1 /* The lang_hooks data structure. 2 Copyright 2001, 2002, 2003, 2004, 2005, 2006 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 2, 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 COPYING. If not, write to 18 the Free Software Foundation, 51 Franklin Street, Fifth Floor, 19 Boston, MA 02110-1301, USA. */ 20 21 #ifndef GCC_LANG_HOOKS_H 22 #define GCC_LANG_HOOKS_H 23 24 /* This file should be #include-d after tree.h. */ 25 26 struct diagnostic_context; 27 28 struct gimplify_omp_ctx; 29 30 /* A print hook for print_tree (). */ 31 typedef void (*lang_print_tree_hook) (FILE *, tree, int indent); 32 33 /* The following hooks are documented in langhooks.c. Must not be 34 NULL. */ 35 36 struct lang_hooks_for_tree_inlining 37 { 38 tree (*walk_subtrees) (tree *, int *, 39 tree (*) (tree *, int *, void *), 40 void *, struct pointer_set_t*); 41 int (*cannot_inline_tree_fn) (tree *); 42 int (*disregard_inline_limits) (tree); 43 tree (*add_pending_fn_decls) (void *, tree); 44 int (*auto_var_in_fn_p) (tree, tree); 45 int (*anon_aggr_type_p) (tree); 46 bool (*var_mod_type_p) (tree, tree); 47 int (*start_inlining) (tree); 48 void (*end_inlining) (tree); 49 tree (*convert_parm_for_inlining) (tree, tree, tree, int); 50 }; 51 52 struct lang_hooks_for_callgraph 53 { 54 /* The node passed is a language-specific tree node. If its contents 55 are relevant to use of other declarations, mark them. */ 56 tree (*analyze_expr) (tree *, int *, tree); 57 58 /* Produce RTL for function passed as argument. */ 59 void (*expand_function) (tree); 60 }; 61 62 /* Lang hooks for management of language-specific data or status 63 when entering / leaving functions etc. */ 64 struct lang_hooks_for_functions 65 { 66 /* Called when entering a function. */ 67 void (*init) (struct function *); 68 69 /* Called when leaving a function. */ 70 void (*final) (struct function *); 71 72 /* Called when entering a nested function. */ 73 void (*enter_nested) (struct function *); 74 75 /* Called when leaving a nested function. */ 76 void (*leave_nested) (struct function *); 77 78 /* Determines if it's ok for a function to have no noreturn attribute. */ 79 bool (*missing_noreturn_ok_p) (tree); 80 }; 81 82 /* The following hooks are used by tree-dump.c. */ 83 84 struct lang_hooks_for_tree_dump 85 { 86 /* Dump language-specific parts of tree nodes. Returns nonzero if it 87 does not want the usual dumping of the second argument. */ 88 bool (*dump_tree) (void *, tree); 89 90 /* Determine type qualifiers in a language-specific way. */ 91 int (*type_quals) (tree); 92 }; 93 94 /* Hooks related to types. */ 95 96 struct lang_hooks_for_types 97 { 98 /* Return a new type (with the indicated CODE), doing whatever 99 language-specific processing is required. */ 100 tree (*make_type) (enum tree_code); 101 102 /* Given MODE and UNSIGNEDP, return a suitable type-tree with that 103 mode. */ 104 tree (*type_for_mode) (enum machine_mode, int); 105 106 /* Given PRECISION and UNSIGNEDP, return a suitable type-tree for an 107 integer type with at least that precision. */ 108 tree (*type_for_size) (unsigned, int); 109 110 /* Given an integer type T, return a type like T but unsigned. 111 If T is unsigned, the value is T. */ 112 tree (*unsigned_type) (tree); 113 114 /* Given an integer type T, return a type like T but signed. 115 If T is signed, the value is T. */ 116 tree (*signed_type) (tree); 117 118 /* Return a type the same as TYPE except unsigned or signed 119 according to UNSIGNEDP. */ 120 tree (*signed_or_unsigned_type) (int, tree); 121 122 /* Given a type, apply default promotions to unnamed function 123 arguments and return the new type. Return the same type if no 124 change. Required by any language that supports variadic 125 arguments. The default hook dies. */ 126 tree (*type_promotes_to) (tree); 127 128 /* Register TYPE as a builtin type with the indicated NAME. The 129 TYPE is placed in the outermost lexical scope. The semantics 130 should be analogous to: 131 132 typedef TYPE NAME; 133 134 in C. The default hook ignores the declaration. */ 135 void (*register_builtin_type) (tree, const char *); 136 137 /* This routine is called in tree.c to print an error message for 138 invalid use of an incomplete type. VALUE is the expression that 139 was used (or 0 if that isn't known) and TYPE is the type that was 140 invalid. */ 141 void (*incomplete_type_error) (tree value, tree type); 142 143 /* Called from assign_temp to return the maximum size, if there is one, 144 for a type. */ 145 tree (*max_size) (tree); 146 147 /* Register language specific type size variables as potentially OpenMP 148 firstprivate variables. */ 149 void (*omp_firstprivatize_type_sizes) (struct gimplify_omp_ctx *, tree); 150 