C++ QualType::isVolatileQualified方法代码示例

/// getOrCreateCVRType - Get the CVR qualified type from the cache or create 
/// a new one if necessary.
llvm::DIType CGDebugInfo::CreateCVRType(QualType Ty, llvm::DICompileUnit Unit) {
  // We will create one Derived type for one qualifier and recurse to handle any
  // additional ones.
  llvm::DIType FromTy;
  unsigned Tag;
  if (Ty.isConstQualified()) {
    Tag = llvm::dwarf::DW_TAG_const_type;
    Ty.removeConst(); 
    FromTy = getOrCreateType(Ty, Unit);
  } else if (Ty.isVolatileQualified()) {
    Tag = llvm::dwarf::DW_TAG_volatile_type;
    Ty.removeVolatile(); 
    FromTy = getOrCreateType(Ty, Unit);
  } else {
    assert(Ty.isRestrictQualified() && "Unknown type qualifier for debug info");
    Tag = llvm::dwarf::DW_TAG_restrict_type;
    Ty.removeRestrict(); 
    FromTy = getOrCreateType(Ty, Unit);
  }
  
  // No need to fill in the Name, Line, Size, Alignment, Offset in case of
  // CVR derived types.
  return DebugFactory.CreateDerivedType(Tag, Unit, "", llvm::DICompileUnit(),
                                        0, 0, 0, 0, 0, FromTy);
}

void CodeGenFunction::EmitVarDecl(const DeclExpr* D) {
    // TODO arrays types?
    QualType qt = D->getType();
    llvm::AllocaInst* inst = Builder.CreateAlloca(CGM.ConvertType(qt.getTypePtr()), 0, D->getName());
    // TODO smart alignment
    inst->setAlignment(D->getType()->getWidth());
    const Expr* I = D->getInitValue();
    if (I) {
        llvm::Value* val = EmitExpr(I);
        Builder.CreateStore(val, inst, qt.isVolatileQualified());
    }
}

QualType TypeResolver::resolveUnresolved(QualType Q) const {
    const Type* T = Q.getTypePtr();
    switch (Q->getTypeClass()) {
    case TC_BUILTIN:
        return Q;
    case TC_POINTER:
        {
            // Dont return new type if not needed
            const PointerType* P = cast<PointerType>(T);
            QualType t1 = P->getPointeeType();
            QualType Result = resolveUnresolved(t1);
            if (t1 == Result) return Q;
            // TODO qualifiers
            return typeContext.getPointerType(Result);
        }
    case TC_ARRAY:
        {
            const ArrayType* A = cast<ArrayType>(T);
            QualType t1 = A->getElementType();
            QualType Result = resolveUnresolved(t1);
            if (t1 == Result) return Q;
            // TODO qualifiers
            return typeContext.getArrayType(Result, A->getSizeExpr(), false, A->isIncremental());

        }
    case TC_UNRESOLVED:
        {
            const UnresolvedType* U = cast<UnresolvedType>(T);
            TypeDecl* TD = U->getDecl();
            assert(TD);
            QualType result = TD->getType();
            if (Q.isConstQualified()) result.addConst();
            if (Q.isVolatileQualified()) result.addVolatile();
            return result;
        }
    case TC_ALIAS:
    case TC_STRUCT:
    case TC_ENUM:
    case TC_FUNCTION:
        return Q;
    case TC_MODULE:
        assert(0 && "TBD");
        return Q;
    }
    return Q;
}

/// Emit an alloca (or GlobalValue depending on target) 
/// for the specified parameter and set up LocalDeclMap.
void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg) {
  // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
  assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
         "Invalid argument to EmitParmDecl");
  QualType Ty = D.getType();
  
  llvm::Value *DeclPtr;
  if (!Ty->isConstantSizeType()) {
    // Variable sized values always are passed by-reference.
    DeclPtr = Arg;
  } else {
    // A fixed sized single-value variable becomes an alloca in the entry block.
    const llvm::Type *LTy = ConvertTypeForMem(Ty);
    if (LTy->isSingleValueType()) {
      // TODO: Alignment
      std::string Name = D.getNameAsString();
      Name += ".addr";
      DeclPtr = CreateTempAlloca(LTy);
      DeclPtr->setName(Name.c_str());
      
