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           LABEL_DECL_UID (copy) = -1;
 125         }
 126     }
 127
 128   /* Don't generate debug information for the copy if we wouldn't have
 129      generated it for the copy either.  */
 130   DECL_ARTIFICIAL (copy) = DECL_ARTIFICIAL (decl);
 131   DECL_IGNORED_P (copy) = DECL_IGNORED_P (decl);
 132
 133   /* Set the DECL_ABSTRACT_ORIGIN so the debugging routines know what
 134      declaration inspired this copy.  */
 135   DECL_ABSTRACT_ORIGIN (copy) = DECL_ORIGIN (decl);
 136
 137   /* The new variable/label has no RTL, yet.  */
 138   if (!TREE_STATIC (copy) && !DECL_EXTERNAL (copy))
 139     SET_DECL_RTL (copy, NULL_RTX);
 140
 141   /* These args would always appear unused, if not for this.  */
 142   TREE_USED (copy) = 1;
 143
 144   /* Set the context for the new declaration.  */
 145   if (!DECL_CONTEXT (decl))
 146     /* Globals stay global.  */
 147     ;
 148   else if (DECL_CONTEXT (decl) != from_fn)
 149     /* Things that weren't in the scope of the function we're inlining
 150        from aren't in the scope we're inlining to, either.  */
 151     ;
 152   else if (TREE_STATIC (decl))
 153     /* Function-scoped static variables should stay in the original
 154        function.  */
 155     ;
 156   else
 157     /* Ordinary automatic local variables are now in the scope of the
 158        new function.  */
 159     DECL_CONTEXT (copy) = to_fn;
 160
 161   return copy;
 162 }
 163
 164 \f
 165 /* Given a pointer to some BLOCK node, if the BLOCK_ABSTRACT_ORIGIN for the
 166    given BLOCK node is NULL, set the BLOCK_ABSTRACT_ORIGIN for the node so
 167    that it points to the node itself, thus indicating that the node is its
 168    own (abstract) origin.  Additionally, if the BLOCK_ABSTRACT_ORIGIN for
 169    the given node is NULL, recursively descend the decl/block tree which
 170    it is the root of, and for each other ..._DECL or BLOCK node contained
 171    therein whose DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also
 172    still NULL, set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN
 173    values to point to themselves.  */
 174
 175 static void
 176 set_block_origin_self (tree stmt)
 177 {
 178   if (BLOCK_ABSTRACT_ORIGIN (stmt) == NULL_TREE)
 179     {
 180       BLOCK_ABSTRACT_ORIGIN (stmt) = stmt;
 181
 182       {
 183         tree local_decl;
 184
 185         for (local_decl = BLOCK_VARS (stmt);
 186              local_decl != NULL_TREE;
 187              local_decl = TREE_CHAIN (local_decl))
 188           set_decl_origin_self (local_decl);    /* Potential recursion.  */
 189       }
 190
 191       {
 192         tree subblock;
 193
 194         for (subblock = BLOCK_SUBBLOCKS (stmt);
 195              subblock != NULL_TREE;
 196              subblock = BLOCK_CHAIN (subblock))
 197           set_block_origin_self (subblock);     /* Recurse.  */
 198       }
 199     }
 200 }
 201
 202 /* Given a pointer to some ..._DECL node, if the DECL_ABSTRACT_ORIGIN for
 203    the given ..._DECL node is NULL, set the DECL_ABSTRACT_ORIGIN for the
 204    node to so that it points to the node itself, thus indicating that the
 205    node represents its own (abstract) origin.  Additionally, if the
 206    DECL_ABSTRACT_ORIGIN for the given node is NULL, recursively descend
 207    the decl/block tree of which the given node is the root of, and for
 208    each other ..._DECL or BLOCK node contained therein whose
 209    DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also still NULL,
