xref: /freebsd/contrib/llvm-project/clang/lib/Basic/Builtins.cpp (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
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 
31 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 
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 
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 
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.
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 
108 void Builtin::Context::forgetBuiltin(unsigned ID, IdentifierTable &Table) {
109   Table.get(getRecord(ID).Name).setBuiltinID(0);
110 }
111 
112 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 
128 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 
151 bool Builtin::Context::isPrintfLike(unsigned ID, unsigned &FormatIdx,
152                                     bool &HasVAListArg) {
153   return isLike(ID, FormatIdx, HasVAListArg, "pP");
154 }
155 
156 bool Builtin::Context::isScanfLike(unsigned ID, unsigned &FormatIdx,
157                                    bool &HasVAListArg) {
158   return isLike(ID, FormatIdx, HasVAListArg, "sS");
159 }
160 
161 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 
188 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