1 /* The lang_hooks data structure. 2 Copyright (C) 2001-2013 Free Software Foundation, Inc. 3 4 This file is part of GCC. 5 6 GCC is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3, or (at your option) 9 any later version. 10 11 GCC is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GCC; see the file COPYING3. If not see 18 <http://www.gnu.org/licenses/>. */ 19 20 #ifndef GCC_LANG_HOOKS_H 21 #define GCC_LANG_HOOKS_H 22 23 /* FIXME: This file should be #include-d after tree.h (for enum tree_code). */ 24 25 struct diagnostic_info; 26 27 struct gimplify_omp_ctx; 28 29 struct array_descr_info; 30 31 /* A print hook for print_tree (). */ 32 typedef void (*lang_print_tree_hook) (FILE *, tree, int indent); 33 34 enum classify_record 35 { RECORD_IS_STRUCT, RECORD_IS_CLASS, RECORD_IS_INTERFACE }; 36 37 /* The following hooks are documented in langhooks.c. Must not be 38 NULL. */ 39 40 struct lang_hooks_for_tree_inlining 41 { 42 bool (*var_mod_type_p) (tree, tree); 43 }; 44 45 /* The following hooks are used by tree-dump.c. */ 46 47 struct lang_hooks_for_tree_dump 48 { 49 /* Dump language-specific parts of tree nodes. Returns nonzero if it 50 does not want the usual dumping of the second argument. */ 51 bool (*dump_tree) (void *, tree); 52 53 /* Determine type qualifiers in a language-specific way. */ 54 int (*type_quals) (const_tree); 55 }; 56 57 /* Hooks related to types. */ 58 59 struct lang_hooks_for_types 60 { 61 /* Return a new type (with the indicated CODE), doing whatever 62 language-specific processing is required. */ 63 tree (*make_type) (enum tree_code); 64 65 /* Return what kind of RECORD_TYPE this is, mainly for purposes of 66 debug information. If not defined, record types are assumed to 67 be structures. */ 68 enum classify_record (*classify_record) (tree); 69 70 /* Given MODE and UNSIGNEDP, return a suitable type-tree with that 71 mode. */ 72 tree (*type_for_mode) (enum machine_mode, int); 73 74 /* Given PRECISION and UNSIGNEDP, return a suitable type-tree for an 75 integer type with at least that precision. */ 76 tree (*type_for_size) (unsigned, int); 77 78 /* True if the type is an instantiation of a generic type, 79 e.g. C++ template implicit specializations. */ 80 bool (*generic_p) (const_tree); 81 82 /* Returns the TREE_VEC of elements of a given generic argument pack. */ 83 tree (*get_argument_pack_elems) (const_tree); 84 85 /* Given a type, apply default promotions to unnamed function 86 arguments and return the new type. Return the same type if no 87 change. Required by any language that supports variadic 88 arguments. The default hook dies. */ 89 tree (*type_promotes_to) (tree); 90 91 /* Register TYPE as a builtin type with the indicated NAME. The 92 TYPE is placed in the outermost lexical scope. The semantics 93 should be analogous to: 94 95 typedef TYPE NAME; 96 97 in C. The default hook ignores the declaration. */ 98 void (*register_builtin_type) (tree, const char *); 99 100 /* This routine is called in tree.c to print an error message for 101 invalid use of an incomplete type. VALUE is the expression that 102 was used (or 0 if that isn't known) and TYPE is the type that was 103 invalid. */ 104 void (*incomplete_type_error) (const_tree value, const_tree type); 105 106 /* Called from assign_temp to return the maximum size, if there is one, 107 for a type. */ 108 tree (*max_size) (const_tree); 109 110 /* Register language specific type size variables as potentially OpenMP 111 firstprivate variables. */ 112 void (*omp_firstprivatize_type_sizes) (struct gimplify_omp_ctx *, tree); 113 114 /* Return TRUE if TYPE1 and TYPE2 are identical for type hashing purposes. 115 Called only after doing all language independent checks. 