gcc/langhooks.h

   1 /* The lang_hooks data structure.
   2    Copyright 2001, 2002 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC 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 GNU CC 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 GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, 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 /* A print hook for print_tree ().  */
  29 typedef void (*lang_print_tree_hook) PARAMS ((FILE *, tree, int indent));
  30
  31 /* The following hooks are documented in langhooks.c.  Must not be
  32    NULL.  */
  33
  34 struct lang_hooks_for_tree_inlining
  35 {
  36   union tree_node *(*walk_subtrees) PARAMS ((union tree_node **, int *,
  37                                              union tree_node *(*)
  38                                              (union tree_node **,
  39                                               int *, void *),
  40                                              void *, void *));
  41   int (*cannot_inline_tree_fn) PARAMS ((union tree_node **));
  42   int (*disregard_inline_limits) PARAMS ((union tree_node *));
  43   union tree_node *(*add_pending_fn_decls) PARAMS ((void *,
  44                                                     union tree_node *));
  45   int (*tree_chain_matters_p) PARAMS ((union tree_node *));
  46   int (*auto_var_in_fn_p) PARAMS ((union tree_node *, union tree_node *));
  47   union tree_node *(*copy_res_decl_for_inlining) PARAMS ((union tree_node *,
  48                                                           union tree_node *,
  49                                                           union tree_node *,
  50                                                           void *, int *,
  51                                                           tree));
  52   int (*anon_aggr_type_p) PARAMS ((union tree_node *));
  53   bool (*var_mod_type_p) PARAMS ((union tree_node *));
  54   int (*start_inlining) PARAMS ((union tree_node *));
  55   void (*end_inlining) PARAMS ((union tree_node *));
  56   union tree_node *(*convert_parm_for_inlining) PARAMS ((union tree_node *,
  57                                                          union tree_node *,
  58                                                          union tree_node *));
  59 };
  60
  61 struct lang_hooks_for_callgraph
  62 {
  63   /* Function passed as argument is needed and will be compiled.
  64      Lower the representation so the calls are explicit.  */
  65   void (*lower_function) PARAMS ((union tree_node *));
  66   /* Produce RTL for function passed as argument.  */
  67   void (*expand_function) PARAMS ((union tree_node *));
  68 };
  69
  70 /* Lang hooks for management of language-specific data or status
  71    when entering / leaving functions etc.  */
  72 struct lang_hooks_for_functions
  73 {
  74   /* Called when entering a function.  */
  75   void (*init) PARAMS ((struct function *));
  76
  77   /* Called when leaving a function.  */
  78   void (*final) PARAMS ((struct function *));
  79
  80   /* Called when entering a nested function.  */
  81   void (*enter_nested) PARAMS ((struct function *));
  82
  83   /* Called when leaving a nested function.  */
  84   void (*leave_nested) PARAMS ((struct function *));
  85 };
  86
  87 /* The following hooks are used by tree-dump.c.  */
  88
  89 struct lang_hooks_for_tree_dump
  90 {
  91   /* Dump language-specific parts of tree nodes.  Returns nonzero if it
  92      does not want the usual dumping of the second argument.  */
  93   int (*dump_tree) PARAMS ((void *, tree));
  94
  95   /* Determine type qualifiers in a language-specific way.  */
  96   int (*type_quals) PARAMS ((tree));
  97 };
  98
  99 /* Hooks related to types.  */
 100
 101 struct lang_hooks_for_types
 102 {
 103   /* Return a new type (with the indicated CODE), doing whatever
 104      language-specific processing is required.  */
 105   tree (*make_type) PARAMS ((enum tree_code));
 106
 107   /* Given MODE and UNSIGNEDP, return a suitable type-tree with that
 108      mode.  */
 109   tree (*type_for_mode) PARAMS ((enum machine_mode, int));
 110
 111   /* Given PRECISION and UNSIGNEDP, return a suitable type-tree for an
 112      integer type with at least that precision.  */
 113   tree (*type_for_size) PARAMS ((unsigned, int));
 114
 115   /* Given an integer type T, return a type like T but unsigned.
