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 /* The following hooks are used by tree-dump.c.  */
  61
  62 struct lang_hooks_for_tree_dump
  63 {
  64   /* Dump language-specific parts of tree nodes.  Returns non-zero if it
  65      does not want the usual dumping of the second argument.  */
  66   int (*dump_tree) PARAMS ((void *, tree));
  67
  68   /* Determine type qualifiers in a language-specific way.  */
  69   int (*type_quals) PARAMS ((tree));
  70 };
  71
  72 /* Hooks related to types.  */
  73
  74 struct lang_hooks_for_types
  75 {
  76   /* Return a new type (with the indicated CODE), doing whatever
  77      language-specific processing is required.  */
  78   tree (*make_type) PARAMS ((enum tree_code));
  79
  80   /* Given MODE and UNSIGNEDP, return a suitable type-tree with that
  81      mode.  */
  82   tree (*type_for_mode) PARAMS ((enum machine_mode, int));
  83
  84   /* Given PRECISION and UNSIGNEDP, return a suitable type-tree for an
  85      integer type with at least that precision.  */
  86   tree (*type_for_size) PARAMS ((unsigned, int));
  87
  88   /* Given an integer type T, return a type like T but unsigned.
  89      If T is unsigned, the value is T.  */
  90   tree (*unsigned_type) PARAMS ((tree));
  91
  92   /* Given an integer type T, return a type like T but signed.
  93      If T is signed, the value is T.  */
  94   tree (*signed_type) PARAMS ((tree));
  95
  96   /* Return a type the same as TYPE except unsigned or signed
  97      according to UNSIGNEDP.  */
  98   tree (*signed_or_unsigned_type) PARAMS ((int, tree));
  99 };
 100
 101 /* Language hooks related to decls and the symbol table.  */
 102
 103 struct lang_hooks_for_decls
 104 {
 105   /* Enter a new lexical scope.  Argument is always zero when called
 106      from outside the front end.  */
 107   void (*pushlevel) PARAMS ((int));
 108
 109   /* Exit a lexical scope and return a BINDING for that scope.
 110      Takes three arguments:
 111      KEEP -- nonzero if there were declarations in this scope.
 112      REVERSE -- reverse the order of decls before returning them.
 113      FUNCTIONBODY -- nonzero if this level is the body of a function.  */
 114   tree (*poplevel) PARAMS ((int, int, int));
 115
 116   /* Returns non-zero if we are in the global binding level.  Ada
 117      returns -1 for an undocumented reason used in stor-layout.c.  */
 118   int (*global_bindings_p) PARAMS ((void));
 119
 120   /* Insert BLOCK at the end of the list of subblocks of the
 121      current binding level.  This is used when a BIND_EXPR is expanded,
 122      to handle the BLOCK node inside the BIND_EXPR.  */
 123   void (*insert_block) PARAMS ((tree));
 124
 125   /* Set the BLOCK node for the current scope level.  */
 126   void (*set_block) PARAMS ((tree));
 127
 128   /* Function to add a decl to the current scope level.  Takes one
 129      argument, a decl to add.  Returns that decl, or, if the same
 130      symbol is already declared, may return a different decl for that
 131      name.  */
 132   tree (*pushdecl) PARAMS ((tree));
 133
 134   /* Returns the chain of decls so far in the current scope level.  */
 135   tree (*getdecls) PARAMS ((void));
 136
 137   /* Returns true when we should warn for an unused global DECL.
