1 /* The lang_hooks data structure.
2 Copyright (C) 2001-2016 Free Software Foundation, Inc.
4 This file is part of GCC.
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)
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.
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/>. */
20 #ifndef GCC_LANG_HOOKS_H
21 #define GCC_LANG_HOOKS_H
23 /* FIXME: This file should be #include-d after tree.h (for enum tree_code). */
25 struct diagnostic_info;
27 struct gimplify_omp_ctx;
29 struct array_descr_info;
31 /* A print hook for print_tree (). */
32 typedef void (*lang_print_tree_hook) (FILE *, tree, int indent);
35 { RECORD_IS_STRUCT, RECORD_IS_CLASS, RECORD_IS_INTERFACE };
37 /* The following hooks are documented in langhooks.c. Must not be
40 struct lang_hooks_for_tree_inlining
42 bool (*var_mod_type_p) (tree, tree);
45 /* The following hooks are used by tree-dump.c. */
47 struct lang_hooks_for_tree_dump
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);
53 /* Determine type qualifiers in a language-specific way. */
54 int (*type_quals) (const_tree);
57 /* Hooks related to types. */
59 struct lang_hooks_for_types
61 /* Return a new type (with the indicated CODE), doing whatever
62 language-specific processing is required. */
63 tree (*make_type) (enum tree_code);
65 /* Return what kind of RECORD_TYPE this is, mainly for purposes of
66 debug information. If not defined, record types are assumed to
68 enum classify_record (*classify_record) (tree);
70 /* Given MODE and UNSIGNEDP, return a suitable type-tree with that
72 tree (*type_for_mode) (machine_mode, int);
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);
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);
82 /* Returns the TREE_VEC of elements of a given generic argument pack. */
83 tree (*get_argument_pack_elems) (const_tree);
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);
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:
97 in C. The default hook ignores the declaration. */
98 void (*register_builtin_type) (tree, const char *);
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
104 void (*incomplete_type_error) (const_tree value, const_tree type);
106 /* Called from assign_temp to return the maximum size, if there is one,
108 tree (*max_size) (const_tree);
110 /* Register language specific type size variables as potentially OpenMP
111 firstprivate variables. */
112 void (*omp_firstprivatize_type_sizes) (struct gimplify_omp_ctx *, tree);
114 /* Return true if TYPE is a mappable type. */
115 bool (*omp_mappable_type) (tree type);
117 /* Return TRUE if TYPE1 and TYPE2 are identical for type hashing purposes.
118 Called only after doing all language independent checks.
119 At present, this function is only called when both TYPE1 and TYPE2 are
121 bool (*type_hash_eq) (const_tree, const_tree);
123 /* Return TRUE if TYPE uses a hidden descriptor and fills in information
124 for the debugger about the array bounds, strides, etc. */
125 bool (*get_array_descr_info) (const_tree, struct array_descr_info *);
127 /* Fill in information for the debugger about the bounds of TYPE. */
128 void (*get_subrange_bounds) (const_tree, tree *, tree *);
130 /* Called on INTEGER_TYPEs. Return NULL_TREE for non-biased types. For
131 biased types, return as an INTEGER_CST node the value that is represented
132 by a physical zero. */
133 tree (*get_type_bias) (const_tree);
135 /* A type descriptive of TYPE's complex layout generated to help the
136 debugger to decode variable-length or self-referential constructs.
137 This is only used for the AT_GNAT_descriptive_type DWARF attribute. */
138 tree (*descriptive_type) (const_tree);
140 /* If we requested a pointer to a vector, build up the pointers that
141 we stripped off while looking for the inner type. Similarly for
142 return values from functions. The argument TYPE is the top of the
143 chain, and BOTTOM is the new type which we will point to. */
144 tree (*reconstruct_complex_type) (tree, tree);
146 /* Returns the tree that represents the underlying data type used to
147 implement the enumeration. The default implementation will just use
148 type_for_size. Used in dwarf2out.c to add a DW_AT_type base type
149 reference to a DW_TAG_enumeration. */
150 tree (*enum_underlying_base_type) (const_tree);
152 /* Return a type to use in the debug info instead of TYPE, or NULL_TREE to
153 keep TYPE. This is useful to keep a single "source type" when the
154 middle-end uses specialized types, for instance constrained discriminated
156 tree (*get_debug_type) (const_tree);
158 /* Return TRUE if TYPE implements a fixed point type and fills in information
159 for the debugger about scale factor, etc. */
160 bool (*get_fixed_point_type_info) (const_tree,
161 struct fixed_point_type_info *);
164 /* Language hooks related to decls and the symbol table. */
166 struct lang_hooks_for_decls
168 /* Return true if we are in the global binding level. This hook is really
169 needed only if the language supports variable-sized types at the global
170 level, i.e. declared outside subprograms. */
171 bool (*global_bindings_p) (void);
173 /* Function to add a decl to the current scope level. Takes one
174 argument, a decl to add. Returns that decl, or, if the same
175 symbol is already declared, may return a different decl for that
177 tree (*pushdecl) (tree);
179 /* Returns the chain of decls so far in the current scope level. */
180 tree (*getdecls) (void);
182 /* Returns true if DECL is explicit member function. */
183 bool (*function_decl_explicit_p) (tree);
185 /* Returns true if DECL is C++11 deleted special member function. */
186 bool (*function_decl_deleted_p) (tree);
188 /* Returns True if the parameter is a generic parameter decl
189 of a generic type, e.g a template template parameter for the C++ FE. */
190 bool (*generic_generic_parameter_decl_p) (const_tree);
192 /* Determine if a function parameter got expanded from a
193 function parameter pack. */
194 bool (*function_parm_expanded_from_pack_p) (tree, tree);
196 /* Returns the generic declaration of a generic function instantiations. */
197 tree (*get_generic_function_decl) (const_tree);
199 /* Returns true when we should warn for an unused global DECL.
