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 /* A print hook for print_tree ().  */
  27 typedef void (*lang_print_tree_hook) PARAMS ((FILE *, tree, int indent));
  28
  29 /* The following hooks are documented in langhooks.c.  Must not be
  30    NULL.  */
  31
  32 struct lang_hooks_for_tree_inlining
  33 {
  34   union tree_node *(*walk_subtrees) PARAMS ((union tree_node **, int *,
  35                                              union tree_node *(*)
  36                                              (union tree_node **,
  37                                               int *, void *),
  38                                              void *, void *));
  39   int (*cannot_inline_tree_fn) PARAMS ((union tree_node **));
  40   int (*disregard_inline_limits) PARAMS ((union tree_node *));
  41   union tree_node *(*add_pending_fn_decls) PARAMS ((void *,
  42                                                     union tree_node *));
  43   int (*tree_chain_matters_p) PARAMS ((union tree_node *));
  44   int (*auto_var_in_fn_p) PARAMS ((union tree_node *, union tree_node *));
  45   union tree_node *(*copy_res_decl_for_inlining) PARAMS ((union tree_node *,
  46                                                           union tree_node *,
  47                                                           union tree_node *,
  48                                                           void *, int *,
  49                                                           void *));
  50   int (*anon_aggr_type_p) PARAMS ((union tree_node *));
  51   int (*start_inlining) PARAMS ((union tree_node *));
  52   void (*end_inlining) PARAMS ((union tree_node *));
  53   union tree_node *(*convert_parm_for_inlining) PARAMS ((union tree_node *,
  54                                                          union tree_node *,
  55                                                          union tree_node *));
  56 };
  57
  58 /* The following hooks are used by tree-dump.c.  */
  59
  60 struct lang_hooks_for_tree_dump
  61 {
  62   /* Dump language-specific parts of tree nodes.  Returns non-zero if it
  63      does not want the usual dumping of the second argument.  */
  64   int (*dump_tree) PARAMS ((void *, tree));
  65
  66   /* Determine type qualifiers in a language-specific way.  */
  67   int (*type_quals) PARAMS ((tree));
  68 };
  69
  70 /* Hooks related to types.  */
  71
  72 struct lang_hooks_for_types
  73 {
  74   tree (*make_type) PARAMS ((enum tree_code));
  75 };
  76
  77 /* Language hooks related to decls and the symbol table.  */
  78
  79 struct lang_hooks_for_decls
  80 {
  81   /* Enter a new lexical scope.  Argument is always zero when called
  82      from outside the front end.  */
  83   void (*pushlevel) PARAMS ((int));
  84
  85   /* Exit a lexical scope and return a BINDING for that scope.
  86      Takes three arguments:
  87      KEEP -- nonzero if there were declarations in this scope.
  88      REVERSE -- reverse the order of decls before returning them.
  89      FUNCTIONBODY -- nonzero if this level is the body of a function.  */
  90   tree (*poplevel) PARAMS ((int, int, int));
  91
  92   /* Returns non-zero if we are in the global binding level.  Ada
  93      returns -1 for an undocumented reason used in stor-layout.c.  */
  94   int (*global_bindings_p) PARAMS ((void));
  95
  96   /* Insert BLOCK at the end of the list of subblocks of the
  97      current binding level.  This is used when a BIND_EXPR is expanded,
  98      to handle the BLOCK node inside the BIND_EXPR.  */
  99   void (*insert_block) PARAMS ((tree));
 100
 101   /* Set the BLOCK node for the current scope level.  */
 102   void (*set_block) PARAMS ((tree));
 103
 104   /* Function to add a decl to the current scope level.  Takes one
 105      argument, a decl to add.  Returns that decl, or, if the same
 106      symbol is already declared, may return a different decl for that
 107      name.  */
 108   tree (*pushdecl) PARAMS ((tree));
 109
 110   /* Returns the chain of decls so far in the current scope level.  */
 111   tree (*getdecls) PARAMS ((void));
 112 };
 113
 114 /* Language-specific hooks.  See langhooks-def.h for defaults.  */
 115
 116 struct lang_hooks
 117 {
 118   /* String identifying the front end.  e.g. "GNU C++".  */
 119   const char *name;
 120
 121   /* sizeof (struct lang_identifier), so make_node () creates
 122      identifier nodes long enough for the language-specific slots.  */
 123   size_t identifier_size;
 124
 125   /* The first callback made to the front end, for simple
 126      initialization needed before any calls to decode_option.  */
 127   void (*init_options) PARAMS ((void));
 128
 129   /* Function called with an option vector as argument, to decode a
 130      single option (typically starting with -f or -W or +).  It should
 131      return the number of command-line arguments it uses if it handles
 132      the option, or 0 and not complain if it does not recognise the
 133      option.  If this function returns a negative number, then its
 134      absolute value is the number of command-line arguments used, but,
 135      in addition, no language-independent option processing should be
 136      done for this option.  */
 137   int (*decode_option) PARAMS ((int, char **));
 138
 139   /* Called when all command line options have been parsed.  Should do
 140      any required consistency checks, modifications etc.  Complex
 141      initialization should be left to the "init" callback, since GC
 142      and the identifier hashes are set up between now and then.  */
 143   void (*post_options) PARAMS ((void));
 144
 145   /* Called after post_options, to initialize the front end.  The main
 146      input filename is passed, which may be NULL; the front end should
 147      return the original filename (e.g. foo.i -> foo.c).  Return NULL
 148      to indicate a serious error of some sort; in that case no
 149      compilation is performed, and the finish hook is called
 150      immediately.  */
 151   const char * (*init) PARAMS ((const char *));
 152
 153   /* Called at the end of compilation, as a finalizer.  */
 154   void (*finish) PARAMS ((void));
 155
 156   /* Parses the entire file.  */
 157   void (*parse_file) PARAMS ((void));
 158
 159   /* Called immediately after parsing to clear the binding stack.  */
 160   void (*clear_binding_stack) PARAMS ((void));
 161
 162   /* Called to obtain the alias set to be used for an expression or type.
