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, 2010, 2011
   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 "diagnostic-core.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 = DECL_CHAIN (local_decl))
 115           if (! DECL_EXTERNAL (local_decl))
 116             set_decl_origin_self (local_decl);  /* Potential recursion.  */
 117       }
 118
 119       {
 120         tree subblock;
 121
 122         for (subblock = BLOCK_SUBBLOCKS (stmt);
 123              subblock != NULL_TREE;
 124              subblock = BLOCK_CHAIN (subblock))
 125           set_block_origin_self (subblock);     /* Recurse.  */
 126       }
 127     }
 128 }
 129
 130 /* Given a pointer to some ..._DECL node, if the DECL_ABSTRACT_ORIGIN for
 131    the given ..._DECL node is NULL, set the DECL_ABSTRACT_ORIGIN for the
 132    node to so that it points to the node itself, thus indicating that the
 133    node represents its own (abstract) origin.  Additionally, if the
 134    DECL_ABSTRACT_ORIGIN for the given node is NULL, recursively descend
 135    the decl/block tree of which the given node is the root of, and for
 136    each other ..._DECL or BLOCK node contained therein whose
 137    DECL_ABSTRACT_ORIGINs or BLOCK_ABSTRACT_ORIGINs are also still NULL,
 138    set *their* DECL_ABSTRACT_ORIGIN or BLOCK_ABSTRACT_ORIGIN values to
 139    point to themselves.  */
 140
 141 void
 142 set_decl_origin_self (tree decl)
 143 {
 144   if (DECL_ABSTRACT_ORIGIN (decl) == NULL_TREE)
 145     {
 146       DECL_ABSTRACT_ORIGIN (decl) = decl;
 147       if (TREE_CODE (decl) == FUNCTION_DECL)
 148         {
 149           tree arg;
 150
 151           for (arg = DECL_ARGUMENTS (decl); arg; arg = DECL_CHAIN (arg))
 152             DECL_ABSTRACT_ORIGIN (arg) = arg;
 153           if (DECL_INITIAL (decl) != NULL_TREE
 154               && DECL_INITIAL (decl) != error_mark_node)
 155             set_block_origin_self (DECL_INITIAL (decl));
 156         }
 157     }
 158 }
 159 \f
 160 /* Given a pointer to some BLOCK node, and a boolean value to set the
 161    "abstract" flags to, set that value into the BLOCK_ABSTRACT flag for
 162    the given block, and for all local decls and all local sub-blocks
 163    (recursively) which are contained therein.  */
 164
 165 static void
 166 set_block_abstract_flags (tree stmt, int setting)
 167 {
 168   tree local_decl;
 169   tree subblock;
 170   unsigned int i;
 171
 172   BLOCK_ABSTRACT (stmt) = setting;
 173
 174   for (local_decl = BLOCK_VARS (stmt);
 175        local_decl != NULL_TREE;
 176        local_decl = DECL_CHAIN (local_decl))
 177     if (! DECL_EXTERNAL (local_decl))
 178       set_decl_abstract_flags (local_decl, setting);
 179
 180   for (i = 0; i < BLOCK_NUM_NONLOCALIZED_VARS (stmt); i++)
 181     {
 182       local_decl = BLOCK_NONLOCALIZED_VAR (stmt, i);
 183       if ((TREE_CODE (local_decl) == VAR_DECL && !TREE_STATIC (local_decl))
 184           || TREE_CODE (local_decl) == PARM_DECL)
 185         set_decl_abstract_flags (local_decl, setting);
 186     }
 187
 188   for (subblock = BLOCK_SUBBLOCKS (stmt);
 189        subblock != NULL_TREE;
 190        subblock = BLOCK_CHAIN (subblock))
 191     set_block_abstract_flags (subblock, setting);
 192 }
 193
 194 /* Given a pointer to some ..._DECL node, and a boolean value to set the
 195    "abstract" flags to, set that value into the DECL_ABSTRACT flag for the
 196    given decl, and (in the case where the decl is a FUNCTION_DECL) also
 197    set the abstract flags for all of the parameters, local vars, local
 198    blocks and sub-blocks (recursively) to the same setting.  */
 199
 200 void
 201 set_decl_abstract_flags (tree decl, int setting)
 202 {
 203   DECL_ABSTRACT (decl) = setting;
 204   if (TREE_CODE (decl) == FUNCTION_DECL)
 205     {
 206       tree arg;
 207
 208       for (arg = DECL_ARGUMENTS (decl); arg; arg = DECL_CHAIN (arg))
 209         DECL_ABSTRACT (arg) = setting;
 210       if (DECL_INITIAL (decl) != NULL_TREE
 211           && DECL_INITIAL (decl) != error_mark_node)
 212         set_block_abstract_flags (DECL_INITIAL (decl), setting);
 213     }
 214 }
 215 \f
 216 /* Functions to keep track of the values hard regs had at the start of
 217    the function.  */
 218
 219 rtx
 220 get_hard_reg_initial_reg (rtx reg)
 221 {
 222   struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
 223   int i;
 224
 225   if (ivs == 0)
 226     return NULL_RTX;
 227
 228   for (i = 0; i < ivs->num_entries; i++)
 229     if (rtx_equal_p (ivs->entries[i].pseudo, reg))
 230       return ivs->entries[i].hard_reg;
 231
 232   return NULL_RTX;
 233 }
 234
 235 /* Make sure that there's a pseudo register of mode MODE that stores the
 236    initial value of hard register REGNO.  Return an rtx for such a pseudo.  */
 237
 238 rtx
