LLVM  4.0.0
FormatProviders.h
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1 //===- FormatProviders.h - Formatters for common LLVM types -----*- 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 implements format providers for many common LLVM types, for example
11 // allowing precision and width specifiers for scalar and string types.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_SUPPORT_FORMATPROVIDERS_H
16 #define LLVM_SUPPORT_FORMATPROVIDERS_H
17 
18 #include "llvm/ADT/Optional.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/StringSwitch.h"
23 
24 #include <type_traits>
25 #include <vector>
26 
27 namespace llvm {
28 namespace detail {
29 template <typename T>
31  : public std::integral_constant<
32  bool, is_one_of<T, uint8_t, int16_t, uint16_t, int32_t, uint32_t,
33  int64_t, uint64_t, int, unsigned, long, unsigned long,
34  long long, unsigned long long>::value> {};
35 
36 template <typename T>
38  : public std::integral_constant<bool, std::is_same<T, char>::value> {};
39 
40 template <typename T>
41 struct is_cstring
42  : public std::integral_constant<bool,
43  is_one_of<T, char *, const char *>::value> {
44 };
45 
46 template <typename T>
48  : public std::integral_constant<
49  bool, is_one_of<T, llvm::StringRef, std::string>::value ||
50  is_cstring<T>::value> {};
51 
52 template <typename T>
54  : public std::integral_constant<bool, std::is_pointer<T>::value &&
55  !is_cstring<T>::value> {};
56 
57 template <typename T>
59  : public std::integral_constant<bool, std::is_floating_point<T>::value> {};
60 
62 protected:
64  size_t Prec;
65  Optional<size_t> Result;
66  if (Str.empty())
67  Result = None;
68  else if (Str.getAsInteger(10, Prec)) {
69  assert(false && "Invalid precision specifier");
70  Result = None;
71  } else {
72  assert(Prec < 100 && "Precision out of range");
73  Result = std::min<size_t>(99u, Prec);
74  }
75  return Result;
76  }
77 
79  if (!Str.startswith_lower("x"))
80  return false;
81 
82  if (Str.consume_front("x-"))
83  Style = HexPrintStyle::Lower;
84  else if (Str.consume_front("X-"))
85  Style = HexPrintStyle::Upper;
86  else if (Str.consume_front("x+") || Str.consume_front("x"))
88  else if (Str.consume_front("X+") || Str.consume_front("X"))
90  return true;
91  }
92 
94  size_t Default) {
95  Str.consumeInteger(10, Default);
96  if (isPrefixedHexStyle(Style))
97  Default += 2;
98  return Default;
99  }
100 };
101 }
102 
103 /// Implementation of format_provider<T> for integral arithmetic types.
104 ///
105 /// The options string of an integral type has the grammar:
106 ///
107 /// integer_options :: [style][digits]
108 /// style :: <see table below>
109 /// digits :: <non-negative integer> 0-99
110 ///
111 /// ==========================================================================
112 /// | style | Meaning | Example | Digits Meaning |
113 /// --------------------------------------------------------------------------
114 /// | | | Input | Output | |
115 /// ==========================================================================
116 /// | x- | Hex no prefix, lower | 42 | 2a | Minimum # digits |
117 /// | X- | Hex no prefix, upper | 42 | 2A | Minimum # digits |
118 /// | x+ / x | Hex + prefix, lower | 42 | 0x2a | Minimum # digits |
119 /// | X+ / X | Hex + prefix, upper | 42 | 0x2A | Minimum # digits |
120 /// | N / n | Digit grouped number | 123456 | 123,456 | Ignored |
121 /// | D / d | Integer | 100000 | 100000 | Ignored |
122 /// | (empty) | Same as D / d | | | |
123 /// ==========================================================================
124 ///
125 
126 template <typename T>
128  T, typename std::enable_if<detail::use_integral_formatter<T>::value>::type>
129  : public detail::HelperFunctions {
130 private:
131 public:
132  static void format(const T &V, llvm::raw_ostream &Stream, StringRef Style) {
134  size_t Digits = 0;
135  if (consumeHexStyle(Style, HS)) {
136  Digits = consumeNumHexDigits(Style, HS, 0);
137  write_hex(Stream, V, HS, Digits);
138  return;
139  }
140 
142  if (Style.consume_front("N") || Style.consume_front("n"))
144  else if (Style.consume_front("D") || Style.consume_front("d"))
146 
147  Style.consumeInteger(10, Digits);
148  assert(Style.empty() && "Invalid integral format style!");
149  write_integer(Stream, V, Digits, IS);
150  }
151 };
152 
153 /// Implementation of format_provider<T> for integral pointer types.
