X-Git-Url: http://git.sourceforge.jp/view?a=blobdiff_plain;f=gcc%2Fdf-problems.c;h=25bbba61bb1d05b7f82bb99d0c014c98fa76e5bc;hb=653d0639db9f426c9cc72bdb620d2d06055af72e;hp=84dc42a13612928db7f1cc0349ee6dd62e0afd0b;hpb=8dc2823a2f3ba69e89bcb0189f9e2f95021f0cb6;p=pf3gnuchains%2Fgcc-fork.git

diff --git a/gcc/df-problems.c b/gcc/df-problems.c
index 84dc42a1361..25bbba61bb1 100644
--- a/gcc/df-problems.c
+++ b/gcc/df-problems.c
@@ -1,7 +1,7 @@
 /* Standard problems for dataflow support routines.
    Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
-   2008, 2009 Free Software Foundation, Inc.
-   Originally contributed by Michael P. Hayes 
+   2008, 2009, 2010 Free Software Foundation, Inc.
+   Originally contributed by Michael P. Hayes
              (m.hayes@elec.canterbury.ac.nz, mhayes@redhat.com)
    Major rewrite contributed by Danny Berlin (dberlin@dberlin.org)
              and Kenneth Zadeck (zadeck@naturalbridge.com).
@@ -47,7 +47,7 @@ along with GCC; see the file COPYING3.  If not see
 
 /* Note that turning REG_DEAD_DEBUGGING on will cause
    gcc.c-torture/unsorted/dump-noaddr.c to fail because it prints
-   addresses in the dumps.  */  
+   addresses in the dumps.  */
 #if 0
 #define REG_DEAD_DEBUGGING
 #endif
@@ -73,7 +73,7 @@ df_get_live_out (basic_block bb)
 
   if (df_live)
     return DF_LIVE_OUT (bb);
-  else 
+  else
     return DF_LR_OUT (bb);
 }
 
@@ -89,7 +89,7 @@ df_get_live_in (basic_block bb)
 
   if (df_live)
     return DF_LIVE_IN (bb);
-  else 
+  else
     return DF_LR_IN (bb);
 }
 
@@ -136,7 +136,7 @@ df_chain_dump (struct df_link *link, FILE *file)
 
 /* Print some basic block info as part of df_dump.  */
 
-void 
+void
 df_print_bb_index (basic_block bb, FILE *file)
 {
   edge e;
@@ -147,37 +147,16 @@ df_print_bb_index (basic_block bb, FILE *file)
     {
       basic_block pred = e->src;
       fprintf (file, "%d%s ", pred->index, e->flags & EDGE_EH ? "(EH)" : "");
-    } 
+    }
   fprintf (file, ")->[%d]->( ", bb->index);
   FOR_EACH_EDGE (e, ei, bb->succs)
     {
       basic_block succ = e->dest;
       fprintf (file, "%d%s ", succ->index, e->flags & EDGE_EH ? "(EH)" : "");
-    } 
+    }
   fprintf (file, ")\n");
 }
 
-
-
-/* Make sure that the seen_in_insn and seen_in_block sbitmaps are set
-   up correctly. */
-
-static void
-df_set_seen (void)
-{
-  seen_in_block = BITMAP_ALLOC (&df_bitmap_obstack);
-  seen_in_insn = BITMAP_ALLOC (&df_bitmap_obstack);
-}
-
-
-static void
-df_unset_seen (void)
-{
-  BITMAP_FREE (seen_in_block);
-  BITMAP_FREE (seen_in_insn);
-}
-
-
 
 /*----------------------------------------------------------------------------
    REACHING DEFINITIONS
@@ -189,12 +168,12 @@ df_unset_seen (void)
    ----------------------------------------------------------------------------*/
 
 /* This problem plays a large number of games for the sake of
-   efficiency.  
-   
+   efficiency.
+
    1) The order of the bits in the bitvectors.  After the scanning
    phase, all of the defs are sorted.  All of the defs for the reg 0
    are first, followed by all defs for reg 1 and so on.
-   
+
    2) There are two kill sets, one if the number of defs is less or
    equal to DF_SPARSE_THRESHOLD and another if the number of defs is
    greater.
@@ -216,8 +195,8 @@ df_unset_seen (void)
 struct df_rd_problem_data
 {
   /* The set of defs to regs invalidated by call.  */
-  bitmap sparse_invalidated_by_call;  
-  /* The set of defs to regs invalidate by call for rd.  */  
+  bitmap sparse_invalidated_by_call;
+  /* The set of defs to regs invalidate by call for rd.  */
   bitmap dense_invalidated_by_call;
   /* An obstack for the bitmaps we need for this problem.  */
   bitmap_obstack rd_bitmaps;
@@ -226,7 +205,7 @@ struct df_rd_problem_data
 /* Set basic block info.  */
 
 static void
-df_rd_set_bb_info (unsigned int index, 
+df_rd_set_bb_info (unsigned int index,
 		   struct df_rd_bb_info *bb_info)
 {
   gcc_assert (df_rd);
@@ -238,7 +217,7 @@ df_rd_set_bb_info (unsigned int index,
 /* Free basic block info.  */
 
 static void
-df_rd_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, 
+df_rd_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 		    void *vbb_info)
 {
   struct df_rd_bb_info *bb_info = (struct df_rd_bb_info *) vbb_info;
@@ -257,7 +236,7 @@ df_rd_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 /* Allocate or reset bitmaps for DF_RD blocks. The solution bits are
    not touched unless the block is new.  */
 
-static void 
+static void
 df_rd_alloc (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -265,7 +244,7 @@ df_rd_alloc (bitmap all_blocks)
   struct df_rd_problem_data *problem_data;
 
   if (!df_rd->block_pool)
-    df_rd->block_pool = create_alloc_pool ("df_rd_block pool", 
+    df_rd->block_pool = create_alloc_pool ("df_rd_block pool",
 					   sizeof (struct df_rd_bb_info), 50);
 
   if (df_rd->problem_data)
@@ -274,7 +253,7 @@ df_rd_alloc (bitmap all_blocks)
       bitmap_clear (problem_data->sparse_invalidated_by_call);
       bitmap_clear (problem_data->dense_invalidated_by_call);
     }
-  else 
+  else
     {
       problem_data = XNEW (struct df_rd_problem_data);
       df_rd->problem_data = problem_data;
@@ -296,13 +275,13 @@ df_rd_alloc (bitmap all_blocks)
     {
       struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
       if (bb_info)
-	{ 
+	{
 	  bitmap_clear (bb_info->kill);
 	  bitmap_clear (bb_info->sparse_kill);
 	  bitmap_clear (bb_info->gen);
 	}
       else
-	{ 
+	{
 	  bb_info = (struct df_rd_bb_info *) pool_alloc (df_rd->block_pool);
 	  df_rd_set_bb_info (bb_index, bb_info);
 	  bb_info->kill = BITMAP_ALLOC (&problem_data->rd_bitmaps);
@@ -331,8 +310,8 @@ df_rd_simulate_artificial_defs_at_top (basic_block bb, bitmap local_rd)
 	{
 	  unsigned int dregno = DF_REF_REGNO (def);
 	  if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
-	    bitmap_clear_range (local_rd, 
-				DF_DEFS_BEGIN (dregno), 
+	    bitmap_clear_range (local_rd,
+				DF_DEFS_BEGIN (dregno),
 				DF_DEFS_COUNT (dregno));
 	  bitmap_set_bit (local_rd, DF_REF_ID (def));
 	}
@@ -357,10 +336,10 @@ df_rd_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx insn,
           || (dregno >= FIRST_PSEUDO_REGISTER))
         {
           if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
-	    bitmap_clear_range (local_rd, 
-				DF_DEFS_BEGIN (dregno), 
+	    bitmap_clear_range (local_rd,
+				DF_DEFS_BEGIN (dregno),
 				DF_DEFS_COUNT (dregno));
-	  if (!(DF_REF_FLAGS (def) 
+	  if (!(DF_REF_FLAGS (def)
 		& (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)))
 	    bitmap_set_bit (local_rd, DF_REF_ID (def));
 	}
@@ -373,7 +352,7 @@ df_rd_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx insn,
    of kill sets.   */
 
 static void
-df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info, 
+df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info,
 				    df_ref *def_rec,
 				    int top_flag)
 {
@@ -385,12 +364,12 @@ df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info,
 	  unsigned int regno = DF_REF_REGNO (def);
 	  unsigned int begin = DF_DEFS_BEGIN (regno);
 	  unsigned int n_defs = DF_DEFS_COUNT (regno);
-	  
+
 	  if ((!(df->changeable_flags & DF_NO_HARD_REGS))
 	      || (regno >= FIRST_PSEUDO_REGISTER))
 	    {
 	      /* Only the last def(s) for a regno in the block has any
-		 effect.  */ 
+		 effect.  */
 	      if (!bitmap_bit_p (seen_in_block, regno))
 		{
 		  /* The first def for regno in insn gets to knock out the
@@ -398,7 +377,7 @@ df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info,
 		  if ((!bitmap_bit_p (seen_in_insn, regno))
 		      /* If the def is to only part of the reg, it does
 			 not kill the other defs that reach here.  */
-		      && (!(DF_REF_FLAGS (def) & 
+		      && (!(DF_REF_FLAGS (def) &
 			    (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))))
 		    {
 		      if (n_defs > DF_SPARSE_THRESHOLD)
@@ -412,11 +391,11 @@ df_rd_bb_local_compute_process_def (struct df_rd_bb_info *bb_info,
 			  bitmap_clear_range (bb_info->gen, begin, n_defs);
 			}
 		    }
-		  
+
 		  bitmap_set_bit (seen_in_insn, regno);
 		  /* All defs for regno in the instruction may be put into
 		     the gen set.  */
-		  if (!(DF_REF_FLAGS (def) 
+		  if (!(DF_REF_FLAGS (def)
 			& (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)))
 		    bitmap_set_bit (bb_info->gen, DF_REF_ID (def));
 		}
@@ -440,7 +419,7 @@ df_rd_bb_local_compute (unsigned int bb_index)
 
   /* Artificials are only hard regs.  */
   if (!(df->changeable_flags & DF_NO_HARD_REGS))
-    df_rd_bb_local_compute_process_def (bb_info, 
+    df_rd_bb_local_compute_process_def (bb_info,
 					df_get_artificial_defs (bb_index),
 					0);
 
@@ -451,7 +430,7 @@ df_rd_bb_local_compute (unsigned int bb_index)
       if (!INSN_P (insn))
 	continue;
 
-      df_rd_bb_local_compute_process_def (bb_info, 
+      df_rd_bb_local_compute_process_def (bb_info,
 					  DF_INSN_UID_DEFS (uid), 0);
 
       /* This complex dance with the two bitmaps is required because
@@ -468,7 +447,7 @@ df_rd_bb_local_compute (unsigned int bb_index)
      are going backwards through the block and these are logically at
      the start.  */
   if (!(df->changeable_flags & DF_NO_HARD_REGS))
-    df_rd_bb_local_compute_process_def (bb_info, 
+    df_rd_bb_local_compute_process_def (bb_info,
 					df_get_artificial_defs (bb_index),
 					DF_REF_AT_TOP);
 }
@@ -487,7 +466,8 @@ df_rd_local_compute (bitmap all_blocks)
   bitmap sparse_invalidated = problem_data->sparse_invalidated_by_call;
   bitmap dense_invalidated = problem_data->dense_invalidated_by_call;
 
-  df_set_seen ();
+  seen_in_block = BITMAP_ALLOC (&df_bitmap_obstack);
+  seen_in_insn = BITMAP_ALLOC (&df_bitmap_obstack);
 
   df_maybe_reorganize_def_refs (DF_REF_ORDER_BY_REG);
 
@@ -495,24 +475,26 @@ df_rd_local_compute (bitmap all_blocks)
     {
       df_rd_bb_local_compute (bb_index);
     }
-  
+
   /* Set up the knockout bit vectors to be applied across EH_EDGES.  */
   EXECUTE_IF_SET_IN_BITMAP (regs_invalidated_by_call_regset, 0, regno, bi)
     {
       if (DF_DEFS_COUNT (regno) > DF_SPARSE_THRESHOLD)
 	bitmap_set_bit (sparse_invalidated, regno);
       else
-	bitmap_set_range (dense_invalidated, 
-			  DF_DEFS_BEGIN (regno), 
+	bitmap_set_range (dense_invalidated,
+			  DF_DEFS_BEGIN (regno),
 			  DF_DEFS_COUNT (regno));
     }
-  df_unset_seen ();
+
+  BITMAP_FREE (seen_in_block);
+  BITMAP_FREE (seen_in_insn);
 }
 
 
 /* Initialize the solution bit vectors for problem.  */
 
-static void 
+static void
 df_rd_init_solution (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -521,7 +503,7 @@ df_rd_init_solution (bitmap all_blocks)
   EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
     {
       struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb_index);
-      
+
       bitmap_copy (bb_info->out, bb_info->gen);
       bitmap_clear (bb_info->in);
     }
@@ -535,7 +517,7 @@ df_rd_confluence_n (edge e)
   bitmap op1 = df_rd_get_bb_info (e->dest->index)->in;
   bitmap op2 = df_rd_get_bb_info (e->src->index)->out;
 
