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, 2006, 2007, 2008, 2009
   4    Free Software Foundation, Inc.
   5    Contributed by Michael Tiemann (tiemann@cygnus.com)
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify it under
  10 the terms of the GNU General Public License as published by the Free
  11 Software Foundation; either version 3, or (at your option) any later
  12 version.
  13
  14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17 for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING3.  If not see
  21 <http://www.gnu.org/licenses/>.  */
  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 "except.h"
  40 #include "function.h"
  41 #include "toplev.h"
  42 #include "intl.h"
  43 #include "params.h"
  44 #include "ggc.h"
  45 #include "target.h"
  46 #include "langhooks.h"
  47 #include "tree-pass.h"
  48 #include "df.h"
  49
  50 /* Round to the next highest integer that meets the alignment.  */
  51 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
  52 \f
  53
  54 /* Private type used by {get/has}_hard_reg_initial_val.  */
  55 typedef struct GTY(()) initial_value_pair {
  56   rtx hard_reg;
  57   rtx pseudo;
  58 } initial_value_pair;
  59 typedef struct GTY(()) initial_value_struct {
  60   int num_entries;
  61   int max_entries;
  62   initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
  63 } initial_value_struct;
  64
  65 static void set_block_origin_self (tree);
  66 static void set_block_abstract_flags (tree, int);
  67 \f
  68
  69 /* Return false if the function FNDECL cannot be inlined on account of its
  70    attributes, true otherwise.  */
  71 bool
  72 function_attribute_inlinable_p (const_tree fndecl)
  73 {
  74   if (targetm.attribute_table)
  75     {
  76       const_tree a;
  77
  78       for (a = DECL_ATTRIBUTES (fndecl); a; a = TREE_CHAIN (a))
  79         {
  80           const_tree name = TREE_PURPOSE (a);
  81           int i;
  82
  83           for (i = 0; targetm.attribute_table[i].name != NULL; i++)
  84             if (is_attribute_p (targetm.attribute_table[i].name, name))
  85               return targetm.function_attribute_inlinable_p (fndecl);
  86         }
  87     }
  88
  89   return true;
  90 }
  91 \f
  92 /* Given a pointer to some BLOCK node, if the BLOCK_ABSTRACT_ORIGIN for the
  93    given BLOCK node is NULL, set the BLOCK_ABSTRACT_ORIGIN for the node so
  94    that it points to the node itself, thus indicating that the node is its
  95    own (abstract) origin.  Additionally, if the BLOCK_ABSTRACT_ORIGIN for
  96    the given node is NULL, recursively descend the decl/block tree which
  97    it is the root of, and for each other ..._DECL or BLOCK node contained
  98    therein whose DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also
  99    still NULL, set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN
 100    values to point to themselves.  */
 101
 102 static void
 103 set_block_origin_self (tree stmt)
 104 {
 105   if (BLOCK_ABSTRACT_ORIGIN (stmt) == NULL_TREE)
 106     {
 107       BLOCK_ABSTRACT_ORIGIN (stmt) = stmt;
 108
 109       {
 110         tree local_decl;
 111
 112         for (local_decl = BLOCK_VARS (stmt);
 113              local_decl != NULL_TREE;
 114              local_decl = TREE_CHAIN (local_decl))
 115           set_decl_origin_self (local_decl);    /* Potential recursion.  */
 116       }
 117
 118       {
 119         tree subblock;
 120
 121         for (subblock = BLOCK_SUBBLOCKS (stmt);
 122              subblock != NULL_TREE;
 123              subblock = BLOCK_CHAIN (subblock))
 124           set_block_origin_self (subblock);     /* Recurse.  */
 125       }
 126     }
 127 }
 128
 129 /* Given a pointer to some ..._DECL node, if the DECL_ABSTRACT_ORIGIN for
 130    the given ..._DECL node is NULL, set the DECL_ABSTRACT_ORIGIN for the
 131    node to so that it points to the node itself, thus indicating that the
 132    node represents its own (abstract) origin.  Additionally, if the
 133    DECL_ABSTRACT_ORIGIN for the given node is NULL, recursively descend
 134    the decl/block tree of which the given node is the root of, and for
 135    each other ..._DECL or BLOCK node contained therein whose