 116      If T is unsigned, the value is T.  */
 117   tree (*unsigned_type) PARAMS ((tree));
 118
 119   /* Given an integer type T, return a type like T but signed.
 120      If T is signed, the value is T.  */
 121   tree (*signed_type) PARAMS ((tree));
 122
 123   /* Return a type the same as TYPE except unsigned or signed
 124      according to UNSIGNEDP.  */
 125   tree (*signed_or_unsigned_type) PARAMS ((int, tree));
 126
 127   /* Given a type, apply default promotions to unnamed function
 128      arguments and return the new type.  Return the same type if no
 129      change.  Required by any language that supports variadic
 130      arguments.  The default hook aborts.  */
 131   tree (*type_promotes_to) PARAMS ((tree));
 132
 133   /* This routine is called in tree.c to print an error message for
 134      invalid use of an incomplete type.  VALUE is the expression that
 135      was used (or 0 if that isn't known) and TYPE is the type that was
 136      invalid.  */
 137   void (*incomplete_type_error) PARAMS ((tree value, tree type));
 138 };
 139
 140 /* Language hooks related to decls and the symbol table.  */
 141
 142 struct lang_hooks_for_decls
 143 {
 144   /* Enter a new lexical scope.  Argument is always zero when called
 145      from outside the front end.  */
 146   void (*pushlevel) PARAMS ((int));
 147
 148   /* Exit a lexical scope and return a BINDING for that scope.
 149      Takes three arguments:
 150      KEEP -- nonzero if there were declarations in this scope.
 151      REVERSE -- reverse the order of decls before returning them.
 152      FUNCTIONBODY -- nonzero if this level is the body of a function.  */
 153   tree (*poplevel) PARAMS ((int, int, int));
 154
 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) PARAMS ((void));
 158
 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) PARAMS ((tree));
 163
 164   /* Set the BLOCK node for the current scope level.  */
 165   void (*set_block) PARAMS ((tree));
 166
 167   /* Function to add a decl to the current scope level.  Takes one
 168      argument, a decl to add.  Returns that decl, or, if the same
 169      symbol is already declared, may return a different decl for that
 170      name.  */
 171   tree (*pushdecl) PARAMS ((tree));
 172
 173   /* Returns the chain of decls so far in the current scope level.  */
 174   tree (*getdecls) PARAMS ((void));
 175
 176   /* Returns true when we should warn for an unused global DECL.
 177      We will already have checked that it has static binding.  */
 178   bool (*warn_unused_global) PARAMS ((tree));
 179
 180   /* Obtain a list of globals and do final output on them at end
 181      of compilation */
 182   void (*final_write_globals) PARAMS ((void));
 183 };
 184
 185 /* Language-specific hooks.  See langhooks-def.h for defaults.  */
 186
 187 struct lang_hooks
 188 {
 189   /* String identifying the front end.  e.g. "GNU C++".  */
 190   const char *name;
 191
 192   /* sizeof (struct lang_identifier), so make_node () creates
 193      identifier nodes long enough for the language-specific slots.  */
 194   size_t identifier_size;
 195
 196   /* The first callback made to the front end, for simple
 197      initialization needed before any calls to decode_option.  */
 198   void (*init_options) PARAMS ((void));
 199
 200   /* Function called with an option vector as argument, to decode a
 201      single option (typically starting with -f or -W or +).  It should
 202      return the number of command-line arguments it uses if it handles
 203      the option, or 0 and not complain if it does not recognize the
 204      option.  If this function returns a negative number, then its
 205      absolute value is the number of command-line arguments used, but,
 206      in addition, no language-independent option processing should be
 207      done for this option.  */
 208   int (*decode_option) PARAMS ((int, char **));
 209
 210   /* Called when all command line options have been parsed.  Should do
 211      any required consistency checks, modifications etc.  Complex
 212      initialization should be left to the "init" callback, since GC
 213      and the identifier hashes are set up between now and then.