 138      We will already have checked that it has static binding.  */
 139   bool (*warn_unused_global) PARAMS ((tree));
 140 };
 141
 142 /* Language-specific hooks.  See langhooks-def.h for defaults.  */
 143
 144 struct lang_hooks
 145 {
 146   /* String identifying the front end.  e.g. "GNU C++".  */
 147   const char *name;
 148
 149   /* sizeof (struct lang_identifier), so make_node () creates
 150      identifier nodes long enough for the language-specific slots.  */
 151   size_t identifier_size;
 152
 153   /* The first callback made to the front end, for simple
 154      initialization needed before any calls to decode_option.  */
 155   void (*init_options) PARAMS ((void));
 156
 157   /* Function called with an option vector as argument, to decode a
 158      single option (typically starting with -f or -W or +).  It should
 159      return the number of command-line arguments it uses if it handles
 160      the option, or 0 and not complain if it does not recognise the
 161      option.  If this function returns a negative number, then its
 162      absolute value is the number of command-line arguments used, but,
 163      in addition, no language-independent option processing should be
 164      done for this option.  */
 165   int (*decode_option) PARAMS ((int, char **));
 166
 167   /* Called when all command line options have been parsed.  Should do
 168      any required consistency checks, modifications etc.  Complex
 169      initialization should be left to the "init" callback, since GC
 170      and the identifier hashes are set up between now and then.  */
 171   void (*post_options) PARAMS ((void));
 172
 173   /* Called after post_options, to initialize the front end.  The main
 174      input filename is passed, which may be NULL; the front end should
 175      return the original filename (e.g. foo.i -> foo.c).  Return NULL
 176      to indicate a serious error of some sort; in that case no
 177      compilation is performed, and the finish hook is called
 178      immediately.  */
 179   const char * (*init) PARAMS ((const char *));
 180
 181   /* Called at the end of compilation, as a finalizer.  */
 182   void (*finish) PARAMS ((void));
 183
 184   /* Parses the entire file.  */
 185   void (*parse_file) PARAMS ((void));
 186
 187   /* Called immediately after parsing to clear the binding stack.  */
 188   void (*clear_binding_stack) PARAMS ((void));
 189
 190   /* Called to obtain the alias set to be used for an expression or type.
 191      Returns -1 if the language does nothing special for it.  */
 192   HOST_WIDE_INT (*get_alias_set) PARAMS ((tree));
 193
 194   /* Called with an expression that is to be processed as a constant.
 195      Returns either the same expression or a language-independent
 196      constant equivalent to its input.  */
 197   tree (*expand_constant) PARAMS ((tree));
 198
 199   /* Called by expand_expr for language-specific tree codes.
 200      Fourth argument is actually an enum expand_modifier.  */
 201   rtx (*expand_expr) PARAMS ((tree, rtx, enum machine_mode, int));
 202
 203   /* Prepare expr to be an argument of a TRUTH_NOT_EXPR or other logical
 204      operation.
 205
 206      This preparation consists of taking the ordinary representation
 207      of an expression expr and producing a valid tree boolean
 208      expression describing whether expr is nonzero.  We could simply
 209      always do build_binary_op (NE_EXPR, expr, integer_zero_node, 1),
 210      but we optimize comparisons, &&, ||, and !.