116 At present, this function is only called when both TYPE1 and TYPE2 are 117 FUNCTION_TYPEs. */ 118 bool (*type_hash_eq) (const_tree, const_tree); 119 120 /* Return TRUE if TYPE uses a hidden descriptor and fills in information 121 for the debugger about the array bounds, strides, etc. */ 122 bool (*get_array_descr_info) (const_tree, struct array_descr_info *); 123 124 /* Fill in information for the debugger about the bounds of TYPE. */ 125 void (*get_subrange_bounds) (const_tree, tree *, tree *); 126 127 /* A type descriptive of TYPE's complex layout generated to help the 128 debugger to decode variable-length or self-referential constructs. 129 This is only used for the AT_GNAT_descriptive_type DWARF attribute. */ 130 tree (*descriptive_type) (const_tree); 131 132 /* If we requested a pointer to a vector, build up the pointers that 133 we stripped off while looking for the inner type. Similarly for 134 return values from functions. The argument TYPE is the top of the 135 chain, and BOTTOM is the new type which we will point to. */ 136 tree (*reconstruct_complex_type) (tree, tree); 137 }; 138 139 /* Language hooks related to decls and the symbol table. */ 140 141 struct lang_hooks_for_decls 142 { 143 /* Return true if we are in the global binding level. This hook is really 144 needed only if the language supports variable-sized types at the global 145 level, i.e. declared outside subprograms. */ 146 bool (*global_bindings_p) (void); 147 148 /* Function to add a decl to the current scope level. Takes one 149 argument, a decl to add. Returns that decl, or, if the same 150 symbol is already declared, may return a different decl for that 151 name. */ 152 tree (*pushdecl) (tree); 153 154 /* Returns the chain of decls so far in the current scope level. */ 155 tree (*getdecls) (void); 156 157 /* Returns true if DECL is explicit member function. */ 158 bool (*function_decl_explicit_p) (tree); 159 160 /* Returns True if the parameter is a generic parameter decl 161 of a generic type, e.g a template template parameter for the C++ FE. */ 162 bool (*generic_generic_parameter_decl_p) (const_tree); 163 164 /* Determine if a function parameter got expanded from a 165 function parameter pack. */ 166 bool (*function_parm_expanded_from_pack_p) (tree, tree); 167 168 /* Returns the generic declaration of a generic function instantiations. */ 169 tree (*get_generic_function_decl) (const_tree); 170 171 /* Returns true when we should warn for an unused global DECL. 172 We will already have checked that it has static binding. */ 173 bool (*warn_unused_global) (const_tree); 174 175 /* Obtain a list of globals and do final output on them at end 176 of compilation */ 177 void (*final_write_globals) (void); 178 179 /* True if this decl may be called via a sibcall. */ 180 bool (*ok_for_sibcall) (const_tree); 181 182 /* True if OpenMP should privatize what this DECL points to rather 183 than the DECL itself. */ 184 bool (*omp_privatize_by_reference) (const_tree); 185 186 /* Return sharing kind if OpenMP sharing attribute of DECL is 187 predetermined, OMP_CLAUSE_DEFAULT_UNSPECIFIED otherwise. */ 188 enum omp_clause_default_kind (*omp_predetermined_sharing) (tree); 189 190 /* Return decl that should be reported for DEFAULT(NONE) failure 191 diagnostics. Usually the DECL passed in. */ 192 tree (*omp_report_decl) (tree); 193 194 /* Return true if DECL's DECL_VALUE_EXPR (if any) should be 195 disregarded in OpenMP construct, because it is going to be 196 remapped during OpenMP lowering. SHARED is true if DECL 197 is going to be shared, false if it is going to be privatized. */ 198 bool (*omp_disregard_value_expr) (tree, bool); 199 200 /* Return true if DECL that is shared iff SHARED is true should 201 be put into OMP_CLAUSE_PRIVATE_DEBUG. */ 202 bool (*omp_private_debug_clause) (tree, bool); 203 204 /* Return true if DECL in private clause needs 205 OMP_CLAUSE_PRIVATE_OUTER_REF on the private clause. */ 206 bool (*omp_private_outer_ref) (tree); 207 208 /* Build and return code for a default constructor for DECL in 209 response to CLAUSE. OUTER is corresponding outer region's 210 variable if needed. Return NULL if nothing to be done. */ 211 