clang 17.0.0git
LiteralSupport.h
Go to the documentation of this file.
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
18#include "clang/Basic/LLVM.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
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.
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
58public:
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 isSizeT : 1; // 1z, 1uz (C++23)
67 bool isHalf : 1; // 1.0h
68 bool isFloat : 1; // 1.0f
69 bool isImaginary : 1; // 1.0i
70 bool isFloat16 : 1; // 1.0f16
71 bool isFloat128 : 1; // 1.0q
72 bool isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
73 bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
74 bool isBitInt : 1; // 1wb, 1uwb (C2x)
75 uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
76
77
78 bool isFixedPointLiteral() const {
79 return (saw_period || saw_exponent) && saw_fixed_point_suffix;
80 }
81
82 bool isIntegerLiteral() const {
83 return !saw_period && !saw_exponent && !isFixedPointLiteral();
84 }
85 bool isFloatingLiteral() const {
86 return (saw_period || saw_exponent) && !isFixedPointLiteral();
87 }
88
89 bool hasUDSuffix() const {
90 return saw_ud_suffix;
91 }
92 StringRef getUDSuffix() const {
93 assert(saw_ud_suffix);
94 return UDSuffixBuf;
95 }
96 unsigned getUDSuffixOffset() const {
97 assert(saw_ud_suffix);
98 return SuffixBegin - ThisTokBegin;
99 }
100
101 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
102
103 unsigned getRadix() const { return radix; }
104
105 /// GetIntegerValue - Convert this numeric literal value to an APInt that
106 /// matches Val's input width. If there is an overflow (i.e., if the unsigned
107 /// value read is larger than the APInt's bits will hold), set Val to the low
108 /// bits of the result and return true. Otherwise, return false.
109 bool GetIntegerValue(llvm::APInt &Val);
110
111 /// GetFloatValue - Convert this numeric literal to a floating value, using
112 /// the specified APFloat fltSemantics (specifying float, double, etc).
113 /// The optional bool isExact (passed-by-reference) has its value
114 /// set to true if the returned APFloat can represent the number in the
115 /// literal exactly, and false otherwise.
116 llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
117
118 /// GetFixedPointValue - Convert this numeric literal value into a
119 /// scaled integer that represents this value. Returns true if an overflow
120 /// occurred when calculating the integral part of the scaled integer or
121 /// calculating the digit sequence of the exponent.
122 bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale);
123
124 /// Get the digits that comprise the literal. This excludes any prefix or
125 /// suffix associated with the literal.
126 StringRef getLiteralDigits() const {
127 assert(!hadError && "cannot reliably get the literal digits with an error");
128 return StringRef(DigitsBegin, SuffixBegin - DigitsBegin);
129 }
130
131private:
132
133 void ParseNumberStartingWithZero(SourceLocation TokLoc);
134 void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
135
136 static bool isDigitSeparator(char C) { return C == '\''; }
137
138 /// Determine whether the sequence of characters [Start, End) contains
139 /// any real digits (not digit separators).
140 bool containsDigits(const char *Start, const char *End) {
141 return Start != End && (Start + 1 != End || !isDigitSeparator(Start[0]));
142 }
143
144 enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
145
146 /// Ensure that we don't have a digit separator here.
147 void checkSeparator(SourceLocation TokLoc, const char *Pos,
148 CheckSeparatorKind IsAfterDigits);
149
150 /// SkipHexDigits - Read and skip over any hex digits, up to End.
151 /// Return a pointer to the first non-hex digit or End.
152 const char *SkipHexDigits(const char *ptr) {
153 while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
154 ptr++;
155 return ptr;
156 }
157
158 /// SkipOctalDigits - Read and skip over any octal digits, up to End.
159 /// Return a pointer to the first non-hex digit or End.
160 const char *SkipOctalDigits(const char *ptr) {
161 while (ptr != ThisTokEnd &&
162 ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
163 ptr++;
164 return ptr;
165 }
166
167 /// SkipDigits - Read and skip over any digits, up to End.
168 /// Return a pointer to the first non-hex digit or End.
169 const char *SkipDigits(const char *ptr) {
170 while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
171 ptr++;
172 return ptr;
173 }
174
175 /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
176 /// Return a pointer to the first non-binary digit or End.
177 const char *SkipBinaryDigits(const char *ptr) {
178 while (ptr != ThisTokEnd &&
179 (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
180 ptr++;
181 return ptr;
182 }
183
184};
185
186/// CharLiteralParser - Perform interpretation and semantic analysis of a
187/// character literal.
189 uint64_t Value;
190 tok::TokenKind Kind;
191 bool IsMultiChar;
192 bool HadError;
193 SmallString<32> UDSuffixBuf;
194 unsigned UDSuffixOffset;
195public:
196 CharLiteralParser(const char *begin, const char *end,
198 tok::TokenKind kind);
199
200 bool hadError() const { return HadError; }
201 bool isOrdinary() const { return Kind == tok::char_constant; }
202 bool isWide() const { return Kind == tok::wide_char_constant; }
203 bool isUTF8() const { return Kind == tok::utf8_char_constant; }
204 bool isUTF16() const { return Kind == tok::utf16_char_constant; }
205 bool isUTF32() const { return Kind == tok::utf32_char_constant; }
206 bool isMultiChar() const { return IsMultiChar; }
207 uint64_t getValue() const { return Value; }
208 StringRef getUDSuffix() const { return UDSuffixBuf; }
209 unsigned getUDSuffixOffset() const {
210 assert(!UDSuffixBuf.empty() && "no ud-suffix");
211 return UDSuffixOffset;
212 }
213};
214
215/// StringLiteralParser - This decodes string escape characters and performs
216/// wide string analysis and Translation Phase #6 (concatenation of string
217/// literals) (C99 5.1.1.2p1).