 214
 215      Should return zero unless the compiler back-end does not need to
 216      be initialized, such as with the -E option.
 217
 218      If errorcount is nonzero after this call the compiler exits
 219      immediately and the finish hook is not called.  */
 220   bool (*post_options) PARAMS ((void));
 221
 222   /* Called after post_options, to initialize the front end.  The main
 223      input filename is passed, which may be NULL; the front end should
 224      return the original filename (e.g. foo.i -> foo.c).  Return NULL
 225      to indicate a serious error of some sort; in that case no
 226      compilation is performed, and the finish hook is called
 227      immediately.  */
 228   const char * (*init) PARAMS ((const char *));
 229
 230   /* Called at the end of compilation, as a finalizer.  */
 231   void (*finish) PARAMS ((void));
 232
 233   /* Parses the entire file.  The argument is nonzero to cause bison
 234      parsers to dump debugging information during parsing.  */
 235   void (*parse_file) PARAMS ((int));
 236
 237   /* Called immediately after parsing to clear the binding stack.  */
 238   void (*clear_binding_stack) PARAMS ((void));
 239
 240   /* Called to obtain the alias set to be used for an expression or type.
 241      Returns -1 if the language does nothing special for it.  */
 242   HOST_WIDE_INT (*get_alias_set) PARAMS ((tree));
 243
 244   /* Called with an expression that is to be processed as a constant.
 245      Returns either the same expression or a language-independent
 246      constant equivalent to its input.  */
 247   tree (*expand_constant) PARAMS ((tree));
 248
 249   /* Called by expand_expr for language-specific tree codes.
 250      Fourth argument is actually an enum expand_modifier.  */
 251   rtx (*expand_expr) PARAMS ((tree, rtx, enum machine_mode, int));
 252
 253   /* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
 254      operation.
 255
 256      This preparation consists of taking the ordinary representation
 257      of an expression expr and producing a valid tree boolean
 258      expression describing whether expr is nonzero.  We could simply
 259      always do build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
 260      but we optimize comparisons, &&, ||, and !.
 261
 262      The result should be an expression of boolean type (if not an
 263      error_mark_node).  */
 264   tree (*truthvalue_conversion) PARAMS ((tree));
 265
 266   /* Possibly apply default attributes to a function (represented by
 267      a FUNCTION_DECL).  */
 268   void (*insert_default_attributes) PARAMS ((tree));
 269
 270   /* Hook called by safe_from_p for language-specific tree codes.  It is
 271      up to the language front-end to install a hook if it has any such
 272      codes that safe_from_p needs to know about.  Since same_from_p will
 273      recursively explore the TREE_OPERANDs of an expression, this hook
 274      should not reexamine those pieces.  This routine may recursively
 275      call safe_from_p; it should always pass `0' as the TOP_P
 276      parameter.  */
 277   int (*safe_from_p) PARAMS ((rtx, tree));
 278
 279   /* Function to finish handling an incomplete decl at the end of
 280      compilation.  Default hook is does nothing.  */
 281   void (*finish_incomplete_decl) PARAMS ((tree));
 282
 283   /* Function used by unsafe_for_reeval.  A non-negative number is
 284      returned directly from unsafe_for_reeval, a negative number falls
 285      through.  The default hook returns a negative number.  */
 286   int (*unsafe_for_reeval) PARAMS ((tree));
 287
 288   /* Mark EXP saying that we need to be able to take the address of
 289      it; it should not be allocated in a register.  Return true if
 290      successful.  */
 291   bool (*mark_addressable) PARAMS ((tree));
 292
 293   /* Hook called by staticp for language-specific tree codes.  */
 294   int (*staticp) PARAMS ((tree));
 295
 296   /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
