* configure.ac: Add moxie support.

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-copy.c

diff --git a/gcc/tree-ssa-copy.c b/gcc/tree-ssa-copy.c
index a02aee0..f582ed0 100644 (file)
--- a/gcc/tree-ssa-copy.c
+++ b/gcc/tree-ssa-copy.c
@@ -37,6 +37,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-pass.h"
 #include "tree-ssa-propagate.h"
 #include "langhooks.h"
+#include "cfgloop.h"
 
 /* This file implements the copy propagation pass and provides a
    handful of interfaces for performing const/copy propagation and
@@ -885,7 +886,13 @@ init_copy_prop (void)
           tree def;
 
          def = gimple_phi_result (phi);
-         if (!is_gimple_reg (def))
+         if (!is_gimple_reg (def)
+             /* In loop-closed SSA form do not copy-propagate through
+                PHI nodes.  Technically this is only needed for loop
+                exit PHIs, but this is difficult to query.  */
+             || (current_loops
+                 && gimple_phi_num_args (phi) == 1
+                 && loops_state_satisfies_p (LOOP_CLOSED_SSA)))
             prop_set_simulate_again (phi, false);
          else
             prop_set_simulate_again (phi, true);