1 //===- TypeLoc.cpp - Type Source Info Wrapper -----------------------------===//
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 TypeLoc subclasses implementations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/TypeLoc.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Expr.h"
17 #include "clang/AST/NestedNameSpecifier.h"
18 #include "clang/AST/TemplateBase.h"
19 #include "clang/AST/TemplateName.h"
20 #include "clang/AST/TypeLocVisitor.h"
21 #include "clang/Basic/SourceLocation.h"
22 #include "clang/Basic/Specifiers.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/MathExtras.h"
25 #include <algorithm>
26 #include <cassert>
27 #include <cstdint>
28 #include <cstring>
29 
30 using namespace clang;
31 
32 static const unsigned TypeLocMaxDataAlign = alignof(void *);
33 
34 //===----------------------------------------------------------------------===//
35 // TypeLoc Implementation
36 //===----------------------------------------------------------------------===//
37 
38 namespace {
39 
40 class TypeLocRanger : public TypeLocVisitor<TypeLocRanger, SourceRange> {
41 public:
42 #define ABSTRACT_TYPELOC(CLASS, PARENT)
43 #define TYPELOC(CLASS, PARENT) \
44   SourceRange Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc) { \
45     return TyLoc.getLocalSourceRange(); \
46   }
47 #include "clang/AST/TypeLocNodes.def"
48 };
49 
50 } // namespace
51 
52 SourceRange TypeLoc::getLocalSourceRangeImpl(TypeLoc TL) {
53   if (TL.isNull()) return SourceRange();
54   return TypeLocRanger().Visit(TL);
55 }
56 
57 namespace {
58 
59 class TypeAligner : public TypeLocVisitor<TypeAligner, unsigned> {
60 public:
61 #define ABSTRACT_TYPELOC(CLASS, PARENT)
62 #define TYPELOC(CLASS, PARENT) \
63   unsigned Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc) { \
64     return TyLoc.getLocalDataAlignment(); \
65   }
66 #include "clang/AST/TypeLocNodes.def"
67 };
68 
69 } // namespace
70 
71 /// \brief Returns the alignment of the type source info data block.
72 unsigned TypeLoc::getLocalAlignmentForType(QualType Ty) {
73   if (Ty.isNull()) return 1;
74   return TypeAligner().Visit(TypeLoc(Ty, nullptr));
75 }
76 
77 namespace {
78 
79 class TypeSizer : public TypeLocVisitor<TypeSizer, unsigned> {
80 public:
81 #define ABSTRACT_TYPELOC(CLASS, PARENT)
82 #define TYPELOC(CLASS, PARENT) \
83   unsigned Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc) { \
84     return TyLoc.getLocalDataSize(); \
85   }
86 #include "clang/AST/TypeLocNodes.def"
87 };
88 
89 } // namespace
90 
91 /// \brief Returns the size of the type source info data block.
92 unsigned TypeLoc::getFullDataSizeForType(QualType Ty) {
93   unsigned Total = 0;
94   TypeLoc TyLoc(Ty, nullptr);
95   unsigned MaxAlign = 1;
96   while (!TyLoc.isNull()) {
97     unsigned Align = getLocalAlignmentForType(TyLoc.getType());
98     MaxAlign = std::max(Align, MaxAlign);
99     Total = llvm::alignTo(Total, Align);
100     Total += TypeSizer().Visit(TyLoc);
101     TyLoc = TyLoc.getNextTypeLoc();
102   }
103   Total = llvm::alignTo(Total, MaxAlign);
104   return Total;
105 }
106 
107 namespace {
108 
109 class NextLoc : public TypeLocVisitor<NextLoc, TypeLoc> {
110 public:
111 #define ABSTRACT_TYPELOC(CLASS, PARENT)
112 #define TYPELOC(CLASS, PARENT) \
113   TypeLoc Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc) { \
114     return TyLoc.getNextTypeLoc(); \
115   }
116 #include "clang/AST/TypeLocNodes.def"
117 };
118 
119 } // namespace
120 
121 /// \brief Get the next TypeLoc pointed by this TypeLoc, e.g for "int*" the
122 /// TypeLoc is a PointerLoc and next TypeLoc is for "int".