151 /* Nonzero if types that are identical are to be hashed so that only 152 one copy is kept. If a language requires unique types for each 153 user-specified type, such as Ada, this should be set to TRUE. */ 154 bool hash_types; 155 }; 156 157 /* Language hooks related to decls and the symbol table. */ 158 159 struct lang_hooks_for_decls 160 { 161 /* Returns nonzero if we are in the global binding level. Ada 162 returns -1 for an undocumented reason used in stor-layout.c. */ 163 int (*global_bindings_p) (void); 164 165 /* Insert BLOCK at the end of the list of subblocks of the 166 current binding level. This is used when a BIND_EXPR is expanded, 167 to handle the BLOCK node inside the BIND_EXPR. */ 168 void (*insert_block) (tree); 169 170 /* Function to add a decl to the current scope level. Takes one 171 argument, a decl to add. Returns that decl, or, if the same 172 symbol is already declared, may return a different decl for that 173 name. */ 174 tree (*pushdecl) (tree); 175 176 /* Returns the chain of decls so far in the current scope level. */ 177 tree (*getdecls) (void); 178 179 /* Returns true when we should warn for an unused global DECL. 180 We will already have checked that it has static binding. */ 181 bool (*warn_unused_global) (tree); 182 183 /* Obtain a list of globals and do final output on them at end 184 of compilation */ 185 void (*final_write_globals) (void); 186 187 /* Do necessary preparations before assemble_variable can proceed. */ 188 void (*prepare_assemble_variable) (tree); 189 190 /* True if this decl may be called via a sibcall. */ 191 bool (*ok_for_sibcall) (tree); 192 193 /* Return the COMDAT group into which this DECL should be placed. 194 It is known that the DECL belongs in *some* COMDAT group when 195 this hook is called. The return value will be used immediately, 196 but not explicitly deallocated, so implementations should not use 197 xmalloc to allocate the string returned. (Typically, the return 198 value will be the string already stored in an 199 IDENTIFIER_NODE.) */ 200 const char * (*comdat_group) (tree); 201 202 /* True if OpenMP should privatize what this DECL points to rather 203 than the DECL itself. */ 204 bool (*omp_privatize_by_reference) (tree); 205 206 /* Return sharing kind if OpenMP sharing attribute of DECL is 207 predetermined, OMP_CLAUSE_DEFAULT_UNSPECIFIED otherwise. */ 208 enum omp_clause_default_kind (*omp_predetermined_sharing) (tree); 209 210 /* Return true if DECL's DECL_VALUE_EXPR (if any) should be 211 disregarded in OpenMP construct, because it is going to be 212 remapped during OpenMP lowering. SHARED is true if DECL 213 is going to be shared, false if it is going to be privatized. */ 214 bool (*omp_disregard_value_expr) (tree, bool); 215 216 /* Return true if DECL that is shared iff SHARED is true should 217 be put into OMP_CLAUSE_PRIVATE_DEBUG. */ 218 bool (*omp_private_debug_clause) (tree, bool); 219 220 /* Build and return code for a default constructor for DECL in 221 response to CLAUSE. Return NULL if nothing to be done. */ 222 tree (*omp_clause_default_ctor) (tree clause, tree decl); 223 224 /* Build and return code for a copy constructor from SRC to DST. */ 225 tree (*omp_clause_copy_ctor) (tree clause, tree dst, tree src); 226 227 /* Similarly, except use an assignment operator instead. */ 228 tree (*omp_clause_assign_op) (tree clause, tree dst, tree src); 229 230 /* Build and return code destructing DECL. Return NULL if nothing 231 to be done. */ 232 tree (*omp_clause_dtor) (tree clause, tree decl); 233 }; 234 235 /* Language-specific hooks. See langhooks-def.h for defaults. */ 236 237 struct lang_hooks 238 { 239 /* String identifying the front end. e.g. "GNU C++". */ 240 const char *name; 241 242 /* sizeof (struct lang_identifier), so make_node () creates 243 identifier nodes long enough for the language-specific slots. */ 244 size_t identifier_size; 245 246 /* Determines the size of any language-specific tcc_constant or 247 tcc_exceptional nodes. Since it is called from make_node, the 248 only information available is the tree code. Expected to die 249 on unrecognized codes. */ 250 size_t (*tree_size) (enum tree_code); 251 252 /* The first callback made to the front end, for simple 253 initialization needed before any calls to handle_option. Return 254 the language mask to filter the switch array with. */ 255 unsigned int (*init_options) (unsigned int argc, const char **argv); 256 257 /* Callback used to perform language-specific initialization for the 258 global diagnostic context structure. */ 259 void (*initialize_diagnostics) (struct diagnostic_context *); 260 261 /* Handle the switch CODE, which has real type enum opt_code from 262 options.h. If the switch takes an argument, it is passed in ARG 263 which points to permanent storage. The handler is responsible for 264 checking whether ARG is NULL, which indicates that no argument 265 was in fact supplied. For -f and -W switches, VALUE is 1 or 0 266 for the positive and negative forms respectively. 