 163      Returns -1 if the language does nothing special for it.  */
 164   HOST_WIDE_INT (*get_alias_set) PARAMS ((tree));
 165
 166   /* Called with an expression that is to be processed as a constant.
 167      Returns either the same expression or a language-independent
 168      constant equivalent to its input.  */
 169   tree (*expand_constant) PARAMS ((tree));
 170
 171   /* Called by expand_expr for language-specific tree codes.
 172      Fourth argument is actually an enum expand_modifier.  */
 173   rtx (*expand_expr) PARAMS ((tree, rtx, enum machine_mode, int));
 174
 175   /* Possibly apply default attributes to a function (represented by
 176      a FUNCTION_DECL).  */
 177   void (*insert_default_attributes) PARAMS ((tree));
 178
 179   /* Hook called by safe_from_p for language-specific tree codes.  It is
 180      up to the language front-end to install a hook if it has any such
 181      codes that safe_from_p needs to know about.  Since same_from_p will
 182      recursively explore the TREE_OPERANDs of an expression, this hook
 183      should not reexamine those pieces.  This routine may recursively
 184      call safe_from_p; it should always pass `0' as the TOP_P
 185      parameter.  */
 186   int (*safe_from_p) PARAMS ((rtx, tree));
 187
 188   /* Hook called by staticp for language-specific tree codes.  */
 189   int (*staticp) PARAMS ((tree));
 190
 191   /* Replace the DECL_LANG_SPECIFIC data, which may be NULL, of the
 192      DECL_NODE with a newly GC-allocated copy.  */
 193   void (*dup_lang_specific_decl) PARAMS ((tree));
 194
 195   /* Called before its argument, an UNSAVE_EXPR, is to be
 196      unsaved.  Modify it in-place so that all the evaluate only once
 197      things are cleared out.  */
 198   tree (*unsave_expr_now) PARAMS ((tree));
 199
 200   /* Called by expand_expr to build and return the cleanup-expression
 201      for the passed TARGET_EXPR.  Return NULL if there is none.  */
 202   tree (*maybe_build_cleanup) PARAMS ((tree));
 203
 204   /* Mark nodes held through the lang_specific hooks in the tree.  */
 205   void (*mark_tree) PARAMS ((tree));
 206
 207   /* Nonzero if TYPE_READONLY and TREE_READONLY should always be honored.  */
 208   bool honor_readonly;
 209
 210   /* The front end can add its own statistics to -fmem-report with
 211      this hook.  It should output to stderr.  */
 212   void (*print_statistics) PARAMS ((void));
 213
 214   /* Called by print_tree when there is a tree of class 'x' that it
 215      doesn't know how to display.  */
 216   lang_print_tree_hook print_xnode;
 217
 218   /* Called to print language-dependent parts of a class 'd', class
 219      't', and IDENTIFIER_NODE nodes.  */
 220   lang_print_tree_hook print_decl;
 221   lang_print_tree_hook print_type;
 222   lang_print_tree_hook print_identifier;
 223
 224   /* Computes the name to use to print a declaration.  DECL is the
 225      non-NULL declaration in question.  VERBOSITY determines what
 226      information will be printed: 0: DECL_NAME, demangled as
 227      necessary.  1: and scope information.  2: and any other
 228      information that might be interesting, such as function parameter
 229      types in C++.  */
 230   const char *(*decl_printable_name) PARAMS ((tree decl, int verbosity));
 231
 232   /* Set yydebug for bison-based parsers, when -dy is given on the
 233      command line.  By default, if the parameter is non-zero, prints a
 234      warning that the front end does not use such a parser.  */
 235   void (*set_yydebug) PARAMS ((int));
 236
 237   struct lang_hooks_for_tree_inlining tree_inlining;
 238
 239   struct lang_hooks_for_tree_dump tree_dump;
 240
 241   struct lang_hooks_for_decls decls;
 242
 243   struct lang_hooks_for_types types;
 244
 245   /* Whenever you add entries here, make sure you adjust langhooks-def.h
 246      and langhooks.c accordingly.  */
 247 };
 248
 249 /* Each front end provides its own.  */
 250 extern const struct lang_hooks lang_hooks;
 251
 252 #endif /* GCC_LANG_HOOKS_H */