2012-01-04 Richard Guenther <rguenther@suse.de>

	PR tree-optimization/49651
	* tree-ssa-structalias.c (type_can_have_subvars): New function.
	(var_can_have_subvars): Use it.
	(get_constraint_for_1): Only consider subfields if there
	can be any.

	* gcc.dg/tree-ssa/pta-ptrarith-1.c: Adjust.
	* gcc.dg/tree-ssa/pta-ptrarith-2.c: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@182865 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b4c5fa1..78e69a7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2012-01-04  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/49651
+       * tree-ssa-structalias.c (type_can_have_subvars): New function.
+       (var_can_have_subvars): Use it.
+       (get_constraint_for_1): Only consider subfields if there
+       can be any.
+
 2012-01-03  Jakub Jelinek  <jakub@redhat.com>
 
        PR bootstrap/51725

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8fa86a8..556e676 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2012-01-04  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/49651
+       * gcc.dg/tree-ssa/pta-ptrarith-1.c: Adjust.
+       * gcc.dg/tree-ssa/pta-ptrarith-2.c: Likewise.
+
 2012-01-03  Paolo Carlini  <paolo.carlini@oracle.com>
 
        PR c++/51738

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-1.c
index 6db9ba0..2a60e1d 100644 (file)
--- a/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-1.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-1.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-O2 -fno-tree-ccp -fdump-tree-ealias" } */
+/* { dg-options "-O2 -fno-tree-forwprop -fno-tree-ccp -fdump-tree-ealias" } */
 
 extern void abort (void);
 struct X {

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-2.c b/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-2.c
index 85b96b1..ddf934b 100644 (file)
--- a/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-2.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pta-ptrarith-2.c
@@ -1,5 +1,5 @@
 /* { dg-do compile } */
-/* { dg-options "-O2 -fno-tree-ccp -fdump-tree-ealias" } */
+/* { dg-options "-O2 -fno-tree-forwprop -fno-tree-ccp -fdump-tree-ealias" } */
 
 extern void abort (void);
 struct X {

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 56ffca5..5a55d16 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -303,6 +303,7 @@ static varinfo_t first_vi_for_offset (varinfo_t, unsigned HOST_WIDE_INT);
 static varinfo_t first_or_preceding_vi_for_offset (varinfo_t,
                                                   unsigned HOST_WIDE_INT);
 static varinfo_t lookup_vi_for_tree (tree);
+static inline bool type_can_have_subvars (const_tree);
 
 /* Pool of variable info structures.  */
 static alloc_pool variable_info_pool;
@@ -3275,7 +3276,8 @@ get_constraint_for_1 (tree t, VEC (ce_s, heap) **results, bool address_p,
                return;
 
              cs = *VEC_last (ce_s, *results);
-             if (cs.type == DEREF)
+             if (cs.type == DEREF
+                 && type_can_have_subvars (TREE_TYPE (t)))
                {
                  /* For dereferences this means we have to defer it
                     to solving time.  */
@@ -5043,6 +5045,15 @@ sort_fieldstack (VEC(fieldoff_s,heap) *fieldstack)
   VEC_qsort (fieldoff_s, fieldstack, fieldoff_compare);
 }
 
+/* Return true if T is a type that can have subvars.  */
+
+static inline bool
+type_can_have_subvars (const_tree t)
+{
+  /* Aggregates without overlapping fields can have subvars.  */
+  return TREE_CODE (t) == RECORD_TYPE;
+}
+
 /* Return true if V is a tree that we can have subvars for.
    Normally, this is any aggregate type.  Also complex
    types which are not gimple registers can have subvars.  */
@@ -5058,11 +5069,7 @@ var_can_have_subvars (const_tree v)
   if (!DECL_P (v))
     return false;
 
-  /* Aggregates without overlapping fields can have subvars.  */
-  if (TREE_CODE (TREE_TYPE (v)) == RECORD_TYPE)
-    return true;
-
-  return false;
+  return type_can_have_subvars (TREE_TYPE (v));
 }
 
 /* Return true if T is a type that does contain pointers.  */