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
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 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++2b)
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 uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
73
74 bool isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
75 bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
76
77 bool isFixedPointLiteral() const {
78 return (saw_period || saw_exponent) && saw_fixed_point_suffix;
79 }
80
81 bool isIntegerLiteral() const {
82 return !saw_period && !saw_exponent && !isFixedPointLiteral();
83 }
84 bool isFloatingLiteral() const {
85 return (saw_period || saw_exponent) && !isFixedPointLiteral();
86 }
87
88 bool hasUDSuffix() const {
89 return saw_ud_suffix;
90 }
91 StringRef getUDSuffix() const {
92 assert(saw_ud_suffix);
93 return UDSuffixBuf;
94 }
95 unsigned getUDSuffixOffset() const {
96 assert(saw_ud_suffix);
97 return SuffixBegin - ThisTokBegin;
98 }
99
100 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
101
102 unsigned getRadix() const { return radix; }
103
104 /// GetIntegerValue - Convert this numeric literal value to an APInt that
105 /// matches Val's input width. If there is an overflow (i.e., if the unsigned
106 /// value read is larger than the APInt's bits will hold), set Val to the low
107 /// bits of the result and return true. Otherwise, return false.
108 bool GetIntegerValue(llvm::APInt &Val);
109
110 /// GetFloatValue - Convert this numeric literal to a floating value, using
111 /// the specified APFloat fltSemantics (specifying float, double, etc).
112 /// The optional bool isExact (passed-by-reference) has its value
113 /// set to true if the returned APFloat can represent the number in the
114 /// literal exactly, and false otherwise.
115 llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result);
116
117 /// GetFixedPointValue - Convert this numeric literal value into a
118 /// scaled integer that represents this value. Returns true if an overflow
119 /// occurred when calculating the integral part of the scaled integer or
120 /// calculating the digit sequence of the exponent.
121 bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale);
122
123private:
124
125 void ParseNumberStartingWithZero(SourceLocation TokLoc);
126 void ParseDecimalOrOctalCommon(SourceLocation TokLoc);
127
128 static bool isDigitSeparator(char C) { return C == '\''; }
129
130 /// Determine whether the sequence of characters [Start, End) contains
131 /// any real digits (not digit separators).
132 bool containsDigits(const char *Start, const char *End) {
133 return Start != End && (Start + 1 != End || !isDigitSeparator(Start[0]));
134 }
135
136 enum CheckSeparatorKind { CSK_BeforeDigits, CSK_AfterDigits };
137
138 /// Ensure that we don't have a digit separator here.
139 void checkSeparator(SourceLocation TokLoc, const char *Pos,
140 CheckSeparatorKind IsAfterDigits);
141
142 /// SkipHexDigits - Read and skip over any hex digits, up to End.
143 /// Return a pointer to the first non-hex digit or End.
144 const char *SkipHexDigits(const char *ptr) {
145 while (ptr != ThisTokEnd && (isHexDigit(*ptr) || isDigitSeparator(*ptr)))
146 ptr++;
147 return ptr;
148 }
149
150 /// SkipOctalDigits - Read and skip over any octal digits, up to End.
151 /// Return a pointer to the first non-hex digit or End.
152 const char *SkipOctalDigits(const char *ptr) {
153 while (ptr != ThisTokEnd &&
154 ((*ptr >= '0' && *ptr <= '7') || isDigitSeparator(*ptr)))
155 ptr++;
156 return ptr;
157 }
158
159 /// SkipDigits - Read and skip over any digits, up to End.
160 /// Return a pointer to the first non-hex digit or End.
161 const char *SkipDigits(const char *ptr) {
162 while (ptr != ThisTokEnd && (isDigit(*ptr) || isDigitSeparator(*ptr)))
163 ptr++;
164 return ptr;
165 }
166
167 /// SkipBinaryDigits - Read and skip over any binary digits, up to End.
168 /// Return a pointer to the first non-binary digit or End.
169 const char *SkipBinaryDigits(const char *ptr) {
170 while (ptr != ThisTokEnd &&
171 (*ptr == '0' || *ptr == '1' || isDigitSeparator(*ptr)))
172 ptr++;
173 return ptr;
174 }
175
176};
177
178/// CharLiteralParser - Perform interpretation and semantic analysis of a
179/// character literal.