-  if (e->flags & EDGE_FAKE) 
+  if (e->flags & EDGE_FAKE)
     return;
 
   if (e->flags & EDGE_EH)
@@ -553,8 +535,8 @@ df_rd_confluence_n (edge e)
 
       EXECUTE_IF_SET_IN_BITMAP (sparse_invalidated, 0, regno, bi)
  	{
- 	  bitmap_clear_range (tmp, 
- 			      DF_DEFS_BEGIN (regno), 
+ 	  bitmap_clear_range (tmp,
+ 			      DF_DEFS_BEGIN (regno),
  			      DF_DEFS_COUNT (regno));
 	}
       bitmap_ior_into (op1, tmp);
@@ -581,7 +563,7 @@ df_rd_transfer_function (int bb_index)
 
   if (bitmap_empty_p (sparse_kill))
     return  bitmap_ior_and_compl (out, gen, in, kill);
-  else 
+  else
     {
       struct df_rd_problem_data *problem_data;
       bool changed = false;
@@ -595,8 +577,8 @@ df_rd_transfer_function (int bb_index)
       bitmap_copy (tmp, in);
       EXECUTE_IF_SET_IN_BITMAP (sparse_kill, 0, regno, bi)
 	{
-	  bitmap_clear_range (tmp, 
-			      DF_DEFS_BEGIN (regno), 
+	  bitmap_clear_range (tmp,
+			      DF_DEFS_BEGIN (regno),
 			      DF_DEFS_COUNT (regno));
 	}
       bitmap_and_compl_into (tmp, kill);
@@ -607,7 +589,7 @@ df_rd_transfer_function (int bb_index)
 	  BITMAP_FREE (out);
 	  bb_info->out = tmp;
 	}
-      else 
+      else
 	  BITMAP_FREE (tmp);
       return changed;
     }
@@ -626,7 +608,7 @@ df_rd_free (void)
     {
       free_alloc_pool (df_rd->block_pool);
       bitmap_obstack_release (&problem_data->rd_bitmaps);
-      
+
       df_rd->block_info_size = 0;
       free (df_rd->block_info);
       free (df_rd->problem_data);
@@ -644,8 +626,8 @@ df_rd_start_dump (FILE *file)
     = (struct df_rd_problem_data *) df_rd->problem_data;
   unsigned int m = DF_REG_SIZE(df);
   unsigned int regno;
-  
-  if (!df_rd->block_info) 
+
+  if (!df_rd->block_info)
     return;
 
   fprintf (file, ";; Reaching defs:\n\n");
@@ -657,8 +639,8 @@ df_rd_start_dump (FILE *file)
 
   for (regno = 0; regno < m; regno++)
     if (DF_DEFS_COUNT (regno))
-      fprintf (file, "%d[%d,%d] ", regno, 
-	       DF_DEFS_BEGIN (regno), 
+      fprintf (file, "%d[%d,%d] ", regno,
+	       DF_DEFS_BEGIN (regno),
 	       DF_DEFS_COUNT (regno));
   fprintf (file, "\n");
 
@@ -673,7 +655,7 @@ df_rd_top_dump (basic_block bb, FILE *file)
   struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb->index);
   if (!bb_info || !bb_info->in)
     return;
-  
+
   fprintf (file, ";; rd  in  \t(%d)\n", (int) bitmap_count_bits (bb_info->in));
   dump_bitmap (file, bb_info->in);
   fprintf (file, ";; rd  gen \t(%d)\n", (int) bitmap_count_bits (bb_info->gen));
@@ -691,7 +673,7 @@ df_rd_bottom_dump (basic_block bb, FILE *file)
   struct df_rd_bb_info *bb_info = df_rd_get_bb_info (bb->index);
   if (!bb_info || !bb_info->out)
     return;
-  
+
   fprintf (file, ";; rd  out \t(%d)\n", (int) bitmap_count_bits (bb_info->out));
   dump_bitmap (file, bb_info->out);
 }
@@ -708,8 +690,8 @@ static struct df_problem problem_RD =
   df_rd_local_compute,        /* Local compute function.  */
   df_rd_init_solution,        /* Init the solution specific data.  */
   df_worklist_dataflow,       /* Worklist solver.  */
-  NULL,                       /* Confluence operator 0.  */ 
-  df_rd_confluence_n,         /* Confluence operator n.  */ 
+  NULL,                       /* Confluence operator 0.  */
+  df_rd_confluence_n,         /* Confluence operator n.  */
   df_rd_transfer_function,    /* Transfer function.  */
   NULL,                       /* Finalize function.  */
   df_rd_free,                 /* Free all of the problem information.  */
@@ -720,15 +702,14 @@ static struct df_problem problem_RD =
   NULL,                       /* Incremental solution verify start.  */
   NULL,                       /* Incremental solution verify end.  */
   NULL,                       /* Dependent problem.  */
-  TV_DF_RD,                   /* Timing variable.  */ 
+  TV_DF_RD,                   /* Timing variable.  */
   true                        /* Reset blocks on dropping out of blocks_to_analyze.  */
 };
 
 
 
-/* Create a new DATAFLOW instance and add it to an existing instance
-   of DF.  The returned structure is what is used to get at the
-   solution.  */
+/* Create a new RD instance and add it to the existing instance
+   of DF.  */
 
 void
 df_rd_add_problem (void)
@@ -758,7 +739,7 @@ struct df_lr_problem_data
 /* Set basic block info.  */
 
 static void
-df_lr_set_bb_info (unsigned int index, 
+df_lr_set_bb_info (unsigned int index,
 		   struct df_lr_bb_info *bb_info)
 {
   gcc_assert (df_lr);
@@ -766,11 +747,11 @@ df_lr_set_bb_info (unsigned int index,
   df_lr->block_info[index] = bb_info;
 }
 
- 
+
 /* Free basic block info.  */
 
 static void
-df_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, 
+df_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 		    void *vbb_info)
 {
   struct df_lr_bb_info *bb_info = (struct df_lr_bb_info *) vbb_info;
@@ -788,14 +769,14 @@ df_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 /* Allocate or reset bitmaps for DF_LR blocks. The solution bits are
    not touched unless the block is new.  */
 
-static void 
+static void
 df_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 {
   unsigned int bb_index;
   bitmap_iterator bi;
 
   if (!df_lr->block_pool)
-    df_lr->block_pool = create_alloc_pool ("df_lr_block pool", 
+    df_lr->block_pool = create_alloc_pool ("df_lr_block pool",
 					   sizeof (struct df_lr_bb_info), 50);
 
   df_grow_bb_info (df_lr);
@@ -804,12 +785,12 @@ df_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
     {
       struct df_lr_bb_info *bb_info = df_lr_get_bb_info (bb_index);
       if (bb_info)
-	{ 
+	{
 	  bitmap_clear (bb_info->def);
 	  bitmap_clear (bb_info->use);
 	}
       else
-	{ 
+	{
 	  bb_info = (struct df_lr_bb_info *) pool_alloc (df_lr->block_pool);
 	  df_lr_set_bb_info (bb_index, bb_info);
 	  bb_info->use = BITMAP_ALLOC (NULL);
@@ -825,7 +806,7 @@ df_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 
 /* Reset the global solution for recalculation.  */
 
-static void 
+static void
 df_lr_reset (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -877,8 +858,8 @@ df_lr_bb_local_compute (unsigned int bb_index)
     {
       unsigned int uid = INSN_UID (insn);
 
-      if (!INSN_P (insn))
-	continue;	
+      if (!NONDEBUG_INSN_P (insn))
+	continue;
 
       for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
 	{
@@ -914,7 +895,7 @@ df_lr_bb_local_compute (unsigned int bb_index)
 	  bitmap_clear_bit (bb_info->use, dregno);
 	}
     }
-  
+
 #ifdef EH_USES
   /* Process the uses that are live into an exception handler.  */
   for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
@@ -942,12 +923,12 @@ df_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
 {
   unsigned int bb_index;
   bitmap_iterator bi;
-    
+
   bitmap_clear (df->hardware_regs_used);
-  
+
   /* The all-important stack pointer must always be live.  */
   bitmap_set_bit (df->hardware_regs_used, STACK_POINTER_REGNUM);
-  
+
   /* Before reload, there are a few registers that must be forced
      live everywhere -- which might not already be the case for
      blocks within infinite loops.  */
@@ -956,21 +937,21 @@ df_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
       /* Any reference to any pseudo before reload is a potential
 	 reference of the frame pointer.  */
       bitmap_set_bit (df->hardware_regs_used, FRAME_POINTER_REGNUM);
-      
+
 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
       /* Pseudos with argument area equivalences may require
 	 reloading via the argument pointer.  */
       if (fixed_regs[ARG_POINTER_REGNUM])
 	bitmap_set_bit (df->hardware_regs_used, ARG_POINTER_REGNUM);
 #endif
-      
+
       /* Any constant, or pseudo with constant equivalences, may
 	 require reloading from memory using the pic register.  */
       if ((unsigned) PIC_OFFSET_TABLE_REGNUM != INVALID_REGNUM
 	  && fixed_regs[PIC_OFFSET_TABLE_REGNUM])
 	bitmap_set_bit (df->hardware_regs_used, PIC_OFFSET_TABLE_REGNUM);
     }
-  
+
   EXECUTE_IF_SET_IN_BITMAP (df_lr->out_of_date_transfer_functions, 0, bb_index, bi)
     {
       if (bb_index == EXIT_BLOCK)
@@ -990,7 +971,7 @@ df_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
 
 /* Initialize the solution vectors.  */
 
-static void 
+static void
 df_lr_init (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -1014,7 +995,7 @@ df_lr_confluence_0 (basic_block bb)
   bitmap op1 = df_lr_get_bb_info (bb->index)->out;
   if (bb != EXIT_BLOCK_PTR)
     bitmap_copy (op1, df->hardware_regs_used);
-} 
+}
 
 
 /* Confluence function that ignores fake edges.  */
@@ -1024,7 +1005,7 @@ df_lr_confluence_n (edge e)
 {
   bitmap op1 = df_lr_get_bb_info (e->src->index)->out;
   bitmap op2 = df_lr_get_bb_info (e->dest->index)->in;
- 
+
   /* Call-clobbered registers die across exception and call edges.  */
   /* ??? Abnormal call edges ignored for the moment, as this gets
      confused by sibling call edges, which crashes reg-stack.  */
@@ -1034,7 +1015,7 @@ df_lr_confluence_n (edge e)
     bitmap_ior_into (op1, op2);
 
   bitmap_ior_into (op1, df->hardware_regs_used);
-} 
+}
 
 
 /* Transfer function.  */
@@ -1106,7 +1087,7 @@ df_lr_free (void)
 	    }
 	}
       free_alloc_pool (df_lr->block_pool);
-      
+
       df_lr->block_info_size = 0;
       free (df_lr->block_info);
     }
@@ -1125,7 +1106,7 @@ df_lr_top_dump (basic_block bb, FILE *file)
   struct df_lr_problem_data *problem_data;
   if (!bb_info || !bb_info->in)
     return;
-      
+
   fprintf (file, ";; lr  in  \t");
   df_print_regset (file, bb_info->in);
   if (df_lr->problem_data)
@@ -1138,7 +1119,7 @@ df_lr_top_dump (basic_block bb, FILE *file)
   df_print_regset (file, bb_info->use);
   fprintf (file, ";; lr  def \t");
   df_print_regset (file, bb_info->def);
-}  
+}
 
 
 /* Debugging info at bottom of bb.  */
@@ -1150,7 +1131,7 @@ df_lr_bottom_dump (basic_block bb, FILE *file)
   struct df_lr_problem_data *problem_data;
   if (!bb_info || !bb_info->out)
     return;
-  
+
   fprintf (file, ";; lr  out \t");
   df_print_regset (file, bb_info->out);
   if (df_lr->problem_data)
@@ -1159,7 +1140,7 @@ df_lr_bottom_dump (basic_block bb, FILE *file)
       fprintf (file, ";;  old out  \t");
       df_print_regset (file, problem_data->out[bb->index]);
     }
-}  
+}
 
 
 /* Build the datastructure to verify that the solution to the dataflow
@@ -1176,7 +1157,7 @@ df_lr_verify_solution_start (void)
       return;
     }
 
