lra-lives.c 42.5 KB
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/* Build live ranges for pseudos.
Jakub Jelinek committed
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   Copyright (C) 2010-2015 Free Software Foundation, Inc.
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   Contributed by Vladimir Makarov <vmakarov@redhat.com>.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3.	If not see
<http://www.gnu.org/licenses/>.	 */


/* This file contains code to build pseudo live-ranges (analogous
   structures used in IRA, so read comments about the live-ranges
   there) and other info necessary for other passes to assign
   hard-registers to pseudos, coalesce the spilled pseudos, and assign
   stack memory slots to spilled pseudos.  */

#include "config.h"
#include "system.h"
#include "coretypes.h"
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#include "backend.h"
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#include "rtl.h"
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#include "tree.h"
#include "predict.h"
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#include "df.h"
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#include "tm_p.h"
#include "insn-config.h"
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#include "regs.h"
#include "ira.h"
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#include "recog.h"
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#include "cfganal.h"
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#include "sparseset.h"
#include "lra-int.h"

/* Program points are enumerated by numbers from range
   0..LRA_LIVE_MAX_POINT-1.  There are approximately two times more
   program points than insns.  Program points are places in the
   program where liveness info can be changed.	In most general case
   (there are more complicated cases too) some program points
   correspond to places where input operand dies and other ones
   correspond to places where output operands are born.	 */
int lra_live_max_point;

/* Accumulated execution frequency of all references for each hard
   register.  */
int lra_hard_reg_usage[FIRST_PSEUDO_REGISTER];

/* A global flag whose true value says to build live ranges for all
   pseudos, otherwise the live ranges only for pseudos got memory is
   build.  True value means also building copies and setting up hard
   register preferences.  The complete info is necessary only for the
   assignment pass.  The complete info is not needed for the
   coalescing and spill passes.	 */
static bool complete_info_p;

/* Pseudos live at current point in the RTL scan.  */
static sparseset pseudos_live;

/* Pseudos probably living through calls and setjumps.	As setjump is
   a call too, if a bit in PSEUDOS_LIVE_THROUGH_SETJUMPS is set up
   then the corresponding bit in PSEUDOS_LIVE_THROUGH_CALLS is set up
   too.	 These data are necessary for cases when only one subreg of a
   multi-reg pseudo is set up after a call.  So we decide it is
   probably live when traversing bb backward.  We are sure about
   living when we see its usage or definition of the pseudo.  */
static sparseset pseudos_live_through_calls;
static sparseset pseudos_live_through_setjumps;

/* Set of hard regs (except eliminable ones) currently live.  */
static HARD_REG_SET hard_regs_live;

/* Set of pseudos and hard registers start living/dying in the current
   insn.  These sets are used to update REG_DEAD and REG_UNUSED notes
   in the insn.	 */
static sparseset start_living, start_dying;

/* Set of pseudos and hard regs dead and unused in the current
   insn.  */
static sparseset unused_set, dead_set;

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/* Bitmap used for holding intermediate bitmap operation results.  */
static bitmap_head temp_bitmap;

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/* Pool for pseudo live ranges.	 */
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static object_allocator<lra_live_range> lra_live_range_pool ("live ranges");
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/* Free live range list LR.  */
static void
free_live_range_list (lra_live_range_t lr)
{
  lra_live_range_t next;

  while (lr != NULL)
    {
      next = lr->next;
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      lra_live_range_pool.remove (lr);
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      lr = next;
    }
}

/* Create and return pseudo live range with given attributes.  */
static lra_live_range_t
create_live_range (int regno, int start, int finish, lra_live_range_t next)
{
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  lra_live_range_t p = lra_live_range_pool.allocate ();
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  p->regno = regno;
  p->start = start;
  p->finish = finish;
  p->next = next;
  return p;
}

/* Copy live range R and return the result.  */
static lra_live_range_t
copy_live_range (lra_live_range_t r)
{
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  return new (lra_live_range_pool) lra_live_range (*r);
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}

/* Copy live range list given by its head R and return the result.  */
lra_live_range_t
lra_copy_live_range_list (lra_live_range_t r)
{
  lra_live_range_t p, first, *chain;

  first = NULL;
  for (chain = &first; r != NULL; r = r->next)
    {
      p = copy_live_range (r);
      *chain = p;
      chain = &p->next;
    }
  return first;
}

/* Merge *non-intersected* ranges R1 and R2 and returns the result.
   The function maintains the order of ranges and tries to minimize
   size of the result range list.  Ranges R1 and R2 may not be used
   after the call.  */
lra_live_range_t
lra_merge_live_ranges (lra_live_range_t r1, lra_live_range_t r2)
{
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  lra_live_range_t first, last;
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  if (r1 == NULL)
    return r2;
  if (r2 == NULL)
    return r1;
  for (first = last = NULL; r1 != NULL && r2 != NULL;)
    {
      if (r1->start < r2->start)
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	std::swap (r1, r2);

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      if (r1->start == r2->finish + 1)
	{
	  /* Joint ranges: merge r1 and r2 into r1.  */
	  r1->start = r2->start;
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	  lra_live_range_t temp = r2;
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	  r2 = r2->next;
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	  lra_live_range_pool.remove (temp);
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	}
      else
	{
	  gcc_assert (r2->finish + 1 < r1->start);
	  /* Add r1 to the result.  */
	  if (first == NULL)
	    first = last = r1;
	  else
	    {
	      last->next = r1;
	      last = r1;
	    }
	  r1 = r1->next;
	}
    }
  if (r1 != NULL)
    {
      if (first == NULL)
	first = r1;
      else
	last->next = r1;
    }
  else
    {
      lra_assert (r2 != NULL);
      if (first == NULL)
	first = r2;
      else
	last->next = r2;
    }
  return first;
}

/* Return TRUE if live ranges R1 and R2 intersect.  */
bool
lra_intersected_live_ranges_p (lra_live_range_t r1, lra_live_range_t r2)
{
  /* Remember the live ranges are always kept ordered.	*/
  while (r1 != NULL && r2 != NULL)
    {
      if (r1->start > r2->finish)
	r1 = r1->next;
      else if (r2->start > r1->finish)
	r2 = r2->next;
      else
	return true;
    }
  return false;
}

