LLVM  16.0.0git
Twine.h
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1 //===- Twine.h - Fast Temporary String Concatenation ------------*- 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 #ifndef LLVM_ADT_TWINE_H
10 #define LLVM_ADT_TWINE_H
11 
12 #include "llvm/ADT/SmallVector.h"
13 #include "llvm/ADT/StringRef.h"
15 #include <cassert>
16 #include <cstdint>
17 #include <string>
18 #include <string_view>
19 
20 namespace llvm {
21 
22  class formatv_object_base;
23  class raw_ostream;
24 
25  /// Twine - A lightweight data structure for efficiently representing the
26  /// concatenation of temporary values as strings.
27  ///
28  /// A Twine is a kind of rope, it represents a concatenated string using a
29  /// binary-tree, where the string is the preorder of the nodes. Since the
30  /// Twine can be efficiently rendered into a buffer when its result is used,
31  /// it avoids the cost of generating temporary values for intermediate string
32  /// results -- particularly in cases when the Twine result is never
33  /// required. By explicitly tracking the type of leaf nodes, we can also avoid
34  /// the creation of temporary strings for conversions operations (such as
35  /// appending an integer to a string).
36  ///
37  /// A Twine is not intended for use directly and should not be stored, its
38  /// implementation relies on the ability to store pointers to temporary stack
39  /// objects which may be deallocated at the end of a statement. Twines should
40  /// only be used accepted as const references in arguments, when an API wishes
41  /// to accept possibly-concatenated strings.
42  ///
43  /// Twines support a special 'null' value, which always concatenates to form
44  /// itself, and renders as an empty string. This can be returned from APIs to
45  /// effectively nullify any concatenations performed on the result.
46  ///
47  /// \b Implementation
48  ///
49  /// Given the nature of a Twine, it is not possible for the Twine's
50  /// concatenation method to construct interior nodes; the result must be
51  /// represented inside the returned value. For this reason a Twine object
52  /// actually holds two values, the left- and right-hand sides of a
53  /// concatenation. We also have nullary Twine objects, which are effectively
54  /// sentinel values that represent empty strings.
55  ///
56  /// Thus, a Twine can effectively have zero, one, or two children. The \see
57  /// isNullary(), \see isUnary(), and \see isBinary() predicates exist for
58  /// testing the number of children.
59  ///
60  /// We maintain a number of invariants on Twine objects (FIXME: Why):
61  /// - Nullary twines are always represented with their Kind on the left-hand
62  /// side, and the Empty kind on the right-hand side.
63  /// - Unary twines are always represented with the value on the left-hand
64  /// side, and the Empty kind on the right-hand side.
65  /// - If a Twine has another Twine as a child, that child should always be
66  /// binary (otherwise it could have been folded into the parent).
67  ///
68  /// These invariants are check by \see isValid().
69  ///
70  /// \b Efficiency Considerations
71  ///
72  /// The Twine is designed to yield efficient and small code for common
73  /// situations. For this reason, the concat() method is inlined so that
74  /// concatenations of leaf nodes can be optimized into stores directly into a
75  /// single stack allocated object.
76  ///
77  /// In practice, not all compilers can be trusted to optimize concat() fully,
78  /// so we provide two additional methods (and accompanying operator+
79  /// overloads) to guarantee that particularly important cases (cstring plus
80  /// StringRef) codegen as desired.
81  class Twine {
82  /// NodeKind - Represent the type of an argument.
83  enum NodeKind : unsigned char {
84  /// An empty string; the result of concatenating anything with it is also
85  /// empty.
86  NullKind,
87 
88  /// The empty string.
89  EmptyKind,
90 
91  /// A pointer to a Twine instance.
92  TwineKind,
93 
94  /// A pointer to a C string instance.
95  CStringKind,
96 
97  /// A pointer to an std::string instance.
98  StdStringKind,
99 
100  /// A Pointer and Length representation. Used for std::string_view,
101  /// StringRef, and SmallString. Can't use a StringRef here
102  /// because they are not trivally constructible.
103  PtrAndLengthKind,
104 
105  /// A pointer to a formatv_object_base instance.
106  FormatvObjectKind,
107 
108  /// A char value, to render as a character.
109  CharKind,
110 
111  /// An unsigned int value, to render as an unsigned decimal integer.
112  DecUIKind,
113 
114  /// An int value, to render as a signed decimal integer.
