clang  8.0.0svn
Builtins.h
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1 //===--- Builtins.h - Builtin function header -------------------*- 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 /// \file
11 /// Defines enum values for all the target-independent builtin
12 /// functions.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_CLANG_BASIC_BUILTINS_H
17 #define LLVM_CLANG_BASIC_BUILTINS_H
18 
19 #include "llvm/ADT/ArrayRef.h"
20 #include <cstring>
21 
22 // VC++ defines 'alloca' as an object-like macro, which interferes with our
23 // builtins.
24 #undef alloca
25 
26 namespace clang {
27 class TargetInfo;
28 class IdentifierTable;
29 class ASTContext;
30 class QualType;
31 class LangOptions;
32 
33 enum LanguageID {
34  GNU_LANG = 0x1, // builtin requires GNU mode.
35  C_LANG = 0x2, // builtin for c only.
36  CXX_LANG = 0x4, // builtin for cplusplus only.
37  OBJC_LANG = 0x8, // builtin for objective-c and objective-c++
38  MS_LANG = 0x10, // builtin requires MS mode.
39  OCLC20_LANG = 0x20, // builtin for OpenCL C 2.0 only.
40  OCLC1X_LANG = 0x40, // builtin for OpenCL C 1.x only.
41  OMP_LANG = 0x80, // builtin requires OpenMP.
42  ALL_LANGUAGES = C_LANG | CXX_LANG | OBJC_LANG, // builtin for all languages.
43  ALL_GNU_LANGUAGES = ALL_LANGUAGES | GNU_LANG, // builtin requires GNU mode.
44  ALL_MS_LANGUAGES = ALL_LANGUAGES | MS_LANG, // builtin requires MS mode.
45  ALL_OCLC_LANGUAGES = OCLC1X_LANG | OCLC20_LANG // builtin for OCLC languages.
46 };
47 
48 namespace Builtin {
49 enum ID {
50  NotBuiltin = 0, // This is not a builtin function.
51 #define BUILTIN(ID, TYPE, ATTRS) BI##ID,
52 #include "clang/Basic/Builtins.def"
54 };
55 
56 struct Info {
57  const char *Name, *Type, *Attributes, *HeaderName;
59  const char *Features;
60 };
61 
62 /// Holds information about both target-independent and
63 /// target-specific builtins, allowing easy queries by clients.
64 ///
65 /// Builtins from an optional auxiliary target are stored in
66 /// AuxTSRecords. Their IDs are shifted up by TSRecords.size() and need to
67 /// be translated back with getAuxBuiltinID() before use.
68 class Context {
69  llvm::ArrayRef<Info> TSRecords;
70  llvm::ArrayRef<Info> AuxTSRecords;
71 
72 public:
73  Context() {}
74 
75  /// Perform target-specific initialization
76  /// \param AuxTarget Target info to incorporate builtins from. May be nullptr.
77  void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget);
78 
79  /// Mark the identifiers for all the builtins with their
80  /// appropriate builtin ID # and mark any non-portable builtin identifiers as
81  /// such.
82  void initializeBuiltins(IdentifierTable &Table, const LangOptions& LangOpts);
83 
84  /// Return the identifier name for the specified builtin,
85  /// e.g. "__builtin_abs".
86  const char *getName(unsigned ID) const {
87  return getRecord(ID).Name;
88  }
89 
90  /// Get the type descriptor string for the specified builtin.
91  const char *getTypeString(unsigned ID) const {
92  return getRecord(ID).Type;
93  }
94 
95  /// Return true if this function is a target-specific builtin.
96  bool isTSBuiltin(unsigned ID) const {
97  return ID >= Builtin::FirstTSBuiltin;
98  }
99 
100  /// Return true if this function has no side effects.
101  bool isPure(unsigned ID) const {
102  return strchr(getRecord(ID).Attributes, 'U') != nullptr;
103  }
104 
105  /// Return true if this function has no side effects and doesn't
106  /// read memory.
107  bool isConst(unsigned ID) const {
108  return strchr(getRecord(ID).Attributes, 'c') != nullptr;
109  }
110 
111  /// Return true if we know this builtin never throws an exception.
112  bool isNoThrow(unsigned ID) const {
113  return strchr(getRecord(ID).Attributes, 'n') != nullptr;
114  }
115 
116  /// Return true if we know this builtin never returns.
117  bool isNoReturn(unsigned ID) const {
118  return strchr(getRecord(ID).Attributes, 'r') != nullptr;
119  }
120 
121  /// Return true if we know this builtin can return twice.
