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[official-gcc.git] / gcc / langhooks.h
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1 /* The lang_hooks data structure.
2 Copyright 2001, 2002, 2003, 2004 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 2, or (at your option)
9 any later version.
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 COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
21 #ifndef GCC_LANG_HOOKS_H
22 #define GCC_LANG_HOOKS_H
24 /* This file should be #include-d after tree.h. */
26 struct diagnostic_context;
28 /* A print hook for print_tree (). */
29 typedef void (*lang_print_tree_hook) (FILE *, tree, int indent);
31 /* The following hooks are documented in langhooks.c. Must not be
32 NULL. */
34 struct lang_hooks_for_tree_inlining
36 tree (*walk_subtrees) (tree *, int *,
37 tree (*) (tree *, int *, void *),
38 void *, void *);
39 int (*cannot_inline_tree_fn) (tree *);
40 int (*disregard_inline_limits) (tree);
41 tree (*add_pending_fn_decls) (void *, tree);
42 int (*auto_var_in_fn_p) (tree, tree);
43 int (*anon_aggr_type_p) (tree);
44 bool (*var_mod_type_p) (tree, tree);
45 int (*start_inlining) (tree);
46 void (*end_inlining) (tree);
47 tree (*convert_parm_for_inlining) (tree, tree, tree, int);
50 struct lang_hooks_for_callgraph
52 /* The node passed is a language-specific tree node. If its contents
53 are relevant to use of other declarations, mark them. */
54 tree (*analyze_expr) (tree *, int *, tree);
56 /* Produce RTL for function passed as argument. */
57 void (*expand_function) (tree);
60 /* Lang hooks for management of language-specific data or status
61 when entering / leaving functions etc. */
62 struct lang_hooks_for_functions
64 /* Called when entering a function. */
65 void (*init) (struct function *);
67 /* Called when leaving a function. */
68 void (*final) (struct function *);
70 /* Called when entering a nested function. */
71 void (*enter_nested) (struct function *);
73 /* Called when leaving a nested function. */
74 void (*leave_nested) (struct function *);
76 /* Determines if it's ok for a function to have no noreturn attribute. */
77 bool (*missing_noreturn_ok_p) (tree);
80 /* The following hooks are used by tree-dump.c. */
82 struct lang_hooks_for_tree_dump
84 /* Dump language-specific parts of tree nodes. Returns nonzero if it
85 does not want the usual dumping of the second argument. */
86 bool (*dump_tree) (void *, tree);
88 /* Determine type qualifiers in a language-specific way. */
89 int (*type_quals) (tree);
92 /* Hooks related to types. */
94 struct lang_hooks_for_types
96 /* Return a new type (with the indicated CODE), doing whatever
97 language-specific processing is required. */
98 tree (*make_type) (enum tree_code);
100 /* Given MODE and UNSIGNEDP, return a suitable type-tree with that
101 mode. */
102 tree (*type_for_mode) (enum machine_mode, int);
104 /* Given PRECISION and UNSIGNEDP, return a suitable type-tree for an
105 integer type with at least that precision. */
106 tree (*type_for_size) (unsigned, int);
108 /* Given an integer type T, return a type like T but unsigned.
109 If T is unsigned, the value is T. */
110 tree (*unsigned_type) (tree);
112 /* Given an integer type T, return a type like T but signed.