123 TypeLoc TypeLoc::getNextTypeLocImpl(TypeLoc TL) {
124   return NextLoc().Visit(TL);
125 }
126 
127 /// \brief Initializes a type location, and all of its children
128 /// recursively, as if the entire tree had been written in the
129 /// given location.
130 void TypeLoc::initializeImpl(ASTContext &Context, TypeLoc TL,
131                              SourceLocation Loc) {
132   while (true) {
133     switch (TL.getTypeLocClass()) {
134 #define ABSTRACT_TYPELOC(CLASS, PARENT)
135 #define TYPELOC(CLASS, PARENT)        \
136     case CLASS: {                     \
137       CLASS##TypeLoc TLCasted = TL.castAs<CLASS##TypeLoc>(); \
138       TLCasted.initializeLocal(Context, Loc);  \
139       TL = TLCasted.getNextTypeLoc(); \
140       if (!TL) return;                \
141       continue;                       \
142     }
143 #include "clang/AST/TypeLocNodes.def"
144     }
145   }
146 }
147 
148 namespace {
149 
150 class TypeLocCopier : public TypeLocVisitor<TypeLocCopier> {
151   TypeLoc Source;
152 
153 public:
154   TypeLocCopier(TypeLoc source) : Source(source) {}
155 
156 #define ABSTRACT_TYPELOC(CLASS, PARENT)
157 #define TYPELOC(CLASS, PARENT)                          \
158   void Visit##CLASS##TypeLoc(CLASS##TypeLoc dest) {   \
159     dest.copyLocal(Source.castAs<CLASS##TypeLoc>());  \
160   }
161 #include "clang/AST/TypeLocNodes.def"
162 };
163 
164 } // namespace
165 
166 void TypeLoc::copy(TypeLoc other) {
167   assert(getFullDataSize() == other.getFullDataSize());
168 
169   // If both data pointers are aligned to the maximum alignment, we
170   // can memcpy because getFullDataSize() accurately reflects the
171   // layout of the data.
172   if (reinterpret_cast<uintptr_t>(Data) ==
173           llvm::alignTo(reinterpret_cast<uintptr_t>(Data),
174                         TypeLocMaxDataAlign) &&
175       reinterpret_cast<uintptr_t>(other.Data) ==
176           llvm::alignTo(reinterpret_cast<uintptr_t>(other.Data),
177                         TypeLocMaxDataAlign)) {
178     memcpy(Data, other.Data, getFullDataSize());
179     return;
180   }
181 
182   // Copy each of the pieces.
183   TypeLoc TL(getType(), Data);
184   do {
185     TypeLocCopier(other).Visit(TL);
186     other = other.getNextTypeLoc();
187   } while ((TL = TL.getNextTypeLoc()));
188 }
189 
190 SourceLocation TypeLoc::getBeginLoc() const {
191   TypeLoc Cur = *this;
192   TypeLoc LeftMost = Cur;
193   while (true) {
194     switch (Cur.getTypeLocClass()) {
195     case Elaborated:
196       LeftMost = Cur;
197       break;
198     case FunctionProto:
199       if (Cur.castAs<FunctionProtoTypeLoc>().getTypePtr()
200               ->hasTrailingReturn()) {
201         LeftMost = Cur;
202         break;
203       }
204       LLVM_FALLTHROUGH;
205     case FunctionNoProto:
206     case ConstantArray:
207     case DependentSizedArray:
208     case IncompleteArray:
209     case VariableArray:
210       // FIXME: Currently QualifiedTypeLoc does not have a source range
211     case Qualified:
212       Cur = Cur.getNextTypeLoc();
213       continue;
214     default:
215       if (Cur.getLocalSourceRange().getBegin().isValid())
216         LeftMost = Cur;
217       Cur = Cur.getNextTypeLoc();
218       if (Cur.isNull())
219         break;
220       continue;
221     } // switch
222     break;
223   } // while
224   return LeftMost.getLocalSourceRange().getBegin();
225 }
226 
227 SourceLocation TypeLoc::getEndLoc() const {
228   TypeLoc Cur = *this;
229   TypeLoc Last;
230   while (true) {
231     switch (Cur.getTypeLocClass()) {
232     default:
233       if (!Last)
234         Last = Cur;
235       return Last.getLocalSourceRange().getEnd();
236     case Paren:
237     case ConstantArray:
238     case DependentSizedArray:
239     case IncompleteArray:
240     case VariableArray:
241     case FunctionNoProto:
242       Last = Cur;
243       break;
244     case FunctionProto:
245       if (Cur.castAs<FunctionProtoTypeLoc>().getTypePtr()->hasTrailingReturn())
246         Last = TypeLoc();
247       else
248         Last = Cur;
249       break;
250     case Pointer:
251     case BlockPointer:
252     case MemberPointer:
253     case LValueReference:
254     case RValueReference:
255     case PackExpansion:
256       if (!Last)
257 	Last = Cur;
258       break;
259     case Qualified:
260     case Elaborated:
261       break;
262     }
263     Cur = Cur.getNextTypeLoc();
264   }
265 }
266 
267 namespace {
268 
269 struct TSTChecker : public TypeLocVisitor<TSTChecker, bool> {
270   // Overload resolution does the real work for us.
