gcc/langhooks.c

   1 /* Default language-specific hooks.
   2    Copyright 2001 Free Software Foundation, Inc.
   3    Contributed by Alexandre Oliva  <aoliva@redhat.com>
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "toplev.h"
  25 #include "tree.h"
  26 #include "c-tree.h"
  27 #include "tree-inline.h"
  28 #include "rtl.h"
  29 #include "insn-config.h"
  30 #include "integrate.h"
  31 #include "flags.h"
  32 #include "langhooks.h"
  33 #include "langhooks-def.h"
  34
  35 /* Do nothing; in many cases the default hook.  */
  36
  37 void
  38 lhd_do_nothing ()
  39 {
  40 }
  41
  42 /* Do nothing.  */
  43
  44 void
  45 lhd_do_nothing_t (t)
  46      tree t ATTRIBUTE_UNUSED;
  47 {
  48 }
  49
  50 /* Do nothing (return the tree node passed).  */
  51
  52 tree
  53 lhd_return_tree (t)
  54      tree t;
  55 {
  56   return t;
  57 }
  58
  59 /* Do nothing; the default hook to decode an option.  */
  60
  61 int
  62 lhd_decode_option (argc, argv)
  63      int argc ATTRIBUTE_UNUSED;
  64      char **argv ATTRIBUTE_UNUSED;
  65 {
  66   return 0;
  67 }
  68
  69 /* Called from by print-tree.c.  */
  70
  71 void
  72 lhd_print_tree_nothing (file, node, indent)
  73      FILE *file ATTRIBUTE_UNUSED;
  74      tree node ATTRIBUTE_UNUSED;
  75      int indent ATTRIBUTE_UNUSED;
  76 {
  77 }
  78
  79 /* Called from safe_from_p.  */
  80
  81 int
  82 lhd_safe_from_p (x, exp)
  83      rtx x ATTRIBUTE_UNUSED;
  84      tree exp ATTRIBUTE_UNUSED;
  85 {
  86   return 1;
  87 }
  88
  89 /* Called from staticp.  */
  90
  91 int
  92 lhd_staticp (exp)
  93      tree exp ATTRIBUTE_UNUSED;
  94 {
  95   return 0;
  96 }
  97
  98 /* Called when -dy is given on the command line.  */
  99
 100 void
 101 lhd_set_yydebug (value)
 102      int value;
 103 {
 104   if (value)
 105     fprintf (stderr, "warning: no yacc/bison-generated output to debug!\n");
 106 }
 107
 108 /* Provide a default routine to clear the binding stack.  This is used
 109    by languages that don't need to do anything special.  */
 110 void
 111 lhd_clear_binding_stack ()
 112 {
 113   while (! global_bindings_p ())
 114     poplevel (0, 0, 0);
 115 }
 116
 117 /* Provide a default routine for alias sets that always returns -1.  This
 118    is used by languages that don't need to do anything special.  */
 119
 120 HOST_WIDE_INT
 121 lhd_get_alias_set (t)
 122      tree t ATTRIBUTE_UNUSED;
 123 {
 124   return -1;
 125 }
 126
 127 /* Provide a hook routine for alias sets that always returns 0.  This is
 128    used by languages that haven't deal with alias sets yet.  */
 129
 130 HOST_WIDE_INT
 131 hook_get_alias_set_0 (t)
 132      tree t ATTRIBUTE_UNUSED;
 133 {
 134   return 0;
 135 }
 136
 137 /* This is the default decl_printable_name function.  */
 138
 139 const char *
 140 lhd_decl_printable_name (decl, verbosity)
 141      tree decl;
 142      int verbosity ATTRIBUTE_UNUSED;
 143 {
 144   return IDENTIFIER_POINTER (DECL_NAME (decl));
 145 }
 146
 147 /* lang_hooks.tree_inlining.walk_subtrees is called by walk_tree()
 148    after handling common cases, but before walking code-specific
 149    sub-trees.  If this hook is overridden for a language, it should
 150    handle language-specific tree codes, as well as language-specific
 151    information associated to common tree codes.  If a tree node is
 152    completely handled within this function, it should set *SUBTREES to
 153    0, so that generic handling isn't attempted.  For language-specific
 154    tree codes, generic handling would abort(), so make sure it is set
 155    properly.  Both SUBTREES and *SUBTREES is guaranteed to be non-zero
 156    when the function is called.  */
 157
 158 tree
 159 lhd_tree_inlining_walk_subtrees (tp,subtrees,func,data,htab)
 160      tree *tp ATTRIBUTE_UNUSED;
 161      int *subtrees ATTRIBUTE_UNUSED;
 162      walk_tree_fn func ATTRIBUTE_UNUSED;
 163      void *data ATTRIBUTE_UNUSED;
 164      void *htab ATTRIBUTE_UNUSED;
 165 {
 166   return NULL_TREE;
 167 }
 168
 169 /* lang_hooks.tree_inlining.cannot_inline_tree_fn is called to
 170    determine whether there are language-specific reasons for not
 171    inlining a given function.  */
 172
 173 int
 174 lhd_tree_inlining_cannot_inline_tree_fn (fnp)
 175      tree *fnp;
 176 {
 177   if (optimize == 0
 178       && lookup_attribute ("always_inline", DECL_ATTRIBUTES (*fnp)) == NULL)
 179     return 1;
 180
 181   return 0;
 182 }
 183
 184 /* lang_hooks.tree_inlining.disregard_inline_limits is called to
 185    determine whether a function should be considered for inlining even
