1 //===--- PrettyPrinter.h - Classes for aiding with AST printing -*- 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 // This file defines helper types for AST pretty-printing. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_CLANG_AST_PRETTYPRINTER_H 14 #define LLVM_CLANG_AST_PRETTYPRINTER_H 15 16 #include "clang/Basic/LLVM.h" 17 #include "clang/Basic/LangOptions.h" 18 19 namespace clang { 20 21 class DeclContext; 22 class LangOptions; 23 class Stmt; 24 25 class PrinterHelper { 26 public: 27 virtual ~PrinterHelper(); 28 virtual bool handledStmt(Stmt* E, raw_ostream& OS) = 0; 29 }; 30 31 /// Callbacks to use to customize the behavior of the pretty-printer. 32 class PrintingCallbacks { 33 protected: 34 ~PrintingCallbacks() = default; 35 36 public: 37 /// Remap a path to a form suitable for printing. remapPath(StringRef Path)38 virtual std::string remapPath(StringRef Path) const { 39 return std::string(Path); 40 } 41 42 /// When printing type to be inserted into code in specific context, this 43 /// callback can be used to avoid printing the redundant part of the 44 /// qualifier. For example, when inserting code inside namespace foo, we 45 /// should print bar::SomeType instead of foo::bar::SomeType. 46 /// To do this, shouldPrintScope should return true on "foo" NamespaceDecl. 47 /// The printing stops at the first isScopeVisible() == true, so there will 48 /// be no calls with outer scopes. isScopeVisible(const DeclContext * DC)49 virtual bool isScopeVisible(const DeclContext *DC) const { return false; } 50 }; 51 52 /// Describes how types, statements, expressions, and declarations should be 53 /// printed. 54 /// 55 /// This type is intended to be small and suitable for passing by value. 56 /// It is very frequently copied. 57 struct PrintingPolicy { 58 /// Create a default printing policy for the specified language. PrintingPolicyPrintingPolicy59 PrintingPolicy(const LangOptions &LO) 60 : Indentation(2), SuppressSpecifiers(false), 61 SuppressTagKeyword(LO.CPlusPlus), IncludeTagDefinition(false), 62 SuppressScope(false), SuppressUnwrittenScope(false), 63 SuppressInlineNamespace(true), SuppressElaboration(false), 64 SuppressInitializers(false), ConstantArraySizeAsWritten(false), 65 AnonymousTagLocations(true), SuppressStrongLifetime(false), 66 SuppressLifetimeQualifiers(false), 67 SuppressTemplateArgsInCXXConstructors(false), 68 SuppressDefaultTemplateArgs(true), Bool(LO.Bool), 69 Nullptr(LO.CPlusPlus11 || LO.C23), NullptrTypeInNamespace(LO.CPlusPlus), 70 Restrict(LO.C99), Alignof(LO.CPlusPlus11), UnderscoreAlignof(LO.C11), 71 UseVoidForZeroParams(!LO.CPlusPlus), 72 SplitTemplateClosers(!LO.CPlusPlus11), TerseOutput(false), 73 PolishForDeclaration(false), Half(LO.Half), 74 MSWChar(LO.MicrosoftExt && !LO.WChar), IncludeNewlines(true), 75 MSVCFormatting(false), ConstantsAsWritten(false), 76 SuppressImplicitBase(false), FullyQualifiedName(false), 77 PrintCanonicalTypes(false), PrintInjectedClassNameWithArguments(true), 78 UsePreferredNames(true), AlwaysIncludeTypeForTemplateArgument(false), 79 CleanUglifiedParameters(false), EntireContentsOfLargeArray(true), 80 UseEnumerators(true), UseHLSLTypes(LO.HLSL) {} 81 82 /// Adjust this printing policy for cases where it's known that we're 83 /// printing C++ code (for instance, if AST dumping reaches a C++-only 84 /// construct). This should not be used if a real LangOptions object is 85 /// available. adjustForCPlusPlusPrintingPolicy86 void adjustForCPlusPlus() { 87 SuppressTagKeyword = true; 88 Bool = true; 89 UseVoidForZeroParams = false; 90 } 91 92 /// The number of spaces to use to indent each line. 93 unsigned Indentation : 8; 94 95 /// Whether we should suppress printing of the actual specifiers for 96 /// the given type or declaration. 97 /// 98 /// This flag is only used when we are printing declarators beyond 99 /// the first declarator within a declaration group. For example, given: 100 /// 101 /// \code 102 /// const int *x, *y; 103 /// \endcode 104 /// 105 /// SuppressSpecifiers will be false when printing the 106 /// declaration for "x", so that we will print "int *x"; it will be 107 /// \c true when we print "y", so that we suppress printing the 108 /// "const int" type specifier and instead only print the "*y". 