200 We will already have checked that it has static binding. */
201 bool (*warn_unused_global) (const_tree);
203 /* Perform any post compilation-proper parser cleanups and
204 processing. This is currently only needed for the C++ parser,
205 which hopefully can be cleaned up so this hook is no longer
207 void (*post_compilation_parsing_cleanups) (void);
209 /* True if this decl may be called via a sibcall. */
210 bool (*ok_for_sibcall) (const_tree);
212 /* True if OpenMP should privatize what this DECL points to rather
213 than the DECL itself. */
214 bool (*omp_privatize_by_reference) (const_tree);
216 /* Return sharing kind if OpenMP sharing attribute of DECL is
217 predetermined, OMP_CLAUSE_DEFAULT_UNSPECIFIED otherwise. */
218 enum omp_clause_default_kind (*omp_predetermined_sharing) (tree);
220 /* Return decl that should be reported for DEFAULT(NONE) failure
221 diagnostics. Usually the DECL passed in. */
222 tree (*omp_report_decl) (tree);
224 /* Return true if DECL's DECL_VALUE_EXPR (if any) should be
225 disregarded in OpenMP construct, because it is going to be
226 remapped during OpenMP lowering. SHARED is true if DECL
227 is going to be shared, false if it is going to be privatized. */
228 bool (*omp_disregard_value_expr) (tree, bool);
230 /* Return true if DECL that is shared iff SHARED is true should
231 be put into OMP_CLAUSE_PRIVATE_DEBUG. */
232 bool (*omp_private_debug_clause) (tree, bool);
234 /* Return true if DECL in private clause needs
235 OMP_CLAUSE_PRIVATE_OUTER_REF on the private clause. */
236 bool (*omp_private_outer_ref) (tree);
238 /* Build and return code for a default constructor for DECL in
239 response to CLAUSE. OUTER is corresponding outer region's
240 variable if needed. Return NULL if nothing to be done. */
241 tree (*omp_clause_default_ctor) (tree clause, tree decl, tree outer);
243 /* Build and return code for a copy constructor from SRC to DST. */
244 tree (*omp_clause_copy_ctor) (tree clause, tree dst, tree src);
246 /* Similarly, except use an assignment operator instead. */
247 tree (*omp_clause_assign_op) (tree clause, tree dst, tree src);
249 /* Build and return code for a constructor of DST that sets it to
251 tree (*omp_clause_linear_ctor) (tree clause, tree dst, tree src, tree add);
253 /* Build and return code destructing DECL. Return NULL if nothing
255 tree (*omp_clause_dtor) (tree clause, tree decl);
257 /* Do language specific checking on an implicitly determined clause. */
258 void (*omp_finish_clause) (tree clause, gimple_seq *pre_p);
261 /* Language hooks related to LTO serialization. */
263 struct lang_hooks_for_lto
265 /* Begin a new LTO section named NAME. */
266 void (*begin_section) (const char *name);
268 /* Write DATA of length LEN to the currently open LTO section. BLOCK is a
269 pointer to the dynamically allocated memory containing DATA. The
270 append_data function is responsible for freeing it when it is no longer
272 void (*append_data) (const void *data, size_t len, void *block);
274 /* End the previously begun LTO section. */
275 void (*end_section) (void);
278 /* Language-specific hooks. See langhooks-def.h for defaults. */
282 /* String identifying the front end and optionally language standard
283 version, e.g. "GNU C++98" or "GNU Java". */
286 /* sizeof (struct lang_identifier), so make_node () creates
287 identifier nodes long enough for the language-specific slots. */
288 size_t identifier_size;
290 /* Remove any parts of the tree that are used only by the FE. */
291 void (*free_lang_data) (tree);
293 /* Determines the size of any language-specific tcc_constant or
294 tcc_exceptional nodes. Since it is called from make_node, the
295 only information available is the tree code. Expected to die
296 on unrecognized codes. */
297 size_t (*tree_size) (enum tree_code);
299 /* Return the language mask used for converting argv into a sequence
301 unsigned int (*option_lang_mask) (void);
303 /* Initialize variables in an options structure. */
304 void (*init_options_struct) (struct gcc_options *opts);
306 /* After the initialize_diagnostics hook is called, do any simple
307 initialization needed before any calls to handle_option, other
308 than that done by the init_options_struct hook. */
309 void (*init_options) (unsigned int decoded_options_count,
