tree-ssa-threadupdate.c (thread_through_all_blocks): Record that the loop structures may need fixing.

* tree-ssa-threadupdate.c (thread_through_all_blocks): Record that
	the loop structures may need fixing.
	* tree-cfgcleanup.c (cleanup_tree_cfg_noloop, repair_loop_structures):
	New functions.
	(cleanup_tree_cfg_loop): Removed.
	(cleanup_tree_cfg): If loops need fixing, call repair_loop_structures.
	* tree-predcom.c (tree_predictive_commoning): Return TODO_cleanup_cfg
	instead of running cleanup_tree_cfg_loop.
	* cfgloop.h (LOOPS_NEED_FIXUP): New constant.
	* tree-flow.h (cleanup_tree_cfg_loop): Declaration removed.
	(tree_predictive_commoning): Declaration changed.
	* passes.c (execute_function_todo): Do not use cleanup_tree_cfg_loop.

From-SVN: r127118

gcc/ChangeLog

@@ -1,3 +1,18 @@
+2007-08-01  Zdenek Dvorak  <ook@ucw.cz>
+
+	* tree-ssa-threadupdate.c (thread_through_all_blocks): Record that
+	the loop structures may need fixing.
+	* tree-cfgcleanup.c (cleanup_tree_cfg_noloop, repair_loop_structures):
+	New functions.
+	(cleanup_tree_cfg_loop): Removed.
+	(cleanup_tree_cfg): If loops need fixing, call repair_loop_structures.
+	* tree-predcom.c (tree_predictive_commoning): Return TODO_cleanup_cfg
+	instead of running cleanup_tree_cfg_loop.
+	* cfgloop.h (LOOPS_NEED_FIXUP): New constant.
+	* tree-flow.h (cleanup_tree_cfg_loop): Declaration removed.
+	(tree_predictive_commoning): Declaration changed.
+	* passes.c (execute_function_todo): Do not use cleanup_tree_cfg_loop.
+
 2007-08-01  Zdenek Dvorak  <ook@ucw.cz>
 
 	* doc/invoke.texi (l1-cache-size): Update documentation.

gcc/cfgloop.h

@@ -170,7 +170,8 @@ enum
   LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS = 4,
   LOOPS_HAVE_RECORDED_EXITS = 8,
   LOOPS_MAY_HAVE_MULTIPLE_LATCHES = 16,
-  LOOP_CLOSED_SSA = 32
+  LOOP_CLOSED_SSA = 32,
+  LOOPS_NEED_FIXUP = 64
 };
 
 #define LOOPS_NORMAL (LOOPS_HAVE_PREHEADERS | LOOPS_HAVE_SIMPLE_LATCHES \

gcc/passes.c

@@ -891,12 +891,7 @@ execute_function_todo (void *data)
   /* Always cleanup the CFG before trying to update SSA.  */
   if (flags & TODO_cleanup_cfg)
     {
-      bool cleanup;
-
-      if (current_loops)
-	cleanup = cleanup_tree_cfg_loop ();
-      else
-	cleanup = cleanup_tree_cfg ();
+      bool cleanup = cleanup_tree_cfg ();
 
       if (cleanup && (cfun->curr_properties & PROP_ssa))
 	flags |= TODO_remove_unused_locals;

gcc/tree-cfgcleanup.c

@@ -596,8 +596,8 @@ cleanup_tree_cfg_1 (void)
 /* Remove unreachable blocks and other miscellaneous clean up work.
    Return true if the flowgraph was modified, false otherwise.  */
 
-bool
-cleanup_tree_cfg (void)
+static bool
+cleanup_tree_cfg_noloop (void)
 {
   bool changed;
 
@@ -632,34 +632,47 @@ cleanup_tree_cfg (void)
 
   timevar_pop (TV_TREE_CLEANUP_CFG);
 
+  if (changed && current_loops)
+    current_loops->state |= LOOPS_NEED_FIXUP;
+
   return changed;
 }
 
