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" 21 #include "llvm/Support/FormatVariadicDetails.h" 22 #include "llvm/Support/NativeFormatting.h" 23 24 #include <type_traits> 25 #include <vector> 26 27 namespace llvm { 28 namespace detail { 29 template <typename T> 30 struct use_integral_formatter 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> 37 struct use_char_formatter 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> 47 struct use_string_formatter 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> 53 struct use_pointer_formatter 54 : public std::integral_constant<bool, std::is_pointer<T>::value && 55 !is_cstring<T>::value> {}; 56 57 template <typename T> 58 struct use_double_formatter 59 : public std::integral_constant<bool, std::is_floating_point<T>::value> {}; 60 61 class HelperFunctions { 62 protected: 63 static Optional<size_t> parseNumericPrecision(StringRef Str) { 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 78 static bool consumeHexStyle(StringRef &Str, HexPrintStyle &Style) { 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")) 87 Style = HexPrintStyle::PrefixLower; 88 else if (Str.consume_front("X+") || Str.consume_front("X")) 89 Style = HexPrintStyle::PrefixUpper; 90 return true; 91 } 92 93 static size_t consumeNumHexDigits(StringRef &Str, HexPrintStyle Style, 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> 127 struct format_provider< 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) { 133 HexPrintStyle HS; 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 } 140 141 IntegerStyle IS = IntegerStyle::Integer; 142 if (Style.consume_front("N") || Style.consume_front("n")) 143 IS = IntegerStyle::Number; 144 else if (Style.consume_front("D") || Style.consume_front("d")) 145 IS = IntegerStyle::Integer; 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> 176 struct format_provider< 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) { 182 HexPrintStyle HS = HexPrintStyle::PrefixUpper; 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> 201 struct format_provider< 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> 223 struct format_provider< 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> 289 struct format_provider< 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")) 295 S = FloatStyle::Percent; 296 else if (Style.consume_front("F") || Style.consume_front("f")) 297 S = FloatStyle::Fixed; 298 else if (Style.consume_front("E")) 299 S = FloatStyle::ExponentUpper; 300 else if (Style.consume_front("e")) 301 S = FloatStyle::Exponent; 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> 318 struct range_item_has_provider 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: 387 static_assert(detail::range_item_has_provider<IterT>::value, 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 414