/* The function processing birth of hard register REGNO.  It updates
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   living hard regs, START_LIVING, and conflict hard regs for living
   pseudos.  Conflict hard regs for the pic pseudo is not updated if
   REGNO is REAL_PIC_OFFSET_TABLE_REGNUM and CHECK_PIC_PSEUDO_P is
   true.  */
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static void
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make_hard_regno_born (int regno, bool check_pic_pseudo_p ATTRIBUTE_UNUSED)
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{
  unsigned int i;

  lra_assert (regno < FIRST_PSEUDO_REGISTER);
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  if (TEST_HARD_REG_BIT (hard_regs_live, regno))
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    return;
  SET_HARD_REG_BIT (hard_regs_live, regno);
  sparseset_set_bit (start_living, regno);
  EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i)
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#ifdef REAL_PIC_OFFSET_TABLE_REGNUM
    if (! check_pic_pseudo_p
	|| regno != REAL_PIC_OFFSET_TABLE_REGNUM
	|| pic_offset_table_rtx == NULL
	|| i != REGNO (pic_offset_table_rtx))
#endif
      SET_HARD_REG_BIT (lra_reg_info[i].conflict_hard_regs, regno);
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}

/* Process the death of hard register REGNO.  This updates
   hard_regs_live and START_DYING.  */
static void
make_hard_regno_dead (int regno)
{
  lra_assert (regno < FIRST_PSEUDO_REGISTER);
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  if (! TEST_HARD_REG_BIT (hard_regs_live, regno))
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    return;
  sparseset_set_bit (start_dying, regno);
  CLEAR_HARD_REG_BIT (hard_regs_live, regno);
}

/* Mark pseudo REGNO as living at program point POINT, update conflicting
   hard registers of the pseudo and START_LIVING, and start a new live
   range for the pseudo corresponding to REGNO if it is necessary.  */
static void
mark_pseudo_live (int regno, int point)
{
  lra_live_range_t p;

  lra_assert (regno >= FIRST_PSEUDO_REGISTER);
  lra_assert (! sparseset_bit_p (pseudos_live, regno));
  sparseset_set_bit (pseudos_live, regno);
  IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs, hard_regs_live);

  if ((complete_info_p || lra_get_regno_hard_regno (regno) < 0)
      && ((p = lra_reg_info[regno].live_ranges) == NULL
	  || (p->finish != point && p->finish + 1 != point)))
     lra_reg_info[regno].live_ranges
       = create_live_range (regno, point, -1, p);
  sparseset_set_bit (start_living, regno);
}

/* Mark pseudo REGNO as not living at program point POINT and update
   START_DYING.
   This finishes the current live range for the pseudo corresponding
   to REGNO.  */
static void
mark_pseudo_dead (int regno, int point)
{
  lra_live_range_t p;

  lra_assert (regno >= FIRST_PSEUDO_REGISTER);
  lra_assert (sparseset_bit_p (pseudos_live, regno));
  sparseset_clear_bit (pseudos_live, regno);
  sparseset_set_bit (start_dying, regno);
  if (complete_info_p || lra_get_regno_hard_regno (regno) < 0)
    {
      p = lra_reg_info[regno].live_ranges;
      lra_assert (p != NULL);
      p->finish = point;
    }
}

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/* The corresponding bitmaps of BB currently being processed.  */
static bitmap bb_killed_pseudos, bb_gen_pseudos;

/* Mark register REGNO (pseudo or hard register) in MODE as live at
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   program point POINT.  Update BB_GEN_PSEUDOS.
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   Return TRUE if the liveness tracking sets were modified, or FALSE
   if nothing changed.  */
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static bool
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mark_regno_live (int regno, machine_mode mode, int point)
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{
  int last;
  bool changed = false;

  if (regno < FIRST_PSEUDO_REGISTER)
    {
      for (last = regno + hard_regno_nregs[regno][mode];
	   regno < last;
	   regno++)
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	make_hard_regno_born (regno, false);
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    }
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  else
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    {
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      if (! sparseset_bit_p (pseudos_live, regno))
	{
	  mark_pseudo_live (regno, point);
	  changed = true;
	}
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      bitmap_set_bit (bb_gen_pseudos, regno);
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    }
  return changed;
}


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/* Mark register REGNO in MODE as dead at program point POINT.  Update
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   BB_GEN_PSEUDOS and BB_KILLED_PSEUDOS.  Return TRUE if the liveness
   tracking sets were modified, or FALSE if nothing changed.  */
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static bool
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mark_regno_dead (int regno, machine_mode mode, int point)
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{
  int last;
  bool changed = false;

  if (regno < FIRST_PSEUDO_REGISTER)
    {
      for (last = regno + hard_regno_nregs[regno][mode];
	   regno < last;
	   regno++)
	make_hard_regno_dead (regno);
    }
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  else
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    {
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      if (sparseset_bit_p (pseudos_live, regno))
	{
	  mark_pseudo_dead (regno, point);
	  changed = true;
	}
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      bitmap_clear_bit (bb_gen_pseudos, regno);
      bitmap_set_bit (bb_killed_pseudos, regno);
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    }
  return changed;
}

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/* This page contains code for making global live analysis of pseudos.
   The code works only when pseudo live info is changed on a BB
   border.  That might be a consequence of some global transformations
   in LRA, e.g. PIC pseudo reuse or rematerialization.  */

/* Structure describing local BB data used for pseudo
   live-analysis.  */
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struct bb_data_pseudos
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{
  /* Basic block about which the below data are.  */
  basic_block bb;
  bitmap_head killed_pseudos; /* pseudos killed in the BB.  */
  bitmap_head gen_pseudos; /* pseudos generated in the BB.  */
};

/* Array for all BB data.  Indexed by the corresponding BB index.  */
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typedef struct bb_data_pseudos *bb_data_t;
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/* All basic block data are referred through the following array.  */
static bb_data_t bb_data;

/* Two small functions for access to the bb data.  */
static inline bb_data_t
get_bb_data (basic_block bb)
{
  return &bb_data[(bb)->index];
}

static inline bb_data_t
get_bb_data_by_index (int index)
{
  return &bb_data[index];
}

/* Bitmap with all hard regs.  */
static bitmap_head all_hard_regs_bitmap;

/* The transfer function used by the DF equation solver to propagate
   live info through block with BB_INDEX according to the following
   equation:

     bb.livein = (bb.liveout - bb.kill) OR bb.gen
*/
static bool
live_trans_fun (int bb_index)
{
  basic_block bb = get_bb_data_by_index (bb_index)->bb;
  bitmap bb_liveout = df_get_live_out (bb);
  bitmap bb_livein = df_get_live_in (bb);
  bb_data_t bb_info = get_bb_data (bb);

  bitmap_and_compl (&temp_bitmap, bb_liveout, &all_hard_regs_bitmap);
  return bitmap_ior_and_compl (bb_livein, &bb_info->gen_pseudos,
			       &temp_bitmap, &bb_info->killed_pseudos);
}