271   static bool isTypeSpec(TypeSpecTypeLoc _) { return true; }
272   static bool isTypeSpec(TypeLoc _) { return false; }
273 
274 #define ABSTRACT_TYPELOC(CLASS, PARENT)
275 #define TYPELOC(CLASS, PARENT) \
276   bool Visit##CLASS##TypeLoc(CLASS##TypeLoc TyLoc) { \
277     return isTypeSpec(TyLoc); \
278   }
279 #include "clang/AST/TypeLocNodes.def"
280 };
281 
282 } // namespace
283 
284 /// \brief Determines if the given type loc corresponds to a
285 /// TypeSpecTypeLoc.  Since there is not actually a TypeSpecType in
286 /// the type hierarchy, this is made somewhat complicated.
287 ///
288 /// There are a lot of types that currently use TypeSpecTypeLoc
289 /// because it's a convenient base class.  Ideally we would not accept
290 /// those here, but ideally we would have better implementations for
291 /// them.
292 bool TypeSpecTypeLoc::isKind(const TypeLoc &TL) {
293   if (TL.getType().hasLocalQualifiers()) return false;
294   return TSTChecker().Visit(TL);
295 }
296 
297 // Reimplemented to account for GNU/C++ extension
298 //     typeof unary-expression
299 // where there are no parentheses.
300 SourceRange TypeOfExprTypeLoc::getLocalSourceRange() const {
301   if (getRParenLoc().isValid())
302     return SourceRange(getTypeofLoc(), getRParenLoc());
303   else
304     return SourceRange(getTypeofLoc(),
305                        getUnderlyingExpr()->getSourceRange().getEnd());
306 }
307 
308 
309 TypeSpecifierType BuiltinTypeLoc::getWrittenTypeSpec() const {
310   if (needsExtraLocalData())
311     return static_cast<TypeSpecifierType>(getWrittenBuiltinSpecs().Type);
312   switch (getTypePtr()->getKind()) {
313   case BuiltinType::Void:
314     return TST_void;
315   case BuiltinType::Bool:
316     return TST_bool;
317   case BuiltinType::Char_U:
318   case BuiltinType::Char_S:
319     return TST_char;
320   case BuiltinType::Char16:
321     return TST_char16;
322   case BuiltinType::Char32:
323     return TST_char32;
324   case BuiltinType::WChar_S:
325   case BuiltinType::WChar_U:
326     return TST_wchar;
327   case BuiltinType::UChar:
328   case BuiltinType::UShort:
329   case BuiltinType::UInt:
330   case BuiltinType::ULong:
331   case BuiltinType::ULongLong:
332   case BuiltinType::UInt128:
333   case BuiltinType::SChar:
334   case BuiltinType::Short:
335   case BuiltinType::Int:
336   case BuiltinType::Long:
337   case BuiltinType::LongLong:
338   case BuiltinType::Int128:
339   case BuiltinType::Half:
340   case BuiltinType::Float:
341   case BuiltinType::Double:
342   case BuiltinType::LongDouble:
343   case BuiltinType::Float16:
344   case BuiltinType::Float128:
345     llvm_unreachable("Builtin type needs extra local data!");
346     // Fall through, if the impossible happens.
