PR tree-optimization/65735
        * tree-ssa-threadedge.c (fsm_find_control_statement_thread_paths):
        Remove visited_phis argument, add visited_bbs, avoid recursing into the
        same bb rather than just into the same phi node.
        (thread_through_normal_block): Adjust caller.

        * gcc.c-torture/compile/pr65735.c: New test.
---
 .../gcc/testsuite/gcc.c-torture/compile/pr65735.c   | 21 +++++++++++++++++++++
 gcc-4.9/gcc/tree-ssa-threadedge.c                   | 12 ++++++------
 2 files changed, 27 insertions(+), 6 deletions(-)
 create mode 100644 gcc-4.9/gcc/testsuite/gcc.c-torture/compile/pr65735.c

diff --git a/gcc-4.9/gcc/testsuite/gcc.c-torture/compile/pr65735.c 
b/gcc-4.9/gcc/testsuite/gcc.c-torture/compile/pr65735.c
new file mode 100644
index 0000000..c30de8e
--- /dev/null
+++ b/gcc-4.9/gcc/testsuite/gcc.c-torture/compile/pr65735.c
@@ -0,0 +1,21 @@
+/* PR tree-optimization/65735 */
+
+int foo (void);
+
+void
+bar (int a, int b, int c)
+{
+  while (!a)
+    {
+      c = foo ();
+      if (c == 7)
+       c = b;
+      switch (c)
+       {
+       case 1:
+         a = b++;
+         if (b)
+           b = 1;
+       }
+    }
+}
diff --git a/gcc-4.9/gcc/tree-ssa-threadedge.c 
b/gcc-4.9/gcc/tree-ssa-threadedge.c
index cad91ef..604123e 100644
--- a/gcc-4.9/gcc/tree-ssa-threadedge.c
+++ b/gcc-4.9/gcc/tree-ssa-threadedge.c
@@ -947,7 +947,7 @@ static int max_threaded_paths;
 
 static void
 fsm_find_control_statement_thread_paths (tree expr,
-                                        pointer_set_t *visited_phis,
+                                        pointer_set_t *visited_bbs,
                                         vec<basic_block, va_gc> *&path,
                                         bool seen_loop_phi)
 {
@@ -966,7 +966,7 @@ fsm_find_control_statement_thread_paths (tree expr,
     return;
 
   /* Avoid infinite recursion.  */
-  if (pointer_set_insert (visited_phis, def_stmt))
+  if (pointer_set_insert (visited_bbs, var_bb))
     return;
 
   int next_path_length = 0;
@@ -1040,7 +1040,7 @@ fsm_find_control_statement_thread_paths (tree expr,
        {
          vec_safe_push (path, bbi);
          /* Recursively follow SSA_NAMEs looking for a constant definition.  */
-         fsm_find_control_statement_thread_paths (arg, visited_phis, path,
+         fsm_find_control_statement_thread_paths (arg, visited_bbs, path,
                                                   seen_loop_phi);
 
          path->pop ();
@@ -1306,13 +1306,13 @@ thread_through_normal_block (edge e,
       vec<basic_block, va_gc> *bb_path;
       vec_alloc (bb_path, n_basic_blocks_for_fn (cfun));
       vec_safe_push (bb_path, e->dest);
-      pointer_set_t *visited_phis = pointer_set_create ();
+      pointer_set_t *visited_bbs = pointer_set_create ();
 
       max_threaded_paths = PARAM_VALUE (PARAM_MAX_FSM_THREAD_PATHS);
-      fsm_find_control_statement_thread_paths (cond, visited_phis, bb_path,
+      fsm_find_control_statement_thread_paths (cond, visited_bbs, bb_path,
                                               false);
 
-      pointer_set_destroy (visited_phis);
+      pointer_set_destroy (visited_bbs);
       vec_free (bb_path);
     }
   return 0;
-- 
2.1.0.243.g30d45f7

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