tree (*omp_clause_default_ctor) (tree clause, tree decl, tree outer); 212 213 /* Build and return code for a copy constructor from SRC to DST. */ 214 tree (*omp_clause_copy_ctor) (tree clause, tree dst, tree src); 215 216 /* Similarly, except use an assignment operator instead. */ 217 tree (*omp_clause_assign_op) (tree clause, tree dst, tree src); 218 219 /* Build and return code destructing DECL. Return NULL if nothing 220 to be done. */ 221 tree (*omp_clause_dtor) (tree clause, tree decl); 222 223 /* Do language specific checking on an implicitly determined clause. */ 224 void (*omp_finish_clause) (tree clause); 225 }; 226 227 /* Language hooks related to LTO serialization. */ 228 229 struct lang_hooks_for_lto 230 { 231 /* Begin a new LTO section named NAME. */ 232 void (*begin_section) (const char *name); 233 234 /* Write DATA of length LEN to the currently open LTO section. BLOCK is a 235 pointer to the dynamically allocated memory containing DATA. The 236 append_data function is responsible for freeing it when it is no longer 237 needed. */ 238 void (*append_data) (const void *data, size_t len, void *block); 239 240 /* End the previously begun LTO section. */ 241 void (*end_section) (void); 242 }; 243 244 /* Language-specific hooks. See langhooks-def.h for defaults. */ 245 246 struct lang_hooks 247 { 248 /* String identifying the front end. e.g. "GNU C++". */ 249 const char *name; 250 251 /* sizeof (struct lang_identifier), so make_node () creates 252 identifier nodes long enough for the language-specific slots. */ 253 size_t identifier_size; 254 255 /* Remove any parts of the tree that are used only by the FE. */ 256 void (*free_lang_data) (tree); 257 258 /* Determines the size of any language-specific tcc_constant or 259 tcc_exceptional nodes. Since it is called from make_node, the 260 only information available is the tree code. Expected to die 261 on unrecognized codes. */ 262 size_t (*tree_size) (enum tree_code); 263 264 /* Return the language mask used for converting argv into a sequence 265 of options. */ 266 unsigned int (*option_lang_mask) (void); 267 268 /* Initialize variables in an options structure. */ 269 void (*init_options_struct) (struct gcc_options *opts); 270 271 /* After the initialize_diagnostics hook is called, do any simple 272 initialization needed before any calls to handle_option, other 273 than that done by the init_options_struct hook. */ 274 void (*init_options) (unsigned int decoded_options_count, 275 struct cl_decoded_option *decoded_options); 276 277 /* Callback used to perform language-specific initialization for the 278 global diagnostic context structure. */ 279 void (*initialize_diagnostics) (diagnostic_context *); 280 281 /* Return true if a warning should be given about option OPTION, 282 which is for the wrong language, false if it should be quietly 283 ignored. */ 284 bool (*complain_wrong_lang_p) (const struct cl_option *option); 285 286 /* Handle the switch CODE, which has real type enum opt_code from 287 options.h. If the switch takes an argument, it is passed in ARG 288 which points to permanent storage. The handler is responsible for 289 checking whether ARG is NULL, which indicates that no argument 290 was in fact supplied. For -f and -W switches, VALUE is 1 or 0 291 for the positive and negative forms respectively. HANDLERS should 292 be passed to any recursive handle_option calls. LOC is the 293 location of the option. 294 295 Return true if the switch is valid, false if invalid. */ 296 bool (*handle_option) (size_t code, const char *arg, int value, int kind, 297 location_t loc, 298 const struct cl_option_handlers *handlers); 299 300 /* Called when all command line options have been parsed to allow 301 further processing and initialization 302 303 Should return true to indicate that a compiler back-end is 304 not required, such as with the -E option. 