-  /* Set it true so that the solution is recomputed.  */ 
+  /* Set it true so that the solution is recomputed.  */
   df_lr->solutions_dirty = true;
 
   problem_data = XNEW (struct df_lr_problem_data);
@@ -1250,8 +1231,8 @@ static struct df_problem problem_LR =
   df_lr_local_compute,        /* Local compute function.  */
   df_lr_init,                 /* Init the solution specific data.  */
   df_worklist_dataflow,       /* Worklist solver.  */
-  df_lr_confluence_0,         /* Confluence operator 0.  */ 
-  df_lr_confluence_n,         /* Confluence operator n.  */ 
+  df_lr_confluence_0,         /* Confluence operator 0.  */
+  df_lr_confluence_n,         /* Confluence operator n.  */
   df_lr_transfer_function,    /* Transfer function.  */
   df_lr_finalize,             /* Finalize function.  */
   df_lr_free,                 /* Free all of the problem information.  */
@@ -1262,7 +1243,7 @@ static struct df_problem problem_LR =
   df_lr_verify_solution_start,/* Incremental solution verify start.  */
   df_lr_verify_solution_end,  /* Incremental solution verify end.  */
   NULL,                       /* Dependent problem.  */
-  TV_DF_LR,                   /* Timing variable.  */ 
+  TV_DF_LR,                   /* Timing variable.  */
   false                       /* Reset blocks on dropping out of blocks_to_analyze.  */
 };
 
@@ -1313,7 +1294,7 @@ df_lr_verify_transfer_functions (void)
 	  /* Make a copy of the transfer functions and then compute
 	     new ones to see if the transfer functions have
 	     changed.  */
-	  if (!bitmap_bit_p (df_lr->out_of_date_transfer_functions, 
+	  if (!bitmap_bit_p (df_lr->out_of_date_transfer_functions,
 			     bb->index))
 	    {
 	      bitmap_copy (saved_def, bb_info->def);
@@ -1331,7 +1312,7 @@ df_lr_verify_transfer_functions (void)
 	  /* If we do not have basic block info, the block must be in
 	     the list of dirty blocks or else some one has added a
 	     block behind our backs. */
-	  gcc_assert (bitmap_bit_p (df_lr->out_of_date_transfer_functions, 
+	  gcc_assert (bitmap_bit_p (df_lr->out_of_date_transfer_functions,
 				    bb->index));
 	}
       /* Make sure no one created a block without following
@@ -1340,8 +1321,8 @@ df_lr_verify_transfer_functions (void)
     }
 
   /* Make sure there are no dirty bits in blocks that have been deleted.  */
-  gcc_assert (!bitmap_intersect_compl_p (df_lr->out_of_date_transfer_functions, 
-					 all_blocks)); 
+  gcc_assert (!bitmap_intersect_compl_p (df_lr->out_of_date_transfer_functions,
+					 all_blocks));
 
   BITMAP_FREE (saved_def);
   BITMAP_FREE (saved_use);
@@ -1368,7 +1349,7 @@ df_lr_verify_transfer_functions (void)
 
    Then, the in and out sets for the LIVE problem itself are computed.
    These are the logical AND of the IN and OUT sets from the LR problem
-   and the must-initialized problem. 
+   and the must-initialized problem.
 ----------------------------------------------------------------------------*/
 
 /* Private data used to verify the solution for this problem.  */
@@ -1386,7 +1367,7 @@ static bitmap df_live_scratch;
 /* Set basic block info.  */
 
 static void
-df_live_set_bb_info (unsigned int index, 
+df_live_set_bb_info (unsigned int index,
 		   struct df_live_bb_info *bb_info)
 {
   gcc_assert (df_live);
@@ -1398,7 +1379,7 @@ df_live_set_bb_info (unsigned int index,
 /* Free basic block info.  */
 
 static void
-df_live_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, 
+df_live_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 		    void *vbb_info)
 {
   struct df_live_bb_info *bb_info = (struct df_live_bb_info *) vbb_info;
@@ -1416,14 +1397,14 @@ df_live_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 /* Allocate or reset bitmaps for DF_LIVE blocks. The solution bits are
    not touched unless the block is new.  */
 
-static void 
+static void
 df_live_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 {
   unsigned int bb_index;
   bitmap_iterator bi;
 
   if (!df_live->block_pool)
-    df_live->block_pool = create_alloc_pool ("df_live_block pool", 
+    df_live->block_pool = create_alloc_pool ("df_live_block pool",
 					   sizeof (struct df_live_bb_info), 100);
   if (!df_live_scratch)
     df_live_scratch = BITMAP_ALLOC (NULL);
@@ -1434,12 +1415,12 @@ df_live_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
     {
       struct df_live_bb_info *bb_info = df_live_get_bb_info (bb_index);
       if (bb_info)
-	{ 
+	{
 	  bitmap_clear (bb_info->kill);
 	  bitmap_clear (bb_info->gen);
 	}
       else
-	{ 
+	{
 	  bb_info = (struct df_live_bb_info *) pool_alloc (df_live->block_pool);
 	  df_live_set_bb_info (bb_index, bb_info);
 	  bb_info->kill = BITMAP_ALLOC (NULL);
@@ -1454,7 +1435,7 @@ df_live_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 
 /* Reset the global solution for recalculation.  */
 
-static void 
+static void
 df_live_reset (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -1536,7 +1517,7 @@ df_live_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
 
   df_grow_insn_info ();
 
-  EXECUTE_IF_SET_IN_BITMAP (df_live->out_of_date_transfer_functions, 
+  EXECUTE_IF_SET_IN_BITMAP (df_live->out_of_date_transfer_functions,
 			    0, bb_index, bi)
     {
       df_live_bb_local_compute (bb_index);
@@ -1548,7 +1529,7 @@ df_live_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
 
 /* Initialize the solution vectors.  */
 
-static void 
+static void
 df_live_init (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -1573,12 +1554,12 @@ df_live_confluence_n (edge e)
 {
   bitmap op1 = df_live_get_bb_info (e->dest->index)->in;
   bitmap op2 = df_live_get_bb_info (e->src->index)->out;
- 
-  if (e->flags & EDGE_FAKE) 
+
+  if (e->flags & EDGE_FAKE)
     return;
 
   bitmap_ior_into (op1, op2);
-} 
+}
 
 
 /* Transfer function for the forwards must-initialized problem.  */
@@ -1593,10 +1574,9 @@ df_live_transfer_function (int bb_index)
   bitmap gen = bb_info->gen;
   bitmap kill = bb_info->kill;
 
-  /* We need to use a scratch set here so that the value returned from
-     this function invocation properly reflects if the sets changed in
-     a significant way; i.e. not just because the lr set was anded
-     in.  */
+  /* We need to use a scratch set here so that the value returned from this
+     function invocation properly reflects whether the sets changed in a
+     significant way; i.e. not just because the lr set was anded in.  */
   bitmap_and (df_live_scratch, gen, bb_lr_info->out);
   /* No register may reach a location where it is not used.  Thus
      we trim the rr result to the places where it is used.  */
@@ -1621,13 +1601,13 @@ df_live_finalize (bitmap all_blocks)
 	{
 	  struct df_lr_bb_info *bb_lr_info = df_lr_get_bb_info (bb_index);
 	  struct df_live_bb_info *bb_live_info = df_live_get_bb_info (bb_index);
-  
+
 	  /* No register may reach a location where it is not used.  Thus
 	     we trim the rr result to the places where it is used.  */
 	  bitmap_and_into (bb_live_info->in, bb_lr_info->in);
 	  bitmap_and_into (bb_live_info->out, bb_lr_info->out);
 	}
-      
+
       df_live->solutions_dirty = false;
     }
 }
@@ -1641,7 +1621,7 @@ df_live_free (void)
   if (df_live->block_info)
     {
       unsigned int i;
-      
+
       for (i = 0; i < df_live->block_info_size; i++)
 	{
 	  struct df_live_bb_info *bb_info = df_live_get_bb_info (i);
@@ -1653,7 +1633,7 @@ df_live_free (void)
 	      BITMAP_FREE (bb_info->out);
 	    }
 	}
-      
+
       free_alloc_pool (df_live->block_pool);
       df_live->block_info_size = 0;
       free (df_live->block_info);
@@ -1676,7 +1656,7 @@ df_live_top_dump (basic_block bb, FILE *file)
 
   if (!bb_info || !bb_info->in)
     return;
-      
+
   fprintf (file, ";; live  in  \t");
   df_print_regset (file, bb_info->in);
   if (df_live->problem_data)
@@ -1702,7 +1682,7 @@ df_live_bottom_dump (basic_block bb, FILE *file)
 
   if (!bb_info || !bb_info->out)
     return;
-      
+
   fprintf (file, ";; live  out \t");
   df_print_regset (file, bb_info->out);
   if (df_live->problem_data)
@@ -1728,7 +1708,7 @@ df_live_verify_solution_start (void)
       return;
     }
 
-  /* Set it true so that the solution is recomputed.  */ 
+  /* Set it true so that the solution is recomputed.  */
   df_live->solutions_dirty = true;
 
   problem_data = XNEW (struct df_live_problem_data);
@@ -1797,8 +1777,8 @@ static struct df_problem problem_LIVE =
   df_live_local_compute,        /* Local compute function.  */
   df_live_init,                 /* Init the solution specific data.  */
   df_worklist_dataflow,         /* Worklist solver.  */
-  NULL,                         /* Confluence operator 0.  */ 
-  df_live_confluence_n,         /* Confluence operator n.  */ 
+  NULL,                         /* Confluence operator 0.  */
+  df_live_confluence_n,         /* Confluence operator n.  */
   df_live_transfer_function,    /* Transfer function.  */
   df_live_finalize,             /* Finalize function.  */
   df_live_free,                 /* Free all of the problem information.  */
@@ -1836,7 +1816,7 @@ df_live_set_all_dirty (void)
 {
   basic_block bb;
   FOR_ALL_BB (bb)
-    bitmap_set_bit (df_live->out_of_date_transfer_functions, 
+    bitmap_set_bit (df_live->out_of_date_transfer_functions,
 		    bb->index);
 }
 
@@ -1871,7 +1851,7 @@ df_live_verify_transfer_functions (void)
 	  /* Make a copy of the transfer functions and then compute
 	     new ones to see if the transfer functions have
 	     changed.  */
-	  if (!bitmap_bit_p (df_live->out_of_date_transfer_functions, 
+	  if (!bitmap_bit_p (df_live->out_of_date_transfer_functions,
 			     bb->index))
 	    {
 	      bitmap_copy (saved_gen, bb_info->gen);
@@ -1889,7 +1869,7 @@ df_live_verify_transfer_functions (void)
 	  /* If we do not have basic block info, the block must be in
 	     the list of dirty blocks or else some one has added a
 	     block behind our backs. */
-	  gcc_assert (bitmap_bit_p (df_live->out_of_date_transfer_functions, 
+	  gcc_assert (bitmap_bit_p (df_live->out_of_date_transfer_functions,
 				    bb->index));
 	}
       /* Make sure no one created a block without following
@@ -1898,8 +1878,8 @@ df_live_verify_transfer_functions (void)
     }
 
   /* Make sure there are no dirty bits in blocks that have been deleted.  */
-  gcc_assert (!bitmap_intersect_compl_p (df_live->out_of_date_transfer_functions, 
-					 all_blocks)); 
+  gcc_assert (!bitmap_intersect_compl_p (df_live->out_of_date_transfer_functions,
+					 all_blocks));
   BITMAP_FREE (saved_gen);
   BITMAP_FREE (saved_kill);
   BITMAP_FREE (all_blocks);
@@ -1925,7 +1905,7 @@ df_chain_create (df_ref src, df_ref dst)
 {
   struct df_link *head = DF_REF_CHAIN (src);
   struct df_link *link = (struct df_link *) pool_alloc (df_chain->block_pool);
-  
+
   DF_REF_CHAIN (src) = link;
   link->next = head;
   link->ref = dst;
@@ -1934,7 +1914,7 @@ df_chain_create (df_ref src, df_ref dst)
 
 
 /* Delete any du or ud chains that start at REF and point to
-   TARGET.  */ 
+   TARGET.  */
 static void
 df_chain_unlink_1 (df_ref ref, df_ref target)
 {
@@ -1977,10 +1957,10 @@ df_chain_unlink (df_ref ref)
 
 
 /* Copy the du or ud chain starting at FROM_REF and attach it to
-   TO_REF.  */ 
+   TO_REF.  */
 
-void 
-df_chain_copy (df_ref to_ref, 
+void
+df_chain_copy (df_ref to_ref,
 	       struct df_link *from_ref)
 {
   while (from_ref)
@@ -1999,7 +1979,7 @@ df_chain_remove_problem (void)
   bitmap_iterator bi;
   unsigned int bb_index;
 
-  /* Wholesale destruction of the old chains.  */ 
+  /* Wholesale destruction of the old chains.  */
   if (df_chain->block_pool)
     free_alloc_pool (df_chain->block_pool);
 
@@ -2016,11 +1996,11 @@ df_chain_remove_problem (void)
       if (df_chain_problem_p (DF_UD_CHAIN))
 	for (use_rec = df_get_artificial_uses (bb->index); *use_rec; use_rec++)
 	  DF_REF_CHAIN (*use_rec) = NULL;
-      
+
       FOR_BB_INSNS (bb, insn)
 	{
 	  unsigned int uid = INSN_UID (insn);
-	  
+
 	  if (INSN_P (insn))
 	    {
 	      if (df_chain_problem_p (DF_DU_CHAIN))
@@ -2055,11 +2035,11 @@ df_chain_fully_remove_problem (void)
 
