* tree-ssa-reassoc.c (repropagate_negates): Merge negates also

[pf3gnuchains/gcc-fork.git] / gcc / tree-cfgcleanup.c

diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c
index eae0c84..723bfc1 100644 (file)
--- a/gcc/tree-cfgcleanup.c
+++ b/gcc/tree-cfgcleanup.c
@@ -1,5 +1,5 @@
 /* CFG cleanup for trees.
-   Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+   Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -103,20 +103,28 @@ cleanup_control_expr_graph (basic_block bb, gimple_stmt_iterator gsi)
            /* For conditions try harder and lookup single-argument
               PHI nodes.  Only do so from the same basic-block though
               as other basic-blocks may be dead already.  */
-           if (TREE_CODE (lhs) == SSA_NAME)
+           if (TREE_CODE (lhs) == SSA_NAME
+               && !name_registered_for_update_p (lhs))
              {
                gimple def_stmt = SSA_NAME_DEF_STMT (lhs);
                if (gimple_code (def_stmt) == GIMPLE_PHI
                    && gimple_phi_num_args (def_stmt) == 1
-                   && gimple_bb (def_stmt) == gimple_bb (stmt))
+                   && gimple_bb (def_stmt) == gimple_bb (stmt)
+                   && (TREE_CODE (PHI_ARG_DEF (def_stmt, 0)) != SSA_NAME
+                       || !name_registered_for_update_p (PHI_ARG_DEF (def_stmt,
+                                                                      0))))
                  lhs = PHI_ARG_DEF (def_stmt, 0);
              }
-           if (TREE_CODE (rhs) == SSA_NAME)
+           if (TREE_CODE (rhs) == SSA_NAME
+               && !name_registered_for_update_p (rhs))
              {
                gimple def_stmt = SSA_NAME_DEF_STMT (rhs);
                if (gimple_code (def_stmt) == GIMPLE_PHI
                    && gimple_phi_num_args (def_stmt) == 1
-                   && gimple_bb (def_stmt) == gimple_bb (stmt))
+                   && gimple_bb (def_stmt) == gimple_bb (stmt)
+                   && (TREE_CODE (PHI_ARG_DEF (def_stmt, 0)) != SSA_NAME
+                       || !name_registered_for_update_p (PHI_ARG_DEF (def_stmt,
+                                                                      0))))
                  rhs = PHI_ARG_DEF (def_stmt, 0);
              }
            val = fold_binary_loc (loc, gimple_cond_code (stmt),