115  DecIKind,
116 
117  /// A pointer to an unsigned long value, to render as an unsigned decimal
118  /// integer.
119  DecULKind,
120 
121  /// A pointer to a long value, to render as a signed decimal integer.
122  DecLKind,
123 
124  /// A pointer to an unsigned long long value, to render as an unsigned
125  /// decimal integer.
126  DecULLKind,
127 
128  /// A pointer to a long long value, to render as a signed decimal integer.
129  DecLLKind,
130 
131  /// A pointer to a uint64_t value, to render as an unsigned hexadecimal
132  /// integer.
133  UHexKind
134  };
135 
136  union Child
137  {
138  const Twine *twine;
139  const char *cString;
140  const std::string *stdString;
141  struct {
142  const char *ptr;
143  size_t length;
144  } ptrAndLength;
145  const formatv_object_base *formatvObject;
146  char character;
147  unsigned int decUI;
148  int decI;
149  const unsigned long *decUL;
150  const long *decL;
151  const unsigned long long *decULL;
152  const long long *decLL;
153  const uint64_t *uHex;
154  };
155 
156  /// LHS - The prefix in the concatenation, which may be uninitialized for
157  /// Null or Empty kinds.
158  Child LHS;
159 
160  /// RHS - The suffix in the concatenation, which may be uninitialized for
161  /// Null or Empty kinds.
162  Child RHS;
163 
164  /// LHSKind - The NodeKind of the left hand side, \see getLHSKind().
165  NodeKind LHSKind = EmptyKind;
166 
167  /// RHSKind - The NodeKind of the right hand side, \see getRHSKind().
168  NodeKind RHSKind = EmptyKind;
169 
170  /// Construct a nullary twine; the kind must be NullKind or EmptyKind.
171  explicit Twine(NodeKind Kind) : LHSKind(Kind) {
172  assert(isNullary() && "Invalid kind!");
173  }
174 
175  /// Construct a binary twine.
176  explicit Twine(const Twine &LHS, const Twine &RHS)
177  : LHSKind(TwineKind), RHSKind(TwineKind) {
178  this->LHS.twine = &LHS;
179  this->RHS.twine = &RHS;
180  assert(isValid() && "Invalid twine!");
181  }
182 
183  /// Construct a twine from explicit values.
184  explicit Twine(Child LHS, NodeKind LHSKind, Child RHS, NodeKind RHSKind)
185  : LHS(LHS), RHS(RHS), LHSKind(LHSKind), RHSKind(RHSKind) {
186  assert(isValid() && "Invalid twine!");
187  }
188 
189  /// Check for the null twine.
190  bool isNull() const {
191  return getLHSKind() == NullKind;
192  }
193 
194  /// Check for the empty twine.
195  bool isEmpty() const {
196  return getLHSKind() == EmptyKind;
197  }
198 
199  /// Check if this is a nullary twine (null or empty).
200  bool isNullary() const {
201  return isNull() || isEmpty();
202  }
203 
204  /// Check if this is a unary twine.
205  bool isUnary() const {
206  return getRHSKind() == EmptyKind && !isNullary();
207  }
208 
209  /// Check if this is a binary twine.
210  bool isBinary() const {
211  return getLHSKind() != NullKind && getRHSKind() != EmptyKind;
212  }
213 
214  /// Check if this is a valid twine (satisfying the invariants on
215  /// order and number of arguments).
216  bool isValid() const {
217  // Nullary twines always have Empty on the RHS.
218  if (isNullary() && getRHSKind() != EmptyKind)
219  return false;
220 
221  // Null should never appear on the RHS.
222  if (getRHSKind() == NullKind)
223  return false;
224 
225  // The RHS cannot be non-empty if the LHS is empty.
226  if (getRHSKind() != EmptyKind && getLHSKind() == EmptyKind)
227  return false;
228 
229  // A twine child should always be binary.
230  if (getLHSKind() == TwineKind &&
231  !LHS.twine->isBinary())
232  return false;
233  if (getRHSKind() == TwineKind &&
234  !RHS.twine->isBinary())
235  return false;
236 
237  return true;
238  }
239 
240  /// Get the NodeKind of the left-hand side.
241  NodeKind getLHSKind() const { return LHSKind; }
242 
243  /// Get the NodeKind of the right-hand side.
244  NodeKind getRHSKind() const { return RHSKind; }
245 
246  /// Print one child from a twine.
