cfglayout.c (cfg_layout_duplicate_bb): Do not update frequencies at all if edge is not specified.

	* cfglayout.c (cfg_layout_duplicate_bb): Do not update frequencies
	at all if edge is not specified.
	(can_copy_bbs_p, copy_bbs): New.
	* cfglayout.h (can_copy_bbs_p, copy_bbs): Declare.
	* cfgloop.c (get_loop_body): Comment more precisely.
	* cfgloopmanip.c (copy_bbs, record_exit_edges): Removed.
	(scale_bbs_frequencies): Fix comment typo.
	(can_duplicate_loop_p): Use can_copy_bbs_p.
	(duplicate_loop_to_header_edge): Simplify by using copy_bbs.

From-SVN: r68906

1 files changed, 142 insertions, 14 deletions

diff --git a/gcc/cfglayout.c b/gcc/cfglayout.c
index a576f0e..3a6b925 100644
--- a/gcc/cfglayout.c
+++ b/gcc/cfglayout.c
@@ -985,7 +985,9 @@ duplicate_insn_chain (rtx from, rtx to)
   delete_insn (last);
   return insn;
 }
-/* Create a duplicate of the basic block BB and redirect edge E into it.  */
+/* Create a duplicate of the basic block BB and redirect edge E into it.
+   If E is not specified, BB is just copied, but updating the frequencies
+   etc. is left to the caller.  */
 
 basic_block
 cfg_layout_duplicate_bb (basic_block bb, edge e)
@@ -1046,32 +1048,41 @@ cfg_layout_duplicate_bb (basic_block bb, edge e)
 	 is no need to actually check for duplicated edges.  */
       n = unchecked_make_edge (new_bb, s->dest, s->flags);
       n->probability = s->probability;
-      if (new_count)
-	/* Take care for overflows!  */
-	n->count = s->count * (new_count * 10000 / bb->count) / 10000;
+      if (e && bb->count)
+	{
+	  /* Take care for overflows!  */
+	  n->count = s->count * (new_count * 10000 / bb->count) / 10000;
+	  s->count -= n->count;
+	}
       else
-	n->count = 0;
-      s->count -= n->count;
+	n->count = s->count;
+      n->aux = s->aux;
     }
 
-  new_bb->count = new_count;
-  bb->count -= new_count;
-
   if (e)
     {
+      new_bb->count = new_count;
+      bb->count -= new_count;
+
       new_bb->frequency = EDGE_FREQUENCY (e);
       bb->frequency -= EDGE_FREQUENCY (e);
 
       redirect_edge_and_branch_force (e, new_bb);
-    }
 
-  if (bb->count < 0)
-    bb->count = 0;
-  if (bb->frequency < 0)
-    bb->frequency = 0;
+      if (bb->count < 0)
+	bb->count = 0;
+      if (bb->frequency < 0)
+	bb->frequency = 0;
+    }
+  else
+    {
+      new_bb->count = bb->count;
+      new_bb->frequency = bb->frequency;
+    }
 
   new_bb->rbi->original = bb;
   bb->rbi->copy = new_bb;
+
   return new_bb;
 }
 
@@ -1167,4 +1178,121 @@ cfg_layout_finalize (void)
 #endif
 }
 
+/* Checks whether all N blocks in BBS array can be copied.  */
+bool
+can_copy_bbs_p (basic_block *bbs, unsigned n)
+{
+  unsigned i;
+  edge e;
+  int ret = true;
+
+  for (i = 0; i < n; i++)
+    bbs[i]->rbi->duplicated = 1;
+
+  for (i = 0; i < n; i++)
+    {
+      /* In case we should redirect abnormal edge during duplication, fail.  */
+      for (e = bbs[i]->succ; e; e = e->succ_next)
+	if ((e->flags & EDGE_ABNORMAL)
+	    && e->dest->rbi->duplicated)
+	  {
+	    ret = false;
+	    goto end;
+	  }
+
+      if (!cfg_layout_can_duplicate_bb_p (bbs[i]))
+	{
+	  ret = false;
+	  break;
+	}
+    }
+
+end:
+  for (i = 0; i < n; i++)
+    bbs[i]->rbi->duplicated = 0;
+
+  return ret;
+}
+
+/* Duplicates N basic blocks stored in array BBS.  Newly created basic blocks
+   are placed into array NEW_BBS in the same order.  Edges from basic blocks
+   in BBS are also duplicated and copies of those of them
+   that lead into BBS are redirected to appropriate newly created block.  The
+   function assigns bbs into loops (copy of basic block bb is assigned to
+   bb->loop_father->copy loop, so this must be set up correctly in advance)
+   and updates dominators locally (LOOPS structure that contains the information
+   about dominators is passed to enable this).
+
+   BASE is the superloop to that basic block belongs; if its header or latch
+   is copied, we do not set the new blocks as header or latch.
+
+   Created copies of N_EDGES edges in array EDGES are stored in array NEW_EDGES,
+   also in the same order.  */
+
+void
+copy_bbs (basic_block *bbs, unsigned n, basic_block *new_bbs,
+	  edge *edges, unsigned n_edges, edge *new_edges,
+	  struct loop *base, struct loops *loops)
+{
+  unsigned i, j;
+  basic_block bb, new_bb, dom_bb;
+  edge e;
+
+  /* Duplicate bbs, update dominators, assign bbs to loops.  */
+  for (i = 0; i < n; i++)
+    {
+      /* Duplicate.  */
+      bb = bbs[i];
+      new_bb = new_bbs[i] = cfg_layout_duplicate_bb (bb, NULL);
+      bb->rbi->duplicated = 1;
+      /* Add to loop.  */
+      add_bb_to_loop (new_bb, bb->loop_father->copy);
+      add_to_dominance_info (loops->cfg.dom, new_bb);
+      /* Possibly set header.  */
+      if (bb->loop_father->header == bb && bb->loop_father != base)
+	new_bb->loop_father->header = new_bb;
+      /* Or latch.  */
+      if (bb->loop_father->latch == bb && bb->loop_father != base)
+	new_bb->loop_father->latch = new_bb;
+    }
+
+  /* Set dominators.  */
+  for (i = 0; i < n; i++)
+    {
+      bb = bbs[i];
+      new_bb = new_bbs[i];
+
+      dom_bb = get_immediate_dominator (loops->cfg.dom, bb);
+      if (dom_bb->rbi->duplicated)
+	{
+	  dom_bb = dom_bb->rbi->copy;
+	  set_immediate_dominator (loops->cfg.dom, new_bb, dom_bb);
+	}
+    }
+
+  /* Redirect edges.  */
+  for (j = 0; j < n_edges; j++)
+    new_edges[j] = NULL;
+  for (i = 0; i < n; i++)
+    {
+      new_bb = new_bbs[i];
+      bb = bbs[i];
+
+      for (e = new_bb->succ; e; e = e->succ_next)
+	{
+	  for (j = 0; j < n_edges; j++)
+	    if (edges[j] && edges[j]->src == bb && edges[j]->dest == e->dest)
+	      new_edges[j] = e;
+
+	  if (!e->dest->rbi->duplicated)
+	    continue;
+	  redirect_edge_and_branch_force (e, e->dest->rbi->copy);
+	}
+    }
+
+  /* Clear information about duplicates.  */
+  for (i = 0; i < n; i++)
+    bbs[i]->rbi->duplicated = 0;
+}
+
 #include "gt-cfglayout.h"