clang 10.0.0git

Builtins.h
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1 //===--- Builtins.h - Builtin function header -------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// Defines enum values for all the target-independent builtin
11 /// functions.
12 ///
13 //===----------------------------------------------------------------------===//
14
15 #ifndef LLVM_CLANG_BASIC_BUILTINS_H
16 #define LLVM_CLANG_BASIC_BUILTINS_H
17
18 #include "llvm/ADT/ArrayRef.h"
19 #include <cstring>
20
21 // VC++ defines 'alloca' as an object-like macro, which interferes with our
22 // builtins.
23 #undef alloca
24
25 namespace clang {
26 class TargetInfo;
27 class IdentifierTable;
28 class LangOptions;
29
30 enum LanguageID {
31 GNU_LANG = 0x1, // builtin requires GNU mode.
32 C_LANG = 0x2, // builtin for c only.
33 CXX_LANG = 0x4, // builtin for cplusplus only.
34 OBJC_LANG = 0x8, // builtin for objective-c and objective-c++
35 MS_LANG = 0x10, // builtin requires MS mode.
36 OCLC20_LANG = 0x20, // builtin for OpenCL C 2.0 only.
37 OCLC1X_LANG = 0x40, // builtin for OpenCL C 1.x only.
38 OMP_LANG = 0x80, // builtin requires OpenMP.
39 ALL_LANGUAGES = C_LANG | CXX_LANG | OBJC_LANG, // builtin for all languages.
40 ALL_GNU_LANGUAGES = ALL_LANGUAGES | GNU_LANG, // builtin requires GNU mode.
41 ALL_MS_LANGUAGES = ALL_LANGUAGES | MS_LANG, // builtin requires MS mode.
42 ALL_OCLC_LANGUAGES = OCLC1X_LANG | OCLC20_LANG // builtin for OCLC languages.
43 };
44
45 namespace Builtin {
46 enum ID {
47 NotBuiltin = 0, // This is not a builtin function.
48 #define BUILTIN(ID, TYPE, ATTRS) BI##ID,
49 #include "clang/Basic/Builtins.def"
50 FirstTSBuiltin
51 };
52
53 struct Info {
54 const char *Name, *Type, *Attributes, *HeaderName;
55 LanguageID Langs;
56 const char *Features;
57 };
58
59 /// Holds information about both target-independent and
60 /// target-specific builtins, allowing easy queries by clients.
61 ///
62 /// Builtins from an optional auxiliary target are stored in
63 /// AuxTSRecords. Their IDs are shifted up by TSRecords.size() and need to
64 /// be translated back with getAuxBuiltinID() before use.
65 class Context {
66 llvm::ArrayRef<Info> TSRecords;
67 llvm::ArrayRef<Info> AuxTSRecords;
68
69 public:
70 Context() {}
71
72 /// Perform target-specific initialization
73 /// \param AuxTarget Target info to incorporate builtins from. May be nullptr.
74 void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget);
75
76 /// Mark the identifiers for all the builtins with their
77 /// appropriate builtin ID # and mark any non-portable builtin identifiers as
78 /// such.
79 void initializeBuiltins(IdentifierTable &Table, const LangOptions& LangOpts);
80
81 /// Return the identifier name for the specified builtin,
82 /// e.g. "__builtin_abs".
83 const char *getName(unsigned ID) const {
84 return getRecord(ID).Name;
85 }
86
87 /// Get the type descriptor string for the specified builtin.
88 const char *getTypeString(unsigned ID) const {
89 return getRecord(ID).Type;
90 }
91
92 /// Return true if this function is a target-specific builtin.
93 bool isTSBuiltin(unsigned ID) const {
94 return ID >= Builtin::FirstTSBuiltin;
95 }
96
97 /// Return true if this function has no side effects.
98 bool isPure(unsigned ID) const {
99 return strchr(getRecord(ID).Attributes, 'U') != nullptr;
100 }
101
102 /// Return true if this function has no side effects and doesn't
103 /// read memory.
104 bool isConst(unsigned ID) const {
105 return strchr(getRecord(ID).Attributes, 'c') != nullptr;
106 }
107
108 /// Return true if we know this builtin never throws an exception.
