clang  11.0.0git
Builtins.cpp
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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"
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 
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.
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 
109  Table.get(getRecord(ID).Name).setBuiltinID(0);
110 }
111 
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 
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 }
bool hasReferenceArgsOrResult(unsigned ID) const
Return true if this builtin has a result or any arguments which are reference types.
Definition: Builtins.h:169
bool isNoBuiltinFunc(StringRef Name) const
Is this a libc/libm function that is no longer recognized as a builtin because a -fno-builtin-* optio...
Definition: LangOptions.cpp:39
const char * Attributes
Definition: Builtins.h:54
static const Builtin::Info BuiltinInfo[]
Definition: Builtins.cpp:20
void forgetBuiltin(unsigned ID, IdentifierTable &Table)
Completely forget that the given ID was ever considered a builtin, e.g., because the user provided a ...
Definition: Builtins.cpp:108
bool isPrintfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg)
Determine whether this builtin is like printf in its formatting rules and, if so, set the index to th...
Definition: Builtins.cpp:151
const char * Name
Definition: Builtins.h:54
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:54
unsigned getAuxBuiltinID(unsigned ID) const
Return real builtin ID (i.e.
Definition: Builtins.h:221
bool performsCallback(unsigned ID, llvm::SmallVectorImpl< int > &Encoding) const
Determine whether this builtin has callback behavior (see llvm::AbstractCallSites for details)...
Definition: Builtins.cpp:161
LanguageID Langs
Definition: Builtins.h:55
unsigned getRequiredVectorWidth(unsigned ID) const
Definition: Builtins.cpp:112
Exposes information about the current target.
Definition: TargetInfo.h:179
Defines the clang::LangOptions interface.
Implements an efficient mapping from strings to IdentifierInfo nodes.
bool canBeRedeclared(unsigned ID) const
Returns true if this is a builtin that can be redeclared.
Definition: Builtins.cpp:188
Defines the clang::IdentifierInfo, clang::IdentifierTable, and clang::Selector interfaces.
const char * HeaderName
Definition: Builtins.h:54
bool isAuxBuiltinID(unsigned ID) const
Return true if builtin ID belongs to AuxTarget.
Definition: Builtins.h:215
IdentifierInfo & get(StringRef Name)
Return the identifier token info for the specified named identifier.
void initializeBuiltins(IdentifierTable &Table, const LangOptions &LangOpts)
Mark the identifiers for all the builtins with their appropriate builtin ID # and mark any non-portab...
Definition: Builtins.cpp:89
virtual ArrayRef< Builtin::Info > getTargetBuiltins() const =0
Return information about target-specific builtins for the current primary target, and info about whic...
bool isScanfLike(unsigned ID, unsigned &FormatIdx, bool &HasVAListArg)
Determine whether this builtin is like scanf in its formatting rules and, if so, set the index to the...
Definition: Builtins.cpp:156
static bool isBuiltinFunc(llvm::StringRef Name)
Returns true if this is a libc/libm function without the &#39;__builtin_&#39; prefix.
Definition: Builtins.cpp:50
Dataflow Directional Tag Classes.
void setBuiltinID(unsigned ID)
Defines the clang::TargetInfo interface.
bool hasCustomTypechecking(unsigned ID) const
Determines whether this builtin has custom typechecking.
Definition: Builtins.h:157
void InitializeTarget(const TargetInfo &Target, const TargetInfo *AuxTarget)
Perform target-specific initialization.
Definition: Builtins.cpp:42
Defines enum values for all the target-independent builtin functions.