LLVM  14.0.0git
Twine.h
Go to the documentation of this file.
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 #if __cplusplus > 201402L
19 #include <string_view>
20 #endif
21 
22 namespace llvm {
23 
24  class formatv_object_base;
25  class raw_ostream;
26 
27  /// Twine - A lightweight data structure for efficiently representing the
28  /// concatenation of temporary values as strings.
29  ///
30  /// A Twine is a kind of rope, it represents a concatenated string using a
31  /// binary-tree, where the string is the preorder of the nodes. Since the
32  /// Twine can be efficiently rendered into a buffer when its result is used,
33  /// it avoids the cost of generating temporary values for intermediate string
34  /// results -- particularly in cases when the Twine result is never
35  /// required. By explicitly tracking the type of leaf nodes, we can also avoid
36  /// the creation of temporary strings for conversions operations (such as
37  /// appending an integer to a string).
38  ///
39  /// A Twine is not intended for use directly and should not be stored, its
40  /// implementation relies on the ability to store pointers to temporary stack
41  /// objects which may be deallocated at the end of a statement. Twines should
42  /// only be used accepted as const references in arguments, when an API wishes
43  /// to accept possibly-concatenated strings.
44  ///
45  /// Twines support a special 'null' value, which always concatenates to form
46  /// itself, and renders as an empty string. This can be returned from APIs to
47  /// effectively nullify any concatenations performed on the result.
48  ///
49  /// \b Implementation
50  ///
51  /// Given the nature of a Twine, it is not possible for the Twine's
52  /// concatenation method to construct interior nodes; the result must be
53  /// represented inside the returned value. For this reason a Twine object
54  /// actually holds two values, the left- and right-hand sides of a
55  /// concatenation. We also have nullary Twine objects, which are effectively
56  /// sentinel values that represent empty strings.
57  ///
58  /// Thus, a Twine can effectively have zero, one, or two children. The \see
59  /// isNullary(), \see isUnary(), and \see isBinary() predicates exist for
60  /// testing the number of children.
61  ///
62  /// We maintain a number of invariants on Twine objects (FIXME: Why):
63  /// - Nullary twines are always represented with their Kind on the left-hand
64  /// side, and the Empty kind on the right-hand side.
65  /// - Unary twines are always represented with the value on the left-hand
66  /// side, and the Empty kind on the right-hand side.
67  /// - If a Twine has another Twine as a child, that child should always be
68  /// binary (otherwise it could have been folded into the parent).
69  ///
70  /// These invariants are check by \see isValid().
71  ///
72  /// \b Efficiency Considerations
73  ///
74  /// The Twine is designed to yield efficient and small code for common
75  /// situations. For this reason, the concat() method is inlined so that
76  /// concatenations of leaf nodes can be optimized into stores directly into a
77  /// single stack allocated object.
78  ///
79  /// In practice, not all compilers can be trusted to optimize concat() fully,
80  /// so we provide two additional methods (and accompanying operator+
81  /// overloads) to guarantee that particularly important cases (cstring plus
82  /// StringRef) codegen as desired.
83  class Twine {
84  /// NodeKind - Represent the type of an argument.
85  enum NodeKind : unsigned char {
86  /// An empty string; the result of concatenating anything with it is also
87  /// empty.
88  NullKind,
89 
90  /// The empty string.
91  EmptyKind,
92 
93  /// A pointer to a Twine instance.
94  TwineKind,
95 
96  /// A pointer to a C string instance.
97  CStringKind,
98 
99  /// A pointer to an std::string instance.
100  StdStringKind,
101 
102  /// A Pointer and Length representation. Used for std::string_view,
103  /// StringRef, and SmallString. Can't use a StringRef here
104  /// because they are not trivally constructible.
105  PtrAndLengthKind,
106 
107  /// A pointer to a formatv_object_base instance.
108  FormatvObjectKind,
109 
110  /// A char value, to render as a character.
111  CharKind,
112 
113  /// An unsigned int value, to render as an unsigned decimal integer.
114  DecUIKind,
115 
116  /// An int value, to render as a signed decimal integer.
117  DecIKind,
118 
119  /// A pointer to an unsigned long value, to render as an unsigned decimal
120  /// integer.
121  DecULKind,
122 
123  /// A pointer to a long value, to render as a signed decimal integer.
124  DecLKind,
125 
126  /// A pointer to an unsigned long long value, to render as an unsigned
127  /// decimal integer.
128  DecULLKind,
129 
130  /// A pointer to a long long value, to render as a signed decimal integer.
131  DecLLKind,
132 
133  /// A pointer to a uint64_t value, to render as an unsigned hexadecimal
134  /// integer.
