tree-ssa-sink.c (sink_code_in_bb): Don't stop sinking after sinking the last stmt in a BB.

* tree-ssa-sink.c (sink_code_in_bb): Don't stop sinking after
sinking the last stmt in a BB.

From-SVN: r128913

gcc/ChangeLog

 2007-10-01  Alexandre Oliva  <aoliva@redhat.com>
 
+	* tree-ssa-sink.c (sink_code_in_bb): Don't stop sinking after
+	sinking the last stmt in a BB.
+
+2007-10-01  Alexandre Oliva  <aoliva@redhat.com>
+
 	PR middle-end/22156
 	* tree-sra.c (struct sra_elt): Add in_bitfld_block.
 	(sra_hash_tree): Handle BIT_FIELD_REFs.

gcc/tree-ssa-sink.c

@@ -433,6 +433,7 @@ sink_code_in_bb (basic_block bb)
   block_stmt_iterator bsi;
   edge_iterator ei;
   edge e;
+  bool last = true;
   
   /* If this block doesn't dominate anything, there can't be any place to sink
      the statements to.  */
@@ -454,6 +455,7 @@ sink_code_in_bb (basic_block bb)
 	{
 	  if (!bsi_end_p (bsi))
 	    bsi_prev (&bsi);
+	  last = false;
 	  continue;
 	}      
       if (dump_file)
@@ -472,6 +474,19 @@ sink_code_in_bb (basic_block bb)
 	bsi_move_before (&bsi, &tobsi);
 
       sink_stats.sunk++;
+
+      /* If we've just removed the last statement of the BB, the
+	 bsi_end_p() test below would fail, but bsi_prev() would have
+	 succeeded, and we want it to succeed.  So we keep track of
+	 whether we're at the last statement and pick up the new last
+	 statement.  */
+      if (last)
+	{
+	  bsi = bsi_last (bb);
+	  continue;
+	}
+
+      last = false;
       if (!bsi_end_p (bsi))
 	bsi_prev (&bsi);