clang  6.0.0svn
LiteralSupport.h
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1 //===--- LiteralSupport.h ---------------------------------------*- C++ -*-===//
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 defines the NumericLiteralParser, CharLiteralParser, and
11 // StringLiteralParser interfaces.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_LEX_LITERALSUPPORT_H
16 #define LLVM_CLANG_LEX_LITERALSUPPORT_H
17 
18 #include "clang/Basic/CharInfo.h"
19 #include "clang/Basic/LLVM.h"
20 #include "clang/Basic/TokenKinds.h"
21 #include "llvm/ADT/APFloat.h"
22 #include "llvm/ADT/ArrayRef.h"
23 #include "llvm/ADT/SmallString.h"
24 #include "llvm/ADT/StringRef.h"
25 #include "llvm/Support/DataTypes.h"
26 
27 namespace clang {
28 
29 class DiagnosticsEngine;
30 class Preprocessor;
31 class Token;
32 class SourceLocation;
33 class TargetInfo;
34 class SourceManager;
35 class LangOptions;
36 
37 /// Copy characters from Input to Buf, expanding any UCNs.
38 void expandUCNs(SmallVectorImpl<char> &Buf, StringRef Input);
39 
40 /// NumericLiteralParser - This performs strict semantic analysis of the content
41 /// of a ppnumber, classifying it as either integer, floating, or erroneous,
42 /// determines the radix of the value and can convert it to a useful value.
44  Preprocessor &PP; // needed for diagnostics
45 
46  const char *const ThisTokBegin;
47  const char *const ThisTokEnd;
48  const char *DigitsBegin, *SuffixBegin; // markers
49  const char *s; // cursor
50 
51  unsigned radix;
52 
53  bool saw_exponent, saw_period, saw_ud_suffix;
54 
55  SmallString<32> UDSuffixBuf;
56 
57 public:
58  NumericLiteralParser(StringRef TokSpelling,
59  SourceLocation TokLoc,
60  Preprocessor &PP);
61  bool hadError : 1;
62  bool isUnsigned : 1;
63  bool isLong : 1; // This is *not* set for long long.
64  bool isLongLong : 1;
65  bool isHalf : 1; // 1.0h
66  bool isFloat : 1; // 1.0f
67  bool isImaginary : 1; // 1.0i
68  bool isFloat16 : 1; // 1.0f16
69  bool isFloat128 : 1; // 1.0q
70  uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
71 
72  bool isIntegerLiteral() const {
73  return !saw_period && !saw_exponent;
74  }
75  bool isFloatingLiteral() const {
76  return saw_period || saw_exponent;
77  }
78 
79  bool hasUDSuffix() const {
80  return saw_ud_suffix;
81  }
82  StringRef getUDSuffix() const {
83  assert(saw_ud_suffix);
84  return UDSuffixBuf;
85  }
86  unsigned getUDSuffixOffset() const {
87  assert(saw_ud_suffix);
88  return SuffixBegin - ThisTokBegin;
89  }
90 
91  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
92 
93  unsigned getRadix() const { return radix; }
94 
95  /// GetIntegerValue - Convert this numeric literal value to an APInt that
96  /// matches Val's input width. If there is an overflow (i.e., if the unsigned
97  /// value read is larger than the APInt's bits will hold), set Val to the low
98  /// bits of the result and return true. Otherwise, return false.
99  bool GetIntegerValue(llvm::APInt &Val);
100 
101  /// GetFloatValue - Convert this numeric literal to a floating value, using
102  /// the specified APFloat fltSemantics (specifying float, double, etc).
103  /// The optional bool isExact (passed-by-reference) has its value
104  /// set to true if the returned APFloat can represent the number in the
105  /// literal exactly, and false otherwise.
106  llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
107 
108 private:
109 
110  void ParseNumberStartingWithZero(SourceLocation TokLoc);
111  void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
112 
113  static bool isDigitSeparator(char C) { return C == '\''; }
114 
115  /// \brief Determine whether the sequence of characters [Start, End) contains
116  /// any real digits (not digit separators).