247  void printOneChild(raw_ostream &OS, Child Ptr, NodeKind Kind) const;
248 
249  /// Print the representation of one child from a twine.
250  void printOneChildRepr(raw_ostream &OS, Child Ptr,
251  NodeKind Kind) const;
252 
253  public:
254  /// @name Constructors
255  /// @{
256 
257  /// Construct from an empty string.
258  /*implicit*/ Twine() {
259  assert(isValid() && "Invalid twine!");
260  }
261 
262  Twine(const Twine &) = default;
263 
264  /// Construct from a C string.
265  ///
266  /// We take care here to optimize "" into the empty twine -- this will be
267  /// optimized out for string constants. This allows Twine arguments have
268  /// default "" values, without introducing unnecessary string constants.
269  /*implicit*/ Twine(const char *Str) {
270  if (Str[0] != '\0') {
271  LHS.cString = Str;
272  LHSKind = CStringKind;
273  } else
274  LHSKind = EmptyKind;
275 
276  assert(isValid() && "Invalid twine!");
277  }
278  /// Delete the implicit conversion from nullptr as Twine(const char *)
279  /// cannot take nullptr.
280  /*implicit*/ Twine(std::nullptr_t) = delete;
281 
282  /// Construct from an std::string.
283  /*implicit*/ Twine(const std::string &Str) : LHSKind(StdStringKind) {
284  LHS.stdString = &Str;
285  assert(isValid() && "Invalid twine!");
286  }
287 
288  /// Construct from an std::string_view by converting it to a pointer and
289  /// length. This handles string_views on a pure API basis, and avoids
290  /// storing one (or a pointer to one) inside a Twine, which avoids problems
291  /// when mixing code compiled under various C++ standards.
292  /*implicit*/ Twine(const std::string_view &Str)
293  : LHSKind(PtrAndLengthKind) {
294  LHS.ptrAndLength.ptr = Str.data();
295  LHS.ptrAndLength.length = Str.length();
296  assert(isValid() && "Invalid twine!");
297  }
298 
299  /// Construct from a StringRef.
300  /*implicit*/ Twine(const StringRef &Str) : LHSKind(PtrAndLengthKind) {
301  LHS.ptrAndLength.ptr = Str.data();
302  LHS.ptrAndLength.length = Str.size();
303  assert(isValid() && "Invalid twine!");
304  }
305 
306  /// Construct from a SmallString.
307  /*implicit*/ Twine(const SmallVectorImpl<char> &Str)
308  : LHSKind(PtrAndLengthKind) {
309  LHS.ptrAndLength.ptr = Str.data();
310  LHS.ptrAndLength.length = Str.size();
311  assert(isValid() && "Invalid twine!");
312  }
313 
314  /// Construct from a formatv_object_base.
315  /*implicit*/ Twine(const formatv_object_base &Fmt)
316  : LHSKind(FormatvObjectKind) {
317  LHS.formatvObject = &Fmt;
318  assert(isValid() && "Invalid twine!");
319  }
320 
321  /// Construct from a char.
322  explicit Twine(char Val) : LHSKind(CharKind) {
323  LHS.character = Val;
324  }
325 
326  /// Construct from a signed char.
327  explicit Twine(signed char Val) : LHSKind(CharKind) {
328  LHS.character = static_cast<char>(Val);
329  }
330 
331  /// Construct from an unsigned char.
332  explicit Twine(unsigned char Val) : LHSKind(CharKind) {
333  LHS.character = static_cast<char>(Val);
334  }
335 
336  /// Construct a twine to print \p Val as an unsigned decimal integer.
337  explicit Twine(unsigned Val) : LHSKind(DecUIKind) {
338  LHS.decUI = Val;
339  }
340 
341  /// Construct a twine to print \p Val as a signed decimal integer.
342  explicit Twine(int Val) : LHSKind(DecIKind) {
343  LHS.decI = Val;
344  }
345 
346  /// Construct a twine to print \p Val as an unsigned decimal integer.
347  explicit Twine(const unsigned long &Val) : LHSKind(DecULKind) {
348  LHS.decUL = &Val;
349  }
350 
351  /// Construct a twine to print \p Val as a signed decimal integer.
352  explicit Twine(const long &Val) : LHSKind(DecLKind) {
353  LHS.decL = &Val;
354  }
355 
356  /// Construct a twine to print \p Val as an unsigned decimal integer.