267 268 Return 1 if the switch is valid, 0 if invalid, and -1 if it's 269 valid and should not be treated as language-independent too. */ 270 int (*handle_option) (size_t code, const char *arg, int value); 271 272 /* Return false to use the default complaint about a missing 273 argument, otherwise output a complaint and return true. */ 274 bool (*missing_argument) (const char *opt, size_t code); 275 276 /* Called when all command line options have been parsed to allow 277 further processing and initialization 278 279 Should return true to indicate that a compiler back-end is 280 not required, such as with the -E option. 281 282 If errorcount is nonzero after this call the compiler exits 283 immediately and the finish hook is not called. */ 284 bool (*post_options) (const char **); 285 286 /* Called after post_options to initialize the front end. Return 287 false to indicate that no further compilation be performed, in 288 which case the finish hook is called immediately. */ 289 bool (*init) (void); 290 291 /* Called at the end of compilation, as a finalizer. */ 292 void (*finish) (void); 293 294 /* Parses the entire file. The argument is nonzero to cause bison 295 parsers to dump debugging information during parsing. */ 296 void (*parse_file) (int); 297 298 /* Called immediately after parsing to clear the binding stack. */ 299 void (*clear_binding_stack) (void); 300 301 /* Called to obtain the alias set to be used for an expression or type. 302 Returns -1 if the language does nothing special for it. */ 303 HOST_WIDE_INT (*get_alias_set) (tree); 304 305 /* Called with an expression that is to be processed as a constant. 306 Returns either the same expression or a language-independent 307 constant equivalent to its input. */ 308 tree (*expand_constant) (tree); 309 310 /* Called by expand_expr for language-specific tree codes. 311 Fourth argument is actually an enum expand_modifier. */ 312 rtx (*expand_expr) (tree, rtx, enum machine_mode, int, rtx *); 313 314 /* Called by expand_expr to generate the definition of a decl. Returns 315 1 if handled, 0 otherwise. */ 316 int (*expand_decl) (tree); 317 318 /* Hook called by safe_from_p for language-specific tree codes. It is 319 up to the language front-end to install a hook if it has any such 320 codes that safe_from_p needs to know about. Since same_from_p will 321 recursively explore the TREE_OPERANDs of an expression, this hook 322 should not reexamine those pieces. This routine may recursively 323 call safe_from_p; it should always pass `0' as the TOP_P 324 parameter. */ 325 int (*safe_from_p) (rtx, tree); 326 327 /* Function to finish handling an incomplete decl at the end of 328 compilation. Default hook is does nothing. */ 329 void (*finish_incomplete_decl) (tree); 330 331 /* Mark EXP saying that we need to be able to take the address of 332 it; it should not be allocated in a register. Return true if 333 successful. */ 334 bool (*mark_addressable) (tree); 335 336 /* Hook called by staticp for language-specific tree codes. */ 337 tree (*staticp) (tree); 338 339 /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the 340 DECL_NODE with a newly GC-allocated copy. */ 341 void (*dup_lang_specific_decl) (tree); 342 343 /* Set the DECL_ASSEMBLER_NAME for a node. If it is the sort of 344 thing that the assembler should talk about, set 345 DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE. 346 Otherwise, set it to the ERROR_MARK_NODE to ensure that the 347 assembler does not talk about it. */ 348 void (*set_decl_assembler_name) (tree); 349 350 /* Return nonzero if fold-const is free to use bit-field 351 optimizations, for instance in fold_truthop(). */ 352 bool (*can_use_bit_fields_p) (void); 353 354 /* Nonzero if operations on types narrower than their mode should 355 have their results reduced to the precision of the type. */ 356 bool reduce_bit_field_operations; 357 358 /* Nonzero if this front end does not generate a dummy BLOCK between 359 the outermost scope of the function and the FUNCTION_DECL. See 360 is_body_block in stmt.c, and its callers. */ 361 bool no_body_blocks; 362 363 /* The front end can add its own statistics to -fmem-report with 364 this hook. It should output to stderr. */ 365 void (*print_statistics) (void); 366 367 /* Called by print_tree when there is a tree of class tcc_exceptional 368 that it doesn't know how to display. */ 369 lang_print_tree_hook print_xnode; 370 371 /* Called to print language-dependent parts of tcc_decl, tcc_type, 372 and IDENTIFIER_NODE nodes. */ 373 lang_print_tree_hook print_decl; 374 lang_print_tree_hook print_type; 375 lang_print_tree_hook print_identifier; 376 377 /* Computes the name to use to print a declaration. DECL is the 378 non-NULL declaration in question. VERBOSITY determines what 379 information will be printed: 0: DECL_NAME, demangled as 380 necessary. 