      // Store the initial value into the alloca.
      EmitStoreOfScalar(Arg, DeclPtr, Ty.isVolatileQualified(), Ty);
    } else {
      // Otherwise, if this is an aggregate, just use the input pointer.
      DeclPtr = Arg;
    }
    Arg->setName(D.getNameAsString());
  }

  llvm::Value *&DMEntry = LocalDeclMap[&D];
  assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
  DMEntry = DeclPtr;

  // Emit debug info for param declaration.
  if (CGDebugInfo *DI = getDebugInfo()) {
    DI->setLocation(D.getLocation());
    DI->EmitDeclareOfArgVariable(&D, DeclPtr, Builder);
  }
}

void CodeGenFunction::EmitCallAndReturnForThunk(llvm::Constant *CalleePtr,
                                                const ThunkInfo *Thunk) {
  assert(isa<CXXMethodDecl>(CurGD.getDecl()) &&
         "Please use a new CGF for this thunk");
  const CXXMethodDecl *MD = cast<CXXMethodDecl>(CurGD.getDecl());

  // Adjust the 'this' pointer if necessary
  llvm::Value *AdjustedThisPtr =
    Thunk ? CGM.getCXXABI().performThisAdjustment(
                          *this, LoadCXXThisAddress(), Thunk->This)
          : LoadCXXThis();

  if (CurFnInfo->usesInAlloca()) {
    // We don't handle return adjusting thunks, because they require us to call
    // the copy constructor.  For now, fall through and pretend the return
    // adjustment was empty so we don't crash.
    if (Thunk && !Thunk->Return.isEmpty()) {
      CGM.ErrorUnsupported(
          MD, "non-trivial argument copy for return-adjusting thunk");
    }
    EmitMustTailThunk(MD, AdjustedThisPtr, CalleePtr);
    return;
  }

  // Start building CallArgs.
  CallArgList CallArgs;
  QualType ThisType = MD->getThisType(getContext());
  CallArgs.add(RValue::get(AdjustedThisPtr), ThisType);

  if (isa<CXXDestructorDecl>(MD))
    CGM.getCXXABI().adjustCallArgsForDestructorThunk(*this, CurGD, CallArgs);

#ifndef NDEBUG
  unsigned PrefixArgs = CallArgs.size() - 1;
#endif
  // Add the rest of the arguments.
  for (const ParmVarDecl *PD : MD->parameters())
    EmitDelegateCallArg(CallArgs, PD, SourceLocation());

  const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();

#ifndef NDEBUG
  const CGFunctionInfo &CallFnInfo = CGM.getTypes().arrangeCXXMethodCall(
      CallArgs, FPT, RequiredArgs::forPrototypePlus(FPT, 1, MD), PrefixArgs);
  assert(CallFnInfo.getRegParm() == CurFnInfo->getRegParm() &&
         CallFnInfo.isNoReturn() == CurFnInfo->isNoReturn() &&
         CallFnInfo.getCallingConvention() == CurFnInfo->getCallingConvention());
  assert(isa<CXXDestructorDecl>(MD) || // ignore dtor return types
         similar(CallFnInfo.getReturnInfo(), CallFnInfo.getReturnType(),
                 CurFnInfo->getReturnInfo(), CurFnInfo->getReturnType()));
  assert(CallFnInfo.arg_size() == CurFnInfo->arg_size());
  for (unsigned i = 0, e = CurFnInfo->arg_size(); i != e; ++i)
    assert(similar(CallFnInfo.arg_begin()[i].info,
                   CallFnInfo.arg_begin()[i].type,
                   CurFnInfo->arg_begin()[i].info,
                   CurFnInfo->arg_begin()[i].type));
#endif

  // Determine whether we have a return value slot to use.
  QualType ResultType = CGM.getCXXABI().HasThisReturn(CurGD)
                            ? ThisType
                            : CGM.getCXXABI().hasMostDerivedReturn(CurGD)
                                  ? CGM.getContext().VoidPtrTy
                                  : FPT->getReturnType();
  ReturnValueSlot Slot;
  if (!ResultType->isVoidType() &&
      CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect &&
      !hasScalarEvaluationKind(CurFnInfo->getReturnType()))
    Slot = ReturnValueSlot(ReturnValue, ResultType.isVolatileQualified());