 239 get_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 240 {
 241   struct initial_value_struct *ivs;
 242   rtx rv;
 243
 244   rv = has_hard_reg_initial_val (mode, regno);
 245   if (rv)
 246     return rv;
 247
 248   ivs = crtl->hard_reg_initial_vals;
 249   if (ivs == 0)
 250     {
 251       ivs = ggc_alloc_initial_value_struct ();
 252       ivs->num_entries = 0;
 253       ivs->max_entries = 5;
 254       ivs->entries = ggc_alloc_vec_initial_value_pair (5);
 255       crtl->hard_reg_initial_vals = ivs;
 256     }
 257
 258   if (ivs->num_entries >= ivs->max_entries)
 259     {
 260       ivs->max_entries += 5;
 261       ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
 262                                     ivs->max_entries);
 263     }
 264
 265   ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
 266   ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
 267
 268   return ivs->entries[ivs->num_entries++].pseudo;
 269 }
 270
 271 /* See if get_hard_reg_initial_val has been used to create a pseudo
 272    for the initial value of hard register REGNO in mode MODE.  Return
 273    the associated pseudo if so, otherwise return NULL.  */
 274
 275 rtx
 276 has_hard_reg_initial_val (enum machine_mode mode, unsigned int regno)
 277 {
 278   struct initial_value_struct *ivs;
 279   int i;
 280
 281   ivs = crtl->hard_reg_initial_vals;
 282   if (ivs != 0)
 283     for (i = 0; i < ivs->num_entries; i++)
 284       if (GET_MODE (ivs->entries[i].hard_reg) == mode
 285           && REGNO (ivs->entries[i].hard_reg) == regno)
 286         return ivs->entries[i].pseudo;
 287
 288   return NULL_RTX;
 289 }
 290
 291 unsigned int
 292 emit_initial_value_sets (void)
 293 {
 294   struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
 295   int i;
 296   rtx seq;
 297
 298   if (ivs == 0)
 299     return 0;
 300
 301   start_sequence ();
 302   for (i = 0; i < ivs->num_entries; i++)
 303     emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
 304   seq = get_insns ();
 305   end_sequence ();
 306
 307   emit_insn_at_entry (seq);
 308   return 0;
 309 }
 310
 311 struct rtl_opt_pass pass_initial_value_sets =
 312 {
 313  {
 314   RTL_PASS,
 315   "initvals",                           /* name */
 316   NULL,                                 /* gate */
 317   emit_initial_value_sets,              /* execute */
 318   NULL,                                 /* sub */
 319   NULL,                                 /* next */
 320   0,                                    /* static_pass_number */
 321   TV_NONE,                              /* tv_id */
 322   0,                                    /* properties_required */
 323   0,                                    /* properties_provided */
 324   0,                                    /* properties_destroyed */
 325   0,                                    /* todo_flags_start */
 326   TODO_dump_func                        /* todo_flags_finish */
 327  }
 328 };
 329
 330 /* If the backend knows where to allocate pseudos for hard
 331    register initial values, register these allocations now.  */
 332 void
 333 allocate_initial_values (rtx *reg_equiv_memory_loc)
 334 {
 335   if (targetm.allocate_initial_value)
 336     {
 337       struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
 338       int i;
 339
 340       if (ivs == 0)
 341         return;
 342
 343       for (i = 0; i < ivs->num_entries; i++)
 344         {
 345           int regno = REGNO (ivs->entries[i].pseudo);
 346           rtx x = targetm.allocate_initial_value (ivs->entries[i].hard_reg);
 347
 348           if (x && REG_N_SETS (REGNO (ivs->entries[i].pseudo)) <= 1)
 349             {
 350               if (MEM_P (x))
 351                 reg_equiv_memory_loc[regno] = x;
 352               else
 353                 {
 354                   basic_block bb;
 355                   int new_regno;
 356
 357                   gcc_assert (REG_P (x));
 358                   new_regno = REGNO (x);
 359                   reg_renumber[regno] = new_regno;
 360                   /* Poke the regno right into regno_reg_rtx so that even
 361                      fixed regs are accepted.  */
 362                   SET_REGNO (ivs->entries[i].pseudo, new_regno);
 363                   /* Update global register liveness information.  */
 364                   FOR_EACH_BB (bb)
 365                     {
 366                       if (REGNO_REG_SET_P(df_get_live_in (bb), regno))
 367                         SET_REGNO_REG_SET (df_get_live_in (bb), new_regno);
 368                       if (REGNO_REG_SET_P(df_get_live_out (bb), regno))
 369                         SET_REGNO_REG_SET (df_get_live_out (bb), new_regno);
 370                     }
 371                 }
 372             }
 373         }
 374     }
 375 }
 376
 377 #include "gt-integrate.h"