219 const SourceManager &SM;
220 const LangOptions &Features;
221 const TargetInfo &Target;
222 DiagnosticsEngine *Diags;
223
224 unsigned MaxTokenLength;
225 unsigned SizeBound;
226 unsigned CharByteWidth;
227 tok::TokenKind Kind;
228 SmallString<512> ResultBuf;
229 char *ResultPtr; // cursor
230 SmallString<32> UDSuffixBuf;
231 unsigned UDSuffixToken;
232 unsigned UDSuffixOffset;
233public:
235 Preprocessor &PP);
237 const SourceManager &sm, const LangOptions &features,
238 const TargetInfo &target,
239 DiagnosticsEngine *diags = nullptr)
240 : SM(sm), Features(features), Target(target), Diags(diags),
241 MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
242 ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
243 init(StringToks);
244 }
245
246
248 bool Pascal;
249
250 StringRef GetString() const {
251 return StringRef(ResultBuf.data(), GetStringLength());
252 }
253 unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
254
255 unsigned GetNumStringChars() const {
256 return GetStringLength() / CharByteWidth;
257 }
258 /// getOffsetOfStringByte - This function returns the offset of the
259 /// specified byte of the string data represented by Token. This handles
260 /// advancing over escape sequences in the string.
261 ///
262 /// If the Diagnostics pointer is non-null, then this will do semantic
263 /// checking of the string literal and emit errors and warnings.
264 unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
265
266 bool isOrdinary() const { return Kind == tok::string_literal; }
267 bool isWide() const { return Kind == tok::wide_string_literal; }
268 bool isUTF8() const { return Kind == tok::utf8_string_literal; }
269 bool isUTF16() const { return Kind == tok::utf16_string_literal; }
270 bool isUTF32() const { return Kind == tok::utf32_string_literal; }
271 bool isPascal() const { return Pascal; }
272
273 StringRef getUDSuffix() const { return UDSuffixBuf; }
274
275 /// Get the index of a token containing a ud-suffix.
276 unsigned getUDSuffixToken() const {
277 assert(!UDSuffixBuf.empty() && "no ud-suffix");
278 return UDSuffixToken;
279 }
280 /// Get the spelling offset of the first byte of the ud-suffix.
281 unsigned getUDSuffixOffset() const {
282 assert(!UDSuffixBuf.empty() && "no ud-suffix");
283 return UDSuffixOffset;
284 }
285
286 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
287
288private:
289 void init(ArrayRef<Token> StringToks);
290 bool CopyStringFragment(const Token &Tok, const char *TokBegin,
291 StringRef Fragment);
292 void DiagnoseLexingError(SourceLocation Loc);
293};
294
295} // end namespace clang
296
297#endif
#define SM(sm)
Definition: Cuda.cpp:80
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified.
Defines the clang::TokenKind enum and support functions.
CharLiteralParser - Perform interpretation and semantic analysis of a character literal.
unsigned getUDSuffixOffset() const
StringRef getUDSuffix() const
uint64_t getValue() const
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:192
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:82
NumericLiteralParser - This performs strict semantic analysis of the content of a ppnumber,...
StringRef getUDSuffix() const
llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result)
GetFloatValue - Convert this numeric literal to a floating value, using the specified APFloat fltSema...
static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix)
Determine whether a suffix is a valid ud-suffix.
bool GetIntegerValue(llvm::APInt &Val)
GetIntegerValue - Convert this numeric literal value to an APInt that matches Val's input width.
unsigned getUDSuffixOffset() const
StringRef getLiteralDigits() const
Get the digits that comprise the literal.
bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale)
GetFixedPointValue - Convert this numeric literal value into a scaled integer that represents this va...
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:128
Encodes a location in the source.
This class handles loading and caching of source files into memory.
StringLiteralParser - This decodes string escape characters and performs wide string analysis and Tra...
unsigned getUDSuffixToken() const
Get the index of a token containing a ud-suffix.
unsigned getUDSuffixOffset() const
Get the spelling offset of the first byte of the ud-suffix.
unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const
getOffsetOfStringByte - This function returns the offset of the specified byte of the string data rep...
StringRef getUDSuffix() const
unsigned GetStringLength() const
StringLiteralParser(ArrayRef< Token > StringToks, const SourceManager &sm, const LangOptions &features, const TargetInfo &target, DiagnosticsEngine *diags=nullptr)
static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix)
Determine whether a suffix is a valid ud-suffix.
unsigned GetNumStringChars() const
StringRef GetString() const
Exposes information about the current target.
Definition: TargetInfo.h:206
Token - This structure provides full information about a lexed token.
Definition: Token.h:35
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.
@ C
Languages that the frontend can parse and compile.
@ Result
The result type of a method or function.
LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:99
LLVM_READONLY bool isHexDigit(unsigned char c)
Return true if this character is an ASCII hex digit: [0-9a-fA-F].
Definition: CharInfo.h:129
#define false
Definition: stdbool.h:22