clang  3.7.0
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/SmallString.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/Support/DataTypes.h"
25 
26 namespace clang {
27 
28 class DiagnosticsEngine;
29 class Preprocessor;
30 class Token;
31 class SourceLocation;
32 class TargetInfo;
33 class SourceManager;
34 class LangOptions;
35 
36 /// Copy characters from Input to Buf, expanding any UCNs.
37 void expandUCNs(SmallVectorImpl<char> &Buf, StringRef Input);
38 
39 /// NumericLiteralParser - This performs strict semantic analysis of the content
40 /// of a ppnumber, classifying it as either integer, floating, or erroneous,
41 /// determines the radix of the value and can convert it to a useful value.
43  Preprocessor &PP; // needed for diagnostics
44 
45  const char *const ThisTokBegin;
46  const char *const ThisTokEnd;
47  const char *DigitsBegin, *SuffixBegin; // markers
48  const char *s; // cursor
49 
50  unsigned radix;
51 
52  bool saw_exponent, saw_period, saw_ud_suffix;
53 
54  SmallString<32> UDSuffixBuf;
55 
56 public:
57  NumericLiteralParser(StringRef TokSpelling,
58  SourceLocation TokLoc,
59  Preprocessor &PP);
60  bool hadError : 1;
61  bool isUnsigned : 1;
62  bool isLong : 1; // This is *not* set for long long.
63  bool isLongLong : 1;
64  bool isFloat : 1; // 1.0f
65  bool isImaginary : 1; // 1.0i
66  uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
67 
68  bool isIntegerLiteral() const {
69  return !saw_period && !saw_exponent;
70  }
71  bool isFloatingLiteral() const {
72  return saw_period || saw_exponent;
73  }
74 
75  bool hasUDSuffix() const {
76  return saw_ud_suffix;
77  }
78  StringRef getUDSuffix() const {
79  assert(saw_ud_suffix);
80  return UDSuffixBuf;
81  }
82  unsigned getUDSuffixOffset() const {
83  assert(saw_ud_suffix);
84  return SuffixBegin - ThisTokBegin;
85  }
86 
87  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
88 
89  unsigned getRadix() const { return radix; }
90 
91  /// GetIntegerValue - Convert this numeric literal value to an APInt that
92  /// matches Val's input width. If there is an overflow (i.e., if the unsigned
93  /// value read is larger than the APInt's bits will hold), set Val to the low
94  /// bits of the result and return true. Otherwise, return false.
95  bool GetIntegerValue(llvm::APInt &Val);
96 
97  /// GetFloatValue - Convert this numeric literal to a floating value, using
98  /// the specified APFloat fltSemantics (specifying float, double, etc).
99  /// The optional bool isExact (passed-by-reference) has its value
100  /// set to true if the returned APFloat can represent the number in the
101  /// literal exactly, and false otherwise.
102  llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
103 
104 private:
105 
106  void ParseNumberStartingWithZero(SourceLocation TokLoc);
107 
108  static bool isDigitSeparator(char C) { return C == '\''; }
109 
110  enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
111 
112  /// \brief Ensure that we don't have a digit separator here.
113  void checkSeparator(SourceLocation TokLoc, const char *Pos,
114  CheckSeparatorKind IsAfterDigits);
115 
116  /// SkipHexDigits - Read and skip over any hex digits, up to End.
117  /// Return a pointer to the first non-hex digit or End.
118  const char *SkipHexDigits(const char *ptr) {
119  while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
120  ptr++;
121  return ptr;
122  }
123 
124  /// SkipOctalDigits - Read and skip over any octal digits, up to End.
125  /// Return a pointer to the first non-hex digit or End.
126  const char *SkipOctalDigits(const char *ptr) {
127  while (ptr != ThisTokEnd &&
128  ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
129  ptr++;
130  return ptr;
131  }
132 
133  /// SkipDigits - Read and skip over any digits, up to End.
134  /// Return a pointer to the first non-hex digit or End.
135  const char *SkipDigits(const char *ptr) {
136  while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
137  ptr++;
138  return ptr;
139  }
140 
141  /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
142  /// Return a pointer to the first non-binary digit or End.
143  const char *SkipBinaryDigits(const char *ptr) {
144  while (ptr != ThisTokEnd &&
145  (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
146  ptr++;
147  return ptr;
148  }
149 
150 };
151 
152 /// CharLiteralParser - Perform interpretation and semantic analysis of a
153 /// character literal.
