tree-ssa-alias.c (ptrs_compare_unequal): Remove code duplication.

2016-10-20  Richard Biener  <rguenther@suse.de>

	* tree-ssa-alias.c (ptrs_compare_unequal): Remove code duplication.
	Handle decls possibly not bound.
	* tree-ssa-structalias.c (get_constraint_for_ssa_var): Add
	nothing_id for decls that might not be bound if we are interested
	for the address.
	(get_constraint_for_component_ref): Deal with that.

From-SVN: r241378

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 4265d0871075d682dd603de2ed6f482c6f7f0103..2c770c240ec48d7e46acdee35429e80d06001c4e 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2016-10-20  Richard Biener  <rguenther@suse.de>
+
+       * tree-ssa-alias.c (ptrs_compare_unequal): Remove code duplication.
+       Handle decls possibly not bound.
+       * tree-ssa-structalias.c (get_constraint_for_ssa_var): Add
+       nothing_id for decls that might not be bound if we are interested
+       for the address.
+       (get_constraint_for_component_ref): Deal with that.
+
 2016-10-20  Michael Matz  <matz@suse.de>
 
        Loop splitting.

diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
index 01bef17cbfb558336a499e6754076589d3d2a6cf..26c9f9e894b78f2dce72c017f27e2fb84e090019 100644 (file)
--- a/gcc/tree-ssa-alias.c
+++ b/gcc/tree-ssa-alias.c
@@ -358,6 +358,13 @@ ptrs_compare_unequal (tree ptr1, tree ptr2)
        ptr2 = TREE_OPERAND (tem, 0);
     }
 
+  /* Canonicalize ptr vs. object.  */
+  if (TREE_CODE (ptr1) == SSA_NAME && obj2)
+    {
+      std::swap (ptr1, ptr2);
+      std::swap (obj1, obj2);
+    }
+
   if (obj1 && obj2)
     /* Other code handles this correctly, no need to duplicate it here.  */;
   else if (obj1 && TREE_CODE (ptr2) == SSA_NAME)
@@ -368,15 +375,16 @@ ptrs_compare_unequal (tree ptr1, tree ptr2)
         may be in fact obj1.  */
       if (!pi || pi->pt.vars_contains_restrict)
        return false;
+      if (VAR_P (obj1)
+         && (TREE_STATIC (obj1) || DECL_EXTERNAL (obj1)))
+       {
+         varpool_node *node = varpool_node::get (obj1);
+         /* If obj1 may bind to NULL give up (see below).  */
+         if (! node || ! node->nonzero_address ())
+           return false;
+       }
       return !pt_solution_includes (&pi->pt, obj1);
     }
-  else if (TREE_CODE (ptr1) == SSA_NAME && obj2)
-    {
-      struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr1);
-      if (!pi || pi->pt.vars_contains_restrict)
-       return false;
-      return !pt_solution_includes (&pi->pt, obj2);
-    }
 
   /* ???  We'd like to handle ptr1 != NULL and ptr1 != ptr2
      but those require pt.null to be conservatively correct.  */

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 78f45334785071e9ffdf973eb5177c7732677533..fb364f1319d668e1ade94985d84f916cf9e551dc 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -2944,6 +2944,16 @@ get_constraint_for_ssa_var (tree t, vec<ce_s> *results, bool address_p)
          DECL_PT_UID (t) = DECL_UID (node->decl);
          t = node->decl;
        }
+
+      /* If this is decl may bind to NULL note that.  */
+      if (address_p
+         && (! node || ! node->nonzero_address ()))
+       {
+         cexpr.var = nothing_id;
+         cexpr.type = SCALAR;
+         cexpr.offset = 0;
+         results->safe_push (cexpr);
+       }
     }
 
   vi = get_vi_for_tree (t);
@@ -3213,6 +3223,12 @@ get_constraint_for_component_ref (tree t, vec<ce_s> *results,
   /* Pretend to take the address of the base, we'll take care of
      adding the required subset of sub-fields below.  */
   get_constraint_for_1 (t, results, true, lhs_p);
+  /* Strip off nothing_id.  */
+  if (results->length () == 2)
+    {
+      gcc_assert ((*results)[0].var == nothing_id);
+      results->unordered_remove (0);
+    }
   gcc_assert (results->length () == 1);
   struct constraint_expr &result = results->last ();