109 bool isNoThrow(unsigned ID) const {
110 return strchr(getRecord(ID).Attributes, 'n') != nullptr;
111 }
112
113 /// Return true if we know this builtin never returns.
114 bool isNoReturn(unsigned ID) const {
115 return strchr(getRecord(ID).Attributes, 'r') != nullptr;
116 }
117
118 /// Return true if we know this builtin can return twice.
119 bool isReturnsTwice(unsigned ID) const {
120 return strchr(getRecord(ID).Attributes, 'j') != nullptr;
121 }
122
123 /// Returns true if this builtin does not perform the side-effects
124 /// of its arguments.
125 bool isUnevaluated(unsigned ID) const {
126 return strchr(getRecord(ID).Attributes, 'u') != nullptr;
127 }
128
129 /// Return true if this is a builtin for a libc/libm function,
130 /// with a "__builtin_" prefix (e.g. __builtin_abs).
131 bool isLibFunction(unsigned ID) const {
132 return strchr(getRecord(ID).Attributes, 'F') != nullptr;
133 }
134
135 /// Determines whether this builtin is a predefined libc/libm
136 /// function, such as "malloc", where we know the signature a
137 /// priori.
138 bool isPredefinedLibFunction(unsigned ID) const {
139 return strchr(getRecord(ID).Attributes, 'f') != nullptr;
140 }
141
142 /// Returns true if this builtin requires appropriate header in other
143 /// compilers. In Clang it will work even without including it, but we can emit
144 /// a warning about missing header.
145 bool isHeaderDependentFunction(unsigned ID) const {
146 return strchr(getRecord(ID).Attributes, 'h') != nullptr;
147 }
148
149 /// Determines whether this builtin is a predefined compiler-rt/libgcc
150 /// function, such as "__clear_cache", where we know the signature a
151 /// priori.
152 bool isPredefinedRuntimeFunction(unsigned ID) const {
153 return strchr(getRecord(ID).Attributes, 'i') != nullptr;
154 }
155
156 /// Determines whether this builtin has custom typechecking.
157 bool hasCustomTypechecking(unsigned ID) const {
158 return strchr(getRecord(ID).Attributes, 't') != nullptr;
159 }
160
161 /// Determines whether this builtin has a result or any arguments which
162 /// are pointer types.
163 bool hasPtrArgsOrResult(unsigned ID) const {
164 return strchr(getRecord(ID).Type, '*') != nullptr;
165 }
166
167 /// Return true if this builtin has a result or any arguments which are
168 /// reference types.
169 bool hasReferenceArgsOrResult(unsigned ID) const {
170 return strchr(getRecord(ID).Type, '&') != nullptr ||
171 strchr(getRecord(ID).Type, 'A') != nullptr;
172 }
173
174 /// Completely forget that the given ID was ever considered a builtin,
175 /// e.g., because the user provided a conflicting signature.
176 void forgetBuiltin(unsigned ID, IdentifierTable &Table);
177
178 /// If this is a library function that comes from a specific
179 /// header, retrieve that header name.
180 const char *getHeaderName(unsigned ID) const {
181 return getRecord(ID).HeaderName;
182 }
183
184 /// Determine whether this builtin is like printf in its
185 /// formatting rules and, if so, set the index to the format string
186 /// argument and whether this function as a va_list argument.
187 bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);
188
189 /// Determine whether this builtin is like scanf in its
190 /// formatting rules and, if so, set the index to the format string
191 /// argument and whether this function as a va_list argument.
192 bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg);
193
194 /// Determine whether this builtin has callback behavior (see
195 /// llvm::AbstractCallSites for details). If so, add the index to the
196 /// callback callee argument and the callback payload arguments.
197 bool performsCallback(unsigned ID,
198 llvm::SmallVectorImpl<int> &Encoding) const;
199
200 /// Return true if this function has no side effects and doesn't
201 /// read memory, except for possibly errno.
202 ///
203 /// Such functions can be const when the MathErrno lang option is disabled.
