clang  9.0.0svn
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(const char *Name) {
51  StringRef FuncName(Name);
52  for (unsigned i = Builtin::NotBuiltin + 1; i != Builtin::FirstTSBuiltin; ++i)
53  if (FuncName.equals(BuiltinInfo[i].Name))
54  return strchr(BuiltinInfo[i].Attributes, 'f') != nullptr;
55 
56  return false;
57 }
58 
59 bool Builtin::Context::builtinIsSupported(const Builtin::Info &BuiltinInfo,
60  const LangOptions &LangOpts) {
61  bool BuiltinsUnsupported =
62  (LangOpts.NoBuiltin || LangOpts.isNoBuiltinFunc(BuiltinInfo.Name)) &&
63  strchr(BuiltinInfo.Attributes, 'f');
64  bool MathBuiltinsUnsupported =
65  LangOpts.NoMathBuiltin && BuiltinInfo.HeaderName &&
66  llvm::StringRef(BuiltinInfo.HeaderName).equals("math.h");
67  bool GnuModeUnsupported = !LangOpts.GNUMode && (BuiltinInfo.Langs & GNU_LANG);
68  bool MSModeUnsupported =
69  !LangOpts.MicrosoftExt && (BuiltinInfo.Langs & MS_LANG);
70  bool ObjCUnsupported = !LangOpts.ObjC && BuiltinInfo.Langs == OBJC_LANG;
71  bool OclC1Unsupported = (LangOpts.OpenCLVersion / 100) != 1 &&
72  (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES ) == OCLC1X_LANG;
73  bool OclC2Unsupported = LangOpts.OpenCLVersion != 200 &&
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  return !BuiltinsUnsupported && !MathBuiltinsUnsupported && !OclCUnsupported &&
79  !OclC1Unsupported && !OclC2Unsupported && !OpenMPUnsupported &&
80  !GnuModeUnsupported && !MSModeUnsupported && !ObjCUnsupported;
81 }
82 
83 /// initializeBuiltins - Mark the identifiers for all the builtins with their
84 /// appropriate builtin ID # and mark any non-portable builtin identifiers as
85 /// such.
87  const LangOptions& LangOpts) {
88  // Step #1: mark all target-independent builtins with their ID's.
89  for (unsigned i = Builtin::NotBuiltin+1; i != Builtin::FirstTSBuiltin; ++i)
90  if (builtinIsSupported(BuiltinInfo[i], LangOpts)) {
91  Table.get(BuiltinInfo[i].Name).setBuiltinID(i);
92  }
93 
94  // Step #2: Register target-specific builtins.
95  for (unsigned i = 0, e = TSRecords.size(); i != e; ++i)
96  if (builtinIsSupported(TSRecords[i], LangOpts))
97  Table.get(TSRecords[i].Name).setBuiltinID(i + Builtin::FirstTSBuiltin);
98 
99  // Step #3: Register target-specific builtins for AuxTarget.
