gcc/integrate.c

   1 /* Procedure integration for GCC.
   2    Copyright (C) 1988, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   3    2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   4    Contributed by Michael Tiemann (tiemann@cygnus.com)
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING.  If not, write to the Free
  20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  21 02111-1307, USA.  */
  22
  23 #include "config.h"
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "tm.h"
  27
  28 #include "rtl.h"
  29 #include "tree.h"
  30 #include "tm_p.h"
  31 #include "regs.h"
  32 #include "flags.h"
  33 #include "debug.h"
  34 #include "insn-config.h"
  35 #include "expr.h"
  36 #include "output.h"
  37 #include "recog.h"
  38 #include "integrate.h"
  39 #include "real.h"
  40 #include "except.h"
  41 #include "function.h"
  42 #include "toplev.h"
  43 #include "intl.h"
  44 #include "params.h"
  45 #include "ggc.h"
  46 #include "target.h"
  47 #include "langhooks.h"
  48
  49 /* Round to the next highest integer that meets the alignment.  */
  50 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
  51 \f
  52
  53 /* Private type used by {get/has}_hard_reg_initial_val.  */
  54 typedef struct initial_value_pair GTY(()) {
  55   rtx hard_reg;
  56   rtx pseudo;
  57 } initial_value_pair;
  58 typedef struct initial_value_struct GTY(()) {
  59   int num_entries;
  60   int max_entries;
  61   initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
  62 } initial_value_struct;
  63
  64 static void set_block_origin_self (tree);
  65 static void set_block_abstract_flags (tree, int);
  66 \f
  67
  68 /* Return false if the function FNDECL cannot be inlined on account of its
  69    attributes, true otherwise.  */
  70 bool
  71 function_attribute_inlinable_p (tree fndecl)
  72 {
  73   if (targetm.attribute_table)
  74     {
  75       tree a;
  76
  77       for (a = DECL_ATTRIBUTES (fndecl); a; a = TREE_CHAIN (a))
  78         {
  79           tree name = TREE_PURPOSE (a);
  80           int i;
  81
  82           for (i = 0; targetm.attribute_table[i].name != NULL; i++)
  83             if (is_attribute_p (targetm.attribute_table[i].name, name))
  84               return targetm.function_attribute_inlinable_p (fndecl);
  85         }
  86     }
  87
  88   return true;
  89 }
  90 \f
  91 /* Copy NODE (which must be a DECL).  The DECL originally was in the FROM_FN,
  92    but now it will be in the TO_FN.  */
  93
  94 tree
  95 copy_decl_for_inlining (tree decl, tree from_fn, tree to_fn)
  96 {
  97   tree copy;
  98
  99   /* Copy the declaration.  */
 100   if (TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == RESULT_DECL)
 101     {
 102       tree type = TREE_TYPE (decl);
 103
 104       /* For a parameter or result, we must make an equivalent VAR_DECL, not a
 105          new PARM_DECL.  */
 106       copy = build_decl (VAR_DECL, DECL_NAME (decl), type);
 107       TREE_ADDRESSABLE (copy) = TREE_ADDRESSABLE (decl);
 108       TREE_READONLY (copy) = TREE_READONLY (decl);
 109       TREE_THIS_VOLATILE (copy) = TREE_THIS_VOLATILE (decl);
 110     }
 111   else
 112     {
 113       copy = copy_node (decl);
 114       /* The COPY is not abstract; it will be generated in TO_FN.  */
 115       DECL_ABSTRACT (copy) = 0;
 116       lang_hooks.dup_lang_specific_decl (copy);
 117
 118       /* TREE_ADDRESSABLE isn't used to indicate that a label's
 119          address has been taken; it's for internal bookkeeping in
 120          expand_goto_internal.  */
