[google gcc-4_7] change LIPO default module grouping algorithm (issue7490043)

[xur at google dot com (Rong Xu)]

Hi,

This patch changes the default lipo module grouping
algorithm from algoritm 0 (eager propagation algorithm)
to algorith 1 (inclusion_based priority algorithm).

It also changes the name __gcov_lipo_strict_inclusion
to __gcov_lipo_weak_inclusion and the default is 0.

Tested with google internal benchmarks.

-Rong

2013-03-05  Rong Xu  <xur@google.com>

	* libgcc/dyn-ipa.c (__gcov_lipo_weak_inclusion):
        changed from __gcov_lipo_strict_inclusion.
	(init_dyn_call_graph): Ditto.
	(ps_add_auxiliary): Ditto.
	(modu_edge_add_auxiliary): Ditto.
	* gcc/tree-profile.c (tree_init_dyn_ipa_parameters): Ditto.
	* gcc/params.def (PARAM_LIPO_GROUPING_ALGORITHM): Changed
        default value from 0 to 1.

Index: libgcc/dyn-ipa.c
===================================================================
--- libgcc/dyn-ipa.c	(revision 196405)
+++ libgcc/dyn-ipa.c	(working copy)
@@ -157,7 +157,7 @@ extern gcov_unsigned_t __gcov_lipo_dump_cgraph;
 extern gcov_unsigned_t __gcov_lipo_max_mem;
 extern gcov_unsigned_t __gcov_lipo_grouping_algorithm;
 extern gcov_unsigned_t __gcov_lipo_merge_modu_edges;
-extern gcov_unsigned_t __gcov_lipo_strict_inclusion;
+extern gcov_unsigned_t __gcov_lipo_weak_inclusion;
 
 #if defined(inhibit_libc)
 __gcov_build_callgraph (void) {}
@@ -195,7 +195,7 @@ enum GROUPING_ALGORITHM
 };
 static int flag_alg_mode;
 static int flag_modu_merge_edges;
-static int flag_strict_inclusion;
+static int flag_weak_inclusion;
 static gcov_unsigned_t mem_threshold;
 
 /* Returns 0 if no dump is enabled. Returns 1 if text form graph
@@ -387,7 +387,7 @@ init_dyn_call_graph (void)
 
   flag_alg_mode = __gcov_lipo_grouping_algorithm;
   flag_modu_merge_edges = __gcov_lipo_merge_modu_edges;
-  flag_strict_inclusion = __gcov_lipo_strict_inclusion;
+  flag_weak_inclusion = __gcov_lipo_weak_inclusion;
   mem_threshold = __gcov_lipo_max_mem * 1.25;
 
   gi_ptr = __gcov_list;
@@ -417,13 +417,13 @@ init_dyn_call_graph (void)
       if ((env_str = getenv ("GCOV_DYN_MERGE_EDGES")))
         flag_modu_merge_edges = atoi (env_str);
 
-      if ((env_str = getenv ("GCOV_DYN_STRICT_INCLUSION")))
-        flag_strict_inclusion = atoi (env_str);
+      if ((env_str = getenv ("GCOV_DYN_WEAK_INCLUSION")))
+        flag_weak_inclusion = atoi (env_str);
 
       if (do_dump)
 	fprintf (stderr, 
-            "!!!! Using ALG=%d merge_edges=%d strict_inclusion=%d. \n",
-            flag_alg_mode, flag_modu_merge_edges, flag_strict_inclusion);
+            "!!!! Using ALG=%d merge_edges=%d weak_inclusion=%d. \n",
+            flag_alg_mode, flag_modu_merge_edges, flag_weak_inclusion);
     }
 
   if (do_dump)
@@ -1809,7 +1809,7 @@ ps_add_auxiliary (const void *value,
   int not_safe_to_insert = *(int *) data3;
   gcov_unsigned_t new_ggc_size;
 
-  /* For strict incluesion, we know it's safe to insert.  */
+  /* For strict inclusion, we know it's safe to insert.  */
   if (!not_safe_to_insert)
     {
       modu_add_auxiliary (m_id, s_m_id, *(gcov_type*)data2);
@@ -1825,7 +1825,8 @@ ps_add_auxiliary (const void *value,
   return 1;
 }
 
-/* return 1 if insertion happened, otherwise 0.  */
+/* Return 1 if insertion happened, otherwise 0.  */
+
 static int
 modu_edge_add_auxiliary (struct modu_edge *edge)
 {
@@ -1871,7 +1872,7 @@ modu_edge_add_auxiliary (struct modu_edge *edge)
     {
       pointer_set_traverse (node_exported_to, ps_check_ggc_mem,
                             &callee_m_id, &fail, 0);
-      if (fail && flag_strict_inclusion)
+      if (fail && !flag_weak_inclusion)
         return 0;
     }
 
Index: gcc/tree-profile.c
===================================================================
--- gcc/tree-profile.c	(revision 196471)
+++ gcc/tree-profile.c	(working copy)
@@ -389,10 +389,10 @@ tree_init_dyn_ipa_parameters (void)
       gcov_lipo_strict_inclusion = build_decl (
           UNKNOWN_LOCATION,
           VAR_DECL,
-          get_identifier ("__gcov_lipo_strict_inclusion"),
+          get_identifier ("__gcov_lipo_weak_inclusion"),
           get_gcov_unsigned_t ());
       init_comdat_decl (gcov_lipo_strict_inclusion,
-                        PARAM_LIPO_STRICT_INCLUSION);
+                        PARAM_LIPO_WEAK_INCLUSION);
     }
 }
 
Index: gcc/params.def
===================================================================
--- gcc/params.def	(revision 196471)
+++ gcc/params.def	(working copy)
@@ -1018,25 +1018,26 @@ DEFPARAM (PARAM_INLINE_DUMP_MODULE_ID,
    LIPO profile-gen.  */
 DEFPARAM (PARAM_LIPO_GROUPING_ALGORITHM,
 	  "lipo-grouping-algorithm",
-	  "Default is 0 which is the eager propagation algorithm."
-          "If the value is 1, use the inclusion_based priority algorithm.",
-	  0, 0, 1)
+	  "Algorithm 0 uses the eager propagation algorithm."
+	  "Algorithm 1 uses the inclusion_based priority algorithm."
+	  "The default algorithm is 1.",
+	  1, 0, 1)
 
 /* In the inclusion_based_priority grouping algorithm, specify if we combine the
    the edges b/w modules.  */
 DEFPARAM (PARAM_LIPO_MERGE_MODU_EDGES,
 	  "lipo-merge-modu-edges",
 	  "Default is 0 which not merge."
-          "If the value is 1, merge the edges.",
+	  "If the value is 1, merge the edges.",
 	  0, 0, 1)
 
 /* In the inclusion_based_priority grouping algorithm, specify if we force
    strict inclusion of modules.  */
-DEFPARAM (PARAM_LIPO_STRICT_INCLUSION,
-	  "lipo-strict-inclusion",
-	  "0: not strict inclusion; 1: force strict inclusion."
-          "Default is 1.",
-	  1, 0, 1)
+DEFPARAM (PARAM_LIPO_WEAK_INCLUSION,
+	  "lipo-weak-inclusion",
+	  "0: force strict inclusion; 1: weak inclusion."
+	  "Default is 0.",
+	  0, 0, 1)
 
 /* In LIPO profile-gen, use this parameter to enable cgraph dumping.   */
 DEFPARAM (PARAM_LIPO_DUMP_CGRAPH,

--
This patch is available for review at http://codereview.appspot.com/7490043