310 struct cl_decoded_option *decoded_options);
312 /* Callback used to perform language-specific initialization for the
313 global diagnostic context structure. */
314 void (*initialize_diagnostics) (diagnostic_context *);
316 /* Return true if a warning should be given about option OPTION,
317 which is for the wrong language, false if it should be quietly
319 bool (*complain_wrong_lang_p) (const struct cl_option *option);
321 /* Handle the switch CODE, which has real type enum opt_code from
322 options.h. If the switch takes an argument, it is passed in ARG
323 which points to permanent storage. The handler is responsible for
324 checking whether ARG is NULL, which indicates that no argument
325 was in fact supplied. For -f and -W switches, VALUE is 1 or 0
326 for the positive and negative forms respectively. HANDLERS should
327 be passed to any recursive handle_option calls. LOC is the
328 location of the option.
330 Return true if the switch is valid, false if invalid. */
331 bool (*handle_option) (size_t code, const char *arg, int value, int kind,
333 const struct cl_option_handlers *handlers);
335 /* Called when all command line options have been parsed to allow
336 further processing and initialization
338 Should return true to indicate that a compiler back-end is
339 not required, such as with the -E option.
341 If errorcount is nonzero after this call the compiler exits
342 immediately and the finish hook is not called. */
343 bool (*post_options) (const char **);
345 /* Called after post_options to initialize the front end. Return
346 false to indicate that no further compilation be performed, in
347 which case the finish hook is called immediately. */
350 /* Called at the end of compilation, as a finalizer. */
351 void (*finish) (void);
353 /* Parses the entire file. */
354 void (*parse_file) (void);
356 /* Determines if it's ok for a function to have no noreturn attribute. */
357 bool (*missing_noreturn_ok_p) (tree);
359 /* Called to obtain the alias set to be used for an expression or type.
360 Returns -1 if the language does nothing special for it. */
361 alias_set_type (*get_alias_set) (tree);
363 /* Function to finish handling an incomplete decl at the end of
364 compilation. Default hook is does nothing. */
365 void (*finish_incomplete_decl) (tree);
367 /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
368 DECL_NODE with a newly GC-allocated copy. */
369 void (*dup_lang_specific_decl) (tree);
371 /* Set the DECL_ASSEMBLER_NAME for a node. If it is the sort of
372 thing that the assembler should talk about, set
373 DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
374 Otherwise, set it to the ERROR_MARK_NODE to ensure that the
375 assembler does not talk about it. */
376 void (*set_decl_assembler_name) (tree);
378 /* The front end can add its own statistics to -fmem-report with
379 this hook. It should output to stderr. */
380 void (*print_statistics) (void);
382 /* Called by print_tree when there is a tree of class tcc_exceptional
383 that it doesn't know how to display. */
384 lang_print_tree_hook print_xnode;
386 /* Called to print language-dependent parts of tcc_decl, tcc_type,
387 and IDENTIFIER_NODE nodes. */
388 lang_print_tree_hook print_decl;
389 lang_print_tree_hook print_type;
390 lang_print_tree_hook print_identifier;
392 /* Computes the name to use to print a declaration. DECL is the
393 non-NULL declaration in question. VERBOSITY determines what
394 information will be printed: 0: DECL_NAME, demangled as
395 necessary. 1: and scope information. 2: and any other
396 information that might be interesting, such as function parameter
397 types in C++. The name is in the internal character set and
398 needs to be converted to the locale character set of diagnostics,
399 or to the execution character set for strings such as
400 __PRETTY_FUNCTION__. */
401 const char *(*decl_printable_name) (tree decl, int verbosity);
403 /* Computes the dwarf-2/3 name for a tree. VERBOSITY determines what
404 information will be printed: 0: DECL_NAME, demangled as
405 necessary. 1: and scope information. */
406 const char *(*dwarf_name) (tree, int verbosity);
408 /* This compares two types for equivalence ("compatible" in C-based languages).