204 bool isConstWithoutErrno(unsigned ID) const {
205 return strchr(getRecord(ID).Attributes, 'e') != nullptr;
206 }
207
208 const char *getRequiredFeatures(unsigned ID) const {
209 return getRecord(ID).Features;
210 }
211
212 unsigned getRequiredVectorWidth(unsigned ID) const;
213
214 /// Return true if builtin ID belongs to AuxTarget.
215 bool isAuxBuiltinID(unsigned ID) const {
216 return ID >= (Builtin::FirstTSBuiltin + TSRecords.size());
217 }
218
219 /// Return real builtin ID (i.e. ID it would have during compilation
220 /// for AuxTarget).
221 unsigned getAuxBuiltinID(unsigned ID) const { return ID - TSRecords.size(); }
222
223 /// Returns true if this is a libc/libm function without the '__builtin_'
224 /// prefix.
225 static bool isBuiltinFunc(llvm::StringRef Name);
226
227 /// Returns true if this is a builtin that can be redeclared. Returns true
228 /// for non-builtins.
229 bool canBeRedeclared(unsigned ID) const;
230
231 private:
232 const Info &getRecord(unsigned ID) const;
233
234 /// Is this builtin supported according to the given language options?
235 bool builtinIsSupported(const Builtin::Info &BuiltinInfo,
236 const LangOptions &LangOpts);
237
238 /// Helper function for isPrintfLike and isScanfLike.
239 bool isLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg,
240 const char *Fmt) const;
241 };
242
243 }
244
245 /// Kinds of BuiltinTemplateDecl.
246 enum BuiltinTemplateKind : int {
247 /// This names the __make_integer_seq BuiltinTemplateDecl.
248 BTK__make_integer_seq,
249
250 /// This names the __type_pack_element BuiltinTemplateDecl.
251 BTK__type_pack_element
252 };
253
254 } // end namespace clang
255 #endif
clang::OCLC1X_LANG
Definition: Builtins.h:37
clang::Builtin::ID
ID
Definition: Builtins.h:46
clang::Builtin::Context::getHeaderName
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:180
clang::Builtin::Context::isPure
bool isPure(unsigned ID) const
Return true if this function has no side effects.
Definition: Builtins.h:98
clang::Builtin::Context::hasReferenceArgsOrResult
bool hasReferenceArgsOrResult(unsigned ID) const
Return true if this builtin has a result or any arguments which are reference types.
Definition: Builtins.h:169
clang::Builtin::Context::isPredefinedLibFunction
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:138
clang::Builtin::Context
Holds information about both target-independent and target-specific builtins, allowing easy queries b...
Definition: Builtins.h:65
clang::Builtin::Info::Attributes
const char * Attributes
Definition: Builtins.h:54
BuiltinInfo
static const Builtin::Info BuiltinInfo[]
Definition: Builtins.cpp:20
clang::Type
The base class of the type hierarchy.
Definition: Type.h:1450
clang::Builtin::Info::Name
const char * Name
Definition: Builtins.h:54
clang::MultiVersionKind::Target
clang::C_LANG
Definition: Builtins.h:32
clang::Builtin::Info
Definition: Builtins.h:53
clang::OMP_LANG
Definition: Builtins.h:38
clang::Builtin::Context::getTypeString
const char * getTypeString(unsigned ID) const
Get the type descriptor string for the specified builtin.
Definition: Builtins.h:88
clang::LangOptions
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:53
llvm::SmallVectorImpl
Definition: LLVM.h:36
clang::Builtin::Context::isLibFunction
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:131
clang::ALL_OCLC_LANGUAGES
Definition: Builtins.h:42
clang::Builtin::Context::isConstWithoutErrno
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:204
clang::Builtin::Context::getAuxBuiltinID
unsigned getAuxBuiltinID(unsigned ID) const
Return real builtin ID (i.e.
Definition: Builtins.h:221
clang::Builtin::Info::Langs
LanguageID Langs
Definition: Builtins.h:55
llvm::ArrayRef
Definition: LLVM.h:31
clang::Builtin::Context::isUnevaluated
bool isUnevaluated(unsigned ID) const
Returns true if this builtin does not perform the side-effects of its arguments.