113 If T is signed, the value is T. */
114 tree (*signed_type) (tree);
116 /* Return a type the same as TYPE except unsigned or signed
117 according to UNSIGNEDP. */
118 tree (*signed_or_unsigned_type) (int, tree);
120 /* Given a type, apply default promotions to unnamed function
121 arguments and return the new type. Return the same type if no
122 change. Required by any language that supports variadic
123 arguments. The default hook aborts. */
124 tree (*type_promotes_to) (tree);
126 /* Register TYPE as a builtin type with the indicated NAME. The
127 TYPE is placed in the outermost lexical scope. The semantics
128 should be analogous to:
130 typedef TYPE NAME;
132 in C. The default hook ignores the declaration. */
133 void (*register_builtin_type) (tree, const char *);
135 /* This routine is called in tree.c to print an error message for
136 invalid use of an incomplete type. VALUE is the expression that
137 was used (or 0 if that isn't known) and TYPE is the type that was
138 invalid. */
139 void (*incomplete_type_error) (tree value, tree type);
141 /* Called from assign_temp to return the maximum size, if there is one,
142 for a type. */
143 tree (*max_size) (tree);
145 /* Nonzero if types that are identical are to be hashed so that only
146 one copy is kept. If a language requires unique types for each
147 user-specified type, such as Ada, this should be set to TRUE. */
148 bool hash_types;
151 /* Language hooks related to decls and the symbol table. */
153 struct lang_hooks_for_decls
155 /* Returns nonzero if we are in the global binding level. Ada
156 returns -1 for an undocumented reason used in stor-layout.c. */
157 int (*global_bindings_p) (void);
159 /* Insert BLOCK at the end of the list of subblocks of the
160 current binding level. This is used when a BIND_EXPR is expanded,
161 to handle the BLOCK node inside the BIND_EXPR. */
162 void (*insert_block) (tree);
164 /* Function to add a decl to the current scope level. Takes one
165 argument, a decl to add. Returns that decl, or, if the same
166 symbol is already declared, may return a different decl for that
167 name. */
168 tree (*pushdecl) (tree);
170 /* Returns the chain of decls so far in the current scope level. */
171 tree (*getdecls) (void);
173 /* Returns true when we should warn for an unused global DECL.
174 We will already have checked that it has static binding. */
175 bool (*warn_unused_global) (tree);
177 /* Obtain a list of globals and do final output on them at end
178 of compilation */
179 void (*final_write_globals) (void);
181 /* Do necessary preparations before assemble_variable can proceed. */
182 void (*prepare_assemble_variable) (tree);
184 /* True if this decl may be called via a sibcall. */
185 bool (*ok_for_sibcall) (tree);
188 /* Language-specific hooks. See langhooks-def.h for defaults. */
190 struct lang_hooks
192 /* String identifying the front end. e.g. "GNU C++". */
193 const char *name;
195 /* sizeof (struct lang_identifier), so make_node () creates
196 identifier nodes long enough for the language-specific slots. */
197 size_t identifier_size;
199 /* Determines the size of any language-specific 'x' or 'c' nodes.
200 Since it is called from make_node, the only information available
201 is the tree code. Expected to abort on unrecognized codes. */
202 size_t (*tree_size) (enum tree_code);
204 /* The first callback made to the front end, for simple
205 initialization needed before any calls to handle_option. Return
206 the language mask to filter the switch array with. */
207 unsigned int (*init_options) (unsigned int argc, const char **argv);
209 /* Callback used to perform language-specific initialization for the
210 global diagnostic context structure. */
211 void (*initialize_diagnostics) (struct diagnostic_context *);
213 /* Handle the switch CODE, which has real type enum opt_code from
214 options.h. If the switch takes an argument, it is passed in ARG
215 which points to permanent storage. The handler is responsible for
216 checking whether ARG is NULL, which indicates that no argument
217 was in fact supplied. For -f and -W switches, VALUE is 1 or 0
218 for the positive and negative forms respectively.
220 Return 1 if the switch is valid, 0 if invalid, and -1 if it's
221 valid and should not be treated as language-independent too. */
222 int (*handle_option) (size_t code, const char *arg, int value);
224 /* Return false to use the default complaint about a missing
225 argument, otherwise output a complaint and return true. */
226 bool (*missing_argument) (const char *opt, size_t code);
228 /* Called when all command line options have been parsed to allow
229 further processing and initialization
231 Should return true to indicate that a compiler back-end is
232 not required, such as with the -E option.