 /* Create def-use or use-def chains.  */
 
-static void  
+static void
 df_chain_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 {
   df_chain_remove_problem ();
-  df_chain->block_pool = create_alloc_pool ("df_chain_block pool", 
+  df_chain->block_pool = create_alloc_pool ("df_chain_block pool",
 					 sizeof (struct df_link), 50);
   df_chain->optional_p = true;
 }
@@ -2083,7 +2063,7 @@ df_chain_create_bb_process_use (bitmap local_rd,
 {
   bitmap_iterator bi;
   unsigned int def_index;
-  
+
   while (*use_rec)
     {
       df_ref use = *use_rec;
@@ -2099,13 +2079,13 @@ df_chain_create_bb_process_use (bitmap local_rd,
 		{
 		  unsigned int first_index = DF_DEFS_BEGIN (uregno);
 		  unsigned int last_index = first_index + count - 1;
-		  
+
 		  EXECUTE_IF_SET_IN_BITMAP (local_rd, first_index, def_index, bi)
 		    {
 		      df_ref def;
-		      if (def_index > last_index) 
+		      if (def_index > last_index)
 			break;
-		      
+
 		      def = DF_DEFS_GET (def_index);
 		      if (df_chain_problem_p (DF_DU_CHAIN))
 			df_chain_create (def, use);
@@ -2140,16 +2120,16 @@ df_chain_create_bb (unsigned int bb_index)
 #ifdef EH_USES
   /* Create the chains for the artificial uses from the EH_USES at the
      beginning of the block.  */
-  
+
   /* Artificials are only hard regs.  */
   if (!(df->changeable_flags & DF_NO_HARD_REGS))
     df_chain_create_bb_process_use (cpy,
-				    df_get_artificial_uses (bb->index), 
+				    df_get_artificial_uses (bb->index),
 				    DF_REF_AT_TOP);
 #endif
 
   df_rd_simulate_artificial_defs_at_top (bb, cpy);
-  
+
   /* Process the regular instructions next.  */
   FOR_BB_INSNS (bb, insn)
     if (INSN_P (insn))
@@ -2170,7 +2150,7 @@ df_chain_create_bb (unsigned int bb_index)
      at the end of the block.  */
   if (!(df->changeable_flags & DF_NO_HARD_REGS))
     df_chain_create_bb_process_use (cpy,
-				    df_get_artificial_uses (bb->index), 
+				    df_get_artificial_uses (bb->index),
 				    0);
 
   BITMAP_FREE (cpy);
@@ -2184,7 +2164,7 @@ df_chain_finalize (bitmap all_blocks)
 {
   unsigned int bb_index;
   bitmap_iterator bi;
-  
+
   EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
     {
       df_chain_create_bb (bb_index);
@@ -2214,7 +2194,7 @@ df_chain_top_dump (basic_block bb, FILE *file)
       df_ref *def_rec = df_get_artificial_defs (bb->index);
       if (*def_rec)
 	{
-	  
+
 	  fprintf (file, ";;  DU chains for artificial defs\n");
 	  while (*def_rec)
 	    {
@@ -2224,7 +2204,7 @@ df_chain_top_dump (basic_block bb, FILE *file)
 	      fprintf (file, "\n");
 	      def_rec++;
 	    }
-	}      
+	}
 
       FOR_BB_INSNS (bb, insn)
 	{
@@ -2234,9 +2214,9 @@ df_chain_top_dump (basic_block bb, FILE *file)
 	      def_rec = DF_INSN_INFO_DEFS (insn_info);
 	      if (*def_rec)
 		{
-		  fprintf (file, ";;   DU chains for insn luid %d uid %d\n", 
+		  fprintf (file, ";;   DU chains for insn luid %d uid %d\n",
 			   DF_INSN_INFO_LUID (insn_info), INSN_UID (insn));
-		  
+
 		  while (*def_rec)
 		    {
 		      df_ref def = *def_rec;
@@ -2273,7 +2253,7 @@ df_chain_bottom_dump (basic_block bb, FILE *file)
 	      fprintf (file, "\n");
 	      use_rec++;
 	    }
-	}      
+	}
 
       FOR_BB_INSNS (bb, insn)
 	{
@@ -2284,9 +2264,9 @@ df_chain_bottom_dump (basic_block bb, FILE *file)
 	      use_rec = DF_INSN_INFO_USES (insn_info);
 	      if (*use_rec || *eq_use_rec)
 		{
-		  fprintf (file, ";;   UD chains for insn luid %d uid %d\n", 
+		  fprintf (file, ";;   UD chains for insn luid %d uid %d\n",
 			   DF_INSN_INFO_LUID (insn_info), INSN_UID (insn));
-		  
+
 		  while (*use_rec)
 		    {
 		      df_ref use = *use_rec;
@@ -2322,8 +2302,8 @@ static struct df_problem problem_CHAIN =
   NULL,                       /* Local compute function.  */
   NULL,                       /* Init the solution specific data.  */
   NULL,                       /* Iterative solver.  */
-  NULL,                       /* Confluence operator 0.  */ 
-  NULL,                       /* Confluence operator n.  */ 
+  NULL,                       /* Confluence operator 0.  */
+  NULL,                       /* Confluence operator n.  */
   NULL,                       /* Transfer function.  */
   df_chain_finalize,          /* Finalize function.  */
   df_chain_free,              /* Free all of the problem information.  */
@@ -2396,8 +2376,8 @@ struct df_byte_lr_problem_data
   bitmap needs_expansion;
 
   /* The start position and len for each regno in the various bit
-     vectors.  */ 
-  unsigned int* regno_start;  
+     vectors.  */
+  unsigned int* regno_start;
   unsigned int* regno_len;
   /* An obstack for the bitmaps we need for this problem.  */
   bitmap_obstack byte_lr_bitmaps;
@@ -2406,10 +2386,10 @@ struct df_byte_lr_problem_data
 
 /* Get the starting location for REGNO in the df_byte_lr bitmaps.  */
 
-int 
+int
 df_byte_lr_get_regno_start (unsigned int regno)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;;
   return problem_data->regno_start[regno];
 }
@@ -2417,10 +2397,10 @@ df_byte_lr_get_regno_start (unsigned int regno)
 
 /* Get the len for REGNO in the df_byte_lr bitmaps.  */
 
-int 
+int
 df_byte_lr_get_regno_len (unsigned int regno)
-{  
-  struct df_byte_lr_problem_data *problem_data 
+{
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;;
   return problem_data->regno_len[regno];
 }
@@ -2429,7 +2409,7 @@ df_byte_lr_get_regno_len (unsigned int regno)
 /* Set basic block info.  */
 
 static void
-df_byte_lr_set_bb_info (unsigned int index, 
+df_byte_lr_set_bb_info (unsigned int index,
 			struct df_byte_lr_bb_info *bb_info)
 {
   gcc_assert (df_byte_lr);
@@ -2437,11 +2417,11 @@ df_byte_lr_set_bb_info (unsigned int index,
   df_byte_lr->block_info[index] = bb_info;
 }
 
- 
+
 /* Free basic block info.  */
 
 static void
-df_byte_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED, 
+df_byte_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 			 void *vbb_info)
 {
   struct df_byte_lr_bb_info *bb_info = (struct df_byte_lr_bb_info *) vbb_info;
@@ -2462,14 +2442,14 @@ df_byte_lr_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
 static void
 df_byte_lr_check_regs (df_ref *ref_rec)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
 
   for (; *ref_rec; ref_rec++)
     {
       df_ref ref = *ref_rec;
-      if (DF_REF_FLAGS_IS_SET (ref, DF_REF_SIGN_EXTRACT 
-			       | DF_REF_ZERO_EXTRACT 
+      if (DF_REF_FLAGS_IS_SET (ref, DF_REF_SIGN_EXTRACT
+			       | DF_REF_ZERO_EXTRACT
 			       | DF_REF_STRICT_LOW_PART)
 	  || GET_CODE (DF_REF_REG (ref)) == SUBREG)
 	bitmap_set_bit (problem_data->needs_expansion, DF_REF_REGNO (ref));
@@ -2477,13 +2457,13 @@ df_byte_lr_check_regs (df_ref *ref_rec)
 }
 
 
-/* Expand bitmap SRC which is indexed by regno to DEST which is indexed by 
+/* Expand bitmap SRC which is indexed by regno to DEST which is indexed by
    regno_start and regno_len.  */
 
 static void
 df_byte_lr_expand_bitmap (bitmap dest, bitmap src)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   bitmap_iterator bi;
   unsigned int i;
@@ -2491,7 +2471,7 @@ df_byte_lr_expand_bitmap (bitmap dest, bitmap src)
   bitmap_clear (dest);
   EXECUTE_IF_SET_IN_BITMAP (src, 0, i, bi)
     {
-      bitmap_set_range (dest, problem_data->regno_start[i], 
+      bitmap_set_range (dest, problem_data->regno_start[i],
 			problem_data->regno_len[i]);
     }
 }
@@ -2500,7 +2480,7 @@ df_byte_lr_expand_bitmap (bitmap dest, bitmap src)
 /* Allocate or reset bitmaps for DF_BYTE_LR blocks. The solution bits are
    not touched unless the block is new.  */
 
-static void 
+static void
 df_byte_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 {
   unsigned int bb_index;
@@ -2515,7 +2495,7 @@ df_byte_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
   df_byte_lr->problem_data = problem_data;
 
   if (!df_byte_lr->block_pool)
-    df_byte_lr->block_pool = create_alloc_pool ("df_byte_lr_block pool", 
+    df_byte_lr->block_pool = create_alloc_pool ("df_byte_lr_block pool",
 					   sizeof (struct df_byte_lr_bb_info), 50);
 
   df_grow_bb_info (df_byte_lr);
@@ -2532,7 +2512,7 @@ df_byte_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
   problem_data->hardware_regs_used = BITMAP_ALLOC (&problem_data->byte_lr_bitmaps);
   problem_data->invalidated_by_call = BITMAP_ALLOC (&problem_data->byte_lr_bitmaps);
   problem_data->needs_expansion = BITMAP_ALLOC (&problem_data->byte_lr_bitmaps);
-  
+
   /* Discover which regno's use subregs, extracts or
      strict_low_parts.  */
   FOR_EACH_BB (bb)
@@ -2552,7 +2532,7 @@ df_byte_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 
   bitmap_set_bit (df_byte_lr->out_of_date_transfer_functions, ENTRY_BLOCK);
   bitmap_set_bit (df_byte_lr->out_of_date_transfer_functions, EXIT_BLOCK);
-  
+
   /* Allocate the slots for each regno.  */
   for (regno = 0; regno < max_reg; regno++)
     {
@@ -2560,28 +2540,28 @@ df_byte_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
       problem_data->regno_start[regno] = index;
       if (bitmap_bit_p (problem_data->needs_expansion, regno))
 	len = GET_MODE_SIZE (GET_MODE (regno_reg_rtx[regno]));
-      else 
+      else
 	len = 1;
-      
+
       problem_data->regno_len[regno] = len;
       index += len;
     }
 
-  df_byte_lr_expand_bitmap (problem_data->hardware_regs_used, 
+  df_byte_lr_expand_bitmap (problem_data->hardware_regs_used,
 			    df->hardware_regs_used);
-  df_byte_lr_expand_bitmap (problem_data->invalidated_by_call, 
+  df_byte_lr_expand_bitmap (problem_data->invalidated_by_call,
 			    regs_invalidated_by_call_regset);
 
   EXECUTE_IF_SET_IN_BITMAP (df_byte_lr->out_of_date_transfer_functions, 0, bb_index, bi)
     {
       struct df_byte_lr_bb_info *bb_info = df_byte_lr_get_bb_info (bb_index);
       if (bb_info)
-	{ 
+	{
 	  bitmap_clear (bb_info->def);
 	  bitmap_clear (bb_info->use);
 	}
       else
-	{ 
+	{
 	  bb_info = (struct df_byte_lr_bb_info *) pool_alloc (df_byte_lr->block_pool);
 	  df_byte_lr_set_bb_info (bb_index, bb_info);
 	  bb_info->use = BITMAP_ALLOC (&problem_data->byte_lr_bitmaps);
@@ -2590,14 +2570,14 @@ df_byte_lr_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 	  bb_info->out = BITMAP_ALLOC (&problem_data->byte_lr_bitmaps);
 	}
     }
-  
+
   df_byte_lr->optional_p = true;
 }
 
