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                                                           void *));
  52   int (*anon_aggr_type_p) PARAMS ((union tree_node *));
  53   int (*start_inlining) PARAMS ((union tree_node *));
  54   void (*end_inlining) PARAMS ((union tree_node *));
  55   union tree_node *(*convert_parm_for_inlining) PARAMS ((union tree_node *,
  56                                                          union tree_node *,
  57                                                          union tree_node *));
  58 };
  59
  60 /* Lang hooks for management of language-specific data or status
  61    when entering / leaving functions etc.  */
  62 struct lang_hooks_for_functions
  63 {
  64   /* Called when entering a function.  */
  65   void (*init) PARAMS ((struct function *));
  66
  67   /* Called when leaving a function.  */
  68   void (*free) PARAMS ((struct function *));
  69
  70   /* Called when entering a nested function.  */
  71   void (*enter_nested) PARAMS ((struct function *));
  72
  73   /* Called when leaving a nested function.  */
  74   void (*leave_nested) PARAMS ((struct function *));
  75
  76   /* Lang-specific function data marking for GC.  */
  77   void (*mark) PARAMS ((struct function *));
  78 };
  79
  80 /* The following hooks are used by tree-dump.c.  */
  81
  82 struct lang_hooks_for_tree_dump
  83 {
  84   /* Dump language-specific parts of tree nodes.  Returns non-zero if it
  85      does not want the usual dumping of the second argument.  */
  86   int (*dump_tree) PARAMS ((void *, tree));
  87
  88   /* Determine type qualifiers in a language-specific way.  */
  89   int (*type_quals) PARAMS ((tree));
  90 };
  91
  92 /* Hooks related to types.  */
  93
  94 struct lang_hooks_for_types
  95 {
  96   /* Return a new type (with the indicated CODE), doing whatever
  97      language-specific processing is required.  */
  98   tree (*make_type) PARAMS ((enum tree_code));
  99
 100   /* Given MODE and UNSIGNEDP, return a suitable type-tree with that
 101      mode.  */
 102   tree (*type_for_mode) PARAMS ((enum machine_mode, int));
 103
 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) PARAMS ((unsigned, int));
 107
 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) PARAMS ((tree));
 111
 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) PARAMS ((tree));
 115
 116   /* Return a type the same as TYPE except unsigned or signed
 117      according to UNSIGNEDP.  */
 118   tree (*signed_or_unsigned_type) PARAMS ((int, tree));
 119
 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) PARAMS ((tree));
 125
 126   /* This routine is called in tree.c to print an error message for
 127      invalid use of an incomplete type.  VALUE is the expression that
 128      was used (or 0 if that isn't known) and TYPE is the type that was
 129      invalid.  */
 130   void (*incomplete_type_error) PARAMS ((tree value, tree type));
 131 };
 132
 133 /* Language hooks related to decls and the symbol table.  */
 134
 135 struct lang_hooks_for_decls
 136 {
 137   /* Enter a new lexical scope.  Argument is always zero when called
 138      from outside the front end.  */
 139   void (*pushlevel) PARAMS ((int));
 140
 141   /* Exit a lexical scope and return a BINDING for that scope.
 142      Takes three arguments:
 143      KEEP -- nonzero if there were declarations in this scope.
 144      REVERSE -- reverse the order of decls before returning them.
 145      FUNCTIONBODY -- nonzero if this level is the body of a function.  */
 146   tree (*poplevel) PARAMS ((int, int, int));
 147
 148   /* Returns non-zero if we are in the global binding level.  Ada
 149      returns -1 for an undocumented reason used in stor-layout.c.  */
 150   int (*global_bindings_p) PARAMS ((void));
 151
 152   /* Insert BLOCK at the end of the list of subblocks of the
 153      current binding level.  This is used when a BIND_EXPR is expanded,
 154      to handle the BLOCK node inside the BIND_EXPR.  */
 155   void (*insert_block) PARAMS ((tree));
 156
 157   /* Set the BLOCK node for the current scope level.  */
 158   void (*set_block) PARAMS ((tree));
 159
 160   /* Function to add a decl to the current scope level.  Takes one
 161      argument, a decl to add.  Returns that decl, or, if the same
 162      symbol is already declared, may return a different decl for that
 163      name.  */
 164   tree (*pushdecl) PARAMS ((tree));
 165
 166   /* Returns the chain of decls so far in the current scope level.  */
 167   tree (*getdecls) PARAMS ((void));
 168
 169   /* Returns true when we should warn for an unused global DECL.
