1 files changed, 14 insertions, 228 deletions

diff --git a/gcc/cfgloop.c b/gcc/cfgloop.c
index 40a6de4..96175a8 100644
--- a/gcc/cfgloop.c
+++ b/gcc/cfgloop.c
@@ -41,11 +41,7 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 #define LATCH_EDGE(E) (*(int *) (E)->aux)
 
 static void flow_loops_cfg_dump (const struct loops *, FILE *);
-static void flow_loop_entry_edges_find (struct loop *);
-static void flow_loop_exit_edges_find (struct loop *);
 static int flow_loop_nodes_find (basic_block, struct loop *);
-static void flow_loop_pre_header_scan (struct loop *);
-static basic_block flow_loop_pre_header_find (basic_block);
 static int flow_loop_level_compute (struct loop *);
 static void flow_loops_level_compute (struct loops *);
 static void establish_preds (struct loop *);
@@ -135,27 +131,18 @@ flow_loop_dump (const struct loop *loop, FILE *file,
   fprintf (file, ";;\n;; Loop %d:%s\n", loop->num,
 	     loop->invalid ? " invalid" : "");
 
-  fprintf (file, ";;  header %d, latch %d, pre-header %d\n",
-	   loop->header->index, loop->latch->index,
-	   loop->pre_header ? loop->pre_header->index : -1);
+  fprintf (file, ";;  header %d, latch %d\n",
+	   loop->header->index, loop->latch->index);
   fprintf (file, ";;  depth %d, level %d, outer %ld\n",
 	   loop->depth, loop->level,
 	   (long) (loop->outer ? loop->outer->num : -1));
 
-  if (loop->pre_header_edges)
-    flow_edge_list_print (";;  pre-header edges", loop->pre_header_edges,
-			  loop->num_pre_header_edges, file);
-
-  flow_edge_list_print (";;  entry edges", loop->entry_edges,
-			loop->num_entries, file);
   fprintf (file, ";;  nodes:");
   bbs = get_loop_body (loop);
   for (i = 0; i < loop->num_nodes; i++)
     fprintf (file, " %d", bbs[i]->index);
   free (bbs);
   fprintf (file, "\n");
-  flow_edge_list_print (";;  exit edges", loop->exit_edges,
-			loop->num_exits, file);
 
   if (loop_dump_aux)
     loop_dump_aux (loop, file, verbose);
@@ -194,12 +181,6 @@ flow_loops_dump (const struct loops *loops, FILE *file, void (*loop_dump_aux) (c
 void
 flow_loop_free (struct loop *loop)
 {
-  if (loop->pre_header_edges)
-    free (loop->pre_header_edges);
-  if (loop->entry_edges)
-    free (loop->entry_edges);
-  if (loop->exit_edges)
-    free (loop->exit_edges);
   if (loop->pred)
     free (loop->pred);
   free (loop);
@@ -238,95 +219,6 @@ flow_loops_free (struct loops *loops)
     }
 }
 
-/* Find the entry edges into the LOOP.  */
-
-static void
-flow_loop_entry_edges_find (struct loop *loop)
-{
-  edge e;
-  edge_iterator ei;
-  int num_entries;
-
-  num_entries = 0;
-  FOR_EACH_EDGE (e, ei, loop->header->preds)
-    {
-      if (flow_loop_outside_edge_p (loop, e))
-	num_entries++;
-    }
-
-  gcc_assert (num_entries);
-
-  loop->entry_edges = xmalloc (num_entries * sizeof (edge *));
-
-  num_entries = 0;
-  FOR_EACH_EDGE (e, ei, loop->header->preds)
-    {
-      if (flow_loop_outside_edge_p (loop, e))
-	loop->entry_edges[num_entries++] = e;
-    }
-
-  loop->num_entries = num_entries;
-}
-
-/* Find the exit edges from the LOOP.  */
-
-static void
-flow_loop_exit_edges_find (struct loop *loop)
-{
-  edge e;
-  basic_block node, *bbs;
-  unsigned num_exits, i;
-
-  loop->exit_edges = NULL;
-  loop->num_exits = 0;
-
-  /* Check all nodes within the loop to see if there are any
-     successors not in the loop.  Note that a node may have multiple
-     exiting edges.  */
-  num_exits = 0;
-  bbs = get_loop_body (loop);
-  for (i = 0; i < loop->num_nodes; i++)
-    {
-      edge_iterator ei;
-      node = bbs[i];
-      FOR_EACH_EDGE (e, ei, node->succs)
-	{
-	  basic_block dest = e->dest;
-
-	  if (!flow_bb_inside_loop_p (loop, dest))
-	    num_exits++;
-	}
-    }
-
-  if (! num_exits)
-    {
-      free (bbs);
-      return;
-    }
-
-  loop->exit_edges = xmalloc (num_exits * sizeof (edge *));
-
-  /* Store all exiting edges into an array.  */
-  num_exits = 0;
-  for (i = 0; i < loop->num_nodes; i++)
-    {
-      edge_iterator ei;
-      node = bbs[i];
-      FOR_EACH_EDGE (e, ei, node->succs)
-	{
-	  basic_block dest = e->dest;
-
-	  if (!flow_bb_inside_loop_p (loop, dest))
-	    {
-	      e->flags |= EDGE_LOOP_EXIT;
-	      loop->exit_edges[num_exits++] = e;
-	    }
-      }
-    }
-  free (bbs);
-  loop->num_exits = num_exits;
-}
-
 /* Find the nodes contained within the LOOP with header HEADER.
    Return the number of nodes within the loop.  */
 