 
 /* Reset the global solution for recalculation.  */
 
-static void 
+static void
 df_byte_lr_reset (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -2618,7 +2598,7 @@ df_byte_lr_reset (bitmap all_blocks)
 static void
 df_byte_lr_bb_local_compute (unsigned int bb_index)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   basic_block bb = BASIC_BLOCK (bb_index);
   struct df_byte_lr_bb_info *bb_info = df_byte_lr_get_bb_info (bb_index);
@@ -2659,7 +2639,7 @@ df_byte_lr_bb_local_compute (unsigned int bb_index)
       unsigned int uid = INSN_UID (insn);
 
       if (!INSN_P (insn))
-	continue;	
+	continue;
 
       for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
 	{
@@ -2720,7 +2700,7 @@ df_byte_lr_bb_local_compute (unsigned int bb_index)
 	  bitmap_clear_range (bb_info->use, start, len);
 	}
     }
-  
+
 #ifdef EH_USES
   /* Process the uses that are live into an exception handler.  */
   for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
@@ -2766,7 +2746,7 @@ df_byte_lr_local_compute (bitmap all_blocks ATTRIBUTE_UNUSED)
 
 /* Initialize the solution vectors.  */
 
-static void 
+static void
 df_byte_lr_init (bitmap all_blocks)
 {
   unsigned int bb_index;
@@ -2787,12 +2767,12 @@ df_byte_lr_init (bitmap all_blocks)
 static void
 df_byte_lr_confluence_0 (basic_block bb)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   bitmap op1 = df_byte_lr_get_bb_info (bb->index)->out;
   if (bb != EXIT_BLOCK_PTR)
     bitmap_copy (op1, problem_data->hardware_regs_used);
-} 
+}
 
 
 /* Confluence function that ignores fake edges.  */
@@ -2800,11 +2780,11 @@ df_byte_lr_confluence_0 (basic_block bb)
 static void
 df_byte_lr_confluence_n (edge e)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   bitmap op1 = df_byte_lr_get_bb_info (e->src->index)->out;
   bitmap op2 = df_byte_lr_get_bb_info (e->dest->index)->in;
- 
+
   /* Call-clobbered registers die across exception and call edges.  */
   /* ??? Abnormal call edges ignored for the moment, as this gets
      confused by sibling call edges, which crashes reg-stack.  */
@@ -2814,7 +2794,7 @@ df_byte_lr_confluence_n (edge e)
     bitmap_ior_into (op1, op2);
 
   bitmap_ior_into (op1, problem_data->hardware_regs_used);
-} 
+}
 
 
 /* Transfer function.  */
@@ -2865,14 +2845,14 @@ df_byte_lr_top_dump (basic_block bb, FILE *file)
   struct df_byte_lr_bb_info *bb_info = df_byte_lr_get_bb_info (bb->index);
   if (!bb_info || !bb_info->in)
     return;
-      
+
   fprintf (file, ";; blr  in  \t");
   df_print_byte_regset (file, bb_info->in);
   fprintf (file, ";; blr  use \t");
   df_print_byte_regset (file, bb_info->use);
   fprintf (file, ";; blr  def \t");
   df_print_byte_regset (file, bb_info->def);
-}  
+}
 
 
 /* Debugging info at bottom of bb.  */
@@ -2883,10 +2863,10 @@ df_byte_lr_bottom_dump (basic_block bb, FILE *file)
   struct df_byte_lr_bb_info *bb_info = df_byte_lr_get_bb_info (bb->index);
   if (!bb_info || !bb_info->out)
     return;
-  
+
   fprintf (file, ";; blr  out \t");
   df_print_byte_regset (file, bb_info->out);
-}  
+}
 
 
 /* All of the information associated with every instance of the problem.  */
@@ -2901,8 +2881,8 @@ static struct df_problem problem_BYTE_LR =
   df_byte_lr_local_compute,        /* Local compute function.  */
   df_byte_lr_init,                 /* Init the solution specific data.  */
   df_worklist_dataflow,            /* Worklist solver.  */
-  df_byte_lr_confluence_0,         /* Confluence operator 0.  */ 
-  df_byte_lr_confluence_n,         /* Confluence operator n.  */ 
+  df_byte_lr_confluence_0,         /* Confluence operator 0.  */
+  df_byte_lr_confluence_n,         /* Confluence operator n.  */
   df_byte_lr_transfer_function,    /* Transfer function.  */
   NULL,                            /* Finalize function.  */
   df_byte_lr_free,                 /* Free all of the problem information.  */
@@ -2913,7 +2893,7 @@ static struct df_problem problem_BYTE_LR =
   NULL,                            /* Incremental solution verify start.  */
   NULL,                            /* Incremental solution verify end.  */
   NULL,                            /* Dependent problem.  */
-  TV_DF_BYTE_LR,                   /* Timing variable.  */ 
+  TV_DF_BYTE_LR,                   /* Timing variable.  */
   false                            /* Reset blocks on dropping out of blocks_to_analyze.  */
 };
 
@@ -2937,7 +2917,7 @@ df_byte_lr_add_problem (void)
 void
 df_byte_lr_simulate_defs (rtx insn, bitmap live)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   df_ref *def_rec;
   unsigned int uid = INSN_UID (insn);
@@ -2965,15 +2945,15 @@ df_byte_lr_simulate_defs (rtx insn, bitmap live)
 	    bitmap_clear_range (live, start, len);
 	}
     }
-}  
+}
 
 
 /* Simulate the effects of the uses of INSN on LIVE.  */
 
-void 
+void
 df_byte_lr_simulate_uses (rtx insn, bitmap live)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   df_ref *use_rec;
   unsigned int uid = INSN_UID (insn);
@@ -2986,13 +2966,13 @@ df_byte_lr_simulate_uses (rtx insn, bitmap live)
       unsigned int len = problem_data->regno_len[uregno];
       unsigned int sb;
       unsigned int lb;
-      
+
       if (!df_compute_accessed_bytes (use, DF_MM_MAY, &sb, &lb))
 	{
 	  start += sb;
 	  len = lb - sb;
 	}
-      
+
       /* Add use to set of uses in this BB.  */
       if (len)
 	bitmap_set_range (live, start, len);
@@ -3003,17 +2983,17 @@ df_byte_lr_simulate_uses (rtx insn, bitmap live)
 /* Apply the artificial uses and defs at the top of BB in a forwards
    direction.  */
 
-void 
+void
 df_byte_lr_simulate_artificial_refs_at_top (basic_block bb, bitmap live)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   df_ref *def_rec;
 #ifdef EH_USES
   df_ref *use_rec;
 #endif
   int bb_index = bb->index;
-  
+
 #ifdef EH_USES
   for (use_rec = df_get_artificial_uses (bb_index); *use_rec; use_rec++)
     {
@@ -3032,7 +3012,7 @@ df_byte_lr_simulate_artificial_refs_at_top (basic_block bb, bitmap live)
     {
       df_ref def = *def_rec;
       if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
-	{      
+	{
 	  unsigned int dregno = DF_REF_REGNO (def);
 	  unsigned int start = problem_data->regno_start[dregno];
 	  unsigned int len = problem_data->regno_len[dregno];
@@ -3045,15 +3025,15 @@ df_byte_lr_simulate_artificial_refs_at_top (basic_block bb, bitmap live)
 /* Apply the artificial uses and defs at the end of BB in a backwards
    direction.  */
 
-void 
+void
 df_byte_lr_simulate_artificial_refs_at_end (basic_block bb, bitmap live)
 {
-  struct df_byte_lr_problem_data *problem_data 
+  struct df_byte_lr_problem_data *problem_data
     = (struct df_byte_lr_problem_data *)df_byte_lr->problem_data;
   df_ref *def_rec;
   df_ref *use_rec;
   int bb_index = bb->index;
-  
+
   for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
     {
       df_ref def = *def_rec;
@@ -3085,14 +3065,14 @@ df_byte_lr_simulate_artificial_refs_at_end (basic_block bb, bitmap live)
    This problem computes REG_DEAD and REG_UNUSED notes.
    ----------------------------------------------------------------------------*/
 
-static void 
+static void
 df_note_alloc (bitmap all_blocks ATTRIBUTE_UNUSED)
 {
   df_note->optional_p = true;
 }
 
 #ifdef REG_DEAD_DEBUGGING
-static void 
+static void
 df_print_note (const char *prefix, rtx insn, rtx note)
 {
   if (dump_file)
@@ -3110,14 +3090,14 @@ df_print_note (const char *prefix, rtx insn, rtx note)
    just leave the notes alone. */
 
 #ifdef STACK_REGS
-static inline bool 
+static inline bool
 df_ignore_stack_reg (int regno)
 {
   return regstack_completed
     && IN_RANGE (regno, FIRST_STACK_REG, LAST_STACK_REG);
 }
 #else
-static inline bool 
+static inline bool
 df_ignore_stack_reg (int regno ATTRIBUTE_UNUSED)
 {
   return false;
@@ -3141,7 +3121,7 @@ df_kill_notes (rtx insn, rtx *old_dead_notes, rtx *old_unused_notes)
       switch (REG_NOTE_KIND (link))
 	{
 	case REG_DEAD:
-	  /* After reg-stack, we need to ignore any unused notes 
+	  /* After reg-stack, we need to ignore any unused notes
 	     for the stack registers.  */
 	  if (df_ignore_stack_reg (REGNO (XEXP (link, 0))))
 	    {
@@ -3161,7 +3141,7 @@ df_kill_notes (rtx insn, rtx *old_dead_notes, rtx *old_unused_notes)
 	  break;
 
 	case REG_UNUSED:
-	  /* After reg-stack, we need to ignore any unused notes 
+	  /* After reg-stack, we need to ignore any unused notes
 	     for the stack registers.  */
 	  if (df_ignore_stack_reg (REGNO (XEXP (link, 0))))
 	    {
@@ -3179,7 +3159,7 @@ df_kill_notes (rtx insn, rtx *old_dead_notes, rtx *old_unused_notes)
 	      *pprev = link = next;
 	    }
 	  break;
-	  
+
 	default:
 	  pprev = &XEXP (link, 1);
 	  link = *pprev;
@@ -3201,6 +3181,8 @@ df_set_note (enum reg_note note_type, rtx insn, rtx old, rtx reg)
   rtx curr = old;
   rtx prev = NULL;
 
+  gcc_assert (!DEBUG_INSN_P (insn));
+
   while (curr)
     if (XEXP (curr, 0) == reg)
       {
@@ -3217,7 +3199,7 @@ df_set_note (enum reg_note note_type, rtx insn, rtx old, rtx reg)
 	prev = curr;
 	curr = XEXP (curr, 1);
       }
-  
+
   /* Did not find the note.  */
   add_reg_note (insn, note_type, reg);
   return old;
@@ -3258,14 +3240,14 @@ df_whole_mw_reg_unused_p (struct df_mw_hardreg *mws,
 
 static rtx
 df_set_unused_notes_for_mw (rtx insn, rtx old, struct df_mw_hardreg *mws,
-			    bitmap live, bitmap do_not_gen, 
+			    bitmap live, bitmap do_not_gen,
 			    bitmap artificial_uses)
 {
   unsigned int r;
-  
+
 #ifdef REG_DEAD_DEBUGGING
   if (dump_file)
-    fprintf (dump_file, "mw_set_unused looking at mws[%d..%d]\n", 
+    fprintf (dump_file, "mw_set_unused looking at mws[%d..%d]\n",
 	     mws->start_regno, mws->end_regno);
 #endif
 
@@ -3333,14 +3315,17 @@ df_whole_mw_reg_dead_p (struct df_mw_hardreg *mws,
 static rtx
 df_set_dead_notes_for_mw (rtx insn, rtx old, struct df_mw_hardreg *mws,
 			  bitmap live, bitmap do_not_gen,
-			  bitmap artificial_uses)
+			  bitmap artificial_uses, bool *added_notes_p)
 {
   unsigned int r;
-  
+  bool is_debug = *added_notes_p;
+
+  *added_notes_p = false;
+
 #ifdef REG_DEAD_DEBUGGING
   if (dump_file)
     {
-      fprintf (dump_file, "mw_set_dead looking at mws[%d..%d]\n  do_not_gen =", 
+      fprintf (dump_file, "mw_set_dead looking at mws[%d..%d]\n  do_not_gen =",
 	       mws->start_regno, mws->end_regno);
       df_print_regset (dump_file, do_not_gen);
       fprintf (dump_file, "  live =");
@@ -3353,6 +3338,11 @@ df_set_dead_notes_for_mw (rtx insn, rtx old, struct df_mw_hardreg *mws,
   if (df_whole_mw_reg_dead_p (mws, live, artificial_uses, do_not_gen))
     {
       /* Add a dead note for the entire multi word register.  */
+      if (is_debug)
+	{
+	  *added_notes_p = true;
+	  return old;
+	}
       old = df_set_note (REG_DEAD, insn, old, mws->mw_reg);
 #ifdef REG_DEAD_DEBUGGING
       df_print_note ("adding 1: ", insn, REG_NOTES (insn));
@@ -3365,6 +3355,11 @@ df_set_dead_notes_for_mw (rtx insn, rtx old, struct df_mw_hardreg *mws,
 	    && !bitmap_bit_p (artificial_uses, r)
 	    && !bitmap_bit_p (do_not_gen, r))
 	  {
+	    if (is_debug)
+	      {
+		*added_notes_p = true;
+		return old;
+	      }
 	    old = df_set_note (REG_DEAD, insn, old, regno_reg_rtx[r]);
 #ifdef REG_DEAD_DEBUGGING
 	    df_print_note ("adding 2: ", insn, REG_NOTES (insn));
@@ -3379,11 +3374,11 @@ df_set_dead_notes_for_mw (rtx insn, rtx old, struct df_mw_hardreg *mws,
    LIVE.  Do not generate notes for registers in ARTIFICIAL_USES.  */
 
 static rtx
-df_create_unused_note (rtx insn, rtx old, df_ref def, 
+df_create_unused_note (rtx insn, rtx old, df_ref def,
 		       bitmap live, bitmap artificial_uses)
 {
   unsigned int dregno = DF_REF_REGNO (def);
-  
+
 #ifdef REG_DEAD_DEBUGGING
   if (dump_file)
     {
@@ -3397,30 +3392,185 @@ df_create_unused_note (rtx insn, rtx old, df_ref def,
 	|| bitmap_bit_p (artificial_uses, dregno)
 	|| df_ignore_stack_reg (dregno)))
     {
-      rtx reg = (DF_REF_LOC (def)) 
+      rtx reg = (DF_REF_LOC (def))
                 ? *DF_REF_REAL_LOC (def): DF_REF_REG (def);
       old = df_set_note (REG_UNUSED, insn, old, reg);
 #ifdef REG_DEAD_DEBUGGING
       df_print_note ("adding 3: ", insn, REG_NOTES (insn));
 #endif
     }
-  
+
   return old;
 }
 
