clang 20.0.0git
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
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/// Return true if the token corresponds to a function local predefined macro,
40/// which expands to a string literal, that can be concatenated with other
41/// string literals (only in Microsoft mode).
42bool isFunctionLocalStringLiteralMacro(tok::TokenKind K, const LangOptions &LO);
43
44/// Return true if the token is a string literal, or a function local
45/// predefined macro, which expands to a string literal.
46bool tokenIsLikeStringLiteral(const Token &Tok, const LangOptions &LO);
47
48/// NumericLiteralParser - This performs strict semantic analysis of the content
49/// of a ppnumber, classifying it as either integer, floating, or erroneous,
50/// determines the radix of the value and can convert it to a useful value.
52 const SourceManager &SM;
53 const LangOptions &LangOpts;
54 DiagnosticsEngine &Diags;
55
56 const char *const ThisTokBegin;
57 const char *const ThisTokEnd;
58 const char *DigitsBegin, *SuffixBegin; // markers
59 const char *s; // cursor
60
61 unsigned radix;
62
63 bool saw_exponent, saw_period, saw_ud_suffix, saw_fixed_point_suffix;
64
65 SmallString<32> UDSuffixBuf;
66
67public:
68 NumericLiteralParser(StringRef TokSpelling, SourceLocation TokLoc,
69 const SourceManager &SM, const LangOptions &LangOpts,
70 const TargetInfo &Target, DiagnosticsEngine &Diags);
71 bool hadError : 1;
72 bool isUnsigned : 1;
73 bool isLong : 1; // This is *not* set for long long.
74 bool isLongLong : 1;
75 bool isSizeT : 1; // 1z, 1uz (C++23)
76 bool isHalf : 1; // 1.0h
77 bool isFloat : 1; // 1.0f
78 bool isImaginary : 1; // 1.0i
79 bool isFloat16 : 1; // 1.0f16
80 bool isFloat128 : 1; // 1.0q
81 bool isFract : 1; // 1.0hr/r/lr/uhr/ur/ulr
82 bool isAccum : 1; // 1.0hk/k/lk/uhk/uk/ulk
83 bool isBitInt : 1; // 1wb, 1uwb (C23) or 1__wb, 1__uwb (Clang extension in C++
84 // mode)
85 uint8_t MicrosoftInteger; // Microsoft suffix extension i8, i16, i32, or i64.
86
87
88 bool isFixedPointLiteral() const {
89 return (saw_period || saw_exponent) && saw_fixed_point_suffix;
90 }
91
92 bool isIntegerLiteral() const {
93 return !saw_period && !saw_exponent && !isFixedPointLiteral();
94 }
95 bool isFloatingLiteral() const {
96 return (saw_period || saw_exponent) && !isFixedPointLiteral();
97 }
98
99 bool hasUDSuffix() const {
100 return saw_ud_suffix;
101 }
102 StringRef getUDSuffix() const {
103 assert(saw_ud_suffix);
104 return UDSuffixBuf;
105 }
106 unsigned getUDSuffixOffset() const {
107 assert(saw_ud_suffix);
108 return SuffixBegin - ThisTokBegin;
109 }
110
111 static bool isValidUDSuffix(const LangOptions &LangOpts, StringRef Suffix);
112
113 unsigned getRadix() const { return radix; }
114
115 /// GetIntegerValue - Convert this numeric literal value to an APInt that
116 /// matches Val's input width. If there is an overflow (i.e., if the unsigned
117 /// value read is larger than the APInt's bits will hold), set Val to the low
118 /// bits of the result and return true. Otherwise, return false.
119 bool GetIntegerValue(llvm::APInt &Val);
120
121 /// Convert this numeric literal to a floating value, using the specified
122 /// APFloat fltSemantics (specifying float, double, etc) and rounding mode.
123 llvm::APFloat::opStatus GetFloatValue(llvm::APFloat &Result,
124 llvm::RoundingMode RM);
125
126 /// GetFixedPointValue - Convert this numeric literal value into a
127 /// scaled integer that represents this value. Returns true if an overflow
128 /// occurred when calculating the integral part of the scaled integer or
129 /// calculating the digit sequence of the exponent.
130 bool GetFixedPointValue(llvm::APInt &StoreVal, unsigned Scale);
131
132 /// Get the digits that comprise the literal. This excludes any prefix or
133 /// suffix associated with the literal.
134 StringRef getLiteralDigits() const {
135 assert(!hadError && "cannot reliably get the literal digits with an error");
136 return StringRef(DigitsBegin, SuffixBegin - DigitsBegin);