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LiteralSupport.h
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1 //===--- LiteralSupport.h ---------------------------------------*- C++ -*-===//
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 defines the NumericLiteralParser, CharLiteralParser, and
10 // StringLiteralParser interfaces.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LEX_LITERALSUPPORT_H
15 #define LLVM_CLANG_LEX_LITERALSUPPORT_H
16 
17 #include "clang/Basic/CharInfo.h"
18 #include "clang/Basic/LLVM.h"
19 #include "clang/Basic/TokenKinds.h"
20 #include "llvm/ADT/APFloat.h"
21 #include "llvm/ADT/ArrayRef.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, saw_fixed_point_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 isHalf : 1; // 1.0h
65  bool isFloat : 1; // 1.0f
66  bool isImaginary : 1; // 1.0i
67  bool isFloat16 : 1; // 1.0f16
68  bool isFloat128 : 1; // 1.0q
69  uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
70 
71  bool isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
72  bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
73 
74  bool isFixedPointLiteral() const { return saw_fixed_point_suffix; }
75 
76  bool isIntegerLiteral() const {
77  return !saw_period && !saw_exponent && !isFixedPointLiteral();
78  }
79  bool isFloatingLiteral() const {
80  return (saw_period || saw_exponent) && !isFixedPointLiteral();
81  }
82 
83  bool hasUDSuffix() const {
84  return saw_ud_suffix;
85  }
86  StringRef getUDSuffix() const {
87  assert(saw_ud_suffix);
88  return UDSuffixBuf;
89  }
90  unsigned getUDSuffixOffset() const {
91  assert(saw_ud_suffix);
92  return SuffixBegin - ThisTokBegin;
93  }
94 
95  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
96 
97  unsigned getRadix() const { return radix; }
98 
99  /// GetIntegerValue - Convert this numeric literal value to an APInt that
100  /// matches Val's input width. If there is an overflow (i.e., if the unsigned
101  /// value read is larger than the APInt's bits will hold), set Val to the low
102  /// bits of the result and return true. Otherwise, return false.
103  bool GetIntegerValue(llvm::APInt &Val);
104 
105  /// GetFloatValue - Convert this numeric literal to a floating value, using
106  /// the specified APFloat fltSemantics (specifying float, double, etc).
107  /// The optional bool isExact (passed-by-reference) has its value
108  /// set to true if the returned APFloat can represent the number in the
109  /// literal exactly, and false otherwise.
110  llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
111 
112  /// GetFixedPointValue - Convert this numeric literal value into a
113  /// scaled integer that represents this value. Returns true if an overflow
114  /// occurred when calculating the integral part of the scaled integer or
115  /// calculating the digit sequence of the exponent.
116  bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale);
117 
118 private:
119 
120  void ParseNumberStartingWithZero(SourceLocation TokLoc);
121  void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
122 
123  static bool isDigitSeparator(char C) { return C == '\''; }
124 
125  /// Determine whether the sequence of characters [Start, End) contains
126  /// any real digits (not digit separators).
127  bool containsDigits(const char *Start, const char *End) {
128  return Start != End && (Start + 1 != End || !isDigitSeparator(Start[0]));
129  }
130 
131  enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
132 
133  /// Ensure that we don't have a digit separator here.
134  void checkSeparator(SourceLocation TokLoc, const char *Pos,
135  CheckSeparatorKind IsAfterDigits);
136 
137  /// SkipHexDigits - Read and skip over any hex digits, up to End.
138  /// Return a pointer to the first non-hex digit or End.
139  const char *SkipHexDigits(const char *ptr) {
140  while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
141  ptr++;
142  return ptr;
143  }
144 
145  /// SkipOctalDigits - Read and skip over any octal digits, up to End.
146  /// Return a pointer to the first non-hex digit or End.
147  const char *SkipOctalDigits(const char *ptr) {
148  while (ptr != ThisTokEnd &&
149  ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
150  ptr++;
151  return ptr;
152  }
153 
154  /// SkipDigits - Read and skip over any digits, up to End.
155  /// Return a pointer to the first non-hex digit or End.
156  const char *SkipDigits(const char *ptr) {
157  while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
158  ptr++;
159  return ptr;
160  }
161 
162  /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
163  /// Return a pointer to the first non-binary digit or End.