Definition: Builtins.h:125
clang::Builtin::Context::Context
Context()
Definition: Builtins.h:70
clang::format::encoding::Encoding
Encoding
Definition: Encoding.h:27
clang::Builtin::Info::Type
const char * Type
Definition: Builtins.h:54
clang::Builtin::Context::getName
const char * getName(unsigned ID) const
Return the identifier name for the specified builtin, e.g.
Definition: Builtins.h:83
clang::TargetInfo
Exposes information about the current target.
Definition: TargetInfo.h:164
clang::Builtin::Context::isNoReturn
bool isNoReturn(unsigned ID) const
Return true if we know this builtin never returns.
Definition: Builtins.h:114
clang::IdentifierTable
Implements an efficient mapping from strings to IdentifierInfo nodes.
Definition: IdentifierTable.h:496
clang::Builtin::Context::isPredefinedRuntimeFunction
bool isPredefinedRuntimeFunction(unsigned ID) const
Determines whether this builtin is a predefined compiler-rt/libgcc function, such as "__clear_cache"...
Definition: Builtins.h:152
clang::Builtin::Context::getRequiredFeatures
const char * getRequiredFeatures(unsigned ID) const
Definition: Builtins.h:208
clang::Builtin::Info::HeaderName
const char * HeaderName
Definition: Builtins.h:54
clang::Builtin::Context::hasPtrArgsOrResult
bool hasPtrArgsOrResult(unsigned ID) const
Determines whether this builtin has a result or any arguments which are pointer types.
Definition: Builtins.h:163
clang::Builtin::Context::isAuxBuiltinID
bool isAuxBuiltinID(unsigned ID) const
Return true if builtin ID belongs to AuxTarget.
Definition: Builtins.h:215
clang::MS_LANG
Definition: Builtins.h:35
clang::Builtin::NotBuiltin
Definition: Builtins.h:47
clang::BTK__make_integer_seq
This names the __make_integer_seq BuiltinTemplateDecl.
Definition: Builtins.h:248
clang::Builtin::Context::isConst
bool isConst(unsigned ID) const
Return true if this function has no side effects and doesn&#39;t read memory.
Definition: Builtins.h:104
clang::BuiltinTemplateKind
BuiltinTemplateKind
Kinds of BuiltinTemplateDecl.
Definition: Builtins.h:246
clang::ALL_MS_LANGUAGES
Definition: Builtins.h:41
clang::Builtin::Context::isHeaderDependentFunction
bool isHeaderDependentFunction(unsigned ID) const
Returns true if this builtin requires appropriate header in other compilers.
Definition: Builtins.h:145
clang::OCLC20_LANG
Definition: Builtins.h:36
clang
Dataflow Directional Tag Classes.
Definition: CFGReachabilityAnalysis.h:21
clang::BTK__type_pack_element
This names the __type_pack_element BuiltinTemplateDecl.
Definition: Builtins.h:251
clang::Builtin::Info::Features
const char * Features
Definition: Builtins.h:56
clang::OBJC_LANG
Definition: Builtins.h:34
clang::Builtin::FirstTSBuiltin
Definition: Builtins.h:50
clang::Builtin::Context::isNoThrow
bool isNoThrow(unsigned ID) const
Return true if we know this builtin never throws an exception.
Definition: Builtins.h:109
clang::CXX_LANG
Definition: Builtins.h:33
clang::GNU_LANG
Definition: Builtins.h:31
clang::ALL_LANGUAGES
Definition: Builtins.h:39
clang::Builtin::Context::isTSBuiltin
bool isTSBuiltin(unsigned ID) const
Return true if this function is a target-specific builtin.
Definition: Builtins.h:93
clang::ALL_GNU_LANGUAGES
Definition: Builtins.h:40
clang::Builtin::Context::hasCustomTypechecking
bool hasCustomTypechecking(unsigned ID) const
Determines whether this builtin has custom typechecking.
Definition: Builtins.h:157
clang::Builtin::Context::isReturnsTwice
bool isReturnsTwice(unsigned ID) const
Return true if we know this builtin can return twice.
Definition: Builtins.h:119
clang::LanguageID
LanguageID
Definition: Builtins.h:30