1 //===--- Scope.h - Scope interface ------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the Scope interface.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_SEMA_SCOPE_H
15 #define LLVM_CLANG_SEMA_SCOPE_H
17 #include "clang/Basic/Diagnostic.h"
18 #include "llvm/ADT/SmallPtrSet.h"
19 #include "llvm/ADT/SmallVector.h"
24 class UsingDirectiveDecl;
26 /// Scope - A scope is a transient data structure that is used while parsing the
27 /// program. It assists with resolving identifiers to the appropriate
32 /// ScopeFlags - These are bitfields that are or'd together when creating a
33 /// scope, which defines the sorts of things the scope contains.
35 /// \brief This indicates that the scope corresponds to a function, which
36 /// means that labels are set here.
39 /// \brief This is a while, do, switch, for, etc that can have break
40 /// statements embedded into it.
43 /// \brief This is a while, do, for, which can have continue statements
47 /// \brief This is a scope that can contain a declaration. Some scopes
48 /// just contain loop constructs but don't contain decls.
51 /// \brief The controlling scope in a if/switch/while/for statement.
54 /// \brief The scope of a struct/union/class definition.
57 /// \brief This is a scope that corresponds to a block/closure object.
58 /// Blocks serve as top-level scopes for some objects like labels, they
59 /// also prevent things like break and continue. BlockScopes always have
60 /// the FnScope and DeclScope flags set as well.
63 /// \brief This is a scope that corresponds to the
64 /// template parameters of a C++ template. Template parameter
65 /// scope starts at the 'template' keyword and ends when the
66 /// template declaration ends.
67 TemplateParamScope = 0x80,
69 /// \brief This is a scope that corresponds to the
70 /// parameters within a function prototype.
71 FunctionPrototypeScope = 0x100,
73 /// \brief This is a scope that corresponds to the parameters within
74 /// a function prototype for a function declaration (as opposed to any
75 /// other kind of function declarator). Always has FunctionPrototypeScope
77 FunctionDeclarationScope = 0x200,
79 /// \brief This is a scope that corresponds to the Objective-C
80 /// \@catch statement.
83 /// \brief This scope corresponds to an Objective-C method body.
84 /// It always has FnScope and DeclScope set as well.
85 ObjCMethodScope = 0x800,
87 /// \brief This is a scope that corresponds to a switch statement.
90 /// \brief This is the scope of a C++ try statement.
93 /// \brief This is the scope for a function-level C++ try or catch scope.
94 FnTryCatchScope = 0x4000
97 /// The parent scope for this scope. This is null for the translation-unit
101 /// Depth - This is the depth of this scope. The translation-unit scope has
103 unsigned short Depth;
105 /// Flags - This contains a set of ScopeFlags, which indicates how the scope
106 /// interrelates with other control flow statements.
107 unsigned short Flags;
109 /// PrototypeDepth - This is the number of function prototype scopes
110 /// enclosing this scope, including this scope.
111 unsigned short PrototypeDepth;
113 /// PrototypeIndex - This is the number of parameters currently
114 /// declared in this scope.
115 unsigned short PrototypeIndex;
117 /// FnParent - If this scope has a parent scope that is a function body, this
118 /// pointer is non-null and points to it. This is used for label processing.
121 /// BreakParent/ContinueParent - This is a direct link to the innermost
122 /// BreakScope/ContinueScope which contains the contents of this scope
123 /// for control flow purposes (and might be this scope itself), or null
124 /// if there is no such scope.
125 Scope *BreakParent, *ContinueParent;
127 /// BlockParent - This is a direct link to the immediately containing
128 /// BlockScope if this scope is not one, or null if there is none.
131 /// TemplateParamParent - This is a direct link to the
132 /// immediately containing template parameter scope. In the
133 /// case of nested templates, template parameter scopes can have
134 /// other template parameter scopes as parents.
135 Scope *TemplateParamParent;
137 /// DeclsInScope - This keeps track of all declarations in this scope. When
138 /// the declaration is added to the scope, it is set as the current
139 /// declaration for the identifier in the IdentifierTable. When the scope is
140 /// popped, these declarations are removed from the IdentifierTable's notion
141 /// of current declaration. It is up to the current Action implementation to
142 /// implement these semantics.
143 typedef llvm::SmallPtrSet<Decl *, 32> DeclSetTy;
144 DeclSetTy DeclsInScope;
146 /// Entity - The entity with which this scope is associated. For
147 /// example, the entity of a class scope is the class itself, the
148 /// entity of a function scope is a function, etc. This field is
149 /// maintained by the Action implementation.
152 typedef SmallVector<UsingDirectiveDecl *, 2> UsingDirectivesTy;
153 UsingDirectivesTy UsingDirectives;
155 /// \brief Used to determine if errors occurred in this scope.
156 DiagnosticErrorTrap ErrorTrap;
159 Scope(Scope *Parent, unsigned ScopeFlags, DiagnosticsEngine &Diag)
161 Init(Parent, ScopeFlags);
164 /// getFlags - Return the flags for this scope.
166 unsigned getFlags() const { return Flags; }
167 void setFlags(unsigned F) { Flags = F; }
169 /// isBlockScope - Return true if this scope correspond to a closure.
170 bool isBlockScope() const { return Flags & BlockScope; }
172 /// getParent - Return the scope that this is nested in.