/* The confluence function used by the DF equation solver to set up
   live info for a block BB without predecessor.  */
static void
live_con_fun_0 (basic_block bb)
{
  bitmap_and_into (df_get_live_out (bb), &all_hard_regs_bitmap);
}

/* The confluence function used by the DF equation solver to propagate
   live info from successor to predecessor on edge E according to the
   following equation:

      bb.liveout = 0 for entry block | OR (livein of successors)
 */
static bool
live_con_fun_n (edge e)
{
  basic_block bb = e->src;
  basic_block dest = e->dest;
  bitmap bb_liveout = df_get_live_out (bb);
  bitmap dest_livein = df_get_live_in (dest);
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  return bitmap_ior_and_compl_into (bb_liveout,
				    dest_livein, &all_hard_regs_bitmap);
}

/* Indexes of all function blocks.  */
static bitmap_head all_blocks;

/* Allocate and initialize data needed for global pseudo live
   analysis.  */
static void
initiate_live_solver (void)
{
  bitmap_initialize (&all_hard_regs_bitmap, &reg_obstack);
  bitmap_set_range (&all_hard_regs_bitmap, 0, FIRST_PSEUDO_REGISTER);
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  bb_data = XNEWVEC (struct bb_data_pseudos, last_basic_block_for_fn (cfun));
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  bitmap_initialize (&all_blocks, &reg_obstack);

  basic_block bb;
  FOR_ALL_BB_FN (bb, cfun)
    {
      bb_data_t bb_info = get_bb_data (bb);
      bb_info->bb = bb;
      bitmap_initialize (&bb_info->killed_pseudos, &reg_obstack);
      bitmap_initialize (&bb_info->gen_pseudos, &reg_obstack);
      bitmap_set_bit (&all_blocks, bb->index);
    }
}

/* Free all data needed for global pseudo live analysis.  */
static void
finish_live_solver (void)
{
  basic_block bb;

  bitmap_clear (&all_blocks);
  FOR_ALL_BB_FN (bb, cfun)
    {
      bb_data_t bb_info = get_bb_data (bb);
      bitmap_clear (&bb_info->killed_pseudos);
      bitmap_clear (&bb_info->gen_pseudos);
    }
  free (bb_data);
  bitmap_clear (&all_hard_regs_bitmap);
}



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/* Insn currently scanned.  */
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static rtx_insn *curr_insn;
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/* The insn data.  */
static lra_insn_recog_data_t curr_id;
/* The insn static data.  */
static struct lra_static_insn_data *curr_static_id;

/* Vec containing execution frequencies of program points.  */
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static vec<int> point_freq_vec;
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/* The start of the above vector elements.  */
int *lra_point_freq;

/* Increment the current program point POINT to the next point which has
   execution frequency FREQ.  */
static void
next_program_point (int &point, int freq)
{
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  point_freq_vec.safe_push (freq);
  lra_point_freq = point_freq_vec.address ();
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  point++;
}

/* Update the preference of HARD_REGNO for pseudo REGNO by PROFIT.  */
void
lra_setup_reload_pseudo_preferenced_hard_reg (int regno,
					      int hard_regno, int profit)
{
  lra_assert (regno >= lra_constraint_new_regno_start);
  if (lra_reg_info[regno].preferred_hard_regno1 == hard_regno)
    lra_reg_info[regno].preferred_hard_regno_profit1 += profit;
  else if (lra_reg_info[regno].preferred_hard_regno2 == hard_regno)
    lra_reg_info[regno].preferred_hard_regno_profit2 += profit;
  else if (lra_reg_info[regno].preferred_hard_regno1 < 0)
    {
      lra_reg_info[regno].preferred_hard_regno1 = hard_regno;
      lra_reg_info[regno].preferred_hard_regno_profit1 = profit;
    }
  else if (lra_reg_info[regno].preferred_hard_regno2 < 0
	   || profit > lra_reg_info[regno].preferred_hard_regno_profit2)
    {
      lra_reg_info[regno].preferred_hard_regno2 = hard_regno;
      lra_reg_info[regno].preferred_hard_regno_profit2 = profit;
    }
  else
    return;
  /* Keep the 1st hard regno as more profitable.  */
  if (lra_reg_info[regno].preferred_hard_regno1 >= 0
      && lra_reg_info[regno].preferred_hard_regno2 >= 0
      && (lra_reg_info[regno].preferred_hard_regno_profit2
	  > lra_reg_info[regno].preferred_hard_regno_profit1))
    {
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      std::swap (lra_reg_info[regno].preferred_hard_regno1,
		 lra_reg_info[regno].preferred_hard_regno2);
      std::swap (lra_reg_info[regno].preferred_hard_regno_profit1,
		 lra_reg_info[regno].preferred_hard_regno_profit2);
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    }
  if (lra_dump_file != NULL)
    {
      if ((hard_regno = lra_reg_info[regno].preferred_hard_regno1) >= 0)
	fprintf (lra_dump_file,
		 "	Hard reg %d is preferable by r%d with profit %d\n",
		 hard_regno, regno,
		 lra_reg_info[regno].preferred_hard_regno_profit1);
      if ((hard_regno = lra_reg_info[regno].preferred_hard_regno2) >= 0)
	fprintf (lra_dump_file,
		 "	Hard reg %d is preferable by r%d with profit %d\n",
		 hard_regno, regno,
		 lra_reg_info[regno].preferred_hard_regno_profit2);
    }
}

/* Check that REGNO living through calls and setjumps, set up conflict
   regs, and clear corresponding bits in PSEUDOS_LIVE_THROUGH_CALLS and
   PSEUDOS_LIVE_THROUGH_SETJUMPS.  */
static inline void
check_pseudos_live_through_calls (int regno)
{
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  int hr;

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  if (! sparseset_bit_p (pseudos_live_through_calls, regno))
    return;
  sparseset_clear_bit (pseudos_live_through_calls, regno);
  IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs,
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		    call_used_reg_set);
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  for (hr = 0; hr < FIRST_PSEUDO_REGISTER; hr++)
    if (HARD_REGNO_CALL_PART_CLOBBERED (hr, PSEUDO_REGNO_MODE (regno)))
      SET_HARD_REG_BIT (lra_reg_info[regno].conflict_hard_regs, hr);
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  lra_reg_info[regno].call_p = true;
  if (! sparseset_bit_p (pseudos_live_through_setjumps, regno))
    return;
  sparseset_clear_bit (pseudos_live_through_setjumps, regno);
  /* Don't allocate pseudos that cross setjmps or any call, if this
     function receives a nonlocal goto.	 */
  SET_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs);
}