154 ///
155 /// The options string of a pointer type has the grammar:
156 ///
157 /// pointer_options :: [style][precision]
158 /// style :: <see table below>
159 /// digits :: <non-negative integer> 0-sizeof(void*)
160 ///
161 /// ==========================================================================
162 /// | S | Meaning | Example |
163 /// --------------------------------------------------------------------------
164 /// | | | Input | Output |
165 /// ==========================================================================
166 /// | x- | Hex no prefix, lower | 0xDEADBEEF | deadbeef |
167 /// | X- | Hex no prefix, upper | 0xDEADBEEF | DEADBEEF |
168 /// | x+ / x | Hex + prefix, lower | 0xDEADBEEF | 0xdeadbeef |
169 /// | X+ / X | Hex + prefix, upper | 0xDEADBEEF | 0xDEADBEEF |
170 /// | (empty) | Same as X+ / X | | |
171 /// ==========================================================================
172 ///
173 /// The default precision is the number of nibbles in a machine word, and in all
174 /// cases indicates the minimum number of nibbles to print.
175 template <typename T>
177  T, typename std::enable_if<detail::use_pointer_formatter<T>::value>::type>
178  : public detail::HelperFunctions {
179 private:
180 public:
181  static void format(const T &V, llvm::raw_ostream &Stream, StringRef Style) {
183  consumeHexStyle(Style, HS);
184  size_t Digits = consumeNumHexDigits(Style, HS, sizeof(void *) * 2);
185  write_hex(Stream, reinterpret_cast<std::uintptr_t>(V), HS, Digits);
186  }
187 };
188 
189 /// Implementation of format_provider<T> for c-style strings and string
190 /// objects such as std::string and llvm::StringRef.
191 ///
192 /// The options string of a string type has the grammar:
193 ///
194 /// string_options :: [length]
195 ///
196 /// where `length` is an optional integer specifying the maximum number of
197 /// characters in the string to print. If `length` is omitted, the string is
198 /// printed up to the null terminator.
199 
200 template <typename T>
202  T, typename std::enable_if<detail::use_string_formatter<T>::value>::type> {
203  static void format(const T &V, llvm::raw_ostream &Stream, StringRef Style) {
204  size_t N = StringRef::npos;
205  if (!Style.empty() && Style.getAsInteger(10, N)) {
206  assert(false && "Style is not a valid integer");
207  }
208  llvm::StringRef S(V);
209  Stream << S.substr(0, N);
210  }
211 };
212 
213 /// Implementation of format_provider<T> for characters.
214 ///
215 /// The options string of a character type has the grammar:
216 ///
217 /// char_options :: (empty) | [integer_options]
218 ///
219 /// If `char_options` is empty, the character is displayed as an ASCII
220 /// character. Otherwise, it is treated as an integer options string.
221 ///
222 template <typename T>
224  T, typename std::enable_if<detail::use_char_formatter<T>::value>::type> {
225  static void format(const char &V, llvm::raw_ostream &Stream,
226  StringRef Style) {
227  if (Style.empty())
228  Stream << V;
229  else {
230  int X = static_cast<int>(V);
231  format_provider<int>::format(X, Stream, Style);
232  }
233  }
234 };
235 
236 /// Implementation of format_provider<T> for type `bool`
237 ///
238 /// The options string of a boolean type has the grammar:
239 ///
240 /// bool_options :: "" | "Y" | "y" | "D" | "d" | "T" | "t"
241 ///
242 /// ==================================
243 /// | C | Meaning |
244 /// ==================================
245 /// | Y | YES / NO |
246 /// | y | yes / no |
247 /// | D / d | Integer 0 or 1 |
248 /// | T | TRUE / FALSE |
249 /// | t | true / false |
250 /// | (empty) | Equivalent to 't' |
251 /// ==================================
252 template <> struct format_provider<bool> {
253  static void format(const bool &B, llvm::raw_ostream &Stream,
254  StringRef Style) {
255  Stream << StringSwitch<const char *>(Style)
256  .Case("Y", B ? "YES" : "NO")
257  .Case("y", B ? "yes" : "no")
258  .CaseLower("D", B ? "1" : "0")
259  .Case("T", B ? "TRUE" : "FALSE")
260  .Cases("t", "", B ? "true" : "false")
261  .Default(B ? "1" : "0");
262  }
263 };
264 
265 /// Implementation of format_provider<T> for floating point types.
