1//===--- Builtins.cpp - Builtin function implementation -------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements various things for builtin functions.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Basic/Builtins.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"
19using namespace clang;
20
21static 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
32const 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
43void 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
51bool Builtin::Context::isBuiltinFunc(const char *Name) {
52  StringRef FuncName(Name);
53  for (unsigned i = Builtin::NotBuiltin + 1; i != Builtin::FirstTSBuiltin; ++i)
54    if (FuncName.equals(BuiltinInfo[i].Name))
55      return strchr(BuiltinInfo[i].Attributes, 'f') != nullptr;
56
57  return false;
58}
59
60bool Builtin::Context::builtinIsSupported(const Builtin::Info &BuiltinInfo,
61                                          const LangOptions &LangOpts) {
62  bool BuiltinsUnsupported =
63      (LangOpts.NoBuiltin || LangOpts.isNoBuiltinFunc(BuiltinInfo.Name)) &&
64      strchr(BuiltinInfo.Attributes, 'f');
65  bool MathBuiltinsUnsupported =
66    LangOpts.NoMathBuiltin && BuiltinInfo.HeaderName &&
67    llvm::StringRef(BuiltinInfo.HeaderName).equals("math.h");
68  bool GnuModeUnsupported = !LangOpts.GNUMode && (BuiltinInfo.Langs & GNU_LANG);
69  bool MSModeUnsupported =
70      !LangOpts.MicrosoftExt && (BuiltinInfo.Langs & MS_LANG);
71  bool ObjCUnsupported = !LangOpts.ObjC1 && BuiltinInfo.Langs == OBJC_LANG;
72  bool OclCUnsupported = LangOpts.OpenCLVersion != 200 &&
73                         BuiltinInfo.Langs == OCLC20_LANG;
74  return !BuiltinsUnsupported && !MathBuiltinsUnsupported && !OclCUnsupported &&
75         !GnuModeUnsupported && !MSModeUnsupported && !ObjCUnsupported;
76}
77
78/// initializeBuiltins - Mark the identifiers for all the builtins with their
79/// appropriate builtin ID # and mark any non-portable builtin identifiers as
80/// such.
81void Builtin::Context::initializeBuiltins(IdentifierTable &Table,
82                                          const LangOptions& LangOpts) {
83  // Step #1: mark all target-independent builtins with their ID's.
84  for (unsigned i = Builtin::NotBuiltin+1; i != Builtin::FirstTSBuiltin; ++i)
85    if (builtinIsSupported(BuiltinInfo[i], LangOpts)) {
86      Table.get(BuiltinInfo[i].Name).setBuiltinID(i);
87    }
88
89  // Step #2: Register target-specific builtins.
90  for (unsigned i = 0, e = TSRecords.size(); i != e; ++i)
91    if (builtinIsSupported(TSRecords[i], LangOpts))
92      Table.get(TSRecords[i].Name).setBuiltinID(i + Builtin::FirstTSBuiltin);
93
94  // Step #3: Register target-specific builtins for AuxTarget.
95  for (unsigned i = 0, e = AuxTSRecords.size(); i != e; ++i)
96    Table.get(AuxTSRecords[i].Name)
97        .setBuiltinID(i + Builtin::FirstTSBuiltin + TSRecords.size());
98}
99
100void Builtin::Context::forgetBuiltin(unsigned ID, IdentifierTable &Table) {
101  Table.get(getRecord(ID).Name).setBuiltinID(0);
102}
103
104bool Builtin::Context::isLike(unsigned ID, unsigned &FormatIdx,
105                              bool &HasVAListArg, const char *Fmt) const {
106  assert(Fmt && "Not passed a format string");
107  assert(::strlen(Fmt) == 2 &&
108         "Format string needs to be two characters long");
109  assert(::toupper(Fmt[0]) == Fmt[1] &&
110         "Format string is not in the form \"xX\"");
111
112  const char *Like = ::strpbrk(getRecord(ID).Attributes, Fmt);
113  if (!Like)
114    return false;
115
116  HasVAListArg = (*Like == Fmt[1]);
117
118  ++Like;
119  assert(*Like == ':' && "Format specifier must be followed by a ':'");
120  ++Like;
121
122  assert(::strchr(Like, ':') && "Format specifier must end with a ':'");
123  FormatIdx = ::strtol(Like, nullptr, 10);
124  return true;
125}
126
127bool Builtin::Context::isPrintfLike(unsigned ID, unsigned &FormatIdx,
128                                    bool &HasVAListArg) {
129  return isLike(ID, FormatIdx, HasVAListArg, "pP");
130}
131
132bool Builtin::Context::isScanfLike(unsigned ID, unsigned &FormatIdx,
133                                   bool &HasVAListArg) {
134  return isLike(ID, FormatIdx, HasVAListArg, "sS");
135}
136