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 "BuiltinTargetFeatures.h"
15 #include "clang/Basic/IdentifierTable.h"
16 #include "clang/Basic/LangOptions.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include "llvm/ADT/StringRef.h"
19 using namespace clang;
20
21 static const Builtin::Info BuiltinInfo[] = {
22 { "not a builtin function", nullptr, nullptr, nullptr, ALL_LANGUAGES,nullptr},
23 #define BUILTIN(ID, TYPE, ATTRS) \
24 { #ID, TYPE, ATTRS, nullptr, ALL_LANGUAGES, nullptr },
25 #define LANGBUILTIN(ID, TYPE, ATTRS, LANGS) \
26 { #ID, TYPE, ATTRS, nullptr, LANGS, nullptr },
27 #define LIBBUILTIN(ID, TYPE, ATTRS, HEADER, LANGS) \
28 { #ID, TYPE, ATTRS, HEADER, LANGS, nullptr },
29 #include "clang/Basic/Builtins.def"
30 };
31
getRecord(unsigned ID) const32 const Builtin::Info &Builtin::Context::getRecord(unsigned ID) const {
33 if (ID < Builtin::FirstTSBuiltin)
34 return BuiltinInfo[ID];
35 assert(((ID - Builtin::FirstTSBuiltin) <
36 (TSRecords.size() + AuxTSRecords.size())) &&
37 "Invalid builtin ID!");
38 if (isAuxBuiltinID(ID))
39 return AuxTSRecords[getAuxBuiltinID(ID) - Builtin::FirstTSBuiltin];
40 return TSRecords[ID - Builtin::FirstTSBuiltin];
41 }
42
InitializeTarget(const TargetInfo & Target,const TargetInfo * AuxTarget)43 void Builtin::Context::InitializeTarget(const TargetInfo &Target,
44 const TargetInfo *AuxTarget) {
45 assert(TSRecords.empty() && "Already initialized target?");
46 TSRecords = Target.getTargetBuiltins();
47 if (AuxTarget)
48 AuxTSRecords = AuxTarget->getTargetBuiltins();
49 }
50
isBuiltinFunc(llvm::StringRef FuncName)51 bool Builtin::Context::isBuiltinFunc(llvm::StringRef FuncName) {
52 bool InStdNamespace = FuncName.consume_front("std-");
53 for (unsigned i = Builtin::NotBuiltin + 1; i != Builtin::FirstTSBuiltin;
54 ++i) {
55 if (FuncName.equals(BuiltinInfo[i].Name) &&
56 (bool)strchr(BuiltinInfo[i].Attributes, 'z') == InStdNamespace)
57 return strchr(BuiltinInfo[i].Attributes, 'f') != nullptr;
58 }
59
60 return false;
61 }
62
63 /// Is this builtin supported according to the given language options?
builtinIsSupported(const Builtin::Info & BuiltinInfo,const LangOptions & LangOpts)64 static bool builtinIsSupported(const Builtin::Info &BuiltinInfo,
65 const LangOptions &LangOpts) {
66 bool BuiltinsUnsupported =
67 LangOpts.NoBuiltin && strchr(BuiltinInfo.Attributes, 'f') != nullptr;
68 bool CorBuiltinsUnsupported =
69 !LangOpts.Coroutines && (BuiltinInfo.Langs & COR_LANG);
70 bool MathBuiltinsUnsupported =
71 LangOpts.NoMathBuiltin && BuiltinInfo.HeaderName &&
72 llvm::StringRef(BuiltinInfo.HeaderName).equals("math.h");
73 bool GnuModeUnsupported = !LangOpts.GNUMode && (BuiltinInfo.Langs & GNU_LANG);
74 bool MSModeUnsupported =
75 !LangOpts.MicrosoftExt && (BuiltinInfo.Langs & MS_LANG);
76 bool ObjCUnsupported = !LangOpts.ObjC && BuiltinInfo.Langs == OBJC_LANG;
77 bool OclCUnsupported =
78 !LangOpts.OpenCL && (BuiltinInfo.Langs & ALL_OCL_LANGUAGES);
79 bool OclGASUnsupported =
80 !LangOpts.OpenCLGenericAddressSpace && (BuiltinInfo.Langs & OCL_GAS);
81 bool OclPipeUnsupported =
82 !LangOpts.OpenCLPipes && (BuiltinInfo.Langs & OCL_PIPE);
83 // Device side enqueue is not supported until OpenCL 2.0. In 2.0 and higher
84 // support is indicated with language option for blocks.