357  explicit Twine(const unsigned long long &Val) : LHSKind(DecULLKind) {
358  LHS.decULL = &Val;
359  }
360 
361  /// Construct a twine to print \p Val as a signed decimal integer.
362  explicit Twine(const long long &Val) : LHSKind(DecLLKind) {
363  LHS.decLL = &Val;
364  }
365 
366  // FIXME: Unfortunately, to make sure this is as efficient as possible we
367  // need extra binary constructors from particular types. We can't rely on
368  // the compiler to be smart enough to fold operator+()/concat() down to the
369  // right thing. Yet.
370 
371  /// Construct as the concatenation of a C string and a StringRef.
372  /*implicit*/ Twine(const char *LHS, const StringRef &RHS)
373  : LHSKind(CStringKind), RHSKind(PtrAndLengthKind) {
374  this->LHS.cString = LHS;
375  this->RHS.ptrAndLength.ptr = RHS.data();
376  this->RHS.ptrAndLength.length = RHS.size();
377  assert(isValid() && "Invalid twine!");
378  }
379 
380  /// Construct as the concatenation of a StringRef and a C string.
381  /*implicit*/ Twine(const StringRef &LHS, const char *RHS)
382  : LHSKind(PtrAndLengthKind), RHSKind(CStringKind) {
383  this->LHS.ptrAndLength.ptr = LHS.data();
384  this->LHS.ptrAndLength.length = LHS.size();
385  this->RHS.cString = RHS;
386  assert(isValid() && "Invalid twine!");
387  }
388 
389  /// Since the intended use of twines is as temporary objects, assignments
390  /// when concatenating might cause undefined behavior or stack corruptions
391  Twine &operator=(const Twine &) = delete;
392 
393  /// Create a 'null' string, which is an empty string that always
394  /// concatenates to form another empty string.
395  static Twine createNull() {
396  return Twine(NullKind);
397  }
398 
399  /// @}
400  /// @name Numeric Conversions
401  /// @{
402 
403  // Construct a twine to print \p Val as an unsigned hexadecimal integer.
404  static Twine utohexstr(const uint64_t &Val) {
405  Child LHS, RHS;
406  LHS.uHex = &Val;
407  RHS.twine = nullptr;
408  return Twine(LHS, UHexKind, RHS, EmptyKind);
409  }
410 
411  /// @}
412  /// @name Predicate Operations
413  /// @{
414 
415  /// Check if this twine is trivially empty; a false return value does not
416  /// necessarily mean the twine is empty.
417  bool isTriviallyEmpty() const {
418  return isNullary();
419  }
420 
421  /// Return true if this twine can be dynamically accessed as a single
422  /// StringRef value with getSingleStringRef().
423  bool isSingleStringRef() const {
424  if (getRHSKind() != EmptyKind) return false;
425 
426  switch (getLHSKind()) {
427  case EmptyKind:
428  case CStringKind:
429  case StdStringKind:
430  case PtrAndLengthKind:
431  return true;
432  default:
433  return false;
434  }
435  }
436 
437  /// @}
438  /// @name String Operations
439  /// @{
440 
441  Twine concat(const Twine &Suffix) const;
442 
443  /// @}
444  /// @name Output & Conversion.
445  /// @{
446 
447  /// Return the twine contents as a std::string.
448  std::string str() const;
449 
450  /// Append the concatenated string into the given SmallString or SmallVector.
451  void toVector(SmallVectorImpl<char> &Out) const;
452 
453  /// This returns the twine as a single StringRef. This method is only valid
454  /// if isSingleStringRef() is true.
456  assert(isSingleStringRef() &&"This cannot be had as a single stringref!");
457  switch (getLHSKind()) {
458  default: llvm_unreachable("Out of sync with isSingleStringRef");
459  case EmptyKind:
460  return StringRef();
461  case CStringKind:
462  return StringRef(LHS.cString);
463  case StdStringKind:
464  return StringRef(*LHS.stdString);
465  case PtrAndLengthKind:
466  return StringRef(LHS.ptrAndLength.ptr, LHS.ptrAndLength.length);
467  }
468  }
469 
470  /// This returns the twine as a single StringRef if it can be
471  /// represented as such. Otherwise the twine is written into the given
472  /// SmallVector and a StringRef to the SmallVector's data is returned.
