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 "langhooks.h"
  32 #include "langhooks-def.h"
  33
  34 /* Do nothing; in many cases the default hook.  */
  35
  36 void
  37 lhd_do_nothing ()
  38 {
  39 }
  40
  41 /* Do nothing; the default hook to decode an option.  */
  42
  43 int
  44 lhd_decode_option (argc, argv)
  45      int argc ATTRIBUTE_UNUSED;
  46      char **argv ATTRIBUTE_UNUSED;
  47 {
  48   return 0;
  49 }
  50
  51 /* Called from by print-tree.c.  */
  52
  53 void
  54 lhd_print_tree_nothing (file, node, indent)
  55      FILE *file ATTRIBUTE_UNUSED;
  56      tree node ATTRIBUTE_UNUSED;
  57      int indent ATTRIBUTE_UNUSED;
  58 {
  59 }
  60
  61 /* Called when -dy is given on the command line.  */
  62
  63 void
  64 lhd_set_yydebug (value)
  65      int value;
  66 {
  67   if (value)
  68     fprintf (stderr, "warning: no yacc/bison-generated output to debug!\n");
  69 }
  70
  71 /* Provide a default routine to clear the binding stack.  This is used
  72    by languages that don't need to do anything special.  */
  73 void
  74 lhd_clear_binding_stack ()
  75 {
  76   while (! global_bindings_p ())
  77     poplevel (0, 0, 0);
  78 }
  79
  80 /* Provide a default routine for alias sets that always returns -1.  This
  81    is used by languages that don't need to do anything special.  */
  82
  83 HOST_WIDE_INT
  84 lhd_get_alias_set (t)
  85      tree t ATTRIBUTE_UNUSED;
  86 {
  87   return -1;
  88 }
  89
  90 /* Provide a hook routine for alias sets that always returns 0.  This is
  91    used by languages that haven't deal with alias sets yet.  */
  92
  93 HOST_WIDE_INT
  94 hook_get_alias_set_0 (t)
  95      tree t ATTRIBUTE_UNUSED;
  96 {
  97   return 0;
  98 }
  99
 100 /* lang_hooks.tree_inlining.walk_subtrees is called by walk_tree()
 101    after handling common cases, but before walking code-specific
 102    sub-trees.  If this hook is overridden for a language, it should
 103    handle language-specific tree codes, as well as language-specific
 104    information associated to common tree codes.  If a tree node is
 105    completely handled within this function, it should set *SUBTREES to
 106    0, so that generic handling isn't attempted.  For language-specific
 107    tree codes, generic handling would abort(), so make sure it is set
 108    properly.  Both SUBTREES and *SUBTREES is guaranteed to be non-zero
 109    when the function is called.  */
 110
 111 tree
 112 lhd_tree_inlining_walk_subtrees (tp,subtrees,func,data,htab)
 113      tree *tp ATTRIBUTE_UNUSED;
 114      int *subtrees ATTRIBUTE_UNUSED;
 115      walk_tree_fn func ATTRIBUTE_UNUSED;
 116      void *data ATTRIBUTE_UNUSED;
 117      void *htab ATTRIBUTE_UNUSED;
 118 {
 119   return NULL_TREE;
 120 }
 121
 122 /* lang_hooks.tree_inlining.cannot_inline_tree_fn is called to
 123    determine whether there are language-specific reasons for not
 124    inlining a given function.  */
 125
 126 int
 127 lhd_tree_inlining_cannot_inline_tree_fn (fnp)
 128      tree *fnp ATTRIBUTE_UNUSED;
 129 {
 130   return 0;
 131 }
 132
 133 /* lang_hooks.tree_inlining.disregard_inline_limits is called to
 134    determine whether a function should be considered for inlining even
 135    if it would exceed inlining limits.  */
 136
 137 int
 138 lhd_tree_inlining_disregard_inline_limits (fn)