266 ///
267 /// The options string of a floating point type has the format:
268 ///
269 /// float_options :: [style][precision]
270 /// style :: <see table below>
271 /// precision :: <non-negative integer> 0-99
272 ///
273 /// =====================================================
274 /// | style | Meaning | Example |
275 /// -----------------------------------------------------
276 /// | | | Input | Output |
277 /// =====================================================
278 /// | P / p | Percentage | 0.05 | 5.00% |
279 /// | F / f | Fixed point | 1.0 | 1.00 |
280 /// | E | Exponential with E | 100000 | 1.0E+05 |
281 /// | e | Exponential with e | 100000 | 1.0e+05 |
282 /// | (empty) | Same as F / f | | |
283 /// =====================================================
284 ///
285 /// The default precision is 6 for exponential (E / e) and 2 for everything
286 /// else.
287 
288 template <typename T>
290  T, typename std::enable_if<detail::use_double_formatter<T>::value>::type>
291  : public detail::HelperFunctions {
292  static void format(const T &V, llvm::raw_ostream &Stream, StringRef Style) {
293  FloatStyle S;
294  if (Style.consume_front("P") || Style.consume_front("p"))
296  else if (Style.consume_front("F") || Style.consume_front("f"))
297  S = FloatStyle::Fixed;
298  else if (Style.consume_front("E"))
300  else if (Style.consume_front("e"))
302  else
303  S = FloatStyle::Fixed;
304 
305  Optional<size_t> Precision = parseNumericPrecision(Style);
306  if (!Precision.hasValue())
307  Precision = getDefaultPrecision(S);
308 
309  write_double(Stream, static_cast<double>(V), S, Precision);
310  }
311 };
312 
313 namespace detail {
314 template <typename IterT>
315 using IterValue = typename std::iterator_traits<IterT>::value_type;
316 
317 template <typename IterT>
319  : public std::integral_constant<
320  bool, !uses_missing_provider<IterValue<IterT>>::value> {};
321 }
322 
323 /// Implementation of format_provider<T> for ranges.
324 ///
325 /// This will print an arbitrary range as a delimited sequence of items.
326 ///
327 /// The options string of a range type has the grammar:
328 ///
329 /// range_style ::= [separator] [element_style]
330 /// separator ::= "$" delimeted_expr
331 /// element_style ::= "@" delimeted_expr
332 /// delimeted_expr ::= "[" expr "]" | "(" expr ")" | "<" expr ">"
333 /// expr ::= <any string not containing delimeter>
334 ///
335 /// where the separator expression is the string to insert between consecutive
336 /// items in the range and the argument expression is the Style specification to
337 /// be used when formatting the underlying type. The default separator if
338 /// unspecified is ' ' (space). The syntax of the argument expression follows
339 /// whatever grammar is dictated by the format provider or format adapter used
340 /// to format the value type.
341 ///
342 /// Note that attempting to format an `iterator_range<T>` where no format
343 /// provider can be found for T will result in a compile error.