122  bool isReturnsTwice(unsigned ID) const {
123  return strchr(getRecord(ID).Attributes, 'j') != nullptr;
124  }
125 
126  /// Returns true if this builtin does not perform the side-effects
127  /// of its arguments.
128  bool isUnevaluated(unsigned ID) const {
129  return strchr(getRecord(ID).Attributes, 'u') != nullptr;
130  }
131 
132  /// Return true if this is a builtin for a libc/libm function,
133  /// with a "__builtin_" prefix (e.g. __builtin_abs).
134  bool isLibFunction(unsigned ID) const {
135  return strchr(getRecord(ID).Attributes, 'F') != nullptr;
136  }
137 
138  /// Determines whether this builtin is a predefined libc/libm
139  /// function, such as "malloc", where we know the signature a
140  /// priori.
141  bool isPredefinedLibFunction(unsigned ID) const {
142  return strchr(getRecord(ID).Attributes, 'f') != nullptr;
143  }
144 
145  /// Returns true if this builtin requires appropriate header in other
146  /// compilers. In Clang it will work even without including it, but we can emit
147  /// a warning about missing header.
148  bool isHeaderDependentFunction(unsigned ID) const {
149  return strchr(getRecord(ID).Attributes, 'h') != nullptr;
150  }
151 
152  /// Determines whether this builtin is a predefined compiler-rt/libgcc
153  /// function, such as "__clear_cache", where we know the signature a
154  /// priori.
155  bool isPredefinedRuntimeFunction(unsigned ID) const {
156  return strchr(getRecord(ID).Attributes, 'i') != nullptr;
157  }
158 
159  /// Determines whether this builtin has custom typechecking.
160  bool hasCustomTypechecking(unsigned ID) const {
161  return strchr(getRecord(ID).Attributes, 't') != nullptr;
162  }
163 
164  /// Determines whether this builtin has a result or any arguments which
165  /// are pointer types.
166  bool hasPtrArgsOrResult(unsigned ID) const {
167  return strchr(getRecord(ID).Type, '*') != nullptr;
168  }
169 
170  /// Return true if this builtin has a result or any arguments which are
171  /// reference types.
172  bool hasReferenceArgsOrResult(unsigned ID) const {
173  return strchr(getRecord(ID).Type, '&') != nullptr ||
174  strchr(getRecord(ID).Type, 'A') != nullptr;
175  }
176 
177  /// Completely forget that the given ID was ever considered a builtin,
178  /// e.g., because the user provided a conflicting signature.
179  void forgetBuiltin(unsigned ID, IdentifierTable &Table);
180 
181  /// If this is a library function that comes from a specific
182  /// header, retrieve that header name.
183  const char *getHeaderName(unsigned ID) const {
184  return getRecord(ID).HeaderName;
185  }
186 
187  /// Determine whether this builtin is like printf in its
188  /// formatting rules and, if so, set the index to the format string
189  /// argument and whether this function as a va_list argument.
190  bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);
191 
192  /// Determine whether this builtin is like scanf in its
193  /// formatting rules and, if so, set the index to the format string
194  /// argument and whether this function as a va_list argument.
195  bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);
196 
197  /// Return true if this function has no side effects and doesn't
198  /// read memory, except for possibly errno.
199  ///
200  /// Such functions can be const when the MathErrno lang option is disabled.
201  bool isConstWithoutErrno(unsigned ID) const {
202  return strchr(getRecord(ID).Attributes, 'e') != nullptr;
203  }
204 
205  const char *getRequiredFeatures(unsigned ID) const {
206  return getRecord(ID).Features;
207  }
208 
209  unsigned getRequiredVectorWidth(unsigned ID) const;
210 
211  /// Return true if builtin ID belongs to AuxTarget.
212  bool isAuxBuiltinID(unsigned ID) const {
213  return ID >= (Builtin::FirstTSBuiltin + TSRecords.size());
214  }
215 
216  /// Return real builtin ID (i.e. ID it would have during compilation
217  /// for AuxTarget).
218  unsigned getAuxBuiltinID(unsigned ID) const { return ID - TSRecords.size(); }
219 
220  /// Returns true if this is a libc/libm function without the '__builtin_'
221  /// prefix.
222  static bool isBuiltinFunc(const char *Name);
223 
224  /// Returns true if this is a builtin that can be redeclared. Returns true
225  /// for non-builtins.
226  bool canBeRedeclared(unsigned ID) const;
227 
228 private:
229  const Info &getRecord(unsigned ID) const;
230 
231  /// Is this builtin supported according to the given language options?