  // Now emit our call.
  llvm::Instruction *CallOrInvoke;
  CGCallee Callee = CGCallee::forDirect(CalleePtr, MD);
  RValue RV = EmitCall(*CurFnInfo, Callee, Slot, CallArgs, &CallOrInvoke);

  // Consider return adjustment if we have ThunkInfo.
  if (Thunk && !Thunk->Return.isEmpty())
    RV = PerformReturnAdjustment(*this, ResultType, RV, *Thunk);
  else if (llvm::CallInst* Call = dyn_cast<llvm::CallInst>(CallOrInvoke))
    Call->setTailCallKind(llvm::CallInst::TCK_Tail);

  // Emit return.
  if (!ResultType->isVoidType() && Slot.isNull())
    CGM.getCXXABI().EmitReturnFromThunk(*this, RV, ResultType);

  // Disable the final ARC autorelease.
  AutoreleaseResult = false;

  FinishThunk();
}

void CodeGenFunction::EmitCallAndReturnForThunk(GlobalDecl GD,
                                                llvm::Value *Callee,
                                                const ThunkInfo *Thunk) {
  assert(isa<CXXMethodDecl>(CurGD.getDecl()) &&
         "Please use a new CGF for this thunk");
  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());

  // Adjust the 'this' pointer if necessary
  llvm::Value *AdjustedThisPtr = Thunk ? CGM.getCXXABI().performThisAdjustment(
                                             *this, LoadCXXThis(), Thunk->This)
                                       : LoadCXXThis();

  // Start building CallArgs.
  CallArgList CallArgs;
  QualType ThisType = MD->getThisType(getContext());
  CallArgs.add(RValue::get(AdjustedThisPtr), ThisType);

  if (isa<CXXDestructorDecl>(MD))
    CGM.getCXXABI().adjustCallArgsForDestructorThunk(*this, GD, CallArgs);

  // Add the rest of the arguments.
  for (FunctionDecl::param_const_iterator I = MD->param_begin(),
       E = MD->param_end(); I != E; ++I)
    EmitDelegateCallArg(CallArgs, *I, (*I)->getLocStart());

  const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();

#ifndef NDEBUG
  const CGFunctionInfo &CallFnInfo =
    CGM.getTypes().arrangeCXXMethodCall(CallArgs, FPT,
                                       RequiredArgs::forPrototypePlus(FPT, 1));
  assert(CallFnInfo.getRegParm() == CurFnInfo->getRegParm() &&
         CallFnInfo.isNoReturn() == CurFnInfo->isNoReturn() &&
         CallFnInfo.getCallingConvention() == CurFnInfo->getCallingConvention());
  assert(isa<CXXDestructorDecl>(MD) || // ignore dtor return types
         similar(CallFnInfo.getReturnInfo(), CallFnInfo.getReturnType(),
                 CurFnInfo->getReturnInfo(), CurFnInfo->getReturnType()));
  assert(CallFnInfo.arg_size() == CurFnInfo->arg_size());
  for (unsigned i = 0, e = CurFnInfo->arg_size(); i != e; ++i)
    assert(similar(CallFnInfo.arg_begin()[i].info,
                   CallFnInfo.arg_begin()[i].type,
                   CurFnInfo->arg_begin()[i].info,
                   CurFnInfo->arg_begin()[i].type));
#endif

  // Determine whether we have a return value slot to use.
  QualType ResultType =
      CGM.getCXXABI().HasThisReturn(GD) ? ThisType : FPT->getReturnType();
  ReturnValueSlot Slot;
  if (!ResultType->isVoidType() &&
      CurFnInfo->getReturnInfo().getKind() == ABIArgInfo::Indirect &&
      !hasScalarEvaluationKind(CurFnInfo->getReturnType()))
    Slot = ReturnValueSlot(ReturnValue, ResultType.isVolatileQualified());
  
