clang  6.0.0svn
Scope.cpp
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1 //===- Scope.cpp - Lexical scope information --------------------*- C++ -*-===//
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 implements the Scope class, which is used for recording
11 // information about a lexical scope.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "clang/Sema/Scope.h"
16 #include "clang/AST/Decl.h"
17 #include "llvm/Support/raw_ostream.h"
18 
19 using namespace clang;
20 
21 void Scope::setFlags(Scope *parent, unsigned flags) {
22  AnyParent = parent;
23  Flags = flags;
24 
25  if (parent && !(flags & FnScope)) {
26  BreakParent = parent->BreakParent;
27  ContinueParent = parent->ContinueParent;
28  } else {
29  // Control scopes do not contain the contents of nested function scopes for
30  // control flow purposes.
31  BreakParent = ContinueParent = nullptr;
32  }
33 
34  if (parent) {
35  Depth = parent->Depth + 1;
36  PrototypeDepth = parent->PrototypeDepth;
37  PrototypeIndex = 0;
38  FnParent = parent->FnParent;
39  BlockParent = parent->BlockParent;
40  TemplateParamParent = parent->TemplateParamParent;
41  MSLastManglingParent = parent->MSLastManglingParent;
42  MSCurManglingNumber = getMSLastManglingNumber();
43  if ((Flags & (FnScope | ClassScope | BlockScope | TemplateParamScope |
45  0)
46  Flags |= parent->getFlags() & OpenMPSimdDirectiveScope;
47  } else {
48  Depth = 0;
49  PrototypeDepth = 0;
50  PrototypeIndex = 0;
51  MSLastManglingParent = FnParent = BlockParent = nullptr;
52  TemplateParamParent = nullptr;
53  MSLastManglingNumber = 1;
54  MSCurManglingNumber = 1;
55  }
56 
57  // If this scope is a function or contains breaks/continues, remember it.
58  if (flags & FnScope) FnParent = this;
59  // The MS mangler uses the number of scopes that can hold declarations as
60  // part of an external name.
61  if (Flags & (ClassScope | FnScope)) {
62  MSLastManglingNumber = getMSLastManglingNumber();
63  MSLastManglingParent = this;
64  MSCurManglingNumber = 1;
65  }
66  if (flags & BreakScope) BreakParent = this;
67  if (flags & ContinueScope) ContinueParent = this;
68  if (flags & BlockScope) BlockParent = this;
69  if (flags & TemplateParamScope) TemplateParamParent = this;
70 
71  // If this is a prototype scope, record that.
72  if (flags & FunctionPrototypeScope) PrototypeDepth++;
73 
74  if (flags & DeclScope) {
75  if (flags & FunctionPrototypeScope)
76  ; // Prototype scopes are uninteresting.
77  else if ((flags & ClassScope) && getParent()->isClassScope())
78  ; // Nested class scopes aren't ambiguous.
79  else if ((flags & ClassScope) && getParent()->getFlags() == DeclScope)
80  ; // Classes inside of namespaces aren't ambiguous.
81  else if ((flags & EnumScope))
82  ; // Don't increment for enum scopes.
