1 //===--- LiteralSupport.h ---------------------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 // This file defines the NumericLiteralParser, CharLiteralParser, and
10 // StringLiteralParser interfaces.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_LEX_LITERALSUPPORT_H
15 #define LLVM_CLANG_LEX_LITERALSUPPORT_H
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"
28 class DiagnosticsEngine;
36 /// Copy characters from Input to Buf, expanding any UCNs.
37 void expandUCNs(SmallVectorImpl<char> &Buf, StringRef Input);
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.
42 class NumericLiteralParser {
43 Preprocessor &PP; // needed for diagnostics
45 const char *const ThisTokBegin;
46 const char *const ThisTokEnd;
47 const char *DigitsBegin, *SuffixBegin; // markers
48 const char *s; // cursor
52 bool saw_exponent, saw_period, saw_ud_suffix, saw_fixed_point_suffix;
54 SmallString<32> UDSuffixBuf;
57 NumericLiteralParser(StringRef TokSpelling,
58 SourceLocation TokLoc,
62 bool isLong : 1; // This is *not* set for long long.
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.
71 bool isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
72 bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
74 bool isFixedPointLiteral() const { return saw_fixed_point_suffix; }
76 bool isIntegerLiteral() const {
77 return !saw_period && !saw_exponent && !isFixedPointLiteral();
79 bool isFloatingLiteral() const {
80 return (saw_period || saw_exponent) && !isFixedPointLiteral();
83 bool hasUDSuffix() const {
86 StringRef getUDSuffix() const {
87 assert(saw_ud_suffix);
90 unsigned getUDSuffixOffset() const {
91 assert(saw_ud_suffix);
92 return SuffixBegin - ThisTokBegin;
95 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
97 unsigned getRadix() const { return radix; }
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);
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);
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);
120 void ParseNumberStartingWithZero(SourceLocation TokLoc);
121 void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
123 static bool isDigitSeparator(char C) { return C == '\''; }
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]));
131 enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
133 /// Ensure that we don't have a digit separator here.
134 void checkSeparator(SourceLocation TokLoc, const char *Pos,
135 CheckSeparatorKind IsAfterDigits);
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)))
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)))
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)))
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)))
173 /// CharLiteralParser - Perform interpretation and semantic analysis of a
174 /// character literal.
175 class CharLiteralParser {
180 SmallString<32> UDSuffixBuf;
181 unsigned UDSuffixOffset;
183 CharLiteralParser(const char *begin, const char *end,
184 SourceLocation Loc, Preprocessor &PP,
185 tok::TokenKind kind);
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;
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).
205 class StringLiteralParser {
206 const SourceManager &SM;
207 const LangOptions &Features;
208 const TargetInfo &Target;
209 DiagnosticsEngine *Diags;
211 unsigned MaxTokenLength;
213 unsigned CharByteWidth;
215 SmallString<512> ResultBuf;
216 char *ResultPtr; // cursor
217 SmallString<32> UDSuffixBuf;
218 unsigned UDSuffixToken;
219 unsigned UDSuffixOffset;
221 StringLiteralParser(ArrayRef<Token> StringToks,
222 Preprocessor &PP, bool Complain = true);
223 StringLiteralParser(ArrayRef<Token> StringToks,
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) {
237 StringRef GetString() const {
238 return StringRef(ResultBuf.data(), GetStringLength());
240 unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
242 unsigned GetNumStringChars() const {
243 return GetStringLength() / CharByteWidth;
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.
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;
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; }
260 StringRef getUDSuffix() const { return UDSuffixBuf; }
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;
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;
273 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
276 void init(ArrayRef<Token> StringToks);
277 bool CopyStringFragment(const Token &Tok, const char *TokBegin,
279 void DiagnoseLexingError(SourceLocation Loc);
282 } // end namespace clang