  // Now emit our call.
  RValue RV = EmitCall(*CurFnInfo, Callee, Slot, CallArgs, MD);
  
  // Consider return adjustment if we have ThunkInfo.
  if (Thunk && !Thunk->Return.isEmpty())
    RV = PerformReturnAdjustment(*this, ResultType, RV, *Thunk);

  // Emit return.
  if (!ResultType->isVoidType() && Slot.isNull())
    CGM.getCXXABI().EmitReturnFromThunk(*this, RV, ResultType);

  // Disable the final ARC autorelease.
  AutoreleaseResult = false;

  FinishFunction();
}

QualType Sema::CheckPointerToMemberOperands(
  Expr *&lex, Expr *&rex, SourceLocation Loc, bool isIndirect)
{
  const char *OpSpelling = isIndirect ? "->*" : ".*";
  // C++ 5.5p2
  //   The binary operator .* [p3: ->*] binds its second operand, which shall
  //   be of type "pointer to member of T" (where T is a completely-defined
  //   class type) [...]
  QualType RType = rex->getType();
  const MemberPointerType *MemPtr = RType->getAsMemberPointerType();
  if (!MemPtr) {
    Diag(Loc, diag::err_bad_memptr_rhs)
      << OpSpelling << RType << rex->getSourceRange();
    return QualType();
  } else if (RequireCompleteType(Loc, QualType(MemPtr->getClass(), 0),
                                 diag::err_memptr_rhs_incomplete,
                                 rex->getSourceRange()))
    return QualType();

  QualType Class(MemPtr->getClass(), 0);

  // C++ 5.5p2
  //   [...] to its first operand, which shall be of class T or of a class of
  //   which T is an unambiguous and accessible base class. [p3: a pointer to
  //   such a class]
  QualType LType = lex->getType();
  if (isIndirect) {
    if (const PointerType *Ptr = LType->getAsPointerType())
      LType = Ptr->getPointeeType().getNonReferenceType();
    else {
      Diag(Loc, diag::err_bad_memptr_lhs)
        << OpSpelling << 1 << LType << lex->getSourceRange();
      return QualType();
    }
  }

  if (Context.getCanonicalType(Class).getUnqualifiedType() !=
      Context.getCanonicalType(LType).getUnqualifiedType()) {
    BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/false,
                    /*DetectVirtual=*/false);
    // FIXME: Would it be useful to print full ambiguity paths,
    // or is that overkill?
    if (!IsDerivedFrom(LType, Class, Paths) ||
        Paths.isAmbiguous(Context.getCanonicalType(Class))) {
      Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
        << (int)isIndirect << lex->getType() << lex->getSourceRange();
      return QualType();
    }
  }

  // C++ 5.5p2
  //   The result is an object or a function of the type specified by the
  //   second operand.
  // The cv qualifiers are the union of those in the pointer and the left side,
  // in accordance with 5.5p5 and 5.2.5.
  // FIXME: This returns a dereferenced member function pointer as a normal
  // function type. However, the only operation valid on such functions is
  // calling them. There's also a GCC extension to get a function pointer to
  // the thing, which is another complication, because this type - unlike the
  // type that is the result of this expression - takes the class as the first
  // argument.
  // We probably need a "MemberFunctionClosureType" or something like that.
  QualType Result = MemPtr->getPointeeType();
  if (LType.isConstQualified())
    Result.addConst();
  if (LType.isVolatileQualified())
    Result.addVolatile();
  return Result;
}

void CodeGenFunction::GenerateThunk(llvm::Function *Fn,
                                    const CGFunctionInfo &FnInfo,
                                    GlobalDecl GD, const ThunkInfo &Thunk) {
  const CXXMethodDecl *MD = cast<CXXMethodDecl>(GD.getDecl());
  const FunctionProtoType *FPT = MD->getType()->getAs<FunctionProtoType>();
  QualType ResultType = FPT->getResultType();
  QualType ThisType = MD->getThisType(getContext());

  FunctionArgList FunctionArgs;

  // FIXME: It would be nice if more of this code could be shared with 
  // CodeGenFunction::GenerateCode.