 297      DECL_NODE with a newly GC-allocated copy.  */
 298   void (*dup_lang_specific_decl) PARAMS ((tree));
 299
 300   /* Called before its argument, an UNSAVE_EXPR, is to be
 301      unsaved.  Modify it in-place so that all the evaluate only once
 302      things are cleared out.  */
 303   tree (*unsave_expr_now) PARAMS ((tree));
 304
 305   /* Called by expand_expr to build and return the cleanup-expression
 306      for the passed TARGET_EXPR.  Return NULL if there is none.  */
 307   tree (*maybe_build_cleanup) PARAMS ((tree));
 308
 309   /* Set the DECL_ASSEMBLER_NAME for a node.  If it is the sort of
 310      thing that the assembler should talk about, set
 311      DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
 312      Otherwise, set it to the ERROR_MARK_NODE to ensure that the
 313      assembler does not talk about it.  */
 314   void (*set_decl_assembler_name) PARAMS ((tree));
 315
 316   /* Return nonzero if fold-const is free to use bit-field
 317      optimizations, for instance in fold_truthop().  */
 318   bool (*can_use_bit_fields_p) PARAMS ((void));
 319
 320   /* Nonzero if TYPE_READONLY and TREE_READONLY should always be honored.  */
 321   bool honor_readonly;
 322
 323   /* The front end can add its own statistics to -fmem-report with
 324      this hook.  It should output to stderr.  */
 325   void (*print_statistics) PARAMS ((void));
 326
 327   /* Called by print_tree when there is a tree of class 'x' that it
 328      doesn't know how to display.  */
 329   lang_print_tree_hook print_xnode;
 330
 331   /* Called to print language-dependent parts of a class 'd', class
 332      't', and IDENTIFIER_NODE nodes.  */
 333   lang_print_tree_hook print_decl;
 334   lang_print_tree_hook print_type;
 335   lang_print_tree_hook print_identifier;
 336
 337   /* Computes the name to use to print a declaration.  DECL is the
 338      non-NULL declaration in question.  VERBOSITY determines what
 339      information will be printed: 0: DECL_NAME, demangled as
 340      necessary.  1: and scope information.  2: and any other
 341      information that might be interesting, such as function parameter
 342      types in C++.  */
 343   const char *(*decl_printable_name) PARAMS ((tree decl, int verbosity));
 344
 345   /* Called by report_error_function to print out function name.  */
 346   void (*print_error_function) PARAMS ((struct diagnostic_context *,
 347                                         const char *));
 348
 349   /* Called from expr_size to calculate the size of the value of an
 350      expression in a language-dependent way.  Returns a tree for the size
 351      in bytes.  A frontend can call lhd_expr_size to get the default
 352      semantics in cases that it doesn't want to handle specially.  */
 353   tree (*expr_size) PARAMS ((tree));
 354
 355   /* Pointers to machine-independent attribute tables, for front ends
 356      using attribs.c.  If one is NULL, it is ignored.  Respectively, a
 357      table of attributes specific to the language, a table of
 358      attributes common to two or more languages (to allow easy
 359      sharing), and a table of attributes for checking formats.  */
 360   const struct attribute_spec *attribute_table;
 361   const struct attribute_spec *common_attribute_table;
 362   const struct attribute_spec *format_attribute_table;
 363
 364   /* Function-related language hooks.  */
 365   struct lang_hooks_for_functions function;
 366
 367   struct lang_hooks_for_tree_inlining tree_inlining;
 368
 369   struct lang_hooks_for_callgraph callgraph;
 370
 371   struct lang_hooks_for_tree_dump tree_dump;
 372
 373   struct lang_hooks_for_decls decls;
 374
 375   struct lang_hooks_for_types types;
 376
 377   /* Whenever you add entries here, make sure you adjust langhooks-def.h
 378      and langhooks.c accordingly.  */
 379 };
 380
 381 /* Each front end provides its own.  */
 382 extern const struct lang_hooks lang_hooks;
 383
 384 #endif /* GCC_LANG_HOOKS_H */