/// DecodeTypeFromStr - This decodes one type descriptor from Str, advancing the
/// pointer over the consumed characters. This returns the resultant type.
static QualType DecodeTypeFromStr(const char *&Str, ASTContext &Context,
Builtin::Context::GetBuiltinTypeError &Error,
bool AllowTypeModifiers = true) {
// Modifiers.
int HowLong = 0;
bool Signed = false, Unsigned = false;
// Read the modifiers first.
bool Done = false;
while (!Done) {
switch (*Str++) {
default: Done = true; --Str; break;
case 'S':
assert(!Unsigned && "Can't use both 'S' and 'U' modifiers!");
assert(!Signed && "Can't use 'S' modifier multiple times!");
Signed = true;
break;
case 'U':
assert(!Signed && "Can't use both 'S' and 'U' modifiers!");
assert(!Unsigned && "Can't use 'S' modifier multiple times!");
Unsigned = true;
break;
case 'L':
assert(HowLong <= 2 && "Can't have LLLL modifier");
++HowLong;
break;
}
}
QualType Type;
// Read the base type.
switch (*Str++) {
default: assert(0 && "Unknown builtin type letter!");
case 'v':
assert(HowLong == 0 && !Signed && !Unsigned &&
"Bad modifiers used with 'v'!");
Type = Context.VoidTy;
break;
case 'f':
assert(HowLong == 0 && !Signed && !Unsigned &&
"Bad modifiers used with 'f'!");
Type = Context.FloatTy;
break;
case 'd':
assert(HowLong < 2 && !Signed && !Unsigned &&
"Bad modifiers used with 'd'!");
if (HowLong)
Type = Context.LongDoubleTy;
else
Type = Context.DoubleTy;
break;
case 's':
assert(HowLong == 0 && "Bad modifiers used with 's'!");
if (Unsigned)
Type = Context.UnsignedShortTy;
else
Type = Context.ShortTy;
break;
case 'i':
if (HowLong == 3)
Type = Unsigned ? Context.UnsignedInt128Ty : Context.Int128Ty;
else if (HowLong == 2)
Type = Unsigned ? Context.UnsignedLongLongTy : Context.LongLongTy;
else if (HowLong == 1)
Type = Unsigned ? Context.UnsignedLongTy : Context.LongTy;
else
Type = Unsigned ? Context.UnsignedIntTy : Context.IntTy;
break;
case 'c':
assert(HowLong == 0 && "Bad modifiers used with 'c'!");
if (Signed)
Type = Context.SignedCharTy;
else if (Unsigned)
Type = Context.UnsignedCharTy;
else
Type = Context.CharTy;
break;
case 'b': // boolean
assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'b'!");
Type = Context.BoolTy;
break;
case 'z': // size_t.
assert(HowLong == 0 && !Signed && !Unsigned && "Bad modifiers for 'z'!");
Type = Context.getSizeType();
break;
case 'F':
Type = Context.getCFConstantStringType();
break;
case 'a':
Type = Context.getBuiltinVaListType();
assert(!Type.isNull() && "builtin va list type not initialized!");
break;
case 'A':
// This is a "reference" to a va_list; however, what exactly
// this means depends on how va_list is defined. There are two
// different kinds of va_list: ones passed by value, and ones
// passed by reference. An example of a by-value va_list is
// x86, where va_list is a char*. An example of by-ref va_list
// is x86-64, where va_list is a __va_list_tag[1]. For x86,
// we want this argument to be a char*&; for x86-64, we want
// it to be a __va_list_tag*.
