clang  11.0.0git
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  const SourceManager &SM;
44  const LangOptions &LangOpts;
45  DiagnosticsEngine &Diags;
46 
47  const char *const ThisTokBegin;
48  const char *const ThisTokEnd;
49  const char *DigitsBegin, *SuffixBegin; // markers
50  const char *s; // cursor
51 
52  unsigned radix;
53 
54  bool saw_exponent, saw_period, saw_ud_suffix, saw_fixed_point_suffix;
55 
56  SmallString<32> UDSuffixBuf;
57 
58 public:
59  NumericLiteralParser(StringRef TokSpelling, SourceLocation TokLoc,
60  const SourceManager &SM, const LangOptions &LangOpts,
61  const TargetInfo &Target, DiagnosticsEngine &Diags);
62  bool hadError : 1;
63  bool isUnsigned : 1;
64  bool isLong : 1; // This is *not* set for long long.
65  bool isLongLong : 1;
66  bool isHalf : 1; // 1.0h
67  bool isFloat : 1; // 1.0f
68  bool isImaginary : 1; // 1.0i
69  bool isFloat16 : 1; // 1.0f16
70  bool isFloat128 : 1; // 1.0q
71  uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
72 
73  bool isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
74  bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
75 
76  bool isFixedPointLiteral() const {
77  return (saw_period || saw_exponent) && saw_fixed_point_suffix;
78  }
79 
80  bool isIntegerLiteral() const {
81  return !saw_period && !saw_exponent && !isFixedPointLiteral();
82  }
83  bool isFloatingLiteral() const {
84  return (saw_period || saw_exponent) && !isFixedPointLiteral();
85  }
86 
87  bool hasUDSuffix() const {
88  return saw_ud_suffix;
89  }
90  StringRef getUDSuffix() const {
91  assert(saw_ud_suffix);
92  return UDSuffixBuf;
93  }
94  unsigned getUDSuffixOffset() const {
95  assert(saw_ud_suffix);
96  return SuffixBegin - ThisTokBegin;
97  }
98 
99  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
100 
101  unsigned getRadix() const { return radix; }
102 
103  /// GetIntegerValue - Convert this numeric literal value to an APInt that
104  /// matches Val's input width. If there is an overflow (i.e., if the unsigned
105  /// value read is larger than the APInt's bits will hold), set Val to the low
106  /// bits of the result and return true. Otherwise, return false.
107  bool GetIntegerValue(llvm::APInt &Val);
108 
109  /// GetFloatValue - Convert this numeric literal to a floating value, using
110  /// the specified APFloat fltSemantics (specifying float, double, etc).
111  /// The optional bool isExact (passed-by-reference) has its value
112  /// set to true if the returned APFloat can represent the number in the
113  /// literal exactly, and false otherwise.
114  llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
115 
116  /// GetFixedPointValue - Convert this numeric literal value into a
117  /// scaled integer that represents this value. Returns true if an overflow
118  /// occurred when calculating the integral part of the scaled integer or
119  /// calculating the digit sequence of the exponent.
120  bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale);
121 
122 private:
123 
124  void ParseNumberStartingWithZero(SourceLocation TokLoc);
125  void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
126 
127  static bool isDigitSeparator(char C) { return C == '\''; }
128 
129  /// Determine whether the sequence of characters [Start, End) contains
130  /// any real digits (not digit separators).
131  bool containsDigits(const char *Start, const char *End) {
132  return Start != End && (Start + 1 != End || !isDigitSeparator(Start[0]));
133  }
134 
135  enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
136 
137  /// Ensure that we don't have a digit separator here.
138  void checkSeparator(SourceLocation TokLoc, const char *Pos,
139  CheckSeparatorKind IsAfterDigits);
140 
141  /// SkipHexDigits - Read and skip over any hex digits, up to End.
142  /// Return a pointer to the first non-hex digit or End.
143  const char *SkipHexDigits(const char *ptr) {
144  while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
145  ptr++;
146  return ptr;
147  }
148 
149  /// SkipOctalDigits - Read and skip over any octal digits, up to End.
150  /// Return a pointer to the first non-hex digit or End.
151  const char *SkipOctalDigits(const char *ptr) {
152  while (ptr != ThisTokEnd &&
153  ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
154  ptr++;
155  return ptr;
156  }
157 
158  /// SkipDigits - Read and skip over any digits, up to End.
159  /// Return a pointer to the first non-hex digit or End.
160  const char *SkipDigits(const char *ptr) {
161  while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
162  ptr++;
163  return ptr;
164  }
165 
166  /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
167  /// Return a pointer to the first non-binary digit or End.
168  const char *SkipBinaryDigits(const char *ptr) {
169  while (ptr != ThisTokEnd &&
170  (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
171  ptr++;
172  return ptr;
173  }
174 
175 };
176 
177 /// CharLiteralParser - Perform interpretation and semantic analysis of a
178 /// character literal.