 121       if (TREE_CODE (copy) == LABEL_DECL)
 122         {
 123           TREE_ADDRESSABLE (copy) = 0;
 124         }
 125     }
 126
 127   /* Don't generate debug information for the copy if we wouldn't have
 128      generated it for the copy either.  */
 129   DECL_ARTIFICIAL (copy) = DECL_ARTIFICIAL (decl);
 130   DECL_IGNORED_P (copy) = DECL_IGNORED_P (decl);
 131
 132   /* Set the DECL_ABSTRACT_ORIGIN so the debugging routines know what
 133      declaration inspired this copy.  */
 134   DECL_ABSTRACT_ORIGIN (copy) = DECL_ORIGIN (decl);
 135
 136   /* The new variable/label has no RTL, yet.  */
 137   if (!TREE_STATIC (copy) && !DECL_EXTERNAL (copy))
 138     SET_DECL_RTL (copy, NULL_RTX);
 139
 140   /* These args would always appear unused, if not for this.  */
 141   TREE_USED (copy) = 1;
 142
 143   /* Set the context for the new declaration.  */
 144   if (!DECL_CONTEXT (decl))
 145     /* Globals stay global.  */
 146     ;
 147   else if (DECL_CONTEXT (decl) != from_fn)
 148     /* Things that weren't in the scope of the function we're inlining
 149        from aren't in the scope we're inlining to, either.  */
 150     ;
 151   else if (TREE_STATIC (decl))
 152     /* Function-scoped static variables should stay in the original
 153        function.  */
 154     ;
 155   else
 156     /* Ordinary automatic local variables are now in the scope of the
 157        new function.  */
 158     DECL_CONTEXT (copy) = to_fn;
 159
 160   return copy;
 161 }
 162
 163 \f
 164 /* Given a pointer to some BLOCK node, if the BLOCK_ABSTRACT_ORIGIN for the
 165    given BLOCK node is NULL, set the BLOCK_ABSTRACT_ORIGIN for the node so
 166    that it points to the node itself, thus indicating that the node is its
 167    own (abstract) origin.  Additionally, if the BLOCK_ABSTRACT_ORIGIN for
 168    the given node is NULL, recursively descend the decl/block tree which
 169    it is the root of, and for each other ..._DECL or BLOCK node contained
 170    therein whose DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also
 171    still NULL, set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN
 172    values to point to themselves.  */
 173
 174 static void
 175 set_block_origin_self (tree stmt)
 176 {
 177   if (BLOCK_ABSTRACT_ORIGIN (stmt) == NULL_TREE)
 178     {
 179       BLOCK_ABSTRACT_ORIGIN (stmt) = stmt;
 180
 181       {
 182         tree local_decl;
 183
 184         for (local_decl = BLOCK_VARS (stmt);
 185              local_decl != NULL_TREE;
 186              local_decl = TREE_CHAIN (local_decl))
 187           set_decl_origin_self (local_decl);    /* Potential recursion.  */
 188       }
 189
 190       {
 191         tree subblock;
 192
 193         for (subblock = BLOCK_SUBBLOCKS (stmt);
 194              subblock != NULL_TREE;
 195              subblock = BLOCK_CHAIN (subblock))
 196           set_block_origin_self (subblock);     /* Recurse.  */
 197       }
 198     }
 199 }
 200
 201 /* Given a pointer to some ..._DECL node, if the DECL_ABSTRACT_ORIGIN for
 202    the given ..._DECL node is NULL, set the DECL_ABSTRACT_ORIGIN for the
 203    node to so that it points to the node itself, thus indicating that the
 204    node represents its own (abstract) origin.  Additionally, if the
 205    DECL_ABSTRACT_ORIGIN for the given node is NULL, recursively descend
 206    the decl/block tree of which the given node is the root of, and for
 207    each other ..._DECL or BLOCK node contained therein whose
 208    DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also still NULL,