109 LLVM_PREFERRED_TYPE(bool) 110 unsigned SuppressSpecifiers : 1; 111 112 /// Whether type printing should skip printing the tag keyword. 113 /// 114 /// This is used when printing the inner type of elaborated types, 115 /// (as the tag keyword is part of the elaborated type): 116 /// 117 /// \code 118 /// struct Geometry::Point; 119 /// \endcode 120 LLVM_PREFERRED_TYPE(bool) 121 unsigned SuppressTagKeyword : 1; 122 123 /// When true, include the body of a tag definition. 124 /// 125 /// This is used to place the definition of a struct 126 /// in the middle of another declaration as with: 127 /// 128 /// \code 129 /// typedef struct { int x, y; } Point; 130 /// \endcode 131 LLVM_PREFERRED_TYPE(bool) 132 unsigned IncludeTagDefinition : 1; 133 134 /// Suppresses printing of scope specifiers. 135 LLVM_PREFERRED_TYPE(bool) 136 unsigned SuppressScope : 1; 137 138 /// Suppress printing parts of scope specifiers that are never 139 /// written, e.g., for anonymous namespaces. 140 LLVM_PREFERRED_TYPE(bool) 141 unsigned SuppressUnwrittenScope : 1; 142 143 /// Suppress printing parts of scope specifiers that correspond 144 /// to inline namespaces, where the name is unambiguous with the specifier 145 /// removed. 146 LLVM_PREFERRED_TYPE(bool) 147 unsigned SuppressInlineNamespace : 1; 148 149 /// Ignore qualifiers and tag keywords as specified by elaborated type sugar, 150 /// instead letting the underlying type print as normal. 151 LLVM_PREFERRED_TYPE(bool) 152 unsigned SuppressElaboration : 1; 153 154 /// Suppress printing of variable initializers. 155 /// 156 /// This flag is used when printing the loop variable in a for-range 157 /// statement. For example, given: 158 /// 159 /// \code 160 /// for (auto x : coll) 161 /// \endcode 162 /// 163 /// SuppressInitializers will be true when printing "auto x", so that the 164 /// internal initializer constructed for x will not be printed. 165 LLVM_PREFERRED_TYPE(bool) 166 unsigned SuppressInitializers : 1; 167 168 /// Whether we should print the sizes of constant array expressions as written 169 /// in the sources. 170 /// 171 /// This flag determines whether array types declared as 172 /// 173 /// \code 174 /// int a[4+10*10]; 175 /// char a[] = "A string"; 176 /// \endcode 177 /// 178 /// will be printed as written or as follows: 179 /// 180 /// \code 181 /// int a[104]; 182 /// char a[9] = "A string"; 183 /// \endcode 184 LLVM_PREFERRED_TYPE(bool) 185 unsigned ConstantArraySizeAsWritten : 1; 186 187 /// When printing an anonymous tag name, also print the location of that 188 /// entity (e.g., "enum <anonymous at t.h:10:5>"). Otherwise, just prints 189 /// "(anonymous)" for the name. 190 LLVM_PREFERRED_TYPE(bool) 191 unsigned AnonymousTagLocations : 1; 192 193 /// When true, suppress printing of the __strong lifetime qualifier in ARC. 194 LLVM_PREFERRED_TYPE(bool) 195 unsigned SuppressStrongLifetime : 1; 196 197 /// When true, suppress printing of lifetime qualifier in ARC. 198 LLVM_PREFERRED_TYPE(bool) 199 unsigned SuppressLifetimeQualifiers : 1; 200 201 /// When true, suppresses printing template arguments in names of C++ 202 /// constructors. 203 LLVM_PREFERRED_TYPE(bool) 204 unsigned SuppressTemplateArgsInCXXConstructors : 1; 205 206 /// When true, attempt to suppress template arguments that match the default 207 /// argument for the parameter. 208 LLVM_PREFERRED_TYPE(bool) 209 unsigned SuppressDefaultTemplateArgs : 1; 210 211 /// Whether we can use 'bool' rather than '_Bool' (even if the language 212 /// doesn't actually have 'bool', because, e.g., it is defined as a macro). 213 LLVM_PREFERRED_TYPE(bool) 214 unsigned Bool : 1; 215 216 /// Whether we should use 'nullptr' rather than '0' as a null pointer 217 /// constant. 218 LLVM_PREFERRED_TYPE(bool) 219 unsigned Nullptr : 1; 220 221 /// Whether 'nullptr_t' is in namespace 'std' or not. 222 LLVM_PREFERRED_TYPE(bool) 223 unsigned NullptrTypeInNamespace : 1; 224 225 /// Whether we can use 'restrict' rather than '__restrict'. 226 LLVM_PREFERRED_TYPE(bool) 227 unsigned Restrict : 1; 228 229 /// Whether we can use 'alignof' rather than '__alignof'. 230 LLVM_PREFERRED_TYPE(bool) 231 unsigned Alignof : 1; 232 233 /// Whether we can use '_Alignof' rather than '__alignof'. 