155  uint64_t Value;
157  bool IsMultiChar;
158  bool HadError;
159  SmallString<32> UDSuffixBuf;
160  unsigned UDSuffixOffset;
161 public:
162  CharLiteralParser(const char *begin, const char *end,
163  SourceLocation Loc, Preprocessor &PP,
165 
166  bool hadError() const { return HadError; }
167  bool isAscii() const { return Kind == tok::char_constant; }
168  bool isWide() const { return Kind == tok::wide_char_constant; }
169  bool isUTF16() const { return Kind == tok::utf16_char_constant; }
170  bool isUTF32() const { return Kind == tok::utf32_char_constant; }
171  bool isMultiChar() const { return IsMultiChar; }
172  uint64_t getValue() const { return Value; }
173  StringRef getUDSuffix() const { return UDSuffixBuf; }
174  unsigned getUDSuffixOffset() const {
175  assert(!UDSuffixBuf.empty() && "no ud-suffix");
176  return UDSuffixOffset;
177  }
178 };
179 
180 /// StringLiteralParser - This decodes string escape characters and performs
181 /// wide string analysis and Translation Phase #6 (concatenation of string
182 /// literals) (C99 5.1.1.2p1).
184  const SourceManager &SM;
185  const LangOptions &Features;
186  const TargetInfo &Target;
187  DiagnosticsEngine *Diags;
188 
189  unsigned MaxTokenLength;
190  unsigned SizeBound;
191  unsigned CharByteWidth;
193  SmallString<512> ResultBuf;
194  char *ResultPtr; // cursor
195  SmallString<32> UDSuffixBuf;
196  unsigned UDSuffixToken;
197  unsigned UDSuffixOffset;
198 public:
200  Preprocessor &PP, bool Complain = true);
202  const SourceManager &sm, const LangOptions &features,
203  const TargetInfo &target,
204  DiagnosticsEngine *diags = nullptr)
205  : SM(sm), Features(features), Target(target), Diags(diags),
206  MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
207  ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
208  init(StringToks);
209  }
210 
211 
212  bool hadError;
213  bool Pascal;
214 
215  StringRef GetString() const {
216  return StringRef(ResultBuf.data(), GetStringLength());
217  }
218  unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
219 
220  unsigned GetNumStringChars() const {
221  return GetStringLength() / CharByteWidth;
222  }
223  /// getOffsetOfStringByte - This function returns the offset of the
224  /// specified byte of the string data represented by Token. This handles
225  /// advancing over escape sequences in the string.
226  ///
227  /// If the Diagnostics pointer is non-null, then this will do semantic
228  /// checking of the string literal and emit errors and warnings.
229  unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
230 
231  bool isAscii() const { return Kind == tok::string_literal; }
232  bool isWide() const { return Kind == tok::wide_string_literal; }
233  bool isUTF8() const { return Kind == tok::utf8_string_literal; }
234  bool isUTF16() const { return Kind == tok::utf16_string_literal; }
235  bool isUTF32() const { return Kind == tok::utf32_string_literal; }
236  bool isPascal() const { return Pascal; }
237 
238  StringRef getUDSuffix() const { return UDSuffixBuf; }
239 
240  /// Get the index of a token containing a ud-suffix.
241  unsigned getUDSuffixToken() const {
242  assert(!UDSuffixBuf.empty() && "no ud-suffix");
243  return UDSuffixToken;
244  }
245  /// Get the spelling offset of the first byte of the ud-suffix.
246  unsigned getUDSuffixOffset() const {
247  assert(!UDSuffixBuf.empty() && "no ud-suffix");
248  return UDSuffixOffset;
249  }
250 
251 private:
252  void init(ArrayRef<Token> StringToks);
253  bool CopyStringFragment(const Token &Tok, const char *TokBegin,
254  StringRef Fragment);
255  void DiagnoseLexingError(SourceLocation Loc);
256 };
257 
258 } // end namespace clang
259 
260 #endif
static LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:94
StringLiteralParser(ArrayRef< Token > StringToks, Preprocessor &PP, bool Complain=true)
unsigned getRadix() const
StringRef getUDSuffix() const
unsigned getUDSuffixToken() const
Get the index of a token containing a ud-suffix.
unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const
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)
uint64_t getValue() const
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:135
static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix)
NumericLiteralParser(StringRef TokSpelling, SourceLocation TokLoc, Preprocessor &PP)
Exposes information about the current target.
CharLiteralParser(const char *begin, const char *end, SourceLocation Loc, Preprocessor &PP, tok::TokenKind kind)
FormatToken * Token
StringRef getUDSuffix() const
The result type of a method or function.
bool GetIntegerValue(llvm::APInt &Val)
#define false
Definition: stdbool.h:33
Kind
Encodes a location in the source. The SourceManager can decode this to get at the full include stack...
llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result)
StringRef GetString() const
StringRef getUDSuffix() const
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.
unsigned getUDSuffixOffset() const
Get the spelling offset of the first byte of the ud-suffix.
unsigned getUDSuffixOffset() const
Defines the clang::TokenKind enum and support functions.
unsigned kind
All of the diagnostics that can be emitted by the frontend.
Definition: DiagnosticIDs.h:43
const StringRef Input
unsigned GetStringLength() const
unsigned getUDSuffixOffset() const
unsigned GetNumStringChars() 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:96
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