 210    set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN values to
 211    point to themselves.  */
 212
 213 void
 214 set_decl_origin_self (tree decl)
 215 {
 216   if (DECL_ABSTRACT_ORIGIN (decl) == NULL_TREE)
 217     {
 218       DECL_ABSTRACT_ORIGIN (decl) = decl;
 219       if (TREE_CODE (decl) == FUNCTION_DECL)
 220         {
 221           tree arg;
 222
 223           for (arg = DECL_ARGUMENTS (decl); arg; arg = TREE_CHAIN (arg))
 224             DECL_ABSTRACT_ORIGIN (arg) = arg;
 225           if (DECL_INITIAL (decl) != NULL_TREE
 226               && DECL_INITIAL (decl) != error_mark_node)
 227             set_block_origin_self (DECL_INITIAL (decl));
 228         }
 229     }
 230 }
 231 \f
 232 /* Given a pointer to some BLOCK node, and a boolean value to set the
 233    "abstract" flags to, set that value into the BLOCK_ABSTRACT flag for
 234    the given block, and for all local decls and all local sub-blocks
 235    (recursively) which are contained therein.  */
 236
 237 static void
 238 set_block_abstract_flags (tree stmt, int setting)
 239 {
 240   tree local_decl;
 241   tree subblock;
 242
 243   BLOCK_ABSTRACT (stmt) = setting;
 244
 245   for (local_decl = BLOCK_VARS (stmt);
 246        local_decl != NULL_TREE;
 247        local_decl = TREE_CHAIN (local_decl))
 248     set_decl_abstract_flags (local_decl, setting);
 249
 250   for (subblock = BLOCK_SUBBLOCKS (stmt);
 251        subblock != NULL_TREE;
 252        subblock = BLOCK_CHAIN (subblock))
 253     set_block_abstract_flags (subblock, setting);
 254 }
 255
 256 /* Given a pointer to some ..._DECL node, and a boolean value to set the
 257    "abstract" flags to, set that value into the DECL_ABSTRACT flag for the
 258    given decl, and (in the case where the decl is a FUNCTION_DECL) also
 259    set the abstract flags for all of the parameters, local vars, local
 260    blocks and sub-blocks (recursively) to the same setting.  */
 261
 262 void
 263 set_decl_abstract_flags (tree decl, int setting)
 264 {
 265   DECL_ABSTRACT (decl) = setting;
 266   if (TREE_CODE (decl) == FUNCTION_DECL)
 267     {
 268       tree arg;
 269
 270       for (arg = DECL_ARGUMENTS (decl); arg; arg = TREE_CHAIN (arg))
 271         DECL_ABSTRACT (arg) = setting;
 272       if (DECL_INITIAL (decl) != NULL_TREE
 273           && DECL_INITIAL (decl) != error_mark_node)
 274         set_block_abstract_flags (DECL_INITIAL (decl), setting);
 275     }
 276 }
 277 \f
 278 /* Functions to keep track of the values hard regs had at the start of
 279    the function.  */
 280
 281 rtx
 282 get_hard_reg_initial_reg (struct function *fun, rtx reg)
 283 {
 284   struct initial_value_struct *ivs = fun->hard_reg_initial_vals;
 285   int i;
 286
 287   if (ivs == 0)
 288     return NULL_RTX;
 289
 290   for (i = 0; i < ivs->num_entries; i++)
 291     if (rtx_equal_p (ivs->entries[i].pseudo, reg))
 292       return ivs->entries[i].hard_reg;
 293
 294   return NULL_RTX;
 295 }
 296
 297 /* Make sure that there's a pseudo register of mode MODE that stores the
 298    initial value of hard register REGNO.  Return an rtx for such a pseudo.  */
 299
 300 rtx
 301 get_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 302 {
 303   struct initial_value_struct *ivs;
 304   rtx rv;
 305
 306   rv = has_hard_reg_initial_val (mode, regno);
 307   if (rv)
 308     return rv;
 309
 310   ivs = cfun->hard_reg_initial_vals;
 311   if (ivs == 0)
 312     {
 313       ivs = ggc_alloc (sizeof (initial_value_struct));
 314       ivs->num_entries = 0;
