cgraph.c (dump_cgraph_node): Dump same_comdat_group, only_called_at_startup and only_called_at_exit.

	* cgraph.c (dump_cgraph_node): Dump same_comdat_group,
	only_called_at_startup and only_called_at_exit.
	(cgraph_propagate_frequency): Compute only_called_at_startup and 
	only_called_at_exit.
	* cgraph.h (struct cgraph_node): New fileds only_called_at_startup and
	only_called_at_exit.
	* lto-cgraph.c (lto_output_node, input_overwrite_node): Stream the new
	flags.
	* predict.c (compute_function_frequency): Initialize the new flags.

From-SVN: r165560

5 files changed, 91 insertions, 20 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 375404c..7c3dc3b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2010-10-16  Jan Hubicka  <jh@suse.cz>
+
+	* cgraph.c (dump_cgraph_node): Dump same_comdat_group,
+	only_called_at_startup and only_called_at_exit.
+	(cgraph_propagate_frequency): Compute only_called_at_startup and 
+	only_called_at_exit.
+	* cgraph.h (struct cgraph_node): New fileds only_called_at_startup and
+	only_called_at_exit.
+	* lto-cgraph.c (lto_output_node, input_overwrite_node): Stream the new
+	flags.
+	* predict.c (compute_function_frequency): Initialize the new flags.
+
 2010-10-16  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gimplify.c (gimplify_type_sizes) <ARRAY_TYPE>: If the type is to be
diff --git a/gcc/cgraph.c b/gcc/cgraph.c
index 465e9af..342ad63 100644
--- a/gcc/cgraph.c
+++ b/gcc/cgraph.c
@@ -1816,6 +1816,10 @@ dump_cgraph_node (FILE *f, struct cgraph_node *node)
     fprintf (f, " (inline copy in %s/%i)",
 	     cgraph_node_name (node->global.inlined_to),
 	     node->global.inlined_to->uid);
+  if (node->same_comdat_group)
+    fprintf (f, " (same comdat group as %s/%i)",
+	     cgraph_node_name (node->same_comdat_group),
+	     node->same_comdat_group->uid);
   if (node->clone_of)
     fprintf (f, " (clone of %s/%i)",
 	     cgraph_node_name (node->clone_of),
@@ -1876,6 +1880,10 @@ dump_cgraph_node (FILE *f, struct cgraph_node *node)
     fprintf (f, " redefined_extern_inline");
   if (TREE_ASM_WRITTEN (node->decl))
     fprintf (f, " asm_written");
+  if (node->only_called_at_startup)
+    fprintf (f, " only_called_at_startup");
+  if (node->only_called_at_exit)
+    fprintf (f, " only_called_at_exit");
 
   fprintf (f, "\n  called by: ");
   for (edge = node->callers; edge; edge = edge->next_caller)
@@ -2627,20 +2635,32 @@ bool
 cgraph_propagate_frequency (struct cgraph_node *node)
 {
   bool maybe_unlikely_executed = true, maybe_executed_once = true;
+  bool only_called_at_startup = true;
+  bool only_called_at_exit = true;
+  bool changed = false;
   struct cgraph_edge *edge;
+
   if (!node->local.local)
     return false;
   gcc_assert (node->analyzed);
-  if (node->frequency == NODE_FREQUENCY_HOT)
-    return false;
-  if (node->frequency == NODE_FREQUENCY_UNLIKELY_EXECUTED)
-    return false;
   if (dump_file && (dump_flags & TDF_DETAILS))
     fprintf (dump_file, "Processing frequency %s\n", cgraph_node_name (node));
+
   for (edge = node->callers;
-       edge && (maybe_unlikely_executed || maybe_executed_once);
+       edge && (maybe_unlikely_executed || maybe_executed_once
+	        || only_called_at_startup || only_called_at_exit);
        edge = edge->next_caller)
     {
+      if (edge->caller != node)
+	{
+          only_called_at_startup &= edge->caller->only_called_at_startup;
+	  /* It makes snese to put main() together with the static constructors.
+	     It will be executed for sure, but rest of functions called from
+	     main are definitly not at startup only.  */
+	  if (MAIN_NAME_P (DECL_NAME (edge->caller->decl)))
+	    only_called_at_startup = 0;
+          only_called_at_exit &= edge->caller->only_called_at_exit;
+	}
       if (!edge->frequency)
 	continue;
       switch (edge->caller->frequency)
@@ -2649,7 +2669,8 @@ cgraph_propagate_frequency (struct cgraph_node *node)
 	  break;
 	case NODE_FREQUENCY_EXECUTED_ONCE:
 	  if (dump_file && (dump_flags & TDF_DETAILS))
-	    fprintf (dump_file, "  Called by %s that is executed once\n", cgraph_node_name (node));
+	    fprintf (dump_file, "  Called by %s that is executed once\n",
+		     cgraph_node_name (node));
 	  maybe_unlikely_executed = false;
 	  if (edge->loop_nest)
 	    {
@@ -2661,27 +2682,52 @@ cgraph_propagate_frequency (struct cgraph_node *node)
 	case NODE_FREQUENCY_HOT:
 	case NODE_FREQUENCY_NORMAL:
 	  if (dump_file && (dump_flags & TDF_DETAILS))
-	    fprintf (dump_file, "  Called by %s that is normal or hot\n", cgraph_node_name (node));
+	    fprintf (dump_file, "  Called by %s that is normal or hot\n",
+		     cgraph_node_name (node));
 	  maybe_unlikely_executed = false;
 	  maybe_executed_once = false;
 	  break;
 	}
     }
-   if (maybe_unlikely_executed)
-     {
-       node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
+  if ((only_called_at_startup && !only_called_at_exit)
+      && !node->only_called_at_startup)
+    {
+       node->only_called_at_startup = true;
        if (dump_file)
-         fprintf (dump_file, "Node %s promoted to unlikely executed.\n", cgraph_node_name (node));
-       return true;
-     }
-   if (maybe_executed_once && node->frequency != NODE_FREQUENCY_EXECUTED_ONCE)
-     {
-       node->frequency = NODE_FREQUENCY_EXECUTED_ONCE;
+         fprintf (dump_file, "Node %s promoted to only called at startup.\n",
+		  cgraph_node_name (node));
+       changed = true;
+    }
+  if ((only_called_at_exit && !only_called_at_startup)
+      && !node->only_called_at_exit)
+    {
+       node->only_called_at_exit = true;
        if (dump_file)
-         fprintf (dump_file, "Node %s promoted to executed once.\n", cgraph_node_name (node));
-       return true;
-     }
-   return false;
+         fprintf (dump_file, "Node %s promoted to only called at exit.\n",
+		  cgraph_node_name (node));
+       changed = true;
+    }
+  /* These come either from profile or user hints; never update them.  */
+  if (node->frequency == NODE_FREQUENCY_HOT
+      || node->frequency == NODE_FREQUENCY_UNLIKELY_EXECUTED)
+    return changed;
+  if (maybe_unlikely_executed)
+    {
+      node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
+      if (dump_file)
+	fprintf (dump_file, "Node %s promoted to unlikely executed.\n",
+		 cgraph_node_name (node));
+      changed = true;
+    }
+  if (maybe_executed_once && node->frequency != NODE_FREQUENCY_EXECUTED_ONCE)
+    {
+      node->frequency = NODE_FREQUENCY_EXECUTED_ONCE;
+      if (dump_file)
+	fprintf (dump_file, "Node %s promoted to executed once.\n",
+		 cgraph_node_name (node));
+      changed = true;
+    }
+  return changed;
 }
 