+/* Node of a linked list of uses of dead REGs in debug insns.  */
+struct dead_debug_use
+{
+  df_ref use;
+  struct dead_debug_use *next;
+};
+
+/* Linked list of the above, with a bitmap of the REGs in the
+   list.  */
+struct dead_debug
+{
+  struct dead_debug_use *head;
+  bitmap used;
+  bitmap to_rescan;
+};
+
+/* Initialize DEBUG to an empty list, and clear USED, if given.  */
+static inline void
+dead_debug_init (struct dead_debug *debug, bitmap used)
+{
+  debug->head = NULL;
+  debug->used = used;
+  debug->to_rescan = NULL;
+  if (used)
+    bitmap_clear (used);
+}
+
+/* Reset all debug insns with pending uses.  Release the bitmap in it,
+   unless it is USED.  USED must be the same bitmap passed to
+   dead_debug_init.  */
+static inline void
+dead_debug_finish (struct dead_debug *debug, bitmap used)
+{
+  struct dead_debug_use *head;
+  rtx insn = NULL;
+
+  if (debug->used != used)
+    BITMAP_FREE (debug->used);
+
+  while ((head = debug->head))
+    {
+      insn = DF_REF_INSN (head->use);
+      if (!head->next || DF_REF_INSN (head->next->use) != insn)
+	{
+	  INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
+	  df_insn_rescan_debug_internal (insn);
+	  if (debug->to_rescan)
+	    bitmap_clear_bit (debug->to_rescan, INSN_UID (insn));
+	}
+      debug->head = head->next;
+      XDELETE (head);
+    }
+
+  if (debug->to_rescan)
+    {
+      bitmap_iterator bi;
+      unsigned int uid;
+
+      EXECUTE_IF_SET_IN_BITMAP (debug->to_rescan, 0, uid, bi)
+	{
+	  struct df_insn_info *insn_info = DF_INSN_UID_SAFE_GET (uid);
+	  if (insn_info)
+	    df_insn_rescan (insn_info->insn);
+	}
+      BITMAP_FREE (debug->to_rescan);
+    }
+}
+
+/* Add USE to DEBUG.  It must be a dead reference to UREGNO in a debug
+   insn.  Create a bitmap for DEBUG as needed.  */
+static inline void
+dead_debug_add (struct dead_debug *debug, df_ref use, unsigned int uregno)
+{
+  struct dead_debug_use *newddu = XNEW (struct dead_debug_use);
+
+  newddu->use = use;
+  newddu->next = debug->head;
+  debug->head = newddu;
+
+  if (!debug->used)
+    debug->used = BITMAP_ALLOC (NULL);
+
+  bitmap_set_bit (debug->used, uregno);
+}
+
+/* If UREGNO is referenced by any entry in DEBUG, emit a debug insn
+   before INSN that binds the REG to a debug temp, and replace all
+   uses of UREGNO in DEBUG with uses of the debug temp.  INSN must be
+   the insn where UREGNO dies.  */
+static inline void
+dead_debug_insert_before (struct dead_debug *debug, unsigned int uregno,
+			  rtx insn)
+{
+  struct dead_debug_use **tailp = &debug->head;
+  struct dead_debug_use *cur;
+  struct dead_debug_use *uses = NULL;
+  struct dead_debug_use **usesp = &uses;
+  rtx reg = NULL;
+  rtx dval;
+  rtx bind;
+
+  if (!debug->used || !bitmap_clear_bit (debug->used, uregno))
+    return;
+
+  /* Move all uses of uregno from debug->head to uses, setting mode to
+     the widest referenced mode.  */
+  while ((cur = *tailp))
+    {
+      if (DF_REF_REGNO (cur->use) == uregno)
+	{
+	  *usesp = cur;
+	  usesp = &cur->next;
+	  *tailp = cur->next;
+	  cur->next = NULL;
+	  if (!reg
+	      || (GET_MODE_BITSIZE (GET_MODE (reg))
+		  < GET_MODE_BITSIZE (GET_MODE (*DF_REF_REAL_LOC (cur->use)))))
+	    reg = *DF_REF_REAL_LOC (cur->use);
+	}
+      else
+	tailp = &(*tailp)->next;
+    }
+
+  gcc_assert (reg);
+
+  /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL).  */
+  dval = make_debug_expr_from_rtl (reg);
+
+  /* Emit a debug bind insn before the insn in which reg dies.  */
+  bind = gen_rtx_VAR_LOCATION (GET_MODE (reg),
+			       DEBUG_EXPR_TREE_DECL (dval), reg,
+			       VAR_INIT_STATUS_INITIALIZED);
+
+  bind = emit_debug_insn_before (bind, insn);
+  df_insn_rescan (bind);
+
+  /* Adjust all uses.  */
+  while ((cur = uses))
+    {
+      if (GET_MODE (*DF_REF_REAL_LOC (cur->use)) == GET_MODE (reg))
+	*DF_REF_REAL_LOC (cur->use) = dval;
+      else
+	*DF_REF_REAL_LOC (cur->use)
+	  = gen_lowpart_SUBREG (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval);
+      /* ??? Should we simplify subreg of subreg?  */
+      if (debug->to_rescan == NULL)
+	debug->to_rescan = BITMAP_ALLOC (NULL);
+      bitmap_set_bit (debug->to_rescan, INSN_UID (DF_REF_INSN (cur->use)));
+      uses = cur->next;
+      XDELETE (cur);
+    }
+}
 
 /* Recompute the REG_DEAD and REG_UNUSED notes and compute register
    info: lifetime, bb, and number of defs and uses for basic block
    BB.  The three bitvectors are scratch regs used here.  */
 
 static void
-df_note_bb_compute (unsigned int bb_index, 
+df_note_bb_compute (unsigned int bb_index,
 		    bitmap live, bitmap do_not_gen, bitmap artificial_uses)
 {
   basic_block bb = BASIC_BLOCK (bb_index);
   rtx insn;
   df_ref *def_rec;
   df_ref *use_rec;
+  struct dead_debug debug;
+
+  dead_debug_init (&debug, NULL);
 
   bitmap_copy (live, df_get_live_out (bb));
   bitmap_clear (artificial_uses);
@@ -3454,13 +3604,13 @@ df_note_bb_compute (unsigned int bb_index,
 	{
 	  unsigned int regno = DF_REF_REGNO (use);
 	  bitmap_set_bit (live, regno);
-	  
+
 	  /* Notes are not generated for any of the artificial registers
 	     at the bottom of the block.  */
 	  bitmap_set_bit (artificial_uses, regno);
 	}
     }
-  
+
 #ifdef REG_DEAD_DEBUGGING
   if (dump_file)
     {
@@ -3475,10 +3625,13 @@ df_note_bb_compute (unsigned int bb_index,
       struct df_mw_hardreg **mws_rec;
       rtx old_dead_notes;
       rtx old_unused_notes;
- 
+      int debug_insn;
+
       if (!INSN_P (insn))
 	continue;
 
+      debug_insn = DEBUG_INSN_P (insn);
+
       bitmap_clear (do_not_gen);
       df_kill_notes (insn, &old_dead_notes, &old_unused_notes);
 
@@ -3497,12 +3650,12 @@ df_note_bb_compute (unsigned int bb_index,
 	  mws_rec = DF_INSN_UID_MWS (uid);
 	  while (*mws_rec)
 	    {
-	      struct df_mw_hardreg *mws = *mws_rec; 
-	      if ((DF_MWS_REG_DEF_P (mws)) 
+	      struct df_mw_hardreg *mws = *mws_rec;
+	      if ((DF_MWS_REG_DEF_P (mws))
 		  && !df_ignore_stack_reg (mws->start_regno))
-		old_unused_notes 
-		  = df_set_unused_notes_for_mw (insn, old_unused_notes, 
-						mws, live, do_not_gen, 
+		old_unused_notes
+		  = df_set_unused_notes_for_mw (insn, old_unused_notes,
+						mws, live, do_not_gen,
 						artificial_uses);
 	      mws_rec++;
 	    }
@@ -3516,7 +3669,7 @@ df_note_bb_compute (unsigned int bb_index,
 	      if (!DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER))
 		{
 		  old_unused_notes
-		    = df_create_unused_note (insn, old_unused_notes, 
+		    = df_create_unused_note (insn, old_unused_notes,
 					     def, live, artificial_uses);
 		  bitmap_set_bit (do_not_gen, dregno);
 		}
@@ -3531,11 +3684,11 @@ df_note_bb_compute (unsigned int bb_index,
 	  mws_rec = DF_INSN_UID_MWS (uid);
 	  while (*mws_rec)
 	    {
-	      struct df_mw_hardreg *mws = *mws_rec; 
+	      struct df_mw_hardreg *mws = *mws_rec;
 	      if (DF_MWS_REG_DEF_P (mws))
 		old_unused_notes
-		  = df_set_unused_notes_for_mw (insn, old_unused_notes, 
-						mws, live, do_not_gen, 
+		  = df_set_unused_notes_for_mw (insn, old_unused_notes,
+						mws, live, do_not_gen,
 						artificial_uses);
 	      mws_rec++;
 	    }
@@ -3545,7 +3698,7 @@ df_note_bb_compute (unsigned int bb_index,
 	      df_ref def = *def_rec;
 	      unsigned int dregno = DF_REF_REGNO (def);
 	      old_unused_notes
-		= df_create_unused_note (insn, old_unused_notes, 
+		= df_create_unused_note (insn, old_unused_notes,
 					 def, live, artificial_uses);
 
 	      if (!DF_REF_FLAGS_IS_SET (def, DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER))
@@ -3555,18 +3708,26 @@ df_note_bb_compute (unsigned int bb_index,
 		bitmap_clear_bit (live, dregno);
 	    }
 	}
-      
+
       /* Process the uses.  */
       mws_rec = DF_INSN_UID_MWS (uid);
       while (*mws_rec)
 	{
-	  struct df_mw_hardreg *mws = *mws_rec; 
-	  if ((DF_MWS_REG_DEF_P (mws))  
+	  struct df_mw_hardreg *mws = *mws_rec;
+	  if ((DF_MWS_REG_DEF_P (mws))
 	      && !df_ignore_stack_reg (mws->start_regno))
-	    old_dead_notes
-	      = df_set_dead_notes_for_mw (insn, old_dead_notes, 
-					  mws, live, do_not_gen,
-					  artificial_uses);
+	    {
+	      bool really_add_notes = debug_insn != 0;
+
+	      old_dead_notes
+		= df_set_dead_notes_for_mw (insn, old_dead_notes,
+					    mws, live, do_not_gen,
+					    artificial_uses,
+					    &really_add_notes);
+
+	      if (really_add_notes)
+		debug_insn = -1;
+	    }
 	  mws_rec++;
 	}
 
@@ -3576,7 +3737,7 @@ df_note_bb_compute (unsigned int bb_index,
 	  unsigned int uregno = DF_REF_REGNO (use);
 