347 
348   case BuiltinType::NullPtr:
349   case BuiltinType::Overload:
350   case BuiltinType::Dependent:
351   case BuiltinType::BoundMember:
352   case BuiltinType::UnknownAny:
353   case BuiltinType::ARCUnbridgedCast:
354   case BuiltinType::PseudoObject:
355   case BuiltinType::ObjCId:
356   case BuiltinType::ObjCClass:
357   case BuiltinType::ObjCSel:
358 #define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
359   case BuiltinType::Id:
360 #include "clang/Basic/OpenCLImageTypes.def"
361   case BuiltinType::OCLSampler:
362   case BuiltinType::OCLEvent:
363   case BuiltinType::OCLClkEvent:
364   case BuiltinType::OCLQueue:
365   case BuiltinType::OCLReserveID:
366   case BuiltinType::BuiltinFn:
367   case BuiltinType::OMPArraySection:
368     return TST_unspecified;
369   }
370 
371   llvm_unreachable("Invalid BuiltinType Kind!");
372 }
373 
374 TypeLoc TypeLoc::IgnoreParensImpl(TypeLoc TL) {
375   while (ParenTypeLoc PTL = TL.getAs<ParenTypeLoc>())
376     TL = PTL.getInnerLoc();
377   return TL;
378 }
379 
380 SourceLocation TypeLoc::findNullabilityLoc() const {
381   if (auto attributedLoc = getAs<AttributedTypeLoc>()) {
382     if (attributedLoc.getAttrKind() == AttributedType::attr_nullable ||
383         attributedLoc.getAttrKind() == AttributedType::attr_nonnull ||
384         attributedLoc.getAttrKind() == AttributedType::attr_null_unspecified)
385       return attributedLoc.getAttrNameLoc();
386   }
387 
388   return {};
389 }
390 
391 TypeLoc TypeLoc::findExplicitQualifierLoc() const {
392   // Qualified types.
393   if (auto qual = getAs<QualifiedTypeLoc>())
394     return qual;
395 
396   TypeLoc loc = IgnoreParens();
397 
398   // Attributed types.
399   if (auto attr = loc.getAs<AttributedTypeLoc>()) {
400     if (attr.isQualifier()) return attr;
401     return attr.getModifiedLoc().findExplicitQualifierLoc();
402   }
403 
404   // C11 _Atomic types.
405   if (auto atomic = loc.getAs<AtomicTypeLoc>()) {
406     return atomic;
407   }
408 
409   return {};
410 }
411 
412 void ObjCTypeParamTypeLoc::initializeLocal(ASTContext &Context,
413                                            SourceLocation Loc) {
414   setNameLoc(Loc);
415   if (!getNumProtocols()) return;
416 
417   setProtocolLAngleLoc(Loc);
418   setProtocolRAngleLoc(Loc);
419   for (unsigned i = 0, e = getNumProtocols(); i != e; ++i)
420     setProtocolLoc(i, Loc);
421 }
422 
423 void ObjCObjectTypeLoc::initializeLocal(ASTContext &Context,
424                                         SourceLocation Loc) {
425   setHasBaseTypeAsWritten(true);
426   setTypeArgsLAngleLoc(Loc);
427   setTypeArgsRAngleLoc(Loc);
428   for (unsigned i = 0, e = getNumTypeArgs(); i != e; ++i) {
429     setTypeArgTInfo(i,
430                    Context.getTrivialTypeSourceInfo(
431                      getTypePtr()->getTypeArgsAsWritten()[i], Loc));
432   }
433   setProtocolLAngleLoc(Loc);
434   setProtocolRAngleLoc(Loc);
435   for (unsigned i = 0, e = getNumProtocols(); i != e; ++i)
436     setProtocolLoc(i, Loc);
437 }
438 
439 void TypeOfTypeLoc::initializeLocal(ASTContext &Context,
440                                        SourceLocation Loc) {
441   TypeofLikeTypeLoc<TypeOfTypeLoc, TypeOfType, TypeOfTypeLocInfo>
442       ::initializeLocal(Context, Loc);
443   this->getLocalData()->UnderlyingTInfo = Context.getTrivialTypeSourceInfo(
444       getUnderlyingType(), Loc);
445 }
446 
447 void UnaryTransformTypeLoc::initializeLocal(ASTContext &Context,
448                                        SourceLocation Loc) {
449     setKWLoc(Loc);
450     setRParenLoc(Loc);
451     setLParenLoc(Loc);
452     this->setUnderlyingTInfo(
453         Context.getTrivialTypeSourceInfo(getTypePtr()->getBaseType(), Loc));
454 }
455 