Type = Context.getBuiltinVaListType();
assert(!Type.isNull() && "builtin va list type not initialized!");
if (Type->isArrayType()) {
Type = Context.getArrayDecayedType(Type);
} else {
Type = Context.getLValueReferenceType(Type);
}
break;
case 'V': {
char *End;
unsigned NumElements = strtoul(Str, &End, 10);
assert(End != Str && "Missing vector size");
Str = End;
QualType ElementType = DecodeTypeFromStr(Str, Context, Error, false);
Type = Context.getVectorType(ElementType, NumElements);
break;
}
case 'P': {
IdentifierInfo *II = &Context.Idents.get("FILE");
DeclContext::lookup_result Lookup
= Context.getTranslationUnitDecl()->lookup(Context, II);
if (Lookup.first != Lookup.second && isa<TypeDecl>(*Lookup.first)) {
Type = Context.getTypeDeclType(cast<TypeDecl>(*Lookup.first));
break;
}
else {
Error = Builtin::Context::GE_Missing_FILE;
return QualType();
}
}
}
if (!AllowTypeModifiers)
return Type;
Done = false;
while (!Done) {
switch (*Str++) {
default: Done = true; --Str; break;
case '*':
Type = Context.getPointerType(Type);
break;
case '&':
Type = Context.getLValueReferenceType(Type);
break;
// FIXME: There's no way to have a built-in with an rvalue ref arg.
case 'C':
Type = Type.getQualifiedType(QualType::Const);
break;
}
}
return Type;
}
// Returns a desugared version of the QualType, and marks ShouldAKA as true
// whenever we remove significant sugar from the type.
static QualType Desugar(ASTContext &Context, QualType QT, bool &ShouldAKA) {
QualifierCollector QC;
while (true) {
const Type *Ty = QC.strip(QT);
// Don't aka just because we saw an elaborated type...
if (const ElaboratedType *ET = dyn_cast<ElaboratedType>(Ty)) {
QT = ET->desugar();
continue;
}
// ... or a paren type ...
if (const ParenType *PT = dyn_cast<ParenType>(Ty)) {
QT = PT->desugar();
continue;
}
// ...or a substituted template type parameter ...
if (const SubstTemplateTypeParmType *ST =
dyn_cast<SubstTemplateTypeParmType>(Ty)) {
QT = ST->desugar();
continue;
}
// ...or an attributed type...
if (const AttributedType *AT = dyn_cast<AttributedType>(Ty)) {
QT = AT->desugar();
continue;
}
// ... or an auto type.
if (const AutoType *AT = dyn_cast<AutoType>(Ty)) {
if (!AT->isSugared())
break;
QT = AT->desugar();
continue;
}
// Don't desugar template specializations.
if (isa<TemplateSpecializationType>(Ty))
break;
// Don't desugar magic Objective-C types.
if (QualType(Ty,0) == Context.getObjCIdType() ||
QualType(Ty,0) == Context.getObjCClassType() ||
QualType(Ty,0) == Context.getObjCSelType() ||
QualType(Ty,0) == Context.getObjCProtoType())
break;
// Don't desugar va_list.
if (QualType(Ty,0) == Context.getBuiltinVaListType())
break;
// Otherwise, do a single-step desugar.
QualType Underlying;
bool IsSugar = false;
switch (Ty->getTypeClass()) {
#define ABSTRACT_TYPE(Class, Base)
#define TYPE(Class, Base) \
case Type::Class: { \
const Class##Type *CTy = cast<Class##Type>(Ty); \
if (CTy->isSugared()) { \
IsSugar = true; \
Underlying = CTy->desugar(); \
} \
break; \
}
#include "clang/AST/TypeNodes.def"
}
// If it wasn't sugared, we're done.
if (!IsSugar)
break;
// If the desugared type is a vector type, we don't want to expand
// it, it will turn into an attribute mess. People want their "vec4".
if (isa<VectorType>(Underlying))
break;
// Don't desugar through the primary typedef of an anonymous type.
if (const TagType *UTT = Underlying->getAs<TagType>())
if (const TypedefType *QTT = dyn_cast<TypedefType>(QT))
if (UTT->getDecl()->getTypedefForAnonDecl() == QTT->getDecl())
break;
// Record that we actually looked through an opaque type here.
ShouldAKA = true;
QT = Underlying;
}
// If we have a pointer-like type, desugar the pointee as well.
// FIXME: Handle other pointer-like types.
if (const PointerType *Ty = QT->getAs<PointerType>()) {
QT = Context.getPointerType(Desugar(Context, Ty->getPointeeType(),
ShouldAKA));
} else if (const LValueReferenceType *Ty = QT->getAs<LValueReferenceType>()) {
QT = Context.getLValueReferenceType(Desugar(Context, Ty->getPointeeType(),
ShouldAKA));
} else if (const RValueReferenceType *Ty = QT->getAs<RValueReferenceType>()) {
QT = Context.getRValueReferenceType(Desugar(Context, Ty->getPointeeType(),
ShouldAKA));
}
return QC.apply(Context, QT);
}
/// Determines whether we should have an a.k.a. clause when
/// pretty-printing a type. There are three main criteria:
///
/// 1) Some types provide very minimal sugar that doesn't impede the
/// user's understanding --- for example, elaborated type
/// specifiers. If this is all the sugar we see, we don't want an
/// a.k.a. clause.