1: and scope information. 2: and any other 381 information that might be interesting, such as function parameter 382 types in C++. */ 383 const char *(*decl_printable_name) (tree decl, int verbosity); 384 385 /* Computes the dwarf-2/3 name for a tree. VERBOSITY determines what 386 information will be printed: 0: DECL_NAME, demangled as 387 necessary. 1: and scope information. */ 388 const char *(*dwarf_name) (tree, int verbosity); 389 390 /* This compares two types for equivalence ("compatible" in C-based languages). 391 This routine should only return 1 if it is sure. It should not be used 392 in contexts where erroneously returning 0 causes problems. */ 393 int (*types_compatible_p) (tree x, tree y); 394 395 /* Given a CALL_EXPR, return a function decl that is its target. */ 396 tree (*lang_get_callee_fndecl) (tree); 397 398 /* Called by report_error_function to print out function name. */ 399 void (*print_error_function) (struct diagnostic_context *, const char *); 400 401 /* Called from expr_size to calculate the size of the value of an 402 expression in a language-dependent way. Returns a tree for the size 403 in bytes. A frontend can call lhd_expr_size to get the default 404 semantics in cases that it doesn't want to handle specially. */ 405 tree (*expr_size) (tree); 406 407 /* Convert a character from the host's to the target's character 408 set. The character should be in what C calls the "basic source 409 character set" (roughly, the set of characters defined by plain 410 old ASCII). The default is to return the character unchanged, 411 which is correct in most circumstances. Note that both argument 412 and result should be sign-extended under -fsigned-char, 413 zero-extended under -fno-signed-char. */ 414 HOST_WIDE_INT (*to_target_charset) (HOST_WIDE_INT); 415 416 /* Pointers to machine-independent attribute tables, for front ends 417 using attribs.c. If one is NULL, it is ignored. Respectively, a 418 table of attributes specific to the language, a table of 419 attributes common to two or more languages (to allow easy 420 sharing), and a table of attributes for checking formats. */ 421 const struct attribute_spec *attribute_table; 422 const struct attribute_spec *common_attribute_table; 423 const struct attribute_spec *format_attribute_table; 424 425 /* Function-related language hooks. */ 426 struct lang_hooks_for_functions function; 427 428 struct lang_hooks_for_tree_inlining tree_inlining; 429 430 struct lang_hooks_for_callgraph callgraph; 431 432 struct lang_hooks_for_tree_dump tree_dump; 433 434 struct lang_hooks_for_decls decls; 435 436 struct lang_hooks_for_types types; 437 438 /* Perform language-specific gimplification on the argument. Returns an 439 enum gimplify_status, though we can't see that type here. */ 440 int (*gimplify_expr) (tree *, tree *, tree *); 441 442 /* Fold an OBJ_TYPE_REF expression to the address of a function. 443 KNOWN_TYPE carries the true type of the OBJ_TYPE_REF_OBJECT. */ 444 tree (*fold_obj_type_ref) (tree, tree); 445 446 /* Return a definition for a builtin function named NAME and whose data type 447 is TYPE. TYPE should be a function type with argument types. 448 FUNCTION_CODE tells later passes how to compile calls to this function. 449 See tree.h for its possible values. 450 451 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME, 452 the name to be called if we can't opencode the function. If 453 ATTRS is nonzero, use that for the function's attribute list. */ 454 tree (*builtin_function) (const char *name, tree type, int function_code, 455 enum built_in_class bt_class, 456 const char *library_name, tree attrs); 457 458 /* Used to set up the tree_contains_structure array for a frontend. */ 459 void (*init_ts) (void); 460 461 /* Called by recompute_tree_invariant_for_addr_expr to go from EXPR 462 to a contained expression or DECL, possibly updating *TC, *TI or 463 *SE if in the process TREE_CONSTANT, TREE_INVARIANT or 464 TREE_SIDE_EFFECTS need updating. */ 465 tree (*expr_to_decl) (tree expr, bool *tc, bool *ti, bool *se); 466 467 /* Whenever you add entries here, make sure you adjust langhooks-def.h 468 and langhooks.c accordingly. */ 469 }; 470 471 /* Each front end provides its own. */ 472 extern const struct lang_hooks lang_hooks; 473 474 #endif /* GCC_LANG_HOOKS_H */ 475