 315       ivs->max_entries = 5;
 316       ivs->entries = ggc_alloc (5 * sizeof (initial_value_pair));
 317       cfun->hard_reg_initial_vals = ivs;
 318     }
 319
 320   if (ivs->num_entries >= ivs->max_entries)
 321     {
 322       ivs->max_entries += 5;
 323       ivs->entries = ggc_realloc (ivs->entries,
 324                                   ivs->max_entries
 325                                   * sizeof (initial_value_pair));
 326     }
 327
 328   ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
 329   ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
 330
 331   return ivs->entries[ivs->num_entries++].pseudo;
 332 }
 333
 334 /* See if get_hard_reg_initial_val has been used to create a pseudo
 335    for the initial value of hard register REGNO in mode MODE.  Return
 336    the associated pseudo if so, otherwise return NULL.  */
 337
 338 rtx
 339 has_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 340 {
 341   struct initial_value_struct *ivs;
 342   int i;
 343
 344   ivs = cfun->hard_reg_initial_vals;
 345   if (ivs != 0)
 346     for (i = 0; i < ivs->num_entries; i++)
 347       if (GET_MODE (ivs->entries[i].hard_reg) == mode
 348           && REGNO (ivs->entries[i].hard_reg) == regno)
 349         return ivs->entries[i].pseudo;
 350
 351   return NULL_RTX;
 352 }
 353
 354 void
 355 emit_initial_value_sets (void)
 356 {
 357   struct initial_value_struct *ivs = cfun->hard_reg_initial_vals;
 358   int i;
 359   rtx seq;
 360
 361   if (ivs == 0)
 362     return;
 363
 364   start_sequence ();
 365   for (i = 0; i < ivs->num_entries; i++)
 366     emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
 367   seq = get_insns ();
 368   end_sequence ();
 369
 370   emit_insn_after (seq, entry_of_function ());
 371 }
 372
 373 /* If the backend knows where to allocate pseudos for hard
 374    register initial values, register these allocations now.  */
 375 void
 376 allocate_initial_values (rtx *reg_equiv_memory_loc ATTRIBUTE_UNUSED)
 377 {
 378 #ifdef ALLOCATE_INITIAL_VALUE
 379   struct initial_value_struct *ivs = cfun->hard_reg_initial_vals;
 380   int i;
 381
 382   if (ivs == 0)
 383     return;
 384
 385   for (i = 0; i < ivs->num_entries; i++)
 386     {
 387       int regno = REGNO (ivs->entries[i].pseudo);
 388       rtx x = ALLOCATE_INITIAL_VALUE (ivs->entries[i].hard_reg);
 389
 390       if (x && REG_N_SETS (REGNO (ivs->entries[i].pseudo)) <= 1)
 391         {
 392           if (MEM_P (x))
 393             reg_equiv_memory_loc[regno] = x;
 394           else
 395             {
 396               basic_block bb;
 397               int new_regno;
 398
 399               gcc_assert (REG_P (x));
 400               new_regno = REGNO (x);
 401               reg_renumber[regno] = new_regno;
 402               /* Poke the regno right into regno_reg_rtx so that even
 403                  fixed regs are accepted.  */
 404               REGNO (ivs->entries[i].pseudo) = new_regno;
 405               /* Update global register liveness information.  */
 406               FOR_EACH_BB (bb)
 407                 {
 408                   if (REGNO_REG_SET_P(bb->global_live_at_start, regno))
 409                     SET_REGNO_REG_SET (bb->global_live_at_start, new_regno);
 410                   if (REGNO_REG_SET_P(bb->global_live_at_end, regno))
 411                     SET_REGNO_REG_SET (bb->global_live_at_end, new_regno);
 412                 }
 413             }
 414         }
 415     }
 416 #endif
 417 }
 418
 419 #include "gt-integrate.h"