clang  8.0.0svn
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, saw_fixed_point_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 isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
73  bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
74 
75  bool isFixedPointLiteral() const { return saw_fixed_point_suffix; }
76 
77  bool isIntegerLiteral() const {
78  return !saw_period && !saw_exponent && !isFixedPointLiteral();
79  }
80  bool isFloatingLiteral() const {
81  return (saw_period || saw_exponent) && !isFixedPointLiteral();
82  }
83 
84  bool hasUDSuffix() const {
85  return saw_ud_suffix;
86  }
87  StringRef getUDSuffix() const {
88  assert(saw_ud_suffix);
89  return UDSuffixBuf;
90  }
91  unsigned getUDSuffixOffset() const {
92  assert(saw_ud_suffix);
93  return SuffixBegin - ThisTokBegin;
94  }
95 
96  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
97 
98  unsigned getRadix() const { return radix; }
99 
100  /// GetIntegerValue - Convert this numeric literal value to an APInt that
101  /// matches Val's input width. If there is an overflow (i.e., if the unsigned
102  /// value read is larger than the APInt's bits will hold), set Val to the low
103  /// bits of the result and return true. Otherwise, return false.
104  bool GetIntegerValue(llvm::APInt &Val);
105 
106  /// GetFloatValue - Convert this numeric literal to a floating value, using
107  /// the specified APFloat fltSemantics (specifying float, double, etc).
108  /// The optional bool isExact (passed-by-reference) has its value
109  /// set to true if the returned APFloat can represent the number in the
110  /// literal exactly, and false otherwise.
111  llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
112 
113  /// GetFixedPointValue - Convert this numeric literal value into a
114  /// scaled integer that represents this value. Returns true if an overflow
115  /// occurred when calculating the integral part of the scaled integer or
116  /// calculating the digit sequence of the exponent.
117  bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale);
118 
119 private:
120 
121  void ParseNumberStartingWithZero(SourceLocation TokLoc);
122  void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
123 
124  static bool isDigitSeparator(char C) { return C == '\''; }
125 
126  /// Determine whether the sequence of characters [Start, End) contains
127  /// any real digits (not digit separators).
128  bool containsDigits(const char *Start, const char *End) {
129  return Start != End && (Start + 1 != End || !isDigitSeparator(Start[0]));
130  }
131 
132  enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
133 
134  /// Ensure that we don't have a digit separator here.
135  void checkSeparator(SourceLocation TokLoc, const char *Pos,
136  CheckSeparatorKind IsAfterDigits);
137 
138  /// SkipHexDigits - Read and skip over any hex digits, up to End.
139  /// Return a pointer to the first non-hex digit or End.
140  const char *SkipHexDigits(const char *ptr) {
141  while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
142  ptr++;
143  return ptr;
144  }
145 
146  /// SkipOctalDigits - Read and skip over any octal digits, up to End.
147  /// Return a pointer to the first non-hex digit or End.
148  const char *SkipOctalDigits(const char *ptr) {
149  while (ptr != ThisTokEnd &&
150  ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
151  ptr++;
152  return ptr;
153  }
154 
155  /// SkipDigits - Read and skip over any digits, up to End.
156  /// Return a pointer to the first non-hex digit or End.
157  const char *SkipDigits(const char *ptr) {
158  while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
159  ptr++;
160  return ptr;
161  }
162 
163  /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
164  /// Return a pointer to the first non-binary digit or End.
165  const char *SkipBinaryDigits(const char *ptr) {
166  while (ptr != ThisTokEnd &&
167  (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
168  ptr++;
169  return ptr;
170  }
171 
172 };
173 
174 /// CharLiteralParser - Perform interpretation and semantic analysis of a
175 /// character literal.