305 306 If errorcount is nonzero after this call the compiler exits 307 immediately and the finish hook is not called. */ 308 bool (*post_options) (const char **); 309 310 /* Called after post_options to initialize the front end. Return 311 false to indicate that no further compilation be performed, in 312 which case the finish hook is called immediately. */ 313 bool (*init) (void); 314 315 /* Called at the end of compilation, as a finalizer. */ 316 void (*finish) (void); 317 318 /* Parses the entire file. */ 319 void (*parse_file) (void); 320 321 /* Determines if it's ok for a function to have no noreturn attribute. */ 322 bool (*missing_noreturn_ok_p) (tree); 323 324 /* Called to obtain the alias set to be used for an expression or type. 325 Returns -1 if the language does nothing special for it. */ 326 alias_set_type (*get_alias_set) (tree); 327 328 /* Function to finish handling an incomplete decl at the end of 329 compilation. Default hook is does nothing. */ 330 void (*finish_incomplete_decl) (tree); 331 332 /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the 333 DECL_NODE with a newly GC-allocated copy. */ 334 void (*dup_lang_specific_decl) (tree); 335 336 /* Set the DECL_ASSEMBLER_NAME for a node. If it is the sort of 337 thing that the assembler should talk about, set 338 DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE. 339 Otherwise, set it to the ERROR_MARK_NODE to ensure that the 340 assembler does not talk about it. */ 341 void (*set_decl_assembler_name) (tree); 342 343 /* The front end can add its own statistics to -fmem-report with 344 this hook. It should output to stderr. */ 345 void (*print_statistics) (void); 346 347 /* Called by print_tree when there is a tree of class tcc_exceptional 348 that it doesn't know how to display. */ 349 lang_print_tree_hook print_xnode; 350 351 /* Called to print language-dependent parts of tcc_decl, tcc_type, 352 and IDENTIFIER_NODE nodes. */ 353 lang_print_tree_hook print_decl; 354 lang_print_tree_hook print_type; 355 lang_print_tree_hook print_identifier; 356 357 /* Computes the name to use to print a declaration. DECL is the 358 non-NULL declaration in question. VERBOSITY determines what 359 information will be printed: 0: DECL_NAME, demangled as 360 necessary. 1: and scope information. 2: and any other 361 information that might be interesting, such as function parameter 362 types in C++. The name is in the internal character set and 363 needs to be converted to the locale character set of diagnostics, 364 or to the execution character set for strings such as 365 __PRETTY_FUNCTION__. */ 366 const char *(*decl_printable_name) (tree decl, int verbosity); 367 368 /* Computes the dwarf-2/3 name for a tree. VERBOSITY determines what 369 information will be printed: 0: DECL_NAME, demangled as 370 necessary. 1: and scope information. */ 371 const char *(*dwarf_name) (tree, int verbosity); 372 373 /* This compares two types for equivalence ("compatible" in C-based languages). 374 This routine should only return 1 if it is sure. It should not be used 375 in contexts where erroneously returning 0 causes problems. */ 376 int (*types_compatible_p) (tree x, tree y); 377 378 /* Called by report_error_function to print out function name. */ 379 void (*print_error_function) (diagnostic_context *, const char *, 380 struct diagnostic_info *); 381 382 /* Convert a character from the host's to the target's character 383 set. The character should be in what C calls the "basic source 384 character set" (roughly, the set of characters defined by plain 385 old ASCII). The default is to return the character unchanged, 386 which is correct in most circumstances. Note that both argument 387 and result should be sign-extended under -fsigned-char, 388 zero-extended under -fno-signed-char. */ 389 HOST_WIDE_INT (*to_target_charset) (HOST_WIDE_INT); 390 391 /* Pointers to machine-independent attribute tables, for front ends 392 using attribs.c. If one is NULL, it is ignored. Respectively, a 393 table of attributes specific