83  else
85  }
86 }
87 
88 void Scope::Init(Scope *parent, unsigned flags) {
89  setFlags(parent, flags);
90 
91  DeclsInScope.clear();
92  UsingDirectives.clear();
93  Entity = nullptr;
94  ErrorTrap.reset();
95  NRVO.setPointerAndInt(nullptr, 0);
96 }
97 
99  const Scope *S = this;
100  while (S) {
101  if (S->isFunctionPrototypeScope())
102  return true;
103  S = S->getParent();
104  }
105  return false;
106 }
107 
108 void Scope::AddFlags(unsigned FlagsToSet) {
109  assert((FlagsToSet & ~(BreakScope | ContinueScope)) == 0 &&
110  "Unsupported scope flags");
111  if (FlagsToSet & BreakScope) {
112  assert((Flags & BreakScope) == 0 && "Already set");
113  BreakParent = this;
114  }
115  if (FlagsToSet & ContinueScope) {
116  assert((Flags & ContinueScope) == 0 && "Already set");
117  ContinueParent = this;
118  }
119  Flags |= FlagsToSet;
120 }
121 
123  if (VarDecl *Candidate = NRVO.getPointer()) {
124  if (isDeclScope(Candidate))
125  Candidate->setNRVOVariable(true);
126  }
127 
128  if (getEntity())
129  return;
130 
131  if (NRVO.getInt())
132  getParent()->setNoNRVO();
133  else if (NRVO.getPointer())
134  getParent()->addNRVOCandidate(NRVO.getPointer());
135 }
136 
137 LLVM_DUMP_METHOD void Scope::dump() const { dumpImpl(llvm::errs()); }
138 
139 void Scope::dumpImpl(raw_ostream &OS) const {
140  unsigned Flags = getFlags();
141  bool HasFlags = Flags != 0;
142 
143  if (HasFlags)
144  OS << "Flags: ";
145 
146  while (Flags) {
147  if (Flags & FnScope) {
148  OS << "FnScope";
149  Flags &= ~FnScope;
150  } else if (Flags & BreakScope) {
151  OS << "BreakScope";
152  Flags &= ~BreakScope;
153  } else if (Flags & ContinueScope) {
154  OS << "ContinueScope";
155  Flags &= ~ContinueScope;
156  } else if (Flags & DeclScope) {
157  OS << "DeclScope";
158  Flags &= ~DeclScope;
159  } else if (Flags & ControlScope) {
160  OS << "ControlScope";
161  Flags &= ~ControlScope;
162  } else if (Flags & ClassScope) {
163  OS << "ClassScope";
164  Flags &= ~ClassScope;
165  } else if (Flags & BlockScope) {
166  OS << "BlockScope";
167  Flags &= ~BlockScope;
168  } else if (Flags & TemplateParamScope) {
169  OS << "TemplateParamScope";
170  Flags &= ~TemplateParamScope;
171  } else if (Flags & FunctionPrototypeScope) {
172  OS << "FunctionPrototypeScope";
173  Flags &= ~FunctionPrototypeScope;
174  } else if (Flags & FunctionDeclarationScope) {
175  OS << "FunctionDeclarationScope";
176  Flags &= ~FunctionDeclarationScope;
177  } else if (Flags & AtCatchScope) {
178  OS << "AtCatchScope";
179  Flags &= ~AtCatchScope;
180  } else if (Flags & ObjCMethodScope) {
181  OS << "ObjCMethodScope";
182  Flags &= ~ObjCMethodScope;
183  } else if (Flags & SwitchScope) {
184  OS << "SwitchScope";
185  Flags &= ~SwitchScope;
186  } else if (Flags & TryScope) {
187  OS << "TryScope";
188  Flags &= ~TryScope;
189  } else if (Flags & FnTryCatchScope) {
190  OS << "FnTryCatchScope";
191  Flags &= ~FnTryCatchScope;
192  } else if (Flags & SEHTryScope) {
193  OS << "SEHTryScope";
194  Flags &= ~SEHTryScope;
195  } else if (Flags & SEHExceptScope) {
196  OS << "SEHExceptScope";
197  Flags &= ~SEHExceptScope;
198  } else if (Flags & OpenMPDirectiveScope) {
199  OS << "OpenMPDirectiveScope";
200  Flags &= ~OpenMPDirectiveScope;
201  } else if (Flags & OpenMPLoopDirectiveScope) {
202  OS << "OpenMPLoopDirectiveScope";
203  Flags &= ~OpenMPLoopDirectiveScope;
204  } else if (Flags & OpenMPSimdDirectiveScope) {
205  OS << "OpenMPSimdDirectiveScope";
206  Flags &= ~OpenMPSimdDirectiveScope;
207  }
208 
209  if (Flags)
210  OS << " | ";
211  }
212  if (HasFlags)
213  OS << '\n';
214 
215  if (const Scope *Parent = getParent())
216  OS << "Parent: (clang::Scope*)" << Parent << '\n';
217 
218  OS << "Depth: " << Depth << '\n';
219  OS << "MSLastManglingNumber: " << getMSLastManglingNumber() << '\n';
220  OS << "MSCurManglingNumber: " << getMSCurManglingNumber() << '\n';
221  if (const DeclContext *DC = getEntity())
222  OS << "Entity : (clang::DeclContext*)" << DC << '\n';
223 
224  if (NRVO.getInt())
225  OS << "NRVO not allowed\n";
226  else if (NRVO.getPointer())
227  OS << "NRVO candidate : (clang::VarDecl*)" << NRVO.getPointer() << '\n';
228 }
void AddFlags(unsigned Flags)
Sets up the specified scope flags and adjusts the scope state variables accordingly.