/* Process insns of the basic block BB to update pseudo live ranges,
   pseudo hard register conflicts, and insn notes.  We do it on
   backward scan of BB insns.  CURR_POINT is the program point where
   BB ends.  The function updates this counter and returns in
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   CURR_POINT the program point where BB starts.  The function also
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   does local live info updates and can delete the dead insns if
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   DEAD_INSN_P.  It returns true if pseudo live info was
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   changed at the BB start.  */
static bool
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process_bb_lives (basic_block bb, int &curr_point, bool dead_insn_p)
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{
  int i, regno, freq;
  unsigned int j;
  bitmap_iterator bi;
  bitmap reg_live_out;
  unsigned int px;
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  rtx_insn *next;
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  rtx link, *link_loc;
  bool need_curr_point_incr;

  reg_live_out = df_get_live_out (bb);
  sparseset_clear (pseudos_live);
  sparseset_clear (pseudos_live_through_calls);
  sparseset_clear (pseudos_live_through_setjumps);
  REG_SET_TO_HARD_REG_SET (hard_regs_live, reg_live_out);
  AND_COMPL_HARD_REG_SET (hard_regs_live, eliminable_regset);
  EXECUTE_IF_SET_IN_BITMAP (reg_live_out, FIRST_PSEUDO_REGISTER, j, bi)
    mark_pseudo_live (j, curr_point);

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  bb_gen_pseudos = &get_bb_data (bb)->gen_pseudos;
  bb_killed_pseudos = &get_bb_data (bb)->killed_pseudos;
  bitmap_clear (bb_gen_pseudos);
  bitmap_clear (bb_killed_pseudos);
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  freq = REG_FREQ_FROM_BB (bb);

  if (lra_dump_file != NULL)
    fprintf (lra_dump_file, "  BB %d\n", bb->index);

  /* Scan the code of this basic block, noting which pseudos and hard
     regs are born or die.

     Note that this loop treats uninitialized values as live until the
     beginning of the block.  For example, if an instruction uses
     (reg:DI foo), and only (subreg:SI (reg:DI foo) 0) is ever set,
     FOO will remain live until the beginning of the block.  Likewise
     if FOO is not set at all.	This is unnecessarily pessimistic, but
     it probably doesn't matter much in practice.  */
634
  FOR_BB_INSNS_REVERSE_SAFE (bb, curr_insn, next)
635 636 637 638 639 640 641 642 643 644 645 646 647 648 649
    {
      bool call_p;
      int dst_regno, src_regno;
      rtx set;
      struct lra_insn_reg *reg;

      if (!NONDEBUG_INSN_P (curr_insn))
	continue;

      curr_id = lra_get_insn_recog_data (curr_insn);
      curr_static_id = curr_id->insn_static_data;
      if (lra_dump_file != NULL)
	fprintf (lra_dump_file, "   Insn %u: point = %d\n",
		 INSN_UID (curr_insn), curr_point);

650 651
      set = single_set (curr_insn);

652
      if (dead_insn_p && set != NULL_RTX
653 654 655 656 657 658 659
	  && REG_P (SET_DEST (set)) && REGNO (SET_DEST (set)) >= FIRST_PSEUDO_REGISTER
	  && find_reg_note (curr_insn, REG_EH_REGION, NULL_RTX) == NULL_RTX
	  && ! may_trap_p (PATTERN (curr_insn))
	  /* Don't do premature remove of pic offset pseudo as we can
	     start to use it after some reload generation.  */
	  && (pic_offset_table_rtx == NULL_RTX
	      || pic_offset_table_rtx != SET_DEST (set)))
660
	{
661
	  bool remove_p = true;
662 663 664 665

	  for (reg = curr_id->regs; reg != NULL; reg = reg->next)
	    if (reg->type != OP_IN && sparseset_bit_p (pseudos_live, reg->regno))
	      {
666
		remove_p = false;
667 668 669 670 671
		break;
	      }
	  for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
	    if (reg->type != OP_IN)
	      {
672
		remove_p = false;
673 674
		break;
	      }
675
	  if (remove_p && ! volatile_refs_p (PATTERN (curr_insn)))
676 677 678 679 680 681 682 683 684 685 686 687
	    {
	      dst_regno = REGNO (SET_DEST (set));
	      if (lra_dump_file != NULL)
		fprintf (lra_dump_file, "   Deleting dead insn %u\n",
			 INSN_UID (curr_insn));
	      lra_set_insn_deleted (curr_insn);
	      if (lra_reg_info[dst_regno].nrefs == 0)
		{
		  /* There might be some debug insns with the pseudo.  */
		  unsigned int uid;
		  rtx_insn *insn;

688 689
		  bitmap_copy (&temp_bitmap, &lra_reg_info[dst_regno].insn_bitmap);
		  EXECUTE_IF_SET_IN_BITMAP (&temp_bitmap, 0, uid, bi)
690 691 692
		    {
		      insn = lra_insn_recog_data[uid]->insn;
		      lra_substitute_pseudo_within_insn (insn, dst_regno,
693
							 SET_SRC (set), true);
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		      lra_update_insn_regno_info (insn);
		    }
		}
	      continue;
	    }
	}

701 702 703 704 705 706 707 708 709 710
      /* Update max ref width and hard reg usage.  */
      for (reg = curr_id->regs; reg != NULL; reg = reg->next)
	if (reg->regno >= FIRST_PSEUDO_REGISTER
	    && (GET_MODE_SIZE (reg->biggest_mode)
		> GET_MODE_SIZE (lra_reg_info[reg->regno].biggest_mode)))
	  lra_reg_info[reg->regno].biggest_mode = reg->biggest_mode;
	else if (reg->regno < FIRST_PSEUDO_REGISTER)
	  lra_hard_reg_usage[reg->regno] += freq;