135  UHexKind
136  };
137 
138  union Child
139  {
140  const Twine *twine;
141  const char *cString;
142  const std::string *stdString;
143  struct {
144  const char *ptr;
145  size_t length;
146  } ptrAndLength;
147  const formatv_object_base *formatvObject;
148  char character;
149  unsigned int decUI;
150  int decI;
151  const unsigned long *decUL;
152  const long *decL;
153  const unsigned long long *decULL;
154  const long long *decLL;
155  const uint64_t *uHex;
156  };
157 
158  /// LHS - The prefix in the concatenation, which may be uninitialized for
159  /// Null or Empty kinds.
160  Child LHS;
161 
162  /// RHS - The suffix in the concatenation, which may be uninitialized for
163  /// Null or Empty kinds.
164  Child RHS;
165 
166  /// LHSKind - The NodeKind of the left hand side, \see getLHSKind().
167  NodeKind LHSKind = EmptyKind;
168 
169  /// RHSKind - The NodeKind of the right hand side, \see getRHSKind().
170  NodeKind RHSKind = EmptyKind;
171 
172  /// Construct a nullary twine; the kind must be NullKind or EmptyKind.
173  explicit Twine(NodeKind Kind) : LHSKind(Kind) {
174  assert(isNullary() && "Invalid kind!");
175  }
176 
177  /// Construct a binary twine.
178  explicit Twine(const Twine &LHS, const Twine &RHS)
179  : LHSKind(TwineKind), RHSKind(TwineKind) {
180  this->LHS.twine = &LHS;
181  this->RHS.twine = &RHS;
182  assert(isValid() && "Invalid twine!");
183  }
184 
185  /// Construct a twine from explicit values.
186  explicit Twine(Child LHS, NodeKind LHSKind, Child RHS, NodeKind RHSKind)
187  : LHS(LHS), RHS(RHS), LHSKind(LHSKind), RHSKind(RHSKind) {
188  assert(isValid() && "Invalid twine!");
189  }
190 
191  /// Check for the null twine.
192  bool isNull() const {
193  return getLHSKind() == NullKind;
194  }
195 
196  /// Check for the empty twine.
197  bool isEmpty() const {
198  return getLHSKind() == EmptyKind;
199  }
200 
201  /// Check if this is a nullary twine (null or empty).
202  bool isNullary() const {
203  return isNull() || isEmpty();
204  }
205 
206  /// Check if this is a unary twine.
207  bool isUnary() const {
208  return getRHSKind() == EmptyKind && !isNullary();
209  }
210 
211  /// Check if this is a binary twine.
212  bool isBinary() const {
213  return getLHSKind() != NullKind && getRHSKind() != EmptyKind;
214  }
215 
216  /// Check if this is a valid twine (satisfying the invariants on
217  /// order and number of arguments).
218  bool isValid() const {
219  // Nullary twines always have Empty on the RHS.
220  if (isNullary() && getRHSKind() != EmptyKind)
221  return false;
222 
223  // Null should never appear on the RHS.
224  if (getRHSKind() == NullKind)
225  return false;
226 
227  // The RHS cannot be non-empty if the LHS is empty.
228  if (getRHSKind() != EmptyKind && getLHSKind() == EmptyKind)
229  return false;
230 
231  // A twine child should always be binary.
232  if (getLHSKind() == TwineKind &&
233  !LHS.twine->isBinary())
234  return false;
235  if (getRHSKind() == TwineKind &&
236  !RHS.twine->isBinary())
237  return false;
238 
239  return true;
240  }
241 
242  /// Get the NodeKind of the left-hand side.
243  NodeKind getLHSKind() const { return LHSKind; }
244 
245  /// Get the NodeKind of the right-hand side.
246  NodeKind getRHSKind() const { return RHSKind; }
247 
248  /// Print one child from a twine.
249  void printOneChild(raw_ostream &OS, Child Ptr, NodeKind Kind) const;
250 
251  /// Print the representation of one child from a twine.
252  void printOneChildRepr(raw_ostream &OS, Child Ptr,
253  NodeKind Kind) const;
254 
255  public:
256  /// @name Constructors
257  /// @{
258 
259  /// Construct from an empty string.
260  /*implicit*/ Twine() {
261  assert(isValid() && "Invalid twine!");
262  }
263 
264  Twine(const Twine &) = default;
265 
266  /// Construct from a C string.
267  ///
268  /// We take care here to optimize "" into the empty twine -- this will be
269  /// optimized out for string constants. This allows Twine arguments have
270  /// default "" values, without introducing unnecessary string constants.