 #ifdef REG_DEAD_DEBUGGING
-	  if (dump_file)
+	  if (dump_file && !debug_insn)
 	    {
 	      fprintf (dump_file, "  regular looking at use ");
 	      df_ref_debug (use, dump_file);
@@ -3584,13 +3745,25 @@ df_note_bb_compute (unsigned int bb_index,
 #endif
 	  if (!bitmap_bit_p (live, uregno))
 	    {
+	      if (debug_insn)
+		{
+		  if (debug_insn > 0)
+		    {
+		      dead_debug_add (&debug, use, uregno);
+		      continue;
+		    }
+		  break;
+		}
+	      else
+		dead_debug_insert_before (&debug, uregno, insn);
+
 	      if ( (!(DF_REF_FLAGS (use) & DF_REF_MW_HARDREG))
 		   && (!bitmap_bit_p (do_not_gen, uregno))
 		   && (!bitmap_bit_p (artificial_uses, uregno))
 		   && (!(DF_REF_FLAGS (use) & DF_REF_READ_WRITE))
 		   && (!df_ignore_stack_reg (uregno)))
 		{
-		  rtx reg = (DF_REF_LOC (use)) 
+		  rtx reg = (DF_REF_LOC (use))
                             ? *DF_REF_REAL_LOC (use) : DF_REF_REG (use);
 		  old_dead_notes = df_set_note (REG_DEAD, insn, old_dead_notes, reg);
 
@@ -3615,7 +3788,17 @@ df_note_bb_compute (unsigned int bb_index,
 	  free_EXPR_LIST_node (old_dead_notes);
 	  old_dead_notes = next;
 	}
+
+      if (debug_insn == -1)
+	{
+	  /* ??? We could probably do better here, replacing dead
+	     registers with their definitions.  */
+	  INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC ();
+	  df_insn_rescan_debug_internal (insn);
+	}
     }
+
+  dead_debug_finish (&debug, NULL);
 }
 
 
@@ -3666,8 +3849,8 @@ static struct df_problem problem_NOTE =
   df_note_compute,            /* Local compute function.  */
   NULL,                       /* Init the solution specific data.  */
   NULL,                       /* Iterative solver.  */
-  NULL,                       /* Confluence operator 0.  */ 
-  NULL,                       /* Confluence operator n.  */ 
+  NULL,                       /* Confluence operator 0.  */
+  NULL,                       /* Confluence operator n.  */
   NULL,                       /* Transfer function.  */
   NULL,                       /* Finalize function.  */
   df_note_free,               /* Free all of the problem information.  */
@@ -3697,13 +3880,15 @@ df_note_add_problem (void)
 
 
 /*----------------------------------------------------------------------------
-   Functions for simulating the effects of single insns.  
+   Functions for simulating the effects of single insns.
 
    You can either simulate in the forwards direction, starting from
    the top of a block or the backwards direction from the end of the
-   block.  The main difference is that if you go forwards, the uses
-   are examined first then the defs, and if you go backwards, the defs
-   are examined first then the uses.
+   block.  If you go backwards, defs are examined first to clear bits,
+   then uses are examined to set bits.  If you go forwards, defs are
+   examined first to set bits, then REG_DEAD and REG_UNUSED notes
+   are examined to clear bits.  In either case, the result of examining
+   a def can be undone (respectively by a use or a REG_UNUSED note).
 
    If you start at the top of the block, use one of DF_LIVE_IN or
    DF_LR_IN.  If you start at the bottom of the block use one of
@@ -3723,9 +3908,22 @@ df_simulate_find_defs (rtx insn, bitmap defs)
   for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
     {
       df_ref def = *def_rec;
-      /* If the def is to only part of the reg, it does
-	 not kill the other defs that reach here.  */
-      if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
+      bitmap_set_bit (defs, DF_REF_REGNO (def));
+    }
+}
+
+/* Find the set of real DEFs, which are not clobbers, for INSN.  */
+
+void
+df_simulate_find_noclobber_defs (rtx insn, bitmap defs)
+{
+  df_ref *def_rec;
+  unsigned int uid = INSN_UID (insn);
+
+  for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
+    {
+      df_ref def = *def_rec;
+      if (!(DF_REF_FLAGS (def) & (DF_REF_MUST_CLOBBER | DF_REF_MAY_CLOBBER)))
 	bitmap_set_bit (defs, DF_REF_REGNO (def));
     }
 }
@@ -3749,17 +3947,20 @@ df_simulate_defs (rtx insn, bitmap live)
       if (!(DF_REF_FLAGS (def) & (DF_REF_PARTIAL | DF_REF_CONDITIONAL)))
 	bitmap_clear_bit (live, dregno);
     }
-}  
+}
 
 
 /* Simulate the effects of the uses of INSN on LIVE.  */
 
-void 
+void
 df_simulate_uses (rtx insn, bitmap live)
 {
   df_ref *use_rec;
   unsigned int uid = INSN_UID (insn);
 
+  if (DEBUG_INSN_P (insn))
+    return;
+
   for (use_rec = DF_INSN_UID_USES (uid); *use_rec; use_rec++)
     {
       df_ref use = *use_rec;
@@ -3790,7 +3991,7 @@ df_simulate_fixup_sets (basic_block bb, bitmap live)
    df_simulate_initialize_backwards should be called first with a
    bitvector copyied from the DF_LIVE_OUT or DF_LR_OUT.  Then
    df_simulate_one_insn_backwards should be called for each insn in
-   the block, starting with the last on.  Finally,
+   the block, starting with the last one.  Finally,
    df_simulate_finalize_backwards can be called to get a new value
    of the sets at the top of the block (this is rarely used).
    ----------------------------------------------------------------------------*/
@@ -3798,13 +3999,13 @@ df_simulate_fixup_sets (basic_block bb, bitmap live)
 /* Apply the artificial uses and defs at the end of BB in a backwards
    direction.  */
 
-void 
+void
 df_simulate_initialize_backwards (basic_block bb, bitmap live)
 {
   df_ref *def_rec;
   df_ref *use_rec;
   int bb_index = bb->index;
-  
+
   for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
     {
       df_ref def = *def_rec;
@@ -3823,12 +4024,12 @@ df_simulate_initialize_backwards (basic_block bb, bitmap live)
 
 /* Simulate the backwards effects of INSN on the bitmap LIVE.  */
 
-void 
+void
 df_simulate_one_insn_backwards (basic_block bb, rtx insn, bitmap live)
 {
-  if (! INSN_P (insn))
-    return;	
-  
+  if (!NONDEBUG_INSN_P (insn))
+    return;
+
   df_simulate_defs (insn, live);
   df_simulate_uses (insn, live);
   df_simulate_fixup_sets (bb, live);
@@ -3838,7 +4039,7 @@ df_simulate_one_insn_backwards (basic_block bb, rtx insn, bitmap live)
 /* Apply the artificial uses and defs at the top of BB in a backwards
    direction.  */
 
-void 
+void
 df_simulate_finalize_backwards (basic_block bb, bitmap live)
 {
   df_ref *def_rec;
@@ -3846,7 +4047,7 @@ df_simulate_finalize_backwards (basic_block bb, bitmap live)
   df_ref *use_rec;
 #endif
   int bb_index = bb->index;
-  
+
   for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
     {
       df_ref def = *def_rec;
@@ -3866,47 +4067,51 @@ df_simulate_finalize_backwards (basic_block bb, bitmap live)
 /*----------------------------------------------------------------------------
    The following three functions are used only for FORWARDS scanning:
    i.e. they process the defs and the REG_DEAD and REG_UNUSED notes.
-   Thus it is important to add the DF_NOTES problem to the stack of 
+   Thus it is important to add the DF_NOTES problem to the stack of
    problems computed before using these functions.
 
    df_simulate_initialize_forwards should be called first with a
    bitvector copyied from the DF_LIVE_IN or DF_LR_IN.  Then
    df_simulate_one_insn_forwards should be called for each insn in
-   the block, starting with the last on.  Finally,
-   df_simulate_finalize_forwards can be called to get a new value
-   of the sets at the bottom of the block (this is rarely used).
+   the block, starting with the first one.
    ----------------------------------------------------------------------------*/
 
-/* Apply the artificial uses and defs at the top of BB in a backwards
-   direction.  */
+/* Initialize the LIVE bitmap, which should be copied from DF_LIVE_IN or
+   DF_LR_IN for basic block BB, for forward scanning by marking artificial
+   defs live.  */
 
-void 
+void
 df_simulate_initialize_forwards (basic_block bb, bitmap live)
 {
   df_ref *def_rec;
   int bb_index = bb->index;
-  
+
   for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
     {
       df_ref def = *def_rec;
       if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
-	bitmap_clear_bit (live, DF_REF_REGNO (def));
+	bitmap_set_bit (live, DF_REF_REGNO (def));
     }
 }
 
-/* Simulate the backwards effects of INSN on the bitmap LIVE.  */
+/* Simulate the forwards effects of INSN on the bitmap LIVE.  */
 
-void 
+void
 df_simulate_one_insn_forwards (basic_block bb, rtx insn, bitmap live)
 {
   rtx link;
   if (! INSN_P (insn))
-    return;	
+    return;
 
-  /* Make sure that the DF_NOTES really is an active df problem.  */ 
+  /* Make sure that DF_NOTE really is an active df problem.  */
   gcc_assert (df_note);
 
-  df_simulate_defs (insn, live);
+  /* Note that this is the opposite as how the problem is defined, because
+     in the LR problem defs _kill_ liveness.  However, they do so backwards,
+     while here the scan is performed forwards!  So, first assume that the
+     def is live, and if this is not true REG_UNUSED notes will rectify the
+     situation.  */
+  df_simulate_find_noclobber_defs (insn, live);
 
   /* Clear all of the registers that go dead.  */
   for (link = REG_NOTES (insn); link; link = XEXP (link, 1))
@@ -3924,7 +4129,7 @@ df_simulate_one_insn_forwards (basic_block bb, rtx insn, bitmap live)
 		while (--n >= 0)
 		  bitmap_clear_bit (live, regno + n);
 	      }
-	    else 
+	    else
 	      bitmap_clear_bit (live, regno);
 	  }
 	  break;
@@ -3936,19 +4141,464 @@ df_simulate_one_insn_forwards (basic_block bb, rtx insn, bitmap live)
 }
 
 
-/* Apply the artificial uses and defs at the end of BB in a backwards
-   direction.  */
+
+/*----------------------------------------------------------------------------
+   MULTIPLE DEFINITIONS
+
+   Find the locations in the function reached by multiple definition sites
+   for a live pseudo.  In and out bitvectors are built for each basic
+   block.  They are restricted for efficiency to live registers.
+
+   The gen and kill sets for the problem are obvious.  Together they
+   include all defined registers in a basic block; the gen set includes
+   registers where a partial or conditional or may-clobber definition is
+   last in the BB, while the kill set includes registers with a complete
+   definition coming last.  However, the computation of the dataflow
+   itself is interesting.
+
+   The idea behind it comes from SSA form's iterated dominance frontier
+   criterion for inserting PHI functions.  Just like in that case, we can use
+   the dominance frontier to find places where multiple definitions meet;
+   a register X defined in a basic block BB1 has multiple definitions in
+   basic blocks in BB1's dominance frontier.
+
+   So, the in-set of a basic block BB2 is not just the union of the
+   out-sets of BB2's predecessors, but includes some more bits that come
+   from the basic blocks of whose dominance frontier BB2 is part (BB1 in
+   the previous paragraph).  I called this set the init-set of BB2.
+
+      (Note: I actually use the kill-set only to build the init-set.
+      gen bits are anyway propagated from BB1 to BB2 by dataflow).
+
+    For example, if you have
 