 211
 212      The result should be an expression of boolean type (if not an
 213      error_mark_node).  */
 214   tree (*truthvalue_conversion) PARAMS ((tree));
 215
 216   /* Possibly apply default attributes to a function (represented by
 217      a FUNCTION_DECL).  */
 218   void (*insert_default_attributes) PARAMS ((tree));
 219
 220   /* Hook called by safe_from_p for language-specific tree codes.  It is
 221      up to the language front-end to install a hook if it has any such
 222      codes that safe_from_p needs to know about.  Since same_from_p will
 223      recursively explore the TREE_OPERANDs of an expression, this hook
 224      should not reexamine those pieces.  This routine may recursively
 225      call safe_from_p; it should always pass `0' as the TOP_P
 226      parameter.  */
 227   int (*safe_from_p) PARAMS ((rtx, tree));
 228
 229   /* Function to finish handling an incomplete decl at the end of
 230      compilation.  Default hook is does nothing.  */
 231   void (*finish_incomplete_decl) PARAMS ((tree));
 232
 233   /* Function used by unsafe_for_reeval.  A non-negative number is
 234      returned directly from unsafe_for_reeval, a negative number falls
 235      through.  The default hook returns a negative number.  */
 236   int (*unsafe_for_reeval) PARAMS ((tree));
 237
 238   /* Mark EXP saying that we need to be able to take the address of
 239      it; it should not be allocated in a register.  Return true if
 240      successful.  */
 241   bool (*mark_addressable) PARAMS ((tree));
 242
 243   /* Hook called by staticp for language-specific tree codes.  */
 244   int (*staticp) PARAMS ((tree));
 245
 246   /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
 247      DECL_NODE with a newly GC-allocated copy.  */
 248   void (*dup_lang_specific_decl) PARAMS ((tree));
 249
 250   /* Called before its argument, an UNSAVE_EXPR, is to be
 251      unsaved.  Modify it in-place so that all the evaluate only once
 252      things are cleared out.  */
 253   tree (*unsave_expr_now) PARAMS ((tree));
 254
 255   /* Called by expand_expr to build and return the cleanup-expression
 256      for the passed TARGET_EXPR.  Return NULL if there is none.  */
 257   tree (*maybe_build_cleanup) PARAMS ((tree));
 258
 259   /* Mark nodes held through the lang_specific hooks in the tree.  */
 260   void (*mark_tree) PARAMS ((tree));
 261
 262   /* Set the DECL_ASSEMBLER_NAME for a node.  If it is the sort of
 263      thing that the assembler should talk about, set
 264      DECL_ASSEMBLER_NAME to an appropriate IDENTIFIER_NODE.
 265      Otherwise, set it to the ERROR_MARK_NODE to ensure that the
 266      assembler does not talk about it.  */
 267   void (*set_decl_assembler_name) PARAMS ((tree));
 268
 269   /* Nonzero if TYPE_READONLY and TREE_READONLY should always be honored.  */
 270   bool honor_readonly;
 271
 272   /* The front end can add its own statistics to -fmem-report with
 273      this hook.  It should output to stderr.  */
 274   void (*print_statistics) PARAMS ((void));
 275
 276   /* Called by print_tree when there is a tree of class 'x' that it
 277      doesn't know how to display.  */
 278   lang_print_tree_hook print_xnode;
 279
 280   /* Called to print language-dependent parts of a class 'd', class
 281      't', and IDENTIFIER_NODE nodes.  */
 282   lang_print_tree_hook print_decl;
 283   lang_print_tree_hook print_type;
 284   lang_print_tree_hook print_identifier;
 285
 286   /* Computes the name to use to print a declaration.  DECL is the
 287      non-NULL declaration in question.  VERBOSITY determines what
 288      information will be printed: 0: DECL_NAME, demangled as
 289      necessary.  1: and scope information.  2: and any other
 290      information that might be interesting, such as function parameter
 291      types in C++.  */
 292   const char *(*decl_printable_name) PARAMS ((tree decl, int verbosity));
 293
 294   /* Called by report_error_function to print out function name.  */
 295   void (*print_error_function) PARAMS ((struct diagnostic_context *,
 296                                         const char *));
 297
 298   /* Set yydebug for bison-based parsers, when -dy is given on the
 299      command line.  By default, if the parameter is non-zero, prints a
 300      warning that the front end does not use such a parser.  */
 301   void (*set_yydebug) PARAMS ((int));
 302
 303   struct lang_hooks_for_tree_inlining tree_inlining;
 304
 305   struct lang_hooks_for_tree_dump tree_dump;
 306
 307   struct lang_hooks_for_decls decls;
 308
 309   struct lang_hooks_for_types types;
 310
 311   /* Whenever you add entries here, make sure you adjust langhooks-def.h
 312      and langhooks.c accordingly.  */
 313 };
 314
 315 /* Each front end provides its own.  */
 316 extern const struct lang_hooks lang_hooks;
 317
 318 #endif /* GCC_LANG_HOOKS_H */