 136    DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also still NULL,
 137    set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN values to
 138    point to themselves.  */
 139
 140 void
 141 set_decl_origin_self (tree decl)
 142 {
 143   if (DECL_ABSTRACT_ORIGIN (decl) == NULL_TREE)
 144     {
 145       DECL_ABSTRACT_ORIGIN (decl) = decl;
 146       if (TREE_CODE (decl) == FUNCTION_DECL)
 147         {
 148           tree arg;
 149
 150           for (arg = DECL_ARGUMENTS (decl); arg; arg = TREE_CHAIN (arg))
 151             DECL_ABSTRACT_ORIGIN (arg) = arg;
 152           if (DECL_INITIAL (decl) != NULL_TREE
 153               && DECL_INITIAL (decl) != error_mark_node)
 154             set_block_origin_self (DECL_INITIAL (decl));
 155         }
 156     }
 157 }
 158 \f
 159 /* Given a pointer to some BLOCK node, and a boolean value to set the
 160    "abstract" flags to, set that value into the BLOCK_ABSTRACT flag for
 161    the given block, and for all local decls and all local sub-blocks
 162    (recursively) which are contained therein.  */
 163
 164 static void
 165 set_block_abstract_flags (tree stmt, int setting)
 166 {
 167   tree local_decl;
 168   tree subblock;
 169   unsigned int i;
 170
 171   BLOCK_ABSTRACT (stmt) = setting;
 172
 173   for (local_decl = BLOCK_VARS (stmt);
 174        local_decl != NULL_TREE;
 175        local_decl = TREE_CHAIN (local_decl))
 176     set_decl_abstract_flags (local_decl, setting);
 177
 178   for (i = 0; i < BLOCK_NUM_NONLOCALIZED_VARS (stmt); i++)
 179     {
 180       local_decl = BLOCK_NONLOCALIZED_VAR (stmt, i);
 181       if ((TREE_CODE (local_decl) == VAR_DECL && !TREE_STATIC (local_decl))
 182           || TREE_CODE (local_decl) == PARM_DECL)
 183         set_decl_abstract_flags (local_decl, setting);
 184     }
 185
 186   for (subblock = BLOCK_SUBBLOCKS (stmt);
 187        subblock != NULL_TREE;
 188        subblock = BLOCK_CHAIN (subblock))
 189     set_block_abstract_flags (subblock, setting);
 190 }
 191
 192 /* Given a pointer to some ..._DECL node, and a boolean value to set the
 193    "abstract" flags to, set that value into the DECL_ABSTRACT flag for the
 194    given decl, and (in the case where the decl is a FUNCTION_DECL) also
 195    set the abstract flags for all of the parameters, local vars, local
 196    blocks and sub-blocks (recursively) to the same setting.  */
 197
 198 void
 199 set_decl_abstract_flags (tree decl, int setting)
 200 {
 201   DECL_ABSTRACT (decl) = setting;
 202   if (TREE_CODE (decl) == FUNCTION_DECL)
 203     {
 204       tree arg;
 205
 206       for (arg = DECL_ARGUMENTS (decl); arg; arg = TREE_CHAIN (arg))
 207         DECL_ABSTRACT (arg) = setting;
 208       if (DECL_INITIAL (decl) != NULL_TREE
 209           && DECL_INITIAL (decl) != error_mark_node)
 210         set_block_abstract_flags (DECL_INITIAL (decl), setting);
 211     }
 212 }
 213 \f
 214 /* Functions to keep track of the values hard regs had at the start of
 215    the function.  */
 216
 217 rtx
 218 get_hard_reg_initial_reg (rtx reg)
 219 {
 220   struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
 221   int i;
 222
 223   if (ivs == 0)
 224     return NULL_RTX;
 225
 226   for (i = 0; i < ivs->num_entries; i++)
 227     if (rtx_equal_p (ivs->entries[i].pseudo, reg))
 228       return ivs->entries[i].hard_reg;
 229
 230   return NULL_RTX;
 231 }
 232
 233 /* Make sure that there's a pseudo register of mode MODE that stores the
 234    initial value of hard register REGNO.  Return an rtx for such a pseudo.  */
 235
 236 rtx
 237 get_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 238 {
 239   struct initial_value_struct *ivs;
 240   rtx rv;
 241
 242   rv = has_hard_reg_initial_val (mode, regno);
 243   if (rv)
 244     return rv;
 245
 246   ivs = crtl->hard_reg_initial_vals;
 247   if (ivs == 0)
 248     {
 249       ivs = ggc_alloc_initial_value_struct ();
 250       ivs->num_entries = 0;
 251       ivs->max_entries = 5;
 252       ivs->entries = ggc_alloc_vec_initial_value_pair (5);
 253       crtl->hard_reg_initial_vals = ivs;
 254     }
 255
 256   if (ivs->num_entries >= ivs->max_entries)
 257     {
 258       ivs->max_entries += 5;