85 bool OclDSEUnsupported =
86 (LangOpts.getOpenCLCompatibleVersion() < 200 || !LangOpts.Blocks) &&
87 (BuiltinInfo.Langs & OCL_DSE);
88 bool OpenMPUnsupported = !LangOpts.OpenMP && BuiltinInfo.Langs == OMP_LANG;
89 bool CUDAUnsupported = !LangOpts.CUDA && BuiltinInfo.Langs == CUDA_LANG;
90 bool CPlusPlusUnsupported =
91 !LangOpts.CPlusPlus && BuiltinInfo.Langs == CXX_LANG;
92 return !BuiltinsUnsupported && !CorBuiltinsUnsupported &&
93 !MathBuiltinsUnsupported && !OclCUnsupported && !OclGASUnsupported &&
94 !OclPipeUnsupported && !OclDSEUnsupported && !OpenMPUnsupported &&
95 !GnuModeUnsupported && !MSModeUnsupported && !ObjCUnsupported &&
96 !CPlusPlusUnsupported && !CUDAUnsupported;
97 }
98
99 /// initializeBuiltins - Mark the identifiers for all the builtins with their
100 /// appropriate builtin ID # and mark any non-portable builtin identifiers as
101 /// such.
initializeBuiltins(IdentifierTable & Table,const LangOptions & LangOpts)102 void Builtin::Context::initializeBuiltins(IdentifierTable &Table,
103 const LangOptions& LangOpts) {
104 // Step #1: mark all target-independent builtins with their ID's.
105 for (unsigned i = Builtin::NotBuiltin+1; i != Builtin::FirstTSBuiltin; ++i)
106 if (builtinIsSupported(BuiltinInfo[i], LangOpts)) {
107 Table.get(BuiltinInfo[i].Name).setBuiltinID(i);
108 }
109
110 // Step #2: Register target-specific builtins.
111 for (unsigned i = 0, e = TSRecords.size(); i != e; ++i)
112 if (builtinIsSupported(TSRecords[i], LangOpts))
113 Table.get(TSRecords[i].Name).setBuiltinID(i + Builtin::FirstTSBuiltin);
114
115 // Step #3: Register target-specific builtins for AuxTarget.
116 for (unsigned i = 0, e = AuxTSRecords.size(); i != e; ++i)
117 Table.get(AuxTSRecords[i].Name)
118 .setBuiltinID(i + Builtin::FirstTSBuiltin + TSRecords.size());
119
120 // Step #4: Unregister any builtins specified by -fno-builtin-foo.
