1 //===--- Builtins.cpp - Builtin function implementation -------------------===//
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 various things for builtin functions.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "clang/Basic/Builtins.h"
14 #include "clang/Basic/IdentifierTable.h"
15 #include "clang/Basic/LangOptions.h"
16 #include "clang/Basic/TargetInfo.h"
17 #include "llvm/ADT/StringRef.h"
18 using namespace clang;
19
20 static const Builtin::Info BuiltinInfo[] = {
21 { "not a builtin function", nullptr, nullptr, nullptr, ALL_LANGUAGES,nullptr},
22 #define BUILTIN(ID, TYPE, ATTRS) \
23 { #ID, TYPE, ATTRS, nullptr, ALL_LANGUAGES, nullptr },
24 #define LANGBUILTIN(ID, TYPE, ATTRS, LANGS) \
25 { #ID, TYPE, ATTRS, nullptr, LANGS, nullptr },
26 #define LIBBUILTIN(ID, TYPE, ATTRS, HEADER, LANGS) \
27 { #ID, TYPE, ATTRS, HEADER, LANGS, nullptr },
28 #include "clang/Basic/Builtins.def"
29 };
30
getRecord(unsigned ID) const31 const Builtin::Info &Builtin::Context::getRecord(unsigned ID) const {
32 if (ID < Builtin::FirstTSBuiltin)
33 return BuiltinInfo[ID];
34 assert(((ID - Builtin::FirstTSBuiltin) <
35 (TSRecords.size() + AuxTSRecords.size())) &&
36 "Invalid builtin ID!");
37 if (isAuxBuiltinID(ID))
38 return AuxTSRecords[getAuxBuiltinID(ID) - Builtin::FirstTSBuiltin];
39 return TSRecords[ID - Builtin::FirstTSBuiltin];
40 }
41
InitializeTarget(const TargetInfo & Target,const TargetInfo * AuxTarget)42 void Builtin::Context::InitializeTarget(const TargetInfo &Target,
43 const TargetInfo *AuxTarget) {
44 assert(TSRecords.empty() && "Already initialized target?");
45 TSRecords = Target.getTargetBuiltins();
46 if (AuxTarget)
47 AuxTSRecords = AuxTarget->getTargetBuiltins();
48 }
49
isBuiltinFunc(llvm::StringRef FuncName)50 bool Builtin::Context::isBuiltinFunc(llvm::StringRef FuncName) {
51 for (unsigned i = Builtin::NotBuiltin + 1; i != Builtin::FirstTSBuiltin; ++i)
52 if (FuncName.equals(BuiltinInfo[i].Name))
53 return strchr(BuiltinInfo[i].Attributes, 'f') != nullptr;
54
55 return false;
56 }
57
builtinIsSupported(const Builtin::Info & BuiltinInfo,const LangOptions & LangOpts)58 bool Builtin::Context::builtinIsSupported(const Builtin::Info &BuiltinInfo,
59 const LangOptions &LangOpts) {
60 bool BuiltinsUnsupported =
61 (LangOpts.NoBuiltin || LangOpts.isNoBuiltinFunc(BuiltinInfo.Name)) &&
62 strchr(BuiltinInfo.Attributes, 'f');
63 bool MathBuiltinsUnsupported =
64 LangOpts.NoMathBuiltin && BuiltinInfo.HeaderName &&
65 llvm::StringRef(BuiltinInfo.HeaderName).equals("math.h");
66 bool GnuModeUnsupported = !LangOpts.GNUMode && (BuiltinInfo.Langs & GNU_LANG);
67 bool MSModeUnsupported =
68 !LangOpts.MicrosoftExt && (BuiltinInfo.Langs & MS_LANG);
69 bool ObjCUnsupported = !LangOpts.ObjC && BuiltinInfo.Langs == OBJC_LANG;
70 bool OclC1Unsupported = (LangOpts.OpenCLVersion / 100) != 1 &&
71 (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES ) == OCLC1X_LANG;
72 bool OclC2Unsupported =
73 (LangOpts.OpenCLVersion != 200 && !LangOpts.OpenCLCPlusPlus) &&
74 (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES) == OCLC20_LANG;
75 bool OclCUnsupported = !LangOpts.OpenCL &&
76 (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES);
77 bool OpenMPUnsupported = !LangOpts.OpenMP && BuiltinInfo.Langs == OMP_LANG;
78 bool CPlusPlusUnsupported =
79 !LangOpts.CPlusPlus && BuiltinInfo.Langs == CXX_LANG;
80 return !BuiltinsUnsupported && !MathBuiltinsUnsupported && !OclCUnsupported &&
81 !OclC1Unsupported && !OclC2Unsupported && !OpenMPUnsupported &&
82 !GnuModeUnsupported && !MSModeUnsupported && !ObjCUnsupported &&
83 !CPlusPlusUnsupported;
84 }
85
86 /// initializeBuiltins - Mark the identifiers for all the builtins with their
87 /// appropriate builtin ID # and mark any non-portable builtin identifiers as
88 /// such.
initializeBuiltins(IdentifierTable & Table,const LangOptions & LangOpts)89 void Builtin::Context::initializeBuiltins(IdentifierTable &Table,
90 const LangOptions& LangOpts) {
91 // Step #1: mark all target-independent builtins with their ID's.