164  const char *SkipBinaryDigits(const char *ptr) {
165  while (ptr != ThisTokEnd &&
166  (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
167  ptr++;
168  return ptr;
169  }
170 
171 };
172 
173 /// CharLiteralParser - Perform interpretation and semantic analysis of a
174 /// character literal.
176  uint64_t Value;
178  bool IsMultiChar;
179  bool HadError;
180  SmallString<32> UDSuffixBuf;
181  unsigned UDSuffixOffset;
182 public:
183  CharLiteralParser(const char *begin, const char *end,
184  SourceLocation Loc, Preprocessor &PP,
186 
187  bool hadError() const { return HadError; }
188  bool isAscii() const { return Kind == tok::char_constant; }
189  bool isWide() const { return Kind == tok::wide_char_constant; }
190  bool isUTF8() const { return Kind == tok::utf8_char_constant; }
191  bool isUTF16() const { return Kind == tok::utf16_char_constant; }
192  bool isUTF32() const { return Kind == tok::utf32_char_constant; }
193  bool isMultiChar() const { return IsMultiChar; }
194  uint64_t getValue() const { return Value; }
195  StringRef getUDSuffix() const { return UDSuffixBuf; }
196  unsigned getUDSuffixOffset() const {
197  assert(!UDSuffixBuf.empty() && "no ud-suffix");
198  return UDSuffixOffset;
199  }
200 };
201 
202 /// StringLiteralParser - This decodes string escape characters and performs
203 /// wide string analysis and Translation Phase #6 (concatenation of string
204 /// literals) (C99 5.1.1.2p1).
206  const SourceManager &SM;
207  const LangOptions &Features;
208  const TargetInfo &Target;
209  DiagnosticsEngine *Diags;
210 
211  unsigned MaxTokenLength;
212  unsigned SizeBound;
213  unsigned CharByteWidth;
215  SmallString<512> ResultBuf;
216  char *ResultPtr; // cursor
217  SmallString<32> UDSuffixBuf;
218  unsigned UDSuffixToken;
219  unsigned UDSuffixOffset;
220 public:
222  Preprocessor &PP, bool Complain = true);
224  const SourceManager &sm, const LangOptions &features,
225  const TargetInfo &target,
226  DiagnosticsEngine *diags = nullptr)
227  : SM(sm), Features(features), Target(target), Diags(diags),
228  MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
229  ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
230  init(StringToks);
231  }
232 
233 
234  bool hadError;
235  bool Pascal;
236 
237  StringRef GetString() const {
238  return StringRef(ResultBuf.data(), GetStringLength());
239  }
240  unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
241 
242  unsigned GetNumStringChars() const {
243  return GetStringLength() / CharByteWidth;
244  }
245  /// getOffsetOfStringByte - This function returns the offset of the
246  /// specified byte of the string data represented by Token. This handles
247  /// advancing over escape sequences in the string.
248  ///
249  /// If the Diagnostics pointer is non-null, then this will do semantic
250  /// checking of the string literal and emit errors and warnings.
251  unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
252 
253  bool isAscii() const { return Kind == tok::string_literal; }
254  bool isWide() const { return Kind == tok::wide_string_literal; }
255  bool isUTF8() const { return Kind == tok::utf8_string_literal; }
256  bool isUTF16() const { return Kind == tok::utf16_string_literal; }
257  bool isUTF32() const { return Kind == tok::utf32_string_literal; }
258  bool isPascal() const { return Pascal; }
259 
260  StringRef getUDSuffix() const { return UDSuffixBuf; }
261 
262  /// Get the index of a token containing a ud-suffix.
263  unsigned getUDSuffixToken() const {
264  assert(!UDSuffixBuf.empty() && "no ud-suffix");
265  return UDSuffixToken;
266  }
267  /// Get the spelling offset of the first byte of the ud-suffix.
268  unsigned getUDSuffixOffset() const {
269  assert(!UDSuffixBuf.empty() && "no ud-suffix");
270  return UDSuffixOffset;
271  }
272 
273  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
274 
275 private:
276  void init(ArrayRef<Token> StringToks);
277  bool CopyStringFragment(const Token &Tok, const char *TokBegin,
278  StringRef Fragment);
279  void DiagnoseLexingError(SourceLocation Loc);
280 };
281 
282 } // end namespace clang
283 
284 #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:34
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:49
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:161
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:1586
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:17
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:24
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:123
StringRef getUDSuffix() const
LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:93
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:60
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:124