      call_p = CALL_P (curr_insn);
711 712 713 714
      src_regno = (set != NULL_RTX && REG_P (SET_SRC (set))
		   ? REGNO (SET_SRC (set)) : -1);
      dst_regno = (set != NULL_RTX && REG_P (SET_DEST (set))
		   ? REGNO (SET_DEST (set)) : -1);
715
      if (complete_info_p
716
	  && src_regno >= 0 && dst_regno >= 0
717 718 719
	  /* Check that source regno does not conflict with
	     destination regno to exclude most impossible
	     preferences.  */
720 721 722 723 724 725
	  && (((src_regno >= FIRST_PSEUDO_REGISTER
		&& (! sparseset_bit_p (pseudos_live, src_regno)
		    || (dst_regno >= FIRST_PSEUDO_REGISTER
			&& lra_reg_val_equal_p (src_regno,
						lra_reg_info[dst_regno].val,
						lra_reg_info[dst_regno].offset))))
726 727 728 729
	       || (src_regno < FIRST_PSEUDO_REGISTER
		   && ! TEST_HARD_REG_BIT (hard_regs_live, src_regno)))
	      /* It might be 'inheritance pseudo <- reload pseudo'.  */
	      || (src_regno >= lra_constraint_new_regno_start
730
		  && dst_regno >= lra_constraint_new_regno_start
731 732 733
		  /* Remember to skip special cases where src/dest regnos are
		     the same, e.g. insn SET pattern has matching constraints
		     like =r,0.  */
734
		  && src_regno != dst_regno)))
735 736 737 738 739
	{
	  int hard_regno = -1, regno = -1;

	  if (dst_regno >= lra_constraint_new_regno_start
	      && src_regno >= lra_constraint_new_regno_start)
740 741 742 743 744 745 746 747 748
	    {
	      /* It might be still an original (non-reload) insn with
		 one unused output and a constraint requiring to use
		 the same reg for input/output operands. In this case
		 dst_regno and src_regno have the same value, we don't
		 need a misleading copy for this case.  */
	      if (dst_regno != src_regno)
		lra_create_copy (dst_regno, src_regno, freq);
	    }
749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779
	  else if (dst_regno >= lra_constraint_new_regno_start)
	    {
	      if ((hard_regno = src_regno) >= FIRST_PSEUDO_REGISTER)
		hard_regno = reg_renumber[src_regno];
	      regno = dst_regno;
	    }
	  else if (src_regno >= lra_constraint_new_regno_start)
	    {
	      if ((hard_regno = dst_regno) >= FIRST_PSEUDO_REGISTER)
		hard_regno = reg_renumber[dst_regno];
	      regno = src_regno;
	    }
	  if (regno >= 0 && hard_regno >= 0)
	    lra_setup_reload_pseudo_preferenced_hard_reg
	      (regno, hard_regno, freq);
	}

      sparseset_clear (start_living);

      /* Try to avoid unnecessary program point increments, this saves
	 a lot of time in remove_some_program_points_and_update_live_ranges.
	 We only need an increment if something becomes live or dies at this
	 program point.  */
      need_curr_point_incr = false;

      /* Mark each defined value as live.  We need to do this for
	 unused values because they still conflict with quantities
	 that are live at the time of the definition.  */
      for (reg = curr_id->regs; reg != NULL; reg = reg->next)
	if (reg->type != OP_IN)
	  {
780 781
	    need_curr_point_incr
	      |= mark_regno_live (reg->regno, reg->biggest_mode,
782
				  curr_point);
783 784 785 786 787
	    check_pseudos_live_through_calls (reg->regno);
	  }

      for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
	if (reg->type != OP_IN)
788
	  make_hard_regno_born (reg->regno, false);
789

790 791 792 793 794 795
      if (curr_id->arg_hard_regs != NULL)
	for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
	  if (regno >= FIRST_PSEUDO_REGISTER)
	    /* It is a clobber.  */
	    make_hard_regno_born (regno - FIRST_PSEUDO_REGISTER, false);

796 797 798 799 800 801 802
      sparseset_copy (unused_set, start_living);

      sparseset_clear (start_dying);

      /* See which defined values die here.  */
      for (reg = curr_id->regs; reg != NULL; reg = reg->next)
	if (reg->type == OP_OUT && ! reg->early_clobber && ! reg->subreg_p)
803 804
	  need_curr_point_incr
	    |= mark_regno_dead (reg->regno, reg->biggest_mode,
805
				curr_point);
806 807 808 809 810

      for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
	if (reg->type == OP_OUT && ! reg->early_clobber && ! reg->subreg_p)
	  make_hard_regno_dead (reg->regno);

811 812 813 814 815 816
      if (curr_id->arg_hard_regs != NULL)
	for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
	  if (regno >= FIRST_PSEUDO_REGISTER)
	    /* It is a clobber.  */
	    make_hard_regno_dead (regno - FIRST_PSEUDO_REGISTER);

817 818
      if (call_p)
	{
Tom de Vries committed
819
	  if (flag_ipa_ra)
820 821 822 823 824 825 826 827 828 829
	    {
	      HARD_REG_SET this_call_used_reg_set;
	      get_call_reg_set_usage (curr_insn, &this_call_used_reg_set,
				      call_used_reg_set);

	      EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, j)
		IOR_HARD_REG_SET (lra_reg_info[j].actual_call_used_reg_set,
				  this_call_used_reg_set);
	    }

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	  sparseset_ior (pseudos_live_through_calls,
			 pseudos_live_through_calls, pseudos_live);
	  if (cfun->has_nonlocal_label
	      || find_reg_note (curr_insn, REG_SETJMP,
				NULL_RTX) != NULL_RTX)
	    sparseset_ior (pseudos_live_through_setjumps,
			   pseudos_live_through_setjumps, pseudos_live);
	}

      /* Increment the current program point if we must.  */
      if (need_curr_point_incr)
	next_program_point (curr_point, freq);

      sparseset_clear (start_living);

      need_curr_point_incr = false;

      /* Mark each used value as live.	*/
      for (reg = curr_id->regs; reg != NULL; reg = reg->next)
	if (reg->type == OP_IN)
	  {
851 852
	    need_curr_point_incr
	      |= mark_regno_live (reg->regno, reg->biggest_mode,
853
				  curr_point);
854 855 856 857 858
	    check_pseudos_live_through_calls (reg->regno);
	  }

      for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
	if (reg->type == OP_IN)
859
	  make_hard_regno_born (reg->regno, false);
860 861

      if (curr_id->arg_hard_regs != NULL)
862 863
	/* Make argument hard registers live.  Don't create conflict
	   of used REAL_PIC_OFFSET_TABLE_REGNUM and the pic pseudo.  */
864
	for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
865 866
	  if (regno < FIRST_PSEUDO_REGISTER)
	    make_hard_regno_born (regno, true);
867 868 869 870 871 872

      sparseset_and_compl (dead_set, start_living, start_dying);

      /* Mark early clobber outputs dead.  */
      for (reg = curr_id->regs; reg != NULL; reg = reg->next)
	if (reg->type == OP_OUT && reg->early_clobber && ! reg->subreg_p)
873 874
	  need_curr_point_incr
	    |= mark_regno_dead (reg->regno, reg->biggest_mode,
875
				curr_point);
876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920

      for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
	if (reg->type == OP_OUT && reg->early_clobber && ! reg->subreg_p)
	  make_hard_regno_dead (reg->regno);

      if (need_curr_point_incr)
	next_program_point (curr_point, freq);