92 for (unsigned i = Builtin::NotBuiltin+1; i != Builtin::FirstTSBuiltin; ++i)
93 if (builtinIsSupported(BuiltinInfo[i], LangOpts)) {
94 Table.get(BuiltinInfo[i].Name).setBuiltinID(i);
95 }
96
97 // Step #2: Register target-specific builtins.
98 for (unsigned i = 0, e = TSRecords.size(); i != e; ++i)
99 if (builtinIsSupported(TSRecords[i], LangOpts))
100 Table.get(TSRecords[i].Name).setBuiltinID(i + Builtin::FirstTSBuiltin);
101
102 // Step #3: Register target-specific builtins for AuxTarget.
103 for (unsigned i = 0, e = AuxTSRecords.size(); i != e; ++i)
104 Table.get(AuxTSRecords[i].Name)
105 .setBuiltinID(i + Builtin::FirstTSBuiltin + TSRecords.size());
106 }
107
forgetBuiltin(unsigned ID,IdentifierTable & Table)108 void Builtin::Context::forgetBuiltin(unsigned ID, IdentifierTable &Table) {
109 Table.get(getRecord(ID).Name).setBuiltinID(0);
110 }
111
getRequiredVectorWidth(unsigned ID) const112 unsigned Builtin::Context::getRequiredVectorWidth(unsigned ID) const {
113 const char *WidthPos = ::strchr(getRecord(ID).Attributes, 'V');
114 if (!WidthPos)
115 return 0;
116
117 ++WidthPos;
118 assert(*WidthPos == ':' &&
119 "Vector width specifier must be followed by a ':'");
120 ++WidthPos;
121
122 char *EndPos;
123 unsigned Width = ::strtol(WidthPos, &EndPos, 10);
124 assert(*EndPos == ':' && "Vector width specific must end with a ':'");
125 return Width;
126 }
127
isLike(unsigned ID,unsigned & FormatIdx,bool & HasVAListArg,const char * Fmt) const128 bool Builtin::Context::isLike(unsigned ID, unsigned &FormatIdx,
129 bool &HasVAListArg, const char *Fmt) const {
130 assert(Fmt && "Not passed a format string");
131 assert(::strlen(Fmt) == 2 &&
132 "Format string needs to be two characters long");
133 assert(::toupper(Fmt[0]) == Fmt[1] &&
134 "Format string is not in the form \"xX\"");
135
136 const char *Like = ::strpbrk(getRecord(ID).Attributes, Fmt);
137 if (!Like)
138 return false;
139
140 HasVAListArg = (*Like == Fmt[1]);
141
142 ++Like;
143 assert(*Like == ':' && "Format specifier must be followed by a ':'");
144 ++Like;
145
146 assert(::strchr(Like, ':') && "Format specifier must end with a ':'");
147 FormatIdx = ::strtol(Like, nullptr, 10);
148 return true;
149 }
150
isPrintfLike(unsigned ID,unsigned & FormatIdx,bool & HasVAListArg)151 bool Builtin::Context::isPrintfLike(unsigned ID, unsigned &FormatIdx,
152 bool &HasVAListArg) {
153 return isLike(ID, FormatIdx, HasVAListArg, "pP");
154 }
155
isScanfLike(unsigned ID,unsigned & FormatIdx,bool & HasVAListArg)156 bool Builtin::Context::isScanfLike(unsigned ID, unsigned &FormatIdx,
157 bool &HasVAListArg) {
158 return isLike(ID, FormatIdx, HasVAListArg, "sS");
159 }
160
performsCallback(unsigned ID,SmallVectorImpl<int> & Encoding) const161 bool Builtin::Context::performsCallback(unsigned ID,
162 SmallVectorImpl<int> &Encoding) const {
163 const char *CalleePos = ::strchr(getRecord(ID).Attributes, 'C');
164 if (!CalleePos)
165 return false;
166
167 ++CalleePos;
168 assert(*CalleePos == '<' &&
169 "Callback callee specifier must be followed by a '<'");
170 ++CalleePos;
171
172 char *EndPos;
173 int CalleeIdx = ::strtol(CalleePos, &EndPos, 10);
174 assert(CalleeIdx >= 0 && "Callee index is supposed to be positive!");
175 Encoding.push_back(CalleeIdx);
176
177 while (*EndPos == ',') {
178 const char *PayloadPos = EndPos + 1;
179
180 int PayloadIdx = ::strtol(PayloadPos, &EndPos, 10);
181 Encoding.push_back(PayloadIdx);
182 }
183
184 assert(*EndPos == '>' && "Callback callee specifier must end with a '>'");
185 return true;
186 }
187
canBeRedeclared(unsigned ID) const188 bool Builtin::Context::canBeRedeclared(unsigned ID) const {
189 return ID == Builtin::NotBuiltin ||
190 ID == Builtin::BI__va_start ||
191 (!hasReferenceArgsOrResult(ID) &&
192 !hasCustomTypechecking(ID));
193 }
194