to the language, a table of 394 attributes common to two or more languages (to allow easy 395 sharing), and a table of attributes for checking formats. */ 396 const struct attribute_spec *attribute_table; 397 const struct attribute_spec *common_attribute_table; 398 const struct attribute_spec *format_attribute_table; 399 400 struct lang_hooks_for_tree_inlining tree_inlining; 401 402 struct lang_hooks_for_tree_dump tree_dump; 403 404 struct lang_hooks_for_decls decls; 405 406 struct lang_hooks_for_types types; 407 408 struct lang_hooks_for_lto lto; 409 410 /* Returns the generic parameters of an instantiation of 411 a generic type or decl, e.g. C++ template instantiation. */ 412 tree (*get_innermost_generic_parms) (const_tree); 413 414 /* Returns the TREE_VEC of arguments of an instantiation 415 of a generic type of decl, e.g. C++ template instantiation. */ 416 tree (*get_innermost_generic_args) (const_tree); 417 418 /* Determine if a tree is a function parameter pack. */ 419 bool (*function_parameter_pack_p) (const_tree); 420 421 /* Perform language-specific gimplification on the argument. Returns an 422 enum gimplify_status, though we can't see that type here. */ 423 int (*gimplify_expr) (tree *, gimple_seq *, gimple_seq *); 424 425 /* Do language specific processing in the builtin function DECL */ 426 tree (*builtin_function) (tree decl); 427 428 /* Like builtin_function, but make sure the scope is the external scope. 429 This is used to delay putting in back end builtin functions until the ISA 430 that defines the builtin is declared via function specific target options, 431 which can save memory for machines like the x86_64 that have multiple 432 ISAs. If this points to the same function as builtin_function, the 433 backend must add all of the builtins at program initialization time. */ 434 tree (*builtin_function_ext_scope) (tree decl); 435 436 /* Used to set up the tree_contains_structure array for a frontend. */ 437 void (*init_ts) (void); 438 439 /* Called by recompute_tree_invariant_for_addr_expr to go from EXPR 440 to a contained expression or DECL, possibly updating *TC or *SE 441 if in the process TREE_CONSTANT or TREE_SIDE_EFFECTS need updating. */ 442 tree (*expr_to_decl) (tree expr, bool *tc, bool *se); 443 444 /* The EH personality function decl. */ 445 tree (*eh_personality) (void); 446 447 /* Map a type to a runtime object to match type. */ 448 tree (*eh_runtime_type) (tree); 449 450 /* If non-NULL, this is a function that returns a function decl to be 451 executed if an unhandled exception is propagated out of a cleanup 452 region. For example, in C++, an exception thrown by a destructor 453 during stack unwinding is required to result in a call to 454 `std::terminate', so the C++ version of this function returns a 455 FUNCTION_DECL for `std::terminate'. */ 456 tree (*eh_protect_cleanup_actions) (void); 457 458 /* Return true if a stmt can fallthru. Used by block_may_fallthru 459 to possibly handle language trees. */ 460 bool (*block_may_fallthru) (const_tree); 461 462 /* True if this language uses __cxa_end_cleanup when the ARM EABI 463 is enabled. */ 464 bool eh_use_cxa_end_cleanup; 465 466 /* True if this language requires deep unsharing of tree nodes prior to 467 gimplification. */ 468 bool deep_unsharing; 469 470 /* Whenever you add entries here, make sure you adjust langhooks-def.h 471 and langhooks.c accordingly. */ 472 }; 473 474 /* Each front end provides its own. */ 475 extern struct lang_hooks lang_hooks; 476 477 extern tree add_builtin_function (const char *name, tree type, 478 int function_code, enum built_in_class cl, 479 const char *library_name, 480 tree attrs); 481 482 extern tree add_builtin_function_ext_scope (const char *name, tree type, 483 int function_code, 484 enum built_in_class cl, 485 const char *library_name, 486 tree attrs); 487 extern tree add_builtin_type (const char *name, tree type); 488 489 #endif /* GCC_LANG_HOOKS_H */ 490
