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StringExtras.h
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1 //===- llvm/ADT/StringExtras.h - Useful string functions --------*- 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 contains some functions that are useful when dealing with strings.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_ADT_STRINGEXTRAS_H
15 #define LLVM_ADT_STRINGEXTRAS_H
16 
17 #include "llvm/ADT/ArrayRef.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/ADT/Twine.h"
21 #include <cassert>
22 #include <cstddef>
23 #include <cstdint>
24 #include <cstdlib>
25 #include <cstring>
26 #include <iterator>
27 #include <string>
28 #include <utility>
29 
30 namespace llvm {
31 
32 template<typename T> class SmallVectorImpl;
33 class raw_ostream;
34 
35 /// hexdigit - Return the hexadecimal character for the
36 /// given number \p X (which should be less than 16).
37 inline char hexdigit(unsigned X, bool LowerCase = false) {
38  const char HexChar = LowerCase ? 'a' : 'A';
39  return X < 10 ? '0' + X : HexChar + X - 10;
40 }
41 
42 /// Given an array of c-style strings terminated by a null pointer, construct
43 /// a vector of StringRefs representing the same strings without the terminating
44 /// null string.
45 inline std::vector<StringRef> toStringRefArray(const char *const *Strings) {
46  std::vector<StringRef> Result;
47  while (*Strings)
48  Result.push_back(*Strings++);
49  return Result;
50 }
51 
52 /// Construct a string ref from a boolean.
53 inline StringRef toStringRef(bool B) { return StringRef(B ? "true" : "false"); }
54 
55 /// Construct a string ref from an array ref of unsigned chars.
57  return StringRef(reinterpret_cast<const char *>(Input.begin()), Input.size());
58 }
59 
60 /// Construct a string ref from an array ref of unsigned chars.
62  return {Input.bytes_begin(), Input.bytes_end()};
63 }
64 
65 /// Interpret the given character \p C as a hexadecimal digit and return its
66 /// value.
67 ///
68 /// If \p C is not a valid hex digit, -1U is returned.
69 inline unsigned hexDigitValue(char C) {
70  if (C >= '0' && C <= '9') return C-'0';
71  if (C >= 'a' && C <= 'f') return C-'a'+10U;
72  if (C >= 'A' && C <= 'F') return C-'A'+10U;
73  return -1U;
74 }
75 
76 /// Checks if character \p C is one of the 10 decimal digits.
77 inline bool isDigit(char C) { return C >= '0' && C <= '9'; }
78 
79 /// Checks if character \p C is a hexadecimal numeric character.
80 inline bool isHexDigit(char C) { return hexDigitValue(C) != -1U; }
81 
82 /// Checks if character \p C is a valid letter as classified by "C" locale.
83 inline bool isAlpha(char C) {
84  return ('a' <= C && C <= 'z') || ('A' <= C && C <= 'Z');
85 }
86 
87 /// Checks whether character \p C is either a decimal digit or an uppercase or
88 /// lowercase letter as classified by "C" locale.
89 inline bool isAlnum(char C) { return isAlpha(C) || isDigit(C); }
90 
91 /// Checks whether character \p C is valid ASCII (high bit is zero).
92 inline bool isASCII(char C) { return static_cast<unsigned char>(C) <= 127; }
93 
94 /// Checks whether all characters in S are ASCII.
95 inline bool isASCII(llvm::StringRef S) {
96  for (char C : S)
97  if (LLVM_UNLIKELY(!isASCII(C)))
98  return false;
99  return true;
100 }
101 
102 /// Checks whether character \p C is printable.
103 ///
104 /// Locale-independent version of the C standard library isprint whose results
105 /// may differ on different platforms.
106 inline bool isPrint(char C) {
107  unsigned char UC = static_cast<unsigned char>(C);
108  return (0x20 <= UC) && (UC <= 0x7E);
109 }
110 
111 /// Returns the corresponding lowercase character if \p x is uppercase.
112 inline char toLower(char x) {
113  if (x >= 'A' && x <= 'Z')
114  return x - 'A' + 'a';
115  return x;
116 }
117 
118 /// Returns the corresponding uppercase character if \p x is lowercase.