180  uint64_t Value;
182  bool IsMultiChar;
183  bool HadError;
184  SmallString<32> UDSuffixBuf;
185  unsigned UDSuffixOffset;
186 public:
187  CharLiteralParser(const char *begin, const char *end,
188  SourceLocation Loc, Preprocessor &PP,
190 
191  bool hadError() const { return HadError; }
192  bool isAscii() const { return Kind == tok::char_constant; }
193  bool isWide() const { return Kind == tok::wide_char_constant; }
194  bool isUTF8() const { return Kind == tok::utf8_char_constant; }
195  bool isUTF16() const { return Kind == tok::utf16_char_constant; }
196  bool isUTF32() const { return Kind == tok::utf32_char_constant; }
197  bool isMultiChar() const { return IsMultiChar; }
198  uint64_t getValue() const { return Value; }
199  StringRef getUDSuffix() const { return UDSuffixBuf; }
200  unsigned getUDSuffixOffset() const {
201  assert(!UDSuffixBuf.empty() && "no ud-suffix");
202  return UDSuffixOffset;
203  }
204 };
205 
206 /// StringLiteralParser - This decodes string escape characters and performs
207 /// wide string analysis and Translation Phase #6 (concatenation of string
208 /// literals) (C99 5.1.1.2p1).
210  const SourceManager &SM;
211  const LangOptions &Features;
212  const TargetInfo &Target;
213  DiagnosticsEngine *Diags;
214 
215  unsigned MaxTokenLength;
216  unsigned SizeBound;
217  unsigned CharByteWidth;
219  SmallString<512> ResultBuf;
220  char *ResultPtr; // cursor
221  SmallString<32> UDSuffixBuf;
222  unsigned UDSuffixToken;
223  unsigned UDSuffixOffset;
224 public:
226  Preprocessor &PP, bool Complain = true);
228  const SourceManager &sm, const LangOptions &features,
229  const TargetInfo &target,
230  DiagnosticsEngine *diags = nullptr)
231  : SM(sm), Features(features), Target(target), Diags(diags),
232  MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
233  ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
234  init(StringToks);
235  }
236 
237 
238  bool hadError;
239  bool Pascal;
240 
241  StringRef GetString() const {
242  return StringRef(ResultBuf.data(), GetStringLength());
243  }
244  unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
245 
246  unsigned GetNumStringChars() const {
247  return GetStringLength() / CharByteWidth;
248  }
249  /// getOffsetOfStringByte - This function returns the offset of the
250  /// specified byte of the string data represented by Token. This handles
251  /// advancing over escape sequences in the string.
252  ///
253  /// If the Diagnostics pointer is non-null, then this will do semantic
254  /// checking of the string literal and emit errors and warnings.
255  unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
256 
257  bool isAscii() const { return Kind == tok::string_literal; }
258  bool isWide() const { return Kind == tok::wide_string_literal; }
259  bool isUTF8() const { return Kind == tok::utf8_string_literal; }
260  bool isUTF16() const { return Kind == tok::utf16_string_literal; }
261  bool isUTF32() const { return Kind == tok::utf32_string_literal; }
262  bool isPascal() const { return Pascal; }
263 
264  StringRef getUDSuffix() const { return UDSuffixBuf; }
265 
266  /// Get the index of a token containing a ud-suffix.
267  unsigned getUDSuffixToken() const {
268  assert(!UDSuffixBuf.empty() && "no ud-suffix");
269  return UDSuffixToken;
270  }
271  /// Get the spelling offset of the first byte of the ud-suffix.
272  unsigned getUDSuffixOffset() const {
273  assert(!UDSuffixBuf.empty() && "no ud-suffix");
274  return UDSuffixOffset;
275  }
276 
277  static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
278 
279 private:
280  void init(ArrayRef<Token> StringToks);
281  bool CopyStringFragment(const Token &Tok, const char *TokBegin,
282  StringRef Fragment);
283  void DiagnoseLexingError(SourceLocation Loc);
284 };
285 
286 } // end namespace clang
287 
288 #endif
StringRef getUDSuffix() const
NumericLiteralParser(StringRef TokSpelling, SourceLocation TokLoc, const SourceManager &SM, const LangOptions &LangOpts, const TargetInfo &Target, DiagnosticsEngine &Diags)
integer-constant: [C99 6.4.4.1] decimal-constant integer-suffix octal-constant integer-suffix hexadec...
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:54
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:153
static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix)
Determine whether a suffix is a valid ud-suffix.
unsigned getUDSuffixOffset() const
Exposes information about the current target.
Definition: TargetInfo.h:179
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.
#define SM(sm)
Definition: Cuda.cpp:62
The result type of a method or function.
StringRef GetString() const
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:25
llvm::APInt APInt
Definition: Integral.h:27
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:128