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   void (*post_options) PARAMS ((void));
 204
 205   /* Called after post_options, to initialize the front end.  The main
 206      input filename is passed, which may be NULL; the front end should
 207      return the original filename (e.g. foo.i -> foo.c).  Return NULL
 208      to indicate a serious error of some sort; in that case no
 209      compilation is performed, and the finish hook is called
 210      immediately.  */
 211   const char * (*init) PARAMS ((const char *));
 212
 213   /* Called at the end of compilation, as a finalizer.  */
 214   void (*finish) PARAMS ((void));
 215
 216   /* Parses the entire file.  The argument is non-zero to cause bison
 217      parsers to dump debugging information during parsing.  */
 218   void (*parse_file) PARAMS ((int));
 219
 220   /* Called immediately after parsing to clear the binding stack.  */
 221   void (*clear_binding_stack) PARAMS ((void));
 222
 223   /* Called to obtain the alias set to be used for an expression or type.
 224      Returns -1 if the language does nothing special for it.  */
 225   HOST_WIDE_INT (*get_alias_set) PARAMS ((tree));
 226
 227   /* Called with an expression that is to be processed as a constant.
 228      Returns either the same expression or a language-independent
 229      constant equivalent to its input.  */
 230   tree (*expand_constant) PARAMS ((tree));
 231
 232   /* Called by expand_expr for language-specific tree codes.
 233      Fourth argument is actually an enum expand_modifier.  */
 234   rtx (*expand_expr) PARAMS ((tree, rtx, enum machine_mode, int));
 235
 236   /* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
 237      operation.
 238
 239      This preparation consists of taking the ordinary representation
 240      of an expression expr and producing a valid tree boolean
 241      expression describing whether expr is nonzero.  We could simply
 242      always do build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
 243      but we optimize comparisons, &&, ||, and !.
 244
 245      The result should be an expression of boolean type (if not an
 246      error_mark_node).  */
 247   tree (*truthvalue_conversion) PARAMS ((tree));
 248
 249   /* Possibly apply default attributes to a function (represented by
 250      a FUNCTION_DECL).  */
 251   void (*insert_default_attributes) PARAMS ((tree));
 252
 253   /* Hook called by safe_from_p for language-specific tree codes.  It is
 254      up to the language front-end to install a hook if it has any such
 255      codes that safe_from_p needs to know about.  Since same_from_p will
 256      recursively explore the TREE_OPERANDs of an expression, this hook
 257      should not reexamine those pieces.  This routine may recursively
 258      call safe_from_p; it should always pass `0' as the TOP_P
 259      parameter.  */
 260   int (*safe_from_p) PARAMS ((rtx, tree));
 261
 262   /* Function to finish handling an incomplete decl at the end of
 263      compilation.  Default hook is does nothing.  */
 264   void (*finish_incomplete_decl) PARAMS ((tree));
 265
 266   /* Function used by unsafe_for_reeval.  A non-negative number is
 267      returned directly from unsafe_for_reeval, a negative number falls
 268      through.  The default hook returns a negative number.  */
 269   int (*unsafe_for_reeval) PARAMS ((tree));
 270
 271   /* Mark EXP saying that we need to be able to take the address of
 272      it; it should not be allocated in a register.  Return true if
 273      successful.  */
 274   bool (*mark_addressable) PARAMS ((tree));
 275
 276   /* Hook called by staticp for language-specific tree codes.  */
 277   int (*staticp) PARAMS ((tree));
 278
 279   /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
 280      DECL_NODE with a newly GC-allocated copy.  */
 281   void (*dup_lang_specific_decl) PARAMS ((tree));
 282
 283   /* Called before its argument, an UNSAVE_EXPR, is to be
 284      unsaved.  Modify it in-place so that all the evaluate only once
 285      things are cleared out.  */
 286   tree (*unsave_expr_now) PARAMS ((tree));
 287
 288   /* Called by expand_expr to build and return the cleanup-expression
 289      for the passed TARGET_EXPR.  Return NULL if there is none.  */
 290   tree (*maybe_build_cleanup) PARAMS ((tree));
 291
 292   /* Mark nodes held through the lang_specific hooks in the tree.  */
 293   void (*mark_tree) PARAMS ((tree));
 294
 295   /* Set the DECL_ASSEMBLER_NAME for a node.  If it is the sort of
 296      thing that the assembler should talk about, set
 297      DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
 298      Otherwise, set it to the ERROR_MARK_NODE to ensure that the
 299      assembler does not talk about it.  */
 300   void (*set_decl_assembler_name) PARAMS ((tree));
 301
 302   /* Nonzero if TYPE_READONLY and TREE_READONLY should always be honored.  */
 303   bool honor_readonly;
 304
 305   /* The front end can add its own statistics to -fmem-report with
 306      this hook.  It should output to stderr.  */
 307   void (*print_statistics) PARAMS ((void));
 308
 309   /* Called by print_tree when there is a tree of class 'x' that it
 310      doesn't know how to display.  */
 311   lang_print_tree_hook print_xnode;
 312
 313   /* Called to print language-dependent parts of a class 'd', class
 314      't', and IDENTIFIER_NODE nodes.  */
 315   lang_print_tree_hook print_decl;
 316   lang_print_tree_hook print_type;
 317   lang_print_tree_hook print_identifier;
 318
 319   /* Computes the name to use to print a declaration.  DECL is the
 320      non-NULL declaration in question.  VERBOSITY determines what
 321      information will be printed: 0: DECL_NAME, demangled as
 322      necessary.  1: and scope information.  2: and any other
 323      information that might be interesting, such as function parameter
 324      types in C++.  */
 325   const char *(*decl_printable_name) PARAMS ((tree decl, int verbosity));
 326
 327   /* Called by report_error_function to print out function name.  */
 328   void (*print_error_function) PARAMS ((struct diagnostic_context *,
 329                                         const char *));
 330
 331   /* Pointers to machine-independent attribute tables, for front ends
 332      using attribs.c.  If one is NULL, it is ignored.  Respectively, a
 333      table of attributes specific to the language, a table of
 334      attributes common to two or more languages (to allow easy
 335      sharing), and a table of attributes for checking formats.  */
 336   const struct attribute_spec *attribute_table;
 337   const struct attribute_spec *common_attribute_table;
 338   const struct attribute_spec *format_attribute_table;
 339
 340   /* Function-related language hooks.  */
 341   struct lang_hooks_for_functions function;
 342
 343   struct lang_hooks_for_tree_inlining tree_inlining;
 344
 345   struct lang_hooks_for_tree_dump tree_dump;
 346
 347   struct lang_hooks_for_decls decls;
 348
 349   struct lang_hooks_for_types types;
 350
 351   /* Whenever you add entries here, make sure you adjust langhooks-def.h
 352      and langhooks.c accordingly.  */
 353 };
 354
 355 /* Each front end provides its own.  */
 356 extern const struct lang_hooks lang_hooks;
 357
 358 #endif /* GCC_LANG_HOOKS_H */