-void 
-df_simulate_finalize_forwards (basic_block bb, bitmap live)
+       BB1 : r10 = 0
+             r11 = 0
+             if <...> goto BB2 else goto BB3;
+
+       BB2 : r10 = 1
+             r12 = 1
+             goto BB3;
+
+       BB3 :
+
+    you have BB3 in BB2's dominance frontier but not in BB1's, so that the
+    init-set of BB3 includes r10 and r12, but not r11.  Note that we do
+    not need to iterate the dominance frontier, because we do not insert
+    anything like PHI functions there!  Instead, dataflow will take care of
+    propagating the information to BB3's successors.
+   ---------------------------------------------------------------------------*/
+
+/* Scratch var used by transfer functions.  This is used to do md analysis
+   only for live registers.  */
+static bitmap df_md_scratch;
+
+/* Set basic block info.  */
+
+static void
+df_md_set_bb_info (unsigned int index,
+                   struct df_md_bb_info *bb_info)
+{
+  gcc_assert (df_md);
+  gcc_assert (index < df_md->block_info_size);
+  df_md->block_info[index] = bb_info;
+}
+
+
+static void
+df_md_free_bb_info (basic_block bb ATTRIBUTE_UNUSED,
+                    void *vbb_info)
+{
+  struct df_md_bb_info *bb_info = (struct df_md_bb_info *) vbb_info;
+  if (bb_info)
+    {
+      BITMAP_FREE (bb_info->kill);
+      BITMAP_FREE (bb_info->gen);
+      BITMAP_FREE (bb_info->init);
+      BITMAP_FREE (bb_info->in);
+      BITMAP_FREE (bb_info->out);
+      pool_free (df_md->block_pool, bb_info);
+    }
+}
+
+
+/* Allocate or reset bitmaps for DF_MD. The solution bits are
+   not touched unless the block is new.  */
+
+static void
+df_md_alloc (bitmap all_blocks)
+{
+  unsigned int bb_index;
+  bitmap_iterator bi;
+
+  if (!df_md->block_pool)
+    df_md->block_pool = create_alloc_pool ("df_md_block pool",
+                                           sizeof (struct df_md_bb_info), 50);
+
+  df_grow_bb_info (df_md);
+  df_md_scratch = BITMAP_ALLOC (NULL);
+
+  EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
+    {
+      struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
+      if (bb_info)
+        {
+          bitmap_clear (bb_info->init);
+          bitmap_clear (bb_info->gen);
+          bitmap_clear (bb_info->kill);
+          bitmap_clear (bb_info->in);
+          bitmap_clear (bb_info->out);
+        }
+      else
+        {
+          bb_info = (struct df_md_bb_info *) pool_alloc (df_md->block_pool);
+          df_md_set_bb_info (bb_index, bb_info);
+          bb_info->init = BITMAP_ALLOC (NULL);
+          bb_info->gen = BITMAP_ALLOC (NULL);
+          bb_info->kill = BITMAP_ALLOC (NULL);
+          bb_info->in = BITMAP_ALLOC (NULL);
+          bb_info->out = BITMAP_ALLOC (NULL);
+        }
+    }
+
+  df_md->optional_p = true;
+}
+
+/* Add the effect of the top artificial defs of BB to the multiple definitions
+   bitmap LOCAL_MD.  */
+
+void
+df_md_simulate_artificial_defs_at_top (basic_block bb, bitmap local_md)
 {
-  df_ref *def_rec;
   int bb_index = bb->index;
-  
+  df_ref *def_rec;
   for (def_rec = df_get_artificial_defs (bb_index); *def_rec; def_rec++)
     {
       df_ref def = *def_rec;
-      if ((DF_REF_FLAGS (def) & DF_REF_AT_TOP) == 0)
-	bitmap_clear_bit (live, DF_REF_REGNO (def));
+      if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
+	{
+	  unsigned int dregno = DF_REF_REGNO (def);
+	  if (DF_REF_FLAGS (def)
+	      & (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))
+	    bitmap_set_bit (local_md, dregno);
+	  else
+	    bitmap_clear_bit (local_md, dregno);
+	}
+    }
+}
+
+
+/* Add the effect of the defs of INSN to the reaching definitions bitmap
+   LOCAL_MD.  */
+
+void
+df_md_simulate_one_insn (basic_block bb ATTRIBUTE_UNUSED, rtx insn,
+                        bitmap local_md)
+{
+  unsigned uid = INSN_UID (insn);
+  df_ref *def_rec;
+
+  for (def_rec = DF_INSN_UID_DEFS (uid); *def_rec; def_rec++)
+    {
+      df_ref def = *def_rec;
+      unsigned int dregno = DF_REF_REGNO (def);
+      if ((!(df->changeable_flags & DF_NO_HARD_REGS))
+          || (dregno >= FIRST_PSEUDO_REGISTER))
+        {
+          if (DF_REF_FLAGS (def)
+	      & (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))
+           bitmap_set_bit (local_md, DF_REF_ID (def));
+         else
+           bitmap_clear_bit (local_md, DF_REF_ID (def));
+        }
+    }
+}
+
+static void
+df_md_bb_local_compute_process_def (struct df_md_bb_info *bb_info,
+                                    df_ref *def_rec,
+                                    int top_flag)
+{
+  df_ref def;
+  bitmap_clear (seen_in_insn);
+
+  while ((def = *def_rec++) != NULL)
+    {
+      unsigned int dregno = DF_REF_REGNO (def);
+      if (((!(df->changeable_flags & DF_NO_HARD_REGS))
+	    || (dregno >= FIRST_PSEUDO_REGISTER))
+	  && top_flag == (DF_REF_FLAGS (def) & DF_REF_AT_TOP))
+	{
+          if (!bitmap_bit_p (seen_in_insn, dregno))
+	    {
+	      if (DF_REF_FLAGS (def)
+	          & (DF_REF_PARTIAL | DF_REF_CONDITIONAL | DF_REF_MAY_CLOBBER))
+	        {
+	          bitmap_set_bit (bb_info->gen, dregno);
+	          bitmap_clear_bit (bb_info->kill, dregno);
+	        }
+	      else
+	        {
+		  /* When we find a clobber and a regular def,
+		     make sure the regular def wins.  */
+	          bitmap_set_bit (seen_in_insn, dregno);
+	          bitmap_set_bit (bb_info->kill, dregno);
+	          bitmap_clear_bit (bb_info->gen, dregno);
+	        }
+	    }
+	}
+    }
+}
+
+
+/* Compute local multiple def info for basic block BB.  */
+
+static void
+df_md_bb_local_compute (unsigned int bb_index)
+{
+  basic_block bb = BASIC_BLOCK (bb_index);
+  struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
+  rtx insn;
+
+  /* Artificials are only hard regs.  */
+  if (!(df->changeable_flags & DF_NO_HARD_REGS))
+    df_md_bb_local_compute_process_def (bb_info,
+                                        df_get_artificial_defs (bb_index),
+                                        DF_REF_AT_TOP);
+
+  FOR_BB_INSNS (bb, insn)
+    {
+      unsigned int uid = INSN_UID (insn);
+      if (!INSN_P (insn))
+        continue;
+
+      df_md_bb_local_compute_process_def (bb_info, DF_INSN_UID_DEFS (uid), 0);
+    }
+
+  if (!(df->changeable_flags & DF_NO_HARD_REGS))
+    df_md_bb_local_compute_process_def (bb_info,
+                                        df_get_artificial_defs (bb_index),
+                                        0);
+}
+
+/* Compute local reaching def info for each basic block within BLOCKS.  */
+
+static void
+df_md_local_compute (bitmap all_blocks)
+{
+  unsigned int bb_index, df_bb_index;
+  bitmap_iterator bi1, bi2;
+  basic_block bb;
+  bitmap *frontiers;
+
+  seen_in_insn = BITMAP_ALLOC (NULL);
+
+  EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi1)
+    {
+      df_md_bb_local_compute (bb_index);
+    }
+
+  BITMAP_FREE (seen_in_insn);
+
+  frontiers = XNEWVEC (bitmap, last_basic_block);
+  FOR_ALL_BB (bb)
+    frontiers[bb->index] = BITMAP_ALLOC (NULL);
+
+  compute_dominance_frontiers (frontiers);
+
+  /* Add each basic block's kills to the nodes in the frontier of the BB.  */
+  EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi1)
+    {
+      bitmap kill = df_md_get_bb_info (bb_index)->kill;
+      EXECUTE_IF_SET_IN_BITMAP (frontiers[bb_index], 0, df_bb_index, bi2)
+	{
+	  basic_block bb = BASIC_BLOCK (df_bb_index);
+	  if (bitmap_bit_p (all_blocks, df_bb_index))
+	    bitmap_ior_and_into (df_md_get_bb_info (df_bb_index)->init, kill,
+				 df_get_live_in (bb));
+	}
+    }
+
+  FOR_ALL_BB (bb)
+    BITMAP_FREE (frontiers[bb->index]);
+  free (frontiers);
+}
+
+
+/* Reset the global solution for recalculation.  */
+
+static void
+df_md_reset (bitmap all_blocks)
+{
+  unsigned int bb_index;
+  bitmap_iterator bi;
+
+  EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
+    {
+      struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
+      gcc_assert (bb_info);
+      bitmap_clear (bb_info->in);
+      bitmap_clear (bb_info->out);
+    }
+}
+
+static bool
+df_md_transfer_function (int bb_index)
+{
+  basic_block bb = BASIC_BLOCK (bb_index);
+  struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
+  bitmap in = bb_info->in;
+  bitmap out = bb_info->out;
+  bitmap gen = bb_info->gen;
+  bitmap kill = bb_info->kill;
+
+  /* We need to use a scratch set here so that the value returned from this
+     function invocation properly reflects whether the sets changed in a
+     significant way; i.e. not just because the live set was anded in.  */
+  bitmap_and (df_md_scratch, gen, df_get_live_out (bb));
+
+  /* Multiple definitions of a register are not relevant if it is not
+     live.  Thus we trim the result to the places where it is live.  */
+  bitmap_and_into (in, df_get_live_in (bb));
+
+  return bitmap_ior_and_compl (out, df_md_scratch, in, kill);
+}
+
+/* Initialize the solution bit vectors for problem.  */
+
+static void
+df_md_init (bitmap all_blocks)
+{
+  unsigned int bb_index;
+  bitmap_iterator bi;
+
+  EXECUTE_IF_SET_IN_BITMAP (all_blocks, 0, bb_index, bi)
+    {
+      struct df_md_bb_info *bb_info = df_md_get_bb_info (bb_index);
+
+      bitmap_copy (bb_info->in, bb_info->init);
+      df_md_transfer_function (bb_index);
+    }
+}
+
+static void
+df_md_confluence_0 (basic_block bb)
+{
+  struct df_md_bb_info *bb_info = df_md_get_bb_info (bb->index);
+  bitmap_copy (bb_info->in, bb_info->init);
+}
+
+/* In of target gets or of out of source.  */
+
+static void
+df_md_confluence_n (edge e)
+{
+  bitmap op1 = df_md_get_bb_info (e->dest->index)->in;
+  bitmap op2 = df_md_get_bb_info (e->src->index)->out;
+
+  if (e->flags & EDGE_FAKE)
+    return;
+
+  if (e->flags & EDGE_EH)
+    bitmap_ior_and_compl_into (op1, op2, regs_invalidated_by_call_regset);
+  else
+    bitmap_ior_into (op1, op2);
+}
+
+/* Free all storage associated with the problem.  */
+
+static void
+df_md_free (void)
+{
+  unsigned int i;
+  for (i = 0; i < df_md->block_info_size; i++)
+    {
+      struct df_md_bb_info *bb_info = df_md_get_bb_info (i);
+      if (bb_info)
+	{
+	  BITMAP_FREE (bb_info->kill);
+	  BITMAP_FREE (bb_info->gen);
+	  BITMAP_FREE (bb_info->init);
+	  BITMAP_FREE (bb_info->in);
+	  BITMAP_FREE (bb_info->out);
+	}
     }
+
+  BITMAP_FREE (df_md_scratch);
+  free_alloc_pool (df_md->block_pool);
+
+  df_md->block_info_size = 0;
+  free (df_md->block_info);
+  free (df_md);
+}
+
+
+/* Debugging info at top of bb.  */
+
+static void
+df_md_top_dump (basic_block bb, FILE *file)
+{
+  struct df_md_bb_info *bb_info = df_md_get_bb_info (bb->index);
+  if (!bb_info || !bb_info->in)
+    return;
+
+  fprintf (file, ";; md  in  \t");
+  df_print_regset (file, bb_info->in);
+  fprintf (file, ";; md  init  \t");
+  df_print_regset (file, bb_info->init);
+  fprintf (file, ";; md  gen \t");
+  df_print_regset (file, bb_info->gen);
+  fprintf (file, ";; md  kill \t");
+  df_print_regset (file, bb_info->kill);
+}
+
+/* Debugging info at bottom of bb.  */
+
+static void
+df_md_bottom_dump (basic_block bb, FILE *file)
+{
+  struct df_md_bb_info *bb_info = df_md_get_bb_info (bb->index);
+  if (!bb_info || !bb_info->out)
+    return;
+
+  fprintf (file, ";; md  out \t");
+  df_print_regset (file, bb_info->out);
+}
+
+static struct df_problem problem_MD =
+{
+  DF_MD,                      /* Problem id.  */
+  DF_FORWARD,                 /* Direction.  */
+  df_md_alloc,                /* Allocate the problem specific data.  */
+  df_md_reset,                /* Reset global information.  */
+  df_md_free_bb_info,         /* Free basic block info.  */
+  df_md_local_compute,        /* Local compute function.  */
+  df_md_init,                 /* Init the solution specific data.  */
+  df_worklist_dataflow,       /* Worklist solver.  */
+  df_md_confluence_0,         /* Confluence operator 0.  */
+  df_md_confluence_n,         /* Confluence operator n.  */
+  df_md_transfer_function,    /* Transfer function.  */
+  NULL,                       /* Finalize function.  */
+  df_md_free,                 /* Free all of the problem information.  */
+  df_md_free,                 /* Remove this problem from the stack of dataflow problems.  */
+  NULL,                       /* Debugging.  */
+  df_md_top_dump,             /* Debugging start block.  */
+  df_md_bottom_dump,          /* Debugging end block.  */
+  NULL,			      /* Incremental solution verify start.  */
+  NULL,			      /* Incremental solution verify end.  */
+  NULL,                       /* Dependent problem.  */
+  TV_DF_MD,                   /* Timing variable.  */
+  false                       /* Reset blocks on dropping out of blocks_to_analyze.  */
+};
+
+/* Create a new MD instance and add it to the existing instance
+   of DF.  */
+
+void
+df_md_add_problem (void)
+{
+  df_add_problem (&problem_MD);
 }
+
+
+