174 const Scope *getParent() const { return AnyParent; }
175 Scope *getParent() { return AnyParent; }
177 /// getFnParent - Return the closest scope that is a function body.
179 const Scope *getFnParent() const { return FnParent; }
180 Scope *getFnParent() { return FnParent; }
182 /// getContinueParent - Return the closest scope that a continue statement
183 /// would be affected by.
184 Scope *getContinueParent() {
185 return ContinueParent;
188 const Scope *getContinueParent() const {
189 return const_cast<Scope*>(this)->getContinueParent();
192 /// getBreakParent - Return the closest scope that a break statement
193 /// would be affected by.
194 Scope *getBreakParent() {
197 const Scope *getBreakParent() const {
198 return const_cast<Scope*>(this)->getBreakParent();
201 Scope *getBlockParent() { return BlockParent; }
202 const Scope *getBlockParent() const { return BlockParent; }
204 Scope *getTemplateParamParent() { return TemplateParamParent; }
205 const Scope *getTemplateParamParent() const { return TemplateParamParent; }
207 /// Returns the number of function prototype scopes in this scope
209 unsigned getFunctionPrototypeDepth() const {
210 return PrototypeDepth;
213 /// Return the number of parameters declared in this function
214 /// prototype, increasing it by one for the next call.
215 unsigned getNextFunctionPrototypeIndex() {
216 assert(isFunctionPrototypeScope());
217 return PrototypeIndex++;
220 typedef DeclSetTy::iterator decl_iterator;
221 decl_iterator decl_begin() const { return DeclsInScope.begin(); }
222 decl_iterator decl_end() const { return DeclsInScope.end(); }
223 bool decl_empty() const { return DeclsInScope.empty(); }
225 void AddDecl(Decl *D) {
226 DeclsInScope.insert(D);
229 void RemoveDecl(Decl *D) {
230 DeclsInScope.erase(D);
233 /// isDeclScope - Return true if this is the scope that the specified decl is
235 bool isDeclScope(Decl *D) {
236 return DeclsInScope.count(D) != 0;
239 void* getEntity() const { return Entity; }
240 void setEntity(void *E) { Entity = E; }
242 bool hasErrorOccurred() const { return ErrorTrap.hasErrorOccurred(); }
244 bool hasUnrecoverableErrorOccurred() const {
245 return ErrorTrap.hasUnrecoverableErrorOccurred();
248 /// isClassScope - Return true if this scope is a class/struct/union scope.
249 bool isClassScope() const {
250 return (getFlags() & Scope::ClassScope);
253 /// isInCXXInlineMethodScope - Return true if this scope is a C++ inline
254 /// method scope or is inside one.
255 bool isInCXXInlineMethodScope() const {
256 if (const Scope *FnS = getFnParent()) {
257 assert(FnS->getParent() && "TUScope not created?");
258 return FnS->getParent()->isClassScope();
263 /// isInObjcMethodScope - Return true if this scope is, or is contained in, an
264 /// Objective-C method body. Note that this method is not constant time.
265 bool isInObjcMethodScope() const {
266 for (const Scope *S = this; S; S = S->getParent()) {
267 // If this scope is an objc method scope, then we succeed.
268 if (S->getFlags() & ObjCMethodScope)
274 /// isTemplateParamScope - Return true if this scope is a C++
275 /// template parameter scope.
276 bool isTemplateParamScope() const {
277 return getFlags() & Scope::TemplateParamScope;
280 /// isFunctionPrototypeScope - Return true if this scope is a
281 /// function prototype scope.
282 bool isFunctionPrototypeScope() const {
283 return getFlags() & Scope::FunctionPrototypeScope;
286 /// isAtCatchScope - Return true if this scope is \@catch.
287 bool isAtCatchScope() const {
288 return getFlags() & Scope::AtCatchScope;
291 /// isSwitchScope - Return true if this scope is a switch scope.
292 bool isSwitchScope() const {
293 for (const Scope *S = this; S; S = S->getParent()) {
294 if (S->getFlags() & Scope::SwitchScope)
296 else if (S->getFlags() & (Scope::FnScope | Scope::ClassScope |
297 Scope::BlockScope | Scope::TemplateParamScope |
298 Scope::FunctionPrototypeScope |
299 Scope::AtCatchScope | Scope::ObjCMethodScope))
305 /// \brief Determine whether this scope is a C++ 'try' block.
306 bool isTryScope() const { return getFlags() & Scope::TryScope; }
308 /// containedInPrototypeScope - Return true if this or a parent scope
309 /// is a FunctionPrototypeScope.
310 bool containedInPrototypeScope() const;
312 typedef UsingDirectivesTy::iterator udir_iterator;
313 typedef UsingDirectivesTy::const_iterator const_udir_iterator;
315 void PushUsingDirective(UsingDirectiveDecl *UDir) {
316 UsingDirectives.push_back(UDir);
319 udir_iterator using_directives_begin() {
320 return UsingDirectives.begin();
323 udir_iterator using_directives_end() {
324 return UsingDirectives.end();
327 const_udir_iterator using_directives_begin() const {
328 return UsingDirectives.begin();
331 const_udir_iterator using_directives_end() const {
332 return UsingDirectives.end();
335 /// Init - This is used by the parser to implement scope caching.
337 void Init(Scope *parent, unsigned flags);
340 } // end namespace clang