tree-ssa-alias.c (walk_aliased_vdefs_1): Add FUNCTION_ENTRY_REACHED parameter.

	* tree-ssa-alias.c (walk_aliased_vdefs_1): Add FUNCTION_ENTRY_REACHED
	parameter.
	(walk_aliased_vdefs): Likewise.
	* tree-ssa-alias.h (walk_aliased_vdefs): Likewise.
	* ipa-prop.c (stmt_may_be_vtbl_ptr_store): Skip clobbers
	(detect_type_change_from_memory_writes): Check if entry was reached.

From-SVN: r212351

4 files changed, 37 insertions, 9 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3dcd84a..084aa13 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2014-07-08  Jan Hubicka  <hubicka@ucw.cz>
+
+	* tree-ssa-alias.c (walk_aliased_vdefs_1): Add FUNCTION_ENTRY_REACHED
+	parameter.
+	(walk_aliased_vdefs): Likewise.
+	* tree-ssa-alias.h (walk_aliased_vdefs): Likewise.
+	* ipa-prop.c (stmt_may_be_vtbl_ptr_store): Skip clobbers
+	(detect_type_change_from_memory_writes): Check if entry was reached.
+
 2014-07-08  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/61681
diff --git a/gcc/ipa-prop.c b/gcc/ipa-prop.c
index 34e766d..c6dd610 100644
--- a/gcc/ipa-prop.c
+++ b/gcc/ipa-prop.c
@@ -638,7 +638,8 @@ stmt_may_be_vtbl_ptr_store (gimple stmt)
 {
   if (is_gimple_call (stmt))
     return false;
-  /* TODO: Skip clobbers, doing so triggers problem in PR60306.  */
+  if (gimple_clobber_p (stmt))
+    return false;
   else if (is_gimple_assign (stmt))
     {
       tree lhs = gimple_assign_lhs (stmt);
@@ -817,6 +818,7 @@ detect_type_change_from_memory_writes (tree arg, tree base, tree comp_type,
 {
   struct type_change_info tci;
   ao_ref ao;
+  bool entry_reached = false;
 
   gcc_checking_assert (DECL_P (arg)
 		       || TREE_CODE (arg) == MEM_REF
@@ -847,13 +849,16 @@ detect_type_change_from_memory_writes (tree arg, tree base, tree comp_type,
   tci.multiple_types_encountered = false;
 
   walk_aliased_vdefs (&ao, gimple_vuse (call), check_stmt_for_type_change,
-		      &tci, NULL);
+		      &tci, NULL, &entry_reached);
   if (!tci.type_maybe_changed)
     return false;
 
   if (!tci.known_current_type
       || tci.multiple_types_encountered
-      || offset != 0)
+      || offset != 0
+      /* When the walk reached function entry, it means that type
+	 is set along some paths but not along others.  */
+      || entry_reached)
     jfunc->type = IPA_JF_UNKNOWN;
   else
     ipa_set_jf_known_type (jfunc, 0, tci.known_current_type, comp_type);
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
index 5cc9cb5..5a8f7bd 100644
--- a/gcc/tree-ssa-alias.c
+++ b/gcc/tree-ssa-alias.c
@@ -2643,6 +2643,9 @@ walk_non_aliased_vuses (ao_ref *ref, tree vuse,
    WALKER is called with REF, the current vdef and DATA.  If WALKER
    returns true the walk is stopped, otherwise it continues.
 
+   If function entry is reached, FUNCTION_ENTRY_REACHED is set to true.
+   The pointer may be NULL and then we do not track this information.
+
    At PHI nodes walk_aliased_vdefs forks into one walk for reach
    PHI argument (but only one walk continues on merge points), the
    return value is true if any of the walks was successful.
@@ -2652,8 +2655,11 @@ walk_non_aliased_vuses (ao_ref *ref, tree vuse,
 static unsigned int
 walk_aliased_vdefs_1 (ao_ref *ref, tree vdef,
 		      bool (*walker)(ao_ref *, tree, void *), void *data,
-		      bitmap *visited, unsigned int cnt)
+		      bitmap *visited, unsigned int cnt,
+		      bool *function_entry_reached)
 {
+  if (function_entry_reached)
+    *function_entry_reached = false;
   do
     {
       gimple def_stmt = SSA_NAME_DEF_STMT (vdef);
@@ -2663,7 +2669,11 @@ walk_aliased_vdefs_1 (ao_ref *ref, tree vdef,
 	return cnt;
 
       if (gimple_nop_p (def_stmt))
-	return cnt;
+	{
+	  if (function_entry_reached)
+	    *function_entry_reached = true;
+	  return cnt;
+	}
       else if (gimple_code (def_stmt) == GIMPLE_PHI)
 	{
 	  unsigned i;
@@ -2671,7 +2681,8 @@ walk_aliased_vdefs_1 (ao_ref *ref, tree vdef,
 	    *visited = BITMAP_ALLOC (NULL);
 	  for (i = 0; i < gimple_phi_num_args (def_stmt); ++i)
 	    cnt += walk_aliased_vdefs_1 (ref, gimple_phi_arg_def (def_stmt, i),
-					 walker, data, visited, 0);
+					 walker, data, visited, 0,
+					 function_entry_reached);
 	  return cnt;
 	}
 
@@ -2690,7 +2701,8 @@ walk_aliased_vdefs_1 (ao_ref *ref, tree vdef,
 unsigned int
 walk_aliased_vdefs (ao_ref *ref, tree vdef,
 		    bool (*walker)(ao_ref *, tree, void *), void *data,
-		    bitmap *visited)
+		    bitmap *visited,
+		    bool *function_entry_reached)
 {
   bitmap local_visited = NULL;
   unsigned int ret;
@@ -2698,7 +2710,8 @@ walk_aliased_vdefs (ao_ref *ref, tree vdef,
   timevar_push (TV_ALIAS_STMT_WALK);
 
   ret = walk_aliased_vdefs_1 (ref, vdef, walker, data,
-			      visited ? visited : &local_visited, 0);
+			      visited ? visited : &local_visited, 0,
+			      function_entry_reached);
   if (local_visited)
     BITMAP_FREE (local_visited);
 
diff --git a/gcc/tree-ssa-alias.h b/gcc/tree-ssa-alias.h
index c0b472b..e46f89e 100644
--- a/gcc/tree-ssa-alias.h
+++ b/gcc/tree-ssa-alias.h
@@ -123,7 +123,8 @@ extern void *walk_non_aliased_vuses (ao_ref *, tree,
 				     void *);
 extern unsigned int walk_aliased_vdefs (ao_ref *, tree,
 					bool (*)(ao_ref *, tree, void *),
-					void *, bitmap *);
+					void *, bitmap *,
+					bool *function_entry_reached = NULL);
 extern void dump_alias_info (FILE *);
 extern void debug_alias_info (void);
 extern void dump_points_to_solution (FILE *, struct pt_solution *);