234 If errorcount is nonzero after this call the compiler exits
235 immediately and the finish hook is not called. */
236 bool (*post_options) (const char **);
238 /* Called after post_options to initialize the front end. Return
239 false to indicate that no further compilation be performed, in
240 which case the finish hook is called immediately. */
241 bool (*init) (void);
243 /* Called at the end of compilation, as a finalizer. */
244 void (*finish) (void);
246 /* Parses the entire file. The argument is nonzero to cause bison
247 parsers to dump debugging information during parsing. */
248 void (*parse_file) (int);
250 /* Called immediately after parsing to clear the binding stack. */
251 void (*clear_binding_stack) (void);
253 /* Called to obtain the alias set to be used for an expression or type.
254 Returns -1 if the language does nothing special for it. */
255 HOST_WIDE_INT (*get_alias_set) (tree);
257 /* Called with an expression that is to be processed as a constant.
258 Returns either the same expression or a language-independent
259 constant equivalent to its input. */
260 tree (*expand_constant) (tree);
262 /* Called by expand_expr for language-specific tree codes.
263 Fourth argument is actually an enum expand_modifier. */
264 rtx (*expand_expr) (tree, rtx, enum machine_mode, int, rtx *);
266 /* Called by expand_expr to generate the definition of a decl. Returns
267 1 if handled, 0 otherwise. */
268 int (*expand_decl) (tree);
270 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
271 operation.
273 This preparation consists of taking the ordinary representation
274 of an expression expr and producing a valid tree boolean
275 expression describing whether expr is nonzero. We could simply
276 always do build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
277 but we optimize comparisons, &&, ||, and !.
279 The result should be an expression of boolean type (if not an
280 error_mark_node). */
281 tree (*truthvalue_conversion) (tree);
283 /* Hook called by safe_from_p for language-specific tree codes. It is
284 up to the language front-end to install a hook if it has any such
285 codes that safe_from_p needs to know about. Since same_from_p will
286 recursively explore the TREE_OPERANDs of an expression, this hook
287 should not reexamine those pieces. This routine may recursively
288 call safe_from_p; it should always pass `0' as the TOP_P
289 parameter. */
290 int (*safe_from_p) (rtx, tree);
292 /* Function to finish handling an incomplete decl at the end of
293 compilation. Default hook is does nothing. */
294 void (*finish_incomplete_decl) (tree);
296 /* Function used by unsafe_for_reeval. A non-negative number is
297 returned directly from unsafe_for_reeval, a negative number falls
298 through. The default hook returns a negative number. */
299 int (*unsafe_for_reeval) (tree);
301 /* Mark EXP saying that we need to be able to take the address of
302 it; it should not be allocated in a register. Return true if
303 successful. */
304 bool (*mark_addressable) (tree);
306 /* Hook called by staticp for language-specific tree codes. */
307 int (*staticp) (tree);
309 /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
310 DECL_NODE with a newly GC-allocated copy. */
311 void (*dup_lang_specific_decl) (tree);
313 /* Called before its argument, an UNSAVE_EXPR, is to be
314 unsaved. Modify it in-place so that all the evaluate only once
315 things are cleared out. */
316 tree (*unsave_expr_now) (tree);
318 /* Set the DECL_ASSEMBLER_NAME for a node. If it is the sort of
319 thing that the assembler should talk about, set
320 DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
321 Otherwise, set it to the ERROR_MARK_NODE to ensure that the
322 assembler does not talk about it. */
323 void (*set_decl_assembler_name) (tree);
325 /* Return nonzero if fold-const is free to use bit-field
326 optimizations, for instance in fold_truthop(). */
327 bool (*can_use_bit_fields_p) (void);
329 /* Nonzero if operations on types narrower than their mode should
330 have their results reduced to the precision of the type. */
331 bool reduce_bit_field_operations;
333 /* Nonzero if TYPE_READONLY and TREE_READONLY should always be honored. */
334 bool honor_readonly;
336 /* Nonzero if this front end does not generate a dummy BLOCK between
337 the outermost scope of the function and the FUNCTION_DECL. See
338 is_body_block in stmt.c, and its callers. */
339 bool no_body_blocks;
341 /* The front end can add its own statistics to -fmem-report with
342 this hook. It should output to stderr. */
343 void (*print_statistics) (void);
345 /* Called by print_tree when there is a tree of class 'x' that it
346 doesn't know how to display. */
347 lang_print_tree_hook print_xnode;
349 /* Called to print language-dependent parts of a class 'd', class
350 't', and IDENTIFIER_NODE nodes. */
351 lang_print_tree_hook print_decl;
352 lang_print_tree_hook print_type;
353 lang_print_tree_hook print_identifier;
355 /* Computes the name to use to print a declaration. DECL is the
356 non-NULL declaration in question. VERBOSITY determines what
357 information will be printed: 0: DECL_NAME, demangled as
358 necessary. 1: and scope information. 2: and any other
359 information that might be interesting, such as function parameter
360 types in C++. */
361 const char *(*decl_printable_name) (tree decl, int verbosity);
363 /* This compares two types for equivalence ("compatible" in C-based languages).