117  bool containsDigits(const char *Start, const char *End) {
118  return Start != End && (Start + 1 != End || !isDigitSeparator(Start[0]));
119  }
120 
121  enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
122 
123  /// \brief Ensure that we don't have a digit separator here.
124  void checkSeparator(SourceLocation TokLoc, const char *Pos,
125  CheckSeparatorKind IsAfterDigits);
126 
127  /// SkipHexDigits - Read and skip over any hex digits, up to End.
128  /// Return a pointer to the first non-hex digit or End.
129  const char *SkipHexDigits(const char *ptr) {
130  while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
131  ptr++;
132  return ptr;
133  }
134 
135  /// SkipOctalDigits - Read and skip over any octal digits, up to End.
136  /// Return a pointer to the first non-hex digit or End.
137  const char *SkipOctalDigits(const char *ptr) {
138  while (ptr != ThisTokEnd &&
139  ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
140  ptr++;
141  return ptr;
142  }
143 
144  /// SkipDigits - Read and skip over any digits, up to End.
145  /// Return a pointer to the first non-hex digit or End.
146  const char *SkipDigits(const char *ptr) {
147  while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
148  ptr++;
149  return ptr;
150  }
151 
152  /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
153  /// Return a pointer to the first non-binary digit or End.
154  const char *SkipBinaryDigits(const char *ptr) {
155  while (ptr != ThisTokEnd &&
156  (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
157  ptr++;
158  return ptr;
159  }
160 
161 };
162 
163 /// CharLiteralParser - Perform interpretation and semantic analysis of a
164 /// character literal.
166  uint64_t Value;
168  bool IsMultiChar;
169  bool HadError;
170  SmallString<32> UDSuffixBuf;
171  unsigned UDSuffixOffset;
172 public:
173  CharLiteralParser(const char *begin, const char *end,
174  SourceLocation Loc, Preprocessor &PP,
176 
177  bool hadError() const { return HadError; }
178  bool isAscii() const { return Kind == tok::char_constant; }
179  bool isWide() const { return Kind == tok::wide_char_constant; }
180  bool isUTF8() const { return Kind == tok::utf8_char_constant; }
181  bool isUTF16() const { return Kind == tok::utf16_char_constant; }
182  bool isUTF32() const { return Kind == tok::utf32_char_constant; }
183  bool isMultiChar() const { return IsMultiChar; }
184  uint64_t getValue() const { return Value; }
185  StringRef getUDSuffix() const { return UDSuffixBuf; }
186  unsigned getUDSuffixOffset() const {
187  assert(!UDSuffixBuf.empty() && "no ud-suffix");
188  return UDSuffixOffset;
189  }
190 };
191 
192 /// StringLiteralParser - This decodes string escape characters and performs
193 /// wide string analysis and Translation Phase #6 (concatenation of string
194 /// literals) (C99 5.1.1.2p1).
196  const SourceManager &SM;
197  const LangOptions &Features;
198  const TargetInfo &Target;
199  DiagnosticsEngine *Diags;
200 
201  unsigned MaxTokenLength;
202  unsigned SizeBound;
203  unsigned CharByteWidth;
205  SmallString<512> ResultBuf;
206  char *ResultPtr; // cursor
207  SmallString<32> UDSuffixBuf;
208  unsigned UDSuffixToken;
209  unsigned UDSuffixOffset;
210 public:
212  Preprocessor &PP, bool Complain = true);
214  const SourceManager &sm, const LangOptions &features,
215  const TargetInfo &target,
216  DiagnosticsEngine *diags = nullptr)
217  : SM(sm), Features(features), Target(target), Diags(diags),
218  MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
219  ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
220  init(StringToks);
221  }
222 
223 
224  bool hadError;
225  bool Pascal;
226 
227  StringRef GetString() const {
228  return StringRef(ResultBuf.data(), GetStringLength());
229  }
230  unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
231 
232  unsigned GetNumStringChars() const {
233  return GetStringLength() / CharByteWidth;
234  }
235  /// getOffsetOfStringByte - This function returns the offset of the
236  /// specified byte of the string data represented by Token. This handles
237  /// advancing over escape sequences in the string.
