27#include "llvm/ADT/SmallSet.h"
28#include "llvm/IR/Constants.h"
29#include "llvm/IR/LLVMContext.h"
30#include "llvm/IR/Metadata.h"
31#include "llvm/IR/Module.h"
32#include "llvm/IR/Type.h"
33#include "llvm/Support/Debug.h"
35using namespace CodeGen;
40 : Context(Ctx), CGTypes(CGTypes),
Module(M), CodeGenOpts(CGO),
41 Features(Features), MContext(MContext), MDHelper(M.getContext()),
42 Root(nullptr), Char(nullptr) {}
47llvm::MDNode *CodeGenTBAA::getRoot() {
53 if (Features.CPlusPlus)
54 Root = MDHelper.createTBAARoot(
"Simple C++ TBAA");
56 Root = MDHelper.createTBAARoot(
"Simple C/C++ TBAA");
62llvm::MDNode *CodeGenTBAA::createScalarTypeNode(StringRef Name,
65 if (CodeGenOpts.NewStructPathTBAA) {
66 llvm::Metadata *
Id = MDHelper.createString(Name);
67 return MDHelper.createTBAATypeNode(
Parent, Size,
Id);
69 return MDHelper.createTBAAScalarTypeNode(Name,
Parent);
72llvm::MDNode *CodeGenTBAA::getChar() {
78 Char = createScalarTypeNode(
"omnipotent char", getRoot(), 1);
86 if (TD->hasAttr<MayAliasAttr>())
93 if (TT->getDecl()->hasAttr<MayAliasAttr>())
117llvm::MDNode *CodeGenTBAA::getTypeInfoHelper(
const Type *Ty) {
121 if (
const BuiltinType *BTy = dyn_cast<BuiltinType>(Ty)) {
122 switch (BTy->getKind()) {
128 case BuiltinType::Char_U:
129 case BuiltinType::Char_S:
130 case BuiltinType::UChar:
131 case BuiltinType::SChar:
135 case BuiltinType::UShort:
137 case BuiltinType::UInt:
139 case BuiltinType::ULong:
141 case BuiltinType::ULongLong:
143 case BuiltinType::UInt128:
146 case BuiltinType::UShortFract:
148 case BuiltinType::UFract:
150 case BuiltinType::ULongFract:
153 case BuiltinType::SatUShortFract:
155 case BuiltinType::SatUFract:
157 case BuiltinType::SatULongFract:
160 case BuiltinType::UShortAccum:
162 case BuiltinType::UAccum:
164 case BuiltinType::ULongAccum:
167 case BuiltinType::SatUShortAccum:
169 case BuiltinType::SatUAccum:
171 case BuiltinType::SatULongAccum:
178 return createScalarTypeNode(BTy->getName(Features), getChar(), Size);
213 llvm::MDNode *AnyPtr = createScalarTypeNode(
"any pointer", getChar(), Size);
214 if (!CodeGenOpts.PointerTBAA)
218 unsigned PtrDepth = 0;
225 if (isa<BuiltinType>(Ty)) {
226 llvm::MDNode *ScalarMD = getTypeInfoHelper(Ty);
228 cast<llvm::MDString>(
229 ScalarMD->getOperand(CodeGenOpts.NewStructPathTBAA ? 2 : 0))
232 OutName += std::to_string(PtrDepth);
235 return createScalarTypeNode(OutName, AnyPtr, Size);
241 if (CodeGenOpts.NewStructPathTBAA && Ty->
isArrayType())
242 return getTypeInfo(cast<ArrayType>(Ty)->getElementType());
246 if (
const EnumType *ETy = dyn_cast<EnumType>(Ty)) {
247 if (!Features.CPlusPlus)
248 return getTypeInfo(ETy->getDecl()->getIntegerType());
254 if (!ETy->getDecl()->isExternallyVisible())
258 llvm::raw_svector_ostream Out(OutName);
260 return createScalarTypeNode(OutName, getChar(), Size);
263 if (
const auto *EIT = dyn_cast<BitIntType>(Ty)) {
265 llvm::raw_svector_ostream Out(OutName);
268 Out <<
"_BitInt(" << EIT->getNumBits() <<
')';
269 return createScalarTypeNode(OutName, getChar(), Size);
278 if (CodeGenOpts.OptimizationLevel == 0 || CodeGenOpts.RelaxedAliasing)
294 return getValidBaseTypeInfo(QTy);
297 if (llvm::MDNode *N = MetadataCache[Ty])
303 llvm::MDNode *TypeNode = getTypeInfoHelper(Ty);
304 return MetadataCache[Ty] = TypeNode;
321 const llvm::DataLayout &DL =
Module.getDataLayout();
322 unsigned Size = DL.getPointerTypeSize(VTablePtrType);
323 return TBAAAccessInfo(createScalarTypeNode(
"vtable pointer", getRoot(), Size),
328CodeGenTBAA::CollectFields(uint64_t BaseOffset,
336 if (TTy->isUnionType()) {
338 llvm::MDNode *TBAAType = getChar();
341 llvm::MDBuilder::TBAAStructField(BaseOffset, Size, TBAATag));
350 if (
Decl->bases_begin() !=
Decl->bases_end())
358 i != e; ++i, ++idx) {
367 if ((*i)->isBitField()) {
379 llvm::divideCeil(CurrentBitFieldSize, Context.