180class CharLiteralParser {
181 uint64_t Value;
182 tok::TokenKind Kind;
183 bool IsMultiChar;
184 bool HadError;
185 SmallString<32> UDSuffixBuf;
186 unsigned UDSuffixOffset;
187public:
188 CharLiteralParser(const char *begin, const char *end,
189 SourceLocation Loc, Preprocessor &PP,
190 tok::TokenKind kind);
191
192 bool hadError() const { return HadError; }
193 bool isAscii() const { return Kind == tok::char_constant; }
194 bool isWide() const { return Kind == tok::wide_char_constant; }
195 bool isUTF8() const { return Kind == tok::utf8_char_constant; }
196 bool isUTF16() const { return Kind == tok::utf16_char_constant; }
197 bool isUTF32() const { return Kind == tok::utf32_char_constant; }
198 bool isMultiChar() const { return IsMultiChar; }
199 uint64_t getValue() const { return Value; }
200 StringRef getUDSuffix() const { return UDSuffixBuf; }
201 unsigned getUDSuffixOffset() const {
202 assert(!UDSuffixBuf.empty() && "no ud-suffix");
203 return UDSuffixOffset;
204 }
205};
206
207/// StringLiteralParser - This decodes string escape characters and performs
208/// wide string analysis and Translation Phase #6 (concatenation of string
209/// literals) (C99 5.1.1.2p1).
210class StringLiteralParser {
211 const SourceManager &SM;
212 const LangOptions &Features;
213 const TargetInfo &Target;
214 DiagnosticsEngine *Diags;
215
216 unsigned MaxTokenLength;
217 unsigned SizeBound;
218 unsigned CharByteWidth;
219 tok::TokenKind Kind;
220 SmallString<512> ResultBuf;
221 char *ResultPtr; // cursor
222 SmallString<32> UDSuffixBuf;
223 unsigned UDSuffixToken;
224 unsigned UDSuffixOffset;
225public:
226 StringLiteralParser(ArrayRef<Token> StringToks,
227 Preprocessor &PP, bool Complain = true);
228 StringLiteralParser(ArrayRef<Token> StringToks,
229 const SourceManager &sm, const LangOptions &features,
230 const TargetInfo &target,
231 DiagnosticsEngine *diags = nullptr)
232 : SM(sm), Features(features), Target(target), Diags(diags),
233 MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
234 ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
235 init(StringToks);
236 }
237
238
239 bool hadError;
240 bool Pascal;
241
242 StringRef GetString() const {
243 return StringRef(ResultBuf.data(), GetStringLength());
244 }
245 unsigned GetStringLength() const { return ResultPtr-ResultBuf.data(); }
246
247 unsigned GetNumStringChars() const {
248 return GetStringLength() / CharByteWidth;
249 }
250 /// getOffsetOfStringByte - This function returns the offset of the
251 /// specified byte of the string data represented by Token. This handles
252 /// advancing over escape sequences in the string.
253 ///
254 /// If the Diagnostics pointer is non-null, then this will do semantic
255 /// checking of the string literal and emit errors and warnings.
256 unsigned getOffsetOfStringByte(const Token &TheTok, unsigned ByteNo) const;
257
258 bool isAscii() const { return Kind == tok::string_literal; }
259 bool isWide() const { return Kind == tok::wide_string_literal; }
260 bool isUTF8() const { return Kind == tok::utf8_string_literal; }
261 bool isUTF16() const { return Kind == tok::utf16_string_literal; }
262 bool isUTF32() const { return Kind == tok::utf32_string_literal; }
263 bool isPascal() const { return Pascal; }
264
265 StringRef getUDSuffix() const { return UDSuffixBuf; }
266
267 /// Get the index of a token containing a ud-suffix.
268 unsigned getUDSuffixToken() const {
269 assert(!UDSuffixBuf.empty() && "no ud-suffix");
270 return UDSuffixToken;
271 }
272 /// Get the spelling offset of the first byte of the ud-suffix.
273 unsigned getUDSuffixOffset() const {
274 assert(!UDSuffixBuf.empty() && "no ud-suffix");
275 return UDSuffixOffset;
276 }
277
278 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
279
280private:
281 void init(ArrayRef<Token> StringToks);
282 bool CopyStringFragment(const Token &Tok, const char *TokBegin,
283 StringRef Fragment);
284 void DiagnoseLexingError(SourceLocation Loc);
285};
286
287} // end namespace clang
288
289#endif
290