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 CLANG_LITERALSUPPORT_H
16#define CLANG_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
26namespace clang {
27
28class DiagnosticsEngine;
29class Preprocessor;
30class Token;
31class SourceLocation;
32class TargetInfo;
33class SourceManager;
34class LangOptions;
35
36/// Copy characters from Input to Buf, expanding any UCNs.
37void 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.
42class NumericLiteralParser {
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
56public:
57  NumericLiteralParser(StringRef TokSpelling,
58                       SourceLocation TokLoc,
59                       Preprocessor &PP);
60  bool hadError;
61  bool isUnsigned;
62  bool isLong;        // This is *not* set for long long.
63  bool isLongLong;
64  bool isFloat;       // 1.0f
65  bool isImaginary;   // 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
104private:
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.
154class CharLiteralParser {
155  uint64_t Value;
156  tok::TokenKind Kind;
157  bool IsMultiChar;
158  bool HadError;
159  SmallString<32> UDSuffixBuf;
160  unsigned UDSuffixOffset;
161public:
162  CharLiteralParser(const char *begin, const char *end,
163                    SourceLocation Loc, Preprocessor &PP,
164                    tok::TokenKind kind);
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).
183class StringLiteralParser {
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;
192  tok::TokenKind Kind;
193  SmallString<512> ResultBuf;
194  char *ResultPtr; // cursor
195  SmallString<32> UDSuffixBuf;
196  unsigned UDSuffixToken;
197  unsigned UDSuffixOffset;
198public:
199  StringLiteralParser(ArrayRef<Token> StringToks,
200                      Preprocessor &PP, bool Complain = true);
201  StringLiteralParser(ArrayRef<Token> StringToks,
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
251private:
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
261