119 inline char toUpper(char x) {
120  if (x >= 'a' && x <= 'z')
121  return x - 'a' + 'A';
122  return x;
123 }
124 
125 inline std::string utohexstr(uint64_t X, bool LowerCase = false) {
126  char Buffer[17];
127  char *BufPtr = std::end(Buffer);
128 
129  if (X == 0) *--BufPtr = '0';
130 
131  while (X) {
132  unsigned char Mod = static_cast<unsigned char>(X) & 15;
133  *--BufPtr = hexdigit(Mod, LowerCase);
134  X >>= 4;
135  }
136 
137  return std::string(BufPtr, std::end(Buffer));
138 }
139 
140 /// Convert buffer \p Input to its hexadecimal representation.
141 /// The returned string is double the size of \p Input.
142 inline std::string toHex(StringRef Input, bool LowerCase = false) {
143  static const char *const LUT = "0123456789ABCDEF";
144  const uint8_t Offset = LowerCase ? 32 : 0;
145  size_t Length = Input.size();
146 
147  std::string Output;
148  Output.reserve(2 * Length);
149  for (size_t i = 0; i < Length; ++i) {
150  const unsigned char c = Input[i];
151  Output.push_back(LUT[c >> 4] | Offset);
152  Output.push_back(LUT[c & 15] | Offset);
153  }
154  return Output;
155 }
156 
157 inline std::string toHex(ArrayRef<uint8_t> Input, bool LowerCase = false) {
158  return toHex(toStringRef(Input), LowerCase);
159 }
160 
161 inline uint8_t hexFromNibbles(char MSB, char LSB) {
162  unsigned U1 = hexDigitValue(MSB);
163  unsigned U2 = hexDigitValue(LSB);
164  assert(U1 != -1U && U2 != -1U);
165 
166  return static_cast<uint8_t>((U1 << 4) | U2);
167 }
168 
169 /// Convert hexadecimal string \p Input to its binary representation.
170 /// The return string is half the size of \p Input.
171 inline std::string fromHex(StringRef Input) {
172  if (Input.empty())
173  return std::string();
174 
175  std::string Output;
176  Output.reserve((Input.size() + 1) / 2);
177  if (Input.size() % 2 == 1) {
178  Output.push_back(hexFromNibbles('0', Input.front()));
179  Input = Input.drop_front();
180  }
181 
182  assert(Input.size() % 2 == 0);
183  while (!Input.empty()) {
184  uint8_t Hex = hexFromNibbles(Input[0], Input[1]);
185  Output.push_back(Hex);
186  Input = Input.drop_front(2);
187  }
188  return Output;
189 }
190 
191 /// Convert the string \p S to an integer of the specified type using
192 /// the radix \p Base. If \p Base is 0, auto-detects the radix.
193 /// Returns true if the number was successfully converted, false otherwise.
194 template <typename N> bool to_integer(StringRef S, N &Num, unsigned Base = 0) {
195  return !S.getAsInteger(Base, Num);
196 }
197 
198 namespace detail {
199 template <typename N>
200 inline bool to_float(const Twine &T, N &Num, N (*StrTo)(const char *, char **)) {
201  SmallString<32> Storage;
202  StringRef S = T.toNullTerminatedStringRef(Storage);
203  char *End;
204  N Temp = StrTo(S.data(), &End);
205  if (*End != '\0')
206  return false;
207  Num = Temp;
208  return true;
209 }
210 }
211 
212 inline bool to_float(const Twine &T, float &Num) {
213  return detail::to_float(T, Num, strtof);
214 }
215 
216 inline bool to_float(const Twine &T, double &Num) {
217  return detail::to_float(T, Num, strtod);
218 }
219 
220 inline bool to_float(const Twine &T, long double &Num) {
221  return detail::to_float(T, Num, strtold);
222 }
223 
224 inline std::string utostr(uint64_t X, bool isNeg = false) {
225  char Buffer[21];
226  char *BufPtr = std::end(Buffer);
227 
228  if (X == 0) *--BufPtr = '0'; // Handle special case...