getCharWidth());
380 llvm::MDNode *TBAAType = getChar();
381 llvm::MDNode *TBAATag =
384 llvm::MDBuilder::TBAAStructField(Offset, Size, TBAATag));
389 if (!CollectFields(Offset, FieldQTy, Fields,
401 Fields.push_back(llvm::MDBuilder::TBAAStructField(Offset, Size, TBAATag));
407 if (CodeGenOpts.OptimizationLevel == 0 || CodeGenOpts.RelaxedAliasing)
412 if (llvm::MDNode *N = StructMetadataCache[Ty])
417 return MDHelper.createTBAAStructNode(Fields);
420 return StructMetadataCache[Ty] =
nullptr;
423llvm::MDNode *CodeGenTBAA::getBaseTypeInfoHelper(
const Type *Ty) {
424 if (
auto *TTy = dyn_cast<RecordType>(Ty)) {
427 using TBAAStructField = llvm::MDBuilder::TBAAStructField;
429 if (
const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
433 if (CodeGenOpts.NewStructPathTBAA && CXXRD->getNumVBases() != 0)
443 ? getValidBaseTypeInfo(BaseQTy)
451 llvm::MDBuilder::TBAAStructField(Offset, Size, TypeNode));
459 [](
const TBAAStructField &A,
const TBAAStructField &B) {
460 return A.Offset < B.Offset;
464 if (
Field->isZeroSize(Context) ||
Field->isUnnamedBitField())
468 ? getValidBaseTypeInfo(FieldQTy)
476 Fields.push_back(llvm::MDBuilder::TBAAStructField(Offset, Size,
481 if (Features.CPlusPlus) {
483 llvm::raw_svector_ostream Out(OutName);
489 if (CodeGenOpts.NewStructPathTBAA) {
490 llvm::MDNode *
Parent = getChar();
492 llvm::Metadata *
Id = MDHelper.createString(OutName);
493 return MDHelper.createTBAATypeNode(
Parent, Size,
Id, Fields);
498 for (
const auto &Field : Fields)
499 OffsetsAndTypes.push_back(std::make_pair(
Field.Type,
Field.Offset));
500 return MDHelper.createTBAAStructTypeNode(OutName, OffsetsAndTypes);
506llvm::MDNode *CodeGenTBAA::getValidBaseTypeInfo(
QualType QTy) {
512 auto I = BaseTypeMetadataCache.find(Ty);
513 if (I != BaseTypeMetadataCache.end())
518 llvm::MDNode *TypeNode = getBaseTypeInfoHelper(Ty);
519 LLVM_ATTRIBUTE_UNUSED
auto inserted =
520 BaseTypeMetadataCache.insert({Ty, TypeNode});
521 assert(inserted.second &&
"BaseType metadata was already inserted");
531 assert(!Info.
isIncomplete() &&
"Access to an object of an incomplete type!");
539 if (!CodeGenOpts.StructPathTBAA)
542 llvm::MDNode *&N = AccessTagMetadataCache[Info];
548 assert(!Info.
Offset &&
"Nonzero offset for an access with no base type!");
550 if (CodeGenOpts.NewStructPathTBAA) {
571 if (!InfoA || !InfoB)
586 if (DestInfo == SrcInfo)
589 if (!DestInfo || !SrcInfo)
Defines the clang::ASTContext interface.
static bool TypeHasMayAlias(QualType QTy)
static bool isValidBaseType(QualType QTy)
Check if the given type is a valid base type to be used in access tags.
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
const ASTRecordLayout & getASTRecordLayout(const RecordDecl *D) const
Get or compute information about the layout of the specified record (struct/union/class) D,...
CanQualType getCanonicalType(QualType T) const
Return the canonical (structural) type corresponding to the specified potentially non-canonical type ...
CanQualType SatLongAccumTy
CanQualType SatShortFractTy
CharUnits getTypeSizeInChars(QualType T) const
Return the size of the specified (complete) type T, in characters.
CanQualType SatLongFractTy
const TargetInfo & getTargetInfo() const
CanQualType SatShortAccumTy
CharUnits toCharUnitsFromBits(int64_t BitSize) const
Convert a size in bits to a size in characters.
uint64_t getCharWidth() const
Return the size of the character type, in bits.
ASTRecordLayout - This class contains layout information for one RecordDecl, which is a struct/union/...
uint64_t getFieldOffset(unsigned FieldNo) const
getFieldOffset - Get the offset of the given field index, in bits.
CharUnits getDataSize() const
getDataSize() - Get the record data size, which is the record size without tail padding,...
CharUnits getBaseClassOffset(const CXXRecordDecl *Base) const
getBaseClassOffset - Get the offset, in chars, for the given base class.
This class is used for builtin types like 'int'.
Represents a base class of a C++ class.