271  /*implicit*/ Twine(const char *Str) {
272  if (Str[0] != '\0') {
273  LHS.cString = Str;
274  LHSKind = CStringKind;
275  } else
276  LHSKind = EmptyKind;
277 
278  assert(isValid() && "Invalid twine!");
279  }
280  /// Delete the implicit conversion from nullptr as Twine(const char *)
281  /// cannot take nullptr.
282  /*implicit*/ Twine(std::nullptr_t) = delete;
283 
284  /// Construct from an std::string.
285  /*implicit*/ Twine(const std::string &Str) : LHSKind(StdStringKind) {
286  LHS.stdString = &Str;
287  assert(isValid() && "Invalid twine!");
288  }
289 
290 #if __cplusplus > 201402L
291  /// Construct from an std::string_view by converting it to a pointer and
292  /// length. This handles string_views on a pure API basis, and avoids
293  /// storing one (or a pointer to one) inside a Twine, which avoids problems
294  /// when mixing code compiled under various C++ standards.
295  /*implicit*/ Twine(const std::string_view &Str)
296  : LHSKind(PtrAndLengthKind) {
297  LHS.ptrAndLength.ptr = Str.data();
298  LHS.ptrAndLength.length = Str.length();
299  assert(isValid() && "Invalid twine!");
300  }
301 #endif
302 
303  /// Construct from a StringRef.
304  /*implicit*/ Twine(const StringRef &Str) : LHSKind(PtrAndLengthKind) {
305  LHS.ptrAndLength.ptr = Str.data();
306  LHS.ptrAndLength.length = Str.size();
307  assert(isValid() && "Invalid twine!");
308  }
309 
310  /// Construct from a SmallString.
311  /*implicit*/ Twine(const SmallVectorImpl<char> &Str)
312  : LHSKind(PtrAndLengthKind) {
313  LHS.ptrAndLength.ptr = Str.data();
314  LHS.ptrAndLength.length = Str.size();
315  assert(isValid() && "Invalid twine!");
316  }
317 
318  /// Construct from a formatv_object_base.
319  /*implicit*/ Twine(const formatv_object_base &Fmt)
320  : LHSKind(FormatvObjectKind) {
321  LHS.formatvObject = &Fmt;
322  assert(isValid() && "Invalid twine!");
323  }
324 
325  /// Construct from a char.
326  explicit Twine(char Val) : LHSKind(CharKind) {
327  LHS.character = Val;
328  }
329 
330  /// Construct from a signed char.
331  explicit Twine(signed char Val) : LHSKind(CharKind) {
332  LHS.character = static_cast<char>(Val);
333  }
334 
335  /// Construct from an unsigned char.
336  explicit Twine(unsigned char Val) : LHSKind(CharKind) {
337  LHS.character = static_cast<char>(Val);
338  }
339 
340  /// Construct a twine to print \p Val as an unsigned decimal integer.
341  explicit Twine(unsigned Val) : LHSKind(DecUIKind) {
342  LHS.decUI = Val;
343  }
344 
345  /// Construct a twine to print \p Val as a signed decimal integer.
346  explicit Twine(int Val) : LHSKind(DecIKind) {
347  LHS.decI = Val;
348  }
349 
350  /// Construct a twine to print \p Val as an unsigned decimal integer.
351  explicit Twine(const unsigned long &Val) : LHSKind(DecULKind) {
352  LHS.decUL = &Val;
353  }
354 
355  /// Construct a twine to print \p Val as a signed decimal integer.
356  explicit Twine(const long &Val) : LHSKind(DecLKind) {
357  LHS.decL = &Val;
358  }
359 
360  /// Construct a twine to print \p Val as an unsigned decimal integer.
361  explicit Twine(const unsigned long long &Val) : LHSKind(DecULLKind) {
362  LHS.decULL = &Val;
363  }
364 
365  /// Construct a twine to print \p Val as a signed decimal integer.
366  explicit Twine(const long long &Val) : LHSKind(DecLLKind) {
367  LHS.decLL = &Val;
368  }
369 
370  // FIXME: Unfortunately, to make sure this is as efficient as possible we
371  // need extra binary constructors from particular types. We can't rely on
372  // the compiler to be smart enough to fold operator+()/concat() down to the
373  // right thing. Yet.
374 
375  /// Construct as the concatenation of a C string and a StringRef.
376  /*implicit*/ Twine(const char *LHS, const StringRef &RHS)
377  : LHSKind(CStringKind), RHSKind(PtrAndLengthKind) {
378  this->LHS.cString = LHS;
379  this->RHS.ptrAndLength.ptr = RHS.data();
380  this->RHS.ptrAndLength.length = RHS.size();
381  assert(isValid() && "Invalid twine!");
382  }
383 
384  /// Construct as the concatenation of a StringRef and a C string.