@@ -434,77 +326,6 @@ mark_single_exit_loops (struct loops *loops)
   loops->state |= LOOPS_HAVE_MARKED_SINGLE_EXITS;
 }
 
-/* Find the root node of the loop pre-header extended basic block and
-   the edges along the trace from the root node to the loop header.  */
-
-static void
-flow_loop_pre_header_scan (struct loop *loop)
-{
-  int num;
-  basic_block ebb;
-  edge e;
-
-  loop->num_pre_header_edges = 0;
-  if (loop->num_entries != 1)
-    return;
-
-  ebb = loop->entry_edges[0]->src;
-  if (ebb == ENTRY_BLOCK_PTR)
-    return;
-
-  /* Count number of edges along trace from loop header to
-     root of pre-header extended basic block.  Usually this is
-     only one or two edges.  */
-  for (num = 1;
-       EDGE_PRED (ebb, 0)->src != ENTRY_BLOCK_PTR && EDGE_COUNT (ebb->preds) == 1;
-       num++)
-    ebb = EDGE_PRED (ebb, 0)->src;
-
-  loop->pre_header_edges = xmalloc (num * sizeof (edge));
-  loop->num_pre_header_edges = num;
-
-  /* Store edges in order that they are followed.  The source of the first edge
-     is the root node of the pre-header extended basic block and the
-     destination of the last last edge is the loop header.  */
-  for (e = loop->entry_edges[0]; num; e = EDGE_PRED (e->src, 0))
-    loop->pre_header_edges[--num] = e;
-}
-
-/* Return the block for the pre-header of the loop with header
-   HEADER.  Return NULL if there is no pre-header.  */
-
-static basic_block
-flow_loop_pre_header_find (basic_block header)
-{
-  basic_block pre_header;
-  edge e;
-  edge_iterator ei;
-
-  /* If block p is a predecessor of the header and is the only block
-     that the header does not dominate, then it is the pre-header.  */
-  pre_header = NULL;
-  FOR_EACH_EDGE (e, ei, header->preds)
-    {
-      basic_block node = e->src;
-
-      if (node != ENTRY_BLOCK_PTR
-	  && ! dominated_by_p (CDI_DOMINATORS, node, header))
-	{
-	  if (pre_header == NULL)
-	    pre_header = node;
-	  else
-	    {
-	      /* There are multiple edges into the header from outside
-		 the loop so there is no pre-header block.  */
-	      pre_header = NULL;
-	      break;
-	    }
-	}
-    }
-
-  return pre_header;
-}
-
 static void
 establish_preds (struct loop *loop)
 {
@@ -602,39 +423,6 @@ flow_loops_level_compute (struct loops *loops)
   flow_loop_level_compute (loops->tree_root);
 }
 
-/* Scan a single natural loop specified by LOOP collecting information
-   about it specified by FLAGS.  */
-
-int
-flow_loop_scan (struct loop *loop, int flags)
-{
-  if (flags & LOOP_ENTRY_EDGES)
-    {
-      /* Find edges which enter the loop header.
-	 Note that the entry edges should only
-	 enter the header of a natural loop.  */
-      flow_loop_entry_edges_find (loop);
-    }
-
-  if (flags & LOOP_EXIT_EDGES)
-    {
-      /* Find edges which exit the loop.  */
-      flow_loop_exit_edges_find (loop);
-    }
-
-  if (flags & LOOP_PRE_HEADER)
-    {
-      /* Look to see if the loop has a pre-header node.  */
-      loop->pre_header = flow_loop_pre_header_find (loop->header);
-
-      /* Find the blocks within the extended basic block of
-	 the loop pre-header.  */
-      flow_loop_pre_header_scan (loop);
-    }
-
-  return 1;
-}
-
 /* A callback to update latch and header info for basic block JUMP created
    by redirecting an edge.  */
 
@@ -800,14 +588,12 @@ initialize_loops_parallel_p (struct loops *loops)
 }
 
 /* Find all the natural loops in the function and save in LOOPS structure and
-   recalculate loop_depth information in basic block structures.  FLAGS
-   controls which loop information is collected.  Return the number of natural
-   loops found.  */
+   recalculate loop_depth information in basic block structures.
+   Return the number of natural loops found.  */
 
 int
-flow_loops_find (struct loops *loops, int flags)
+flow_loops_find (struct loops *loops)
 {
-  int i;
   int b;
   int num_loops;
   edge e;
@@ -817,11 +603,6 @@ flow_loops_find (struct loops *loops, int flags)
   basic_block header;
   basic_block bb;
 
-  /* This function cannot be repeatedly called with different
-     flags to build up the loop information.  The loop tree
-     must always be built if this function is called.  */
-  gcc_assert (flags & LOOP_TREE);
-
   memset (loops, 0, sizeof *loops);
 
   /* We are going to recount the maximum loop depth,
@@ -963,10 +744,6 @@ flow_loops_find (struct loops *loops, int flags)
 	 loop.  */
       flow_loops_level_compute (loops);
 
-      /* Scan the loops.  */
-      for (i = 1; i < num_loops; i++)
-	flow_loop_scan (loops->parray[i], flags);
-
       loops->num = num_loops;
       initialize_loops_parallel_p (loops);
     }
@@ -1523,3 +1300,12 @@ loop_preheader_edge (const struct loop *loop)
 
   return e;
 }
+
+/* Returns true if E is an exit of LOOP.  */
+
+bool
+loop_exit_edge_p (const struct loop *loop, edge e)
+{
+  return (flow_bb_inside_loop_p (loop, e->src)
+	  && !flow_bb_inside_loop_p (loop, e->dest));
+}