 170      We will already have checked that it has static binding.  */
 171   bool (*warn_unused_global) PARAMS ((tree));
 172 };
 173
 174 /* Language-specific hooks.  See langhooks-def.h for defaults.  */
 175
 176 struct lang_hooks
 177 {
 178   /* String identifying the front end.  e.g. "GNU C++".  */
 179   const char *name;
 180
 181   /* sizeof (struct lang_identifier), so make_node () creates
 182      identifier nodes long enough for the language-specific slots.  */
 183   size_t identifier_size;
 184
 185   /* The first callback made to the front end, for simple
 186      initialization needed before any calls to decode_option.  */
 187   void (*init_options) PARAMS ((void));
 188
 189   /* Function called with an option vector as argument, to decode a
 190      single option (typically starting with -f or -W or +).  It should
 191      return the number of command-line arguments it uses if it handles
 192      the option, or 0 and not complain if it does not recognise the
 193      option.  If this function returns a negative number, then its
 194      absolute value is the number of command-line arguments used, but,
 195      in addition, no language-independent option processing should be
 196      done for this option.  */
 197   int (*decode_option) PARAMS ((int, char **));
 198
 199   /* Called when all command line options have been parsed.  Should do
 200      any required consistency checks, modifications etc.  Complex
 201      initialization should be left to the "init" callback, since GC
 202      and the identifier hashes are set up between now and then.
 203
 204      If errorcount is non-zero after this call the compiler exits
 205      immediately and the finish hook is not called.  */
 206   void (*post_options) PARAMS ((void));
 207
 208   /* Called after post_options, to initialize the front end.  The main
 209      input filename is passed, which may be NULL; the front end should
 210      return the original filename (e.g. foo.i -> foo.c).  Return NULL
 211      to indicate a serious error of some sort; in that case no
 212      compilation is performed, and the finish hook is called
 213      immediately.  */
 214   const char * (*init) PARAMS ((const char *));
 215
 216   /* Called at the end of compilation, as a finalizer.  */
 217   void (*finish) PARAMS ((void));
 218
 219   /* Parses the entire file.  The argument is non-zero to cause bison
 220      parsers to dump debugging information during parsing.  */
 221   void (*parse_file) PARAMS ((int));
 222
 223   /* Called immediately after parsing to clear the binding stack.  */
 224   void (*clear_binding_stack) PARAMS ((void));
 225
 226   /* Called to obtain the alias set to be used for an expression or type.
 227      Returns -1 if the language does nothing special for it.  */
 228   HOST_WIDE_INT (*get_alias_set) PARAMS ((tree));
 229
 230   /* Called with an expression that is to be processed as a constant.
 231      Returns either the same expression or a language-independent
 232      constant equivalent to its input.  */
 233   tree (*expand_constant) PARAMS ((tree));
 234
 235   /* Called by expand_expr for language-specific tree codes.
 236      Fourth argument is actually an enum expand_modifier.  */
 237   rtx (*expand_expr) PARAMS ((tree, rtx, enum machine_mode, int));
 238
 239   /* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
 240      operation.
 241
 242      This preparation consists of taking the ordinary representation
 243      of an expression expr and producing a valid tree boolean
 244      expression describing whether expr is nonzero.  We could simply
 245      always do build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
 246      but we optimize comparisons, &&, ||, and !.
