//===--- ASTDiagnostic.cpp - Diagnostic Printing Hooks for AST Nodes ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a diagnostic formatting hook for AST elements.
//
//===----------------------------------------------------------------------===//
#include "clang/AST/ASTDiagnostic.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/Type.h"
#include "llvm/Support/raw_ostream.h"
using namespace clang;
// 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, unless it's an alias template.
if (const TemplateSpecializationType *TST
= dyn_cast<TemplateSpecializationType>(Ty))
if (!TST->isTypeAlias())
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()->getTypedefNameForAnonDecl() == 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);
}
/// \brief Convert the given type to a string suitable for printing as part of
/// a diagnostic.
///
/// There are four main criteria when determining whether we should have an
/// a.k.a. clause when pretty-printing a type:
///
/// 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.
/// 4) Two different types within the same diagnostic have the same output
/// string. In this case, force an a.k.a with the desugared type when
/// doing so will provide additional information.
///
/// \param Context the context in which the type was allocated
/// \param Ty the type to print
/// \param QualTypeVals pointer values to QualTypes which are used in the
/// diagnostic message
static std::string
ConvertTypeToDiagnosticString(ASTContext &Context, QualType Ty,
const Diagnostic::ArgumentValue *PrevArgs,
unsigned NumPrevArgs,
llvm::SmallVectorImpl<intptr_t> &QualTypeVals) {
// FIXME: Playing with std::string is really slow.
bool ForceAKA = false;
QualType CanTy = Ty.getCanonicalType();
std::string S = Ty.getAsString(Context.PrintingPolicy);
std::string CanS = CanTy.getAsString(Context.PrintingPolicy);
for (llvm::SmallVectorImpl<intptr_t>::iterator I = QualTypeVals.begin(),
E = QualTypeVals.end(); I != E; ++I) {
QualType CompareTy =
QualType::getFromOpaquePtr(reinterpret_cast<void*>(*I));
if (CompareTy == Ty)
continue; // Same types
QualType CompareCanTy = CompareTy.getCanonicalType();
if (CompareCanTy == CanTy)
continue; // Same canonical types
std::string CompareS = CompareTy.getAsString(Context.PrintingPolicy);
if (CompareS != S)
continue; // Original strings are different
std::string CompareCanS = CompareCanTy.getAsString(Context.PrintingPolicy);
if (CompareCanS == CanS)
continue; // No new info from canonical type
ForceAKA = true;
break;
}
// Check to see if we already desugared this type in this
// diagnostic. If so, don't do it again.
bool Repeated = false;
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 == Ty) {
Repeated = true;
break;
}
}
}
// Consider producing an a.k.a. clause if removing all the direct
// sugar gives us something "significantly different".
if (!Repeated) {
bool ShouldAKA = false;
QualType DesugaredTy = Desugar(Context, Ty, ShouldAKA);
if (ShouldAKA || ForceAKA) {
if (DesugaredTy == Ty) {
DesugaredTy = Ty.getCanonicalType();
}
std::string akaStr = DesugaredTy.getAsString(Context.PrintingPolicy);
if (akaStr != S) {
S = "'" + S + "' (aka '" + akaStr + "')";
return S;
}
}
}
S = "'" + S + "'";
return S;
}
void clang::FormatASTNodeDiagnosticArgument(
Diagnostic::ArgumentKind Kind,
intptr_t Val,
const char *Modifier,
unsigned ModLen,
const char *Argument,
unsigned ArgLen,
const Diagnostic::ArgumentValue *PrevArgs,
unsigned NumPrevArgs,
llvm::SmallVectorImpl<char> &Output,
void *Cookie,
llvm::SmallVectorImpl<intptr_t> &QualTypeVals) {
ASTContext &Context = *static_cast<ASTContext*>(Cookie);
std::string S;
bool NeedQuotes = true;
switch (Kind) {
default: assert(0 && "unknown ArgumentKind");
case Diagnostic::ak_qualtype: {
assert(ModLen == 0 && ArgLen == 0 &&
"Invalid modifier for QualType argument");
QualType Ty(QualType::getFromOpaquePtr(reinterpret_cast<void*>(Val)));
S = ConvertTypeToDiagnosticString(Context, Ty, PrevArgs, NumPrevArgs,
QualTypeVals);
NeedQuotes = false;
break;
}
case Diagnostic::ak_declarationname: {
DeclarationName N = DeclarationName::getFromOpaqueInteger(Val);
S = N.getAsString();
if (ModLen == 9 && !memcmp(Modifier, "objcclass", 9) && ArgLen == 0)
S = '+' + S;
else if (ModLen == 12 && !memcmp(Modifier, "objcinstance", 12)
&& ArgLen==0)
S = '-' + S;
else
assert(ModLen == 0 && ArgLen == 0 &&
"Invalid modifier for DeclarationName argument");
break;
}
case Diagnostic::ak_nameddecl: {
bool Qualified;
if (ModLen == 1 && Modifier[0] == 'q' && ArgLen == 0)
Qualified = true;
else {
assert(ModLen == 0 && ArgLen == 0 &&
"Invalid modifier for NamedDecl* argument");
Qualified = false;
}
reinterpret_cast<NamedDecl*>(Val)->
getNameForDiagnostic(S, Context.PrintingPolicy, Qualified);
break;
}
case Diagnostic::ak_nestednamespec: {
llvm::raw_string_ostream OS(S);
reinterpret_cast<NestedNameSpecifier*>(Val)->print(OS,
Context.PrintingPolicy);
NeedQuotes = false;
break;
}
case Diagnostic::ak_declcontext: {
DeclContext *DC = reinterpret_cast<DeclContext *> (Val);
assert(DC && "Should never have a null declaration context");
if (DC->isTranslationUnit()) {
// FIXME: Get these strings from some localized place
if (Context.getLangOptions().CPlusPlus)
S = "the global namespace";
else
S = "the global scope";
} else if (TypeDecl *Type = dyn_cast<TypeDecl>(DC)) {
S = ConvertTypeToDiagnosticString(Context,
Context.getTypeDeclType(Type),
PrevArgs, NumPrevArgs, QualTypeVals);
} else {
// FIXME: Get these strings from some localized place
NamedDecl *ND = cast<NamedDecl>(DC);
if (isa<NamespaceDecl>(ND))
S += "namespace ";
else if (isa<ObjCMethodDecl>(ND))
S += "method ";
else if (isa<FunctionDecl>(ND))
S += "function ";
S += "'";
ND->getNameForDiagnostic(S, Context.PrintingPolicy, true);
S += "'";
}
NeedQuotes = false;
break;
}
}
if (NeedQuotes)
Output.push_back('\'');
Output.append(S.begin(), S.end());
if (NeedQuotes)
Output.push_back('\'');
}