232  bool builtinIsSupported(const Builtin::Info &BuiltinInfo,
233  const LangOptions &LangOpts);
234 
235  /// Helper function for isPrintfLike and isScanfLike.
236  bool isLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg,
237  const char *Fmt) const;
238 };
239 
240 }
241 
242 /// Kinds of BuiltinTemplateDecl.
244  /// This names the __make_integer_seq BuiltinTemplateDecl.
246 
247  /// This names the __type_pack_element BuiltinTemplateDecl.
249 };
250 
251 } // end namespace clang
252 #endif
const char * getHeaderName(unsigned ID) const
If this is a library function that comes from a specific header, retrieve that header name...
Definition: Builtins.h:183
bool isPure(unsigned ID) const
Return true if this function has no side effects.
Definition: Builtins.h:101
bool hasReferenceArgsOrResult(unsigned ID) const
Return true if this builtin has a result or any arguments which are reference types.
Definition: Builtins.h:172
bool isPredefinedLibFunction(unsigned ID) const
Determines whether this builtin is a predefined libc/libm function, such as "malloc", where we know the signature a priori.
Definition: Builtins.h:141
Holds information about both target-independent and target-specific builtins, allowing easy queries b...
Definition: Builtins.h:68
const char * Attributes
Definition: Builtins.h:57
static const Builtin::Info BuiltinInfo[]
Definition: Builtins.cpp:21
The base class of the type hierarchy.
Definition: Type.h:1414
const char * Name
Definition: Builtins.h:57
const char * getTypeString(unsigned ID) const
Get the type descriptor string for the specified builtin.
Definition: Builtins.h:91
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:50
bool isLibFunction(unsigned ID) const
Return true if this is a builtin for a libc/libm function, with a "__builtin_" prefix (e...
Definition: Builtins.h:134
bool isConstWithoutErrno(unsigned ID) const
Return true if this function has no side effects and doesn&#39;t read memory, except for possibly errno...
Definition: Builtins.h:201
unsigned getAuxBuiltinID(unsigned ID) const
Return real builtin ID (i.e.
Definition: Builtins.h:218
LanguageID Langs
Definition: Builtins.h:58
bool isUnevaluated(unsigned ID) const
Returns true if this builtin does not perform the side-effects of its arguments.
Definition: Builtins.h:128
const char * Type
Definition: Builtins.h:57
const char * getName(unsigned ID) const
Return the identifier name for the specified builtin, e.g.
Definition: Builtins.h:86
Exposes information about the current target.
Definition: TargetInfo.h:54
bool isNoReturn(unsigned ID) const
Return true if we know this builtin never returns.
Definition: Builtins.h:117
Implements an efficient mapping from strings to IdentifierInfo nodes.
bool isPredefinedRuntimeFunction(unsigned ID) const
Determines whether this builtin is a predefined compiler-rt/libgcc function, such as "__clear_cache"...
Definition: Builtins.h:155
const char * getRequiredFeatures(unsigned ID) const
Definition: Builtins.h:205
const char * HeaderName
Definition: Builtins.h:57
bool hasPtrArgsOrResult(unsigned ID) const
Determines whether this builtin has a result or any arguments which are pointer types.
Definition: Builtins.h:166
bool isAuxBuiltinID(unsigned ID) const
Return true if builtin ID belongs to AuxTarget.
Definition: Builtins.h:212
This names the __make_integer_seq BuiltinTemplateDecl.
Definition: Builtins.h:245
bool isConst(unsigned ID) const
Return true if this function has no side effects and doesn&#39;t read memory.
Definition: Builtins.h:107
BuiltinTemplateKind
Kinds of BuiltinTemplateDecl.
Definition: Builtins.h:243
bool isHeaderDependentFunction(unsigned ID) const
Returns true if this builtin requires appropriate header in other compilers.
Definition: Builtins.h:148
Dataflow Directional Tag Classes.
This names the __type_pack_element BuiltinTemplateDecl.
Definition: Builtins.h:248
const char * Features
Definition: Builtins.h:59
bool isNoThrow(unsigned ID) const
Return true if we know this builtin never throws an exception.
Definition: Builtins.h:112
bool isTSBuiltin(unsigned ID) const
Return true if this function is a target-specific builtin.
Definition: Builtins.h:96
bool hasCustomTypechecking(unsigned ID) const
Determines whether this builtin has custom typechecking.
Definition: Builtins.h:160
bool isReturnsTwice(unsigned ID) const
Return true if we know this builtin can return twice.
Definition: Builtins.h:122
LanguageID
Definition: Builtins.h:33