must be at offset 0!");
  84       }
  85     }
  86 #endif
  87 }