 209    set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN values to
 210    point to themselves.  */
 211
 212 void
 213 set_decl_origin_self (tree decl)
 214 {
 215   if (DECL_ABSTRACT_ORIGIN (decl) == NULL_TREE)
 216     {
 217       DECL_ABSTRACT_ORIGIN (decl) = decl;
 218       if (TREE_CODE (decl) == FUNCTION_DECL)
 219         {
 220           tree arg;
 221
 222           for (arg = DECL_ARGUMENTS (decl); arg; arg = TREE_CHAIN (arg))
 223             DECL_ABSTRACT_ORIGIN (arg) = arg;
 224           if (DECL_INITIAL (decl) != NULL_TREE
 225               && DECL_INITIAL (decl) != error_mark_node)
 226             set_block_origin_self (DECL_INITIAL (decl));
 227         }
 228     }
 229 }
 230 \f
 231 /* Given a pointer to some BLOCK node, and a boolean value to set the
 232    "abstract" flags to, set that value into the BLOCK_ABSTRACT flag for
 233    the given block, and for all local decls and all local sub-blocks
 234    (recursively) which are contained therein.  */
 235
 236 static void
 237 set_block_abstract_flags (tree stmt, int setting)
 238 {
 239   tree local_decl;
 240   tree subblock;
 241
 242   BLOCK_ABSTRACT (stmt) = setting;
 243
 244   for (local_decl = BLOCK_VARS (stmt);
 245        local_decl != NULL_TREE;
 246        local_decl = TREE_CHAIN (local_decl))
 247     set_decl_abstract_flags (local_decl, setting);
 248
 249   for (subblock = BLOCK_SUBBLOCKS (stmt);
 250        subblock != NULL_TREE;
 251        subblock = BLOCK_CHAIN (subblock))
 252     set_block_abstract_flags (subblock, setting);
 253 }
 254
 255 /* Given a pointer to some ..._DECL node, and a boolean value to set the
 256    "abstract" flags to, set that value into the DECL_ABSTRACT flag for the
 257    given decl, and (in the case where the decl is a FUNCTION_DECL) also
 258    set the abstract flags for all of the parameters, local vars, local
 259    blocks and sub-blocks (recursively) to the same setting.  */
 260
 261 void
 262 set_decl_abstract_flags (tree decl, int setting)
 263 {
 264   DECL_ABSTRACT (decl) = setting;
 265   if (TREE_CODE (decl) == FUNCTION_DECL)
 266     {
 267       tree arg;
 268
 269       for (arg = DECL_ARGUMENTS (decl); arg; arg = TREE_CHAIN (arg))
 270         DECL_ABSTRACT (arg) = setting;
 271       if (DECL_INITIAL (decl) != NULL_TREE
 272           && DECL_INITIAL (decl) != error_mark_node)
 273         set_block_abstract_flags (DECL_INITIAL (decl), setting);
 274     }
 275 }
 276 \f
 277 /* Functions to keep track of the values hard regs had at the start of
 278    the function.  */
 279
 280 rtx
 281 get_hard_reg_initial_reg (struct function *fun, rtx reg)
 282 {
 283   struct initial_value_struct *ivs = fun->hard_reg_initial_vals;
 284   int i;
 285
 286   if (ivs == 0)
 287     return NULL_RTX;
 288
 289   for (i = 0; i < ivs->num_entries; i++)
 290     if (rtx_equal_p (ivs->entries[i].pseudo, reg))
 291       return ivs->entries[i].hard_reg;
 292
 293   return NULL_RTX;
 294 }
 295
 296 /* Make sure that there's a pseudo register of mode MODE that stores the
 297    initial value of hard register REGNO.  Return an rtx for such a pseudo.  */
 298
 299 rtx
 300 get_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 301 {
 302   struct initial_value_struct *ivs;
 303   rtx rv;
 304
 305   rv = has_hard_reg_initial_val (mode, regno);
 306   if (rv)
 307     return rv;
 308
 309   ivs = cfun->hard_reg_initial_vals;
 310   if (ivs == 0)
 311     {
 312       ivs = ggc_alloc (sizeof (initial_value_struct));