 186    if it would exceed inlining limits.  */
 187
 188 int
 189 lhd_tree_inlining_disregard_inline_limits (fn)
 190      tree fn;
 191 {
 192   if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)) != NULL)
 193     return 1;
 194
 195   return 0;
 196 }
 197
 198 /* lang_hooks.tree_inlining.add_pending_fn_decls is called before
 199    starting to inline a function, to push any language-specific
 200    functions that should not be inlined into the current function,
 201    into VAFNP.  PFN is the top of varray, and should be returned if no
 202    functions are pushed into VAFNP.  The top of the varray should be
 203    returned.  */
 204
 205 tree
 206 lhd_tree_inlining_add_pending_fn_decls (vafnp, pfn)
 207      void *vafnp ATTRIBUTE_UNUSED;
 208      tree pfn;
 209 {
 210   return pfn;
 211 }
 212
 213 /* lang_hooks.tree_inlining.tree_chain_matters_p indicates whether the
 214    TREE_CHAIN of a language-specific tree node is relevant, i.e.,
 215    whether it should be walked, copied and preserved across copies.  */
 216
 217 int
 218 lhd_tree_inlining_tree_chain_matters_p (t)
 219      tree t ATTRIBUTE_UNUSED;
 220 {
 221   return 0;
 222 }
 223
 224 /* lang_hooks.tree_inlining.auto_var_in_fn_p is called to determine
 225    whether VT is an automatic variable defined in function FT.  */
 226
 227 int
 228 lhd_tree_inlining_auto_var_in_fn_p (var, fn)
 229      tree var, fn;
 230 {
 231   return (DECL_P (var) && DECL_CONTEXT (var) == fn
 232           && (((TREE_CODE (var) == VAR_DECL || TREE_CODE (var) == PARM_DECL)
 233                && ! TREE_STATIC (var))
 234               || TREE_CODE (var) == LABEL_DECL
 235               || TREE_CODE (var) == RESULT_DECL));
 236 }
 237
 238 /* lang_hooks.tree_inlining.copy_res_decl_for_inlining should return a
 239    declaration for the result RES of function FN to be inlined into
 240    CALLER.  NDP points to an integer that should be set in case a new
 241    declaration wasn't created (presumably because RES was of aggregate
 242    type, such that a TARGET_EXPR is used for the result).  TEXPS is a
 243    pointer to a varray with the stack of TARGET_EXPRs seen while
 244    inlining functions into caller; the top of TEXPS is supposed to
 245    match RES.  */
 246
 247 tree
 248 lhd_tree_inlining_copy_res_decl_for_inlining (res, fn, caller,
 249                                               dm, ndp, texps)
 250      tree res, fn, caller;
 251      void *dm ATTRIBUTE_UNUSED;
 252      int *ndp ATTRIBUTE_UNUSED;
 253      void *texps ATTRIBUTE_UNUSED;
 254 {
 255   return copy_decl_for_inlining (res, fn, caller);
 256 }
 257
 258 /* lang_hooks.tree_inlining.anon_aggr_type_p determines whether T is a
 259    type node representing an anonymous aggregate (union, struct, etc),
 260    i.e., one whose members are in the same scope as the union itself.  */
 261
 262 int
 263 lhd_tree_inlining_anon_aggr_type_p (t)
 264      tree t ATTRIBUTE_UNUSED;
 265 {
 266   return 0;
 267 }
 268
 269 /* lang_hooks.tree_inlining.start_inlining and end_inlining perform any
 270    language-specific bookkeeping necessary for processing
 271    FN. start_inlining returns non-zero if inlining should proceed, zero if
 272    not.
 273
 274    For instance, the C++ version keeps track of template instantiations to
 275    avoid infinite recursion.  */
 276
 277 int
 278 lhd_tree_inlining_start_inlining (fn)
 279      tree fn ATTRIBUTE_UNUSED;
 280 {
 281   return 1;
 282 }
 283
 284 void
 285 lhd_tree_inlining_end_inlining (fn)
 286      tree fn ATTRIBUTE_UNUSED;
 287 {
 288 }
 289
 290 /* lang_hooks.tree_inlining.convert_parm_for_inlining performs any
 291    language-specific conversion before assigning VALUE to PARM.  */
 292
 293 tree
 294 lhd_tree_inlining_convert_parm_for_inlining (parm, value, fndecl)
 295      tree parm ATTRIBUTE_UNUSED;
 296      tree value;
 297      tree fndecl ATTRIBUTE_UNUSED;
 298 {
 299   return value;
 300 }
 301
 302 /* lang_hooks.tree_dump.dump_tree:  Dump language-specific parts of tree
 303    nodes.  Returns non-zero if it does not want the usual dumping of the
 304    second argument.  */
 305
 306 int
 307 lhd_tree_dump_dump_tree (di, t)
 308      void *di ATTRIBUTE_UNUSED;
 309      tree t ATTRIBUTE_UNUSED;
 310 {
 311   return 0;
 312 }
 313
 314 /* lang_hooks.tree_dump.type_qual:  Determine type qualifiers in a
 315    language-specific way.  */
 316
 317 int
 318 lhd_tree_dump_type_quals (t)
 319      tree t;
 320 {
 321   return TYPE_QUALS (t);
 322 }
 323