/// 2) Some types are technically sugared but are much more familiar
/// when seen in their sugared form --- for example, va_list,
/// vector types, and the magic Objective C types. We don't
/// want to desugar these, even if we do produce an a.k.a. clause.
/// 3) Some types may have already been desugared previously in this diagnostic.
/// if this is the case, doing another "aka" would just be clutter.
///
static bool ShouldAKA(ASTContext &Context, QualType QT,
const Diagnostic::ArgumentValue *PrevArgs,
unsigned NumPrevArgs,
QualType &DesugaredQT) {
QualType InputTy = QT;
bool AKA = false;
QualifierCollector Qc;
while (true) {
const Type *Ty = Qc.strip(QT);
// Don't aka just because we saw an elaborated type...
if (isa<ElaboratedType>(Ty)) {
QT = cast<ElaboratedType>(Ty)->desugar();
continue;
}
// ...or a qualified name type...
if (isa<QualifiedNameType>(Ty)) {
QT = cast<QualifiedNameType>(Ty)->desugar();
continue;
}
// ...or an injected class name...
if (isa<InjectedClassNameType>(Ty)) {
QT = cast<InjectedClassNameType>(Ty)->desugar();
continue;
}
// ...or a substituted template type parameter.
if (isa<SubstTemplateTypeParmType>(Ty)) {
QT = cast<SubstTemplateTypeParmType>(Ty)->desugar();
continue;
}
// Don't desugar template specializations.
if (isa<TemplateSpecializationType>(Ty))
break;
// Don't desugar magic Objective-C types.
if (QualType(Ty,0) == Context.getObjCIdType() ||
QualType(Ty,0) == Context.getObjCClassType() ||
QualType(Ty,0) == Context.getObjCSelType() ||
QualType(Ty,0) == Context.getObjCProtoType())
break;
// Don't desugar va_list.
if (QualType(Ty,0) == Context.getBuiltinVaListType())
break;
// Otherwise, do a single-step desugar.
QualType Underlying;
bool IsSugar = false;
switch (Ty->getTypeClass()) {
#define ABSTRACT_TYPE(Class, Base)
#define TYPE(Class, Base) \
case Type::Class: { \
const Class##Type *CTy = cast<Class##Type>(Ty); \
if (CTy->isSugared()) { \
IsSugar = true; \
Underlying = CTy->desugar(); \
} \
break; \
}
#include "clang/AST/TypeNodes.def"
}
// If it wasn't sugared, we're done.
if (!IsSugar)
break;
// If the desugared type is a vector type, we don't want to expand
// it, it will turn into an attribute mess. People want their "vec4".
if (isa<VectorType>(Underlying))
break;
// Don't desugar through the primary typedef of an anonymous type.
if (isa<TagType>(Underlying) && isa<TypedefType>(QT))
if (cast<TagType>(Underlying)->getDecl()->getTypedefForAnonDecl() ==
cast<TypedefType>(QT)->getDecl())
break;
// Otherwise, we're tearing through something opaque; note that
// we'll eventually need an a.k.a. clause and keep going.
AKA = true;
QT = Underlying;
continue;
}
// If we never tore through opaque sugar, don't print aka.
if (!AKA) return false;
// If we did, check to see if we already desugared this type in this
// diagnostic. If so, don't do it again.
for (unsigned i = 0; i != NumPrevArgs; ++i) {
// TODO: Handle ak_declcontext case.
if (PrevArgs[i].first == Diagnostic::ak_qualtype) {
void *Ptr = (void*)PrevArgs[i].second;
QualType PrevTy(QualType::getFromOpaquePtr(Ptr));
if (PrevTy == InputTy)
return false;
}
}
DesugaredQT = Qc.apply(QT);
return true;
}