 139      tree fn ATTRIBUTE_UNUSED;
 140 {
 141   return 0;
 142 }
 143
 144 /* lang_hooks.tree_inlining.add_pending_fn_decls is called before
 145    starting to inline a function, to push any language-specific
 146    functions that should not be inlined into the current function,
 147    into VAFNP.  PFN is the top of varray, and should be returned if no
 148    functions are pushed into VAFNP.  The top of the varray should be
 149    returned.  */
 150
 151 tree
 152 lhd_tree_inlining_add_pending_fn_decls (vafnp, pfn)
 153      void *vafnp ATTRIBUTE_UNUSED;
 154      tree pfn;
 155 {
 156   return pfn;
 157 }
 158
 159 /* lang_hooks.tree_inlining.tree_chain_matters_p indicates whether the
 160    TREE_CHAIN of a language-specific tree node is relevant, i.e.,
 161    whether it should be walked, copied and preserved across copies.  */
 162
 163 int
 164 lhd_tree_inlining_tree_chain_matters_p (t)
 165      tree t ATTRIBUTE_UNUSED;
 166 {
 167   return 0;
 168 }
 169
 170 /* lang_hooks.tree_inlining.auto_var_in_fn_p is called to determine
 171    whether VT is an automatic variable defined in function FT.  */
 172
 173 int
 174 lhd_tree_inlining_auto_var_in_fn_p (var, fn)
 175      tree var, fn;
 176 {
 177   return (DECL_P (var) && DECL_CONTEXT (var) == fn
 178           && (((TREE_CODE (var) == VAR_DECL || TREE_CODE (var) == PARM_DECL)
 179                && ! TREE_STATIC (var))
 180               || TREE_CODE (var) == LABEL_DECL
 181               || TREE_CODE (var) == RESULT_DECL));
 182 }
 183
 184 /* lang_hooks.tree_inlining.copy_res_decl_for_inlining should return a
 185    declaration for the result RES of function FN to be inlined into
 186    CALLER.  NDP points to an integer that should be set in case a new
 187    declaration wasn't created (presumably because RES was of aggregate
 188    type, such that a TARGET_EXPR is used for the result).  TEXPS is a
 189    pointer to a varray with the stack of TARGET_EXPRs seen while
 190    inlining functions into caller; the top of TEXPS is supposed to
 191    match RES.  */
 192
 193 tree
 194 lhd_tree_inlining_copy_res_decl_for_inlining (res, fn, caller,
 195                                               dm, ndp, texps)
 196      tree res, fn, caller;
 197      void *dm ATTRIBUTE_UNUSED;
 198      int *ndp ATTRIBUTE_UNUSED;
 199      void *texps ATTRIBUTE_UNUSED;
 200 {
 201   return copy_decl_for_inlining (res, fn, caller);
 202 }
 203
 204 /* lang_hooks.tree_inlining.anon_aggr_type_p determines whether T is a
 205    type node representing an anonymous aggregate (union, struct, etc),
 206    i.e., one whose members are in the same scope as the union itself.  */
 207
 208 int
 209 lhd_tree_inlining_anon_aggr_type_p (t)
 210      tree t ATTRIBUTE_UNUSED;
 211 {
 212   return 0;
 213 }
 214
 215 /* lang_hooks.tree_dump.dump_tree:  Dump language-specific parts of tree
 216    nodes.  Returns non-zero if it does not want the usual dumping of the
 217    second argument.  */
 218
 219 int
 220 lhd_tree_dump_dump_tree (di, t)
 221      void *di ATTRIBUTE_UNUSED;
 222      tree t ATTRIBUTE_UNUSED;
 223 {
 224   return 0;
 225 }
 226
 227 /* lang_hooks.tree_dump.type_qual:  Determine type qualifiers in a
 228    language-specific way.  */
 229
 230 int
 231 lhd_tree_dump_type_quals (t)
 232      tree t;
 233 {
 234   return TYPE_QUALS (t);
 235 }
 236