[stage1] Make parloops gate more strict

Move parloops::execute test to parloops gate

2015-06-11  Tom de Vries  <tom@codesourcery.com>

	* cfgloop.c (init_loops_structure): Add and handle dummy_p parameter.
	(flow_loops_find): Add extra argument to call to init_loops_structure.
	* cfgloop.h (init_loops_structure): Add bool parameter.
	* cgraphunit.c (init_lowered_empty_function): Add extra argument to call
	to init_loops_structure.
	* lto-streamer-in.c (input_cfg): Same.
	* tree-cfg.c (move_sese_region_to_fn): Same.
	* passes.c (pass_manager::dump_passes): Add dummy loops structure to
	dummy function.
	* tree-parloops.c (pass_parallelize_loops::execute): Move early-exit
	test to ..
	(pass_parallelize_loops::gate): ... here.
---
 gcc/cfgloop.c         | 19 +++++++++++--------
 gcc/cfgloop.h         |  2 +-
 gcc/cgraphunit.c      |  2 +-
 gcc/lto-streamer-in.c |  2 +-
 gcc/passes.c          |  4 ++++
 gcc/tree-cfg.c        |  2 +-
 gcc/tree-parloops.c   |  6 ++----
 7 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/gcc/cfgloop.c b/gcc/cfgloop.c
index a279046..2b17585 100644
--- a/gcc/cfgloop.c
+++ b/gcc/cfgloop.c
@@ -356,8 +356,8 @@  alloc_loop (void)
    (including the root of the loop tree).  */
 
 void
-init_loops_structure (struct function *fn,
-		      struct loops *loops, unsigned num_loops)
+init_loops_structure (struct function *fn, struct loops *loops,
+		      unsigned num_loops, bool dummy_p)
 {
   struct loop *root;
 
@@ -366,11 +366,14 @@  init_loops_structure (struct function *fn,
 
   /* Dummy loop containing whole function.  */
   root = alloc_loop ();
-  root->num_nodes = n_basic_blocks_for_fn (fn);
-  root->latch = EXIT_BLOCK_PTR_FOR_FN (fn);
-  root->header = ENTRY_BLOCK_PTR_FOR_FN (fn);
-  ENTRY_BLOCK_PTR_FOR_FN (fn)->loop_father = root;
-  EXIT_BLOCK_PTR_FOR_FN (fn)->loop_father = root;
+  if (!dummy_p)
+    {
+      root->num_nodes = n_basic_blocks_for_fn (fn);
+      root->latch = EXIT_BLOCK_PTR_FOR_FN (fn);
+      root->header = ENTRY_BLOCK_PTR_FOR_FN (fn);
+      ENTRY_BLOCK_PTR_FOR_FN (fn)->loop_father = root;
+      EXIT_BLOCK_PTR_FOR_FN (fn)->loop_father = root;
+    }
 
   loops->larray->quick_push (root);
   loops->tree_root = root;
@@ -427,7 +430,7 @@  flow_loops_find (struct loops *loops)
   if (!loops)
     {
       loops = ggc_cleared_alloc<struct loops> ();
-      init_loops_structure (cfun, loops, 1);
+      init_loops_structure (cfun, loops, 1, false);
     }
 
   /* Ensure that loop exits were released.  */
diff --git a/gcc/cfgloop.h b/gcc/cfgloop.h
index d811c56..e680941 100644
--- a/gcc/cfgloop.h
+++ b/gcc/cfgloop.h
@@ -260,7 +260,7 @@  struct GTY (()) loops {
 
 /* Loop recognition.  */
 bool bb_loop_header_p (basic_block);
-void init_loops_structure (struct function *, struct loops *, unsigned);
+void init_loops_structure (struct function *, struct loops *, unsigned, bool);
 extern struct loops *flow_loops_find (struct loops *);
 extern void disambiguate_loops_with_multiple_latches (void);
 extern void flow_loops_free (struct loops *);
diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c
index 722c4f4..d946b8f 100644
--- a/gcc/cgraphunit.c
+++ b/gcc/cgraphunit.c
@@ -1392,7 +1392,7 @@  init_lowered_empty_function (tree decl, bool in_ssa, gcov_type count)
 			    | PROP_cfg | PROP_loops);
 
   set_loops_for_fn (cfun, ggc_cleared_alloc<loops> ());
-  init_loops_structure (cfun, loops_for_fn (cfun), 1);
+  init_loops_structure (cfun, loops_for_fn (cfun), 1, false);
   loops_for_fn (cfun)->state |= LOOPS_MAY_HAVE_MULTIPLE_LATCHES;
 
   /* Create BB for body of the function and connect it properly.  */
diff --git a/gcc/lto-streamer-in.c b/gcc/lto-streamer-in.c
index 1b83615..9139c35 100644
--- a/gcc/lto-streamer-in.c
+++ b/gcc/lto-streamer-in.c
@@ -844,7 +844,7 @@  input_cfg (struct lto_input_block *ib, struct data_in *data_in,
     return;
 
   struct loops *loops = ggc_cleared_alloc<struct loops> ();
-  init_loops_structure (fn, loops, n_loops);
+  init_loops_structure (fn, loops, n_loops, false);
   set_loops_for_fn (fn, loops);
 
   /* Input each loop and associate it with its loop header so
diff --git a/gcc/passes.c b/gcc/passes.c
index 720e647..4d89fce 100644
--- a/gcc/passes.c
+++ b/gcc/passes.c
@@ -993,6 +993,10 @@  pass_manager::dump_passes () const
 {
   push_dummy_function (true);
 
+  /* Push dummy loop.  */
+  set_loops_for_fn (cfun, ggc_cleared_alloc<loops> ());
+  init_loops_structure (cfun, loops_for_fn (cfun), 1, true);
+
   create_pass_tab ();
 
   dump_pass_list (all_lowering_passes, 1);
diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
index b8a1c86..3bb7ea1 100644
--- a/gcc/tree-cfg.c
+++ b/gcc/tree-cfg.c
@@ -7122,7 +7122,7 @@  move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
 
   /* Initialize an empty loop tree.  */
   struct loops *loops = ggc_cleared_alloc<struct loops> ();
-  init_loops_structure (dest_cfun, loops, 1);
+  init_loops_structure (dest_cfun, loops, 1, false);
   loops->state = LOOPS_MAY_HAVE_MULTIPLE_LATCHES;
   set_loops_for_fn (dest_cfun, loops);
 
diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c
index a1659a3..ef98878 100644
--- a/gcc/tree-parloops.c
+++ b/gcc/tree-parloops.c
@@ -2657,7 +2657,8 @@  public:
     {
       return (flag_tree_parallelize_loops > 1
 	      && !parallelized_function_p (fun->decl)
-	      && !cfun->has_nonlocal_label);
+	      && !cfun->has_nonlocal_label
+	      && number_of_loops (fun) > 1);
     }
   virtual unsigned int execute (function *);
 
@@ -2666,9 +2667,6 @@  public:
 unsigned
 pass_parallelize_loops::execute (function *fun)
 {
-  if (number_of_loops (fun) <= 1)
-    return 0;
-
   if (parallelize_loops ())
     {
       fun->curr_properties &= ~(PROP_gimple_eomp);
-- 
1.9.1