229 
230  while (X) {
231  *--BufPtr = '0' + char(X % 10);
232  X /= 10;
233  }
234 
235  if (isNeg) *--BufPtr = '-'; // Add negative sign...
236  return std::string(BufPtr, std::end(Buffer));
237 }
238 
239 inline std::string itostr(int64_t X) {
240  if (X < 0)
241  return utostr(static_cast<uint64_t>(-X), true);
242  else
243  return utostr(static_cast<uint64_t>(X));
244 }
245 
246 /// StrInStrNoCase - Portable version of strcasestr. Locates the first
247 /// occurrence of string 's1' in string 's2', ignoring case. Returns
248 /// the offset of s2 in s1 or npos if s2 cannot be found.
250 
251 /// getToken - This function extracts one token from source, ignoring any
252 /// leading characters that appear in the Delimiters string, and ending the
253 /// token at any of the characters that appear in the Delimiters string. If
254 /// there are no tokens in the source string, an empty string is returned.
255 /// The function returns a pair containing the extracted token and the
256 /// remaining tail string.
257 std::pair<StringRef, StringRef> getToken(StringRef Source,
258  StringRef Delimiters = " \t\n\v\f\r");
259 
260 /// SplitString - Split up the specified string according to the specified
261 /// delimiters, appending the result fragments to the output list.
262 void SplitString(StringRef Source,
263  SmallVectorImpl<StringRef> &OutFragments,
264  StringRef Delimiters = " \t\n\v\f\r");
265 
266 /// Returns the English suffix for an ordinal integer (-st, -nd, -rd, -th).
267 inline StringRef getOrdinalSuffix(unsigned Val) {
268  // It is critically important that we do this perfectly for
269  // user-written sequences with over 100 elements.
270  switch (Val % 100) {
271  case 11:
272  case 12:
273  case 13:
274  return "th";
275  default:
276  switch (Val % 10) {
277  case 1: return "st";
278  case 2: return "nd";
279  case 3: return "rd";
280  default: return "th";
281  }
282  }
283 }
284 
285 /// Print each character of the specified string, escaping it if it is not
286 /// printable or if it is an escape char.
288 
289 /// Print each character of the specified string, escaping HTML special
290 /// characters.
291 void printHTMLEscaped(StringRef String, raw_ostream &Out);
292 
293 /// printLowerCase - Print each character as lowercase if it is uppercase.
294 void printLowerCase(StringRef String, raw_ostream &Out);
295 
296 namespace detail {
297 
298 template <typename IteratorT>
299 inline std::string join_impl(IteratorT Begin, IteratorT End,
300  StringRef Separator, std::input_iterator_tag) {
301  std::string S;
302  if (Begin == End)
303  return S;
304 
305  S += (*Begin);
306  while (++Begin != End) {
307  S += Separator;
308  S += (*Begin);
309  }
310  return S;
311 }
312 
313 template <typename IteratorT>
314 inline std::string join_impl(IteratorT Begin, IteratorT End,
315  StringRef Separator, std::forward_iterator_tag) {
316  std::string S;
317  if (Begin == End)
318  return S;
319 
320  size_t Len = (std::distance(Begin, End) - 1) * Separator.size();
321  for (IteratorT I = Begin; I != End; ++I)
322  Len += (*Begin).size();
323  S.reserve(Len);
324  S += (*Begin);
325  while (++Begin != End) {
326  S += Separator;
327  S += (*Begin);
328  }
329  return S;
330 }
331 
332 template <typename Sep>
333 inline void join_items_impl(std::string &Result, Sep Separator) {}
334 
335 template <typename Sep, typename Arg>
336 inline void join_items_impl(std::string &Result, Sep Separator,
337  const Arg &Item) {
338  Result += Item;
339 }
340 
341 template <typename Sep, typename Arg1, typename... Args>
342 inline void join_items_impl(std::string &Result, Sep Separator, const Arg1 &A1,
343  Args &&... Items) {
344  Result += A1;
345  Result += Separator;
346  join_items_impl(Result, Separator, std::forward<Args>(Items)...);
347 }
348 
349 inline size_t join_one_item_size(char C) { return 1; }
350 inline size_t join_one_item_size(const char *S) { return S ? ::strlen(S) : 0; }
351 
352 template <typename T> inline size_t join_one_item_size(const T &Str) {
353  return Str.size();
354 }
355 
356 inline size_t join_items_size() { return 0; }
357 
358 template <typename A1> inline size_t join_items_size(const A1 &A) {
359  return join_one_item_size(A);
360 }
361 template <typename A1, typename... Args>
362 inline size_t join_items_size(const A1 &A, Args &&... Items) {
363  return join_one_item_size(A) + join_items_size(std::forward<Args>(Items)...);
364 }
365 
366 } // end namespace detail
367 
368 /// Joins the strings in the range [Begin, End), adding Separator between
369 /// the elements.