Definition: Scope.cpp:108
This is the scope of a C++ try statement.
Definition: Scope.h:100
This is a scope that corresponds to the parameters within a function prototype.
Definition: Scope.h:80
bool containedInPrototypeScope() const
containedInPrototypeScope - Return true if this or a parent scope is a FunctionPrototypeScope.
Definition: Scope.cpp:98
This is a while, do, switch, for, etc that can have break statements embedded into it...
Definition: Scope.h:50
This indicates that the scope corresponds to a function, which means that labels are set here...
Definition: Scope.h:46
VarDecl - An instance of this class is created to represent a variable declaration or definition...
Definition: Decl.h:771
void setNoNRVO()
Definition: Scope.h:473
The controlling scope in a if/switch/while/for statement.
Definition: Scope.h:61
This is a scope that corresponds to a block/closure object.
Definition: Scope.h:70
bool isFunctionPrototypeScope() const
isFunctionPrototypeScope - Return true if this scope is a function prototype scope.
Definition: Scope.h:374
This scope corresponds to an enum.
Definition: Scope.h:117
This is a scope that corresponds to a switch statement.
Definition: Scope.h:97
This is a while, do, for, which can have continue statements embedded into it.
Definition: Scope.h:54
unsigned getMSLastManglingNumber() const
Definition: Scope.h:300
Scope - A scope is a transient data structure that is used while parsing the program.
Definition: Scope.h:39
void incrementMSManglingNumber()
Definition: Scope.h:286
NodeId Parent
Definition: ASTDiff.cpp:192
unsigned getFlags() const
getFlags - Return the flags for this scope.
Definition: Scope.h:213
bool isDeclScope(Decl *D)
isDeclScope - Return true if this is the scope that the specified decl is declared in...
Definition: Scope.h:312
DeclContext * getEntity() const
Definition: Scope.h:316
This is the scope of OpenMP executable directive.
Definition: Scope.h:106
This scope corresponds to an SEH try.
Definition: Scope.h:120
This scope corresponds to an SEH except.
Definition: Scope.h:123
bool isClassScope() const
isClassScope - Return true if this scope is a class/struct/union scope.
Definition: Scope.h:329
This is a scope that corresponds to the parameters within a function prototype for a function declara...
Definition: Scope.h:86
unsigned getMSCurManglingNumber() const
Definition: Scope.h:306
This is a scope that corresponds to the Objective-C @catch statement.
Definition: Scope.h:90
void reset()
Set to initial state of "no errors occurred".
Definition: Diagnostic.h:931
void Init(Scope *parent, unsigned flags)
Init - This is used by the parser to implement scope caching.
Definition: Scope.cpp:88
The scope of a struct/union/class definition.
Definition: Scope.h:64
Dataflow Directional Tag Classes.
DeclContext - This is used only as base class of specific decl types that can act as declaration cont...
Definition: DeclBase.h:1224
This is the scope of some OpenMP simd directive.
Definition: Scope.h:114
const Scope * getParent() const
getParent - Return the scope that this is nested in.
Definition: Scope.h:221
void addNRVOCandidate(VarDecl *VD)
Definition: Scope.h:462
This is a scope that corresponds to the template parameters of a C++ template.
Definition: Scope.h:76
void dumpImpl(raw_ostream &OS) const
Definition: Scope.cpp:139
void mergeNRVOIntoParent()
Definition: Scope.cpp:122
This is the scope for a function-level C++ try or catch scope.
Definition: Scope.h:103
void dump() const
Definition: Scope.cpp:137
This is a scope that can contain a declaration.
Definition: Scope.h:58
This is the scope of some OpenMP loop directive.
Definition: Scope.h:109
This scope corresponds to an Objective-C method body.
Definition: Scope.h:94