456 void ElaboratedTypeLoc::initializeLocal(ASTContext &Context,
457                                         SourceLocation Loc) {
458   setElaboratedKeywordLoc(Loc);
459   NestedNameSpecifierLocBuilder Builder;
460   Builder.MakeTrivial(Context, getTypePtr()->getQualifier(), Loc);
461   setQualifierLoc(Builder.getWithLocInContext(Context));
462 }
463 
464 void DependentNameTypeLoc::initializeLocal(ASTContext &Context,
465                                            SourceLocation Loc) {
466   setElaboratedKeywordLoc(Loc);
467   NestedNameSpecifierLocBuilder Builder;
468   Builder.MakeTrivial(Context, getTypePtr()->getQualifier(), Loc);
469   setQualifierLoc(Builder.getWithLocInContext(Context));
470   setNameLoc(Loc);
471 }
472 
473 void
474 DependentTemplateSpecializationTypeLoc::initializeLocal(ASTContext &Context,
475                                                         SourceLocation Loc) {
476   setElaboratedKeywordLoc(Loc);
477   if (getTypePtr()->getQualifier()) {
478     NestedNameSpecifierLocBuilder Builder;
479     Builder.MakeTrivial(Context, getTypePtr()->getQualifier(), Loc);
480     setQualifierLoc(Builder.getWithLocInContext(Context));
481   } else {
482     setQualifierLoc(NestedNameSpecifierLoc());
483   }
484   setTemplateKeywordLoc(Loc);
485   setTemplateNameLoc(Loc);
486   setLAngleLoc(Loc);
487   setRAngleLoc(Loc);
488   TemplateSpecializationTypeLoc::initializeArgLocs(Context, getNumArgs(),
489                                                    getTypePtr()->getArgs(),
490                                                    getArgInfos(), Loc);
491 }
492 
493 void TemplateSpecializationTypeLoc::initializeArgLocs(ASTContext &Context,
494                                                       unsigned NumArgs,
495                                                   const TemplateArgument *Args,
496                                               TemplateArgumentLocInfo *ArgInfos,
497                                                       SourceLocation Loc) {
498   for (unsigned i = 0, e = NumArgs; i != e; ++i) {
499     switch (Args[i].getKind()) {
500     case TemplateArgument::Null:
501       llvm_unreachable("Impossible TemplateArgument");
502 
503     case TemplateArgument::Integral:
504     case TemplateArgument::Declaration:
505     case TemplateArgument::NullPtr:
506       ArgInfos[i] = TemplateArgumentLocInfo();
507       break;
508 
509     case TemplateArgument::Expression:
510       ArgInfos[i] = TemplateArgumentLocInfo(Args[i].getAsExpr());
511       break;
512 
513     case TemplateArgument::Type:
514       ArgInfos[i] = TemplateArgumentLocInfo(
515                           Context.getTrivialTypeSourceInfo(Args[i].getAsType(),
516                                                            Loc));
517       break;
518 
519     case TemplateArgument::Template:
520     case TemplateArgument::TemplateExpansion: {
521       NestedNameSpecifierLocBuilder Builder;
522       TemplateName Template = Args[i].getAsTemplateOrTemplatePattern();
523       if (DependentTemplateName *DTN = Template.getAsDependentTemplateName())
524         Builder.MakeTrivial(Context, DTN->getQualifier(), Loc);
525       else if (QualifiedTemplateName *QTN = Template.getAsQualifiedTemplateName())
526         Builder.MakeTrivial(Context, QTN->getQualifier(), Loc);
527 
528       ArgInfos[i] = TemplateArgumentLocInfo(
529           Builder.getWithLocInContext(Context), Loc,
530           Args[i].getKind() == TemplateArgument::Template ? SourceLocation()
531                                                           : Loc);
532       break;
533     }
534 
535     case TemplateArgument::Pack:
536       ArgInfos[i] = TemplateArgumentLocInfo();
537       break;
538     }
539   }
540 }
541