      /* Update notes.	*/
      for (link_loc = &REG_NOTES (curr_insn); (link = *link_loc) != NULL_RTX;)
	{
	  if (REG_NOTE_KIND (link) != REG_DEAD
	      && REG_NOTE_KIND (link) != REG_UNUSED)
	    ;
	  else if (REG_P (XEXP (link, 0)))
	    {
	      regno = REGNO (XEXP (link, 0));
	      if ((REG_NOTE_KIND (link) == REG_DEAD
		   && ! sparseset_bit_p (dead_set, regno))
		  || (REG_NOTE_KIND (link) == REG_UNUSED
		      && ! sparseset_bit_p (unused_set, regno)))
		{
		  *link_loc = XEXP (link, 1);
		  continue;
		}
	      if (REG_NOTE_KIND (link) == REG_DEAD)
		sparseset_clear_bit (dead_set, regno);
	      else if (REG_NOTE_KIND (link) == REG_UNUSED)
		sparseset_clear_bit (unused_set, regno);
	    }
	  link_loc = &XEXP (link, 1);
	}
      EXECUTE_IF_SET_IN_SPARSESET (dead_set, j)
	add_reg_note (curr_insn, REG_DEAD, regno_reg_rtx[j]);
      EXECUTE_IF_SET_IN_SPARSESET (unused_set, j)
	add_reg_note (curr_insn, REG_UNUSED, regno_reg_rtx[j]);
    }

  if (bb_has_eh_pred (bb))
    for (j = 0; ; ++j)
      {
	unsigned int regno = EH_RETURN_DATA_REGNO (j);

	if (regno == INVALID_REGNUM)
	  break;
921
	make_hard_regno_born (regno, false);
922 923 924 925 926 927 928 929 930 931 932 933 934
      }

  /* Pseudos can't go in stack regs at the start of a basic block that
     is reached by an abnormal edge. Likewise for call clobbered regs,
     because caller-save, fixup_abnormal_edges and possibly the table
     driven EH machinery are not quite ready to handle such pseudos
     live across such edges.  */
  if (bb_has_abnormal_pred (bb))
    {
#ifdef STACK_REGS
      EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, px)
	lra_reg_info[px].no_stack_p = true;
      for (px = FIRST_STACK_REG; px <= LAST_STACK_REG; px++)
935
	make_hard_regno_born (px, false);
936 937 938 939
#endif
      /* No need to record conflicts for call clobbered regs if we
	 have nonlocal labels around, as we don't ever try to
	 allocate such regs in this case.  */
940 941
      if (!cfun->has_nonlocal_label
	  && has_abnormal_call_or_eh_pred_edge_p (bb))
942
	for (px = 0; px < FIRST_PSEUDO_REGISTER; px++)
943 944 945 946 947 948 949 950 951 952 953 954
	  if (call_used_regs[px]
#ifdef REAL_PIC_OFFSET_TABLE_REGNUM
	      /* We should create a conflict of PIC pseudo with PIC
		 hard reg as PIC hard reg can have a wrong value after
		 jump described by the abnormal edge.  In this case we
		 can not allocate PIC hard reg to PIC pseudo as PIC
		 pseudo will also have a wrong value.  */
	      || (px == REAL_PIC_OFFSET_TABLE_REGNUM
		  && pic_offset_table_rtx != NULL_RTX
		  && REGNO (pic_offset_table_rtx) >= FIRST_PSEUDO_REGISTER)
#endif
	      )
955
	    make_hard_regno_born (px, false);
956 957
    }

958
  bool live_change_p = false;
959 960 961 962
  /* Check if bb border live info was changed.  */
  unsigned int live_pseudos_num = 0;
  EXECUTE_IF_SET_IN_BITMAP (df_get_live_in (bb),
			    FIRST_PSEUDO_REGISTER, j, bi)
963
    {
964 965
      live_pseudos_num++;
      if (! sparseset_bit_p (pseudos_live, j))
966
	{
967 968 969 970
	  live_change_p = true;
	  if (lra_dump_file != NULL)
	    fprintf (lra_dump_file,
		     "  r%d is removed as live at bb%d start\n", j, bb->index);
971
	  break;
972 973
	}
    }
974 975 976 977 978 979 980 981 982 983
  if (! live_change_p
      && sparseset_cardinality (pseudos_live) != live_pseudos_num)
    {
      live_change_p = true;
      if (lra_dump_file != NULL)
	EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, j)
	  if (! bitmap_bit_p (df_get_live_in (bb), j))
	    fprintf (lra_dump_file,
		     "  r%d is added to live at bb%d start\n", j, bb->index);
    }
984 985 986 987 988 989 990 991 992 993 994 995 996 997 998
  /* See if we'll need an increment at the end of this basic block.
     An increment is needed if the PSEUDOS_LIVE set is not empty,
     to make sure the finish points are set up correctly.  */
  need_curr_point_incr = (sparseset_cardinality (pseudos_live) > 0);

  EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i)
    mark_pseudo_dead (i, curr_point);

  EXECUTE_IF_SET_IN_BITMAP (df_get_live_in (bb), FIRST_PSEUDO_REGISTER, j, bi)
    {
      if (sparseset_cardinality (pseudos_live_through_calls) == 0)
	break;
      if (sparseset_bit_p (pseudos_live_through_calls, j))
	check_pseudos_live_through_calls (j);
    }
999

1000 1001
  if (need_curr_point_incr)
    next_program_point (curr_point, freq);
1002 1003

  return live_change_p;
1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022
}