  // Create the implicit 'this' parameter declaration.
  CurGD = GD;
  CGM.getCXXABI().BuildInstanceFunctionParams(*this, ResultType, FunctionArgs);

  // Add the rest of the parameters.
  for (FunctionDecl::param_const_iterator I = MD->param_begin(),
       E = MD->param_end(); I != E; ++I) {
    ParmVarDecl *Param = *I;
    
    FunctionArgs.push_back(Param);
  }
  
  StartFunction(GlobalDecl(), ResultType, Fn, FnInfo, FunctionArgs,
                SourceLocation());

  CGM.getCXXABI().EmitInstanceFunctionProlog(*this);
  CXXThisValue = CXXABIThisValue;

  // Adjust the 'this' pointer if necessary.
  llvm::Value *AdjustedThisPtr = 
    PerformTypeAdjustment(*this, LoadCXXThis(), 
                          Thunk.This.NonVirtual, 
                          Thunk.This.VCallOffsetOffset,
                          /*IsReturnAdjustment*/false);
  
  CallArgList CallArgs;
  
  // Add our adjusted 'this' pointer.
  CallArgs.add(RValue::get(AdjustedThisPtr), ThisType);

  // Add the rest of the parameters.
  for (FunctionDecl::param_const_iterator I = MD->param_begin(),
       E = MD->param_end(); I != E; ++I) {
    ParmVarDecl *param = *I;
    EmitDelegateCallArg(CallArgs, param);
  }

  // Get our callee.
  llvm::Type *Ty =
    CGM.getTypes().GetFunctionType(CGM.getTypes().arrangeGlobalDeclaration(GD));
  llvm::Value *Callee = CGM.GetAddrOfFunction(GD, Ty, /*ForVTable=*/true);

#ifndef NDEBUG
  const CGFunctionInfo &CallFnInfo =
    CGM.getTypes().arrangeCXXMethodCall(CallArgs, FPT,
                                       RequiredArgs::forPrototypePlus(FPT, 1));
  assert(CallFnInfo.getRegParm() == FnInfo.getRegParm() &&
         CallFnInfo.isNoReturn() == FnInfo.isNoReturn() &&
         CallFnInfo.getCallingConvention() == FnInfo.getCallingConvention());
  assert(isa<CXXDestructorDecl>(MD) || // ignore dtor return types
         similar(CallFnInfo.getReturnInfo(), CallFnInfo.getReturnType(),
                 FnInfo.getReturnInfo(), FnInfo.getReturnType()));
  assert(CallFnInfo.arg_size() == FnInfo.arg_size());
  for (unsigned i = 0, e = FnInfo.arg_size(); i != e; ++i)
    assert(similar(CallFnInfo.arg_begin()[i].info,
                   CallFnInfo.arg_begin()[i].type,
                   FnInfo.arg_begin()[i].info, FnInfo.arg_begin()[i].type));
#endif
  
  // Determine whether we have a return value slot to use.
  ReturnValueSlot Slot;
  if (!ResultType->isVoidType() &&
      FnInfo.getReturnInfo().getKind() == ABIArgInfo::Indirect &&
      hasAggregateLLVMType(CurFnInfo->getReturnType()))
    Slot = ReturnValueSlot(ReturnValue, ResultType.isVolatileQualified());
  
  // Now emit our call.
  RValue RV = EmitCall(FnInfo, Callee, Slot, CallArgs, MD);
  
  if (!Thunk.Return.isEmpty())
    RV = PerformReturnAdjustment(*this, ResultType, RV, Thunk);

  if (!ResultType->isVoidType() && Slot.isNull())
    CGM.getCXXABI().EmitReturnFromThunk(*this, RV, ResultType);

  // Disable the final ARC autorelease.
  AutoreleaseResult = false;

  FinishFunction();

  // Set the right linkage.
  CGM.setFunctionLinkage(MD, Fn);
  