409 This routine should only return 1 if it is sure. It should not be used
410 in contexts where erroneously returning 0 causes problems. */
411 int (*types_compatible_p) (tree x, tree y);
413 /* Called by report_error_function to print out function name. */
414 void (*print_error_function) (diagnostic_context *, const char *,
415 struct diagnostic_info *);
417 /* Convert a character from the host's to the target's character
418 set. The character should be in what C calls the "basic source
419 character set" (roughly, the set of characters defined by plain
420 old ASCII). The default is to return the character unchanged,
421 which is correct in most circumstances. Note that both argument
422 and result should be sign-extended under -fsigned-char,
423 zero-extended under -fno-signed-char. */
424 HOST_WIDE_INT (*to_target_charset) (HOST_WIDE_INT);
426 /* Pointers to machine-independent attribute tables, for front ends
427 using attribs.c. If one is NULL, it is ignored. Respectively, a
428 table of attributes specific to the language, a table of
429 attributes common to two or more languages (to allow easy
430 sharing), and a table of attributes for checking formats. */
431 const struct attribute_spec *attribute_table;
432 const struct attribute_spec *common_attribute_table;
433 const struct attribute_spec *format_attribute_table;
435 struct lang_hooks_for_tree_inlining tree_inlining;
437 struct lang_hooks_for_tree_dump tree_dump;
439 struct lang_hooks_for_decls decls;
441 struct lang_hooks_for_types types;
443 struct lang_hooks_for_lto lto;
445 /* Returns a TREE_VEC of the generic parameters of an instantiation of
446 a generic type or decl, e.g. C++ template instantiation. If
447 TREE_CHAIN of the return value is set, it is an INTEGER_CST
448 indicating how many of the elements are non-default. */
449 tree (*get_innermost_generic_parms) (const_tree);
451 /* Returns the TREE_VEC of arguments of an instantiation
452 of a generic type of decl, e.g. C++ template instantiation. */
453 tree (*get_innermost_generic_args) (const_tree);
455 /* Determine if a tree is a function parameter pack. */
456 bool (*function_parameter_pack_p) (const_tree);
458 /* Perform language-specific gimplification on the argument. Returns an
459 enum gimplify_status, though we can't see that type here. */
460 int (*gimplify_expr) (tree *, gimple_seq *, gimple_seq *);
462 /* Do language specific processing in the builtin function DECL */
463 tree (*builtin_function) (tree decl);
465 /* Like builtin_function, but make sure the scope is the external scope.
466 This is used to delay putting in back end builtin functions until the ISA
467 that defines the builtin is declared via function specific target options,
468 which can save memory for machines like the x86_64 that have multiple
469 ISAs. If this points to the same function as builtin_function, the
470 backend must add all of the builtins at program initialization time. */
471 tree (*builtin_function_ext_scope) (tree decl);
473 /* Used to set up the tree_contains_structure array for a frontend. */
474 void (*init_ts) (void);
476 /* Called by recompute_tree_invariant_for_addr_expr to go from EXPR
477 to a contained expression or DECL, possibly updating *TC or *SE
478 if in the process TREE_CONSTANT or TREE_SIDE_EFFECTS need updating. */
479 tree (*expr_to_decl) (tree expr, bool *tc, bool *se);
481 /* The EH personality function decl. */
482 tree (*eh_personality) (void);
484 /* Map a type to a runtime object to match type. */
485 tree (*eh_runtime_type) (tree);
487 /* If non-NULL, this is a function that returns a function decl to be
488 executed if an unhandled exception is propagated out of a cleanup
489 region. For example, in C++, an exception thrown by a destructor
490 during stack unwinding is required to result in a call to
491 `std::terminate', so the C++ version of this function returns a
492 FUNCTION_DECL for `std::terminate'. */
493 tree (*eh_protect_cleanup_actions) (void);
495 /* Return true if a stmt can fallthru. Used by block_may_fallthru
496 to possibly handle language trees. */
497 bool (*block_may_fallthru) (const_tree);
499 /* True if this language uses __cxa_end_cleanup when the ARM EABI
501 bool eh_use_cxa_end_cleanup;
503 /* True if this language requires deep unsharing of tree nodes prior to
507 /* Whenever you add entries here, make sure you adjust langhooks-def.h
508 and langhooks.c accordingly. */
511 /* Each front end provides its own. */
512 extern struct lang_hooks lang_hooks;
514 extern tree add_builtin_function (const char *name, tree type,
515 int function_code, enum built_in_class cl,
516 const char *library_name,
519 extern tree add_builtin_function_ext_scope (const char *name, tree type,
521 enum built_in_class cl,
522 const char *library_name,
524 extern tree add_builtin_type (const char *name, tree type);
526 /* Language helper functions. */
528 extern bool lang_GNU_C (void);
529 extern bool lang_GNU_CXX (void);
530 extern bool lang_GNU_Fortran (void);
532 #endif /* GCC_LANG_HOOKS_H */