 313       ivs->num_entries = 0;
 314       ivs->max_entries = 5;
 315       ivs->entries = ggc_alloc (5 * sizeof (initial_value_pair));
 316       cfun->hard_reg_initial_vals = ivs;
 317     }
 318
 319   if (ivs->num_entries >= ivs->max_entries)
 320     {
 321       ivs->max_entries += 5;
 322       ivs->entries = ggc_realloc (ivs->entries,
 323                                   ivs->max_entries
 324                                   * sizeof (initial_value_pair));
 325     }
 326
 327   ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
 328   ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
 329
 330   return ivs->entries[ivs->num_entries++].pseudo;
 331 }
 332
 333 /* See if get_hard_reg_initial_val has been used to create a pseudo
 334    for the initial value of hard register REGNO in mode MODE.  Return
 335    the associated pseudo if so, otherwise return NULL.  */
 336
 337 rtx
 338 has_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 339 {
 340   struct initial_value_struct *ivs;
 341   int i;
 342
 343   ivs = cfun->hard_reg_initial_vals;
 344   if (ivs != 0)
 345     for (i = 0; i < ivs->num_entries; i++)
 346       if (GET_MODE (ivs->entries[i].hard_reg) == mode
 347           && REGNO (ivs->entries[i].hard_reg) == regno)
 348         return ivs->entries[i].pseudo;
 349
 350   return NULL_RTX;
 351 }
 352
 353 void
 354 emit_initial_value_sets (void)
 355 {
 356   struct initial_value_struct *ivs = cfun->hard_reg_initial_vals;
 357   int i;
 358   rtx seq;
 359
 360   if (ivs == 0)
 361     return;
 362
 363   start_sequence ();
 364   for (i = 0; i < ivs->num_entries; i++)
 365     emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
 366   seq = get_insns ();
 367   end_sequence ();
 368
 369   emit_insn_after (seq, entry_of_function ());
 370 }
 371
 372 /* If the backend knows where to allocate pseudos for hard
 373    register initial values, register these allocations now.  */
 374 void
 375 allocate_initial_values (rtx *reg_equiv_memory_loc ATTRIBUTE_UNUSED)
 376 {
 377 #ifdef ALLOCATE_INITIAL_VALUE
 378   struct initial_value_struct *ivs = cfun->hard_reg_initial_vals;
 379   int i;
 380
 381   if (ivs == 0)
 382     return;
 383
 384   for (i = 0; i < ivs->num_entries; i++)
 385     {
 386       int regno = REGNO (ivs->entries[i].pseudo);
 387       rtx x = ALLOCATE_INITIAL_VALUE (ivs->entries[i].hard_reg);
 388
 389       if (x && REG_N_SETS (REGNO (ivs->entries[i].pseudo)) <= 1)
 390         {
 391           if (MEM_P (x))
 392             reg_equiv_memory_loc[regno] = x;
 393           else
 394             {
 395               basic_block bb;
 396               int new_regno;
 397
 398               gcc_assert (REG_P (x));
 399               new_regno = REGNO (x);
 400               reg_renumber[regno] = new_regno;
 401               /* Poke the regno right into regno_reg_rtx so that even
 402                  fixed regs are accepted.  */
 403               REGNO (ivs->entries[i].pseudo) = new_regno;
 404               /* Update global register liveness information.  */
 405               FOR_EACH_BB (bb)
 406                 {
 407                   if (REGNO_REG_SET_P(bb->global_live_at_start, regno))
 408                     SET_REGNO_REG_SET (bb->global_live_at_start, new_regno);
 409                   if (REGNO_REG_SET_P(bb->global_live_at_end, regno))
 410                     SET_REGNO_REG_SET (bb->global_live_at_end, new_regno);
 411                 }
 412             }
 413         }
 414     }
 415 #endif
 416 }
 417
 418 #include "gt-integrate.h"