  // Set the right visibility.
  setThunkVisibility(CGM, MD, Thunk, Fn);
}

void AggExprEmitter::VisitCastExpr(CastExpr *E) {
  if (!DestPtr) {
    Visit(E->getSubExpr());
    return;
  }

  switch (E->getCastKind()) {
  default: assert(0 && "Unhandled cast kind!");

  case CastExpr::CK_ToUnion: {
    // GCC union extension
    QualType PtrTy =
    CGF.getContext().getPointerType(E->getSubExpr()->getType());
    llvm::Value *CastPtr = Builder.CreateBitCast(DestPtr,
                                                 CGF.ConvertType(PtrTy));
    EmitInitializationToLValue(E->getSubExpr(),
                               LValue::MakeAddr(CastPtr, Qualifiers()), 
                               E->getSubExpr()->getType());
    break;
  }

  // FIXME: Remove the CK_Unknown check here.
  case CastExpr::CK_Unknown:
  case CastExpr::CK_NoOp:
  case CastExpr::CK_UserDefinedConversion:
  case CastExpr::CK_ConstructorConversion:
    assert(CGF.getContext().hasSameUnqualifiedType(E->getSubExpr()->getType(),
                                                   E->getType()) &&
           "Implicit cast types must be compatible");
    Visit(E->getSubExpr());
    break;

  case CastExpr::CK_NullToMemberPointer: {
    // If the subexpression's type is the C++0x nullptr_t, emit the
    // subexpression, which may have side effects.
    if (E->getSubExpr()->getType()->isNullPtrType())
      Visit(E->getSubExpr());

    const llvm::Type *PtrDiffTy = 
      CGF.ConvertType(CGF.getContext().getPointerDiffType());

    llvm::Value *NullValue = llvm::Constant::getNullValue(PtrDiffTy);
    llvm::Value *Ptr = Builder.CreateStructGEP(DestPtr, 0, "ptr");
    Builder.CreateStore(NullValue, Ptr, VolatileDest);
    
    llvm::Value *Adj = Builder.CreateStructGEP(DestPtr, 1, "adj");
    Builder.CreateStore(NullValue, Adj, VolatileDest);

    break;
  }
      
  case CastExpr::CK_BitCast: {
    // This must be a member function pointer cast.
    Visit(E->getSubExpr());
    break;
  }

  case CastExpr::CK_DerivedToBaseMemberPointer:
  case CastExpr::CK_BaseToDerivedMemberPointer: {
    QualType SrcType = E->getSubExpr()->getType();
    
    llvm::Value *Src = CGF.CreateMemTemp(SrcType, "tmp");
    CGF.EmitAggExpr(E->getSubExpr(), Src, SrcType.isVolatileQualified());
    
    llvm::Value *SrcPtr = Builder.CreateStructGEP(Src, 0, "src.ptr");
    SrcPtr = Builder.CreateLoad(SrcPtr);
    
    llvm::Value *SrcAdj = Builder.CreateStructGEP(Src, 1, "src.adj");
    SrcAdj = Builder.CreateLoad(SrcAdj);
    
    llvm::Value *DstPtr = Builder.CreateStructGEP(DestPtr, 0, "dst.ptr");
    Builder.CreateStore(SrcPtr, DstPtr, VolatileDest);
    
    llvm::Value *DstAdj = Builder.CreateStructGEP(DestPtr, 1, "dst.adj");
    
    // Now See if we need to update the adjustment.
    const CXXRecordDecl *BaseDecl = 
      cast<CXXRecordDecl>(SrcType->getAs<MemberPointerType>()->
                          getClass()->getAs<RecordType>()->getDecl());
    const CXXRecordDecl *DerivedDecl = 
      cast<CXXRecordDecl>(E->getType()->getAs<MemberPointerType>()->
                          getClass()->getAs<RecordType>()->getDecl());
    if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer)
      std::swap(DerivedDecl, BaseDecl);

    if (llvm::Constant *Adj = 
          CGF.CGM.GetNonVirtualBaseClassOffset(DerivedDecl, BaseDecl)) {
      if (E->getCastKind() == CastExpr::CK_DerivedToBaseMemberPointer)
        SrcAdj = Builder.CreateSub(SrcAdj, Adj, "adj");
      else
        SrcAdj = Builder.CreateAdd(SrcAdj, Adj, "adj");
    }
    
    Builder.CreateStore(SrcAdj, DstAdj, VolatileDest);
    break;
  }
  }
}