364 This routine should only return 1 if it is sure. It should not be used
365 in contexts where erroneously returning 0 causes problems. */
366 int (*types_compatible_p) (tree x, tree y);
368 /* Given a CALL_EXPR, return a function decl that is its target. */
369 tree (*lang_get_callee_fndecl) (tree);
371 /* Called by report_error_function to print out function name. */
372 void (*print_error_function) (struct diagnostic_context *, const char *);
374 /* Called from expr_size to calculate the size of the value of an
375 expression in a language-dependent way. Returns a tree for the size
376 in bytes. A frontend can call lhd_expr_size to get the default
377 semantics in cases that it doesn't want to handle specially. */
378 tree (*expr_size) (tree);
380 /* Pointers to machine-independent attribute tables, for front ends
381 using attribs.c. If one is NULL, it is ignored. Respectively, a
382 table of attributes specific to the language, a table of
383 attributes common to two or more languages (to allow easy
384 sharing), and a table of attributes for checking formats. */
385 const struct attribute_spec *attribute_table;
386 const struct attribute_spec *common_attribute_table;
387 const struct attribute_spec *format_attribute_table;
389 /* Function-related language hooks. */
390 struct lang_hooks_for_functions function;
392 struct lang_hooks_for_tree_inlining tree_inlining;
394 struct lang_hooks_for_callgraph callgraph;
396 struct lang_hooks_for_tree_dump tree_dump;
398 struct lang_hooks_for_decls decls;
400 struct lang_hooks_for_types types;
402 /* Perform language-specific gimplification on the argument. Returns an
403 enum gimplify_status, though we can't see that type here. */
404 int (*gimplify_expr) (tree *, tree *, tree *);
406 /* Fold an OBJ_TYPE_REF expression to the address of a function.
407 KNOWN_TYPE carries the true type of the OBJ_TYPE_REF_OBJECT. */
408 tree (*fold_obj_type_ref) (tree, tree);
410 /* Return a definition for a builtin function named NAME and whose data type
411 is TYPE. TYPE should be a function type with argument types.
412 FUNCTION_CODE tells later passes how to compile calls to this function.
413 See tree.h for its possible values.
415 If LIBRARY_NAME is nonzero, use that for DECL_ASSEMBLER_NAME,
416 the name to be called if we can't opencode the function. If
417 ATTRS is nonzero, use that for the function's attribute list. */
418 tree (*builtin_function) (const char *name, tree type, int function_code,
419 enum built_in_class class,
420 const char *library_name, tree attrs);
422 /* Whenever you add entries here, make sure you adjust langhooks-def.h
423 and langhooks.c accordingly. */
426 /* Each front end provides its own. */
427 extern const struct lang_hooks lang_hooks;
429 #endif /* GCC_LANG_HOOKS_H */