234 LLVM_PREFERRED_TYPE(bool) 235 unsigned UnderscoreAlignof : 1; 236 237 /// Whether we should use '(void)' rather than '()' for a function prototype 238 /// with zero parameters. 239 LLVM_PREFERRED_TYPE(bool) 240 unsigned UseVoidForZeroParams : 1; 241 242 /// Whether nested templates must be closed like 'a\<b\<c\> \>' rather than 243 /// 'a\<b\<c\>\>'. 244 LLVM_PREFERRED_TYPE(bool) 245 unsigned SplitTemplateClosers : 1; 246 247 /// Provide a 'terse' output. 248 /// 249 /// For example, in this mode we don't print function bodies, class members, 250 /// declarations inside namespaces etc. Effectively, this should print 251 /// only the requested declaration. 252 LLVM_PREFERRED_TYPE(bool) 253 unsigned TerseOutput : 1; 254 255 /// When true, do certain refinement needed for producing proper declaration 256 /// tag; such as, do not print attributes attached to the declaration. 257 /// 258 LLVM_PREFERRED_TYPE(bool) 259 unsigned PolishForDeclaration : 1; 260 261 /// When true, print the half-precision floating-point type as 'half' 262 /// instead of '__fp16' 263 LLVM_PREFERRED_TYPE(bool) 264 unsigned Half : 1; 265 266 /// When true, print the built-in wchar_t type as __wchar_t. For use in 267 /// Microsoft mode when wchar_t is not available. 268 LLVM_PREFERRED_TYPE(bool) 269 unsigned MSWChar : 1; 270 271 /// When true, include newlines after statements like "break", etc. 272 LLVM_PREFERRED_TYPE(bool) 273 unsigned IncludeNewlines : 1; 274 275 /// Use whitespace and punctuation like MSVC does. In particular, this prints 276 /// anonymous namespaces as `anonymous namespace' and does not insert spaces 277 /// after template arguments. 278 LLVM_PREFERRED_TYPE(bool) 279 unsigned MSVCFormatting : 1; 280 281 /// Whether we should print the constant expressions as written in the 282 /// sources. 283 /// 284 /// This flag determines whether constants expressions like 285 /// 286 /// \code 287 /// 0x10 288 /// 2.5e3 289 /// \endcode 290 /// 291 /// will be printed as written or as follows: 292 /// 293 /// \code 294 /// 0x10 295 /// 2.5e3 296 /// \endcode 297 LLVM_PREFERRED_TYPE(bool) 298 unsigned ConstantsAsWritten : 1; 299 300 /// When true, don't print the implicit 'self' or 'this' expressions. 301 LLVM_PREFERRED_TYPE(bool) 302 unsigned SuppressImplicitBase : 1; 303 304 /// When true, print the fully qualified name of function declarations. 305 /// This is the opposite of SuppressScope and thus overrules it. 306 LLVM_PREFERRED_TYPE(bool) 307 unsigned FullyQualifiedName : 1; 308 309 /// Whether to print types as written or canonically. 310 LLVM_PREFERRED_TYPE(bool) 311 unsigned PrintCanonicalTypes : 1; 312 313 /// Whether to print an InjectedClassNameType with template arguments or as 314 /// written. When a template argument is unnamed, printing it results in 315 /// invalid C++ code. 316 LLVM_PREFERRED_TYPE(bool) 317 unsigned PrintInjectedClassNameWithArguments : 1; 318 319 /// Whether to use C++ template preferred_name attributes when printing 320 /// templates. 321 LLVM_PREFERRED_TYPE(bool) 322 unsigned UsePreferredNames : 1; 323 324 /// Whether to use type suffixes (eg: 1U) on integral non-type template 325 /// parameters. 326 LLVM_PREFERRED_TYPE(bool) 327 unsigned AlwaysIncludeTypeForTemplateArgument : 1; 328 329 /// Whether to strip underscores when printing reserved parameter names. 330 /// e.g. std::vector<class _Tp> becomes std::vector<class Tp>. 331 /// This only affects parameter names, and so describes a compatible API. 332 LLVM_PREFERRED_TYPE(bool) 333 unsigned CleanUglifiedParameters : 1; 334 335 /// Whether to print the entire array initializers, especially on non-type 336 /// template parameters, no matter how many elements there are. 337 LLVM_PREFERRED_TYPE(bool) 338 unsigned EntireContentsOfLargeArray : 1; 339 340 /// Whether to print enumerator non-type template parameters with a matching 341 /// enumerator name or via cast of an integer. 342 LLVM_PREFERRED_TYPE(bool) 343 unsigned UseEnumerators : 1; 344 345 /// Whether or not we're printing known HLSL code and should print HLSL 346 /// sugared types when possible. 347 LLVM_PREFERRED_TYPE(bool) 348 unsigned UseHLSLTypes : 1; 349 350 /// Callbacks to use to allow the behavior of printing to be customized. 351 const PrintingCallbacks *Callbacks = nullptr; 352 }; 353 354 } // end namespace clang 355 356 #endif 357