177  uint64_t Value;
179  bool IsMultiChar;
180  bool HadError;
181  SmallString<32> UDSuffixBuf;
182  unsigned UDSuffixOffset;
183 public:
184  CharLiteralParser(const char *begin, const char *end,
185  SourceLocation Loc, Preprocessor &PP,
187 
188  bool hadError() const { return HadError; }
189  bool isAscii() const { return Kind == tok::char_constant; }
190  bool isWide() const { return Kind == tok::wide_char_constant; }
191  bool isUTF8() const { return Kind == tok::utf8_char_constant; }
192  bool isUTF16() const { return Kind == tok::utf16_char_constant; }
193  bool isUTF32() const { return Kind == tok::utf32_char_constant; }
194  bool isMultiChar() const { return IsMultiChar; }
195  uint64_t getValue() const { return Value; }
196  StringRef getUDSuffix() const { return UDSuffixBuf; }
197  unsigned getUDSuffixOffset() const {
198  assert(!UDSuffixBuf.empty() && "no ud-suffix");
199  return UDSuffixOffset;
200  }
201 };
202 
203 /// StringLiteralParser - This decodes string escape characters and performs
204 /// wide string analysis and Translation Phase #6 (concatenation of string
205 /// literals) (C99 5.1.1.2p1).
207  const SourceManager &SM;
208  const LangOptions &Features;
209  const TargetInfo &Target;
210  DiagnosticsEngine *Diags;
211 
212  unsigned MaxTokenLength;
213  unsigned SizeBound;
214  unsigned CharByteWidth;
216  SmallString<512> ResultBuf;
217  char *ResultPtr; // cursor
218  SmallString<32> UDSuffixBuf;
219  unsigned UDSuffixToken;
220  unsigned UDSuffixOffset;
221 public:
223  Preprocessor &PP, bool Complain = true);
225  const SourceManager &sm, const LangOptions &features,
226  const TargetInfo &target,
227  DiagnosticsEngine *diags = nullptr)
228  : SM(sm), Features(features), Target(target), Diags(diags),
229  MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
230  ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
231  init(StringToks);
232  }
233 
234 
235  bool hadError;
236  bool Pascal;
237 
238  StringRef GetString() const {
239  return StringRef(ResultBuf.data(), GetStringLength());
240  }
241  unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
242 
243  unsigned GetNumStringChars() const {
244  return GetStringLength() / CharByteWidth;
245  }
246  /// getOffsetOfStringByte - This function returns the offset of the
247  /// specified byte of the string data represented by Token. This handles
248  /// advancing over escape sequences in the string.
249  ///
250  /// If the Diagnostics pointer is non-null, then this will do semantic
251  /// checking of the string literal and emit errors and warnings.
252  unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
253 
254  bool isAscii() const { return Kind == tok::string_literal; }
255  bool isWide() const { return Kind == tok::wide_string_literal; }
256  bool isUTF8() const { return Kind == tok::utf8_string_literal; }
257  bool isUTF16() const { return Kind == tok::utf16_string_literal; }
258  bool isUTF32() const { return Kind == tok::utf32_string_literal; }
259  bool isPascal() const { return Pascal; }
260 
261  StringRef getUDSuffix() const { return UDSuffixBuf; }
262 
263  /// Get the index of a token containing a ud-suffix.
264  unsigned getUDSuffixToken() const {
265  assert(!UDSuffixBuf.empty() && "no ud-suffix");
266  return UDSuffixToken;
267  }
268  /// Get the spelling offset of the first byte of the ud-suffix.
269  unsigned getUDSuffixOffset() const {
270  assert(!UDSuffixBuf.empty() && "no ud-suffix");
271  return UDSuffixOffset;
272  }
273 
274  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
275 
276 private:
277  void init(ArrayRef<Token> StringToks);
278  bool CopyStringFragment(const Token &Tok, const char *TokBegin,
279  StringRef Fragment);
280  void DiagnoseLexingError(SourceLocation Loc);
281 };
282 
283 } // end namespace clang
284 
285 #endif
StringRef getUDSuffix() const
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:50
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:149
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:54
bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale)
GetFixedPointValue - Convert this numeric literal value into a scaled integer that represents this va...
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:1472
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.
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
StringRef getUDSuffix() const
LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:94
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:127