Represents a C++ struct/union/class.
bool isEmpty() const
Determine whether this is an empty class in the sense of (C++11 [meta.unary.prop]).
const T * getTypePtr() const
Retrieve the underlying type pointer, which refers to a canonical type.
QuantityType getQuantity() const
getQuantity - Get the raw integer representation of this quantity.
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
CGRecordLayout - This class handles struct and union layout info while lowering AST types to LLVM typ...
const CGBitFieldInfo & getBitFieldInfo(const FieldDecl *FD) const
Return the BitFieldInfo that corresponds to the field FD.
llvm::MDNode * getBaseTypeInfo(QualType QTy)
getBaseTypeInfo - Get metadata that describes the given base access type.
llvm::MDNode * getTypeInfo(QualType QTy)
getTypeInfo - Get metadata used to describe accesses to objects of the given type.
TBAAAccessInfo getVTablePtrAccessInfo(llvm::Type *VTablePtrType)
getVTablePtrAccessInfo - Get the TBAA information that describes an access to a virtual table pointer...
TBAAAccessInfo mergeTBAAInfoForMemoryTransfer(TBAAAccessInfo DestInfo, TBAAAccessInfo SrcInfo)
mergeTBAAInfoForMemoryTransfer - Get merged TBAA information for the purpose of memory transfer calls...
TBAAAccessInfo mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo, TBAAAccessInfo TargetInfo)
mergeTBAAInfoForCast - Get merged TBAA information for the purpose of type casts.
TBAAAccessInfo mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA, TBAAAccessInfo InfoB)
mergeTBAAInfoForConditionalOperator - Get merged TBAA information for the purpose of conditional oper...
llvm::MDNode * getAccessTagInfo(TBAAAccessInfo Info)
getAccessTagInfo - Get TBAA tag for a given memory access.
llvm::MDNode * getTBAAStructInfo(QualType QTy)
getTBAAStructInfo - Get the TBAAStruct MDNode to be used for a memcpy of the given type.
CodeGenTBAA(ASTContext &Ctx, CodeGenTypes &CGTypes, llvm::Module &M, const CodeGenOptions &CGO, const LangOptions &Features, MangleContext &MContext)
TBAAAccessInfo getAccessInfo(QualType AccessType)
getAccessInfo - Get TBAA information that describes an access to an object of the given type.
This class organizes the cross-module state that is used while lowering AST types to LLVM types.
const CGRecordLayout & getCGRecordLayout(const RecordDecl *)
getCGRecordLayout - Return record layout info for the given record decl.
specific_decl_iterator - Iterates over a subrange of declarations stored in a DeclContext,...
Decl - This represents one declaration (or definition), e.g.
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of enums.
Represents a member of a struct/union/class.
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
MangleContext - Context for tracking state which persists across multiple calls to the C++ name mangl...
virtual void mangleCanonicalTypeName(QualType T, raw_ostream &, bool NormalizeIntegers=false)=0
Generates a unique string for an externally visible type for use with TBAA or type uniquing.
Describes a module or submodule.
StringRef getName() const
Get the name of identifier for this declaration as a StringRef.
A (possibly-)qualified type.
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Represents a struct/union/class.
bool hasFlexibleArrayMember() const
field_iterator field_end() const
field_range fields() const
RecordDecl * getDefinition() const
Returns the RecordDecl that actually defines this struct/union/class.
field_iterator field_begin() const
A helper class that allows the use of isa/cast/dyncast to detect TagType objects of structs/unions/cl...
Exposes information about the current target.
The base class of the type hierarchy.
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
bool isPointerType() const
bool isReferenceType() const
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee.
bool isStdByteType() const
bool isIncompleteType(NamedDecl **Def=nullptr) const
Types are partitioned into 3 broad categories (C99 6.2.5p1): object types, function types,...
const T * getAs() const
Member-template getAs<specific type>'.
TagDecl * getAsTagDecl() const
Retrieves the TagDecl that this type refers to, either because the type is a TagType or because it is...
Defines the clang::TargetInfo interface.
bool isEmptyFieldForLayout(const ASTContext &Context, const FieldDecl *FD)
isEmptyFieldForLayout - Return true iff the field is "empty", that is, either a zero-width bit-field ...
The JSON file list parser is used to communicate input to InstallAPI.
if(T->getSizeExpr()) TRY_TO(TraverseStmt(const_cast< Expr * >(T -> getSizeExpr())))
Structure with information about how a bitfield should be accessed.
unsigned Offset
The offset within a contiguous run of bitfields that are represented as a single "field" within the L...
unsigned Size
The total size of the bit-field, in bits.
unsigned StorageSize
The storage size in bits which should be used when accessing this bitfield.
llvm::MDNode * AccessType
AccessType - The final access type.
uint64_t Offset
Offset - The byte offset of the final access within the base one.
static TBAAAccessInfo getMayAliasInfo()
uint64_t Size
Size - The size of access, in bytes.
static TBAAAccessInfo getIncompleteInfo()
llvm::MDNode * BaseType
BaseType - The base/leading access type.
bool isIncomplete() const