474  if (isSingleStringRef())
475  return getSingleStringRef();
476  toVector(Out);
477  return StringRef(Out.data(), Out.size());
478  }
479 
480  /// This returns the twine as a single null terminated StringRef if it
481  /// can be represented as such. Otherwise the twine is written into the
482  /// given SmallVector and a StringRef to the SmallVector's data is returned.
483  ///
484  /// The returned StringRef's size does not include the null terminator.
486 
487  /// Write the concatenated string represented by this twine to the
488  /// stream \p OS.
489  void print(raw_ostream &OS) const;
490 
491  /// Dump the concatenated string represented by this twine to stderr.
492  void dump() const;
493 
494  /// Write the representation of this twine to the stream \p OS.
495  void printRepr(raw_ostream &OS) const;
496 
497  /// Dump the representation of this twine to stderr.
498  void dumpRepr() const;
499 
500  /// @}
501  };
502 
503  /// @name Twine Inline Implementations
504  /// @{
505 
506  inline Twine Twine::concat(const Twine &Suffix) const {
507  // Concatenation with null is null.
508  if (isNull() || Suffix.isNull())
509  return Twine(NullKind);
510 
511  // Concatenation with empty yields the other side.
512  if (isEmpty())
513  return Suffix;
514  if (Suffix.isEmpty())
515  return *this;
516 
517  // Otherwise we need to create a new node, taking care to fold in unary
518  // twines.
519  Child NewLHS, NewRHS;
520  NewLHS.twine = this;
521  NewRHS.twine = &Suffix;
522  NodeKind NewLHSKind = TwineKind, NewRHSKind = TwineKind;
523  if (isUnary()) {
524  NewLHS = LHS;
525  NewLHSKind = getLHSKind();
526  }
527  if (Suffix.isUnary()) {
528  NewRHS = Suffix.LHS;
529  NewRHSKind = Suffix.getLHSKind();
530  }
531 
532  return Twine(NewLHS, NewLHSKind, NewRHS, NewRHSKind);
533  }
534 
535  inline Twine operator+(const Twine &LHS, const Twine &RHS) {
536  return LHS.concat(RHS);
537  }
538 
539  /// Additional overload to guarantee simplified codegen; this is equivalent to
540  /// concat().
541 
542  inline Twine operator+(const char *LHS, const StringRef &RHS) {
543  return Twine(LHS, RHS);
544  }
545 
546  /// Additional overload to guarantee simplified codegen; this is equivalent to
547  /// concat().
548 
549  inline Twine operator+(const StringRef &LHS, const char *RHS) {
550  return Twine(LHS, RHS);
551  }
552 
553  inline raw_ostream &operator<<(raw_ostream &OS, const Twine &RHS) {
554  RHS.print(OS);
555  return OS;
556  }
557 
558  /// @}
559 
560 } // end namespace llvm
561 
562 #endif // LLVM_ADT_TWINE_H
llvm
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
llvm::Twine::Twine
Twine(const long long &Val)
Construct a twine to print Val as a signed decimal integer.
Definition: Twine.h:362
llvm::Twine::getSingleStringRef
StringRef getSingleStringRef() const
This returns the twine as a single StringRef.
Definition: Twine.h:455
llvm::Twine::createNull
static Twine createNull()
Create a 'null' string, which is an empty string that always concatenates to form another empty strin...
Definition: Twine.h:395
StringRef.h
llvm::Twine::printRepr
void printRepr(raw_ostream &OS) const
Write the representation of this twine to the stream OS.
Definition: Twine.cpp:162
llvm::Twine::Twine
Twine(const StringRef &Str)
Construct from a StringRef.
Definition: Twine.h:300
llvm::Twine::Twine
Twine(const SmallVectorImpl< char > &Str)
Construct from a SmallString.
Definition: Twine.h:307
ErrorHandling.h
llvm::Twine::Twine
Twine(const std::string &Str)
Construct from an std::string.
Definition: Twine.h:283
llvm::Twine::isTriviallyEmpty
bool isTriviallyEmpty() const
Check if this twine is trivially empty; a false return value does not necessarily mean the twine is e...
Definition: Twine.h:417
RHS
Value * RHS
Definition: X86PartialReduction.cpp:76
LHS
Value * LHS
Definition: X86PartialReduction.cpp:75
llvm::Twine::Twine
Twine(const unsigned long long &Val)
Construct a twine to print Val as an unsigned decimal integer.