/* Compress pseudo live ranges by removing program points where
   nothing happens.  Complexity of many algorithms in LRA is linear
   function of program points number.  To speed up the code we try to
   minimize the number of the program points here.  */
static void
remove_some_program_points_and_update_live_ranges (void)
{
  unsigned i;
  int n, max_regno;
  int *map;
  lra_live_range_t r, prev_r, next_r;
  sbitmap born_or_dead, born, dead;
  sbitmap_iterator sbi;
  bool born_p, dead_p, prev_born_p, prev_dead_p;

  born = sbitmap_alloc (lra_live_max_point);
  dead = sbitmap_alloc (lra_live_max_point);
1023 1024
  bitmap_clear (born);
  bitmap_clear (dead);
1025 1026 1027 1028 1029 1030
  max_regno = max_reg_num ();
  for (i = FIRST_PSEUDO_REGISTER; i < (unsigned) max_regno; i++)
    {
      for (r = lra_reg_info[i].live_ranges; r != NULL; r = r->next)
	{
	  lra_assert (r->start <= r->finish);
1031 1032
	  bitmap_set_bit (born, r->start);
	  bitmap_set_bit (dead, r->finish);
1033 1034 1035
	}
    }
  born_or_dead = sbitmap_alloc (lra_live_max_point);
1036
  bitmap_ior (born_or_dead, born, dead);
1037 1038 1039
  map = XCNEWVEC (int, lra_live_max_point);
  n = -1;
  prev_born_p = prev_dead_p = false;
1040
  EXECUTE_IF_SET_IN_BITMAP (born_or_dead, 0, i, sbi)
1041
    {
1042 1043
      born_p = bitmap_bit_p (born, i);
      dead_p = bitmap_bit_p (dead, i);
1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083
      if ((prev_born_p && ! prev_dead_p && born_p && ! dead_p)
	  || (prev_dead_p && ! prev_born_p && dead_p && ! born_p))
	{
	  map[i] = n;
	  lra_point_freq[n] = MAX (lra_point_freq[n], lra_point_freq[i]);
	}
      else
	{
	  map[i] = ++n;
	  lra_point_freq[n] = lra_point_freq[i];
	}
      prev_born_p = born_p;
      prev_dead_p = dead_p;
    }
  sbitmap_free (born_or_dead);
  sbitmap_free (born);
  sbitmap_free (dead);
  n++;
  if (lra_dump_file != NULL)
    fprintf (lra_dump_file, "Compressing live ranges: from %d to %d - %d%%\n",
	     lra_live_max_point, n, 100 * n / lra_live_max_point);
  if (n < lra_live_max_point)
    {
      lra_live_max_point = n;
      for (i = FIRST_PSEUDO_REGISTER; i < (unsigned) max_regno; i++)
	{
	  for (prev_r = NULL, r = lra_reg_info[i].live_ranges;
	       r != NULL;
	       r = next_r)
	    {
	      next_r = r->next;
	      r->start = map[r->start];
	      r->finish = map[r->finish];
	      if (prev_r == NULL || prev_r->start > r->finish + 1)
		{
		  prev_r = r;
		  continue;
		}
	      prev_r->start = r->start;
	      prev_r->next = next_r;
1084
	      lra_live_range_pool.remove (r);
1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
	    }
	}
    }
  free (map);
}

/* Print live ranges R to file F.  */
void
lra_print_live_range_list (FILE *f, lra_live_range_t r)
{
  for (; r != NULL; r = r->next)
    fprintf (f, " [%d..%d]", r->start, r->finish);
  fprintf (f, "\n");
}

1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114
DEBUG_FUNCTION void
debug (lra_live_range &ref)
{
  lra_print_live_range_list (stderr, &ref);
}

DEBUG_FUNCTION void
debug (lra_live_range *ptr)
{
  if (ptr)
    debug (*ptr);
  else
    fprintf (stderr, "<nil>\n");
}

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/* Print live ranges R to stderr.  */
void
lra_debug_live_range_list (lra_live_range_t r)
{
  lra_print_live_range_list (stderr, r);
}

/* Print live ranges of pseudo REGNO to file F.	 */
static void
print_pseudo_live_ranges (FILE *f, int regno)
{
  if (lra_reg_info[regno].live_ranges == NULL)
    return;
  fprintf (f, " r%d:", regno);
  lra_print_live_range_list (f, lra_reg_info[regno].live_ranges);
}

/* Print live ranges of pseudo REGNO to stderr.	 */
void
lra_debug_pseudo_live_ranges (int regno)
{
  print_pseudo_live_ranges (stderr, regno);
}

/* Print live ranges of all pseudos to file F.	*/
static void
print_live_ranges (FILE *f)
{
  int i, max_regno;

  max_regno = max_reg_num ();
  for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
    print_pseudo_live_ranges (f, i);
}

/* Print live ranges of all pseudos to stderr.	*/
void
lra_debug_live_ranges (void)
{
  print_live_ranges (stderr);
}

/* Compress pseudo live ranges.	 */
static void
compress_live_ranges (void)
{
  remove_some_program_points_and_update_live_ranges ();
  if (lra_dump_file != NULL)
    {
      fprintf (lra_dump_file, "Ranges after the compression:\n");
      print_live_ranges (lra_dump_file);
    }
}

1169 1170


1171 1172 1173
/* The number of the current live range pass.  */
int lra_live_range_iter;

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/* The function creates live ranges only for memory pseudos (or for
   all ones if ALL_P), set up CONFLICT_HARD_REGS for the pseudos.  It
   also does dead insn elimination if DEAD_INSN_P and global live
   analysis only for pseudos and only if the pseudo live info was
   changed on a BB border.  Return TRUE if the live info was
   changed.  */
static bool
lra_create_live_ranges_1 (bool all_p, bool dead_insn_p)
1182 1183 1184 1185
{
  basic_block bb;
  int i, hard_regno, max_regno = max_reg_num ();
  int curr_point;
1186
  bool bb_live_change_p, have_referenced_pseudos = false;
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  timevar_push (TV_LRA_CREATE_LIVE_RANGES);

  complete_info_p = all_p;
  if (lra_dump_file != NULL)
    fprintf (lra_dump_file,
	     "\n********** Pseudo live ranges #%d: **********\n\n",
	     ++lra_live_range_iter);
  memset (lra_hard_reg_usage, 0, sizeof (lra_hard_reg_usage));
  for (i = 0; i < max_regno; i++)
    {
      lra_reg_info[i].live_ranges = NULL;
      CLEAR_HARD_REG_SET (lra_reg_info[i].conflict_hard_regs);
      lra_reg_info[i].preferred_hard_regno1 = -1;
      lra_reg_info[i].preferred_hard_regno2 = -1;
      lra_reg_info[i].preferred_hard_regno_profit1 = 0;
      lra_reg_info[i].preferred_hard_regno_profit2 = 0;
#ifdef STACK_REGS
      lra_reg_info[i].no_stack_p = false;
#endif
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      /* The biggest mode is already set but its value might be to
	 conservative because of recent transformation.  Here in this
	 file we recalculate it again as it costs practically
	 nothing.  */
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      if (regno_reg_rtx[i] != NULL_RTX)
	lra_reg_info[i].biggest_mode = GET_MODE (regno_reg_rtx[i]);
      else
	lra_reg_info[i].biggest_mode = VOIDmode;
      lra_reg_info[i].call_p = false;
      if (i >= FIRST_PSEUDO_REGISTER
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	  && lra_reg_info[i].nrefs != 0)
	{
	  if ((hard_regno = reg_renumber[i]) >= 0)
	    lra_hard_reg_usage[hard_regno] += lra_reg_info[i].freq;
	  have_referenced_pseudos = true;
	}
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    }
  lra_free_copies ();
1225