100  for (unsigned i = 0, e = AuxTSRecords.size(); i != e; ++i)
101  Table.get(AuxTSRecords[i].Name)
102  .setBuiltinID(i + Builtin::FirstTSBuiltin + TSRecords.size());
103 }
104 
106  Table.get(getRecord(ID).Name).setBuiltinID(0);
107 }
108 
110  const char *WidthPos = ::strchr(getRecord(ID).Attributes, 'V');
111  if (!WidthPos)
112  return 0;
113 
114  ++WidthPos;
115  assert(*WidthPos == ':' &&
116  "Vector width specifier must be followed by a ':'");
117  ++WidthPos;
118 
119  char *EndPos;
120  unsigned Width = ::strtol(WidthPos, &EndPos, 10);
121  assert(*EndPos == ':' && "Vector width specific must end with a ':'");
122  return Width;
123 }
124 
125 bool Builtin::Context::isLike(unsigned ID, unsigned &FormatIdx,
126  bool &HasVAListArg, const char *Fmt) const {
127  assert(Fmt && "Not passed a format string");
128  assert(::strlen(Fmt) == 2 &&
129  "Format string needs to be two characters long");
130  assert(::toupper(Fmt[0]) == Fmt[1] &&
131  "Format string is not in the form \"xX\"");
132 
133  const char *Like = ::strpbrk(getRecord(ID).Attributes, Fmt);
134  if (!Like)
135  return false;
136 
137  HasVAListArg = (*Like == Fmt[1]);
138 
139  ++Like;
140  assert(*Like == ':' && "Format specifier must be followed by a ':'");
141  ++Like;
142 
143  assert(::strchr(Like, ':') && "Format specifier must end with a ':'");
144  FormatIdx = ::strtol(Like, nullptr, 10);
145  return true;
146 }
147 
148 bool Builtin::Context::isPrintfLike(unsigned ID, unsigned &FormatIdx,
149  bool &HasVAListArg) {
150  return isLike(ID, FormatIdx, HasVAListArg, "pP");
151 }
152 
153 bool Builtin::Context::isScanfLike(unsigned ID, unsigned &FormatIdx,
154  bool &HasVAListArg) {
155  return isLike(ID, FormatIdx, HasVAListArg, "sS");
156 }
157 
160  const char *CalleePos = ::strchr(getRecord(ID).Attributes, 'C');
161  if (!CalleePos)
162  return false;
163 
164  ++CalleePos;
165  assert(*CalleePos == '<' &&
166  "Callback callee specifier must be followed by a '<'");
167  ++CalleePos;
168 
169  char *EndPos;
170  int CalleeIdx = ::strtol(CalleePos, &EndPos, 10);
171  assert(CalleeIdx >= 0 && "Callee index is supposed to be positive!");
172  Encoding.push_back(CalleeIdx);
173 
174  while (*EndPos == ',') {
175  const char *PayloadPos = EndPos + 1;
176 
177  int PayloadIdx = ::strtol(PayloadPos, &EndPos, 10);
178  Encoding.push_back(PayloadIdx);
179  }
180 
181  assert(*EndPos == '>' && "Callback callee specifier must end with a '>'");
182  return true;
183 }
184 
185 bool Builtin::Context::canBeRedeclared(unsigned ID) const {
186  return ID == Builtin::NotBuiltin ||
187  ID == Builtin::BI__va_start ||
188  (!hasReferenceArgsOrResult(ID) &&
189  !hasCustomTypechecking(ID));
190 }
bool hasReferenceArgsOrResult(unsigned ID) const
Return true if this builtin has a result or any arguments which are reference types.
Definition: Builtins.h:171
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:56
static const Builtin::Info BuiltinInfo[]
Definition: Builtins.cpp:20
static bool isBuiltinFunc(const char *Name)
Returns true if this is a libc/libm function without the &#39;__builtin_&#39; prefix.
Definition: Builtins.cpp:50
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:105
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:148
const char * Name
Definition: Builtins.h:56
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:49
unsigned getAuxBuiltinID(unsigned ID) const
Return real builtin ID (i.e.
Definition: Builtins.h:223
bool performsCallback(unsigned ID, llvm::SmallVectorImpl< int > &Encoding) const
Determine whether this builtin has callback behavior (see llvm::AbstractCallSites for details)...
Definition: Builtins.cpp:158
LanguageID Langs
Definition: Builtins.h:57
unsigned getRequiredVectorWidth(unsigned ID) const
Definition: Builtins.cpp:109
Exposes information about the current target.
Definition: TargetInfo.h:161
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:185
Defines the clang::IdentifierInfo, clang::IdentifierTable, and clang::Selector interfaces.
const char * HeaderName
Definition: Builtins.h:56
bool isAuxBuiltinID(unsigned ID) const
Return true if builtin ID belongs to AuxTarget.
Definition: Builtins.h:217
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:86
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:153
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:159
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.