 247
 248      The result should be an expression of boolean type (if not an
 249      error_mark_node).  */
 250   tree (*truthvalue_conversion) PARAMS ((tree));
 251
 252   /* Possibly apply default attributes to a function (represented by
 253      a FUNCTION_DECL).  */
 254   void (*insert_default_attributes) PARAMS ((tree));
 255
 256   /* Hook called by safe_from_p for language-specific tree codes.  It is
 257      up to the language front-end to install a hook if it has any such
 258      codes that safe_from_p needs to know about.  Since same_from_p will
 259      recursively explore the TREE_OPERANDs of an expression, this hook
 260      should not reexamine those pieces.  This routine may recursively
 261      call safe_from_p; it should always pass `0' as the TOP_P
 262      parameter.  */
 263   int (*safe_from_p) PARAMS ((rtx, tree));
 264
 265   /* Function to finish handling an incomplete decl at the end of
 266      compilation.  Default hook is does nothing.  */
 267   void (*finish_incomplete_decl) PARAMS ((tree));
 268
 269   /* Function used by unsafe_for_reeval.  A non-negative number is
 270      returned directly from unsafe_for_reeval, a negative number falls
 271      through.  The default hook returns a negative number.  */
 272   int (*unsafe_for_reeval) PARAMS ((tree));
 273
 274   /* Mark EXP saying that we need to be able to take the address of
 275      it; it should not be allocated in a register.  Return true if
 276      successful.  */
 277   bool (*mark_addressable) PARAMS ((tree));
 278
 279   /* Hook called by staticp for language-specific tree codes.  */
 280   int (*staticp) PARAMS ((tree));
 281
 282   /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
 283      DECL_NODE with a newly GC-allocated copy.  */
 284   void (*dup_lang_specific_decl) PARAMS ((tree));
 285
 286   /* Called before its argument, an UNSAVE_EXPR, is to be
 287      unsaved.  Modify it in-place so that all the evaluate only once
 288      things are cleared out.  */
 289   tree (*unsave_expr_now) PARAMS ((tree));
 290
 291   /* Called by expand_expr to build and return the cleanup-expression
 292      for the passed TARGET_EXPR.  Return NULL if there is none.  */
 293   tree (*maybe_build_cleanup) PARAMS ((tree));
 294
 295   /* Mark nodes held through the lang_specific hooks in the tree.  */
 296   void (*mark_tree) PARAMS ((tree));
 297
 298   /* Set the DECL_ASSEMBLER_NAME for a node.  If it is the sort of
 299      thing that the assembler should talk about, set
 300      DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
 301      Otherwise, set it to the ERROR_MARK_NODE to ensure that the
 302      assembler does not talk about it.  */
 303   void (*set_decl_assembler_name) PARAMS ((tree));
 304
 305   /* Nonzero if TYPE_READONLY and TREE_READONLY should always be honored.  */
 306   bool honor_readonly;
 307
 308   /* The front end can add its own statistics to -fmem-report with
 309      this hook.  It should output to stderr.  */
 310   void (*print_statistics) PARAMS ((void));
 311
 312   /* Called by print_tree when there is a tree of class 'x' that it
 313      doesn't know how to display.  */
 314   lang_print_tree_hook print_xnode;
 315
 316   /* Called to print language-dependent parts of a class 'd', class
 317      't', and IDENTIFIER_NODE nodes.  */
 318   lang_print_tree_hook print_decl;
 319   lang_print_tree_hook print_type;
 320   lang_print_tree_hook print_identifier;
 321
 322   /* Computes the name to use to print a declaration.  DECL is the
 323      non-NULL declaration in question.  VERBOSITY determines what
 324      information will be printed: 0: DECL_NAME, demangled as
 325      necessary.  1: and scope information.  2: and any other
 326      information that might be interesting, such as function parameter
 327      types in C++.  */
 328   const char *(*decl_printable_name) PARAMS ((tree decl, int verbosity));
 329
 330   /* Called by report_error_function to print out function name.  */
 331   void (*print_error_function) PARAMS ((struct diagnostic_context *,
 332                                         const char *));
 333
 334   /* Pointers to machine-independent attribute tables, for front ends
 335      using attribs.c.  If one is NULL, it is ignored.  Respectively, a
 336      table of attributes specific to the language, a table of
 337      attributes common to two or more languages (to allow easy
 338      sharing), and a table of attributes for checking formats.  */
 339   const struct attribute_spec *attribute_table;
 340   const struct attribute_spec *common_attribute_table;
 341   const struct attribute_spec *format_attribute_table;
 342
 343   /* Function-related language hooks.  */
 344   struct lang_hooks_for_functions function;
 345
 346   struct lang_hooks_for_tree_inlining tree_inlining;
 347
 348   struct lang_hooks_for_tree_dump tree_dump;
 349
 350   struct lang_hooks_for_decls decls;
 351
 352   struct lang_hooks_for_types types;
 353
 354   /* Whenever you add entries here, make sure you adjust langhooks-def.h
 355      and langhooks.c accordingly.  */
 356 };
 357
 358 /* Each front end provides its own.  */
 359 extern const struct lang_hooks lang_hooks;
 360
 361 #endif /* GCC_LANG_HOOKS_H */