238  ///
239  /// If the Diagnostics pointer is non-null, then this will do semantic
240  /// checking of the string literal and emit errors and warnings.
241  unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
242 
243  bool isAscii() const { return Kind == tok::string_literal; }
244  bool isWide() const { return Kind == tok::wide_string_literal; }
245  bool isUTF8() const { return Kind == tok::utf8_string_literal; }
246  bool isUTF16() const { return Kind == tok::utf16_string_literal; }
247  bool isUTF32() const { return Kind == tok::utf32_string_literal; }
248  bool isPascal() const { return Pascal; }
249 
250  StringRef getUDSuffix() const { return UDSuffixBuf; }
251 
252  /// Get the index of a token containing a ud-suffix.
253  unsigned getUDSuffixToken() const {
254  assert(!UDSuffixBuf.empty() && "no ud-suffix");
255  return UDSuffixToken;
256  }
257  /// Get the spelling offset of the first byte of the ud-suffix.
258  unsigned getUDSuffixOffset() const {
259  assert(!UDSuffixBuf.empty() && "no ud-suffix");
260  return UDSuffixOffset;
261  }
262 
263  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
264 
265 private:
266  void init(ArrayRef<Token> StringToks);
267  bool CopyStringFragment(const Token &Tok, const char *TokBegin,
268  StringRef Fragment);
269  void DiagnoseLexingError(SourceLocation Loc);
270 };
271 
272 } // end namespace clang
273 
274 #endif
StringRef getUDSuffix() const
static LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:94
unsigned GetNumStringChars() const
uint64_t getValue() const
unsigned GetStringLength() const
unsigned getUDSuffixOffset() const
Token - This structure provides full information about a lexed token.
Definition: Token.h:35
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:48
StringLiteralParser(ArrayRef< Token > StringToks, const SourceManager &sm, const LangOptions &features, const TargetInfo &target, DiagnosticsEngine *diags=nullptr)
const FormatToken & Tok
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:147
static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix)
Determine whether a suffix is a valid ud-suffix.
unsigned getUDSuffixOffset() const
NumericLiteralParser(StringRef TokSpelling, SourceLocation TokLoc, Preprocessor &PP)
integer-constant: [C99 6.4.4.1] decimal-constant integer-suffix octal-constant integer-suffix hexadec...
Exposes information about the current target.
Definition: TargetInfo.h:55
SourceLocation End
CharLiteralParser - Perform interpretation and semantic analysis of a character literal.
The result type of a method or function.
StringRef GetString() const
const SourceManager & SM
Definition: Format.cpp:1308
bool GetIntegerValue(llvm::APInt &Val)
GetIntegerValue - Convert this numeric literal value to an APInt that matches Val&#39;s input width...
unsigned getUDSuffixOffset() const
Get the spelling offset of the first byte of the ud-suffix.
#define false
Definition: stdbool.h:33
Kind
unsigned getUDSuffixToken() const
Get the index of a token containing a ud-suffix.
Encodes a location in the source.
llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result)
GetFloatValue - Convert this numeric literal to a floating value, using the specified APFloat fltSema...
TokenKind
Provides a simple uniform namespace for tokens from all C languages.
Definition: TokenKinds.h:25
void expandUCNs(SmallVectorImpl< char > &Buf, StringRef Input)
Copy characters from Input to Buf, expanding any UCNs.
Dataflow Directional Tag Classes.
StringRef getUDSuffix() const
Defines the clang::TokenKind enum and support functions.
StringLiteralParser - This decodes string escape characters and performs wide string analysis and Tra...
unsigned kind
All of the diagnostics that can be emitted by the frontend.
Definition: DiagnosticIDs.h:61
NumericLiteralParser - This performs strict semantic analysis of the content of a ppnumber...
StringRef getUDSuffix() const
This class handles loading and caching of source files into memory.
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:98
static LLVM_READONLY bool isHexDigit(unsigned char c)
Return true if this character is an ASCII hex digit: [0-9a-fA-F].
Definition: CharInfo.h:124