tree-ssa-structalias.c (find_func_aliases): Handle pointer alignment via BIT_AND_EXPR.

2010-07-02  Richard Guenther  <rguenther@suse.de>

	* tree-ssa-structalias.c (find_func_aliases): Handle
	pointer alignment via BIT_AND_EXPR.
	* tree-vrp.c (extract_range_from_binary_expr): Likewise.

From-SVN: r161707

gcc/ChangeLog

 2010-07-02  Richard Guenther  <rguenther@suse.de>
 
+	* tree-ssa-structalias.c (find_func_aliases): Handle
+	pointer alignment via BIT_AND_EXPR.
+	* tree-vrp.c (extract_range_from_binary_expr): Likewise.
+
+2010-07-02  Richard Guenther  <rguenther@suse.de>
+
 	* tree-data-ref.c (initialize_data_dependence_relation): Handle
 	mismatching number of dimensions properly.
 

gcc/tree-ssa-structalias.c

@@ -4395,6 +4395,14 @@ find_func_aliases (gimple origt)
 	  if (gimple_assign_rhs_code (t) == POINTER_PLUS_EXPR)
 	    get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
 					   gimple_assign_rhs2 (t), &rhsc);
+	  else if (gimple_assign_rhs_code (t) == BIT_AND_EXPR
+		   && TREE_CODE (gimple_assign_rhs2 (t)) == INTEGER_CST)
+	    {
+	      /* Aligning a pointer via a BIT_AND_EXPR is offsetting
+		 the pointer.  Handle it by offsetting it by UNKNOWN.  */
+	      get_constraint_for_ptr_offset (gimple_assign_rhs1 (t),
+					     NULL_TREE, &rhsc);
+	    }
 	  else if ((CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (t))
 		    && !(POINTER_TYPE_P (gimple_expr_type (t))
 			 && !POINTER_TYPE_P (TREE_TYPE (rhsop))))

gcc/tree-vrp.c

@@ -2188,15 +2188,30 @@ extract_range_from_binary_expr (value_range_t *vr,
 
 	  return;
 	}
-      gcc_assert (code == POINTER_PLUS_EXPR);
-      /* For pointer types, we are really only interested in asserting
-	 whether the expression evaluates to non-NULL.  */
-      if (range_is_nonnull (&vr0) || range_is_nonnull (&vr1))
-	set_value_range_to_nonnull (vr, expr_type);
-      else if (range_is_null (&vr0) && range_is_null (&vr1))
-	set_value_range_to_null (vr, expr_type);
+      if (code == POINTER_PLUS_EXPR)
+	{
+	  /* For pointer types, we are really only interested in asserting
+	     whether the expression evaluates to non-NULL.  */
+	  if (range_is_nonnull (&vr0) || range_is_nonnull (&vr1))
+	    set_value_range_to_nonnull (vr, expr_type);
+	  else if (range_is_null (&vr0) && range_is_null (&vr1))
+	    set_value_range_to_null (vr, expr_type);
+	  else
+	    set_value_range_to_varying (vr);
+	}
+      else if (code == BIT_AND_EXPR)
+	{
+	  /* For pointer types, we are really only interested in asserting
+	     whether the expression evaluates to non-NULL.  */
+	  if (range_is_nonnull (&vr0) && range_is_nonnull (&vr1))
+	    set_value_range_to_nonnull (vr, expr_type);
+	  else if (range_is_null (&vr0) || range_is_null (&vr1))
+	    set_value_range_to_null (vr, expr_type);
+	  else
+	    set_value_range_to_varying (vr);
+	}
       else
-	set_value_range_to_varying (vr);
+	gcc_unreachable ();
 
       return;
     }