Definition: Twine.h:357
llvm::Twine::Twine
Twine(char Val)
Construct from a char.
Definition: Twine.h:322
llvm::raw_ostream
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
llvm::Twine::Twine
Twine(const formatv_object_base &Fmt)
Construct from a formatv_object_base.
Definition: Twine.h:315
llvm::operator<<
raw_ostream & operator<<(raw_ostream &OS, const APFixedPoint &FX)
Definition: APFixedPoint.h:230
llvm::Twine::Twine
Twine(signed char Val)
Construct from a signed char.
Definition: Twine.h:327
llvm::lltok::Kind
Kind
Definition: LLToken.h:18
llvm::Twine::str
std::string str() const
Return the twine contents as a std::string.
Definition: Twine.cpp:17
llvm::Twine::Twine
Twine(const char *LHS, const StringRef &RHS)
Construct as the concatenation of a C string and a StringRef.
Definition: Twine.h:372
llvm::Twine::utohexstr
static Twine utohexstr(const uint64_t &Val)
Definition: Twine.h:404
llvm::Twine::isSingleStringRef
bool isSingleStringRef() const
Return true if this twine can be dynamically accessed as a single StringRef value with getSingleStrin...
Definition: Twine.h:423
uint64_t
llvm::Twine::Twine
Twine(unsigned Val)
Construct a twine to print Val as an unsigned decimal integer.
Definition: Twine.h:337
llvm::Twine::toVector
void toVector(SmallVectorImpl< char > &Out) const
Append the concatenated string into the given SmallString or SmallVector.
Definition: Twine.cpp:32
llvm::Twine::toNullTerminatedStringRef
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:37
llvm::Twine::Twine
Twine(int Val)
Construct a twine to print Val as a signed decimal integer.
Definition: Twine.h:342
llvm::Value::print
void print(raw_ostream &O, bool IsForDebug=false) const
Implement operator<< on Value.
Definition: AsmWriter.cpp:4594
assert
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
llvm::Twine::dump
void dump() const
Dump the concatenated string represented by this twine to stderr.
Definition: Twine.cpp:171
Ptr
@ Ptr
Definition: TargetLibraryInfo.cpp:60
llvm::Twine::Twine
Twine(const std::string_view &Str)
Construct from an std::string_view by converting it to a pointer and length.
Definition: Twine.h:292
llvm::operator+
APInt operator+(APInt a, const APInt &b)
Definition: APInt.h:2072
llvm::Twine::Twine
Twine(const char *Str)
Construct from a C string.
Definition: Twine.h:269
llvm::StringRef
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
llvm_unreachable
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Definition: ErrorHandling.h:143
llvm::Twine::Twine
Twine(const unsigned long &Val)
Construct a twine to print Val as an unsigned decimal integer.
Definition: Twine.h:347
llvm::Twine::Twine
Twine(const StringRef &LHS, const char *RHS)
Construct as the concatenation of a StringRef and a C string.
Definition: Twine.h:381
NodeKind
Determine the kind of a node from its type.
Definition: ItaniumDemangle.h:2372
llvm::Twine
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:81
llvm::Twine::Twine
Twine(unsigned char Val)
Construct from an unsigned char.
Definition: Twine.h:332
llvm::Twine::Twine
Twine(const long &Val)
Construct a twine to print Val as a signed decimal integer.
Definition: Twine.h:352
llvm::Twine::Twine
Twine()
Construct from an empty string.
Definition: Twine.h:258
llvm::Twine::print
void print(raw_ostream &OS) const
Write the concatenated string represented by this twine to the stream OS.
Definition: Twine.cpp:157
SmallVector.h
llvm::Twine::dumpRepr
void dumpRepr() const
Dump the representation of this twine to stderr.
Definition: Twine.cpp:175
llvm::SmallVectorImpl< char >
llvm::Twine::toStringRef
StringRef toStringRef(SmallVectorImpl< char > &Out) const
This returns the twine as a single StringRef if it can be represented as such.
Definition: Twine.h:473
llvm::formatv_object_base
Definition: FormatVariadic.h:66
llvm::Twine::operator=
Twine & operator=(const Twine &)=delete
Since the intended use of twines is as temporary objects, assignments when concatenating might cause ...
llvm::Twine::concat
Twine concat(const Twine &Suffix) const
Definition: Twine.h:506