 259       ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
 260                                     ivs->max_entries);
 261     }
 262
 263   ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
 264   ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
 265
 266   return ivs->entries[ivs->num_entries++].pseudo;
 267 }
 268
 269 /* See if get_hard_reg_initial_val has been used to create a pseudo
 270    for the initial value of hard register REGNO in mode MODE.  Return
 271    the associated pseudo if so, otherwise return NULL.  */
 272
 273 rtx
 274 has_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 275 {
 276   struct initial_value_struct *ivs;
 277   int i;
 278
 279   ivs = crtl->hard_reg_initial_vals;
 280   if (ivs != 0)
 281     for (i = 0; i < ivs->num_entries; i++)
 282       if (GET_MODE (ivs->entries[i].hard_reg) == mode
 283           && REGNO (ivs->entries[i].hard_reg) == regno)
 284         return ivs->entries[i].pseudo;
 285
 286   return NULL_RTX;
 287 }
 288
 289 unsigned int
 290 emit_initial_value_sets (void)
 291 {
 292   struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
 293   int i;
 294   rtx seq;
 295
 296   if (ivs == 0)
 297     return 0;
 298
 299   start_sequence ();
 300   for (i = 0; i < ivs->num_entries; i++)
 301     emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
 302   seq = get_insns ();
 303   end_sequence ();
 304
 305   emit_insn_at_entry (seq);
 306   return 0;
 307 }
 308
 309 struct rtl_opt_pass pass_initial_value_sets =
 310 {
 311  {
 312   RTL_PASS,
 313   "initvals",                           /* name */
 314   NULL,                                 /* gate */
 315   emit_initial_value_sets,              /* execute */
 316   NULL,                                 /* sub */
 317   NULL,                                 /* next */
 318   0,                                    /* static_pass_number */
 319   TV_NONE,                              /* tv_id */
 320   0,                                    /* properties_required */
 321   0,                                    /* properties_provided */
 322   0,                                    /* properties_destroyed */
 323   0,                                    /* todo_flags_start */
 324   TODO_dump_func                        /* todo_flags_finish */
 325  }
 326 };
 327
 328 /* If the backend knows where to allocate pseudos for hard
 329    register initial values, register these allocations now.  */
 330 void
 331 allocate_initial_values (rtx *reg_equiv_memory_loc)
 332 {
 333   if (targetm.allocate_initial_value)
 334     {
 335       struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
 336       int i;
 337
 338       if (ivs == 0)
 339         return;
 340
 341       for (i = 0; i < ivs->num_entries; i++)
 342         {
 343           int regno = REGNO (ivs->entries[i].pseudo);
 344           rtx x = targetm.allocate_initial_value (ivs->entries[i].hard_reg);
 345
 346           if (x && REG_N_SETS (REGNO (ivs->entries[i].pseudo)) <= 1)
 347             {
 348               if (MEM_P (x))
 349                 reg_equiv_memory_loc[regno] = x;
 350               else
 351                 {
 352                   basic_block bb;
 353                   int new_regno;
 354
 355                   gcc_assert (REG_P (x));
 356                   new_regno = REGNO (x);
 357                   reg_renumber[regno] = new_regno;
 358                   /* Poke the regno right into regno_reg_rtx so that even
 359                      fixed regs are accepted.  */
 360                   SET_REGNO (ivs->entries[i].pseudo, new_regno);
 361                   /* Update global register liveness information.  */
 362                   FOR_EACH_BB (bb)
 363                     {
 364                       if (REGNO_REG_SET_P(df_get_live_in (bb), regno))
 365                         SET_REGNO_REG_SET (df_get_live_in (bb), new_regno);
 366                       if (REGNO_REG_SET_P(df_get_live_out (bb), regno))
 367                         SET_REGNO_REG_SET (df_get_live_out (bb), new_regno);
 368                     }
 369                 }
 370             }
 371         }
 372     }
 373 }
 374
 375 #include "gt-integrate.h"