385  /*implicit*/ Twine(const StringRef &LHS, const char *RHS)
386  : LHSKind(PtrAndLengthKind), RHSKind(CStringKind) {
387  this->LHS.ptrAndLength.ptr = LHS.data();
388  this->LHS.ptrAndLength.length = LHS.size();
389  this->RHS.cString = RHS;
390  assert(isValid() && "Invalid twine!");
391  }
392 
393  /// Since the intended use of twines is as temporary objects, assignments
394  /// when concatenating might cause undefined behavior or stack corruptions
395  Twine &operator=(const Twine &) = delete;
396 
397  /// Create a 'null' string, which is an empty string that always
398  /// concatenates to form another empty string.
399  static Twine createNull() {
400  return Twine(NullKind);
401  }
402 
403  /// @}
404  /// @name Numeric Conversions
405  /// @{
406 
407  // Construct a twine to print \p Val as an unsigned hexadecimal integer.
408  static Twine utohexstr(const uint64_t &Val) {
409  Child LHS, RHS;
410  LHS.uHex = &Val;
411  RHS.twine = nullptr;
412  return Twine(LHS, UHexKind, RHS, EmptyKind);
413  }
414 
415  /// @}
416  /// @name Predicate Operations
417  /// @{
418 
419  /// Check if this twine is trivially empty; a false return value does not
420  /// necessarily mean the twine is empty.
421  bool isTriviallyEmpty() const {
422  return isNullary();
423  }
424 
425  /// Return true if this twine can be dynamically accessed as a single
426  /// StringRef value with getSingleStringRef().
427  bool isSingleStringRef() const {
428  if (getRHSKind() != EmptyKind) return false;
429 
430  switch (getLHSKind()) {
431  case EmptyKind:
432  case CStringKind:
433  case StdStringKind:
434  case PtrAndLengthKind:
435  return true;
436  default:
437  return false;
438  }
439  }
440 
441  /// @}
442  /// @name String Operations
443  /// @{
444 
445  Twine concat(const Twine &Suffix) const;
446 
447  /// @}
448  /// @name Output & Conversion.
449  /// @{
450 
451  /// Return the twine contents as a std::string.
452  std::string str() const;
453 
454  /// Append the concatenated string into the given SmallString or SmallVector.
455  void toVector(SmallVectorImpl<char> &Out) const;
456 
457  /// This returns the twine as a single StringRef. This method is only valid
458  /// if isSingleStringRef() is true.
460  assert(isSingleStringRef() &&"This cannot be had as a single stringref!");
461  switch (getLHSKind()) {
462  default: llvm_unreachable("Out of sync with isSingleStringRef");
463  case EmptyKind:
464  return StringRef();
465  case CStringKind:
466  return StringRef(LHS.cString);
467  case StdStringKind:
468  return StringRef(*LHS.stdString);
469  case PtrAndLengthKind:
470  return StringRef(LHS.ptrAndLength.ptr, LHS.ptrAndLength.length);
471  }
472  }
473 
474  /// This returns the twine as a single StringRef if it can be
475  /// represented as such. Otherwise the twine is written into the given
476  /// SmallVector and a StringRef to the SmallVector's data is returned.
478  if (isSingleStringRef())
479  return getSingleStringRef();
480  toVector(Out);
481  return StringRef(Out.data(), Out.size());
482  }
483 
484  /// This returns the twine as a single null terminated StringRef if it
485  /// can be represented as such. Otherwise the twine is written into the
486  /// given SmallVector and a StringRef to the SmallVector's data is returned.
487  ///
488  /// The returned StringRef's size does not include the null terminator.
490 
491  /// Write the concatenated string represented by this twine to the
492  /// stream \p OS.
493  void print(raw_ostream &OS) const;
494 
495  /// Dump the concatenated string represented by this twine to stderr.
496  void dump() const;
497 
498  /// Write the representation of this twine to the stream \p OS.
499  void printRepr(raw_ostream &OS) const;
500 
501  /// Dump the representation of this twine to stderr.
502  void dumpRepr() const;
503 
504  /// @}
505  };
506 
507  /// @name Twine Inline Implementations
508  /// @{
509 
510  inline Twine Twine::concat(const Twine &Suffix) const {
511  // Concatenation with null is null.
512  if (isNull() || Suffix.isNull())
513  return Twine(NullKind);
514 
515  // Concatenation with empty yields the other side.