344 ///
345 
346 template <typename IterT> class format_provider<llvm::iterator_range<IterT>> {
347  using value = typename std::iterator_traits<IterT>::value_type;
348  using reference = typename std::iterator_traits<IterT>::reference;
349 
350  static StringRef consumeOneOption(StringRef &Style, char Indicator,
351  StringRef Default) {
352  if (Style.empty())
353  return Default;
354  if (Style.front() != Indicator)
355  return Default;
356  Style = Style.drop_front();
357  if (Style.empty()) {
358  assert(false && "Invalid range style");
359  return Default;
360  }
361 
362  std::vector<const char *> Delims = {"[]", "<>", "()"};
363  for (const char *D : Delims) {
364  if (Style.front() != D[0])
365  continue;
366  size_t End = Style.find_first_of(D[1]);
367  if (End == StringRef::npos) {
368  assert(false && "Missing range option end delimeter!");
369  return Default;
370  }
371  StringRef Result = Style.slice(1, End);
372  Style = Style.drop_front(End + 1);
373  return Result;
374  }
375  assert(false && "Invalid range style!");
376  return Default;
377  }
378 
379  static std::pair<StringRef, StringRef> parseOptions(StringRef Style) {
380  StringRef Sep = consumeOneOption(Style, '$', ", ");
381  StringRef Args = consumeOneOption(Style, '@', "");
382  assert(Style.empty() && "Unexpected text in range option string!");
383  return std::make_pair(Sep, Args);
384  }
385 
386 public:
388  "Range value_type does not have a format provider!");
389  static void format(const llvm::iterator_range<IterT> &V,
390  llvm::raw_ostream &Stream, StringRef Style) {
391  StringRef Sep;
392  StringRef ArgStyle;
393  std::tie(Sep, ArgStyle) = parseOptions(Style);
394  auto Begin = V.begin();
395  auto End = V.end();
396  if (Begin != End) {
397  auto Adapter =
398  detail::build_format_adapter(std::forward<reference>(*Begin));
399  Adapter.format(Stream, ArgStyle);
400  ++Begin;
401  }
402  while (Begin != End) {
403  Stream << Sep;
404  auto Adapter =
405  detail::build_format_adapter(std::forward<reference>(*Begin));
406  Adapter.format(Stream, ArgStyle);
407  ++Begin;
408  }
409  }
410 };
411 }
412 
413 #endif
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef drop_front(size_t N=1) const
Return a StringRef equal to 'this' but with the first N elements dropped.
Definition: StringRef.h:634
const NoneType None
Definition: None.h:23
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:494
bool hasValue() const
Definition: Optional.h:125
static void format(const bool &B, llvm::raw_ostream &Stream, StringRef Style)
static bool consumeHexStyle(StringRef &Str, HexPrintStyle &Style)
void write_double(raw_ostream &S, double D, FloatStyle Style, Optional< size_t > Precision=None)
static GCRegistry::Add< StatepointGC > D("statepoint-example","an example strategy for statepoint")
size_t getDefaultPrecision(FloatStyle Style)
LLVM_ATTRIBUTE_ALWAYS_INLINE bool consume_front(StringRef Prefix)
Returns true if this StringRef has the given prefix and removes that prefix.
Definition: StringRef.h:667
std::enable_if< std::numeric_limits< T >::is_signed, bool >::type consumeInteger(unsigned Radix, T &Result)
Parse the current string as an integer of the specified radix.
Definition: StringRef.h:528
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef slice(size_t Start, size_t End) const
Return a reference to the substring from [Start, End).
Definition: StringRef.h:699
bool isPrefixedHexStyle(HexPrintStyle S)
static GCRegistry::Add< OcamlGC > B("ocaml","ocaml 3.10-compatible GC")
LLVM_NODISCARD char front() const
front - Get the first character in the string.
Definition: StringRef.h:139
static void format(const char &V, llvm::raw_ostream &Stream, StringRef Style)
format_object< Ts...> format(const char *Fmt, const Ts &...Vals)
These are helper functions used to produce formatted output.
Definition: Format.h:124
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE StringRef substr(size_t Start, size_t N=npos) const
Return a reference to the substring from [Start, Start + N).
Definition: StringRef.h:587
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang","erlang-compatible garbage collector")
static const unsigned End
static void format(const llvm::iterator_range< IterT > &V, llvm::raw_ostream &Stream, StringRef Style)
IteratorT end() const
IteratorT begin() const
A range adaptor for a pair of iterators.
LLVM_NODISCARD LLVM_ATTRIBUTE_ALWAYS_INLINE bool empty() const
empty - Check if the string is empty.
Definition: StringRef.h:130
typename std::iterator_traits< IterT >::value_type IterValue
void write_hex(raw_ostream &S, uint64_t N, HexPrintStyle Style, Optional< size_t > Width=None)
static const size_t npos
Definition: StringRef.h:51
#define N
LLVM_NODISCARD size_t find_first_of(char C, size_t From=0) const
Find the first character in the string that is C, or npos if not found.
Definition: StringRef.h:392
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
std::enable_if< uses_format_member< T >::value, T >::type build_format_adapter(T &&Item)
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:44
static Optional< size_t > parseNumericPrecision(StringRef Str)
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:47
LLVM_NODISCARD bool startswith_lower(StringRef Prefix) const
Check if this string starts with the given Prefix, ignoring case.
Definition: StringRef.cpp:61
void write_integer(raw_ostream &S, unsigned int N, size_t MinDigits, IntegerStyle Style)
static size_t consumeNumHexDigits(StringRef &Str, HexPrintStyle Style, size_t Default)