+/* Repairs loop structures.  */
+
+static void
+repair_loop_structures (void)
+{
+  bitmap changed_bbs = BITMAP_ALLOC (NULL);
+  fix_loop_structure (changed_bbs);
+
+  /* This usually does nothing.  But sometimes parts of cfg that originally
+     were inside a loop get out of it due to edge removal (since they
+     become unreachable by back edges from latch).  */
+  if ((current_loops->state & LOOP_CLOSED_SSA) != 0)
+    rewrite_into_loop_closed_ssa (changed_bbs, TODO_update_ssa);
+
+  BITMAP_FREE (changed_bbs);
+
+#ifdef ENABLE_CHECKING
+  verify_loop_structure ();
+#endif
+  scev_reset ();
+
+  current_loops->state &= ~LOOPS_NEED_FIXUP;
+}
+
 /* Cleanup cfg and repair loop structures.  */
 
 bool
-cleanup_tree_cfg_loop (void)
+cleanup_tree_cfg (void)
 {
-  bool changed = cleanup_tree_cfg ();
+  bool changed = cleanup_tree_cfg_noloop ();
 
-  if (changed && current_loops != NULL)
-    {
-      bitmap changed_bbs = BITMAP_ALLOC (NULL);
-      fix_loop_structure (changed_bbs);
+  if (current_loops != NULL
+      && (current_loops->state & LOOPS_NEED_FIXUP))
+    repair_loop_structures ();
 
-      /* This usually does nothing.  But sometimes parts of cfg that originally
-	 were inside a loop get out of it due to edge removal (since they
-	 become unreachable by back edges from latch).  */
-      if ((current_loops->state & LOOP_CLOSED_SSA) != 0)
-	rewrite_into_loop_closed_ssa (changed_bbs, TODO_update_ssa);
-
-      BITMAP_FREE (changed_bbs);
-
-#ifdef ENABLE_CHECKING
-      verify_loop_structure ();
-#endif
-      scev_reset ();
-    }
   return changed;
 }
 

gcc/tree-flow.h

@@ -783,7 +783,6 @@ void remove_edge_and_dominated_blocks (edge);
 /* In tree-cfgcleanup.c  */
 extern bitmap cfgcleanup_altered_bbs;
 extern bool cleanup_tree_cfg (void);
-extern bool cleanup_tree_cfg_loop (void);
 
 /* In tree-pretty-print.c.  */
 extern void dump_generic_bb (FILE *, basic_block, int, int);
@@ -975,7 +974,7 @@ unsigned int tree_unroll_loops_completely (bool);
 unsigned int tree_ssa_prefetch_arrays (void);
 unsigned int remove_empty_loops (void);
 void tree_ssa_iv_optimize (void);
-void tree_predictive_commoning (void);
+unsigned tree_predictive_commoning (void);
 
 bool number_of_iterations_exit (struct loop *, edge,
 				struct tree_niter_desc *niter, bool);

gcc/tree-predcom.c

@@ -2582,12 +2582,13 @@ end: ;
 
 /* Runs predictive commoning.  */
 
-void
+unsigned
 tree_predictive_commoning (void)
 {
   bool unrolled = false;
   struct loop *loop;
   loop_iterator li;
+  unsigned ret = 0;
 
   initialize_original_copy_tables ();
   FOR_EACH_LOOP (li, loop, LI_ONLY_INNERMOST)
@@ -2598,7 +2599,9 @@ tree_predictive_commoning (void)
   if (unrolled)
     {
       scev_reset ();
-      cleanup_tree_cfg_loop ();
+      ret = TODO_cleanup_cfg;
     }
   free_original_copy_tables ();
+
+  return ret;
 }

gcc/tree-ssa-threadupdate.c

@@ -1076,6 +1076,9 @@ thread_through_all_blocks (bool may_peel_loop_headers)
   VEC_free (edge, heap, threaded_edges);
   threaded_edges = NULL;
 
+  if (retval)
+    current_loops->state |= LOOPS_NEED_FIXUP;
+
   return retval;
 }