xref: /freebsd/contrib/llvm-project/clang/lib/Basic/Attributes.cpp (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
1 //===--- Attributes.cpp ---------------------------------------------------===//
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 // This file implements the AttributeCommonInfo interface.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/Basic/Attributes.h"
14 #include "clang/Basic/AttrSubjectMatchRules.h"
15 #include "clang/Basic/IdentifierTable.h"
16 #include "clang/Basic/LangOptions.h"
17 #include "clang/Basic/ParsedAttrInfo.h"
18 #include "clang/Basic/TargetInfo.h"
19 
20 using namespace clang;
21 
22 static int hasAttributeImpl(AttributeCommonInfo::Syntax Syntax, StringRef Name,
23                             StringRef ScopeName, const TargetInfo &Target,
24                             const LangOptions &LangOpts) {
25 
26 #include "clang/Basic/AttrHasAttributeImpl.inc"
27 
28   return 0;
29 }
30 
31 int clang::hasAttribute(AttributeCommonInfo::Syntax Syntax,
32                         const IdentifierInfo *Scope, const IdentifierInfo *Attr,
33                         const TargetInfo &Target, const LangOptions &LangOpts) {
34   StringRef Name = Attr->getName();
35   // Normalize the attribute name, __foo__ becomes foo.
36   if (Name.size() >= 4 && Name.starts_with("__") && Name.ends_with("__"))
37     Name = Name.substr(2, Name.size() - 4);
38 
39   // Normalize the scope name, but only for gnu and clang attributes.
40   StringRef ScopeName = Scope ? Scope->getName() : "";
41   if (ScopeName == "__gnu__")
42     ScopeName = "gnu";
43   else if (ScopeName == "_Clang")
44     ScopeName = "clang";
45 
46   // As a special case, look for the omp::sequence and omp::directive
47   // attributes. We support those, but not through the typical attribute
48   // machinery that goes through TableGen. We support this in all OpenMP modes
49   // so long as double square brackets are enabled.
50   if (LangOpts.OpenMP && ScopeName == "omp")
51     return (Name == "directive" || Name == "sequence") ? 1 : 0;
52 
53   int res = hasAttributeImpl(Syntax, Name, ScopeName, Target, LangOpts);
54   if (res)
55     return res;
56 
57   // Check if any plugin provides this attribute.
58   for (auto &Ptr : getAttributePluginInstances())
59     if (Ptr->hasSpelling(Syntax, Name))
60       return 1;
61 
62   return 0;
63 }
64 
65 const char *attr::getSubjectMatchRuleSpelling(attr::SubjectMatchRule Rule) {
66   switch (Rule) {
67 #define ATTR_MATCH_RULE(NAME, SPELLING, IsAbstract)                            \
68   case attr::NAME:                                                             \
69     return SPELLING;
70 #include "clang/Basic/AttrSubMatchRulesList.inc"
71   }
72   llvm_unreachable("Invalid subject match rule");
73 }
74 
75 static StringRef
76 normalizeAttrScopeName(const IdentifierInfo *Scope,
77                        AttributeCommonInfo::Syntax SyntaxUsed) {
78   if (!Scope)
79     return "";
80 
81   // Normalize the "__gnu__" scope name to be "gnu" and the "_Clang" scope name
82   // to be "clang".
83   StringRef ScopeName = Scope->getName();
84   if (SyntaxUsed == AttributeCommonInfo::AS_CXX11 ||
85       SyntaxUsed == AttributeCommonInfo::AS_C23) {
86     if (ScopeName == "__gnu__")
87       ScopeName = "gnu";
88     else if (ScopeName == "_Clang")
89       ScopeName = "clang";
90   }
91   return ScopeName;
92 }
93 
94 static StringRef normalizeAttrName(const IdentifierInfo *Name,
95                                    StringRef NormalizedScopeName,
96                                    AttributeCommonInfo::Syntax SyntaxUsed) {
97   // Normalize the attribute name, __foo__ becomes foo. This is only allowable
98   // for GNU attributes, and attributes using the double square bracket syntax.
99   bool ShouldNormalize =
100       SyntaxUsed == AttributeCommonInfo::AS_GNU ||
101       ((SyntaxUsed == AttributeCommonInfo::AS_CXX11 ||
102         SyntaxUsed == AttributeCommonInfo::AS_C23) &&
103        (NormalizedScopeName.empty() || NormalizedScopeName == "gnu" ||
104         NormalizedScopeName == "clang"));
105   StringRef AttrName = Name->getName();
106   if (ShouldNormalize && AttrName.size() >= 4 && AttrName.starts_with("__") &&
107       AttrName.ends_with("__"))
108     AttrName = AttrName.slice(2, AttrName.size() - 2);
109 
110   return AttrName;
111 }
112 
113 bool AttributeCommonInfo::isGNUScope() const {
114   return ScopeName && (ScopeName->isStr("gnu") || ScopeName->isStr("__gnu__"));
115 }
116 
117 bool AttributeCommonInfo::isClangScope() const {
118   return ScopeName && (ScopeName->isStr("clang") || ScopeName->isStr("_Clang"));
119 }
120 
121 #include "clang/Sema/AttrParsedAttrKinds.inc"
122 
123 static SmallString<64> normalizeName(const IdentifierInfo *Name,
124                                      const IdentifierInfo *Scope,
125                                      AttributeCommonInfo::Syntax SyntaxUsed) {
126   StringRef ScopeName = normalizeAttrScopeName(Scope, SyntaxUsed);
127   StringRef AttrName = normalizeAttrName(Name, ScopeName, SyntaxUsed);
128 
129   SmallString<64> FullName = ScopeName;
130   if (!ScopeName.empty()) {
131     assert(SyntaxUsed == AttributeCommonInfo::AS_CXX11 ||
132            SyntaxUsed == AttributeCommonInfo::AS_C23);
133     FullName += "::";
134   }
135   FullName += AttrName;
136 
137   return FullName;
138 }
139 
140 AttributeCommonInfo::Kind
141 AttributeCommonInfo::getParsedKind(const IdentifierInfo *Name,
142                                    const IdentifierInfo *ScopeName,
143                                    Syntax SyntaxUsed) {
144   return ::getAttrKind(normalizeName(Name, ScopeName, SyntaxUsed), SyntaxUsed);
145 }
146 
147 std::string AttributeCommonInfo::getNormalizedFullName() const {
148   return static_cast<std::string>(
149       normalizeName(getAttrName(), getScopeName(), getSyntax()));
150 }
151 
152 unsigned AttributeCommonInfo::calculateAttributeSpellingListIndex() const {
153   // Both variables will be used in tablegen generated
154   // attribute spell list index matching code.
155   auto Syntax = static_cast<AttributeCommonInfo::Syntax>(getSyntax());
156   StringRef Scope = normalizeAttrScopeName(getScopeName(), Syntax);
157   StringRef Name = normalizeAttrName(getAttrName(), Scope, Syntax);
158 
159 #include "clang/Sema/AttrSpellingListIndex.inc"
160 }
161