370 template <typename IteratorT>
371 inline std::string join(IteratorT Begin, IteratorT End, StringRef Separator) {
372  using tag = typename std::iterator_traits<IteratorT>::iterator_category;
373  return detail::join_impl(Begin, End, Separator, tag());
374 }
375 
376 /// Joins the strings in the range [R.begin(), R.end()), adding Separator
377 /// between the elements.
378 template <typename Range>
379 inline std::string join(Range &&R, StringRef Separator) {
380  return join(R.begin(), R.end(), Separator);
381 }
382 
383 /// Joins the strings in the parameter pack \p Items, adding \p Separator
384 /// between the elements. All arguments must be implicitly convertible to
385 /// std::string, or there should be an overload of std::string::operator+=()
386 /// that accepts the argument explicitly.
387 template <typename Sep, typename... Args>
388 inline std::string join_items(Sep Separator, Args &&... Items) {
389  std::string Result;
390  if (sizeof...(Items) == 0)
391  return Result;
392 
393  size_t NS = detail::join_one_item_size(Separator);
394  size_t NI = detail::join_items_size(std::forward<Args>(Items)...);
395  Result.reserve(NI + (sizeof...(Items) - 1) * NS + 1);
396  detail::join_items_impl(Result, Separator, std::forward<Args>(Items)...);
397  return Result;
398 }
399 
400 } // end namespace llvm
401 
402 #endif // LLVM_ADT_STRINGEXTRAS_H
bool to_float(const Twine &T, N &Num, N(*StrTo)(const char *, char **))
Definition: StringExtras.h:200
uint64_t CallInst * C
const_iterator end(StringRef path)
Get end iterator over path.
Definition: Path.cpp:259
std::string join_items(Sep Separator, Args &&... Items)
Joins the strings in the parameter pack Items, adding Separator between the elements.
Definition: StringExtras.h:388
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
bool isPrint(char C)
Checks whether character C is printable.
Definition: StringExtras.h:106
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
const unsigned char * bytes_end() const
Definition: StringRef.h:113
bool to_integer(StringRef S, N &Num, unsigned Base=0)
Convert the string S to an integer of the specified type using the radix Base.
Definition: StringExtras.h:194
iterator begin() const
Definition: ArrayRef.h:137
size_t join_items_size()
Definition: StringExtras.h:356
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE size_t size() const
size - Get the string size.
Definition: StringRef.h:138
bool isASCII(char C)
Checks whether character C is valid ASCII (high bit is zero).
Definition: StringExtras.h:92
void printEscapedString(StringRef Name, raw_ostream &Out)
Print each character of the specified string, escaping it if it is not printable or if it is an escap...
ArrayRef< uint8_t > arrayRefFromStringRef(StringRef Input)
Construct a string ref from an array ref of unsigned chars.
Definition: StringExtras.h:61
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE const char * data() const
data - Get a pointer to the start of the string (which may not be null terminated).
Definition: StringRef.h:128
std::string fromHex(StringRef Input)
Convert hexadecimal string Input to its binary representation.
Definition: StringExtras.h:171
#define LLVM_UNLIKELY(EXPR)
Definition: Compiler.h:192
amdgpu Simplify well known AMD library false Value Value const Twine & Name
bool isAlnum(char C)
Checks whether character C is either a decimal digit or an uppercase or lowercase letter as classifie...
Definition: StringExtras.h:89
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
std::string join(IteratorT Begin, IteratorT End, StringRef Separator)
Joins the strings in the range [Begin, End), adding Separator between the elements.