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  /* Under some circumstances, we can have functions without pseudo
     registers.  For such functions, lra_live_max_point will be 0,
     see e.g. PR55604, and there's nothing more to do for us here.  */
  if (! have_referenced_pseudos)
    {
      timevar_pop (TV_LRA_CREATE_LIVE_RANGES);
1232
      return false;
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    }

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  pseudos_live = sparseset_alloc (max_regno);
  pseudos_live_through_calls = sparseset_alloc (max_regno);
  pseudos_live_through_setjumps = sparseset_alloc (max_regno);
  start_living = sparseset_alloc (max_regno);
  start_dying = sparseset_alloc (max_regno);
  dead_set = sparseset_alloc (max_regno);
  unused_set = sparseset_alloc (max_regno);
  curr_point = 0;
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  unsigned new_length = get_max_uid () * 2;
  if (point_freq_vec.length () < new_length)
    point_freq_vec.safe_grow (new_length);
1246
  lra_point_freq = point_freq_vec.address ();
1247
  int *post_order_rev_cfg = XNEWVEC (int, last_basic_block_for_fn (cfun));
1248
  int n_blocks_inverted = inverted_post_order_compute (post_order_rev_cfg);
1249
  lra_assert (n_blocks_inverted == n_basic_blocks_for_fn (cfun));
1250
  bb_live_change_p = false;
1251 1252
  for (i = n_blocks_inverted - 1; i >= 0; --i)
    {
1253
      bb = BASIC_BLOCK_FOR_FN (cfun, post_order_rev_cfg[i]);
1254 1255
      if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun) || bb
	  == ENTRY_BLOCK_PTR_FOR_FN (cfun))
1256
	continue;
1257
      if (process_bb_lives (bb, curr_point, dead_insn_p))
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	bb_live_change_p = true;
    }
  if (bb_live_change_p)
    {
      /* We need to clear pseudo live info as some pseudos can
	 disappear, e.g. pseudos with used equivalences.  */
      FOR_EACH_BB_FN (bb, cfun)
	{
	  bitmap_clear_range (df_get_live_in (bb), FIRST_PSEUDO_REGISTER,
			      max_regno - FIRST_PSEUDO_REGISTER);
	  bitmap_clear_range (df_get_live_out (bb), FIRST_PSEUDO_REGISTER,
			      max_regno - FIRST_PSEUDO_REGISTER);
	}
      /* As we did not change CFG since LRA start we can use
	 DF-infrastructure solver to solve live data flow problem.  */
      df_simple_dataflow
	(DF_BACKWARD, NULL, live_con_fun_0, live_con_fun_n,
	 live_trans_fun, &all_blocks,
	 df_get_postorder (DF_BACKWARD), df_get_n_blocks (DF_BACKWARD));
      if (lra_dump_file != NULL)
	{
1279 1280
	  fprintf (lra_dump_file,
		   "Global pseudo live data have been updated:\n");
1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296
	  basic_block bb;
	  FOR_EACH_BB_FN (bb, cfun)
	    {
	      bb_data_t bb_info = get_bb_data (bb);
	      bitmap bb_livein = df_get_live_in (bb);
	      bitmap bb_liveout = df_get_live_out (bb);

	      fprintf (lra_dump_file, "\nBB %d:\n", bb->index);
	      lra_dump_bitmap_with_title ("  gen:",
					  &bb_info->gen_pseudos, bb->index);
	      lra_dump_bitmap_with_title ("  killed:",
					  &bb_info->killed_pseudos, bb->index);
	      lra_dump_bitmap_with_title ("  livein:", bb_livein, bb->index);
	      lra_dump_bitmap_with_title ("  liveout:", bb_liveout, bb->index);
	    }
	}
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    }
  free (post_order_rev_cfg);
  lra_live_max_point = curr_point;
  if (lra_dump_file != NULL)
    print_live_ranges (lra_dump_file);
  /* Clean up.	*/
  sparseset_free (unused_set);
  sparseset_free (dead_set);
  sparseset_free (start_dying);
  sparseset_free (start_living);
  sparseset_free (pseudos_live_through_calls);
  sparseset_free (pseudos_live_through_setjumps);
  sparseset_free (pseudos_live);
  compress_live_ranges ();
  timevar_pop (TV_LRA_CREATE_LIVE_RANGES);
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  return bb_live_change_p;
}

/* The main entry function creates live-ranges and other live info
   necessary for the assignment sub-pass.  It uses
   lra_creates_live_ranges_1 -- so read comments for the
   function.  */
void
lra_create_live_ranges (bool all_p, bool dead_insn_p)
{
  if (! lra_create_live_ranges_1 (all_p, dead_insn_p))
    return;
  if (lra_dump_file != NULL)
    fprintf (lra_dump_file, "Live info was changed -- recalculate it\n");
  /* Live info was changed on a bb border.  It means that some info,
1327 1328 1329 1330 1331 1332 1333 1334
     e.g. about conflict regs, calls crossed, and live ranges may be
     wrong.  We need this info for allocation.  So recalculate it
     again but without removing dead insns which can change live info
     again.  Repetitive live range calculations are expensive therefore
     we stop here as we already have correct info although some
     improvement in rare cases could be possible on this sub-pass if
     we do dead insn elimination again (still the improvement may
     happen later).  */
1335
  lra_clear_live_ranges ();
1336
  bool res = lra_create_live_ranges_1 (all_p, false);
1337
  lra_assert (! res);
1338 1339 1340 1341 1342 1343 1344 1345 1346 1347
}

/* Finish all live ranges.  */
void
lra_clear_live_ranges (void)
{
  int i;

  for (i = 0; i < max_reg_num (); i++)
    free_live_range_list (lra_reg_info[i].live_ranges);
1348
  point_freq_vec.release ();
1349 1350 1351 1352 1353 1354
}

/* Initialize live ranges data once per function.  */
void
lra_live_ranges_init (void)
{
1355
  bitmap_initialize (&temp_bitmap, &reg_obstack);
1356
  initiate_live_solver ();
1357 1358 1359 1360 1361 1362
}

/* Finish live ranges data once per function.  */
void
lra_live_ranges_finish (void)
{
1363
  finish_live_solver ();
1364
  bitmap_clear (&temp_bitmap);
1365
  lra_live_range_pool.release ();
1366
}