121 for (llvm::StringRef Name : LangOpts.NoBuiltinFuncs) {
122 bool InStdNamespace = Name.consume_front("std-");
123 auto NameIt = Table.find(Name);
124 if (NameIt != Table.end()) {
125 unsigned ID = NameIt->second->getBuiltinID();
126 if (ID != Builtin::NotBuiltin && isPredefinedLibFunction(ID) &&
127 isInStdNamespace(ID) == InStdNamespace) {
128 Table.get(Name).setBuiltinID(Builtin::NotBuiltin);
129 }
130 }
131 }
132 }
133
getRequiredVectorWidth(unsigned ID) const134 unsigned Builtin::Context::getRequiredVectorWidth(unsigned ID) const {
135 const char *WidthPos = ::strchr(getRecord(ID).Attributes, 'V');
136 if (!WidthPos)
137 return 0;
138
139 ++WidthPos;
140 assert(*WidthPos == ':' &&
141 "Vector width specifier must be followed by a ':'");
142 ++WidthPos;
143
144 char *EndPos;
145 unsigned Width = ::strtol(WidthPos, &EndPos, 10);
146 assert(*EndPos == ':' && "Vector width specific must end with a ':'");
147 return Width;
148 }
149
isLike(unsigned ID,unsigned & FormatIdx,bool & HasVAListArg,const char * Fmt) const150 bool Builtin::Context::isLike(unsigned ID, unsigned &FormatIdx,
151 bool &HasVAListArg, const char *Fmt) const {
152 assert(Fmt && "Not passed a format string");
153 assert(::strlen(Fmt) == 2 &&
154 "Format string needs to be two characters long");
155 assert(::toupper(Fmt[0]) == Fmt[1] &&
156 "Format string is not in the form \"xX\"");
157
158 const char *Like = ::strpbrk(getRecord(ID).Attributes, Fmt);
159 if (!Like)
160 return false;
161
162 HasVAListArg = (*Like == Fmt[1]);
163
164 ++Like;
165 assert(*Like == ':' && "Format specifier must be followed by a ':'");
166 ++Like;
167
168 assert(::strchr(Like, ':') && "Format specifier must end with a ':'");
169 FormatIdx = ::strtol(Like, nullptr, 10);
170 return true;
171 }
172
isPrintfLike(unsigned ID,unsigned & FormatIdx,bool & HasVAListArg)173 bool Builtin::Context::isPrintfLike(unsigned ID, unsigned &FormatIdx,
174 bool &HasVAListArg) {
175 return isLike(ID, FormatIdx, HasVAListArg, "pP");
176 }
177
isScanfLike(unsigned ID,unsigned & FormatIdx,bool & HasVAListArg)178 bool Builtin::Context::isScanfLike(unsigned ID, unsigned &FormatIdx,
179 bool &HasVAListArg) {
180 return isLike(ID, FormatIdx, HasVAListArg, "sS");
181 }
182
performsCallback(unsigned ID,SmallVectorImpl<int> & Encoding) const183 bool Builtin::Context::performsCallback(unsigned ID,
184 SmallVectorImpl<int> &Encoding) const {
185 const char *CalleePos = ::strchr(getRecord(ID).Attributes, 'C');
186 if (!CalleePos)
187 return false;
188
189 ++CalleePos;
190 assert(*CalleePos == '<' &&
191 "Callback callee specifier must be followed by a '<'");
192 ++CalleePos;
193
194 char *EndPos;
195 int CalleeIdx = ::strtol(CalleePos, &EndPos, 10);
196 assert(CalleeIdx >= 0 && "Callee index is supposed to be positive!");
197 Encoding.push_back(CalleeIdx);
198
199 while (*EndPos == ',') {
200 const char *PayloadPos = EndPos + 1;
201
202 int PayloadIdx = ::strtol(PayloadPos, &EndPos, 10);
203 Encoding.push_back(PayloadIdx);
204 }
205
206 assert(*EndPos == '>' && "Callback callee specifier must end with a '>'");
207 return true;
208 }
209
canBeRedeclared(unsigned ID) const210 bool Builtin::Context::canBeRedeclared(unsigned ID) const {
211 return ID == Builtin::NotBuiltin || ID == Builtin::BI__va_start ||
212 (!hasReferenceArgsOrResult(ID) && !hasCustomTypechecking(ID)) ||
213 isInStdNamespace(ID);
214 }
215
evaluateRequiredTargetFeatures(StringRef RequiredFeatures,const llvm::StringMap<bool> & TargetFetureMap)216 bool Builtin::evaluateRequiredTargetFeatures(
217 StringRef RequiredFeatures, const llvm::StringMap<bool> &TargetFetureMap) {
218 // Return true if the builtin doesn't have any required features.
219 if (RequiredFeatures.empty())
220 return true;
221 assert(!RequiredFeatures.contains(' ') && "Space in feature list");
222
223 TargetFeatures TF(TargetFetureMap);
224 return TF.hasRequiredFeatures(RequiredFeatures);
225 }
226