 /* Return true when NODE can not return or throw and thus
diff --git a/gcc/cgraph.h b/gcc/cgraph.h
index d7ca67c..ea95f70 100644
--- a/gcc/cgraph.h
+++ b/gcc/cgraph.h
@@ -298,6 +298,10 @@ struct GTY((chain_next ("%h.next"), chain_prev ("%h.previous"))) cgraph_node {
   /* How commonly executed the node is.  Initialized during branch
      probabilities pass.  */
   ENUM_BITFIELD (node_frequency) frequency : 2;
+  /* True when function can only be called at startup (from static ctor).  */
+  unsigned only_called_at_startup : 1;
+  /* True when function can only be called at startup (from static dtor).  */
+  unsigned only_called_at_exit : 1;
 };
 
 typedef struct cgraph_node *cgraph_node_ptr;
diff --git a/gcc/lto-cgraph.c b/gcc/lto-cgraph.c
index b61e5d1..85a7c40 100644
--- a/gcc/lto-cgraph.c
+++ b/gcc/lto-cgraph.c
@@ -518,6 +518,8 @@ lto_output_node (struct lto_simple_output_block *ob, struct cgraph_node *node,
   bp_pack_value (&bp, node->alias, 1);
   bp_pack_value (&bp, node->finalized_by_frontend, 1);
   bp_pack_value (&bp, node->frequency, 2);
+  bp_pack_value (&bp, node->only_called_at_startup, 1);
+  bp_pack_value (&bp, node->only_called_at_exit, 1);
   lto_output_bitpack (&bp);
   lto_output_uleb128_stream (ob->main_stream, node->resolution);
 
@@ -978,6 +980,8 @@ input_overwrite_node (struct lto_file_decl_data *file_data,
   node->alias = bp_unpack_value (bp, 1);
   node->finalized_by_frontend = bp_unpack_value (bp, 1);
   node->frequency = (enum node_frequency)bp_unpack_value (bp, 2);
+  node->only_called_at_startup = bp_unpack_value (bp, 1);
+  node->only_called_at_exit = bp_unpack_value (bp, 1);
   node->resolution = resolution;
 }
 
diff --git a/gcc/predict.c b/gcc/predict.c
index 1b61ee4..eb91b87 100644
--- a/gcc/predict.c
+++ b/gcc/predict.c
@@ -2187,6 +2187,11 @@ compute_function_frequency (void)
 {
   basic_block bb;
   struct cgraph_node *node = cgraph_node (current_function_decl);
+  if (DECL_STATIC_CONSTRUCTOR (current_function_decl)
+      || MAIN_NAME_P (DECL_NAME (current_function_decl)))
+    node->only_called_at_startup = true;
+  if (DECL_STATIC_DESTRUCTOR (current_function_decl))
+    node->only_called_at_exit = true;
 
   if (!profile_info || !flag_branch_probabilities)
     {