516  if (isEmpty())
517  return Suffix;
518  if (Suffix.isEmpty())
519  return *this;
520 
521  // Otherwise we need to create a new node, taking care to fold in unary
522  // twines.
523  Child NewLHS, NewRHS;
524  NewLHS.twine = this;
525  NewRHS.twine = &Suffix;
526  NodeKind NewLHSKind = TwineKind, NewRHSKind = TwineKind;
527  if (isUnary()) {
528  NewLHS = LHS;
529  NewLHSKind = getLHSKind();
530  }
531  if (Suffix.isUnary()) {
532  NewRHS = Suffix.LHS;
533  NewRHSKind = Suffix.getLHSKind();
534  }
535 
536  return Twine(NewLHS, NewLHSKind, NewRHS, NewRHSKind);
537  }
538 
539  inline Twine operator+(const Twine &LHS, const Twine &RHS) {
540  return LHS.concat(RHS);
541  }
542 
543  /// Additional overload to guarantee simplified codegen; this is equivalent to
544  /// concat().
545 
546  inline Twine operator+(const char *LHS, const StringRef &RHS) {
547  return Twine(LHS, RHS);
548  }
549 
550  /// Additional overload to guarantee simplified codegen; this is equivalent to
551  /// concat().
552 
553  inline Twine operator+(const StringRef &LHS, const char *RHS) {
554  return Twine(LHS, RHS);
555  }
556 
557  inline raw_ostream &operator<<(raw_ostream &OS, const Twine &RHS) {
558  RHS.print(OS);
559  return OS;
560  }
561 
562  /// @}
563 
564 } // end namespace llvm
565 
566 #endif // LLVM_ADT_TWINE_H
llvm
---------------------— PointerInfo ------------------------------------—
Definition: AllocatorList.h:23
llvm::Twine::Twine
Twine(const long long &Val)
Construct a twine to print Val as a signed decimal integer.
Definition: Twine.h:366
llvm::Twine::getSingleStringRef
StringRef getSingleStringRef() const
This returns the twine as a single StringRef.
Definition: Twine.h:459
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:399
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:304
llvm::Twine::Twine
Twine(const SmallVectorImpl< char > &Str)
Construct from a SmallString.
Definition: Twine.h:311
ErrorHandling.h
llvm::Twine::Twine
Twine(const std::string &Str)
Construct from an std::string.
Definition: Twine.h:285
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:421
llvm::Twine::Twine
Twine(const unsigned long long &Val)
Construct a twine to print Val as an unsigned decimal integer.
Definition: Twine.h:361
llvm::Twine::Twine
Twine(char Val)
Construct from a char.
Definition: Twine.h:326
llvm::raw_ostream
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:53
llvm::Twine::Twine
Twine(const formatv_object_base &Fmt)
Construct from a formatv_object_base.
Definition: Twine.h:319
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:331
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:376
llvm::Twine::utohexstr
static Twine utohexstr(const uint64_t &Val)
Definition: Twine.h:408
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:427
llvm::Twine::Twine
Twine(unsigned Val)
Construct a twine to print Val as an unsigned decimal integer.
Definition: Twine.h:341
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:346
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
llvm::operator+
APInt operator+(APInt a, const APInt &b)
Definition: APInt.h:2112
llvm::Twine::Twine
Twine(const char *Str)
Construct from a C string.
Definition: Twine.h:271
llvm::StringRef
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:58
llvm_unreachable
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
Definition: ErrorHandling.h:136
llvm::Twine::Twine
Twine(const unsigned long &Val)
Construct a twine to print Val as an unsigned decimal integer.
Definition: Twine.h:351
llvm::Twine::Twine
Twine(const StringRef &LHS, const char *RHS)
Construct as the concatenation of a StringRef and a C string.
Definition: Twine.h:385
NodeKind
Determine the kind of a node from its type.
Definition: ItaniumDemangle.h:2209
llvm::Twine
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:83
llvm::Twine::Twine
Twine(unsigned char Val)
Construct from an unsigned char.
Definition: Twine.h:336
llvm::Twine::Twine
Twine(const long &Val)
Construct a twine to print Val as a signed decimal integer.
Definition: Twine.h:356
llvm::Twine::Twine
Twine()
Construct from an empty string.
Definition: Twine.h:260
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::StringRef::data
const LLVM_NODISCARD char * data() const
data - Get a pointer to the start of the string (which may not be null terminated).
Definition: StringRef.h:149
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:477
llvm::formatv_object_base
Definition: FormatVariadic.h:65
llvm::StringRef::size
LLVM_NODISCARD size_t size() const
size - Get the string size.
Definition: StringRef.h:157
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:510