Definition: StringExtras.h:371
void SplitString(StringRef Source, SmallVectorImpl< StringRef > &OutFragments, StringRef Delimiters=" \\\)
SplitString - Split up the specified string according to the specified delimiters, appending the result fragments to the output list.
std::pair< StringRef, StringRef > getToken(StringRef Source, StringRef Delimiters=" \\\)
getToken - This function extracts one token from source, ignoring any leading characters that appear ...
std::string itostr(int64_t X)
Definition: StringExtras.h:239
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:133
char hexdigit(unsigned X, bool LowerCase=false)
hexdigit - Return the hexadecimal character for the given number X (which should be less than 16)...
Definition: StringExtras.h:37
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
void join_items_impl(std::string &Result, Sep Separator)
Definition: StringExtras.h:333
size_t size() const
size - Get the array size.
Definition: ArrayRef.h:149
bool isHexDigit(char C)
Checks if character C is a hexadecimal numeric character.
Definition: StringExtras.h:80
StringRef toNullTerminatedStringRef(SmallVectorImpl< char > &Out) const
This returns the twine as a single null terminated StringRef if it can be represented as such...
Definition: Twine.cpp:38
bool isAlpha(char C)
Checks if character C is a valid letter as classified by "C" locale.
Definition: StringExtras.h:83
char toLower(char x)
Returns the corresponding lowercase character if x is uppercase.
Definition: StringExtras.h:112
StringRef toStringRef(bool B)
Construct a string ref from a boolean.
Definition: StringExtras.h:53
size_t join_one_item_size(char C)
Definition: StringExtras.h:349
std::enable_if< std::numeric_limits< T >::is_signed, bool >::type getAsInteger(unsigned Radix, T &Result) const
Parse the current string as an integer of the specified radix.
Definition: StringRef.h:497
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef drop_front(size_t N=1) const
Return a StringRef equal to &#39;this&#39; but with the first N elements dropped.
Definition: StringRef.h:645
std::string utostr(uint64_t X, bool isNeg=false)
Definition: StringExtras.h:224
The access may modify the value stored in memory.
unsigned hexDigitValue(char C)
Interpret the given character C as a hexadecimal digit and return its value.
Definition: StringExtras.h:69
amdgpu Simplify well known AMD library false Value Value * Arg
bool isDigit(char C)
Checks if character C is one of the 10 decimal digits.
Definition: StringExtras.h:77
const unsigned char * bytes_begin() const
Definition: StringRef.h:110
#define I(x, y, z)
Definition: MD5.cpp:58
#define N
StringRef::size_type StrInStrNoCase(StringRef s1, StringRef s2)
StrInStrNoCase - Portable version of strcasestr.
StringRef getOrdinalSuffix(unsigned Val)
Returns the English suffix for an ordinal integer (-st, -nd, -rd, -th).
Definition: StringExtras.h:267
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
char toUpper(char x)
Returns the corresponding uppercase character if x is lowercase.
Definition: StringExtras.h:119
LLVM_NODISCARD char front() const
front - Get the first character in the string.
Definition: StringRef.h:142
void printLowerCase(StringRef String, raw_ostream &Out)
printLowerCase - Print each character as lowercase if it is uppercase.
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:46
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
uint8_t hexFromNibbles(char MSB, char LSB)
Definition: StringExtras.h:161
std::string toHex(StringRef Input, bool LowerCase=false)
Convert buffer Input to its hexadecimal representation.
Definition: StringExtras.h:142
void printHTMLEscaped(StringRef String, raw_ostream &Out)
Print each character of the specified string, escaping HTML special characters.
constexpr char Args[]
Key for Kernel::Metadata::mArgs.
std::string join_impl(IteratorT Begin, IteratorT End, StringRef Separator, std::input_iterator_tag)
Definition: StringExtras.h:299
std::vector< StringRef > toStringRefArray(const char *const *Strings)
Given an array of c-style strings terminated by a null pointer, construct a vector of StringRefs repr...
Definition: StringExtras.h:45
std::string utohexstr(uint64_t X, bool LowerCase=false)
Definition: StringExtras.h:125